Category Archives: COX-2

Wogonin

Cancer:
Breast, lung (NSCLC), gallbladder carcinoma, osteosarcoma, colon, cervical

Action: Neuro-protective, anti-lymphangiogenesis, anti-angiogenic, anti-estrogenic, chemo-sensitizer, pro-oxidative, hypoxia-induced drug resistance, anti-metastatic, anti-tumor, anti-inflammatory

Wogonin is a plant monoflavonoid isolated from Scutellaria rivularis (Benth.) and Scutellaria baicalensis (Georgi).

Breast Cancer; ER+ & ER-

Effects of wogonin were examined in estrogen receptor (ER)-positive and -negative human breast cancer cells in culture for proliferation, cell-cycle progression, and apoptosis. Cell growth was attenuated by wogonin (50-200 microM), independently of its ER status, in a time- and concentration-dependent manner. Apoptosis was enhanced and accompanied by up-regulation of PARP and Caspase 3 cleavages as well as pro-apoptotic Bax protein. Akt activity was suppressed and reduced phosphorylation of its substrates, GSK-3beta and p27, was observed. Suppression of Cyclin D1 expression suggested the down-regulation of the Akt-mediated canonical Wnt signaling pathway.

ER expression was down-regulated in ER-positive cells, while c-ErbB2 expression and its activity were suppressed in ER-negative SK-BR-3 cells. Wogonin feeding to mice showed inhibition of tumor growth of T47D and MDA-MB-231 xenografts by up to 88% without any toxicity after 4 weeks of treatment. As wogonin was effective both in vitro and in vivo, our novel findings open the possibility of wogonin as an effective therapeutic and/or chemo-preventive agent against both ER-positive and -negative breast cancers, particularly against the more aggressive and hormonal therapy-resistant ER-negative types (Chung et al., 2008).

Neurotransmitter Action

Kim et al. (2011) found that baicalein and wogonin activated the TREK-2 current by increasing the opening frequency (channel activity: from 0.05 ± 0.01 to 0.17 ± 0.06 in baicalein treatment and from 0.03 ± 0.01 to 0.29 ± 0.09 in wogonin treatment), while leaving the single-channel conductance and mean open time unchanged. Baicalein continuously activated TREK-2, whereas wogonin transiently activated TREK-2. Application of baicalein and wogonin activated TREK-2 in both cell attached and excised patches, suggesting that baicalein and wogonin may modulate TREK-2 either directly or indirectly with different mechanisms. These results suggest that baicalein- and wogonin-induced TREK-2 activation help set the resting membrane potential of cells exposed to pathological conditions and thus may give beneficial effects in neuroprotection.

Anti-metastasic

The migration and invasion assay was used to evaluate the anti-metastasis effect of wogonin. Wogonin at the dose of 1–10 µM, which did not induce apoptosis, significantly inhibited the mobility and invasion activity of human gallbladder carcinoma GBC-SD cells. In addition, the expressions of matrix metalloproteinase (MMP)-2, MMP-9 and phosphorylated extracellular regulated protein kinase 1/2 (ERK1/2) but not phosphorylated Akt were dramatically suppressed by wogonin in a concentration-dependent manner. Furthermore, the metastasis suppressor maspin was confirmed as the downstream target of wogonin.

These findings suggest that wogonin inhibits cell mobility and invasion by up-regulating the metastasis suppressor maspin. Together, these data provide novel insights into the chemo-protective effect of wogonin, a main active ingredient of Chinese medicine Scutellaria baicalensis (Dong et al., 2011).

Anti-tumor and Anti-metastatic

Kimura & Sumiyoshi (2012) examined the effects of wogonin isolated from Scutellaria baicalensis roots on tumor growth and metastasis using a highly metastatic model in osteosarcoma LM8-bearing mice. Wogonin (25 and 50mg/kg, twice daily) reduced tumor growth and metastasis to the lung, liver and kidney, angiogenesis (CD31-positive cells), lymphangiogenesis (LYVE-1-positive cells), and TAM (F4/80-positive cell) numbers in the tumors of LM8-bearing mice. Wogonin (10–100µM) also inhibited increases in IL-1β production and cyclooxygenase (COX)-2 expression induced by lipopolysaccharide in THP-1 macrophages. The anti-tumor and anti-metastatic actions of wogonin may be associated with the inhibition of VEGF-C-induced lymphangiogenesis through a reduction in VEGF-C-induced VEGFR-3 phosphorylation by the inhibition of COX-2 expression and IL-1β production in Tumor-associated macrophages (TAMs).

Anti-inflammatory

Wogonin extracted from Scutellariae baicalensis and S. barbata is a cell-permeable and orally available flavonoid that displays anti-inflammatory properties. Wogonin is reported to suppress the release of NO by iNOS, PGE2 by COX-2, pro-inflammatory cytokines, and MCP-1 gene expression and NF-kB activation (Chen et al., 2008).

Hypoxia-Induced Drug Resistance (MDR)

Hypoxia-induced drug resistance is a major obstacle in the development of effective cancer therapy. The reversal abilities of wogonin on   hypoxia resistance were examined and the underlying mechanisms discovered. MTT assay revealed that hypoxia increased maximal 1.71-, 2.08-, and 2.15-fold of IC50 toward paclitaxel, ADM, and DDP in human colon cancer cell lines HCT116, respectively. Furthermore, wogonin showed strong reversal potency in HCT116 cells in hypoxia and the RF reached 2.05. Hypoxia-inducible factor-1α (HIF-1α) can activate the expression of target genes involved in glycolysis. Wogonin decreased the expression of glycolysis-related proteins (HKII, PDHK1, LDHA), glucose uptake, and lactate generation in a dose-dependent manner.

In summary, wogonin could be a good candidate for the development of a new multi-drug resistance (MDR) reversal agent and its reversal mechanism probably is due to the suppression of HIF-1α expression via inhibiting PI3K/Akt signaling pathway (Wang et al., 2013).

NSCLC

Wogonin, a flavonoid originated from Scutellaria baicalensis Georgi, has been shown to enhance TRAIL-induced apoptosis in malignant cells in in vitro studies. In this study, the effect of a combination of TRAIL and wogonin was tested in a non-small-cell lung cancer xenografted tumor model in nude mice. Consistent with the in vitro study showing that wogonin sensitized A549 cells to TRAIL-induced apoptosis, wogonin greatly enhanced TRAIL-induced suppression of tumor growth, accompanied with increased apoptosis in tumor tissues as determined by TUNEL assay.

The down-regulation of these antiapoptotic proteins was likely mediated by proteasomal degradation that involved intracellular reactive oxygen species (ROS), because wogonin robustly induced ROS accumulation and ROS scavengers butylated hydroxyanisole (BHA) and N-acetyl-L-cysteine (NAC) and the proteasome inhibitor MG132 restored the expression of these antiapoptotic proteins in cells co-treated with wogonin and TRAIL.

These results show for the first time that wogonin enhances TRAIL's anti-tumor activity in vivo, suggesting this strategy has an application potential for clinical anti-cancer therapy (Yang et al., 2013).

Colon Cancer

Following treatment with baicalein or wogonin, several apoptotic events were observed, including DNA fragmentation, chromatin condensation and increased cell-cycle arrest in the G1 phase. Baicalein and wogonin decreased Bcl-2 expression, whereas the expression of Bax was increased in a dose-dependent manner compared with the control. Furthermore, the induction of apoptosis was accompanied by an inactivation of phosphatidylinositol 3-kinase (PI3K)/Akt in a dose-dependent manner.

The administration of baicalein to mice resulted in the inhibition of the growth of HT-29 xenografts without any toxicity following 5 weeks of treatment. The results indicated that baicalein induced apoptosis via Akt activation in a p53-dependent manner in the HT-29 colon cancer cells and that it may serve as a chemo-preventive or therapeutic agent for HT-29 colon cancer (Kim et al., 2012).

Breast

The involvement of insulin-like growth factor-1 (IGF-1) and estrogen receptor α (ERα) in the inhibitory effect of wogonin on the breast adenocarcinoma growth was determined. Moreover, the effect of wogonin on the angiogenesis of chick chorioallantoic membrane (CAM) was also investigated. The results showed wogonin and ICI182780 both exhibited a potent ability to blunt IGF-1-stimulated MCF-7 cell growth. Either of wogonin and ICI182780 significantly inhibited ERα and p-Akt expressions in IGF-1-treated cells. The inhibitory effect of wogonin showed no difference from that of ICI182780 on IGF-1-stimulated expressions of ERα and p-Akt. Meanwhile, wogonin at different concentrations showed significant inhibitory effect on CAM angiogenesis.

These results suggest the inhibitory effect of wogonin on breast adenocarcinoma growth via inhibiting IGF-1-mediated PI3K-Akt pathway and regulating ERα expression. Furthermore, wogonin has a strong anti-angiogenic effect on CAM model (Ma et al., 2012).

Chemoresistance; Cervical Cancer, NSCLC

Chemoresistance to cisplatin is a major limitation of cisplatin-based chemotherapy in the clinic. The combination of cisplatin with other agents has been recognized as a promising strategy to overcome cisplatin resistance. Previous studies have shown that wogonin (5,7-dihydroxy-8-methoxyflavone), a flavonoid isolated from the root of the medicinal herb Scutellaria baicalensis Georgi, sensitizes cancer cells to chemotheraputics such as etoposide, adriamycin, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and TNF.

In this study, the non-small-cell lung cancer cell line A549 and the cervical cancer cell line HeLa were treated with wogonin or cisplatin individually or in combination. It was found for the first time that wogonin is able to sensitize cisplatin-induced apoptosis in both A549 cells and HeLa cells as indicated by the potentiation of activation of caspase-3, and cleavage of the caspase-3 substrate PARP in wogonin and cisplatin co-treated cells.

Results provided important new evidence supporting the potential use of wogonin as a cisplatin sensitizer for cancer therapy (He et al., 2012).

References

Chen LG, Hung LY, Tsai KW, et al. (2008). Wogonin, a bioactive flavonoid in herbal tea, inhibits inflammatory cyclooxygenase-2 gene expression in human lung epithelial cancer cells. Mol Nutr Food Res. 52:1349-1357.


Chung H, Jung YM, Shin DH, et al. (2008). Anti-cancer effects of wogonin in both estrogen receptor-positive and -negative human breast cancer cell lines in vitro and in nude mice xenografts. Int J Cancer, 122(4):816-22.


Dong P, Zhang Y, Gu J, et al. (2011). Wogonin, an active ingredient of Chinese herb medicine Scutellaria baicalensis, inhibits the mobility and invasion of human gallbladder carcinoma GBC-SD cells by inducing the expression of maspin. J Ethnopharmacol, 137(3):1373-80. doi: 10.1016/j.jep.2011.08.005.


He F, Wang Q, Zheng XL, et al. (2012). Wogonin potentiates cisplatin-induced cancer cell apoptosis through accumulation of intracellular reactive oxygen species. Oncology Reports, 28(2), 601-605. doi: 10.3892/or.2012.1841.


Kim EJ, Kang D, Han J. (2011). Baicalein and wogonin are activators of rat TREK-2 two-pore domain K+ channel. Acta Physiologica, 202(2):185–192. doi: 10.1111/j.1748-1716.2011.02263.x.


Kim SJ, Kim HJ, Kim HR, et al. (2012). Anti-tumor actions of baicalein and wogonin in HT-29 human colorectal cancer cells. Mol Med Rep, 6(6):1443-9. doi: 10.3892/mmr.2012.1085.


Kimura Y & Sumiyoshi M. (2012). Anti-tumor and anti-metastatic actions of wogonin isolated from Scutellaria baicalensis roots through anti-lymphangiogenesis. Phytomedicine, 20(3-4):328-336. doi:10.1016/j.phymed.2012.10.016


Ma X, Xie KP, Shang F, et al. (2012). Wogonin inhibits IGF-1-stimulated cell growth and estrogen receptor α expression in breast adenocarcinoma cell and angiogenesis of chick chorioallantoic membrane. Sheng Li Xue Bao, 64(2):207-12.


Wang H, Zhao L, Zhu LT, et al. (2013). Wogonin reverses hypoxia resistance of human colon cancer HCT116 cells via down-regulation of HIF-1α and glycolysis, by inhibiting PI3K/Akt signaling pathway. Mol Carcinog. doi: 10.1002/mc.22052.


Yang L, Wang Q, Li D, et al. (2013). Wogonin enhances anti-tumor activity of tumor necrosis factor-related apoptosis-inducing ligand in vivo through ROS-mediated down-regulation of cFLIPL and IAP proteins. Apoptosis, 18(5):618-26. doi: 10.1007/s10495-013-0808-8.

Ursolic acid

Cancer:
Glioblastoma, Lung, breast, colorectal, gastric, esophageal squamous carcinoma, prostate

Action:

Mitochondrial function, reactive oxygen species (ROS) generation.

Cytostatic, anti-inflammatory, chemo-prevention, COX-2 inhibitor, suppresses NF- κ B, induces IL-1 β , induces apoptosis

Ursolic acid, a pentacyclic triterpene acid found ubiquitously in the plant kingdom, including Rosmarinus officinalis (L.), Salvia officinalis (L.), Prunella vulgaris (L.), Psychotria serpens (L.) and Hyptis capitata (Jacq.). It has been shown to suppress the expression of several genes associated with tumorigenesis resulting in anti-inflammatory, anti-tumorigenic and chemo-sensitizing effects (Liu, 1995).

Glioblastoma Cancer

Ursolic acid, a natural pentacyclic triterpenic acid, possesses anticancer potential and diverse biological effects, but its correlation with glioblastoma multiforme cells and different modes of cell death is unclear. We studied the cellular actions of human GBM DBTRG-05MG cells after ursolic acid treatment and explored cell-selective killing effect of necrotic death as a cell fate.

Ursolic acid effectively reversed TMZ resistance and reduced DBTRG-05MG cell viability. Surprisingly, ursolic acid failed to stimulate the apoptotic and autophagic-related signaling networks. The necrotic death was characterized by annexin V/PI double-positive detection and release of HMGB1 and LDH. These ursolic acid-elicited responses were accompanied by ROS generation and glutathione depletion. Rapid mitochondrial dysfunction was paralleled by the preferential induction of necrosis, rather than apoptotic death. MPT is a phenomenon to provide the onset of mitochondrial depolarization during cellular necrosis. The opening of MPT pores that were mechanistically regulated by CypD, and ATP decline occurred in treated necrotic DBTRG-05MG cells. Cyclosporine A (an MPT pore inhibitor) prevented ursolic acid-provoked necrotic death and -involved key regulators.

The study by Lu et al., (2014) is the first to report that ursolic acid-modified mitochondrial function triggers defective death by necrosis in DBTRG-05MG cells rather than augmenting programmed death.

Gastric Cancer

Ursolic acid (UA) inhibits growth of BGC-803 cells in vitro in dose-dependent and time-dependent manner. Treated with UA in vivo, tumor cells can be arrested to G0/G1 stage. The apoptotic rate was significantly increased in tumor cells treated with UA both in vitro and in vivo. These results indicated that UA inhibits growth of tumor cells both in vitro and in vivo by decreasing proliferation of cells and inducing apoptosis (Wang et al., 2011).

Esophageal Squamous Carcinoma

The anti-neoplastic effects of combinations of anti-cancer drugs (5-fluorouracil, irinotecan and cisplatin) and triterpenes (ursolic acid, betulinic acid, oleanolic acid and a Japanese apricot extract (JAE) containing triterpenes) on esophageal squamous carcinoma cells were examined by the WST-8 (2-(2-methoxy- 4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium, monosodium salt) assay in vitro and by an animal model in vivo. Triterpenes and JAE showed additive and synergistic cytotoxic effects, respectively, on esophageal squamous carcinoma cells (YES-2 cells) by combinational use of 5-fluorouracil. JAE and 5-fluorouracil induced cell-cycle arrest at G2/M phase and at S phase, respectively, and caused apoptosis in YES-2 cells.

These results suggest that triterpenes, especially JAE, are effective supplements for enhancing the chemotherapeutic effect of 5-fluorouracil on esophageal cancer (Yamai et al., 2009).

COX-2 Inhibitor

Subbaramaiah et al. (2000) studied the effects of ursolic acid, a chemo-preventive agent, on the expression of cyclooxygenase-2 (COX-2). Treatment with ursolic acid suppressed phorbol 12-myristate 13-acetate (PMA)-mediated induction of COX-2 protein and synthesis of prostaglandin E2. Ursolic acid also suppressed the induction of COX-2 mRNA by PMA. Increased activator protein-1 activity and the binding of c-Jun to the cyclic AMP response element of the COX-2 promoter, effects were blocked by ursolic acid (Subbaramaiah et al., 2000).

Lung Cancer, Suppresses NF- κB

In terms of general anti-cancer mechanism, ursolic acid has also been found to suppress NF-κB activation induced by various carcinogens through the inhibition of the DNA binding of NF-κB. Ursolic acid also inhibits IκBα kinase and p65 phosphorylation (Shishodia et al., 2003). In particular, ursolic acid has been found to block cell-cycle progression and trigger apoptosis in lung cancer and may hence act as a chemoprevention agent for lung cancer (Hsu et al., 2004).

Breast Cancer

Ursolic acid is a potent inhibitor of MCF-7 cell proliferation. This triterpene exhibits both cytostatic and cytotoxic activity. It exerts an early cytostatic effect at G1 followed by cell death. Results suggest that alterations in cell-cycle phase redistribution of MCF-7 human breast cancer, by ursolic acid, may significantly influence MTT (colorimetric assays) reduction to formazan (Es-Saady et al., 1996).

Induces IL-1 β

Interleukin (IL)-1beta is a pro-inflammatory cytokine responsible for the onset of a broad range of diseases, such as inflammatory bowel disease and rheumatoid arthritis. It has recently been found that aggregated ursolic acid (UA), a triterpene carboxylic acid, is recognized by CD36 for generating reactive oxygen species (ROS) via NADPH oxidase (NOX) activation, thereby releasing IL-1beta protein from murine peritoneal macrophages (pMphi) in female ICR mice. In the present study, Ikeda et al. (2008) investigated the ability of UA to induce IL-1beta production in pMphi from 4 different strains of female mice as well as an established macrophage line. In addition, the different susceptibilities to UA-induced IL-1beta release were suggested to be correlated with the amount of superoxide anion (O2-) generated from the 5 different types of Mphi.

Notably, intracellular, but not extracellular, O2- generation was indicated to play a major role in UA-induced IL-1beta release. Together, these results indicate that the UA-induced IL-1beta release was strain-dependent, and the expression status of CD36 and gp91phox is strongly associated with inducibility.

Induces Apoptosis: Breast Cancer, Prostate Cancer

Ursolic acid (UA) induced apoptosis and modulated glucocorticoid receptor (GR) and Activator Protein-1 (AP-1) in MCF-7 breast cancer cells. UA is a GR modulator and may be considered as a potential anti-cancer agent in breast cancer (Kassi et al., 2009).

UA induces apoptosis via both extrinsic and intrinsic signaling pathways in cancer cells (Kwon et al., 2010). In PC-3 cells, UA inhibits proliferation by activating caspase-9 and JNK as well as FasL activation and Akt inhibition (Zhang et al., 2010). A significant proliferation inhibition and invasion suppression in both a dose- and time-dependent manner is observed in highly metastatic breast cancer MDA-MB-231 cells; this inhibition is related to the down-regulation of MMP2 and u-PA expression (Yeh et al., 2010).

Ursolic acid additionally stimulates the release of cytochrome C in HL-60 cells and breast cancer MCF-7 cells. The activation of caspase-3 in a cytochrome C-dependent manner induces apoptosis via the mitochondrial pathway (Qian et al., 2011).

Colorectal Cancer

Ursolic acid (UA) has strong anti-proliferative and apoptotic effects on human colon cancer HT-29 cells. UA dose-dependently decreased cell proliferation and induced apoptosis, accompanied by activation of caspase 3, 8 and 9. The effects may be mediated by alkaline sphingomyelinase activation (Andersson et al., 2003).

Ursolic acid (UA), using the colorectal cancer (CRC) mouse xenograft model and the HT-29 human colon carcinoma cell line, was evaluated for its efficacy against tumor growth in vivo and in vitro, and its molecular mechanisms were investigated. It was found that UA inhibits cancer growth without apparent toxicity. Furthermore, UA significantly suppresses the activation of several CRC-related signaling pathways and alters the expression of critical target genes. These molecular effects lead to the induction of apoptosis and inhibition of cellular proliferation.

These data demonstrate that UA possesses a broad range of anti-cancer activities due to its ability to affect multiple intracellular targets, suggesting that UA could be a novel multipotent therapeutic agent for cancer treatment (Lin et al., 2013).

Action: Anti-tumor, inhibits tumor cell migration and invasion

Ursolic acid (UA) is a sort of pentacyclic triterpenoid carboxylic acid purified from natural plant. UA has a series of biological effects such as sedative, anti-inflammatory, anti-bacterial, anti-diabetic, antiulcer, etc. It is discovered that UA has a broad-spectrum anti-tumor effect in recent years, which has attracted more and more scholars’ attention. This review explained anti-tumor actions of UA, including (1) the protection of cells’ DNA from different damages; (2) the anti-tumor cell proliferation by the inhibition of epidermal growth factor receptor mitogen-activated protein kinase signal or of FoxM1 transcription factors, respectively; (3) antiangiogenesis, (4) the immunological surveillance to tumors; (5) the inhibition of tumor cell migration and invasion; (6) the effect of UA on caspase, cytochromes C, nuclear factor kappa B, cyclooxygenase, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) or mammalian target of rapamycin signal to induce tumor cell apoptosis respectively, and etc. Moreover, UA has selective toxicity to tumor cells, basically no effect on normal cells.

Inhibition of Epidermal Growth Factor Receptor/ Mitogen-Activated Protein Kinase Pathway
Activation of mitogen-activated protein kinase (MAPK) allows cell excessive proliferation involved in the carcinogenic process (Park et al., 1999). Subfamilies of MAPK, metastasis.(24) Otherwise, UA suppresses the activation of NF-κB and down-regulation of the MMP-9 protein, which in turn contributes to its inhibitory effects on IL-1β or tumor necrosis factor α (TNF-α)-induced C6 glioma cell invasion (Huang et al., 2009).

U A suppresses inter cellular adhesion molecules-1 (ICAM-1) expression of non-small cell lung cancer (NSCLC) H3255, A549, Calu-6 cells, and significantly inhibits fibronectin expression in a concentration-dependent way. UA significantly suppresses the expression of MMP-9 and MMP-2 and inhibits protein kinase C activity in test cell lines, at the same time, UA reduces cell invasion in a concentration-dependent manner (Huang et al., 2011).

Cancer: Multiple myeloma

Action: Anti-inflammatory, down-regulates STAT3

When dealing with the multiple myeloma, by the way of activating the proto-oncogene-mediated c-Src, JAK1, JAK2, and ERKs, ursolic acid (UA) can not only inhibit the expression of IL-6-induced STAT3 but also downregulates the STAT3 by regulating gene products, such as cyclin D1, Bcl-2, Bcl-xL, surviving, Mcl-1 and VEGF. Above all, UA can inhibit the proliferation of multiple myeloma cells and induce apoptosis, to arrest cells at G1 phase and G0 phase of cell cycle (Pathak et al., 2007).

The essential oils of ginger (Zingiber officinale) and turmeric (Curcuma longa) contain a large variety of terpenoids, some of which possess anticancer, anti-ulcer, and antioxidant properties. Despite their importance, only four terpene synthases have been identified from the Zingiberaceae family: (+)-germacrene D synthase and (S)-β-bisabolene synthase from ginger rhizome, and α-humulene synthase and β-eudesmol synthase from shampoo ginger (Zingiber zerumbet) rhizome (Koo et al., 2012).

Cancer: Colorectal

Wong et al., have previously reported Signal Transducer and Activator of Transcription 3 (STAT3) to be constitutively activated in aldehyde dehydrogenase (ALDH)(+)/cluster of differentiation-133 (CD133)(+) colon cancer-initiating cells. In the present study they tested the efficacy of inhibiting STAT3 signaling in human colon cancer-initiating cells by ursolic acid (UA), which exists widely in fruits and herbs.

ALDH(+)/CD133(+) colon cancer-initiating cells. UA also reduced cell viability and inhibited tumor sphere formation of colon cancer-initiating cells, more potently than two other natural compounds, resveratrol and capsaicin. UA also inhibited the activation of STAT3 induced by interleukin-6 in DLD-1 colon cancer cells. Furthermore, daily administration of UA suppressed HCT116 tumor growth in mice in vivo.

Their results suggest STAT3 to be a target for colon cancer prevention. UA, a dietary agent, might offer an effective approach for colorectal carcinoma prevention by inhibiting persistently activated STAT3 in cancer stem cells.

References

 

Andersson D, Liu JJ, Nilsson A, Duan RD. (2003). Ursolic acid inhibits proliferation and stimulates apoptosis in HT29 cells following activation of alkaline sphingomyelinase. Anti-cancer Research, 23(4):3317-22.

 

Es-Saady D, Simon A, Jayat-Vignoles C, Chulia AJ, Delage C. (1996). MCF-7 cell-cycle arrested at G1 through ursolic acid, and increased reduction of tetrazolium salts. Anti-cancer Research, 16(1):481-6.

 

Hsu YL, Kuo PL, Lin CC. (2004). Proliferative inhibition, cell-cycle dysregulation, and induction of apoptosis by ursolic acid in human non-small-cell lung cancer A549 cells. Life Sciences, 75(19), 2303-2316.

 

Ikeda Y, Murakami A, Ohigashi H. (2008). Strain differences regarding susceptibility to ursolic acid-induced interleukin-1beta release in murine macrophages. Life Sci, 83(1-2):43-9. doi: 10.1016/j.lfs.2008.05.001.

 

Kassi E, Sourlingas TG, Spiliotaki M, et al. (2009). Ursolic Acid Triggers Apoptosis and Bcl-2 Down-regulation in MCF-7 Breast Cancer Cells. Cancer Investigation, 27(7):723-733. doi:10.1080/07357900802672712.

 

Kwon SH, Park HY, Kim JY, et al. (2010). Apoptotic action of ursolic acid isolated from Corni fructus in RC-58T/h/SA#4 primary human prostate cancer cells. Bioorg Med Chem Lett, 20:6435–6438. doi: 10.1016/j.bmcl.2010.09.073.

 

Lin J, Chen Y, Wei L, et al. (2013). Ursolic acid promotes colorectal cancer cell apoptosis and inhibits cell proliferation via modulation of multiple signaling pathways. Int J Oncol, (4):1235-43. doi: 10.3892/ijo.2013.2040.

 

Liu J. (1995). Pharmacology of oleanolic acid and ursolic acid. Journal of Ethnopharmacology, 49(2), 57-68.

 

Shishodia S, Majumdar S, Banerjee S, Aggarwal BB. (2003). Ursolic Acid Inhibits Nuclear Factor-OE ∫ B Activation Induced by Carcinogenic Agents through Suppression of IOE ∫ BOE± Kinase and p65 Phosphorylation. Cancer Research, 63(15), 4375-4383.

 

Subbaramaiah K, Michaluart P, Sporn MB, Dannenberg AJ. (2000). Ursolic Acid Inhibits Cyclooxygenase-2 Transcription in Human Mammary Epithelial Cells. Cancer Res, 60:2399

 

Qian J, Li X, Guo GY, et al. (2011). Potent anti-tumor activity of emodin on CNE cells in vitro through apoptosis. J Zhejiang Sci-Tech Univ (Chin), 42:756-759

 

Wang X, Zhang F, Yang L, et al. (2011). Ursolic Acid Inhibits Proliferation and Induces Apoptosis of Cancer Cells In Vitro and In Vivo. J Biomed Biotechnol, 2011:419343. doi: 10.1155/2011/419343.

 

Yamai H, et al. (2009). Triterpenes augment the inhibitory effects of anti-cancer drugs on growth of human esophageal carcinoma cells in vitro and suppress experimental metastasis in vivo. Int J Cancer, 125(4):952-60. doi: 10.1002/ijc.24433.

 

Yeh CT, Wu CH, Yen GC. (2010). Ursolic acid, a naturally occurring triterpenoid, suppresses migration and invasion of human breast cancer cells by modulating c-Jun N-terminal kinase, Akt and mammalian target of rapamycin signaling. Mol Nutr Food Res, 54:1285–1295. doi: 10.1002/mnfr.200900414.

 

Zhang Y, Kong C, Zeng Y, et al. (2010). Ursolic acid induces PC-3 cell apoptosis via activation of JNK and inhibition of Akt pathways in vitro. Mol Carcinog, 49:374–385.

 

Zhang LL, Wu BN, Lin Y et al. (2014) Research Progress of Ursolic Acid’s Anti-Tumor Actions. Chin J Integr Med 2014 Jan;20(1):72-79

 

Reference

 

Huang HC, Huang CY, Lin-Shiau SY, Lin JK. Ursolic acid inhibits IL-1beta or TNF-alpha-induced C6 glioma invasion through suppressing the association ZIP/p62 with PKC-zeta and downregulating the MMP-9 expression. Mol Carcinog 2009;48:517-531

 

Huang CY, Lin CY, Tsai CW, Yin MC. Inhibition of cell proliferation, invasion and migration by ursolic acid in human lung cancer cell lines. Toxicol In Vitro 2011;25:1274-1280.

 

Park KS, Kim NG, Kim JJ, Kim H, Ahn YH, Choi KY. Differential regulation of MAP kinase cascade in human colorectal tumorigenesis. Br J Cancer 1999;81:1116-1121.

 

 

Pathak AK, Bhutani M, Nair AS, Ahn KS, Chakraborty A, Kadara H, et al. Ursolic acid inhibits STAT3 activation pathway leading to suppression of proliferation and chemosensitization of human multiple myeloma cells. Mol Cancer Res 2007;5:943-595

 

 

Koo HJ, Gang DR. (2012) Suites of terpene synthases explain differential terpenoid production in ginger and turmeric tissues. PLoS One. 2012;7(12):e51481. doi: 10.1371/journal.pone.0051481.

 

 

Wang W, Zhao C, Jou D, Lü J, Zhang C, Lin L, Lin J. (2013) Ursolic acid inhibits the growth of colon cancer-initiating cells by targeting STAT3. Anticancer Res. 2013 Oct;33(10):4279-84.

 
Lu C-C, Huang B-R, Liao P-J, Yen G-C. Ursolic acid triggers a non-programmed death (necrosis) in human glioblastoma multiforme DBTRG-05MG cells through MPT pore opening and ATP decline. Molecular Nutrition & Food Research. 2014 DOI: 10.1002/mnfr.201400051

 

 

 

Theaflavin-2

Cancer: none noted

Action: Anti-inflammatory, induces apoptosis

Apoptosis

Theaflavin-2 (TF-2), a major component of black tea extract (Camellia sinensis [(L.) Kuntze]), induces apoptosis of human colon cancer cells and suppresses serum-induced cyclooxygenase-2 (COX-2) expression 1. The mechanisms of TF-2 for the activation of apoptosis were examined, and the impact on inflammatory genes in a broader panel of cells was evaluated and tested for whether topical anti-inflammatory effects could be observed in vivo. TF-2 triggered apoptosis in five other transformed cancer cell lines, inducing cell shrinkage, membrane blebbing, and mitochondrial clustering within 3 h of treatment. Topical application with TF-2 significantly reduced ear edema and produced a pattern of gene down-regulation similar to that observed in the cell model. These results suggest that the anti-inflammatory and pro-apoptotic activity of TF-2 may be exploited therapeutically in cancer and other diseases associated with inflammation (Gosslau et al., 2011).

Reference

Gosslau A, En Jao DL, Huang MT et al. (2011). Effects of the black tea polyphenol theaflavin-2 on apoptotic and inflammatory pathways in vitro and in vivo. Molecular Nutrition & Food Research, 55(2):198–208. doi: 10.1002/mnfr.201000165

Salvianolic acid-B / Salvinal

Cancer:
Head and neck squamous cell carcinoma, oral squamous cell carcinoma, glioma

Action: MDR, reduction of cardiotoxicity, COX-2 inhibitor, inflammatory-associated tumor development, anti-cancer

Salvia miltiorrhiza contains a variety of anti-tumor active ingredients, such as the water-soluble components, salvianolic acid A, salvianolic acid B, salvinal, and liposoluble constituents, tanshinone I, tanshinone IIA, dihydrotanshinone I, miltirone, cryptotanshinone, ailantholide, neo-tanshinlactone, and nitrogen-containing compounds. These anti-tumor active components play important roles in the different stages of tumor evolution, progression and metastasis (Zhang & Lu, 2010).

Anti-cancer/MDR

Aqueous extracts of Salvia miltiorrhizae Bunge have been extensively used in the treatment of cardiovascular disorders and cancer in Asia. Recently, a compound, 5-(3-hydroxypropyl)-7-methoxy-2-(3'-methoxy-4'-hydroxyphenyl)-3-benzo[b]furancarbaldehyde (salvinal), isolated from this plant showed inhibitory activity against tumor cell growth and induced apoptosis in human cancer cells. In the present study, we investigated the cytotoxic effect and mechanisms of action of salvinal in human cancer cell lines. Salvinal caused inhibition of cell growth (IC50 range, 4-17 microM) in a variety of human cancer cell lines.

In particular, salvinal exhibited similar inhibitory activity against parental KB, P-glycoprotein-overexpressing KB vin10 and KB taxol-50 cells, and multi-drug resistance-associated protein (MRP)-expressing etoposide-resistant KB 7D cells.

Taken together, our data demonstrate that salvinal inhibits tubulin polymerization, arrests cell-cycle at mitosis, and induces apoptosis. Notably, Salvinal is a poor substrate for transport by P-glycoprotein and MRP. Salvinal may be useful in the treatment of human cancers, particularly in patients with drug resistance (Chang et al., 2004).

Glioma

Salvianolic acid B (SalB) has been shown to exert anti-cancer effect in several cancer cell lines. SalB increased the phosphorylation of p38 MAPK and p53 in a dose-dependent manner. Moreover, blocking p38 activation by specific inhibitor SB203580 or p38 specific siRNA partly reversed the anti-proliferative and pro-apoptotic effects, and ROS production induced by SalB treatment.

These findings extended the anti-cancer effect of SalB in human glioma cell lines, and suggested that these inhibitory effects of SalB on U87 glioma cell growth might be associated with p38 activation mediated ROS generation. Thus, SalB might be concerned as an effective and safe natural anti-cancer agent for glioma prevention and treatment (Wang et al., 2013).

Reduced Cardiotoxicity

Clinical attempts to reduce the cardiotoxicity of arsenic trioxide (ATO) without compromising its anti-cancer activities remain an unresolved issue. In this study, Wang et al., (2013b) determined that Sal B can protect against ATO-induced cardiac toxicity in vivo and increase the toxicity of ATO toward cancer cells.

The combination treatment significantly enhanced the ATO-induced cytotoxicity and apoptosis of HepG2 cells and HeLa cells. Increases in apoptotic marker cleaved poly (ADP-ribose) polymerase and decreases in procaspase-3 expressions were observed through Western blot. Taken together, these observations indicate that the combination treatment of Sal B and ATO is potentially applicable for treating cancer with reduced cardiotoxic side effects.

Oral Cancer

Sal B has inhibitory effect on oral squamous cell carcinoma (OSCC) cell growth. The anti-tumor effect can be attributed to anti-angiogenic potential induced by a decreased expression of some key regulator genes of angiogenesis. Sal B may be a promising modality for treating oral squamous cell carcinoma.

Sal B induced growth inhibition in OSCC cell lines but had limited effects on premalignant cells. A total of 17 genes showed a greater than 3-fold change when comparing Sal B treated OSCC cells to the control. Among these genes, HIF-1α, TNFα and MMP9 are specifically inhibited; expression of THBS2 was up-regulated (Yang et al., 2011).

Head and Neck Cancer

Overexpression of cyclooxygenase-2 (COX-2) in oral mucosa has been associated with increased risk of head and neck squamous cell carcinoma (HNSCC). Celecoxib is a non-steroidal anti-inflammatory drug, which inhibits COX-2 but not COX-1. This selective COX-2 inhibitor holds promise as a cancer-preventive agent. Concerns about the cardiotoxicity of celecoxib limit its use in long-term chemo-prevention and therapy. Salvianolic acid B (Sal-B) is a leading bioactive component of Salvia miltiorrhiza Bge, which is used for treating neoplastic and chronic inflammatory diseases in China.

Tumor volumes in Sal-B treated group were significantly lower than those in celecoxib treated or untreated control groups (p < 0.05). Sal-B inhibited COX-2 expression in cultured HNSCC cells and in HNSCC cells isolated from tumor xenografts. Sal-B also caused dose-dependent inhibition of prostaglandin E(2) synthesis, either with or without lipopolysaccharide stimulation. Taking these results together, Sal-B shows promise as a COX-2 targeted anti-cancer agent for HNSCC prevention and treatment (Hao et al., 2009).

Inflammatory-associated tumor development

A half-dose of daily Sal-B (40 mg/kg/d) and celecoxib (2.5 mg/kg/d) significantly inhibited JHU-013 xenograft growth relative to mice treated with a full dose of Sal-B or celecoxib alone. The combination was associated with profound inhibition of COX-2 and enhanced induction of apoptosis. Taken together, these results strongly suggest that a combination of Sal-B, a multifunctional anti-cancer agent, with low-dose celecoxib holds potential as a new preventive strategy in targeting inflammatory-associated tumor development (Zhao et al., 2010).

Squamous Cell Carcinoma

The results showed that Sal B significantly decreased the squamous cell carcinoma (SCC) incidence from 64.7 (11/17) to 16.7% (3/18) (P=0.004); angiogenesis was inhibited in dysplasia and SCC (P<0.01), with a simultaneous decrease in the immunostaining of hypoxia-inducible factor 1alpha and vascular endothelium growth factor protein (P<0.05). The results suggested that Sal B had inhibitory effect against the malignant transformation of oral precancerous lesion and such inhibition may be related to the inhibition of angiogenesis (Zhou, Yang, & Ge, 2006).

References

Chang JY, Chang CY, Kuo CC, et al. (2004). Salvinal, a novel microtubule inhibitor isolated from Salvia miltiorrhizae Bunge (Danshen), with antimitotic activity in Multi-drug-sensitive and -resistant human tumor cells. Mol Pharmacol, 65(1):77-84.


Hao Y, Xie T, Korotcov A, et al. (2009). Salvianolic acid B inhibits growth of head and neck squamous cell carcinoma in vitro and in vivo via cyclooxygenase-2 and apoptotic pathways. Int J Cancer, 124(9):2200-9. doi: 10.1002/ijc.24160.


Wang ZS, Luo P, Dai SH, et al., (2013a). Salvianolic acid B induces apoptosis in human glioma U87 cells through p38-mediated ROS generation. Cell Mol Neurobiol, 33(7):921-8. doi: 10.1007/s10571-013-9958-z.


Wang M, Sun G, Wu P, et al. (2013b). Salvianolic Acid B prevents arsenic trioxide-induced cardiotoxicity in vivo and enhances its anti-cancer activity in vitro. Evid Based Complement Alternat Med, 2013:759483. doi: 10.1155/2013/759483.


Yang Y, Ge PJ, Jiang L, Li FL, Zhum QY. (2011). Modulation of growth and angiogenic potential of oral squamous carcinoma cells in vitro using salvianolic acid B. BMC Complement Altern Med, 11:54. doi: 10.1186/1472-6882-11-54.


Zhang W, Lu Y. (2010). Advances in studies on anti-tumor activities of compounds in Salvia miltiorrhiza. Zhongguo Zhong Yao Za Zhi, 35(3):389-92.


Zhao Y, Hao Y, Ji H, Fang Y, et al. (2010). Combination effects of salvianolic acid B with low-dose celecoxib on inhibition of head and neck squamous cell carcinoma growth in vitro and in vivo. Cancer Prev Res (Phila), 3(6):787-96. doi: 10.1158/1940-6207.CAPR-09-0243.


Zhou ZT, Yang Y, Ge JP. (2006). The preventive effect of salvianolic acid B on malignant transformation of DMBA-induced oral premalignant lesion in hamsters. Carcinogenesis, 27(4):826-32.

Piceatannol

Cancer: Esophageal, colorectal, breast

Action: Anti-inflammatory, anti-oxidative

Piceatannol, a naturally occurring analogue of resveratrol found in certain plants and berries of the Vaccinium genus, including Picea abies [(L.) H.Karst.], Aiphanes horrida [(Jacq.) Burret], Gnetum cleistostachyum (C. Y. Cheng), Vaccinium arboretum (Marshall), Vaccinium angustifolium (Aiton) and Vaccinium corymbosum (L.). It was previously identified as the active ingredient in herbal preparations in folk medicine. Piceatannol is an anti-inflammatory, immunomodulatory, and anti-proliferative stilbene that has been shown to interfere with the cytokine signaling pathway. It is isolated from various types of berries, grapes, rhubarb and sugar cane.

It has been shown that a diet containing freeze-dried black raspberries (BRB) inhibits the development of chemically-induced cancer in the rat esophagus. To provide insights into possible mechanisms by which BRB inhibit esophageal carcinogenesis, an ethanol (EtOH) extract of BRB was evaluated, and two component anthocyanins (cyanidin-3-O-glucoside and cyanidin-3-O−rutinoside) in BRB, for their effects on growth, apoptosis, and gene expression in rat esophageal epithelial cell lines. The EtOH extract and both anthocyanins selectively caused significant growth inhibition and induction of apoptosis in a highly tumorigenic cell line (RE-149 DHD) but not in a weakly tumorigenic line (RE-149).

The growth-inhibitory and pro-apoptotic effects were enhanced by the daily addition of the EtOH extract and the anthocyanins to the medium.

Esophageal Cancer

This differential effect may have been related to the relative amounts of anthocyanins in the extract vs.when they were added individually to the medium. It was hence concluded that the selective effects of the EtOH extract on the growth and apoptosis of highly tumorigenic rat esophageal epithelial cells in vitro may be due to preferential uptake and retention of its component anthocyanins, and this may also be responsible for the greater inhibitory effects of freeze-dried whole berries on tumor cells in vivo (Schwartz et al., 2009).

Colorectal

The effects of piceatannol on growth, proliferation, differentiation and cell-cycle distribution profile of the human colon carcinoma cell line Caco-2 were investigated. Growth of Caco-2 and HCT-116 cells was analyzed by crystal violet assay, which demonstrated dose- and time-dependent decreases in cell numbers. Treatment of Caco-2 cells with piceatannol reduced proliferation rate. No effect on differentiation was observed.

Determination of cell-cycle distribution by flow cytometry revealed an accumulation of cells in the S phase. Immunoblotting demonstrated that cyclin-dependent kinases (cdk) 2 and 6, as well as cdc2 were expressed at steady-state levels, whereas cyclin D1, cyclin B1 and cdk 4 were down-regulated. The abundance of p27Kip1 was also reduced, whereas the protein level of cyclin E was enhanced. Cyclin A levels were enhanced only at concentrations up to 100 µmol/L. These changes also were observed in studies with HCT-116 cells. On the basis of our findings, piceatannol can be considered to be a promising chemo-preventive or anti-cancer agent (Wolter et al., 2002).

Anti-inflammatory

Treatment of human myeloid cells with piceatannol suppressed TNF-induced DNA binding activity of NF-κB. In contrast, stilbene or rhaponticin (another analog of piceatannol) had no effect, suggesting the critical role of hydroxyl groups. The effect of piceatannol was not restricted to myeloid cells, as TNF-induced NF- κB activation was also suppressed in lymphocyte and epithelial cells. Piceatannol also inhibited NF-κB activated by H2O2, PMA, LPS, okadaic acid, and ceramide.

Piceatannol abrogated the expression of TNF-induced NF-κB-dependent reporter gene and of matrix metalloprotease-9, cyclooxygenase-2, and cyclin D1. When examined for the mechanism, it was found that piceatannol inhibited TNF-induced IκBα phosphorylation, p65 phosphorylation, p65 nuclear translocation, and IκBα kinase activation, but had no significant effect on IκBα degradation. Piceatannol inhibited NF-κB in cells with deleted Syk, indicating the lack of involvement of this kinase.

Overall, these results clearly demonstrate that hydroxyl groups of stilbenes are critical and that piceatannol, a tetrahydroxystilbene, suppresses NF- κB activation induced by various inflammatory agents through inhibition of IκBα kinase and p65 phosphorylation (Ashikawa et al., 2002).

There are multiple lines of evidence supporting that inflammation is causally linked to carcinogenesis. Abnormal up-regulation of cyclooxygenase-2 (COX-2), a rate-limiting enzyme in the prostaglandin biosynthesis, has been implicated in carcinogenesis. Trans-3,4,3',5'-tetrahydroxystilbene (piceatannol), a naturally occurring hydroxylated stilbene with potent anti-inflammatory and anti-oxidative activities, has been shown to inhibit the proliferation of several cancer cells by inducing apoptosis or blocking cell-cycle progression. The effect of piceatannol was examined on the activation of the nuclear transcription factor NF-κB, one of the major transcription factors that regulate pro-inflammatory COX- 2 gene transcription, in human mammary epithelial (MCF-10A) cells treated with the tumor promoter 12-O-tetradecanoylphorbol- 13-acetate (TPA).

When pre-treated to MCF-10A cells, piceatannol markedly inhibited TPA-induced NF-κB DNA binding to a greater extent than resveratrol and oxyresveratrol, stilbene analogs structurally related to piceatannol. Piceatannol also inhibited TPAinduced phosphorylation and degradation of IκBα as well as nuclear translocation of the phosphorylated form of p65, the functionally active subunit of NF-κB. Likewise, TPA-induced expression of COX-2 was abrogated by piceatannol pre-treatment. The thiol reducing agent dithiothreitol abolished the inhibitory effects of piceatannol on NF-κB DNA binding activity, suggesting that piceatannol may directly modify NF-kB (Liu et al., 2009).

Breast Cancer

Piceatannol (trans-3,4,3′,5′-tetrahydroxystilbene; PIC) exhibits immunosuppressive and anti-tumorigenic activities in several cell lines, and it was found that PIC inhibited migration and anchorage-independent growth of human mammary epithelial cells (MCF-10A) treated with the prototypic tumor promoter, 12-O-tetradecanoylphorbol-13-aceate (TPA). PIC treatment suppressed the TPA-induced activation of NF-κB and expression of cyclooxygenase-2 (COX-2) in MCF-10A cells. It was speculated that an electrophilic quinone formed as a consequence of oxidation of PIC bearing the catechol moiety may directly interact with critical cysteine thiols of IKKβ, thereby inhibiting its catalytic activity.

Results show that direct modification of IKKβ by PIC, presumably at the cysteine 179 residue, blocks NF-κB activation signaling and COX-2 induction in TPA-treated MCF-10A cells and also migration and transformation of these cells (Son et al., 2010).

References

Ashikawa K, Majumdar S, Banerjee S, et al. (2002). Piceatannol inhibits TNF-induced NF- κB activation and NF- κ B-mediated gene expression through suppression of IκBα kinase and p65 phosphorylation. The Journal of Immunology, 169(11):6490-7.


Liu D, Kim DH, Park JM. (2009). Piceatannol Inhibits Phorbol Ester-Induced NF- κ B Activation and COX-2 Expression in Cultured Human Mammary Epithelial Cells. Nutrition and Cancer, 61(6):855–63. doi: 10.1080/01635580903285080.


Schwartz SJ and Stoner GD. (2009). Black Raspberry Components Inhibit Proliferation, Induce Apoptosis, and Modulate Gene Expression in Rat Esophageal Epithelial Cells. Nutrition and Cancer, 61(6):816–26. doi: 10.1080/01635580903285148


Son PS, Park SA, Na HK, et al. (2010). Piceatannol, a catechol-type polyphenol, inhibits phorbol ester-induced NF- κ B activation and cyclooxygenase-2 expression in human breast epithelial cells: cysteine 179 of IKK β as a potential target. Carcinogenesis, 31(8):1442-1449. doi: 10.1093/carcin/bgq099.


Wolter F, Clausnitzer A, Akoglu B and Stein J. (2001). Down-regulation of the cyclin D1/Cdk4 complex occurs during resveratrol-induced cell-cycle arrest in colon cancer cell lines. J. Nutr, 132(2):298-302.

Paenol

Cancer: Gastric

Action: Attenuates nephrotoxicity, anti-inflammatory, anti-oxidant, inhibits TNF- α , induces apoptosis, COX-2 down-regulation

Inhibits TNF- α

Moutan Cortex, the root bark of Paeonia suffruticosa Andrews, has been used extensively as a traditional medicine for treatment of various diseases such as atherosclerosis, infection, and inflammation. Previous studies have revealed that the extracts of Moutan Cortex can inhibit nitric oxide and TNF- α in activated mouse peritoneal macrophages (Chung et al., 2007).

A variety of compounds including paeonoside, paeonolide, apiopaeonoside, paeoniflorin, oxypaeoniflorin, benzoyloxypaeoniflorin, benzoylpaeoniflorin, paeonol, and sugars have been identified in Moutan Cortex (Chen et al., 2006).

Attenuates Nephrotoxicity

Paeonol, a major compound of Moutan Cortex, has been found to attenuate cisplatin-induced nephrotoxicity in mice. Cisplatin is an effective chemotherapeutic agent that is used for the treatment of a variety of cancers; however, its nephrotoxicity limits the use of this drug.

Balb/c mice (6 to 8  w of age, weighing 20 to 25  g) were administered with Moutan Cortex (300  mg/kg) or paeonol (20 mg/kg) once a day. At day 4, mice received cisplatin (30, 20, or 10   mg/kg) intraperitoneally.

The paeonol-treated group showed marked attenuation of serum creatine and blood urea nitrogen levels as well as reduced levels of pro-inflammatory cytokines and nitric oxide when compared to the control group. In addition, the paeonol-treated group showed prolonged survival and marked attenuation of renal tissue injury. Taken together, these results demonstrated that paeonol can prevent the renal toxic effects of cisplatin (Lee et al., 2013).

Paeonol, a major phenolic component of Moutan Cortex, has various biological activities such as anti-aggregatory, anti-oxidant, anxiolytic-like, and anti-inflammatory functions (Ishiguro et al., 2006). In this study, paeonol treatment significantly reduced the elevated levels of serum creatinine and BUN. In addition, the role of pro-inflammatory cytokines in cisplatin-induced acute renal failure has been well documented (Faubel et al., 2007; Ramesh & Reeves, 2002), and elevation of the pro-inflammatory cytokines TNF-α and IL-1β as well as that of IL-6 has been demonstrated in humans with acute renal failure (Simmons et al., 2004).

Apoptosis-inducing & Gastric Cancer

Paeonol has significantly growth-inhibitory and apoptosis-inducing effects in gastric cancer cells both in vitro and in vivo. In vitro, paeonol caused dose-dependent inhibition on cell proliferation and induced apoptosis. Cell cycle analysis revealed a decreased proportion of cells in G0/G1 phase, with arrest at S. Paeonol treatment in gastric cancer cell line MFC and SGC-790 cells significantly reduced the expression of Bcl-2 and increased the expression of Bax in a concentration-related manner. Administration of paeonol to MFC tumor-bearing mice significantly lowered the tumor growth and caused tumor regression (Li et al., 2010).

COX-2 Down-regulation

One of the apoptotic mechanisms of paeonol is down-regulation of COX-2. p27 is up-regulated simultaneously and plays an important part in controlling cell proliferation and is a crucial factor in the Fas/FasL apoptosis pathway. Cell proliferation was inhibited by different concentrations of paeonol. By immunocytochemical staining, Ye et al. (2009) found that HT-29 cells treated with paeonol (0.024-1.504 mmol/L) reflected reduced expression of COX-2 and increased expression of p27 in a dose-dependent manner. RT-PCR showed that paeonol down-regulated COX-2 and up-regulated p27 in a dose- and time-dependent manner in HT-29 cells.

References

Chen G, Zhang L, Zhu Y. (2006). Determination of glycosides and sugars in moutan cortex by capillary electrophoresis with electrochemical detection. Journal of Pharmaceutical and Biomedical Analysis, 41(1):129–134.


Chung HS, M. Kang, C. Cho et al. (2007). Inhibition of nitric oxide and tumor necrosis factor-alpha by moutan cortex in activated mouse peritoneal macrophages. Biological and Pharmaceutical Bulletin, 30(5):912–916.


Faubel F, Lewis EC, Reznikov L et al. (2007). Cisplatin-induced acute renal failure is associated with an increase in the cytokines interleukin (IL)-1 β , IL-18, IL-6, and neutrophil infiltration in the kidney. Journal of Pharmacology and Experimental Therapeutics, 322(1):8–15.


Ishiguro K, Ando T, Maeda O et al. (2006). Paeonol attenuates TNBS-induced colitis by inhibiting NF- κ B and STAT1 transactivation. Toxicology and Applied Pharmacology, 217(1):35–42.


Lee HJ, Lee GY, Kim Hs, Bae Hs. (2013). Paeonol, a Major Compound of Moutan Cortex, Attenuates Cisplatin-Induced Nephrotoxicity in Mice. Evidence-Based Complementary and Alternative Medicine, 2013(2013), http://dx.doi.org/10.1155/2013/310989


Li N, Fan LL, Sun GP, et al. (2010). Paeonol inhibits tumor growth in gastric cancer in vitro and in vivo. World J Gastroenterol., 16(35):4483-90.


Ramesh G, Reeves wb. (2002). TNF- α mediates chemokine and cytokine expression and renal injury in cisplatin nephrotoxicity. Journal of Clinical Investigation, 110(6):835–842.


Simmons EM, Himmelfarb j, Sezer MT et al. (2004). Plasma cytokine levels predict mortality in patients with acute renal failure. Kidney International, 65(4):1357–1365.


Ye JM, Deng T, Zhang JB. (2009) Influence of paeonol on expression of COX-2 and p27 in HT-29 cells. World J Gastroenterol, 15(35):4410-4.

Oleanolic Acid (OA)

Cancer:
Pancreatic, hepatocellular carcinoma, prostate, lung, gastric, breast

Action: Radio-sensitizer, pro-apoptotic with 5-FU

Oleanolic acid (OA), a pentacyclic triterpenoid isolated from several plants, including Rosa woodsii (Lindl.), Prosopis glandulosa (Torr.), Phoradendron juniperinum (Engelm. ex A. Gray), Syzygium claviflorum (Roxburgh), Hyptis capitata (Jacq.) and Ternstromia gymnanthera (L.) exhibits potential anti-tumor activity against many tumor cell lines. Mistletoe contains water-insoluble triterpenoids, mainly oleanolic acid, that have anti-tumorigenic effects (StrŸh et al., 2013).

Pancreatic Cancer

Results of a study by Wei et al. (2012) showed that the proliferation of Panc-28 cells was inhibited by OA in a concentration-dependent manner, with an IC50 (The half maximal inhibitory concentration) value of 46.35 µg ml−1. The study also showed that OA could induce remarkable apoptosis and revealed that OA could induce Reactive Oxygen Species (ROS) generation, mitochondrial depolarization, release of cytochrome C, lysosomal membrane permeabilization and leakage of cathepin B. Further study confirmed that ROS scavenger vitamin C could reverse the apoptosis induced by OA in Panc-28 cells.

These results provide evidence that OA arrests the cell-cycle and induces apoptosis, possibly via ROS-mediated mitochondrial and a lysosomal pathway in Panc-28 cell.

The effects of the combination of OA and 5-fluorouracil (5-FU) on Panc-28 human pancreatic cells showed that combined use synergistically potentiated cell death effects on these cells, and that the pro-apoptotic effects were also increased. The expression of apoptosis related proteins was also affected in cells treated with the combination of OA and 5-FU, including activation of caspases-3 and the expression of Bcl-2/Bax, survivin and NF-κB (Wei et al., 2012).

Radio-sensitizer

The combined treatment of radiation with OA significantly decreased the clonogenic growth of tumor cells and enhanced the numbers of intracellular MN compared to irradiation alone. Furthermore, it was found that the synthesis of cellular GSH was inhibited concomitantly with the down-regulation of γ-GCS activity. Therefore, the utilization of OA as a radio-sensitizing agent for irradiation-inducing cell death offers a potential therapeutic approach to treat cancer (Wang et al., 2013).

Prostate Cancer, Lung Cancer, Gastric Cancer, Breast Cancer

Twelve derivatives of oleanolic acid (OA) have been synthesized and evaluated for their inhibitory activities against the growth of prostate PC3, breast MCF-7, lung A549, and gastric BGC-823 cancer cells by MTT assays. Within these series of derivatives, compound 17 exhibited the most potent cytotoxicity against PC3 cell line (IC50=0.39 µM) and compound 28 displayed the best activity against A549 cell line (IC50=0.22 µM). SAR analysis indicates that H-donor substitution at C-3 position of oleanolic acid may be advantageous for improvement of cytotoxicity against PC3, A549 and MCF-7 cell lines (Hao et al., 2013).

Hepatocellular Carcinoma

OA induced G2/M cell-cycle arrest through p21-mediated down-regulation of cyclin B1/cdc2. Cyclooxygenase-2 (COX-2) and p53 were involved in OA-exerted effect, and extracellular signal-regulated kinase-p53 signaling played a central role in OA-activated cascades responsible for apoptosis and cell-cycle arrest. OA demonstrated significant anti-tumor activities in hepatocellular carcinoma (HCC) in vivo and in vitro models. These data provide new insights into the mechanisms underlying the anti-tumor effect of OA (Wang et al., 2013).

References

Hao J, Liu J, Wen X, Sun H. (2013). Synthesis and cytotoxicity evaluation of oleanolic acid derivatives. Bioorg Med Chem Lett, 23(7):2074-7. doi: 10.1016/j.bmcl.2013.01.129.


StrŸh CM, JŠger S, Kersten A, et al. (2013). Triterpenoids amplify anti-tumoral effects of mistletoe extracts on murine B16.f10 melanoma in vivo. PLoS One, 8(4):e62168. doi: 10.1371/journal.pone.0062168.


Wang J, Yu M, Xiao L, et al. (2013). Radio-sensitizing effect of oleanolic acid on tumor cells through the inhibition of GSH synthesis in vitro. Oncol Rep, 30(2):917-24. doi: 10.3892/or.2013.2510.


Wang X, Bai H, Zhang X, et al. (2013). Inhibitory effect of oleanolic acid on hepatocellular carcinoma via ERK-p53-mediated cell-cycle arrest and mitochondrial-dependent apoptosis. Carcinogenesis, 34(6):1323-30. doi: 10.1093/carcin/bgt058.


Wei JT, Liu M, Liuz, et al. (2012). Oleanolic acid arrests cell-cycle and induces apoptosis via ROS-mediated mitochondrial depolarization and lysosomal membrane permeabilization in human pancreatic cancer cells. Journal of Applied Toxicology, 33(8):756–765. doi: 10.1002/jat.2725


Wei J, Liu H, Liu M, et al. (2012). Oleanolic acid potentiates the anti-tumor activity of 5-fluorouracil in pancreatic cancer cells. Oncol Rep, 28(4):1339-45. doi: 10.3892/or.2012.1921.

Moscatilin

Cancers:
Colon, lung, placenta, stomach, breast metastasis

Action: Anti-angiogenic, anti-metastatic, anti-tubulin, cytostatic, cytotoxic, cell-cycle arrest, anti-inflammatory

Stomach Cancer, Lung Cancer, Placental

The efficacy of using moscatilin, a natural anti-platelet agent extracted from the stems of Dendrobrium loddigesii, as an anti-cancer agent was studied. Results demonstrated that moscatilin exerts potent cytotoxic effect against cancer cell lines derived from different tissue origins, including those from the placenta, stomach, and lung, but not those from the liver. In addition, the mechanism of action of moscatilin may be related to its ability to induce a G2 phase arrest in responsive cells.

However, unlike some G2 arresting agents, moscatilin has no detectable inhibitory effect on cyclin B–cdc-2 kinase activity. Thus, the precise nature of its cytotoxic mechanism remains to be determined.

Results suggest that moscatilin is potentially efficacious for chemo-prevention and/or chemotherapy against some types of cancer (Ho & Chen, 2003).

Colorectal Cancer

The growth inhibition of moscatilin was screened on several human cancer cell lines. The effect of moscatilin on tubulin was detected in vitro. Following moscatilin treatment on colorectal HCT-116 cells, c-Jun NH(2)-terminal protein kinase (JNK) and caspase activation was studied by Western blot analysis, and DNA damage was done by Comet assay. Moscatilin induced a time-dependent arrest of the cell-cycle at G2/M, with an increase of cells at sub-G1. Moscatilin inhibited tubulin polymerization, suggesting that it might bind to tubulins. A parallel experiment showed that SP600125 significantly inhibits Taxol and vincristine induced HCT-116 cell apoptosis. This suggests that the JNK activation may be a common mechanism for tubulin-binding agents.

Collectively, results suggest that moscatilin induces apoptosis of colorectal HCT-116 cells via tubulin depolymerization and DNA damage leading to the activation of JNK and mitochondria-involved intrinsic apoptosis pathway (Chen et al., 2008).

Anti-inflammatory

Results showed that moscatilin (10-100 microM) had a significant inhibition in a concentration-dependent manner on pro-inflammatory enzymes (COX-2 and iNOS) expression and macrophage activation under LPS (100 ng/mL) treatment.

Hypoxia-inducible factor 1 (HIF-1) alpha was reported to initiate inflammation under cytokine stimulation or hypoxic conditions. Moscatilin had significant inhibition on HIF-1 expression via down-regulation of HIF-1 mRNA without affecting cell viability, translation machinery, or proteasome-mediated degradation of HIF-1. Collective data demonstrarted that moscatilin inhibited both COX-2 and iNOS expressions after LPS treatment in RAW264.7. Furthermore, moscatilin's inhibitory effect appears to be dependent on the repression of HIF-1alpha accumulation and NF-kappaB activation (Liu et al., 2010).

Lung Cancer; Angiogenesis

Moscatilin significantly inhibited growth of lung cancer cell line A549 (NSCLC) and suppressed growth factor-induced neovascularization. In addition, VEGF- and bFGF-induced cell proliferation, migration, and tube formation of HUVECs was markedly inhibited by moscatilin. Western blotting analysis of cell signaling molecules indicated that moscatilin inhibited ERK1/2, Akt, and eNOS signaling pathways in HUVECs.

Results suggest that inhibition of angiogenesis by moscatilin may be a major mechanism in cancer therapy (Tsai et al., 2010).

Lung Cancer

Investigation demonstrated that non-toxic concentrations of moscatilin were able to inhibit human non-small-cell lung cancer H23 cell migration and invasion. The inhibitory effect of moscatilin was associated with an attenuation of endogenous reactive oxygen species (ROS), in which hydroxyl radical was identified as a dominant species in the suppression of filopodia formation.

Results indicate a novel molecular basis of moscalitin inhibiting lung cancer cell motility and invasion. Moscalitin may have promising anti-metastatic potential as an agent for lung cancer therapy (Kowitdamrong, Chanvorachote, Sritularak & Pongrakhananon, 2013).

Breast Cancer; Metastasis

Moscatilin, derived from the orchid Dendrobrium loddigesii, has shown anti-cancer activity. The mechanism by which moscatilin suppresses the migration and metastasis of human breast cancer MDA-MB-231 cells in vitro and in vivo was evaluated.

Moscatilin was found to significantly inhibit breast cancer MDA-MB-231 cell migration by using scratch assays and Boyden chambers.

In an MDA-MB-231 metastatic animal model, moscatilin (100 mg/kg) significantly suppressed breast cancer metastasis to the lungs and reduced the number of metastatic lung nodules and lung weight without causing any toxicity.

Results indicated that moscatilin inhibited MDA-MB-231 cell migration via Akt- and Twist-dependent pathways, consistent with moscatilin's anti-metastatic activity in vivo. Therefore, moscatilin may be an effective compound for the prevention of human breast cancer metastasis (Pai et al., 2013).

References

Chen TH, Pan SL, Guh JH, et al. (2008). Moscatilin induces apoptosis in human colorectal cancer cells: a crucial role of c-Jun NH2-terminal protein kinase activation caused by tubulin depolymerization and DNA damage. Clinical Cancer Research, 14(13), 4250-4258. doi: 10.1158/1078-0432.CCR-07-4578.


Ho CK, Chen CC. (2003). Moscatilin from the orchid Dendrobrium loddigesii is a potential anti-cancer agent. Cancer Investigation, 21(5), 729-736.


Kowitdamrong A, Chanvorachote P, Sritularak B, Pongrakhananon V. (2013). Moscatilin inhibits lung cancer cell motility and invasion via suppression of endogenous reactive oxygen species. BioMed Research International., 2013, 765894. doi: 10.1155/2013/765894.


Liu YN, Pan SL, Peng CY, et al. (2010). Moscatilin repressed lipopolysaccharide-induced HIF-1alpha accumulation and NF-kappaB activation in murine RAW264.7 cells. Shock, 33(1), 70-5. doi: 10.1097/SHK.0b013e3181a7ff4a.


Pai HC, Chang LH, Peng CY, et al. (2013). Moscatilin inhibits migration and metastasis of human breast cancer MDA-MB-231 cells through inhibition of Akt and Twist signaling pathway.

Journal of Molecular Medicine (Berlin), 91(3), 347-56. doi: 10.1007/s00109-012-0945-5.

Tsai AC, Pan SL, Liao CH, et al. (2010). Moscatilin, a bibenzyl derivative from the India orchid Dendrobrium loddigesii, suppresses tumor angiogenesis and growth in vitro and in vivo. Cancer Letters, 292(2), 163-70. doi: 10.1016/j.canlet.2009.11.020.

Dietary Flavones

Cancer:
Prostate, colorectal., breast, pancreatic, bladder, ovarian, leukemia, liver, glioma, osteosarcoma, melanoma

Action: Anti-inflammatory, TAM resistance, cancer stem cells, down-regulate COX-2, apoptosis, cell-cycle arrest, anti-angiogenic, chemo-sensitzer, adramycin (ADM) resistance

Sulforaphane, Phenethyl isothiocyanate (PEITC), quercetin, epicatechin, catechin, Luteolin, apigenin

Anti-inflammatory

The anti-inflammatory activities of celery extracts, some rich in flavone aglycones and others rich in flavone glycosides, were tested on the inflammatory mediators tumor necrosis factor α (TNF-α) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in lipopolysaccharide-stimulated macrophages. Pure flavone aglycones and aglycone-rich extracts effectively reduced TNF-α production and inhibited the transcriptional activity of NF-κB, while glycoside-rich extracts showed no significant effects.

Celery diets with different glycoside or aglycone contents were formulated and absorption was evaluated in mice fed with 5% or 10% celery diets. Relative absorption in vivo was significantly higher in mice fed with aglycone-rich diets as determined by HPLC-MS/MS (where MS/MS is tandem mass spectrometry). These results demonstrate that deglycosylation increases absorption of dietary flavones in vivo and modulates inflammation by reducing TNF-α and NF-κB, suggesting the potential use of functional foods rich in flavones for the treatment and prevention of inflammatory diseases (Hostetler et al., 2012).

Colorectal Cancer

Association between the 6 main classes of flavonoids and the risk of colorectal cancer was examined using data from a national prospective case-control study in Scotland, including 1,456 incident cases and 1,456 population-based controls matched on age, sex, and residence area.

Dietary, including flavonoid, data were obtained from a validated, self-administered food frequency questionnaire. Risk of colorectal cancer was estimated using conditional logistic regression models in the whole sample and stratified by sex, smoking status, and cancer site and adjusted for established and putative risk factors.

The significant dose-dependent reductions in colorectal cancer risk that were associated with increased consumption of the flavonols quercetin, catechin, and epicatechin, remained robust after controlling for overall fruit and vegetable consumption or for other flavonoid intake. The risk reductions were greater among nonsmokers, but no interaction beyond a multiplicative effect was present.

This was the first of several a priori hypotheses to be tested in this large study and showed strong and linear inverse associations of flavonoids with colorectal cancer risk (Theodoratou et al., 2007).

Anti-angiogenic, Prostate Cancer

Luteolin is a common dietary flavonoid found in fruits and vegetables. The anti-angiogenic activity of luteolin was examined using in vitro, ex vivo, and in vivo models. Angiogenesis, the formation of new blood vessels from pre-existing vascular beds, is essential for tumor growth, invasion, and metastasis; hence, examination of this mechanism of tumor growth is essential to understanding new chemo-preventive targets. In vitro studies using rat aortic ring assay showed that luteolin at non-toxic concentrations significantly inhibited microvessel sprouting and proliferation, migration, invasion and tube formation of endothelial cells, which are key events in the process of angiogenesis. Luteolin also inhibited ex vivo angiogenesis as revealed by chicken egg chorioallantoic membrane assay (CAM) and matrigel plug assay.

Pro-inflammatory cytokines such as IL-1β, IL-6, IL-8, and TNF-α level were significantly reduced by the treatment of luteolin in PC-3 cells. Luteolin (10 mg/kg/d) significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model, indicating that luteolin inhibited tumorigenesis by targeting angiogenesis. Moreover, luteolin reduced cell viability and induced apoptosis in prostate cancer cells, which were correlated with the down-regulation of AKT, ERK, mTOR, P70S6K, MMP-2, and MMP-9 expressions.

Taken together, these findings demonstrate that luteolin inhibits human prostate tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis (Pratheeshkumar et al., 2012).

Pancreatic Cancer; Chemo-sensitizer

The potential of dietary flavonoids apigenin (Api) and luteolin (Lut) were assessed in their ability to enhance the anti-proliferative effects of chemotherapeutic drugs on BxPC-3 human pancreatic cancer cells; additionally, the molecular mechanism of the action was probed.

Simultaneous treatment with either flavonoid (0,13, 25 or 50µM) and chemotherapeutic drugs 5-fluorouracil (5-FU, 50µM) or gemcitabine (Gem, 10µM) for 60 hours resulted in less-than-additive effect (p<0.05). Pre-treatment for 24 hours with 13µM of either Api or Lut, followed by Gem for 36 hours was optimal to inhibit cell proliferation. Pre-treatment of cells with 11-19µM of either flavonoid for 24 hours resulted in 59-73% growth inhibition when followed by Gem (10µM, 36h). Lut (15µM, 24h) pre-treatment followed by Gem (10µM, 36h), significantly decreased protein expression of nuclear GSK-3β and NF-κB p65 and increased pro-apoptotic cytosolic cytochrome c. Pre-treatment of human pancreatic cancer cells BxPC-3 with low concentrations of Api or Lut hence effectively aid in the anti-proliferative activity of chemotherapeutic drugs (Johnson et al., 2013).

Breast Cancer; Chemo-sensitizer, Tamoxifen

The oncogenic molecules in human breast cancer cells are inhibited by luteolin treatment and it was found that the level of cyclin E2 (CCNE2) mRNA was higher in tumor cells than in normal paired tissue samples as assessed using real-time reverse-transcriptase polymerase chain reaction (RT-PCR) analysis (n=257).

Combined treatment with 4-OH-TAM and luteolin synergistically sensitized the TAM-R cells to 4-OH-TAM. These results suggest that luteolin can be used as a chemo-sensitizer to target the expression level of CCNE2 and that it could be a novel strategy to overcome TAM resistance in breast cancer patients (Tu et al., 2013).

Breast Cancer

Consumers of higher levels of Brassica vegetables, particularly those of the genus Brassica (broccoli, Brussels sprouts and cabbage), reduce their susceptibility to cancer at a variety of organ sites. Brassica vegetables contain high concentrations of glucosinolates that can be hydrolyzed by the plant enzyme, myrosinase, or intestinal microflora to isothiocyanates, potent inducers of cytoprotective enzymes and inhibitors of carcinogenesis. Oral administration of either the isothiocyanate, sulforaphane, or its glucosinolate precursor, glucoraphanin, inhibits mammary carcinogenesis in rats treated with 7,12-dimethylbenz[a]anthracene. To determine whether sulforaphane exerts a direct chemo-preventive action on animal and human mammary tissue, the pharmacokinetics and pharmacodynamics of a single 150 µmol oral dose of sulforaphane were evaluated in the rat mammary gland.

Sulforaphane metabolites were detected at concentrations known to alter gene expression in cell culture. Elevated cytoprotective NAD(P)H:quinone oxidoreductase (NQO1) and heme oxygenase-1 (HO-1) gene transcripts were measured using quantitative real-time polymerase chain reaction. An observed 3-fold increase in NQO1 enzymatic activity, as well as 4-fold elevated immunostaining of HO-1 in rat mammary epithelium, provide strong evidence of a pronounced pharmacodynamic action of sulforaphane. In a subsequent pilot study, eight healthy women undergoing reduction mammoplasty were given a single dose of a broccoli sprout preparation containing 200 µmol of sulforaphane. Following oral dosing, sulforaphane metabolites were readily measurable in human breast tissue enriched for epithelial cells. These findings provide a strong rationale for evaluating the protective effects of a broccoli sprout preparation in clinical trials of women at risk for breast cancer (Cornblatt et al., 2007).

In a proof of principle clinical study, the presence of disseminated tumor cells (DTCs) was demonstrated in human breast tissue after a single dose of a broccoli sprout preparation containing 200 µmol of sulforaphane. Together, these studies demonstrate that sulforaphane distributes to the breast epithelial cells in vivo and exerts a pharmacodynamic action in these target cells consistent with its mechanism of chemo-protective efficacy.

Such efficacy, coupled with earlier randomized clinical trials revealing the safety of repeated doses of broccoli sprout preparations , supports further evaluation of broccoli sprouts in the chemoprevention of breast and other cancers (Cornblatt et al., 2007).

CSCs

Recent research into the effects of sulforaphane on cancer stem cells (CSCs) has drawn a great deal of interest. CSCs are suggested to be responsible for initiating and maintaining cancer, and to contribute to recurrence and drug resistance. A number of studies have indicated that sulforaphane may target CSCs in different types of cancer through modulation of NF- κB, SHH, epithelial-mesenchymal transition and Wnt/β-catenin pathways. Combination therapy with sulforaphane and chemotherapy in preclinical settings has shown promising results (Li et al., 2013).

Anti-inflammatory

Sulforaphane has been found to down-regulate COX-2 expression in human bladder transitional cancer T24 cells at both transcriptional- and translational levels. Cyclooxygenase-2 (COX-2) overexpression has been associated with the grade, prognosis and recurrence of transitional cell carcinoma (TCC) of the bladder. Sulforaphane (5-20 microM) induced nuclear translocation of NF-kappaB and reduced its binding to the COX-2 promoter, a key mechanism for suppressing COX-2 expression by sulforaphane. Moreover, sulforaphane increased expression of p38 and phosphorylated-p38 protein. Taken together, these data suggest that p38 is essential in sulforaphane-mediated COX-2 suppression and provide new insights into the molecular mechanisms of sulforaphane in the chemoprevention of bladder cancer (Shan et al., 2009).

Bladder Cancer

An aqueous extract of broccoli sprouts potently inhibits the growth of human bladder carcinoma cells in culture and this inhibition is almost exclusively due to the isothiocyanates. Isothiocyanates are present in broccoli sprouts as their glucosinolate precursors and blocking their conversion to isothiocyanates abolishes the anti-proliferative activity of the extract.

Moreover, the potency of isothiocyanates in the extract in inhibiting cancer cell growth was almost identical to that of synthetic sulforaphane, as judged by their IC50 values (6.6 versus 6.8 micromol/L), suggesting that other isothiocyanates in the extract may be biologically similar to sulforaphane and that nonisothiocyanate substances in the extract may not interfere with the anti-proliferative activity of the isothiocyanates. These data show that broccoli sprout isothiocyanate extract is a highly promising substance for cancer prevention/treatment and that its anti-proliferative activity is exclusively derived from isothiocyanates (Tang et al., 2006).

Ovarian Cancer

Sulforaphane is an extract from the mustard family recognized for its anti-oxidation abilities, phase 2 enzyme induction, and anti-tumor activity. The cell-cycle arrest in G2/M by sulforaphane and the expression of cyclin B1, Cdc2, and the cyclin B1/CDC2 complex in PA-1 cells using Western blotting and co-IP Western blotting. The anti-cancer effects of dietary isothiocyanate sulforaphane on ovarian cancer were investigated using cancer cells line PA-1.

Sulforaphane -treated cells accumulated in metaphase by CDC2 down-regulation and dissociation of the cyclin B1/CDC2 complex.

These findings suggest that, in addition to the known effects on cancer prevention, sulforaphane may also provide anti-tumor activity in established ovarian cancer (Chang et al., 2013).

Leukemia Stem Cells

Isolated leukemia stem cells (LSCs) showed high expression of Oct4, CD133, β-catenin, and Sox2 and imatinib (IM) resistance. Differentially, CD34(+)/CD38(-) LSCs demonstrated higher BCR-ABL and β-catenin expression and IM resistance than CD34(+)/CD38(+) counterparts. IM and sulforaphane (SFN) combined treatment sensitized CD34(+)/CD38(-) LSCs and induced apoptosis, shown by increased caspase 3, PARP, and Bax while decreased Bcl-2 expression. Mechanistically, imatinib (IM) and sulforaphane (SFN) combined treatment resensitized LSCs by inducing intracellular reactive oxygen species (ROS). Importantly, β-catenin-silenced LSCs exhibited reduced glutathione S-transferase pi 1 (GSTP1) expression and intracellular GSH level, which led to increased sensitivity toward IM and sulforaphane.

It was hence demonstrated that IM and sulforaphane combined treatment effectively eliminated CD34(+)/CD38(-) LSCs. Since SFN has been shown to be well tolerated in both animals and human, this regimen could be considered for clinical trials (Lin et al., 2012).

DCIS Stem Cells

A miR-140/ALDH1/SOX9 axis has been found to be critical to basal cancer stem cell self-renewal and tumor formation in vivo, suggesting that the miR-140 pathway may be a promising target for preventive strategies in patients with basal-like Ductal Carcinoma in Situ (DCIS). The dietary compound sulforaphane has been found to decrease Transcription factor SOX-9 and Acetaldehyde dehydrogenases (ALDH1), and thereby reduced tumor growth in vivo (Li et al., 2013).

Glioma, Prostate Cancer, Colon Cancer, Breast Cancer, Liver Cancer

Phenethyl isothiocyanate (PEITC), a natural dietary isothiocyanate, inhibits angiogenesis. The effects of PEITC were examined under hypoxic conditions on the intracellular level of the hypoxia inducible factor (HIF-1α) and extracellular level of the vascular endothelial growth factor (VEGF) in a variety of human cancer cell lines. Gupta et al., (2013) observed that PEITC suppressed the HIF-1α accumulation during hypoxia in human glioma U87, human prostate cancer DU145, colon cancer HCT116, liver cancer HepG2, and breast cancer SkBr3 cells. PEITC treatment also significantly reduced the hypoxia-induced secretion of VEGF.

Suppression of HIF-1α accumulation during treatment with PEITC in hypoxia was related to PI3K and MAPK pathways.

Taken together, these results suggest that PEITC inhibits the HIF-1α expression through inhibiting the PI3K and MAPK signaling pathway and provide a new insight into a potential mechanism of the anti-cancer properties of PEITC.

Breast Cancer Metastasis

Breast tumor metastasis is a leading cause of cancer-related deaths worldwide. Breast tumor cells frequently metastasize to brain and initiate severe therapeutic complications. The chances of brain metastasis are further elevated in patients with HER2 overexpression. The MDA-MB-231-BR (BR-brain seeking) breast tumor cells stably transfected with luciferase were injected into the left ventricle of mouse heart and the migration of cells to brain was monitored using a non-invasive IVIS bio-luminescent imaging system.

Results demonstrate that the growth of metastatic brain tumors in PEITC treated mice was about 50% less than that of control. According to Kaplan Meir's curve, median survival of tumor-bearing mice treated with PEITC was prolonged by 20.5%. Furthermore, as compared to controls, we observed reduced HER2, EGFR and VEGF expression in the brain sections of PEITC treated mice. These results demonstrate the anti-metastatic effects of PEITC in vivo in a novel breast tumor metastasis model and provides the rationale for further clinical investigation (Gupta et al., 2013).

Osteosarcoma, Melanoma

Phenethyl isothiocyanate (PEITC) has been found to induce apoptosis in human osteosarcoma U-2 OS cells. The following end points were determined in regard to human malignant melanoma cancer A375.S2 cells: cell morphological changes, cell-cycle arrest, DNA damage and fragmentation assays and morphological assessment of nuclear change, reactive oxygen species (ROS) and Ca2+ generations, mitochondrial membrane potential disruption, and nitric oxide and 10-N-nonyl acridine orange productions, expression and activation of caspase-3 and -9, B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax), Bcl-2, poly (adenosine diphosphate-ribose) polymerase, and cytochrome c release, apoptosis-inducing factor and endonuclease G. PEITC

It was therefore concluded that PEITC-triggered apoptotic death in A375.S2 cells occurs through ROS-mediated mitochondria-dependent pathways (Huang et al., 2013).

Prostate Cancer

The glucosinolate-derived phenethyl isothiocyanate (PEITC) has recently been demonstrated to reduce the risk of prostate cancer (PCa) and inhibit PCa cell growth. It has been shown that p300/CBP-associated factor (PCAF), a co-regulator for the androgen receptor (AR), is upregulated in PCa cells through suppression of the mir-17 gene. Using AR-responsive LNCaP cells, the inhibitory effects of PEITC were observed on the dihydrotestosterone-stimulated AR transcriptional activity and cell growth of PCa cells.

Expression of PCAF was upregulated in PCa cells through suppression of miR-17. PEITC treatment significantly decreased PCAF expression and promoted transcription of miR-17 in LNCaP cells. Functional inhibition of miR-17 attenuated the suppression of PCAF in cells treated by PEITC. Results indicate that PEITC inhibits AR-regulated transcriptional activity and cell growth of PCa cells through miR-17-mediated suppression of PCAF, suggesting a new mechanism by which PEITC modulates PCa cell growth (Yu et al., 2013).

Bladder Cancer; Adramycin (ADM) Resistance

The role of PEITC on ADM resistance reversal of human bladder carcinoma T24/ADM cells has been examined, including an increased drug sensitivity to ADM, cell apoptosis rates, intracellular accumulation of Rhodamine-123 (Rh-123), an increased expression of DNA topoisomerase II (Topo-II), and a decreased expression of multi-drug resistance gene (MDR1), multi-drug resistance-associated protein (MRP1), bcl-2 and glutathione s transferase π (GST-π). The results indicated that PEITC might be used as a potential therapeutic strategy to ADM resistance through blocking Akt and activating MAPK pathway in human bladder carcinoma (Tang et al., 2013).

Breast Cancer; Chemo-enhancing

The synergistic effect between paclitaxel (taxol) and phenethyl isothiocyanate (PEITC) on the inhibition of breast cancer cells has been examined. Two drug-resistant breast cancer cell lines, MCF7 and MDA-MB-231, were treated with PEITC and taxol. Cell growth, cell-cycle, and apoptosis were examined.

The combination of PEITC and taxol significantly decreased the IC50 of PEITC and taxol over each agent alone. The combination also increased apoptosis by more than 2-fold over each single agent in both cell lines. A significant increase of cells in the G2/M phases was detected. Taken together, these results indicated that the combination of PEITC and taxol exhibits a synergistic effect on growth inhibition in breast cancer cells. This combination deserves further study in vivo (Liu et al., 2013).

References

Chang CC, Hung CM, Yang YR, Lee MJ, Hsu YC. (2013). Sulforaphane induced cell-cycle arrest in the G2/M phase via the blockade of cyclin B1/CDC2 in human ovarian cancer cells. J Ovarian Res, 6(1):41. doi: 10.1186/1757-2215-6-41


Cornblatt BS, Ye LX, Dinkova-Kostova AT, et al. (2007). Preclinical and clinical evaluation of sulforaphane for chemoprevention in the breast. Carcinogenesis, 28(7):1485-1490. doi: 10.1093/carcin/bgm049


Gupta B, Chiang L, Chae K, Lee DH. (2013). Phenethyl isothiocyanate inhibits hypoxia-induced accumulation of HIF-1 α and VEGF expression in human glioma cells. Food Chem, 141(3):1841-6. doi: 10.1016/j.foodchem.2013.05.006.


Gupta P, Adkins C, Lockman P, Srivastava SK. (2013). Metastasis of Breast Tumor Cells to Brain Is Suppressed by Phenethyl Isothiocyanate in a Novel In Vivo Metastasis Model. PLoS One, 8(6):e67278. doi:10.1371/journal.pone.0067278


Hostetler G, Riedl K, Cardenas H, et al. (2012). Flavone deglycosylation increases their anti-inflammatory activity and absorption. Molecular Nutrition & Food Research, 56(4):558-569. doi: 10.1002/mnfr.201100596


Huang SH, Hsu MH, Hsu SC, et al. (2013). Phenethyl isothiocyanate triggers apoptosis in human malignant melanoma A375.S2 cells through reactive oxygen species and the mitochondria-dependent pathways. Hum Exp Toxicol. doi: 10.1177/0960327113491508


Johnson JL, Gonzalez de Mejia E. (2013). Interactions between dietary flavonoids apigenin or luteolin and chemotherapeutic drugs to potentiate anti-proliferative effect on human pancreatic cancer cells, in vitro. Food Chem Toxicol, 60:83-91. doi: 10.1016/j.fct.2013.07.036.


Li Q, Yao Y, Eades G, Liu Z, Zhang Y, Zhou Q. (2013). Down-regulation of miR-140 promotes cancer stem cell formation in basal-like early stage breast cancer. Oncogene. doi: 10.1038/onc.2013.226.


Li Y, Zhang T. (2013). Targeting cancer stem cells with sulforaphane, a dietary component from broccoli and broccoli sprouts. Future Oncol, 9(8):1097-103. doi: 10.2217/fon.13.108.


Lin LC, Yeh CT, Kuo CC, et al. (2012). Sulforaphane potentiates the efficacy of imatinib against chronic leukemia cancer stem cells through enhanced abrogation of Wnt/ β-catenin function. J Agric Food Chem, 60(28):7031-9. doi: 10.1021/jf301981n.


Liu K, Cang S, Ma Y, Chiao JW. (2013). Synergistic effect of paclitaxel and epigenetic agent phenethyl isothiocyanate on growth inhibition, cell-cycle arrest and apoptosis in breast cancer cells. Cancer Cell Int, 13(1):10. doi: 10.1186/1475-2867-13-10.


Pratheeshkumar P, Son YO, Budhraja A, et al. (2012). Luteolin inhibits human prostate tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis. PLoS One, 7(12):52279. doi: 10.1371/journal.pone.0052279.


Tang K, Lin Y, Li LM. (2013). The role of phenethyl isothiocyanate on bladder cancer ADM resistance reversal and its molecular mechanism. Anat Rec (Hoboken), 296(6):899-906. doi: 10.1002/ar.22677.


Tang L, Zhang Y, Jobson HE, et al. (2006). Potent activation of mitochondria-mediated apoptosis and arrest in S and M phases of cancer cells by a broccoli sprout extract. Mol Cancer Ther, 5(4):935-44. doi: 10.1158/1535-7163.MCT-05-0476


Theodoratou E, Kyle J, Cetnarskyj R, et al. (2007). Dietary flavonoids and the risk of colorectal cancer. Cancer Epidemiol Biomarkers Prev,16(4):684-93.


Tu SH, Ho CT, Liu MF, et al. (2013). Luteolin sensitizes drug-resistant human breast cancer cells to tamoxifen via the inhibition of cyclin E2 expression. Food Chem, 141(2):1553-61. doi: 10.1016/j.foodchem.2013.04.077.


Shan Y, Wu K, Wang W, et al. (2009). Sulforaphane down-regulates COX-2 expression by activating p38 and inhibiting NF-kappaB-DNA-binding activity in human bladder T24 cells. Int J Oncol, 34(4):1129-34.


Yu C, Gong AY, Chen D, et al. (2013). Phenethyl isothiocyanate inhibits androgen receptor-regulated transcriptional activity in prostate cancer cells through suppressing PCAF. Mol Nutr Food Res. doi: 10.1002/mnfr.201200810.

Cryptotanshinone (See also Tanshinone)

Cancer:
Prostate, breast, cervical., leukemia, hepatocellular carcinoma

Action: Anti-inflammatory, cell-cycle arrest, inhibits dihydrotestosterone (DHT), anti-proliferative, hepato-protective

Cryptotanshinone is a major constituent of tanshinones from Salvia miltiorrhiza (Bunge).

Tanshinone IIA and cryptotanshinone could induce CYP3A activity (Qiu et al., 2103).

Anti-proliferative Agent

Cryptotanshinone (CPT), a natural compound, is a potential anti-cancer agent. Chen et al., (2010) have shown that CPT inhibited cancer cell proliferation by arresting cells in G(1)-G(0) phase of the cell-cycle. This is associated with the inhibition of cyclin D1 expression and retinoblastoma (Rb) protein phosphorylation.

Furthermore, they found that CPT inhibited the signaling pathway of the mammalian target of rapamycin (mTOR), a central regulator of cell proliferation. This is evidenced by the findings that CPT inhibited type I insulin-like growth factor I- or 10% fetal bovine serum-stimulated phosphorylation of mTOR, p70 S6 kinase 1, and eukaryotic initiation factor 4E binding protein 1 in a concentration- and time-dependent manner. Expression of constitutively active mTOR conferred resistance to CPT inhibition of cyclin D1 expression and Rb phosphorylation, as well as cell growth. The results suggest that CPT is a novel anti-proliferative agent.

Anti-inflammatory; COX-2, PGE2

Cyclooxygenase-2 (COX-2) is a key enzyme that catalyzes the biosynthesis of prostaglandins from arachidonic acid and plays a critical role in some pathologies including inflammation, neurodegenerative diseases and cancer. Cryptotanshinone is a major constituent of tanshinones and has well-documented anti-oxidative and anti-inflammatory effects.

This study confirmed the remarkable anti-inflammatory effect of cryptotanshinone in the carrageenan-induced rat paw edema model. Since the action of cryptotanshinone on COX-2 has not been previously described, in this study, Jin et al. (2006) examined the effect of cryptotanshinone on cyclooxygenase activity in the exogenous arachidonic acid-stimulated insect sf-9 cells, which highly express human COX-2 or human COX-1, and on cyclooxygenases expression in human U937 promonocytes stimulated by lipopolysaccharide (LPS) plus phorbolmyristate acetate (PMA).

Cryptotanshinone reduced prostaglandin E2 synthesis and reactive oxygen species generation catalyzed by COX-2, without influencing COX-1 activity in cloned sf-9 cells. In PMA plus LPS-stimulated U937 cells, cryptotanshinone had negligible effects on the expression of COX-1 and COX-2, at either a mRNA or protein level. These results demonstrate that the anti-inflammatory effect of cryptotanshinone is directed against enzymatic activity of COX-2, not against the transcription or translation of the enzyme.

Prostate Cancer

Cryptotanshinone was identified as a potent STAT3 inhibitor. Cryptotanshinone rapidly inhibited STAT3 Tyr705 phosphorylation in DU145 prostate cancer cells and the growth of the cells through 96 hours of the treatment. Inhibition of STAT3 Tyr705 phosphorylation in DU145 cells decreased the expression of STAT3 downstream target proteins such as cyclin D1, survivin, and Bcl-xL.

Cryptotanshinone can suppress Bcl-2 expression and augment Fas sensitivity in DU145 prostate cancer cells. Park et al. (2010) show that JNK and p38 MAPK act upstream of Bcl-2 expression in Fas-treated DU145 cells, and that cryptotanshinone significantly blocked activation of these kinases. Moreover, cryptotanshinone sensitized several tumor cells to a broad range of anti-cancer agents. Collectively, the data suggest that cryptotanshinone has therapeutic potential in the treatment of human prostate cancer (Park et al., 2010).

Cryptotanshinone was colocalized with STAT3 molecules in the cytoplasm and inhibited the formation of STAT3 dimers. Computational modeling showed that cryptotanshinone could bind to the SH2 domain of STAT3. These results suggest that cryptotanshinone is a potent anti-cancer agent targeting the activation STAT3 protein. It is the first report that cryptotanshinone has anti-tumor activity through the inhibition of STAT3 (Shin et al., 2009).

Prostate Cancer; Androgen Receptor Positive

Anti-androgens to reduce or prevent androgens binding to androgen receptor (AR) are widely used to suppress AR-mediated PCa growth; however, the androgen depletion therapy is only effective for a short period of time. Xu et al., (2012) found that cryptotanshinone (CTS), with a structure similar to dihydrotestosterone (DHT), can effectively inhibit the DHT-induced AR transactivation and prostate cancer cell growth. Their results indicated that 0.5 µM CTS effectively suppresses the growth of AR-positive PCa cells, but has little effect on AR negative PC-3 cells and non-malignant prostate epithelial cells.

Furthermore, data indicated that CTS could modulate AR transactivation and suppress the DHT-mediated AR target genes expression in both androgen responsive PCa LNCaP cells and castration resistant CWR22rv1 cells. The mechanistic studies indicate that CTS functions as an AR inhibitor to suppress androgen/AR-mediated cell growth and PSA expression by blocking AR dimerization and the AR-coregulator complex formation.

Furthermore, they showed that CTS effectively inhibits CWR22Rv1 cell growth and expressions of AR target genes in the xenograft animal model. The previously un-described mechanisms of CTS may explain how CTS inhibits the growth of PCa cells and help us to establish new therapeutic concepts for the treatment of PCa.

Breast Cancer, Cervical Cancer, Leukemia, Hepatocellular Carcinoma

The three tanshinone derivatives, tanshinone I, tanshinone IIA, and cryptotanshinone, exhibited significant in vitro cytotoxicity against several human carcinoma cell lines (Wang et al., 2007).

Tanshinone I was found to inhibit the growth and invasion of breast cancer cells both in vitro and in vivo through regulation of adhesion molecules including ICAM-1 and VCAM-1 (Nizamutdinova et al., 2008), and induce apoptosis of leukemia cells by interfering with the mitochondrial transmembrane potential (ΔΨm), increasing the expression of Bax, as well as activating caspase-3 (Liu et al., 2010). Tanshinone IIA has been reported to inhibit the growth of cervical cancer cells through disrupting the assembly of microtubules, and induces G2/M phase arrest and apoptosis (Pan et al., 2010).

This compound can also inhibit invasion and metastasis of hepatocellular carcinoma (HCC) cells both in vitro and in vivo, by suppressing the expression of the metalloproteinases, MMP2 and MMP9 and interfering with the NFκB signaling pathway (Xu et al., 2009).

Breast Cancer

Cryptotanshione was reported to induce cell-cycle arrest at the G1-G0 phase, which was accompanied by the inhibition of cyclin D1 expression, retinoblastoma (Rb) protein phosphorylation, and of the rapamycin (mTOR) signaling pathway (Chen et al., 2010).

Hepato-protective Effect

Cryptotanshinone (20 or 40mg/kg) was orally administered 12 and 1h prior to GalN (700mg/kg)/LPS (10µg/kg) injection. The increased mortality and TNF- α levels by GalN/LPS were declined by cryptotanshinone pre-treatment. In addition, cryptotanshinone attenuated GalN/LPS-induced apoptosis, characterized by the blockade of caspase-3, -8, and -9 activation, as well as the release of cytochrome c from the mitochondria. Furthermore, cryptotanshinone significantly inhibited the activation of NF-κB and suppressed the production of pro-inflammatory cytokines.

These findings suggest that the hepato-protective effect of cryptotanshinone is likely to be associated with its anti-apoptotic activity and the down-regulation of MAPKs and NF-κB associated at least in part with suppressing TAK1 phosphorylation (Jin et al., 2013).

References

Chen W, Luo Y, Liu L, Zhou H, Xu B, Han X, Shen T, Liu Z, Lu Y, Huang S. (2010). Cryptotanshinone Inhibits Cancer Cell Proliferation by Suppressing Mammalian Target of Rapamycin–Mediated Cyclin D1 Expression and Rb Phosphorylation. Cancer Prev Res (Phila), 3(8):1015-25. doi: 10.1158/1940-6207.CAPR-10-0020. Epub 2010 Jul 13.

Jin DZ, Yina LL, Jia XQ, Zhu XZ. (2006). Cryptotanshinone inhibits cyclooxygenase-2 enzyme activity but not its expression. European Journal of Pharmacology, 549(1-3):166-72. doi:10.1016/j.ejphar.2006.07.055

Jin VQ, Jiang S, Wu YL, et al. (2013). Hepato-protective effect of cryptotanshinone from Salvia miltiorrhiza in d-galactosamine/lipopolysaccharide-induced fulminant hepatic failure. Phytomedicine. doi:10.1016/j.phymed.2013.07.016

Liu JJ, Liu WD, Yang HZ, et al. (2010). Inactivation of PI3k/Akt signaling pathway and activation of caspase-3 are involved in tanshinone I-induced apoptosis in myeloid leukemia cells in vitro. Ann Hematol, 89:1089–1097. doi: 10.1007/s00277-010-0996-z.

Nizamutdinova IT, Lee GW, Lee JS, et al. (2008). Tanshinone I suppresses growth and invasion of human breast cancer cells, MDA-MB-231, through regulation of adhesion molecules. Carcinogenesis, 29(10):1885-1892. doi:10.1093/carcin/bgn151

Pan TL, Hung YC, Wang PW, et al. (2010). Functional proteomic and structural insights into molecular targets related to the growth-inhibitory effect of tanshinone IIA on HeLa cells. Proteomics,10:914–929.

Park IJ, Kim MJ, Park OJ, et al. (2010). Cryptotanshinone sensitizes DU145 prostate cancer cells to Fas(APO1/CD95)-mediated apoptosis through Bcl-2 and MAPK regulation. Cancer Lett, 298:88–98. doi: 10.1016/j.canlet.2010.06.006.

Qiu F, Jiang J, Ma Ym, et al. (2013). Opposite Effects of Single-Dose and Multidose Administration of the Ethanol Extract of Danshen on CYP3A in Healthy Volunteers. Evidence-Based Complementary and Alternative Medicine, 2013(2013) http://dx.doi.org/10.1155/2013/730734

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Berberine

Cancer:
Liver,leukemia, breast, prostate, epidermoid (squamous-cell carcinoma), cervical.,testicular, melanoma, lymphoma, hepatoma

Action: Radio-sensitizer, anti-inflammatory, cell-cycle arrest, angiogenesis, chemo-enhancing, anti-metastatic, anti-oxidative

Berberine is a major phytochemical component of the roots and bark of herbal plants such as Berberis, Hydrastis canadensis and Coptis chinensis. It has been implicated in the cytotoxic effects on multiple cancer cell lines.

Anti-inflammatory

Berberine is an isoquinoline alkaloid widely distributed in natural herbs, including Rhizoma Coptidis chinensis and Epimedium sagittatum (Sieb. et Zucc.), a widely prescribed Chinese herb (Chen et al., 2008). It has a broad range of bioactivities, such as anti-inflammatory, anti-bacterial., anti-diabetes, anti-ulcer, sedation, protection of myocardial ischemia-reperfusion injury, expansion of blood vessels, inhibition of platelet aggregation, hepato-protective, and neuroprotective effects (Lau et al., 2001; Yu et al., 2005; Kulkarni & Dhir, 2010; Han et al., 2011; Ji, 2011). Berberine has been used in the treatment of diarrhea, neurasthenia, arrhythmia, diabetes, and so forth (Ji, 2011).

Angiogenesis, Chemo-enhancing

Inhibition of tumor invasion and metastasis is an important aspect of berberine's anti-cancer activities (Tang et al., 2009; Ho et al., 2009). A few studies have reported berberine's inhibition of tumor angiogenesis (Jie et al., 2011; Hamsa & Kuttan, 2012). In addition, its combination with chemotherapeutic drugs or irradiation could enhance the therapeutic effects (Youn et al., 2008; Hur et al., 2009).

Cell-cycle Arrest

The potential molecular targets and mechanisms of berberine are rather complicated. Berberine interacts with DNA or RNA to form a berberine-DNA or a berberine-RNA complex, respectively (Islam & Kumar. 2009; Li et al., 2012). Berberine is also identified as an inhibitor of several enzymes, such as N-acetyltransferase (NAT), cyclooxygenase-2 (COX-2), and telomerase (Sun et al., 2009).

Other mechanisms of berberine are mainly related to its effect on cell-cycle arrest and apoptosis, including regulation of cyclin-dependent kinase (CDK) family of proteins (Sun et al., 2009; Mantena, Sharma, & Katiyar, 2006) and expression regulation of B-cell lymphoma 2 (Bcl-2) family of proteins (such as Bax, Bcl-2, and Bcl-xL) (Sun et al., 2009), and caspases (Eom et al., 2010; Mantena, Sharma, & Katiyar, 2006). Furthermore, berberine inhibits the activation of the nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and induces the formation of intracellular reactive oxygen species (ROS) in cancer cells (Sun et al., 2009; Eom et al., 2010). Interestingly, these effects might be specific for cancer cells (Sun et al., 2009).

Several studies have shown that berberine has anti-cancer potential by interfering with the multiple aspects of tumorigenesis and tumor progression in both in vitro and in vivo experiments. These observations have been well summarized in recent reports (Sun et al., 2009; Tan et al., 2011). Berberine inhibits the proliferation of multiple cancer cell lines by inducing cell-cycle arrest at the G1 or G 2 / M phases and by apoptosis (Sun et al., 2009; Eom et al., 2010; Burgeiro et al., 2011). In addition, berberine induces endoplasmic reticulum stress (Chang et al., 1990; Eom et al., 2010) and autophagy (Wang et al., 2010) in cancer cells.

However, compared with clinically prescribed anti-cancer drugs, the cytotoxic potency of berberine is much lower, with an IC50 generally at 10 µM to 100 µM depending on the cell type and treatment duration in vitro (Sun et al., 2009). Besides, berberine also induces morphologic differentiation in human teratocarcinoma (testes) cells (Chang et al., 1990).

Anti-metastatic

The effect of berberine on invasion, migration, metastasis, and angiogenesis is mediated through the inhibition of focal adhesion kinase (FAK), NF-κB, urokinase-type plasminogen-activator (u-PA), matrix metalloproteinase 2 (MMP-2), and matrix metalloproteinase 9 (MMP-9) (Ho et al., 2009; Hamsa & Kuttan. (2011); reduction of Rho kinase-mediated Ezrin phosphorylation (Tang et al., 2009); reduction of the expression of COX-2, prostaglandin E, and prostaglandin E receptors (Singh et al., 2011); down-regulation of hypoxia-inducible factor 1 (HIF-1), vascular endothelial growth factor (VEGF), pro-inflammatory mediators (Jie et al., 2011; Hamsa & Kuttan, 2012).

Hepatoma, Leukaemia

The cytotoxic effects of Coptis chinensis extracts and their major constituents on hepatoma and leukaemia cells in vitro have been investigated. Four human liver cancer cell lines, namely HepG2, Hep3B, SK-Hep1 and PLC/PRF/5, and four leukaemia cell lines, namely K562, U937, P3H1 and Raji, were investigated. C. chinensis exhibited strong activity against SK-Hep1 (IC50 = 7 microg/mL) and Raji (IC50 = 4 microg/mL) cell lines. Interestingly, the two major compounds of C. chinensis, berberine and coptisine, showed a strong inhibition on the proliferation of both hepatoma and leukaemia cell lines. These results suggest that the C. chinensis extract and its major constituents berberine and coptisine possess active anti-hepatoma and anti-leukaemia activities (Lin, 2004).

Leukemia

The steady-state level of nucleophosmin/B23 mRNA decreased during berberine-induced (25 g/ml, 24 to 96 hours) apoptosis of human leukemia HL-60 cells. A decline in telomerase activity was also observed in HL-60 cells treated with berberine. A stable clone of nucleophosmin/B23 over-expressed in HL-60 cells was selected and found to be less responsive to berberine-induced apoptosis. About 35% to 63% of control vector–transfected cells (pCR3) exhibited morphological characteristics of apoptosis, while about 8% to 45% of nucleophosmin/B23-over-expressed cells (pCR3-B23) became apoptotic after incubation with 15 g/ml berberine for 48 to 96 hours.

These results indicate that berberine-induced apoptosis is associated with the down-regulation of nucleophosmin/B23 and telomerase activity. Nucleophosmin/B23 may play an important role in the control of the cellular response to apoptosis induction (Hsing, 1999).

Prostate Cancer

In vitro treatment of androgen-insensitive (DU145 and PC-3) and androgen-sensitive (LNCaP) prostate cancer cells with berberine inhibited cell proliferation and induced cell death in a dose-dependent (10-100 micromol/L) and time-dependent (24–72 hours) manner. Berberine significantly (P < 0.05-0.001) enhanced apoptosis of DU145 and LNCaP cells with induction of a higher ratio of Bax/Bcl-2 proteins, disruption of mitochondrial membrane potential., and activation of caspase-9, caspase-3, and poly(ADP-ribose) polymerase.

The effectiveness of berberine in checking the growth of androgen-insensitive, as well as androgen-sensitive, prostate cancer cells without affecting the growth of normal prostate epithelial cells indicates that it may be a promising candidate for prostate cancer therapy (Mantena, 2006).

In another study, the treatment of human prostate cancer cells (PC-3) with berberine-induced dose-dependent apoptosis; however, this effect of berberine was not seen in non-neoplastic human prostate epithelial cells (PWR-1E). Berberine-induced apoptosis was associated with the disruption of the mitochondrial membrane potential., release of apoptogenic molecules (cytochrome c and Smac/DIABLO) from mitochondria and cleavage of caspase-9,-3 and PARP proteins.

Berberine-induced apoptosis was blocked in the presence of the anti-oxidant, N-acetylcysteine, through the prevention of disruption of mitochondrial membrane potential and subsequently release of cytochrome c and Smac/DIABLO. Taken together, these results suggest that the berberine-mediated cell death of human prostate cancer cells is regulated by reactive oxygen species, and therefore suggests that berberine may be considered for further studies as a promising therapeutic candidate for prostate cancer (Meeran, 2008).

Breast Cancer

DNA microarray technology has been used to understand the molecular mechanism underlying the anti-cancer effect of berberine carcinogenesis in two human breast cancer cell lines, the ER-positive MCF-7 and ER-negative MDA-MB-231 cells; specifically, whether it affects the expression of cancer-related genes. Treatment of the cancer cells with berberine markedly inhibited their proliferation in a dose- and time-dependent manner. The growth-inhibitory effect was much more profound in MCF-7 cell line than that in MDA-MB-231 cells.

IFN-β is among the most important anti-cancer cytokines, and the up-regulation of this gene by berberine is, at least in part, responsible for its anti-proliferative effect. The results of this study implicate berberine as a promising extract for chemoprevention and chemotherapy of certain cancers (Kang, 2005).

Breast Cancer Metastasis

Berberine also inhibits the growth of Anoikis-resistant MCF-7 and MDA-MB-231 breast cancer cell lines by inducing cell-cycle arrest. Anoikis, or detachment-induced apoptosis, may prevent cancer progression and metastasis by blocking signals necessary for survival of localized cancer cells. Resistance to anoikis is regarded as a prerequisite for metastasis; however, little is known about the role of berberine in anoikis-resistance.

The anoikis-resistant cells have a reduced growth rate and are more invasive than their respective adherent cell lines. The effect of berberine on growth was compared to that of doxorubicine, which is a drug commonly used to treat breast cancer, in both the adherent and anoikis-resistant cell lines. Berberine promoted the growth inhibition of anoikis-resistant cells to a greater extent than doxorubicine treatment. Treatment with berberine-induced cell-cycle arrest at G0/G1 in the anoikis-resistant MCF-7 and MDA-MB-231 cells was compared to untreated control cells. These results reveal that berberine can efficiently inhibit growth by inducing cell-cycle arrest in anoikis-resistant MCF-7 and MDA-MB-231 cells. Further analysis of these phenotypes is essential for understanding the effect of berberine on anoikis-resistant breast cancer cells, which would be relevant for the therapeutic targeting of breast cancer metastasis (Kim, 2010).

Melanoma

Berberine inhibits melanoma cancer cell migration by reducing the expressions of cyclooxygenase-2, prostaglandin E2 and prostaglandin E2 receptors. The effects and associated molecular mechanism of berberine on human melanoma cancer cell migration using melanoma cell lines A375 and Hs294 were probed in an in vitro cell migration assay, indicating that over- expression of cyclo-oxygenase (COX)-2, its metabolite prostaglandin E2 (PGE2) and PGE2 receptors promote the migration of cells.

Moreover, berberine inhibited the activation of nuclear factor-kappa B (NF-kB), an up- stream regulator of COX-2, in A375 cells, and treatment of cells with caffeic acid phenethyl ester, an inhibitor of NF-kB, inhibited cell migration. Together, these results indicate that berberine inhibits melanoma cell migration, an essential step in invasion and metastasis, by inhibition of COX-2, PGE2 and PGE2 receptors (Sing, 2011).

Cell-cycle Arrest, Squamous-cell Carcinoma

The in vitro treatment of human epidermoid carcinoma A431 cells with berberine decreases cell viability and induces cell death in a dose (5-75 microM)- and time (12–72 hours)-dependent manner, which was associated with an increase in G(1) arrest. G(0)/G(1) phase of the cell-cycle is known to be controlled by cyclin dependent kinases (Cdk), cyclin kinase inhibitors (Cdki) and cyclins.

Pre-treatment of A431 cells with the pan-caspase inhibitor (z-VAD-fmk) significantly blocked the berberine-induced apoptosis in A431 cells confirmed that berberine-induced apoptosis is mediated through activation of caspase 3-dependent pathway.

Together, these results indicate berberine as a chemotherapeutic agent against human epidermoid carcinoma A431 (squamous-cell) cells in vitro; further in vivo studies are required to determine whether berberine could be an effective chemotherapeutic agent for the management of non-melanoma skin cancers (Mantena, 2006).

Cervical Cancer, Radio-sensitizer

Cervical cancer remains one of the major killers amongst women worldwide. In India, a cisplatin based chemo/radiotherapy regimen is used for the treatment of advanced cervical cancer. Evidence shows that most of the chemotherapeutic drugs used in current clinical practice are radio-sensitizers. Natural products open a new avenue for treatment of cancer, as they are generally tolerated at high doses. Animal studies have confirmed the anti-tumorigenic activity of natural products, such as curcumin and berberine.

Berberine is a natural chemo-preventive agent, extracted from Berberis aristata, which has been shown to suppress and retard carcinogenesis by inhibiting inflammation.

The combined therapy of cisplatin/berberine and radiotherapy produced up-regulation of pro-apoptotic proteins Bax and p73, while causing down regulation of the anti-apoptotic proteins Bcl-xL, COX-2, cyclin D1. This additionally was accompanied by increased activity of caspase-9 and caspase-3, and reduction in telomerase activity. Results demonstrated that the treatment combination of berberine/cisplatin had increased induction of apoptosis relative to cisplatin alone (Komal., Singh, & Deshwal., 2013).

Anti-oxidative; Breast, Liver and Colon Cancer

The effect of B. vulgaris extract and berberine chloride on cellular thiobarbituric acid reactive species (TBARS) formation (lipid peroxidation), diphenyle–alpha-picrylhydrazyl (DPPH) oxidation, cellular nitric oxide (NO) radical scavenging capability, superoxide dismutase (SOD), glutathione peroxidase (GPx), acetylcholinesterase (AChE) and alpha-gulcosidase activities were spectrophotometrically determined.

Barberry crude extract contains 0.6 mg berberine/mg crude extract. Barberry extract showed potent anti-oxidative capacity through decreasing TBARS, NO and the oxidation of DPPH that is associated with GPx and SOD hyperactivation. Both berberine chloride and barberry ethanolic extract were shown to have inhibitory effect on the growth of breast, liver and colon cancer cell lines (MCF7, HepG2 and CACO-2, respectively) at different incubation times starting from 24 hours up to 72 hours and the inhibitory effect increased with time in a dose-dependent manner.

This work demonstrates the potential of the barberry crude extract and its active alkaloid, berberine, for suppressing lipid peroxidation, suggesting a promising use in the treatment of hepatic oxidative stress, Alzheimer and idiopathic male factor infertility. As well, berberis vulgaris ethanolic extract is a safe non-toxic extract as it does not inhibit the growth of PBMC that can induce cancer cell death (Abeer et al., 2013).

Source:

Alkaloids Isolated from Natural Herbs as the Anti-cancer Agents. Evidence-Based Complementary and Alternative Medicine. Volume 2012 (2012) http://dx.doi.org/10.1155/2012/485042

References

Burgeiro A, Gajate C, Dakir EH, et al. (2011). Involvement of mitochondrial and B-RAF/ERK signaling pathways in berberine-induced apoptosis in human melanoma cells. Anti-Cancer Drugs, 22(6):507–518.


Chang KSS, Gao C, Wang LC. (1990). Berberine-induced morphologic differentiation and down-regulation of c-Ki-ras2 protooncogene expression in human teratocarcinoma cells. Cancer Letters, 55(2):103–108.


Chen J, ZHao H, Wang X, et al. (2008). Analysis of major alkaloids in Rhizoma coptidis by capillary electrophoresis-electrospray-time of flight mass spectrometry with different background electrolytes. Electrophoresis, 29(10):2135–2147.


Eom KS, Kim HJ, So HS, et al. (2010). Berberine-induced apoptosis in human glioblastoma T98G Cells Is mediated by endoplasmic reticulum stress accompanying reactive oxygen species and mitochondrial dysfunction. Biological and Pharmaceutical Bulletin, 33(10):1644–1649.


El-Wahab AEA, Ghareeb DA, et al. (2013). In vitro biological assessment of berberis vulgaris and its active constituent, berberine: anti-oxidants, anti-acetylcholinesterase, anti-diabetic and anti-cancer effects. BMC Complementary and Alternative Medicine, 13:218 doi:10.1186/1472-6882-13-218


Hamsa TP & Kuttan G. (2011). Berberine inhibits pulmonary metastasis through down-regulation of MMP in metastatic B16F-10 melanoma cells. Phytotherapy Research, 26(4):568–578.


Hamsa TP & Kuttan G. (2012). Anti-angiogenic activity of berberine is mediated through the down-regulation of hypoxia-inducible factor-1, VEGF, and pro-inflammatory mediators. Drug and Chemical Toxicology, 35(1):57–70.


Han J, Lin H, Huang W. (2011). Modulating gut microbiota as an anti-diabetic mechanism of berberine. Medical Science Monitor, 17(7):RA164–RA167.


Ho YT, Yang JS, Li TC, et al. (2009). Berberine suppresses in vitro migration and invasion of human SCC-4 tongue squamous cancer cells through the inhibitions of FAK, IKK, NF-κB, u-PA and MMP-2 and -9. Cancer Letters, 279(2):155–162.


Hur JM, Hyun MS, Lim SY, Lee WY, Kim D. (2009). The combination of berberine and irradiation enhances anti-cancer effects via activation of p38 MAPK pathway and ROS generation in human hepatoma cells. Journal of Cellular Biochemistry, 107(5):955–964.


Islam MM & Kumar GS. (2009). RNA-binding potential of protoberberine alkaloids: spectroscopic and calorimetric studies on the binding of berberine, palmatine, and coralyne to protonated RNA structures. DNA and Cell Biology, 28(12):637–650.


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Jie S, Li H, Tian Y, et al. (2011). Berberine inhibits angiogenic potential of Hep G2 cell line through VEGF down-regulation in vitro. Journal of Gastroenterology and Hepatology, 26(1):179–185.


Kang JX, Liu J, Wang J, He C, Li FP. (2005). The extract of huanglian, a medicinal herb, induces cell growth arrest and apoptosis by up-regulation of interferon-β and TNF-α in human breast cancer cells. Carcinogenesis, 26(11):1934-1939. doi:10.1093/carcin/bgi154


Kim JB, Yu JH, Ko E, et al. (2010). The alkaloid Berberine inhibits the growth of Anoikis-resistant MCF-7 and MDA-MB-231 breast cancer cell lines by inducing cell-cycle arrest. Phytomedicine, 17(6):436-40. doi: 10.1016/j.phymed.2009.08.012.


Komal Singh M, & Deshwal VK. (2013). Natural plant product berberine/cisplatin based radiotherapy for cervical cancer: The new and effective method to treat cervical cancer. Global Journal of Research on Medicinal Plants and Indigenous Medicine, 2(5), 278-291.


Kulkarni SK & Dhir A. (2010). Berberine: a plant alkaloid with therapeutic potential for central nervous system disorders. Phytotherapy Research, 24(3):317–324.


Lau CW, X. Q. Yao XQ, et al. (2001). Cardiovascular actions of berberine. Cardiovascular Drug Reviews, 19(3):234–244.


Li, XL Hu XJ, Wang H, et al. (2012). Molecular spectroscopy evidence for berberine binding to DNA: comparative binding and thermodynamic profile of intercalation. Biomacromolecules, 13(3):873–880.


Lin CC, Ng LT, Hsu FF, Shieh DE, Chiang LC. (2004). Cytotoxic effects of Coptis chinensis and Epimedium sagittatum extracts and their major constituents (berberine, coptisine and icariin) on hepatoma and leukaemia cell growth. Clin Exp Pharmacol Physiol, 31(1-2):65-9.


Mantena SK, Sharma SD, Katiyar SK. (2006). Berberine, a natural product, induces G1-phase cell-cycle arrest and caspase-3-dependent apoptosis in human prostate carcinoma cells. Mol Cancer Ther, 5(2):296-308. doi: 10.1158/1535-7163.MCT-05-0448


Mantena SK, Sharma SD, Katiyar SK. (2006). Berberine inhibits growth, induces G1 arrest and apoptosis in human epidermoid carcinoma A431 cells by regulating Cdki–Cdk-cyclin cascade, disruption of mitochondrial membrane potential and cleavage of caspase 3 and PARP. Carcinogenesis, 27(10):2018-27. doi: 10.1093/carcin/bgl043


Meeran SM, Katiyar S & Katiyar SK. (2008). Berberine-induced apoptosis in human prostate cancer cells is initiated by reactive oxygen species generation. Toxicology and Applied Pharmacology, 229(1):33-43. doi:10.1016/j.taap.2007.12.027


Singh T, Vaid M, Katiyar N, et al. (2011). Berberine, an isoquinoline alkaloid, inhibits melanoma cancer cell migration by reducing the expressions of cyclooxygenase-2, prostaglandin E and prostaglandin E receptors. Carcinogenesis, 32(1):86–92.


Sun Y, Xun K, Wang Y, Chen X. (2009). A systematic review of the anti-cancer properties of berberine, a natural product from Chinese herbs. Anti-Cancer Drugs, 20(9):757–769.


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Tang F, Wang D, Duan C, et al. (2009) Berberine inhibits metastasis of nasopharyngeal carcinoma 5-8F cells by targeting rho kinase-mediated ezrin phosphorylation at threonine 567. Journal of Biological Chemistry, 284(40):27456–27466.


Wang N, Feng Y, Zhu M et al. (2010). Berberine induces autophagic cell death and mitochondrial apoptosis in liver cancer cells: the cellular mechanism. Journal of Cellular Biochemistry, 111(6):1426–1436.


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Youn MJ, So HS, Cho HJ, et al. (2008). Berberine, a natural product, combined with cisplatin enhanced apoptosis through a mitochondria/caspase-mediated pathway in HeLa cells. Biological and Pharmaceutical Bulletin, 31(5):789–795.


Yu HH, Kim KJ, Cha JD, et al. (2005). Antimicrobial activity of berberine alone and in combination with ampicillin or oxacillin against methicillin-resistant Staphylococcus aureus. Journal of Medicinal Food, 8(4):454–461.

Thymoquinone

Cancer: Osteosarcoma, pancreatic, colorectal., lung, liver, melanoma, breast

Action: Anti-inflammatory

For centuries, the black seed (Nigella sativa (L.)) herb and oil have been used in Asia, Middle East and Africa to promote health and fight disease. Thymoquinone (TQ) is the major phytochemical constituent of Nigella sativa (L.) oil extract. Phytochemical compounds are emerging as a new generation of anti-cancer agents with limited toxicity in cancer patients.

Osteosarcoma

The anti-proliferative and pro-apoptotic effects of TQ were evaluated in two human osteosarcoma cell lines with different p53 mutation status. TQ decreased cell survival dose-dependently and, more significantly, in p53-null MG63 cells (IC(50) = 17 muM) than in p53-mutant MNNG/HOS cells (IC(50) = 38 muM). Cell viability was reduced more selectively in MG63 tumor cells than in normal human osteoblasts.

It was therefore suggested that the resistance of MNNG/HOS cells to drug-induced apoptosis is caused by the up-regulation of p21(WAF1) by the mutant p53 (transcriptional activity was shown by p53 siRNA treatment) which induces cell-cycle arrest and allows repair of DNA damage.

Collectively, these findings show that TQ induces p53-independent apoptosis in human osteosarcoma cells. As the loss of p53 function is frequently observed in osteosarcoma patients, these data suggest the potential clinical usefulness of TQ for the treatment of these malignancies (Roepke et al., 2007).

Pancreatic Ductal Adenocarcinoma

Inflammation has been identified as a significant factor in the development of solid tumor malignancies. It has recently been shown that thymoquinone (Tq) induces apoptosis and inhibited proliferation in PDA cells. The effect of Tq on the expression of different pro-inflammatory cytokines and chemokines was analyzed by real-time polymerase chain reaction (PCR). Tq dose- and time-dependently significantly reduced PDA cell synthesis of MCP-1, TNF-alpha, interleukin (IL)-1beta and Cox-2. Tq also inhibited the constitutive and TNF-alpha-mediated activation of NF-kappaB in PDA cells and reduced the transport of NF-kappaB from the cytosol to the nucleus. Our data demonstrate previously undescribed anti-inflammatory activities of Tq in PDA cells, which are paralleled by inhibition of NF-kappaB. Tq as a novel inhibitor of pro-inflammatory pathways provides a promising strategy that combines anti-inflammatory and pro-apoptotic modes of action (Chehl et al., 2009).

Lung cancer, Hepatoma, Melanoma, Colon Cancer, Breast Cancer

The potential impact of thymoquinone (TQ) was investigated on the survival., invasion of cancer cells in vitro, and tumor growth in vivo. Exposure of cells derived from lung (LNM35), liver (HepG2), colon (HT29), melanoma (MDA-MB-435), and breast (MDA-MB-231 and MCF-7) tumors to increasing TQ concentrations resulted in a significant inhibition of viability through the inhibition of Akt phosphorylation leading to DNA damage and activation of the mitochondrial-signaling pro-apoptotic pathway. Administration of TQ (10 mg/kg/i.p.) for 18 days inhibited the LNM35 tumor growth by 39% (P < 0.05). Tumor growth inhibition was associated with significant increase in the activated caspase-3. In this context, it has been demonstrated that TQ treatment resulted in a significant inhibition of HDAC2 proteins. In view of the available experimental findings, it is contended that thymoquinone and/or its analogues may have clinical potential as an anti-cancer agent alone or in combination with chemotherapeutic drugs such as cisplatin (Attoub et al., 2012).

Colon Cancer

It was reported that TQ inhibits the growth of colon cancer cells which was correlated with G1 phase arrest of the cell-cycle. Furthermore, TUNEL staining and flow cytometry analysis indicate that TQ triggers apoptosis in a dose- and time-dependent manner. These results indicate that TQ is anti-neoplastic and pro-apoptotic against colon cancer cell line HCT116. The apoptotic effects of TQ are modulated by Bcl-2 protein and are linked to and dependent on p53. Our data support the potential for using the agent TQ for the treatment of colon cancer (Gali-Muhtasib et al., 2004).

References

Attoub S, Sperandio O, Raza H, et al. (2012). Thymoquinone as an anti-cancer agent: evidence from inhibition of cancer cells viability and invasion in vitro and tumor growth in vivo. Fundam Clin Pharmacol, 27(5):557-569. doi: 10.1111/j.1472-8206.2012.01056.x


Chehl N, Chipitsyna G, Gong Q, Yeo CJ, Arafat HA. (2009). Anti-inflammatory effects of the Nigella sativa seed extract, thymoquinone, in pancreatic cancer cells. HPB (Oxford), 11(5):373-81. doi: 10.1111/j.1477-2574.2009.00059.x.


Gali-Muhtasib H, Diab-Assaf M, Boltze C, et al. (2004). Thymoquinone extracted from black seed triggers apoptotic cell death in human colorectal cancer cells via a p53-dependent mechanism. Int J Oncol, 25(4):857-66


Roepke M, Diestel A, Bajbouj K, et al. (2007). Lack of p53 augments thymoquinone-induced apoptosis and caspase activation in human osteosarcoma cells. Cancer Biol Ther, 6(2):160-9.

Thymoquinone

Cancer: Osteosarcoma, pancreatic, colorectal., lung, liver, melanoma, breast

Action: Anti-inflammatory

For centuries, the black seed (Nigella sativa (L.)) herb and oil have been used in Asia, Middle East and Africa to promote health and fight disease. Thymoquinone (TQ) is the major phytochemical constituent of Nigella sativa (L.) oil extract. Phytochemical compounds are emerging as a new generation of anti-cancer agents with limited toxicity in cancer patients.

Osteosarcoma

The anti-proliferative and pro-apoptotic effects of TQ were evaluated in two human osteosarcoma cell lines with different p53 mutation status. TQ decreased cell survival dose-dependently and, more significantly, in p53-null MG63 cells (IC(50) = 17 muM) than in p53-mutant MNNG/HOS cells (IC(50) = 38 muM). Cell viability was reduced more selectively in MG63 tumor cells than in normal human osteoblasts.

It was therefore suggested that the resistance of MNNG/HOS cells to drug-induced apoptosis is caused by the up-regulation of p21(WAF1) by the mutant p53 (transcriptional activity was shown by p53 siRNA treatment) which induces cell-cycle arrest and allows repair of DNA damage.

Collectively, these findings show that TQ induces p53-independent apoptosis in human osteosarcoma cells. As the loss of p53 function is frequently observed in osteosarcoma patients, these data suggest the potential clinical usefulness of TQ for the treatment of these malignancies (Roepke et al., 2007).

Pancreatic Ductal Adenocarcinoma

Inflammation has been identified as a significant factor in the development of solid tumor malignancies. It has recently been shown that thymoquinone (Tq) induces apoptosis and inhibited proliferation in PDA cells. The effect of Tq on the expression of different pro-inflammatory cytokines and chemokines was analyzed by real-time polymerase chain reaction (PCR). Tq dose- and time-dependently significantly reduced PDA cell synthesis of MCP-1, TNF-alpha, interleukin (IL)-1beta and Cox-2. Tq also inhibited the constitutive and TNF-alpha-mediated activation of NF-kappaB in PDA cells and reduced the transport of NF-kappaB from the cytosol to the nucleus. Our data demonstrate previously undescribed anti-inflammatory activities of Tq in PDA cells, which are paralleled by inhibition of NF-kappaB. Tq as a novel inhibitor of pro-inflammatory pathways provides a promising strategy that combines anti-inflammatory and pro-apoptotic modes of action (Chehl et al., 2009).

Lung cancer, Hepatoma, Melanoma, Colon Cancer, Breast Cancer

The potential impact of thymoquinone (TQ) was investigated on the survival., invasion of cancer cells in vitro, and tumor growth in vivo. Exposure of cells derived from lung (LNM35), liver (HepG2), colon (HT29), melanoma (MDA-MB-435), and breast (MDA-MB-231 and MCF-7) tumors to increasing TQ concentrations resulted in a significant inhibition of viability through the inhibition of Akt phosphorylation leading to DNA damage and activation of the mitochondrial-signaling pro-apoptotic pathway. Administration of TQ (10 mg/kg/i.p.) for 18 days inhibited the LNM35 tumor growth by 39% (P < 0.05). Tumor growth inhibition was associated with significant increase in the activated caspase-3. In this context, it has been demonstrated that TQ treatment resulted in a significant inhibition of HDAC2 proteins. In view of the available experimental findings, it is contended that thymoquinone and/or its analogues may have clinical potential as an anti-cancer agent alone or in combination with chemotherapeutic drugs such as cisplatin (Attoub et al., 2012).

Colon Cancer

It was reported that TQ inhibits the growth of colon cancer cells which was correlated with G1 phase arrest of the cell-cycle. Furthermore, TUNEL staining and flow cytometry analysis indicate that TQ triggers apoptosis in a dose- and time-dependent manner. These results indicate that TQ is anti-neoplastic and pro-apoptotic against colon cancer cell line HCT116. The apoptotic effects of TQ are modulated by Bcl-2 protein and are linked to and dependent on p53. Our data support the potential for using the agent TQ for the treatment of colon cancer (Gali-Muhtasib et al., 2004).

References

Attoub S, Sperandio O, Raza H, et al. (2012). Thymoquinone as an anti-cancer agent: evidence from inhibition of cancer cells viability and invasion in vitro and tumor growth in vivo. Fundam Clin Pharmacol, 27(5):557-569. doi: 10.1111/j.1472-8206.2012.01056.x


Chehl N, Chipitsyna G, Gong Q, Yeo CJ, Arafat HA. (2009). Anti-inflammatory effects of the Nigella sativa seed extract, thymoquinone, in pancreatic cancer cells. HPB (Oxford), 11(5):373-81. doi: 10.1111/j.1477-2574.2009.00059.x.


Gali-Muhtasib H, Diab-Assaf M, Boltze C, et al. (2004). Thymoquinone extracted from black seed triggers apoptotic cell death in human colorectal cancer cells via a p53-dependent mechanism. Int J Oncol, 25(4):857-66


Roepke M, Diestel A, Bajbouj K, et al. (2007). Lack of p53 augments thymoquinone-induced apoptosis and caspase activation in human osteosarcoma cells. Cancer Biol Ther, 6(2):160-9.

Luteolin

Cancer: Colorectal., pancreatic, ovarian, breast

Action: Anti-inflammatory, radio-protective, TAM chemo-sensitizer

Luteolin is a flavonoid found in many plants and foods, including Terminalia chebula (Retz.), Prunella vulgaris (L.) and Perilla frutescens [(L.) Britton].

Luteolin is contained in Ocimum sanctum L. or Ocimum tenuiflorum L, commonly known as Holy Basil in English or Tulsi in various Indian languages; it is an important medicinal plant in the various traditional and folk systems of medicine in Southeast Asia. Scientific studies have shown it to possess anti-inflammatory, anti-analgesic, anti-pyretic, anti-diabetic, hepato-protective, hypolipidemic, anti-stress, and immunomodulatory activities. It has been found to prevent chemical-induced skin, liver, oral., and lung cancers and mediates these effects by increasing the anti-oxidant activity, altering the gene expressions, inducing apoptosis, and inhibiting angiogenesis and metastasis.

Radio-protective

The aqueous extract of Tulsi has been shown to protect mice against γ-radiation-induced sickness and mortality and to selectively protect the normal tissues against the tumoricidal effects of radiation. The chemo-preventive and radio-protective properties of Tulsi emphasize aspects that warrant future research to establish its activity and utility in cancer prevention and treatment (Baliga et al., 2013).

Anti-inflammatory

Pre-treatment of RAW 264.7 with luteolin, luteolin-7-glucoside, quercetin, and the isoflavonoid genistein inhibited both the LPS-stimulated TNF-αand interleukin-6 release, whereas eriodictyol and hesperetin only inhibited TNF-αrelease. From the compounds tested luteolin and quercetin were the most potent in inhibiting cytokine production with an IC50 of less than 1 and 5 µM for TNF-αrelease, respectively. Pre-treatment of the cells with luteolin attenuated LPS-induced tyrosine phosphorylation of many discrete proteins. Luteolin inhibited LPS-induced phosphorylation of Akt. Treatment of macrophages with LPS resulted in increased IκB-αphosphorylation and reduced the levels of IκB-α. It was concluded that luteolin inhibits protein tyrosine phosphorylation, nuclear factor-κB-mediated gene expression and pro-inflammatory cytokine production in murine macrophages (Xagorari et al., 2001).

Luteolin (Lut) possesses significant anti-inflammatory activity in well established models of acute and chronic inflammation, such as xylene-induced ear edema in mice (ED50= 107 mg/ kg), carrageenin-induced swellingof the ankle, acetic acid-induced pleurisy and croton oil-induced gaseous pouch granuloma in rats. Its combined immunostimulatory and anti-inflammatory activity, and inhibitory effect upon immediate hypersensitive response provide the pharmacologic bases for the beneficial effects of Lut in the treatment of chronic bronchitis (Chen et al., 1986).

Anti-inflammatory; Lung

Luteolin dose-dependently inhibited the expression and production of nitric oxide (NO) and prostaglandin E2 (PGE2), as well as the expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). Luteolin also reduced the DNA binding activity of nuclear factor-kappa B (NF-κB) in LPS-activated macrophages. Moreover, luteolin blocked the degradation of IκB-α and nuclear translocation of NF-κB p65 subunit.

In sum, these data suggest that, by blocking NF-κ>B and AP-1 activation, luteolin acts to suppress the LPS-elicited inflammatory events in mouse alveolar macrophages, and this effect was mediated, at least in part, by inhibiting the generation of reactive oxygen species. These observations suggest a possible therapeutic application of this agent for treating inflammatory disorders in the lung (Chen et al., 2007).

Anti-inflammatory; Neuroinflammation

Pre-treatment of primary murine microglia and BV-2 microglial cells with luteolin inhibited LPS-stimulated IL-6 production at both the mRNA and protein levels. Whereas luteolin had no effect on the LPS-induced increase in NF-κB DNA binding activity, it markedly reduced AP-1 transcription factor binding activity. To determine whether luteolin might have similar effects in vivo, mice were provided drinking water supplemented with luteolin for 21 days and then they were injected i.p. with LPS. Luteolin consumption reduced LPS-induced IL-6 in plasma 4 hours after injection. Taken together, these data suggest luteolin inhibits LPS-induced IL-6 production in the brain by inhibiting the JNK signaling pathway and activation of AP-1 in microglia. Thus, luteolin may be useful for mitigating neuroinflammation (Jang et al., 2008).

Colon Cancer

Activities of CDK4 and CDK2 decreased within 2 hours after luteolin treatment, with a 38% decrease in CDK2 activity (P < 0.05) observed in cells treated with 40 µmol/l luteolin. Luteolin inhibited CDK2 activity in a cell-free system, suggesting that it directly inhibits CDK2.

tLuteolin promoted G2/M arrest at 24 hours post-treatment  by down-regulating cyclin B1 expression and inhibiting cell division cycle (CDC)2 activity. Luteolin promoted apoptosis with increased activation of caspases 3, 7, and 9 and enhanced poly(ADP-ribose) polymerase cleavage and decreased expression of p21CIP1/WAF1, survivin, Mcl-1, Bcl-xL, and Mdm-2. Decreased expression of these key antiapoptotic proteins could contribute to the increase in p53-independent apoptosis that was observed in HT-29 cells. Lim et al., (2007) demonstrated that luteolin promotes both cell-cycle arrest and apoptosis in the HT-29 colon cancer cell line, providing insight about the mechanisms underlying its anti-tumorigenic activities.

Pancreatic Cancer; Chemotherapy

Simultaneous treatment or pre-treatment (0, 6, 24 and 42 hours) of flavonoids and chemotherapeutic drugs and various concentrations (0-50µM) were assessed using the MTS cell proliferation assay. Simultaneous treatment with either flavonoid (0,13, 25 or 50µM) and chemotherapeutic drugs 5-fluorouracil (5-FU, 50µM) or gemcitabine (Gem, 10µM) for 60h resulted in less-than-additive effect (p<0.05). Pre-treatment for 24 hours with 13µM of either Api or Lut, followed by Gem for 36 hours was optimal to inhibit cell proliferation.

Pre-treatment of cells with 11-19µM of either flavonoid for 24 hours resulted in 59-73% growth inhibition when followed by Gem (10µM, 36h). Lut (15µM, 24h) Pre-treatment followed by Gem (10µM, 36h), significantly decreased protein expression of nuclear GSK-3βand NF-κB p65 and increased pro-apoptotic cytosolic cytochrome c. Pre-treatment of human pancreatic cancer cells BxPC-3 with low concentrations of Lut effectively aid in the anti-proliferative activity of chemotherapeutic drugs (Johnson et al., 2013).

Ovarian Cancer

Luteolin has been found to repress NF-kappaB (NF-κ>B, a pro-inflammatory transcription factor) and inhibit pro-inflammatory cytokines such as TNF-αand IL-6. Additionally, it has been shown to stabilize p53 protein, sensitize TRAIL (TNF receptor apoptosis-inducing ligand) induced apoptosis, and prevent or delay chemotherapy-resistance.

Recent studies further indicate that luteolin potently inhibits VEGF production and suppresses ovarian cancer cell metastasis in vitro. Lastly, oridonin and wogonin were suggested to suppress ovarian CSCs as is reflected by down-regulation of the surface marker EpCAM. Unlike NSAIDS (non-steroid anti-inflammatory drugs), well documented clinical data for phyto-active compounds are lacking. In order to evaluate objectively the potential benefit of these compounds in the treatment of ovarian cancer, strategically designed, large scale studies are warranted (Chen et al., 2012).

Chemo-sensitizer

The sensitization effect of luteolin on cisplatin-induced apoptosis is p53 dependent, as such effect is only found in p53 wild-type cancer cells but not in p53 mutant cancer cells. Moreover, knockdown of p53 by small interfering RNA made p53 wild-type cancer cells resistant to luteolin and cisplatin. Second, Shi et al., (2007) observed a significant increase of p53 protein level in luteolin-treated cancer cells without increase of p53 mRNA level, indicating the possible effect of luteolin on p53 posttranscriptional regulation.

In summary, data from this study reveal a novel molecular mechanism involved in the anti-cancer effect of luteolin and support its potential clinical application as a chemo-sensitizer in cancer therapy.

Breast Cancer; TAM Chemo-sensitizer

This study found that the level of cyclin E2 (CCNE2) mRNA was higher in tumor cells (4.89-fold, (∗)P=0.005) than in normal paired tissue samples as assessed using real-time reverse-transcriptase polymerase chain reaction (RT-PCR) analysis (n=257). Further, relatively high levels of CCNE2 protein expression were detected in tamoxifen-resistant (TAM-R) MCF-7 cells.

These results showed that the level of CCNE2 protein expression was specifically inhibited in luteolin-treated (5µM) TAM-R cells, either in the presence or absence of 4-OH-TAM (100nM). Combined treatment with 4-OH-TAM and luteolin synergistically sensitized the TAM-R cells to 4-OH-TAM. The results of this study suggest that luteolin can be used as a chemo-sensitizer to target the expression level of CCNE2 and that it could be a novel strategy to overcome TAM resistance in breast cancer patients (Tu et al., 2013).

References

Baliga MS, Jimmy R, Thilakchand KR, et al. (2013). Ocimum sanctum L (Holy Basil or Tulsi) and its phytochemicals in the prevention and treatment of cancer. Nutr Cancer, 65(1):26-35. doi: 10.1080/01635581.2013.785010.


Chen CY, Peng WH, Tsai KD and Hsu SL. (2007). Luteolin suppresses inflammation-associated gene expression by blocking NF-κB and AP-1 activation pathway in mouse alveolar macrophages. Life Sciences, 81(23-24):1602-1614. doi:10.1016/j.lfs.2007.09.028


Chen MZ, Jin WZ, Dai LM, Xu SY. (1986). Effect of luteolin on inflammation and immune function. Chinese Journal of Pharmacology and Toxicology, 1986-01.


Chen SS, Michael A, Butler-Manuel SA. (2012). Advances in the treatment of ovarian cancer: a potential role of anti-inflammatory phytochemicals. Discov Med, 13(68):7-17.


Jang S, Kelley KW, Johnson RW. (2008). Luteolin reduces IL-6 production in microglia by inhibiting JNK phosphorylation and activation of AP-1. PNAS, 105(21):7534-7539


Johnson JL, Gonzalez de Mejia E. (2013). Interactions between dietary flavonoids apigenin or luteolin and chemotherapeutic drugs to potentiate anti-proliferative effect on human pancreatic cancer cells, in vitro. Food Chem Toxicol, S0278-6915(13)00491-2. doi: 10.1016/j.fct.2013.07.036.


Lim DY, Jeong Y, Tyner Al., Park JHY. (2007). Induction of cell-cycle arrest and apoptosis in HT-29 human colon cancer cells by the dietary compound luteolin. Am J Physiol Gastrointest Liver Physiol, 292: G66-G75. doi:10.1152/ajpgi.00248.2006.


Shi R, Huang Q, Zhu X, et al. (2007). Luteolin sensitizes the anti-cancer effect of cisplatin via c-Jun NH2-terminal kinase-mediated p53 phosphorylation and stabilization. Molecular Cancer Therapeutics, 6(4):1338-1347. doi: 10.1158/1535-7163.MCT-06-0638.


Tu SH, Ho CT, Liu MF, et al. (2013). Luteolin sensitizes drug-resistant human breast cancer cells to tamoxifen via the inhibition of cyclin E2 expression. Food Chem, 141(2):1553-61. doi: 10.1016/j.foodchem.2013.04.077.


Xagorari A, Papapetropoulos A, Mauromatis A, et al. (2001). Luteolin inhibits an endotoxin-stimulated phosphorylation cascade and pro-inflammatory cytokine production in macrophages. JPET, 296(1):181-187.

Carnosol

Cancer: Breast, prostate, skin, colon, leukemia, stomach

Action: Anti-inflammatrory, anti-angiogenic

Carnosol is found in certain Mediterranean meats, fruits, vegetables, and olive oil. In particular, it is sourced from rosemary (Rosmarinus officinalis (L.)) and desert sage (Salvia pachyphylla (Epling ex Munz)).

Prostate Cancer, Breast Cancer, Skin Cancer, Colon Cancer, Leukemia

One agent, carnosol, has been evaluated for anti-cancer property in prostate, breast, skin, leukemia, and colon cancer with promising results. These studies have provided evidence that carnosol targets multiple deregulated pathways associated with inflammation and cancer that include nuclear factor kappa B (NFκB), apoptotic related proteins, phosphatidylinositol-3-kinase (PI3 K)/Akt, androgen and estrogen receptors, as well as molecular targets. In addition, carnosol appears to be well tolerated in that it has a selective toxicity towards cancer cells versus non-tumorigenic cells and is well tolerated when administered to animals.

This mini-review reports on the pre-clinical studies that have been performed to date with carnosol describing mechanistic, efficacy, and safety/tolerability studies as a cancer chemoprevention and anti-cancer agent (Johnson, 2011).

Literature evidence from animal and cell culture studies demonstrates the anti-cancer potential of rosemary extract, carnosol, carnosic acid, ursolic acid, and rosmarinic acid to suppress the development of tumors in several organs including the colon, breast, liver, stomach, as well as melanoma and leukemia cells (Ngo et al., 2011).

Anti-inflammatory

Treatment with retinoic acid (RA) or carnosol, two structurally unrelated compounds with anti-cancer properties, inhibited phorbol ester (PMA)-mediated induction of activator protein-1 (AP-1) activity and cyclooxygenase-2 (COX-2) expression in human mammary epithelial cells. Treatment with carnosol but not RA blocked increased binding of AP-1 to the COX-2 promoter. Carnosol but not RA inhibited the activation of PKC, ERK1/2, p38, and c-Jun NH2-terminal kinase mitogen-activated protein kinase. Overexpressing c-Jun but not CBP/p300 reversed the suppressive effect of carnosol on PMA-mediated stimulation of COX-2 promoter activity.

Carnosol inhibited the induction of COX-2 by blocking PKC signaling and thereby the binding of AP-1 to the CRE of the COX-2 promoter. Taken together, these results show that small molecules can block the activation of COX-2 transcription by distinct mechanisms (Subbaramaiah, 2002).

Breast Cancer

Two rosemary components, carnosol and ursolic acid, appear to be partly responsible for the anti-tumorigenic activity of rosemary. Supplementation of diets for 2 weeks with rosemary extract (0.5% by wt) but not carnosol (1.0%) or ursolic acid (0.5%) resulted in a significant decrease in the in vivo formation of rat mammary DMBA-DNA adducts, compared to controls. When injected intraperitoneally (i.p.) for 5 days at 200 mg/kg body wt, rosemary and carnosol, but not ursolic acid, significantly inhibited mammary adduct formation by 44% and 40%, respectively, compared to controls. Injection of this dose of rosemary and carnosol was associated with a significant 74% and 65% decrease, respectively, in the number of DMBA-induced mammary adenocarcinomas per rat, compared to controls. Ursolic acid injection had no effect on mammary tumorigenesis.

Therefore, carnosol is one rosemary constituent that can prevent DMBA-induced DNA damage and tumor formation in the rat mammary gland, and, thus, has potential for use as a breast cancer chemopreventative agent (Singletary et al., 1996).

Anti-angiogenic

The anti-angiogenic activity of carnosol and carnosic acid could contribute to the chemo-preventive, anti-tumoral and anti-metastatic activities of rosemary extracts and suggests that there is potential in the treatment of other angiogenesis-related malignancies (L-pez-JimŽnez et al., 2013).

References:

Johnson JJ. (2011). Carnosol: A promising anti-cancer and anti-inflammatory agent. Cancer Letters, 305(1):1-7. doi:10.1016/j.canlet.2011.02.005.


L-pez-JimŽnez A, Garc'a-Caballero M, Medina Mç, Quesada AR. (2013). Anti-angiogenic properties of carnosol and carnosic acid, two major dietary compounds from rosemary. Eur J Nutr, 52(1):85-95. doi: 10.1007/s00394-011-0289-x.


Ngo SN, Williams DB, Head RJ. (2011). Rosemary and cancer prevention: preclinical perspectives. Crit Rev Food Sci Nutr, 51(10):946-54. doi: 10.1080/10408398.2010.490883.


Singletary K, MacDonald C & Wallig M. (1996). Inhibition by rosemary and carnosol of 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumorigenesis and in vivo DMBA-DNA adduct formation. Cancer Letters, 104(1):43-8. doi: 10.1016/0304-3835(96)04227-9


Subbaramaiah K, Cole PA, Dannenberg AJ. (2002). Retinoids and Carnosol Suppress Cyclooxygenase-2 Transcription by CREB-binding Protein/p300-dependent and -independent Mechanisms. Cancer Res, 62:2522

Carnosol

Cancer: Breast, prostate, skin, colon, leukemia, stomach

Action: Anti-inflammatrory, anti-angiogenic

Carnosol is found in certain Mediterranean meats, fruits, vegetables, and olive oil. In particular, it is sourced from rosemary (Rosmarinus officinalis (L.)) and desert sage (Salvia pachyphylla (Epling ex Munz)).

Prostate Cancer, Breast Cancer, Skin Cancer, Colon Cancer, Leukemia

One agent, carnosol, has been evaluated for anti-cancer property in prostate, breast, skin, leukemia, and colon cancer with promising results. These studies have provided evidence that carnosol targets multiple deregulated pathways associated with inflammation and cancer that include nuclear factor kappa B (NFκB), apoptotic related proteins, phosphatidylinositol-3-kinase (PI3 K)/Akt, androgen and estrogen receptors, as well as molecular targets. In addition, carnosol appears to be well tolerated in that it has a selective toxicity towards cancer cells versus non-tumorigenic cells and is well tolerated when administered to animals.

This mini-review reports on the pre-clinical studies that have been performed to date with carnosol describing mechanistic, efficacy, and safety/tolerability studies as a cancer chemoprevention and anti-cancer agent (Johnson, 2011).

Literature evidence from animal and cell culture studies demonstrates the anti-cancer potential of rosemary extract, carnosol, carnosic acid, ursolic acid, and rosmarinic acid to suppress the development of tumors in several organs including the colon, breast, liver, stomach, as well as melanoma and leukemia cells (Ngo et al., 2011).

Anti-inflammatory

Treatment with retinoic acid (RA) or carnosol, two structurally unrelated compounds with anti-cancer properties, inhibited phorbol ester (PMA)-mediated induction of activator protein-1 (AP-1) activity and cyclooxygenase-2 (COX-2) expression in human mammary epithelial cells. Treatment with carnosol but not RA blocked increased binding of AP-1 to the COX-2 promoter. Carnosol but not RA inhibited the activation of PKC, ERK1/2, p38, and c-Jun NH2-terminal kinase mitogen-activated protein kinase. Overexpressing c-Jun but not CBP/p300 reversed the suppressive effect of carnosol on PMA-mediated stimulation of COX-2 promoter activity.

Carnosol inhibited the induction of COX-2 by blocking PKC signaling and thereby the binding of AP-1 to the CRE of the COX-2 promoter. Taken together, these results show that small molecules can block the activation of COX-2 transcription by distinct mechanisms (Subbaramaiah, 2002).

Breast Cancer

Two rosemary components, carnosol and ursolic acid, appear to be partly responsible for the anti-tumorigenic activity of rosemary. Supplementation of diets for 2 weeks with rosemary extract (0.5% by wt) but not carnosol (1.0%) or ursolic acid (0.5%) resulted in a significant decrease in the in vivo formation of rat mammary DMBA-DNA adducts, compared to controls. When injected intraperitoneally (i.p.) for 5 days at 200 mg/kg body wt, rosemary and carnosol, but not ursolic acid, significantly inhibited mammary adduct formation by 44% and 40%, respectively, compared to controls. Injection of this dose of rosemary and carnosol was associated with a significant 74% and 65% decrease, respectively, in the number of DMBA-induced mammary adenocarcinomas per rat, compared to controls. Ursolic acid injection had no effect on mammary tumorigenesis.

Therefore, carnosol is one rosemary constituent that can prevent DMBA-induced DNA damage and tumor formation in the rat mammary gland, and, thus, has potential for use as a breast cancer chemopreventative agent (Singletary et al., 1996).

Anti-angiogenic

The anti-angiogenic activity of carnosol and carnosic acid could contribute to the chemo-preventive, anti-tumoral and anti-metastatic activities of rosemary extracts and suggests that there is potential in the treatment of other angiogenesis-related malignancies (L-pez-JimŽnez et al., 2013).

References:

Johnson JJ. (2011). Carnosol: A promising anti-cancer and anti-inflammatory agent. Cancer Letters, 305(1):1-7. doi:10.1016/j.canlet.2011.02.005.


L-pez-JimŽnez A, Garc'a-Caballero M, Medina Mç, Quesada AR. (2013). Anti-angiogenic properties of carnosol and carnosic acid, two major dietary compounds from rosemary. Eur J Nutr, 52(1):85-95. doi: 10.1007/s00394-011-0289-x.


Ngo SN, Williams DB, Head RJ. (2011). Rosemary and cancer prevention: preclinical perspectives. Crit Rev Food Sci Nutr, 51(10):946-54. doi: 10.1080/10408398.2010.490883.


Singletary K, MacDonald C & Wallig M. (1996). Inhibition by rosemary and carnosol of 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumorigenesis and in vivo DMBA-DNA adduct formation. Cancer Letters, 104(1):43-8. doi: 10.1016/0304-3835(96)04227-9


Subbaramaiah K, Cole PA, Dannenberg AJ. (2002). Retinoids and Carnosol Suppress Cyclooxygenase-2 Transcription by CREB-binding Protein/p300-dependent and -independent Mechanisms. Cancer Res, 62:2522

Baicalin & Baicalein

Cancer:
Myeloma, liver, colorectal., breast, prostate, oral., hepatoma, ovarian

Action: Anti-cancer, cardiovascular disease, cytostatic, cardio-protective against Doxorubicin, anti-inflammatory, angiogenesis

Baicalin and baicalein are naturally occurring flavonoids that are found in the roots and leaves of some Chinese medicinal plants (including Scutellaria radix, Scutellaria rivularis (Benth.); Scutellaria baicalensis (Georgi) and Scutellaria lateriflora (L.)) are thought to have anti-oxidant activity and possible anti-angiogenic, anti-cancer, anxiolytic, anti-inflammatory and neuroprotective activities. In particular, Scutellaria baicalensis is one of the most popular and multi-purpose herbs used in China traditionally for treatment of inflammation, hypertension, cardiovascular diseases, and bacterial and viral infections (Ye et al., 2002; Zhang et al., 2011a).

Anti-cancer

Accumulating evidence demonstrates that Scutellaria also possesses potent anti-cancer activities. The bioactive components of Scutellaria have been confirmed to be flavones, wogonin, baicalein and baicalin. These phytochemicals are not only cytostatic but also cytotoxic to various human tumor cell lines in vitro and inhibit tumor growth in vivo. Most importantly, they show almost no or minor toxicity to normal epithelial and normal peripheral blood and myeloid cells. The anti-tumor functions of these flavones are largely due to their abilities to scavenge oxidative radicals, to attenuate NF-kappaB activity, to inhibit several genes important for regulation of the cell-cycle, to suppress COX-2 gene expression and to prevent viral infections (Li, 2008).

Multiple Myeloma

In the search for a more effective adjuvant therapy to treat multiple myeloma (MM), Ma et al. (2005) investigated the effects of the traditional Chinese herbal medicines Huang-Lian-Jie-Du-Tang (HLJDT), Gui-Zhi-Fu-Ling-Wan (GZFLW), and Huang-Lian-Tang (HLT) on the proliferation and apoptosis of myeloma cells. HLJDT inhibited the proliferation of myeloma cell lines and the survival of primary myeloma cells, especially MPC-1- immature myeloma cells, and induced apoptosis in myeloma cell lines via a mitochondria-mediated pathway by reducing mitochondrial membrane potential and activating caspase-9 and caspase-3.

Further experiments confirmed that Scutellaria radix was responsible for the suppressive effect of HLJDT on myeloma cell proliferation, and the baicalein in Scutellaria radix showed strong growth inhibition and induction of apoptosis in comparison with baicalin or wogonin. Baicalein as well as baicalin suppressed the survival in vitro of MPC-1- immature myeloma cells rather than MPC-1+ myeloma cells from myeloma patients.

Baicalein inhibited the phosphorylation of IkB-alpha, which was followed by decreased expression of the IL-6 and XIAP genes and activation of caspase-9 and caspase-3. Therefore, HLJDT and Scutellaria radix have an anti-proliferative effect on myeloma cells, especially MPC-1- immature myeloma cells, and baicalein may be responsible for the suppressive effect of Scutellaria radix by blocking IkB-alpha degradation (Ma, 2005).

Hepatoma

The effects of the flavonoids from Scutellaria baicalensis Georgi (baicalein, baicalin and wogonin) in cultured human hepatoma cells (Hep G2, Hep 3B and SK-Hep1) were compared by MTT assay and flow cytometry. All three flavonoids dose-dependently decreased the cell viabilities accompanying the collapse of mitochondrial membrane potential and the depletion of glutathione content. However, the influence of baicalein, baicalin or wogonin on cell-cycle progression was different.

All three flavonoids resulted in prominent increase of G2/M population in Hep G2 cells, whereas an accumulation of sub G1 (hypoploid) peak in Hep 3B cells was observed. In SK-Hep1 cells, baicalein and baicalin resulted in a dramatic boost in hypoploid peak, but wogonin mainly in G1 phase accumulation. These data, together with the previous findings in other hepatoma cell lines, suggest that baicalein, baicalin and wogonin might be effective candidates for inducing apoptosis or inhibiting proliferation in various human hepatoma cell lines (Chang, 2002).

Long dan xie gan tang (pinyin) is one of the most commonly used herbal formulas by patients with chronic liver disease in China. Accumulated anecdotal evidence suggests that Long dan tang may have beneficial effects in patients with hepatocellular carcinoma. Long dan tang is comprised of five herbs: Gentiana root, Scutellaria root, Gardenia fruit, Alisma rhizome, and Bupleurum root. The cytotoxic effects of compounds from the five major ingredients isolated from the above plants, i.e. gentiopicroside, baicalein, geniposide, alisol B acetate and saikosaponin-d, were investigated, respectively, on human hepatoma Hep3B cells..

Interestingly, baicalein by itself induced an increase in H(2)O(2) generation and the subsequent NF-kappaB activation; furthermore, it effectively inhibited the transforming growth factor-beta(1) (TGF-beta(1))-induced caspase-3 activation and cell apoptosis. Results suggest that alisol B acetate and saikosaponin-d induced cell apoptosis through the caspase-3-dependent and -independent pathways, respectively. Instead of inducing apoptosis, baicalein inhibits TGF-beta(1)-induced apoptosis via increase in cellular H(2)O(2) formation and NF-kappaB activation in human hepatoma Hep3B cells (Chou, Pan, Teng & Guh, 2003).

Ovarian Cancer

Ovarian cancer is one of the primary causes of death for women all through the Western world. Two kinds of ovarian cancer (OVCAR-3 and CP-70) cell lines and a normal ovarian cell line (IOSE-364) were selected to be investigated in the inhibitory effect of baicalin and baicalein on cancer cells. Largely, baicalin and baicalein inhibited ovarian cancer cell viability in both ovarian cancer cell lines with LD50 values in the range of 45-55 µM for baicalin and 25-40 µM for baicalein. On the other hand, both compounds had fewer inhibitory effects on normal ovarian cells viability with LD50 values of 177 µM for baicalin and 68 µM for baicalein.

Baicalin decreased expression of VEGF (20 µM), cMyc (80 µM), and NFkB (20 µM); baicalein decreased expression of VEGF (10 µM), HIF-1α (20 µM), cMyc (20 µM), and NFkB (40 µM). Therefore baicalein is more effective in inhibiting cancer cell viability and expression of VEGF, HIF-1α, cMyc, and NFκB in both ovarian cancer cell lines. It seems that baicalein inhibited cancer cell viability through the inhibition of cancer promoting genes expression including VEGF, HIF-1α, cMyc, and NFκB.

Overall, this study showed that baicalein and baicalin significantly inhibited the viability of ovarian cancer cells, while generally exerting less of an effect on normal cells. They have potential for chemoprevention and treatment of ovarian cancers (Chen, 2013).

Breast Cancer

Baicalin was found to be a potent inhibitor of mammary cell line MCF-7 and ductal breast epithelial tumor cell line T-47D proliferation, as well as having anti-proliferative effects on other cancer types such as the human head and neck cancer epithelial cell lines CAL-27 and FaDu. Overall, baicalin inhibited the proliferation of human breast cancer cells and CAL-27 and FaDu cells with effective potency (Franek, 2005).

Breast Cancer, Cell Invasion

The effect of Baicalein on cell viability of the human breast cancer MDA-MB-231 cell line was tested by MTT. 50, 100 µmol·L-1 of Baicalein inhibited significantly cell invasion(P0.01) and migration(P0.01) compared with control groups. The inhibitory rates were 50% and 77% in cell migration and 15% and 44% in cell invasion, respectively. 50 µmol·L-1 of Baicalein significantly inhibited the level of MMP 2 expression. 100 µmol·L-1 of Baicalein significantly inhibited the level of MMP 9 and uPA expressions.

Baicalein inhibits invasion and migration of MDA-MB-231 cells. The mechanisms may be involved in the direct inhibition of cell invasion and migration abilities, and the inhibition of MMP 2, MMP 9, and uPA expressions (Wang et al., 2010).

The proliferation of MDA-MB-231 cell line human breast adenocarcinoma was inhibited by baicalin in a dose-and time-dependent manner and the IC50 was 151 µmol/L. The apoptotic rate of the baicalin-treated MDA-MB-231 cells increased significantly at 48 hours. Flow cytometer analysis also revealed that most of the baicalin-treated MDA-MB-231 cells were arrested in the G2/M phase. Typically apoptotic characteristics such as condensed chromatin and apoptotic bodies were observed after being treated with baicalin for 48 hours.

The results of RT-PCR showed that the expression of bax was up-regulated; meanwhile, the expression of bcl-2 was down-regulated. Baicalin could inhibit the proliferation of MDA-MB-231 cells through apoptosis by regulating the expression of bcl-2, bax and intervening in the process of the cell-cycle (Zhu et al., 2008).

Oral Cancer

As an aryl hydrocarbon receptor (AhR) ligand, baicalein at high concentrations blocks AhR-mediated dioxin toxicity. Because AhR had been reported to play a role in regulating the cell-cycle, it is suspected that the anti-cancer effect of baicalein is associated with AhR. The molecular mechanism involved in the anti-cancer effect of baicalein in oral cancer cells HSC-3 has been investigated, including whether such an effect would be AhR-mediated. Results revealed that baicalein inhibited cell proliferation and increased AhR activity in a dose-dependent manner. Cell-cycle was arrested at the G1 phase and the expression of CDK4, cyclin D1, and phosphorylated retinoblastoma (pRb) was decreased.

When cells were pre-treated with LiCl, the inhibitor of GSK-3β, the decrease of cyclin D1 was blocked and the reduction of pRb was recovered. The data indicates that in HSC-3 the reduction of pRb is mediated by baicalein both through activation of AhR and facilitation of cyclin D1 degradation, which causes cell-cycle arrest at the G1 phase, and results in the inhibition of cell proliferation (Cheng, 2012).

Anti-inflammatory

Baicalin has also been examined for its effects on LPS-induced nitric oxide (NO) production and iNOS and COX-2 gene expressions in RAW 264.7 macrophages. The results indicated that baicalin inhibited LPS-induced NO production in a concentration-dependent manner without a notable cytotoxic effect on these cells. The decrease in NO production was consistent with the inhibition by baicalin of LPS-induced iNOS gene expression (Chen, 2001)

Angiogenesis Modulation

The modulation of angiogenesis is one possible mechanism by which baicalin may act in the treatment of cardiovascular diseases. This may be elucidated by investigating the effects of baicalin on the expression of vascular endothelial growth factor (VEGF), a critical factor for angiogenesis. The effects of baicalin and an extract of S. baicalensis on VEGF expression were tested in several cell lines. Both agents induced VEGF expression in all cells without increasing expression of hypoxia-inducible factor-1alpha (HIF-1alpha).

Their ability to induce VEGF expression was suppressed once ERRalpha expression was knocked down by siRNA, or ERRalpha-binding sites were deleted in the VEGF promoter. It was also found that both agents stimulated cell migration and vessel sprout formation from the aorta. These results therefore implicate baicalin and S. baicalensis in angiogenesis by inducing VEGF expression through the activation of the ERRalpha pathway (Zhang, 2011b).

Colon Cancer

The compounds of baicalein and wogonin, derived from the Chinese herb Scutellaria baicalensis, were studied for their effect in suppressing the viability of HT-29 human colon cancer cells. Following treatment with baicalein or wogonin, several apoptotic events were observed, including DNA fragmentation, chromatin condensation and increased cell-cycle arrest at the G1 phase. Baicalein and wogonin decreased Bcl-2 expression, whereas the expression of Bax was increased in a dose-dependent manner when compared to the control.

The results indicated that baicalein induced apoptosis via Akt activation, in a p53-dependent manner, in HT-29 colon cancer cells. Baicalein may serve as a chemo-preventive, or therapeutic, agent for HT-29 colon cancer (Kim et al., 2012).

Cardio-protective

The cardiotoxicity of doxorubicin limits its clinical use in the treatment of a variety of malignancies. Previous studies suggest that doxorubicin-associated cardiotoxicity is mediated by reactive oxygen species (ROS)-induced apoptosis. Baicalein attenuated phosphorylation of JNK induced by doxorubicin. Co-treatment of cardiomyocytes with doxorubicin and JNK inhibitor SP600125 (10 µM; 24 hours) reduced JNK phosphorylation and enhanced cell survival., suggesting that the baicalein protection against doxorubicin cardiotoxicity was mediated by JNK activation. Baicalein adjunct treatment confers anti-apoptotic protection against doxorubicin-induced cardiotoxicity without compromising its anti-cancer efficacy (Chang et al., 2011).

Prostate Cancer

There are four compounds capable of inhibiting prostate cancer cell proliferation in Scutellaria baicalensis: baicalein, wogonin, neobaicalein, and skullcapflavone. Comparisons of the cellular effects induced by the entire extract versus the four-compound combination produced comparable cell-cycle changes, levels of growth inhibition, and global gene expression profiles (r(2) = 0.79). Individual compounds exhibited anti-androgenic activities with reduced expression of the androgen receptor and androgen-regulated genes. In vivo, baicalein (20 mg/kg/d p.o.) reduced the growth of prostate cancer xenografts in nude mice by 55% at 2 weeks compared with placebo and delayed the average time for tumors to achieve a volume of approximately 1,000 mm(3) from 16 to 47 days (P < 0.001).

Most of the anti-cancer activities of S. baicalensis can be recapitulated with four purified constituents that function in part through inhibition of the androgen receptor signaling pathway (Bonham et al., 2005)

Cancer: Acute lymphocytic leukemia, lymphoma and myeloma

Action: Cell-cycle arrest, induces apoptosis

Scutellaria baicalensis (S.B.) is a widely used Chinese herbal medicine. S.B inhibited the growth of acute lymphocytic leukemia (ALL), lymphoma and myeloma cell lines by inducing apoptosis and cell cycle arrest at clinically achievable concentrations. The anti-proliferative effectwas associated with mitochondrial damage, modulation of the Bcl family of genes, increased level of the CDK inhibitor p27KIP1 and decreased level of c-myc oncogene. HPLC analysis of S.B. showed it contains 21% baicalin and further studies confirmed it was the major anti-cancer component of S.B. Thus, Scutellaria baicalensis should be tested in clinical trials for these hematopoietic malignancies (Kumagai et al., 2007).

References

Bonham M, Posakony J, Coleman I, Montgomery B, Simon J, Nelson PS. (2005). Characterization of chemical constituents in Scutellaria baicalensis with antiandrogenic and growth-inhibitory activities toward prostate carcinoma. Clin Cancer Res, 11(10):3905-14.


Chang WH Chen CH Lu FJ. (2002). Different Effects of Baicalein, Baicalin and Wogonin on Mitochondrial Function, Glutathione Content and cell-cycle Progression in Human Hepatoma Cell Lines. Planta Med, 68(2):128-32. doi: 10.1055/s-2002-20246


Chang WT, Li J, Huang HH, et al. (2011). Baicalein protects against doxorubicin-induced cardiotoxicity by attenuation of mitochondrial oxidant injury .and JNK activation. J Cell Biochem. doi: 10.1002/jcb.23201.


Chen J, Li Z, Chen AY, Ye X, et al. (2013). Inhibitory effect of baicalin and baicalein on ovarian cancer cells. Int J Mol Sci, 14(3):6012-25. doi: 10.3390/ijms14036012.


Chen YC, Shen SC, Chen LG, Lee TJ, Yang LL. (2001). Wogonin, baicalin, and baicalein inhibition of inducible nitric oxide synthase and cyclooxygenase-2 gene expressions induced by nitric oxide synthase inhibitors and lipopolysaccharide. Biochem Pharmacol,61(11):1417-27. doi:10.1016/S0006-2952(01)00594-9


Cheng YH, Li LA, Lin P, et al. (2012). Baicalein induces G1 arrest in oral cancer cells by enhancing the degradation of cyclin D1 and activating AhR to decrease Rb phosphorylation. Toxicol Appl Pharmacol, 263(3):360-7. doi: 10.1016/j.taap.2012.07.010.


Chou CC, Pan SL, Teng CM, & Guh JH. (2003). Pharmacological evaluation of several major ingredients of Chinese herbal medicines in human hepatoma Hep3B cells. European Journal of Pharmaceutical Sciences, 19(5), 403-12.


Franek KJ, Zhou Z, Zhang WD, Chen WY. (2005). In vitro studies of baicalin alone or in combination with Salvia miltiorrhiza extract as a potential anti-cancer agent. Int J Oncol, 26(1):217-24.


Kim SJ, Kim HJ, Kim HR, et al. (2012). Anti-tumor actions of baicalein and wogonin in HT-29 human colorectal cancer cells. Molecular Medicine Reports, 6(6):1443-1449. doi: 10.3892/mmr.2012.1085.


Li-Weber M. (2009). New therapeutic aspects of flavones: The anti-cancer properties of Scutellaria and its main active constituents Wogonin, Baicalein and Baicalin. Cancer Treat Rev, 35(1):57-68. doi: 10.1016/j.ctrv.2008.09.005.


Ma Z, Otsuyama K, Liu S, et al. (2005). Baicalein, a component of Scutellaria radix from Huang-Lian-Jie-Du-Tang (HLJDT), leads to suppression of proliferation and induction of apoptosis in human myeloma cells. Blood, 105(8):3312-8. doi:10.1182/blood-2004-10-3915.


Wang Xf, Zhou Qm, Su Sb. (2010). Experimental study on Baicalein inhibiting the invasion and migration of human breast cancer cells. Zhong Guo Yao Li Xue Tong Bao, 26(6): 745-750.


Zhang XW, Li WF, Li WW, et al. (2011a). Protective effects of the aqueous extract of Scutellaria baicalensis against acrolein-induced oxidative stress in cultured human umbilical vein endothelial cells. Pharm Biol, 49(3): 256–261. doi:10.3109/13880209.2010.501803.


Ye F, Xui L, Yi J, Zhang, W, Zhang DY. (2002). Anti-cancer activity of Scutellaria baicalensis and its potential mechanism. J Altern Complement Med, 8(5):567-72.


Zhang K, Lu J, Mori T, et al. (2011b). Baicalin increases VEGF expression and angiogenesis by activating the ERR{alpha}/PGC-1{alpha} pathway.[J]. Cardiovascular Research, 89(2):426-435.


Zhu Gq, Tang Lj, Wang L, Su Jj, et al. (2008). Study on Baicalin Induced Apoptosis of Human Breast Cancer Cell Line MDA-MB-231. An Hui Zhong Yi Xue Yuan Xue Bao, 27(2):20-23

Kumagai T, et al. (2007) Scutellaria baicalensis, a herbal medicine: Anti-proliferative and apoptotic activity against acute lymphocytic leukemia, lymphoma and myeloma cell lines. Leukemia Research 31 (2007) 523-530

Mollugin

Cancer: Breast, ovarian

Action: Multi-drug resistance, anti-inflammatory, blocks neurotoxicity

Mollugin originally isolated from Rubia cordifolia (L.) is a pharmacological compound for its anti-inflammation, anti-cancer, and anti-viral activity. Mollugin-caused inhibition of phenacetin O-deethylation was concentration-dependent in hierarchical linear models (HLMs), but not time-dependent. In addition, the Lineweaver-Burk plot indicated a typical competitive inhibition. Inhibitory effects of mollugin on human recombinant cDNA-expressed CYP1A1 and 1A2 were comparable. Taken together, the results suggested that mollugin might cause herb-drug interaction through selective inhibition of CYP1A2 in humans receiving herbal medications, including R. cordifolia (Kim et al., 2013).

MDR, Anti-inflammatory

Mollugin treatment significantly inhibited MDR1 expression by blocking MDR1 transcription. P-glycoprotein (P-gp), an important efflux transporter, is encoded by the MDR1 class of genes and is a central element of the multi-drug resistance (MDR) phenomenon in cancer cells. The suppression of MDR1 promoter activity and protein expression was mediated through mollugin-induced activation of AMP-activated protein kinase (AMPK). Furthermore, mollugin inhibited MDR1 expression through the suppression of NF-κB and cAMP-response element binding protein (CREB) activation. These results suggest that mollugin treatment enhanced suppression of P-gp expression by inhibiting the NF-κB signaling pathway and COX-2 expression, as well as attenuating cAMP-response element (CRE) transcriptional activity through AMPK activation (Tran et al., 2013).

Breast Cancer; Ovarian Cancer

Mollugin exhibited potent inhibitory effects on cancer cell proliferation, especially in HER2-overexpressing SK-BR-3 human breast cancer cells and SK-OV-3 human ovarian cancer cells in a dose- and time-dependent manner without affecting immortalized normal mammary epithelial cell line MCF-10A. Mollugin treatment caused a dose-dependent inhibition of HER2 gene expression at the transcriptional level, potentially in part through suppression of NF-κB activation. The combination of mollugin with a MEK1/2 inhibitor may be required in order to achieve optimal efficacy in HER2-overexpressing cancers.

These findings suggest that mollugin is a novel modulator of the HER2 pathway in HER2-overexpressing cancer cells with a potential role in the treatment and prevention of human breast and ovarian cancer with HER2 overexpression (Do et al., 2013).

Blocks Neurotoxicity, Anti-inflammatory

Mollugin also has effects as a neuro-protective agent in glutamate-induced neurotoxicity in the mouse hippocampal HT22 cell line and as an anti-inflammatory agent in lipopolysaccharide-induced microglial activation in BV2 cells. Mollugin showed potent neuro-protective effects against glutamate-induced neuro-toxicity and reactive oxygen species generation in mouse hippocampal HT22 cells.

In addition, the anti-inflammatory effects of mollugin were demonstrated by the suppression of pro-inflammatory mediators, including pro-inflammatory enzymes (inducible nitric oxide synthase and cyclooxygenase-2) and cytokines (tumor necrosis factor-α and interleukin-6). Furthermore, mollugin also activated the p38 mitogen-activated protein kinase (MAPK) pathway both in HT22 and BV2 cells. These results suggest that mollugin may be a promising candidate for the treatment of neurodegenerative diseases related to neuroinflammation (Jeong et al., 2011).

References

Do MT, Hwang YP, Kim HG, et al. (2013). Mollugin inhibits proliferation and induces apoptosis by suppressing fatty acid synthase in HER2-overexpressing cancer cells. Journal of Cellular Physiology, 228(5):1087–1097. doi: 10.1002/jcp.24258.


Jeong GS, Lee DS, Kim DC, et al. (2011). Neuroprotective and anti-inflammatory effects of mollugin via up-regulation of heme oxygenase-1 in mouse hippocampal and microglial cells. Eur J Pharmacol, 654(3):226-34. doi: 10.1016/j.ejphar.2010.12.027.


Kim H, Choi HK, Jeong TC, et al. (2013). Selective inhibitory effects of mollugin on CYP1A2 in human liver microsomes. Food Chem Toxicol, 51:33-7. doi: 10.1016/j.fct.2012.09.013.


Tran TP, Kim HG, Choi JH, et al. (2013). Reversal of P-glycoprotein-mediated Multi-drug resistance is induced by mollugin in MCF-7/adriamycin cells. Phytomedicine. doi:10.1016/j.phymed.2013.01.014.

Tanshinone II A & Tanshinone A (See also Cryptotanshinone)

Cancer:
Leukemia, prostate, breast, gastric, colorectal, nasopharyngeal carcinoma

Action: Chemo-sensitizer, cytostatic, cancer stem cells, anti-cancer, autophagic cell death, cell-cycle arrest

Anti-cancer

Tanshinone IIA and cryptotanshinone could induce CYP3A4 activity (Qiu et al., 2103).

Tanshinone II-A (Tan IIA) is the most abundant diterpene quinone isolated from Danshen (Salvia miltiorrhiza), which has been used in treating cardiovascular diseases for more than 2,000 years in China. Interest in its versatile protective effects in cardiovascular, metabolic, neurodegenerative diseases, and cancers has been growing over the last decade.

Tan IIA is a multi-target drug, whose molecular targets include transcription factors, scavenger receptors, ion channels, kinases, pro- and anti-apoptotic proteins, growth factors, inflammatory mediators, microRNA, and others. More recently, enhanced or synergistic effects can be observed when Tan IIA is used in combination therapy with cardio-protective and anti-cancer drugs (Xu & Liu, 2013).

Leukemia

The in vitro anti-proliferation and apoptosis-inducing effects of Tanshinone IIA on leukemia THP-1 cell lines and its mechanisms of action were investigated. MTT assay was used to detect the cell growth-inhibitory rate; cell apoptotic rate and the mitochondrial membrane potential (Deltapsim) were investigated by flow cytometry (FCM); apoptotic morphology was observed by Hoechst 33258 staining and DNA fragmentation analysis.

It was therefore concluded that Tanshinone IIA has significant growth inhibition effects on THP-1 cells by induction of apoptosis, and that Tanshinone IIA-induced apoptosis on THP-1 cells is mainly related to the disruption of Deltapsim and activation of caspase-3 as well as down-regulation of anti-apoptotic protein Bcl-2, survivin and up-regulation of pro-apoptotic protein Bax. The results indicate that Tanshinone IIA may serve as a potential anti-leukemia agent (Liu et al., 2009).

Prostate Cancer

Chiu et al. (2013) explored the mechanisms of cell death induced by Tan-IIA treatment in prostate cancer cells in vitro and in vivo. Results showed that Tan-IIA caused prostate cancer cell death in a dose-dependent manner, and cell-cycle arrest at G0/G1 phase was noted, in LNCaP cells. The G0/G1 phase arrest correlated with increased levels of CDK inhibitors (p16, p21 and p27) and decrease of the checkpoint proteins. Tan-IIA also induced ER stress in prostate cancer cells: activation and nuclear translocation of GADD153/CCAAT/enhancer-binding protein-homologous protein (CHOP) were identified, and increased expression of the downstream molecules GRP78/BiP, inositol-requiring protein-1α and GADD153/CHOP were evidenced. Blockage of GADD153/CHOP expression by siRNA reduced Tan-IIA-induced cell death in LNCaP cells.

Gastric Cancer

Tan IIA can reverse the malignant phenotype of SGC7901 gastric cancer cells, indicating that it may be a promising therapeutic agent.

Tan IIA (1, 5, 10 µg/ml) exerted powerful inhibitory effects on cell proliferation (P < 0.05, and P < 0.01), and this effect was time- and dose-dependent. FCM results showed that Tan IIA induced apoptosis of SGC7901 cells, reduced the number of cells in S phase and increased those in G0/G1 phase. Tan IIA also significantly increased the sensitivity of SGC7901 gastric cancer cells to ADR and Fu. Moreover, wound-healing and transwell assays showed that Tan IIA markedly decreased migratory and invasive abilities of SGC7901 cells (Xu et al., 2013).

Cell-cycle Arrest

MTT and SRB assays were applied to measure the effects of tanshinone A on cell viability. Cell-cycle distribution and apoptosis were assessed via flow cytometry using PI staining and the Annexin V/PI double staining method respectively. Changes to mitochondrial membrane potential was also detected by flow cytometry. The spectrophotometric method was utilized to detect changes of caspase-3 activity. Western blotting assay was used to evaluate the expression of Bcl-2, Bax and c-Myc proteins.

Results indicated that Tan-IIA displayed significant inhibitory effect on the growth of K562 cells in a dose- and time- dependent manner, and displayed only minimal damage to hepatic LO2 cells.

Tan-IIA could arrest K562 cells in the G0/G1 phase and induce apoptosis, decrease mitochondrial transmembrane potential, and the expressions of Bcl-2 and c-Myc proteins, increase the expression of Bax protein and activity of caspase-3. Accordingly, it was presumed that the induction of apoptosis may be through the endogenous pathway. Subsequently, tanshinone A could be a promising candidate in the development of a novel anti-tumor agent (Zhen et al., 2011).

Prostate Cancer, Chemo-sensitizer

Treatment with a combination of Chinese herbs and cytotoxic chemotherapies has shown a higher survival rate in clinical trials.

Tan-IIA displayed synergistic anti-tumor effects on human prostate cancer PC3 cells and LNCaP cells, when combined with cisplatin in vitro. Anti-proliferative effects were detected via MTT assay. Cell-cycle distribution and apoptosis were detected by flow cytometer. Protein expression was detected by Western blotting. The intracellular concentration of cisplatin was detected by high performance liquid chromatography (HPLC).

Results demonstrated that tanshinone II A significantly enhanced the anti-proliferative effects of cisplatin on human prostate cancer PC3 cells and LNCaP cells with an increase in the intracellular concentration of cisplatin. These effects were correlated with cell-cycle arrest at the S phase and induction of cell apoptosis. Apoptosis could potentially be achieved through the death receptor and mitochondrial pathways, decreased expression of Bcl-2.

Collectively, results indicated that the combination of tanshinone II A and cisplatin had a better treatment effect, in vitro, not only on androgen-dependent LNCaP cells but also on androgen-independent PC3 cells (Hou, Xu, Hu, & Xie, 2013).

Autophagic Cell Death, CSCs

Tan IIA significantly increased the expression of microtubule-associated protein light chain 3 (LC3) II as a hallmark of autophagy in Western blotting and immunofluorescence staining. Tan IIA augmented the phosphorylation of adenosine monophosphate-activated protein kinase (AMPK) and attenuated the phosphorylation of mammalian target of rapamycin (mTOR) and p70 S6K in a dose-dependent manner.Tan IIA dramatically activated the extracellular signal regulated kinase (ERK) signaling pathway including Raf, ERK and p90 RSK in a dose-dependent and time-dependent manner. Consistently, ERK inhibitor PD184352 suppressed LC3-II activation induced by Tan IIA, whereas PD184352 and PD98059 did not affect poly (ADP-ribose) polymerase cleavage and sub-G1 accumulation induced by Tan IIA in KBM-5 leukemia cells.

Tan IIA induces autophagic cell death via activation of AMPK and ERK and inhibition of mTOR and p70 S6K in KBM-5 cells as a potent natural compound for leukemia treatment (Yun et al., 2013).

Cancer stem cells (CSCs) are maintained by inflammatory cytokines and signaling pathways. Tanshinone IIA (Tan-IIA) possesses anti-cancer and anti-inflammatory activities. The purpose of this study is to confirm the growth inhibition effect of Tan-IIA on human breast CSCs growth in vitro and in vivo and to explore the possible mechanism of its activity. After Tan-IIA treatment, cell proliferation and mammosphere formation of CSCs were decreased significantly; the expression levels of IL-6, STAT3, phospho-STAT3 (Tyr705), NF-κBp65 in nucleus and cyclin D1 proteins were decreased significantly; the tumor growth and mean tumor weight were reduced significantly.

Tan-IIA has the potential to target and kill CSCs, and can inhibit human breast CSCs growth both in vitro and in vivo through attenuation of IL-6/STAT3/NF-kB signaling pathways (Lin et al., 2013).

Colorectal Cancer

Tan II-A can effectively inhibit tumor growth and angiogenesis of human colorectal cancer via inhibiting the expression level of COX-2 and VEGF. Angiogenesis plays a significant role in colorectal cancer (CRC) and cyclooxygenase-2 (COX-2) appears to be involved with multiple aspects of CRC angiogenesis (Zhou et al., 2012). The results showed that Tan IIA inhibited the proliferation of inflammation-related colon cancer cells HCT116 and HT-29 by decreasing the production of inflammatory cytokines tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6), which are generated by macrophage RAW264.7 cell line.

Treatment with TanshinoneIIA prevented increased PU.1, a transcriptional activator of miR-155, and hence increased miR-155, whereas aspirin could not. These findings support that the interruption of signal conduction between activated macrophages and colon cancer cells could be considered as a new therapeutic strategy and miR-155 could be a potential target for the prevention of inflammation-related cancer (Tu et al., 2012).

Breast Cancer

The proliferation rate of T47D and MDA-MB-231 cells influenced by 1×10-6 mol·L-1 and 1×10-7 mol·L-1 Tanshinone IIA was analyzed by MTT assay. Estrogen receptor antagonist ICI182, 780 was employed as a tool. Level of ERα and ERβ mRNA in T47D cells was quantified by Real-time RT-PCR assay. Expression of ERα and ERβ protein was measured by flow cytometry. The proliferation rates of T47D cells treated with Tanshinone IIA decreased significantly. Such effects could be partly blocked by ICI182, 780.

Meanwhile, the proliferation rates of MDA-MB-231 cells treated with Tanshinone IIA decreased much more dramatically. Real-time RT-PCR and flow cytometry results showed that Tanshinone IIA could induce elevation of ERα and ERβ, especially ERα mRNA, and protein expression level in T47D cells. Tanshinone IIA shows inhibitory effects on proliferation of breast cancer cell lines (Zhao et al., 2010).

The role of cell adhesion molecules in the process of inflammation has been studied extensively, and these molecules are critical components of carcinogenesis and cancer metastasis. This study investigated the effect of tanshinone I on cancer growth, invasion and angiogenesis on human breast cancer cells MDA-MB-231, both in vitro and in vivo. Tanshinone I dose-dependently inhibited ICAM-1 and VCAM-1 expressions in human umbilical vein endothelial cells (HUVECs) that were stimulated with TNF-α for 6 h.

Additionally, reduction of tumor mass volume and decrease of metastasis incidents by tanshinone I were observed in vivo. In conclusion, this study provides a potential mechanism for the anti-cancer effect of tanshinone I on breast cancer cells, suggesting that tanshinone I may serve as an effective drug for the treatment of breast cancer (Nizamutdinova et al., 2008).

Nasopharyngeal Carcinoma

To investigate anti-cancer effect and potential mechanism of tanshinone II(A) (Tan II(A)) on human nasopharyngeal carcinoma cell line CNE cells, the anti-proliferative effect of Tan II(A) on CNE cells was evaluated by morphological examination, cell growth curves, colonial assay and MTT assay. Tan II(A) could inhibit CNE cell proliferation in dose- and time-dependent manner. After treatment with Tan II(A), intracellular Ca2+ concentration of CNE cells was increased, mitochondria membrane potential of the cells was decreased, relative mRNA level of Bad and MT-1A was up-regulated. Tan II(A) had an anti-cancer effect on CNE cells through apoptosis via a calcineurin-dependent pathway and MT-1A down-regulation, and may be the next generation of chemotherapy (Dai et al., 2011).

References

Chiu SC, Huang SY, Chen SP, et al. (2013). Tanshinone IIA inhibits human prostate cancer cells growth by induction of endoplasmic reticulum stress in vitro and in vivo. Prostate Cancer Prostatic Dis. doi: 10.1038/pcan.2013.38.


Dai Z, Huang D, Shi J, Yu L, Wu Q, Xu Q. (2011). Apoptosis inducing effect of tanshinone II(A) on human nasopharyngeal carcinoma CNE cells. Zhongguo Zhong Yao Za Zhi, 36(15):2129-33.


Hou LL, Xu QJ, Hu GQ, Xie SQ. (2013). Synergistic anti-tumor effects of tanshinone II A in combination with cisplatin via apoptosis in the prostate cancer cells. Acta Pharmaceutica Sinica, 48(5), 675-679.


Lin C, Wang L, Wang H, et al. (2013). Tanshinone IIA inhibits breast cancer stem cells growth in vitro and in vivo through attenuation of IL-6/STAT3/NF-kB signaling pathways. J Cell Biochem, 114(9):2061-70. doi: 10.1002/jcb.24553.


Liu JJ, Zhang Y, Lin DJ, Xiao RZ. (2009). Tanshinone IIA inhibits leukemia THP-1 cell growth by induction of apoptosis. Oncol Rep, 21(4):1075-81.


Nizamutdinova IT, Lee GW, Lee JS, et al. (2008). Tanshinone I suppresses growth and invasion of human breast cancer cells, MDA-MB-231, through regulation of adhesion molecules. Carcinogenesis, 29(10):1885-1892. doi:10.1093/carcin/bgn151


Qiu F, Jiang J, Ma Ym, et al. (2013). Opposite Effects of Single-Dose and Multidose Administration of the Ethanol Extract of Danshen on CYP3A in Healthy Volunteers. Evidence-Based Complementary and Alternative Medicine, 2013(2013) http://dx.doi.org/10.1155/2013/730734


Tu J, Xing Y, Guo Y, et al. (2012). TanshinoneIIA ameliorates inflammatory microenvironment of colon cancer cells via repression of microRNA-155. Int Immunopharmacol, 14(4):353-61. doi: 10.1016/j.intimp.2012.08.015.


Xu M, Cao FL, Li NY, et al. (2013). Tanshinone IIA reverses the malignant phenotype of SGC7901 gastric cancer cells. Asian Pac J Cancer Prev, 14(1):173-7.


Xu S, Liu P. (2013). Tanshinone II-A: new perspectives for old remedies. Expert Opin Ther Pat, 23(2):149-53. doi: 10.1517/13543776.2013.743995.


Yun SM, Jung JH, Jeong SJ, et al. (2013). Tanshinone IIA Induces Autophagic Cell Death via Activation of AMPK and ERK and Inhibition of mTOR and p70 S6K in KBM-5 Leukemia Cells. Phytother Res. doi: 10.1002/ptr.5015.


Zhen X, Cen J, Li YM, Yan F, Guan T, Tang, XZ. (2011). Cytotoxic effect and apoptotic mechanism of tanshinone A, a novel tanshinone derivative, on human erythroleukemic K562 cells. European Journal of Pharmacology, 667(1-3), 129-135. doi: 10.1016/j.ejphar.2011.06.004.


Zhao PW, Niu JZ, Wang JF, Hao QX, Yu J, et al. (2010). Research on the inhibitory effect of Tanshinone IIA on breast cancer cell proliferation. Zhong Guo Yao Li Xue Tong Bao, 26(7):903-906.


Zhou LH, Hu Q, Sui H, et al. (2012). Tanshinone II–a inhibits angiogenesis through down regulation of COX-2 in human colorectal cancer. Asian Pac J Cancer Prev, 13(9):4453-8.

Luteolin

Cancer: Colorectal., ovarian, pancreatic

Action: Anti-inflammatory, immunomodulatory, radio-sensitizer, chemo-sensitizer

Luteolin is a flavonoid found in many plants and foods, including Terminalia chebula (Retz.), Prunella vulgaris (L.) and Perilla frutescens [(L.) Britton].

Luteolin is contained in Ocimum sanctum L . or Ocimum tenuiflorum L , commonly known as Holy Basil in English or Tulsi in various Indian languages, which is an important medicinal plant in the various traditional and folk systems of medicine in Southeast Asia. Scientific studies have shown it to possess anti-inflammatory, analgesic, anti-pyretic, anti-diabetic, hepato-protective, hypolipidemic, anti-stress, and immunomodulatory activities. It has been found to prevent chemical-induced skin, liver, oral., and lung cancers and mediates these effects by increasing the anti-oxidant activity, altering the gene expressions, inducing apoptosis, and inhibiting angiogenesis and metastasis.

Colon Cancer

Luteolin inhibited cyclin-dependent kinase (CDK)4 and CDK2 activity, resulting in G1 arrest with a concomitant decrease of phosphorylation of retinoblastoma protein. Activities of CDK4 and CDK2 decreased within 2 hours after luteolin treatment, with a 38% decrease in CDK2 activity (P < 0.05) observed in cells treated with 40 µmol/l luteolin. Luteolin also promoted G2/M arrest at 24 hours post-treatment by down-regulating cyclin B1 expression and inhibiting cell division cycle (CDC)2 activity. Luteolin promoted apoptosis with increased activation of caspases 3, 7, and 9 and enhanced poly(ADP-ribose) polymerase cleavage and decreased expression of p21CIP1/WAF1, survivin, Mcl-1, Bcl-xL, and Mdm-2. Lim et al. (2007) demonstrated that luteolin promotes both cell-cycle arrest and apoptosis in the HT-29 colon cancer cell line, providing insight about the mechanisms underlying its anti-tumorigenic activities.

Radio-protective

The aqueous extract of Perilla frutescens has been shown to protect mice against γ-radiation-induced sickness and mortality and to selectively protect the normal tissues against the tumoricidal effects of radiation. The chemo-preventive and radio-protective properties of Perilla emphasize aspects that warrant future research to establish its activity and utility in cancer prevention and treatment (Baliga et al., 2013).

Anti-inflammatory

Pre-treatment of RAW 264.7 macrophages with luteolin, luteolin-7-glucoside, quercetin, and the isoflavonoid genistein inhibited both the LPS-stimulated TNF-α and interleukin-6 release, whereas eriodictyol and hesperetin only inhibited TNF-α release. From the compounds tested, luteolin and quercetin were the most potent in inhibiting cytokine production with an IC50 of less than 1 and 5 µM for TNF-α release, respectively. Moreover, luteolin inhibited LPS-induced phosphorylation of Akt. Treatment of macrophages with LPS resulted in increased IκB-α phosphorylation and reduced the levels of IκB-α. Pre-treatment of cells with luteolin abolished the effects of LPS on IκB-α.

Xagorari et al. (2001) concluded that luteolin inhibits protein tyrosine phosphorylation, nuclear factor-κB-mediated gene expression and pro-inflammatory cytokine production in murine macrophages.

Anti-inflammatory; Neuroinflammation

Pre-treatment of primary murine microglia and BV-2 microglial cells with luteolin inhibited LPS-stimulated IL-6 production at both the mRNA and protein levels. Whereas luteolin had no effect on the LPS-induced increase in NF-κB DNA binding activity, it markedly reduced AP-1 transcription factor binding activity. Consistent with this finding, luteolin did not inhibit LPS-induced degradation of IκB-α but inhibited JNK phosphorylation.

Luteolin consumption reduced LPS-induced IL-6 in plasma 4 hours after injection. Furthermore, luteolin decreased the induction of IL-6 mRNA by LPS in the hippocampus but not in the cortex or cerebellum. Taken together, these data suggest luteolin inhibits LPS-induced IL-6 production in the brain by inhibiting the JNK signaling pathway and activation of AP-1 in microglia. Thus, luteolin may be useful for mitigating neuroinflammation (Jang et al., 2008).

Immunostimulatory and Anti-inflammatory

Luteolin (Lut) possesses significant anti-inflammatory activity in well-established models of acute and chronic inflammation, such as xylene-induced ear edema in mice (ED50= 107 mg/ kg), carrageenin-induced swellingof the ankle, acetic acid-induced pleurisy and croton oil-induced gaseous pouch granuloma in rats. Lut had a marked inhibitory effect on the inflammatory exudation, but did not affect the number of leucocytes. Its combined immunostimulatory and anti-inflammatory activity, and inhibitory effect upon immediate hypersensitive response, provide the pharmacologic bases for the beneficial effects of Lut in the treatment of chronic bronchitis (Chen et al., 1986).

Anti-inflammatory

Luteolin dose-dependently inhibited the expression and production of those inflammatory genes and mediators in macrophages stimulated with lipopolysaccharide (LPS). Semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) assay further confirmed the suppression of LPS-induced TNF- α, IL-6, iNOS and COX-2 gene expression by luteolin at a transcriptional level. Luteolin also reduced the DNA binding activity of nuclear factor-kappa B (NF-κB) in LPS-activated macrophages.

In addition, luteolin significantly inhibited the LPS-induced DNA binding activity of activating protein-1 (AP-1). It was also found that luteolin attenuated the LPS-mediated protein kinase B (Akt) and IKK phosphorylation, as well as reactive oxygen species (ROS) production. In sum, these data suggest that, by blocking NF-κB and AP-1 activation, luteolin acts to suppress the LPS-elicited inflammatory events in mouse alveolar macrophages, and this effect was mediated, at least in part, by inhibiting the generation of reactive oxygen species. These observations suggest a possible therapeutic application of this agent for treating inflammatory disorders in the lung (Chen et al., 2007).

Pancreatic Cancer; Chemo-enhancing

Simultaneous treatment or pre-treatment (0, 6, 24 and 42h) of flavonoids and chemotherapeutic drugs and various concentrations (0-50µM) were assessed using the MTS cell proliferation assay. Pre-treatment for 24 hours with 13µM of either Apigenin or Luteolin, followed by Gem for 36 h was optimal to inhibit cell proliferation.

Pre-treatment of cells with 11-19µM of either flavonoid for 24 hours resulted in 59%–73% growth inhibition when followed by Gem (10µM, 36 hours). Lut (15µM, 24 hours) pre-treatment followed by Gem (10µM, 36h), significantly decreased protein expression of nuclear GSK-3β and NF-κB p65 and increased pro-apoptotic cytosolic cytochrome c. Pre-treatment of human pancreatic cancer cells BxPC-3 with low concentrations of Lut effectively aid in the anti-proliferative activity of chemotherapeutic drugs (Johnson et al., 2013).

Ovarian Cancer

Recent studies further indicate that luteolin potently inhibits VEGF production and suppresses ovarian cancer cell metastasis in vitro. Lastly, oridonin and wogonin were suggested to suppress ovarian CSCs as is reflected by down-regulation of the surface marker EpCAM.

Unlike NSAIDS (non-steroid anti-inflammatory drugs), well-documented clinical data for phyto-active compounds are lacking. In order to evaluate objectively the potential benefit of these compounds in the treatment of ovarian cancer, strategically designed, large scale studies are warranted (Chen et al., 2012).

Chemo-sensitizer

The sensitization effect of luteolin on cisplatin-induced apoptosis is p53 dependent, as such effect is only found in p53 wild-type cancer cells but not in p53 mutant cancer cells. Moreover, knockdown of p53 by small interfering RNA made p53 wild-type cancer cells resistant to luteolin and cisplatin. The critical role of c-Jun NH(2)-terminal kinase (JNK) was identified in regulation of p53 protein stability: luteolin activates JNK, and JNK then stabilizes p53 via phosphorylation, leading to reduced ubiquitination and proteasomal degradation.

An in vivo nude mice xenograft model confirmed that luteolin enhanced the cancer therapeutic activity of cisplatin via p53 stabilization and accumulation. In summary, data from this study reveal a novel molecular mechanism involved in the anti-cancer effects of luteolin and support its potential clinical application as a chemo-sensitizer in cancer therapy (Shi et al., 2007).

Breast Cancer; Chemo-sensitzer

Luteolin is a flavonoid that has been identified in many plant tissues and exhibits chemo-preventive or chemo-sensitizing properties against human breast cancer. However, the oncogenic molecules in human breast cancer cells that are inhibited by luteolin treatment have not been identified.

Relatively high levels of cyclin E2 (CCNE2) protein expression were detected in tamoxifen-resistant (TAM-R) MCF-7 cells. These results showed that the level of CCNE2 protein expression was specifically inhibited in luteolin-treated (5µM) TAM-R cells, either in the presence or absence of 4-OH-TAM (100nM). Combined treatment with 4-OH-TAM and luteolin synergistically sensitized the TAM-R cells to 4-OH-TAM. The results of this study suggest that luteolin can be used as a chemo-sensitizer to target the expression level of CCNE2 and that it could be a novel strategy to overcome TAM resistance in breast cancer patients (Tu et al., 2013).

References

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Chen MZ, Jin WZ, Dai LM, Xu SY. (1986). Effect of luteolin on inflammation and immune function. Chinese Journal of Pharmacology and Toxicology, 1986-01.

Chen SS, Michael A, Butler-Manuel SA. (2012). Advances in the treatment of ovarian cancer: a potential role of anti-inflammatory phytochemicals. Discov Med, 13(68):7-17.

Jang S, Kelley KW, Johnson RW. (2008). Luteolin reduces IL-6 production in microglia by inhibiting JNK phosphorylation and activation of AP-1. PNAS, 105(21):7534-7539

Johnson JL, Gonzalez de Mejia E. (2013). Interactions between dietary flavonoids apigenin or luteolin and chemotherapeutic drugs to potentiate anti-proliferative effect on human pancreatic cancer cells, in vitro. Food Chem Toxicol, S0278-6915(13)00491-2. doi: 10.1016/j.fct.2013.07.036.

Lim DY, Jeong Y, Tyner Al., Park JHY. (2007). Induction of cell-cycle arrest and apoptosis in HT-29 human colon cancer cells by the dietary compound luteolin. Am J Physiol Gastrointest Liver Physiol, 292: G66-G75. doi:10.1152/ajpgi.00248.2006.

Shi R, Huang Q, Zhu X, et al. (2007). Luteolin sensitizes the anti-cancer effect of cisplatin via c-Jun NH2-terminal kinase-mediated p53 phosphorylation and stabilization. Molecular Cancer Therapeutics, 6(4):1338-1347. doi: 10.1158/1535-7163.MCT-06-0638.

Tu SH, Ho CT, Liu MF, et al. (2013). Luteolin sensitizes drug-resistant human breast cancer cells to tamoxifen via the inhibition of cyclin E2 expression. Food Chem, 141(2):1553-61. doi: 10.1016/j.foodchem.2013.04.077.

Xagorari A, Papapetropoulos A, Mauromatis A, et al. (2001). Luteolin inhibits an endotoxin-stimulated phosphorylation cascade and pro-inflammatory cytokine production in macrophages. JPET, 296(1):181-187.