Category Archives: HIF

A549, Akt, angiogenesis, Anti-angiogenic, Anti-cancer, Anti-estrogenic, anti-inflammatory, anti-lymphangiogenesis, anti-metastasis, Anti-metastatic, anti-tumor, anti-tumor activity, apoptosis, apoptosis-inducing, Apoptotic, BAX, Bcl-2, Breast cancer, c-ErbB2, CAM, CD31, cell-cycle arrest, Cervical cancer, Chapter 7 Isolates and Cancer Research, chemo-preventive, Chemo-preventive agent, Chemo-protective, Chemo-sensitizer, Chemotherapy, Colon Cancer or Colorectal cancer, COX-2, ER, ER-negative, ER-positive, ERK1, G1, GBC-SD, HCT116, HeLa, Hep G2,Hep 3B and SK-Hep1, HIF, HT-29, hypoxia-induced drug resistance, IGF-1, IL-1, iNOS, LM8, Lung cancer, MCF-7, MCP-1, MDR, metastasis, Multi-Drug Resistance, Multi-drug resistance, neuro-protective, Osteosarcoma, p-Akt, p27, p53, PARP, PGE2, PI3K, PI3K/Akt, Pro-apoptotic, pro-oxidative, ROS, Sarcoma, T47D, MDA-MB-231, TNF, TRAIL, VEGF, VEGF, VEGFR

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.

angiogenesis, Anti-angiogenic, Anti-cancer, Anti-cancer effect, anti-inflammatory, anti-proliferative, anti-tumor, apoptosis, Apoptotic, Chapter 7 Isolates and Cancer Research, chemo-prevention, COX-2, COX-2 inhibitor, cytotoxic, Head and neck cancer, HIF, induces apoptosis, MAPK, MDR, metastasis, MMP9, Multi-Drug Resistance, Multi-drug resistance, Oral cancer, p38, p53, Pro-apoptotic, reduction of cardiotoxicity, ROS, Squamous cell carcinoma, TNF

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.

A549, Akt, angiogenesis, Anti-angiogenic, Anti-cancer, anti-inflammatory, Anti-metastatic, anti-tubulin, apoptosis, bFGF, Breast cancer, c-Jun, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, chemo-prevention, Chemotherapy, Colon Cancer or Colorectal cancer, COX-2, Cytostatic, cytotoxic, Dendrobrium loddigesii, ERK1, G1, G2/M, HCT-116, HIF, induces apoptosis, inflammation, iNOS, JNK, Lung cancer, MDA-MB-231, metastasis, Rectal cancer, ROS, Twist, VEGF, VEGF

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.

Akt, Akt/mTOR/P70S6K, AMPK, angiogenesis, Anti-angiogenic, anti-apoptotic, Anti-cancer, Anti-cancer effect, anti-inflammatory, Anti-metastatic, apoptosis, Apoptotic, BAX, Bladder cancer, CD31, Chapter 7 Isolates and Cancer Research, Colon Cancer or Colorectal cancer, ERK, ERK1, FAK, G0/G1, G1, Glioblastoma, HCT-116, HER-2, HIF, IL-6, induces apoptosis, inhibits angiogenesis, JAK1, JAK2, Lung cancer, Magnolia officinalis, metastasis, MMP2, MTOR, Ovarian cancer, p21, p21/Cip1, p38, p53, P70S6K, PC3, PI3K, PI3K/Akt, PI3K/Akt/MTOR, Pro-apoptotic, Prostate cancer, STAT3, VEGF, VEGF

Magnolol

Cancer:
Bladder, breast, colon, prostate, glioblastoma, ovarian, leukemia, lung

Action: Anti-inflammatory, apoptosis, inhibits angiogenesis, anti-metastatic

Magnolol (Mag), an active constituent isolated from the Chinese herb hou po (Magnolia officinalis (Rehder & Wilson)) has long been used to suppress inflammatory processes. It has anti-cancer activity in colon, hepatoma, and leukemia cell lines.

Anti-inflammatory

Magnolol (Mag) suppressed IL-6-induced promoter activity of cyclin D1 and monocyte chemotactic protein (MCP)-1 for which STAT3 activation plays a role. Pre-treatment of ECs with Mag dose-dependently inhibited IL-6-induced Tyr705 and Ser727 phosphorylation in STAT3 without affecting the phosphorylation of JAK1, JAK2, and ERK1/2. Mag pre-treatment of these ECs dose-dependently suppressed IL-6-induced promoter activity of intracellular cell adhesion molecule (ICAM)-1 that contains functional IL-6 response elements (IREs).

In conclusion, our results indicate that Mag inhibits IL-6-induced STAT3 activation and subsequently results in the suppression of downstream target gene expression in ECs. These results provide a therapeutic basis for the development of Mag as an anti-inflammatory agent for vascular disorders including atherosclerosis (Chen et al., 2006).

Bladder Cancer; Inhibits Angiogenesis

In the present study, Chen et al. (2013) demonstrated that magnolol significantly inhibited angiogenesis in vitro and in vivo, evidenced by the attenuation of hypoxia and vascular endothelial growth factor (VEGF)-induced tube formation of human umbilical vascular endothelial cells, vasculature generation in chicken chorioallantoic membrane, and Matrigel plug.

In hypoxic human bladder cancer cells (T24), treatment with magnolol inhibited hypoxia-stimulated H2O2 formation, HIF-1α induction including mRNA, protein expression, and transcriptional activity as well as VEGF secretion. Interestingly, magnolol also acts as a VEGFR2 antagonist, and subsequently attenuates the downstream AKT/mTOR/p70S6K/4E-BP-1 kinase activation both in hypoxic T24 cells and tumor tissues. As expected, administration of magnolol greatly attenuated tumor growth, angiogenesis and the protein expression of HIF-1α, VEGF, CD31, a marker of endothelial cells, and carbonic anhydrase IX, an endogenous marker for hypoxia, in the T24 xenograft mouse model.

Collectively, these findings strongly indicate that the anti-angiogenic activity of magnolol is, at least in part, mediated by suppressing HIF-1α/VEGF-dependent pathways, and suggest that magnolol may be a potential drug for human bladder cancer therapy.

Colon Cancer; Induces Apoptosis

Emerging evidence has suggested that activation of AMP-activated protein kinase (AMPK), a potential cancer therapeutic target, is involved in apoptosis in colon cancer cells. However, the effects of magnolol on human colon cancer through activation of AMPK remain unexplored.

Magnolol displayed several apoptotic features, including propidium iodide labeling, DNA fragmentation, and caspase-3 and poly(ADP-ribose) polymerase cleavages. Park et al. (2012) showed that magnolol induced the phosphorylation of AMPK in dose- and time-dependent manners.

Magnolol down-regulated expression of the anti-apoptotic protein Bcl2, up-regulated expression of pro-apoptotic protein p53 and Bax, and caused the release of mitochondrial cytochrome c. Magnolol-induced p53 and Bcl2 expression was abolished in the presence of compound C. Magnolol inhibited migration and invasion of HCT-116 cells through AMPK activation. These findings demonstrate that AMPK mediates the anti-cancer effects of magnolol through apoptosis in HCT-116 cells.

Ovarian Cancer

Treatment of HER-2 overexpressing ovarian cancer cells with magnolol down-regulated the HER-2 downstream PI3K/Akt signaling pathway, and suppressed the expression of downstream target genes, vascular endothelial growth factor (VEGF), matrix metalloproteinase 2 (MMP2) and cyclin D1. Consistently, magnolol-mediated inhibition of MMP2 activity could be prevented by co-treatment with epidermal growth factor. Migration assays revealed that magnolol treatment markedly reduced the motility of HER-2 overexpressing ovarian cancer cells. These findings suggest that magnolol may act against HER-2 and its downstream PI3K/Akt/mTOR-signaling network, thus resulting in suppression of HER-2mediated transformation and metastatic potential in HER-2 overexpressing ovarian cancers. These results provide a novel mechanism to explain the anti-cancer effect of magnolol (Chuang et al., 2011).

Lung Cancer

Magnolol has been found to inhibit cell growth, increase lactate dehydrogenase release, and modulate cell cycle in human lung carcinoma A549 cells. Magnolol induced the activation of caspase-3 and cleavage of Poly-(ADP)-ribose polymerase, and decreased the expression level of nuclear factor-κB/Rel A in the nucleus. In addition, magnolol inhibited basic fibroblast growth factor-induced proliferation and capillary tube formation of human umbilical vein endothelial cells. These data indicate that magnolol is a potential candidate for the treatment of human lung carcinoma (Seo et al., 2011).

Prostate Cancer; Anti-metastatic

Matrix metalloproteinases (MMPs) are enzymes involved in various steps of metastasis development. The objective of this study was to study the effects of magnolol on cancer invasion and metastasis using PC-3 human prostate carcinoma cells. Magnolol inhibited cell growth in a dose-dependent manner. In an invasion assay conducted in Transwell chambers, magnolol showed 33 and 98% inhibition of cancer cell at 10 microM and 20 microM concentrations, respectively, compared to the control. The protein and mRNA levels of both MMP-2 and MMP-9 were down-regulated by magnolol treatment in a dose-dependent manner.

These results demonstrate the anti-metastatic properties of magnolol in inhibiting the adhesion, invasion, and migration of PC-3 human prostate cancer cells (Hwang et al., 2010).

Glioblastoma Cancer

Magnolol has been found to concentration-dependently (0-40 microM) decrease the cell number in a cultured human glioblastoma cancer cell line (U373) and arrest the cells at the G0/G1 phase of the cell-cycle.

Pre-treatment of U373 with p21/Cip1 specific antisense oligodeoxynucleotide prevented the magnolol-induced increase of p21/Cip1 protein levels and the decrease of DNA synthesis. Magnolol at a concentration of 100 microM induced DNA fragmentation in U373. These findings suggest the potential applications of magnolol in the treatment of human brain cancers (Chen et al. 2011).

Inhibits Angiogenesis

Magnolol inhibited VEGF-induced Ras activation and subsequently suppressed extracellular signal-regulated kinase (ERK), phosphatidylinositol-3-kinase (PI3K)/Akt and p38, but not Src and focal adhesion kinase (FAK). Interestingly, the knockdown of Ras by short interfering RNA produced inhibitory effects that were similar to the effects of magnolol on VEGF-induced angiogenic signaling events, such as ERK and Akt/eNOS activation, and resulted in the inhibition of proliferation, migration, and vessel sprouting in HUVECs.

In combination, these results demonstrate that magnolol is an inhibitor of angiogenesis and suggest that this compound could be a potential candidate in the treatment of angiogenesis-related diseases (Kim et al., 2013).

References

Chen LC, Liu YC, Liang YC, Ho YS, Lee WS. (2009). Magnolol inhibits human glioblastoma cell proliferation through up-regulation of p21/Cip1. J Agric Food Chem, 57(16):7331-7. doi: 10.1021/jf901477g.


Chen MC, Lee CF, Huang WH, Chou TC. (2013). Magnolol suppresses hypoxia-induced angiogenesis via inhibition of HIF-1 α /VEGF signaling pathway in human bladder cancer cells. Biochem Pharmacol, 85(9):1278-87. doi: 10.1016/j.bcp.2013.02.009.


Chen SC, Chang YL, Wang DL, Cheng JJ. (2006). Herbal remedy magnolol suppresses IL-6-induced STAT3 activation and gene expression in endothelial cells. Br J Pharmacol, 148(2): 226–232. doi: 10.1038/sj.bjp.0706647


Chuang TC, Hsu SC, Cheng YT, et al. (2011). Magnolol down-regulates HER2 gene expression, leading to inhibition of HER2-mediated metastatic potential in ovarian cancer cells. Cancer Lett, 311(1):11-9. doi: 10.1016/j.canlet.2011.06.007.


Hwang ES, Park KK. (2010). Magnolol suppresses metastasis via inhibition of invasion, migration, and matrix metalloproteinase-2/-9 activities in PC-3 human prostate carcinoma cells. Biosci Biotechnol Biochem, 74(5):961-7.


Kim KM, Kim NS, Kim J, et al. (2013). Magnolol Suppresses Vascular Endothelial Growth Factor-Induced Angiogenesis by Inhibiting Ras-Dependent Mitogen-Activated Protein Kinase and Phosphatidylinositol 3-Kinase/Akt Signaling Pathways. Nutr Cancer.


Park JB, Lee MS, Cha EY, et al. (2012). Magnolol-induced apoptosis in HCT-116 colon cancer cells is associated with the AMP-activated protein kinase signaling pathway. Biol Pharm Bull, 35(9):1614-20.


Seo JU, Kim MH, Kim HM, Jeong HJ. (2011). Anti-cancer potential of magnolol for lung cancer treatment. Arch Pharm Res, 34(4):625-33. doi: 10.1007/s12272-011-0413-8.

Akt, angiogenesis, Anti-angiogenic, Anti-cancer, anti-inflammatory, Anti-metastatic, Anti-oxidation, anti-proliferative, anti-tumor, anti-tumor activity, apoptosis, apoptosis-inducing, Apoptotic, AR, BAX, Bcl-2, BCR, Bladder cancer, Breast cancer, Breast cancer cell lines, CAM, cancer stem cells, CCNE2, CDC2, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, chemo-enhancing, chemo-preventive, Chemo-protective, Chemo-sensitizer, chemo-sensitzer, Chemoprevention, Chemotherapy, Colon Cancer or Colorectal cancer, COX-2, CSCs, down-regulate COX-2, EGFR, ERK, G2/M, GSTP1, HER2, HIF, HO-1, IL-1, IL-6, IL-8, inflammation, inhibits angiogenesis, Liver cancer, Lymphoma, MAPK, Melanoma, metastasis, MTOR, Multi-Drug Resistance, Multi-drug resistance, Nitric Oxide, NQO1, Osteosarcoma, Ovarian cancer, p38, p65, P70S6K, Pancreatic cancer, PARP, PI3K, Pro-apoptotic, Prostate cancer, Rectal cancer, Rh-123, ROS, Sarcoma, SHH, TAM resistance, TNF, Topo-II, VEGF, VEGF

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.

A549, ABCG2, Akt, angiogenesis, Anti-cancer, anti-tumor, apoptosis, Apoptotic, BCRP, Bladder cancer, Breast cancer, Chapter 7 Isolates and Cancer Research, EJ, HIF, Lung cancer, MCF-7, MDR, MTOR, PC3, Prostate cancer, VEGF, VEGF

Dauricine

Cancer: Prostate, urinary system, breast, lung

Action: MDR

Lung Cancer

Menispermum dauricum DC (Moonseed) contains several alkaloids, of which dauricine can account for as much as 50% of the alkaloids present. In human lung adenocarcinoma A549 cells, these alkaloids activate caspase-3 by activating caspases-8 and -9. Accordingly, these alkaloids induce apoptosis through the apoptosis death receptor and mitochondrial pathways (Wang et al., 2011).

Prostate Cancer

The anti-tumor effects of asiatic moonseed rhizome extraction-dauricine were explored on bladder cancer EJ cell strain, prostate cancer PC-3Mcell strain and primary cell culture system. The main effective component, phenolic alkaloids of Menispermum dauricum, was extracted and separated from asiatic moonseed rhizome by chemical method.

Dauricine had an obvious proliferation inhibition effect on the main tumor cells in urinary system. The minimum drug sensitivity concentration was between 3.81-5.15 µg/mL, and the inhibition ratio increased with the increased concentration. Dauricine, the main effective component extracted from asiatic moonseed rhizome, had good inhibition effect on tumor cells in the urinary system. At the same time, Dauricine has certain inhibition effects on the primary cultured tumor cell (Wang et al., 2012).

Breast Cancer

Serum-starved MCF-7 cells were pretreated for 1 h with different concentrations of dauricine (Dau), followed by incubation with IGF-I for 6 h. Dau significantly inhibited IGF-I-induced HIF-1alpha protein expression but had no effect on HIF-1alpha mRNA expression. However, Dau remarkably suppressed VEGF expression at both protein and mRNA levels in response to IGF-I. Mechanistically, Dau suppressed IGF-I-induced HIF-1alpha and VEGF protein expression mainly by blocking the activation of PI-3K/AKT/mTOR signaling pathway.

Dau inhibits human breast cancer angiogenesis by suppressing HIF-1alpha protein accumulation and VEGF expression, which may provide a novel potential mechanism for the anti-cancer activities of Dau in human breast cancer (Tang et al., 2009).

Breast Cancer; MDR

The potentiation of vincristine-induced apoptosis by tetrandrine, neferine and dauricine isolated from Chinese medicinal plants in the human mammary MCF-7 Multi-drug-resistant cells was investigated. The apoptotic cells induced by vincristine alone accounted for about 10% of all the cancer cells, while the percentage of apoptotic cells induced by a combination of vincristine with tetrandrine, neferine, or dauricine was found to be significantly higher than that by vincristine alone, and their reversal effects were positively correlated with the drug concentration and the exposure time.

In addition, tetrandrine was shown to be the most potent in the reversal efficacy among the three compounds to be tested for apoptosis in vitro. Tetrandrine, neferine and dauricine showed obvious potentiation of vincristine-induced apoptosis in the human mammary MCF-7 multi-drug-resistant cells (Ye et al., 2001).

MDR

Bisbenzylisoquinoline alkaloids are a large family of natural phytochemicals with great potential for clinical use. The interaction between breast cancer resistant protein (BCRP), sometimes called ATP binding cassette protein G2 (ABCG2), and 5 bisbenzylisoquinoline alkaloids (neferine, isoliensinine, liensinine, dauricine and tetrandrine) was evaluated using LLC-PK1/BCRP cell model.

The intracellular accumulation and bi-directional transport studies were conducted, and then molecular docking analysis was carried out employing a homology model of BCRP. This data indicates that BCRP could mediate the excretion of liensinine and dauricine, and thus influence their pharmacological activity and disposition (Tian et al., 2013).

References

Tang XD, Zhou X, Zhou KY. (2009). Dauricine inhibits insulin-like growth factor-I-induced hypoxia inducible factor 1alpha protein accumulation and vascular endothelial growth factor expression in human breast cancer cells. Acta Pharmacol Sin, 30(5):605-16. doi: 10.1038/aps.2009.8.

Tian Y, Qian S, Jiang Y, et al. (2013). The interaction between human breast cancer resistance protein (BCRP) and five bisbenzylisoquinoline alkaloids. Int J Pharm, 453(2):371-9. doi: 10.1016/j.ijpharm.2013.05.053.

Wang J, Li Y, Zu XB, Chen MF, Qi L. (2012). Dauricine can inhibit the activity of proliferation of urinary tract tumor cells. Asian Pac J Trop Med, 5(12):973-6. doi: 10.1016/S1995-7645(12)60185-0.

Wang YG, Sun S, Yang WS, Sun FD, Liu Q. (2011). Extract of Menispermum Dauricum induces apoptosis of human lung cancer cell line A549. J Pract Oncol (Chin), 26:343-346.

Ye ZG, Wang JH, Sun AX, et al. (2001). Potentiation of vincristine-induced apoptosis by tetrandrine, neferine and dauricine in the human mammary MCF-7 Multi-drug-resistant cells. Yao Xue Xue Bao, 36(2):96-9.

AKR1C1/1C2, Akt, anti-inflammatory, anti-oxidant, apoptosis, attenuation of immune suppression, Breast cancer, Chapter 7 Isolates and Cancer Research, chemo-preventive, Chemoprevention, Colon Cancer or Colorectal cancer, Gastric cancer or Stomach cancer, HIF, hNSC, honey, HT-29, Immune, Immunomodulatory, induces apoptosis, Lung cancer, MAPK, MDR, p21, p38, Passiflora caerulea, Passiflora incarnate, Scutellaria baicalensis, SGC7901, VEGF, VEGF

Chrysin

Cancer:
Lung cancer, breast cancer, leukemia, gastric, colon

Action: Anti-inflammatory, induces apoptosis, inhibits HIF-1 α, immunomodulatory

Chrysin (5,7-dihydroxyflavone) is a natural and biologically active compound extracted from many plants (including Scutellaria baicalensis (Georgi), Passiflora caerulea (L.), Passiflora incarnate (L.))., honey, and propolis. It possesses potent anti-inflammatory, anti-oxidant properties, promotes cell death, and perturbs cell-cycle progression. Chrysin induced p38-MAPK activation, and using a specific p38-MAPK inhibitor, SB203580, attenuated chrysin-induced p21 (Waf1/Cip1) expression (Weng et al., 2005).

MDR; NSCLC

Chrysin is a major flavonoid in Scutellaria baicalensis, a widely used traditional Chinese and Japanese medicine. Novel links of pro-inflammatory signals, AKR1C1/1C2 expression and drug resistance in human non-small lung cancer have been demonstrated, and the protein kinase C pathway may play an important role in this process. It is thought that chrysin may act as a potential adjuvant therapy for drug-resistant non-small lung cancer, especially for those with AKR1C1/1C2 overexpression (Wang et al., 2007).

Gastric Cancer, Colon Cancer

Additionally, derivatives of chrysin have been shown to have strong activities against SGC-7901 human gastric cell line and HT-29 human colon cancer cell lines (Zheng et al., 2003).

Breast Cancer

While Chrysin is a potent breast cancer resistance protein inhibitor, it was found to have no significant effect on toptecan pharmacokinetics in rats (Zhang et al., 2005).

VEGF, HIF-1

Chrysin was found to inhibit hypoxia-inducible factor-1α (HIF-1α) expression through AKT signaling. Inhibition of HIF-1α by chrysin resulted in abrogation of vascular endothelial growth factor expression (Fu et al., 2007).

Leukemia

Chrysin has been shown to inhibit proliferation and induce apoptosis, and is more potent than other tested flavonoids in leukemia cells, where chrysin is likely to act via activation of caspases and inactivation of Akt signaling in the cells (Khoo et al., 2010).

Immune

The chemo-preventive action of chrysin has been found to specifically inhibit the enzymatic activity of IDO-1 but not mRNA expression in human neuronal stem cells (hNSC), confirmed by cell-based assay and qRT-PCR. These results suggest that attenuation of immune suppression via inhibition of IDO-1 enzyme activity may be one of the important mechanisms of polyphenols in chemoprevention or combinatorial cancer therapy (Chen et al., 2012).

References

Chen SS, Corteling R, Stevanato L, Sinden J. (2012). Polyphenols Inhibit Indoleamine 3,5-Dioxygenase-1 Enzymatic Activity — A Role of Immunomodulation in Chemoprevention. Discovery Medicine.


Fu B, Xue J, Li Z, et al. (2007). Chrysin inhibits expression of hypoxia-inducible factor-1 α through reducing hypoxia-inducible factor-1 α stability and inhibiting its protein synthesis. Mol Cancer Ther, 6:220. doi: 10.1158/1535-7163.MCT-06-0526


Khoo BY, Chua SL, Balaram P. (2010). Apoptotic Effects of Chrysin in Human Cancer Cell Lines. Int. J. Mol. Sci, 11(5), 2188-2199. doi:10.3390/ijms11052188


Wang HW, Lin CP, Chiu JH, et al. (2007). Reversal of inflammation-associated dihydrodiol dehydrogenases (AKR1C1 and AKR1C2) overexpression and drug resistance in nonsmall cell lung cancer cells by wogonin and chrysin. International Journal of Cancer, 120(9), 2019-2027.


Weng MS, Ho YS, Lin JK. (2005). Chrysin induces G1 phase cell-cycle arrest in C6 glioma cells through inducing p21Waf1/Cip1 expression: involvement of p38 mitogen-activated protein kinase. Biochem Pharmacol, 69(12):1815-27.


Zhang S, Wang X, Sagawa K, Morris ME. (2005). Flavonoids chrysin and benzoflavone, potent breast cancer resistance protein inhibitors, have no significant effect on topotecan pharmacokinetics in rats or mdr1a/1b (,äì/,äì) mice. Drug Metabolism and Disposition, 33(3), 341-348.


Zheng X, Meng WD, Xu YY, Cao JG, & Qing FL. (2003). Synthesis and anti-cancer effect of chrysin derivatives. Bioorganic & Medicinal Chemistry Letters, 13(5), 881-884.

A375 and Hs294, A431, angiogenesis, anti-apoptotic, Anti-cancer, Anti-cancer effect, anti-inflammatory, Anti-metastatic, anti-oxidant, anti-oxidative, anti-proliferative, anti-proliferative effect, apoptosis, apoptosis induction, Apoptotic, Autophagy, BAX, Bcl-2, Bcl-xL, BCRP/ABCG2, Berberis amurensis, BIU-87 and T24, Breast cancer, Breast cancer cell lines, CDK, cell-cycle arrest, Cervical cancer, Chapter 7 Isolates and Cancer Research, chemo-enhancing, chemo-preventive, Chemo-preventive agent, Chemoprevention, Chemotherapy, Colon Cancer or Colorectal cancer, COX-2, cytotoxic, Diarrhea or Constipation, ER, ER-negative, ER-positive, FAK, G0/G1, G1, growth-inhibitory, hepato-protective, HIF, HL-60, inflammation, Leukemia, Liver cancer, LNCaP, DU145, PC-3, Lymphoma, MCF-7, MCF-7, MDA-MB-231, Melanoma, metastasis, Nitric Oxide, OVCAR-3, SKOV-3, PARP, PC3, PGE2, Pro-apoptotic, Prostate cancer, Radio-sensitizer, radiotherapy, ROS, SiHa and CaSki, Skin cancer, T98G, type, u-PA, VEGF, VEGF

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.


Ji JB. (2011). Active Ingredients of Traditional Chinese Medicine: Pharmacology and Application, People's Medical Publishing House Cp., LTD.


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


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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.


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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.


Wu HL, Hsu CY, Liu WH, Yung BYM. (1999). Berberine‐induced apoptosis of human leukemia HL‐60 cells is associated with down‐regulation of nucleophosmin/B23 and telomerase activity. International Journal of Cancer, 81(6):923–929.


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.

AhR, Akt, angiogenesis, Anti-angiogenic, anti-apoptotic, Anti-cancer, Anti-cancer effect, anti-inflammatory, anti-oxidant, anti-proliferative, anti-proliferative effect, anti-tumor, anxiolytic, apoptosis, Apoptotic, BAX, Bcl-2, Breast cancer, CAL-27, FaDu, cardio-protective, cardio-protective against Doxorubicin, cardiovascular disease, Causes cell-cycle arrest, CDK4, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, chemo-preventive, Chemoprevention, Colon Cancer or Colorectal cancer, COX-2, Cytostatic, cytotoxic, G1, G2/M, Head and neck cancer, Hep G2,Hep 3B and SK-Hep1, HIF, HL-60/ADR, IL-6, inflammation, iNOS, JNK, MCF-7, T-47D, MDA-MB-231, Nitric Oxide, Oral cancer, Ovarian cancer, Ovarian cancer cell lines, OVCAR-3, CP-70, IOSE-364, p53, Prostate cancer, ROS, S, VEGF, VEGF, XIAP

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

Akt, anti-apoptotic, Anti-cancer, anti-inflammatory, anti-proliferative, anti-tumor, apoptosis, Apoptotic, Bcl-2, Breast cancer, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Chemotherapy, Colon Cancer or Colorectal cancer, cytotoxic, epidermal growth factor receptor, G2/M, growth-inhibitory, HepG2, HER-2, HER-2/neu, HER2, HIF, HL-60, HL-60/ADR, induces apoptosis, Induces cytotoxicity, inflammation, JAK2, LS1034, Lung cancer, Mahlavu, PLC/PRF/5 and HepG2, Mcl-1, MDA-MB-231, MDR, MDR-1, MDR-1, MTOR, P-gp, p21, p53, Pancreatic cancer, ROS, S, STAT3

Emodin (See also Aloe-Emodin)

Cancer:
Breast, colon, liver, chemotherapy, myeloma, oral., pancreatic, hepatocellular carcinoma, lung, leukemia

Action: MDR-1, cell-cycle arrest

Emodin is an active natural anthraquinone derivative component of a traditional Chinese and Japanese medicine isolated from the root and rhizomes of Rheum palmatum L., Senna obtusifolia [(L.) H.S.Irwin & Barneby], Fallopia japonica [Houtt. (Ronse Decr.)], Kalimeris indica (L.) Sch.Bip., Ventilago madraspatana (Gaertn.), Rumex nepalensis (Spreng.), Fallopia multiflora [(Thunb.) Haraldson], Cassia occidentalis [(L.) Link], Senna siamea [(Lam.) Irwin et Barneby] and Acalypha australis (L.).

Aloe-emodin is an active natural anthraquinone derivative, and is found in the roots and rhizomes of numerous Chinese medicinal herbs (including Rheum palmatum L) and exhibits anti-cancer effects on many types of human cancer cell lines.

Administration of rhubarb (Emodin) can effectively reverse severe acute pancreatitis (SAP) by regulating the levels of IL-15 and IL-18 (Yu & Yang, 2013).

Pancreatic Cancer

Emodin is a tyrosine kinase inhibitor that has an inhibitory effect on mammalian cell-cycle modulation in specific oncogene-overexpressing cells. Recently, there has been great progress in the preclinical study of the anti-cancer mechanisms of emodin. A recent study revealed that emodin has therapeutic effects on pancreatic cancer through various anti-tumor mechanisms. Notably, the therapeutic efficacy of emodin in combination with chemotherapy was found to be higher than the comparable single chemotherapeutic regime, and the combination therapy also exhibited fewer side-effects (Wei et al., 2013).

Hepatocellular Carcinoma, Pancreatic, Breast, Colorectal and Lung Cancers, and Leukemia

Emodin is found as an active ingredient in different Chinese herbs including Rheum palmatum and Polygonam multiflorum, and has diuretic, vasorelaxant, anti-bacterial., anti-viral., anti-ulcerogenic, anti-inflammatory, and anti-cancer effects. The anti-inflammatory effects of emodin have been exhibited in various in vitro as well as in vivo models of inflammation including pancreatitis, arthritis, asthma, atherosclerosis and glomerulonephritis. As an anti-cancer agent, emodin has been shown to suppress the growth of various tumor cell lines including hepatocellular carcinoma, pancreatic, breast, colorectal., leukemia, and lung cancers. Emodin is a pleiotropic molecule capable of interacting with several major molecular targets including NF-κB, casein kinase II, HER2/neu, HIF-1α, AKT/mTOR, STAT3, CXCR4, topoisomerase II, p53, p21, and androgen receptors which are involved in inflammation and cancer (Shrimali et al., 2013).

Hepatocellular Carcinoma

It has been found that emodin induces apoptotic responses in the human hepatocellular carcinoma cell lines (HCC) Mahlavu, PLC/PRF/5 and HepG2. The addition of emodin to these three cell lines led to inhibition of growth in a time-and dose-dependent manner. Emodin generated reactive oxygen species (ROS) in these cells which brought about a reduction of the intracellular mitochondrial transmembrane potential (ΔΨ m), followed by the activation of caspase–9 and caspase–3, leading to DNA fragmentation and apoptosis.

Preincubation of hepatoma cell lines with the hydrogen peroxide-scavenging enzyme, catalase (CAT) and cyclosporin A (CsA), partially inhibited apoptosis. These results demonstrate that enhancement of generation of ROS, DeltaPsim disruption and caspase activation may be involved in the apoptotic pathway induced by emodin (Jing et al., 2002).

Colon Cancer

In in vitro study, emodin induced cell morphological changes, decreased the percentage of viability, induced G2/M phase arrest and increased ROS and Ca(2+) productions as well as loss of mitochondrial membrane potential (ΔΨ(m)) in LS1034 cells. Emodin-triggered apoptosis was also confirmed by DAPI staining and these effects are concentration-dependent.

In in vivo study, emodin effectively suppressed tumor growth in tumor nude mice xenografts bearing LS1034. Overall, the potent in vitro and in vivo anti-tumor activities of emodin suggest that it might be developed for treatment of colon cancer in the future (Ma et al., 2012).

Myeloid Leukemia

It has been shown that emodin significantly induces cytotoxicity in the human myeloma cells through the elimination of myeloid cell leukemia 1 (Mcl-1). Emodin inhibited interleukin-6–induced activation of Janus-activated kinase 2 (JAK2) and phosphorylation of signal transducer and activator of transcription 3 (STAT3), followed by the decreased expression of Mcl-1. Activation of caspase-3 and caspase-9 was triggered by emodin, but the expression of other anti-apoptotic Bcl-2 family members, except Mcl-1, did not change in the presence of emodin. To clarify the importance of Mcl-1 in emodin-induced apoptosis, the Mcl-1 expression vector was introduced into the human myeloma cells by electroporation. Induction of apoptosis by emodin was almost abrogated in Mcl-1–overexpressing myeloma cells as the same level as in parental cells, which were not treated with emodin. Emodin therefore inhibits interleukin-6–induced JAK2/STAT3 pathway selectively and induces apoptosis in myeloma cells via down-regulation of Mcl-1, which is a good target for treating myeloma. Taken together, these results show emodin as a new potent anti-cancer agent for the treatment of multiple myeloma patients (Muto et al., 2007).

Breast Cancer; Block HER-2

The mechanism by which emodin prevents breast cancer is unknown; however the product of the HER-2/neu proto-oncogene, HER2 has been proposed to be involved. The product of the HER-2/neu proto-oncogene, HER2, is the second member of the human epidermal growth factor receptor (HER) family of tyrosine kinase receptors and has been suggested to be a ligand orphan receptor. Amplification of the HER2 gene and overexpression of the HER2 protein induces cell transformation and has been demonstrated in 10% to 40% of human breast cancer. HER2 overexpression has been suggested to associate with tumor aggressiveness, prognosis and responsiveness to hormonal and cytotoxic agents in breast cancer patients. These findings indicate that HER2 is an appropriate target for tumor-specific therapies.

A number of approaches have been investigated: (1) a humanized monoclonal antibody against HER2, rhuMAbHER2 (trastuzumab), which is already approved for clinical use in the treatment of patients with metastatic breast cancer; (2) tyrosine kinase inhibitors, such as emodin, which block HER2 phosphorylation and its intracellullar signaling; (3) active immunotherapy, such as vaccination; and (4) heat shock protein (Hsp) 90-associated signal inhibitors, such as radicicol derivatives, which induce degradation of tyrosine kinase receptors, such as HER2 (Kurebayashi, 2001).

MDR

The effects of emodin on the nucleoside transport and multi-drug resistance in cancer cells has also been investigated. Nucleoside transport inhibition was determined by thymidine incorporation assay. The cytotoxicity to cancer cells was determined by MTT assay. The pump efflux activity and the expression of P glycoprotein were examined by flow cytometric assay. Emodin was active in the inhibition of nucleoside transport, with an IC 50 value of 9 9 µmol·L -1. Emodin markedly enhanced the cytotoxicity of 5 FU, MMC and MTX against human hepatoma BEL 7402 cells and partly reversed the multi-drug resistance in human breast cancer MCF 7/Adr cells.

Emodin inhibited P-gp pump efflux activity and reduced the expression of P gp in MCF 7/Adr cells. These findings provide a biological basis for the application of emodin as a biochemical modulator to potentiate the effects of anti-tumor drugs and reverse the multi-drug resistance in cancer cells (Jiang et al., 2009).

Cell-cycle Arrest

Large quantities of emodin were isolated from the roots of Rheum emodi and a library of novel emodin derivatives 2–15 were prepared to evaluate their anti-proliferative activities against HepG2, MDA-MB-231 and NIH/3T3 cells lines. The derivatives 3 and 12 strongly inhibited the proliferation of HepG2 and MDA-MB-231 cancer cell line with an IC50 of 5.6, 13.03 and 10.44, 5.027, respectively, which is comparable to marketed drug epirubicin (III). The compounds 3 and 12 were also capable of inducing cell-cycle arrest and caspase dependent apoptosis in HepG2 cell lines and exhibit DNA intercalating activity. These emodin derivatives hold promise for developing safer alternatives to the marketed epirubicin (Narender et al., 2013).

Cell-cycle Arrest; MDR1 & AZT

3'-azido-3'-deoxythymidine (AZT) and emodin altered the cell-cycle distribution and led to an accumulation of cells in S phase. Meanwhile, the expression of MDR1 mRNA/p-gp protein was markedly decreased. These results show a synergistic growth-inhibitory effect of AZT and emodin in K562/ADM cells, which is achieved through S phase arrest. MDR1 might ultimately be responsible for these phenomena (Chen et al., 2013).

References

Chen P, Liu Y, Sun Y, et al. (2013). AZT and emodin exhibit synergistic growth-inhibitory effects on K562/ADM cells by inducing S phase cell-cycle arrest and suppressing MDR1 mRNA/p-gp protein expression. Pharm Biol.


Garg AK, Buchholz TA, Aggarwal BB. (2005). Chemo-sensitization and Radiosensitization of Tumors by Plant Polyphenols. Antioxid Redox Signal., 7(11-12):1630-47.


Jiang XF & Zhen YS. (1999). Reversal of Multi-drug resistance by emodin in cancer cells. Acta Pharmaceutica Sinica, 1999-03.


Jing X, Ueki N, Cheng J, Imanishi H, Hada T. (2002). Induction of apoptosis in hepatocellular carcinoma cell lines by emodin. Cancer Science, 93(8):874–882.


Kurebayashi J. (2001). Biological and clinical significance of HER2 overexpression in breast cancer. Breast Cancer, 8(1):45-51


Ma YS, Weng SW, Lin MW, et al. (2012). Anti-tumor effects of emodin on LS1034 human colon cancer cells in vitro and in vivo: Roles of apoptotic cell death and LS1034 tumor xenografts model. Food Chem Toxicol, 50(5): 1271–1278. doi: 10.1016/j.fct.2012.01.033.


Muto A, Hori M, Sasaki Y, et al. (2007). Emodin has a cytotoxic activity against human multiple myeloma as a Janus-activated kinase 2 inhibitor. Mol Cancer Ther. doi: 10.1158/1535-7163.MCT-06-0605.


Narender T, Sukanya P, Sharma K, et al. (2013). Preparation of novel anti-proliferative emodin derivatives and studies on their cell-cycle arrest, caspase dependent apoptosis and DNA binding interaction. Phytomedicine, 20(10):890-896.


Shrimali D, Shanmugam MK, Kumar AP, et al. (2013). Targeted abrogation of diverse signal transduction cascades by emodin for the treatment of inflammatory disorders and cancer. Cancer Lett:S0304-3835(13)00598-3. doi: 10.1016/j.canlet.2013.08.023.


Wei WT, Lin SZ, Liu DL, Wang ZH. (2013). The distinct mechanisms of the anti-tumor activity of emodin in different types of cancer (Review). Oncol Rep. doi: 10.3892/or.2013.2741.


Yu XW, Yang RZ. (2013). Effects of crude rhubarb on serum IL-15 and IL-18 levels in patients with severe acute pancreatitis. An Hui Yi Xue, 34(3): 285-287.