Category Archives: anti-tumor activity

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.

4T1, angiogenesis, Anti-angiogenic, Anti-cancer, anti-inflammatory, Anti-metastatic, anti-tumor, anti-tumor activity, apoptosis, Autophagy, Breast cancer, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Chemotherapy, Colon Cancer or Colorectal cancer, CT-26, cytotoxic, ERK, G1, growth-inhibitory, immunomodulating, Immunosuppressive activity, induces apoptosis, K562, MCF-7, MCF-7/TAM, MDR, MDR-1, MDR-1, Multi-Drug Resistance, Multi-drug resistance, neuro-protective, Oral cancer, P-gp, p21, p27, PR, S, SAS, tamoxifen resistance, TICs, VEGF, VEGF

Tetrandrine

Cancer:
Breast, leukemia, Oral cancer, renal cell carcinoma, colon

Action: Anti-inflammatory, tamoxifen resistance, cell-cycle arrest, anti-metastatic, MDR

Tetrandrine, a bisbenzylisoquinoline alkaloid from the root of Stephania tetrandra (S, Moore), exhibits a broad range of pharmacological activities, including immunomodulating, anti-hepatofibrogenetic, anti-inflammatory, anti-arrhythmic, anti-portal hypertension, anti-cancer and neuro-protective activities (Li, Wang, & Lu, 2001; Ji, 2011). Tetrandrine has anti-inflammatory and anti-fibrogenic actions, which make tetrandrine and related compounds potentially useful in the treatment of lung silicosis, liver cirrhosis, and rheumatoid arthritis (Kwan & Achike, 2002).

Tetrandrine generally presents its anti-cancer effects in micromolar concentrations. Tetrandrine induces different phases of cell-cycle arrest, depends on cancer cell types (Kuo & Lin, 2003; Meng et al., 2004; Ng et al., 2006) and also induces apoptosis in many human cancer cells, including leukemia, bladder, colon, hepatoma, and lung (Lai et al., 1998; Ng et al., 2006; Wu et al., 2010; He et al., 2011).

In vivo experiments have also demonstrated the potential value of tetrandrine against cancer activity. For example, the survival of mice subcutaneously inoculated with CT-26 cells is extended after daily oral gavage of 50 mg/kg or 150  mg/kg of tetrandrine (Wu et al., 2010). Tetrandrine also inhibits the expression of VEGF in glioma cells, has cytotoxic effect on ECV304 human umbilical vein endothelial cells, and suppresses in vivo angiogenesis (Chen et al., 2009). Tetrandrine-treated mice (10  mg/kg/day) have fewer metastases than vehicle-treated mice, and no acute toxicity or obvious changes can be observed in the body weight of both groups (Chang et al., 2004).

Leukemia

Tetrandrine citrate is a novel orally active tetrandrine salt with potent anti-tumor activity against IM-resistant K562 cells and chronic myeloid leukemia. Tetrandrine citrate-induced growth inhibition of leukemia cells may be involved in the depletion of p210Bcr-Abl mRNA and β-catenin protein (Xu et al., 2012).

Comparative in vitro studies show that tetrandrine has significantly greater suppressive effects on adherence, locomotion and 3H-deoxyglucose uptake of neutrophils, as well as the mitogen-induced lymphocyte responses and mixed lymphocyte reactions. By contrast, berbamine demonstrated a significantly greater capacity for inhibition of NK cell cytotoxicity. These results show that tetrandrine is superior to berbamine in most aspects of anti-inflammatory and immunosuppressive activity.

Since these two alkaloids differ by only one substitution in the side chain of one of the benzene rings, these findings may provide further insight into structure-activity relationships and clues to the synthesis and development of active analogues of this promising class of drugs for the treatment of chronic inflammatory diseases (Li et al., 1989).

MDR, Breast Cancer

Tetrandrine also has been found to have extensive pharmacological activity, including positive ion channel blockade and inhibition of multiple drug resistance proteins. These activities are very similar to that of salinomycin, a known drug targeting breast cancer initiation cells (TICs). Tetrandrine has been probed for this activity, targeting of breast cancer TICs. SUM-149, an inflammatory breast cancer cell line, and SUM-159, a non-inflammatory metaplastic breast cancer cell line, were used in these studies.

In summary, tetrandrine demonstrates significant efficacy against in vitro surrogates for inflammatory and aggressive breast cancer TICs (Xu et al., 2011).

Leukemia, MDR

The potential mechanism of the chemotherapy resistance in acute myeloid leukemia (AML) is the multi-drug resistance (MDR-1) gene product P-glycoprotein (P-gp), which is often overexpressed in myeloblasts from acute myeloid leukemia. In a multi-center clinical trial, 38 patients with poor risk forms of AML were treated with tetrandrine (TET), a potent inhibitor of the MDR-1 efflux pump, combined with daunorubicin (DNR), etoposide and cytarabine (TET–DEC). Overall, postchemotherapy marrow hypoplasia was achieved in 36 patients. Sixteen patients (42%) achieved complete remission or restored chronic phase, 9 achieved partial remission (PR) and 13 failed therapy.

These data indicate that TET–DEC was relatively well tolerated in these patients with poor risk AML, and had encouraging anti-leukemic effects (Xu et al., 2006).

Tamoxifen

Tetrandrine (Tet) had a significant reversal of tamoxifen drug resistance breast cancer cells resistant (MCF-7/TAM). The non-cytotoxic dose (0. 625 microg/mL) reversed the resistance by 2.0 folds. MRP1 was reduced at gene (P <0.05) and protein levels when Tet effected on MCF-7ITAM cells. Tet could reverse the drug resistance of MCF-7/TAM cells, and the reverse mechanism may be related to down-regulating MRP1 expression (Chen & Chen, 2013).

Colon Cancer

Tetrandrine (TET) exhibits anti-colon cancer activity. Gao et al. (2013) compared TET with chemotherapy drug doxorubicin in 4T1 tumor-bearing BALB/c mice model and found that TET exhibits anti-cancer metastatic and anti-angiogenic activities better than those of doxorubicin. Local blood perfusion of tumor was markedly decreased by TET after 3 weeks.

Mechanistically, TET treatment leads to a decrease in p-ERK level and an increase in NF- κ B levels in HUVECs. TET also regulated metastatic and angiogenic related proteins, including vascular endothelial growth factor, hypoxia-inducible factor-1 α, integrin β 5, endothelial cell specific molecule-1, and intercellular adhesion molecule-1 in vivo (Chen & Chen, 2013).

Tetrandrine significantly decreased the viability of SAS human oral cancer cells in a concentration- and time-dependent manner. Tet induced nuclear condensation, demonstrated by DAPI staining, and induces apoptosis and autophagy of SAS human cancer cells via caspase-dependent and LC3-I and LC3-II “American Typewriter”; “American Typewriter”;‑dependent pathways (Huang et al., 2013).

Renal Cancer

Tetrandrine treatment showed growth-inhibitory effects on human renal cell carcinoma (RCC) in a time- and dose-dependent manner. Additionally, flow cytometric studies revealed that tetrandrine was capable of inducing G1 cell-cycle arrest and apoptosis in RCC cells. Tet triggered apoptosis and cell-cycle arrest in RCC 786-O, 769-P and ACHN cells in vitro; these events are associated with caspase cascade activation and up-regulation of p21 and p27 (Chen, Ji, & Chen, 2013).

References

Chang KH, Liao HF, Chang HH, et al. (2004). Inhibitory effect of tetrandrine on pulmonary metastases in CT26 colorectal adenocarcinoma-bearing BALB/c mice. American Journal of Chinese Medicine, 32(6):863–872.


Chen HY, Chen XY. (2013). Tetrandrine reversed the resistance of tamoxifen in human breast cancer MCF-7/TAM cells: an experimental research. Zhongguo Zhong Xi Yi Jie He Za Zhi, 33(4):488-91.


Chen T, Ji B, Chen Y. (2013). Tetrandrine triggers apoptosis and cell-cycle arrest in human renal cell carcinoma cells. J Nat Med.


Chen Y, Chen JC, Tseng SH. (2009). Tetrandrine suppresses tumor growth and angiogenesis of gliomas in rats. International Journal of Cancer, 124(10):2260–2269.


Gao JL, Ji X, He TC, et al. (2013). Tetrandrine Suppresses Cancer Angiogenesis and Metastasis in 4T1 Tumor-bearing Mice. Evid Based Complement Alternat Med, 2013:265061. doi: 10.1155/2013/265061.


He BC, Gao JL, Zhang BQ, et al. (2011). Tetrandrine inhibits Wnt/beta-catenin signaling and suppresses tumor growth of human colorectal cancer. Molecular Pharmacology, 79(2):211–219.


Huang AC, Lien JC, Lin MW, et al. (2013). Tetrandrine induces cell death in SAS human oral cancer cells through caspase activation-dependent apoptosis and LC3-I and LC3-II activation-dependent autophagy. Int J Oncol, 43(2):485-94. doi: 10.3892/ijo.2013.1952.


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


Kwan CY, Achike FI. (2002). Tetrandrine and related bis-benzylisoquinoline alkaloids from medicinal herbs: cardiovascular effects and mechanisms of action. Acta Pharmacol Sin, 23(12):1057-68.


Kuo PL and Lin CC. (2003). Tetrandrine-induced cell-cycle arrest and apoptosis in Hep G2 cells. Life Sciences, 73(2):243–252.


Lai YL, Chen YJ, Wu TY, et al. (1998). Induction of apoptosis in human leukemic U937 cells by tetrandrine. Anti-Cancer Drugs, 9(1):77–81.


Li SY, Ling LH, The BS, Seow WK and Thong YH. (1989). Anti-inflammatory and immunosuppressive properties of the bis-benzylisoquinolines: In vitro comparisons of tetrandrine and berbamine. International Journal of Immunopharmacology, 11(4):395-401 doi:10.1016/0192-0561(89)90086-6.


Meng LH, Zhang H, Hayward L, et al. (2004). Tetrandrine induces early G1 arrest in human colon carcinoma cells by down-regulating the activity and inducing the degradation of G 1-S-specific cyclin-dependent kinases and by inducing p53 and p21Cip1. Cancer Research, 64(24):9086–9092.


Ng LT, Chiang LC, Lin YT, and C. C. Lin CC. (2006). Anti-proliferative and apoptotic effects of tetrandrine on different human hepatoma cell lines. American Journal of Chinese Medicine, 34(1):125–135.


Wu JM, Chen Y, Chen JC, Lin TY, Tseng SH. (2010). Tetrandrine induces apoptosis and growth suppression of colon cancer cells in mice. Cancer Letters, 287(2):187–195.


Xu WL, Shen HL, Ao ZF, et al. (2006). Combination of tetrandrine as a potential-reversing agent with daunorubicin, etoposide and cytarabine for the treatment of refractory and relapsed acute myelogenous leukemia. Leukemia Research, 30(4):407-413.


Xu W, Debeb BG, Lacerda L, Li J, Woodward WA. (2011). Tetrandrine, a Compound Common in Chinese Traditional Medicine, Preferentially Kills Breast Cancer Tumor Initiating Cells (TICs) In Vitro. Cancers, 3:2274-2285; doi:10.3390/cancers3022274.


Xu XH, Gan YC, Xu GB, et al. (2012). Tetrandrine citrate eliminates imatinib-resistant chronic myeloid leukemia cells in vitro and in vivo by inhibiting Bcr-Abl/ β-catenin axis. Journal of Zhejiang University SCIENCE B, 13(11):867-874.

Anti-cancer, anti-tumor, anti-tumor activity, apoptosis, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Colon Cancer or Colorectal cancer, G1, Prostate cancer, S, Scutellaria Anti-cancer

Scutellaria (See also apigenin, baicalein, baicalin, chrysin, scutellarein, wogonin, scutellarin, carthamidin, isocarthamidin, wogonin)

Cancer: General anti-cancer, colon, breast, glioma,

Action: Scutellaria Anti-cancer, cell-cycle arrest

Malignant Glioma, Breast Carcinoma and Prostate Cancer

The extracts and individual flavonoids inhibited the proliferation of malignant glioma and breast carcinoma cells without affecting primary or non-malignant cells. The flavonoids exhibited different mechanisms of anti-tumor activity as well as positive interactions. The anti-tumor mechanisms involved induction of apoptosis and cell-cycle arrest at G1/G2. Of the extracts tested, leaf extracts of S. angulosa, S. integrifolia, S. ocmulgee and S. scandens were found to have strong anti-cancer activity (Parajuli et al., 2009).

Anti-Cancer

Scutellaria is a traditional herbal remedy with potential anti-cancer activity. The anti-cancer mechanisms of thirteen Scutellaria species were examined, and their leaf, stem and root extracts analyzed for levels of common biologically active flavonoids: apigenin, baicalein, baicalin, chrysin, scutellarein, and wogonin. Malignant glioma, breast carcinoma and prostate cancer cells were used to determine tumor-specific effects of Scutellaria on cell proliferation, apoptosis and cell-cycle progression, via the MTT assay and flow cytometry-based apoptosis and Cell cycle analysis. The extracts and individual flavonoids inhibited the proliferation of malignant glioma and breast carcinoma cells without affecting primary or non-malignant cells. The flavonoids exhibited different mechanisms of anti-tumor activity as well as positive interactions.

The anti-tumor mechanisms involved induction of apoptosis and cell-cycle arrest at G1/G2. Of the extracts tested, leaf extracts of S. angulosa, S. integrifolia, S. ocmulgee and S. scandens were found to have strong anti-cancer activity. This study provides basis for further mechanistic and translational studies into adjuvant therapy of malignant tumors using Scutellaria leaf tissues (Parajuli et al., 2009).

Colon

Scutellaria barbata (SB) is a medicinal plant that contains flavonone compounds such as scutellarein, scutellarin, carthamidin, isocarthamidin, and wogonin. A functional proteomic approach was used to study the inhibitory effects of a chemically standardized extract from SB in human colon adrencarcinoma, LoVo. Results suggest that the chemically standardized extract from SB can induce cell death in the human colon cancer cell line. Goh, Lee, & Ong (2005) showed that the proposed platform provided a rapid approach to study the molecular mechanism because of the inhibitory effects of different doses of the botanical extracts on LoVo cell lines. This included a network of proteins involved in metabolism, regulation of the cell-cycle, and transcription-factor activity.

References

Goh D, Lee YH, Ong ES. (2005). Inhibitory effects of a chemically standardized extract from Scutellaria barbata in human colon cancer cell lines, LoVo. J Agric Food Chem, 53(21):8197-204.


Parajuli P, Joshee N, Rimando AM, Mittal S, Yadav AK. (2009). In vitro anti-tumor mechanisms of various Scutellaria extracts and constituent flavonoids. Planta Med, 75(1):41-8. doi: 10.1055/s-0028-1088364.

anti-apoptotic, Anti-cancer, anti-inflammatory, anti-oxidant, anti-proliferative, anti-tumor, anti-tumor activity, apoptosis, apoptosis induction, Apoptotic, AR, BAX, Bcl-2, Bladder cancer, Breast cancer, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Colon Cancer or Colorectal cancer, cytotoxic, EJ, T24, 5637, G2/M, growth-inhibitory, HCT-116, L1210, MDA-MB-231, Melanoma, MT-4, Pro-apoptotic, pro-oxidative, Prostate cancer, Rectal cancer, ROS, S, XIAP

Sanguinarine (See also chelerythrine)

Cancer:
Prostate, bladder, breast, colon, melanoma, leukemia

Action: Pro-oxidative, anti-inflammatory, apoptosis induction

AR+/AR- Prostate Cancer

Sanguinarine, a benzophenanthridine alkaloid derived from the bloodroot plant Sanguinaria canadensis (L.), has been shown to possess anti-microbial, anti-inflammatory, anti-cancer and anti-oxidant properties. It has been shown that sanguinarine possesses strong anti-proliferative and pro-apoptotic properties against human epidermoid carcinoma A431 cells and immortalized human HaCaT keratinocytes. Employing androgen-responsive human prostate carcinoma LNCaP cells and androgen-unresponsive human prostate carcinoma DU145 cells, the anti-proliferative properties of sanguinarine against prostate cancer were also examined.

The mechanism of the anti-proliferative effects of sanguinarine against prostate cancer were examined by determining the effect of sanguinarine on critical molecular events known to regulate the cell-cycle and the apoptotic machinery.

A highlight of this study was the fact that sanguinarine induced growth-inhibitory and anti-proliferative effects in human prostate carcinoma cells irrespective of their androgen status. To our knowledge, this is the first study showing the involvement of cyclin kinase inhibitor-cyclin-cyclin-dependent kinase machinery during cell-cycle arrest and apoptosis of prostate cancer cells by sanguinarine. These results suggest that sanguinarine may be developed as an agent for the management of prostate cancer (Adhami et al., 2004).

Breast Cancer

The effects of this compound were examined on reactive oxygen species (ROS) production and its association with apoptotic tumor cell death using a human breast carcinoma MDA-MB-231 cell line. Cytotoxicity was evaluated by trypan blue exclusion methods. Apoptosis was detected using DAPI staining, agarose gel electrophoresis and flow cytometer. The expression levels of proteins were determined by Western blot analyzes and caspase activities were measured using colorimetric assays.

These observations clearly indicate that ROS is involved in the early molecular events in the sanguinarine-induced apoptotic pathway. Data suggests that sanguinarine-induced ROS are key mediators of MMP collapse, which leads to the release of cytochrome c followed by caspase activation, culminating in apoptosis (Choi, Kim, Lee & Choi, 2008).

Leukemia

Sanguinarine, chelerythrine and chelidonine are isoquinoline alkaloids derived from the greater celandine. They possess a broad spectrum of pharmacological activities. It has been shown that their anti-tumor activity is mediated via different mechanisms, which can be promising targets for anti-cancer therapy.

This study focuses on the differential effects of these alkaloids upon cell viability, DNA damage, and nucleus integrity in mouse primary spleen and lymphocytic leukemic cells, L1210. Sanguinarine and chelerythrine produced a dose-dependent increase in DNA damage and cytotoxicity in both primary mouse spleen cells and L1210 cells. Chelidonine did not show a significant cytotoxicity or damage DNA in both cell types, but completely arrested growth of L1210 cells.

Data suggests that cytotoxic and DNA-damaging effects of chelerythrine and sanguinarine are more selective against mouse leukemic cells and primary mouse spleen cells, whereas chelidonine blocks proliferation of L1210 cells. The action of chelidonine on normal and tumor cells requires further investigation (Kaminsky, Lin, Filyak, & Stoika, 2008).

T-lymphoblastic Leukemia

Apoptogenic and DNA-damaging effects of chelidonine (CHE) and sanguinarine (SAN), two structurally related benzophenanthridine alkaloids isolated from Chelidonium majus, were compared. Both alkaloids induced apoptosis in human acute T-lymphoblastic leukemia MT-4 cells. Apoptosis induction by CHE and SAN in these cells were accompanied by caspase-9 and -3 activation and an increase in the pro-apoptotic Bax protein. An elevation in the percentage of MT-4 cells possessing caspase-3 in active form after their treatment with CHE or SAN was in parallel to a corresponding increase in the fraction of apoptotic cells.

The involvement of the mitochondria in apoptosis induction by both alkaloids was supported by cytochrome C elevation in cytosol, with an accompanying decrease in cytochrome C content in the mitochondrial fraction. At the same time, two alkaloids under study differed drastically in their cell-cycle phase-specific effects, since only CHE arrested MT-4 cells at the G2/M phase. It was previously demonstrated, that CHE, in contrast to SAN, does not interact directly with DNA. (Philchenkov, Kaminskyy, Zavelevich, & Stoika, 2008).

Sanguinarine, chelerythrine and chelidonine possess prominent apoptotic effects towards cancer cells. This study found that sanguinarine and chelerythrine induced apoptosis in human CEM T-leukemia cells, accompanied by an early increase in cytosolic cytochrome C that precedes caspases-8, -9 and -3 processing. Effects of sanguinarine and chelerythrine on mitochondria were confirmed by clear changes in morphology (3h), however chelidonine did not affect mitochondrial integrity.

Sanguinarine and chelerythrine also caused marked DNA damage in cells after 1h, but a more significant increase in impaired cells occurred after 6h. Chelidonine induced intensive DNA damage in 15–20% cells after 24h. Results demonstrated that rapid cytochrome C release in CEM T-leukemia cells exposed to sanguinarine or chelerythrine was not accompanied by changes in Bax, Bcl-2 and Bcl-X((L/S)) proteins in the mitochondrial fraction, and preceded activation of the initiator caspase-8 (Kaminskyy, Kulachkovskyy & Stoika, 2008).

Colorectal Cancer

The effects of sanguinarine, a benzophenanthridine alkaloid, was examined on reactive oxygen species (ROS) production, and the association of these effects with apoptotic cell death, in a human colorectal cancer HCT-116 cell line. Sanguinarine generated ROS, followed by a decrease in mitochondrial membrane potential (MMP), activation of caspase-9 and -3, and down-regulation of anti-apoptotic proteins, such as Bcl2, XIAP and cIAP-1. Sanguinarine also promoted the activation of caspase-8 and truncation of Bid (tBid).

Observations clearly indicate that ROS, which are key mediators of Egr-1 activation and MMP collapse, are involved in the early molecular events in the sanguinarine-induced apoptotic pathway acting in HCT-116 cells (Han, Kim, Yoo, & Choi, 2013).

Bladder Cancer

Although the effects of sanguinarine, a benzophenanthridine alkaloid, on the inhibition of some kinds of cancer cell growth have been established, the underlying mechanisms are not completely understood. This study investigated possible mechanisms by which sanguinarine exerts its anti-cancer action in cultured human bladder cancer cell lines (T24, EJ, and 5637). Sanguinarine treatment resulted in concentration-response growth inhibition of the bladder cancer cells by inducing apoptosis.

Taken together, the data provide evidence that sanguinarine is a potent anti-cancer agent, which inhibits the growth of bladder cancer cells and induces their apoptosis through the generation of free radicals (Han et al., 2013).

Melanoma

Sanguinarine is a natural isoquinoline alkaloid derived from the root of Sanguinaria canadensis and from other poppy fumaria species, and is known to have a broad spectrum of pharmacological properties. Current study has found that sanguinarine, at low micromolar concentrations, showed a remarkably rapid killing activity against human melanoma cells. Sanguinarine disrupted the mitochondrial transmembrane potential (ΔΨ m), released cytochrome C and Smac/DIABLO from mitochondria to cytosol, and induced oxidative stress. Thus, pre-treatment with the thiol anti-oxidants NAC and GSH abrogated the killing activity of sanguinarine. Collectively, data suggests that sanguinarine is a very rapid inducer of human melanoma caspase-dependent cell death that is mediated by oxidative stress (Burgeiro, Bento, Gajate, Oliveira, & Mollinedo, 2013).

References

Adhami YM, Aziz MH, Reagan-Shaw SR, et al. (2004). Sanguinarine causes cell-cycle blockade and apoptosis of human prostate carcinoma cells via modulation of cyclin kinase inhibitor-cyclin-cyclin-dependent kinase machinery. Mol Cancer Ther, 3:933


Burgeiro A, Bento AC, Gajate C, Oliveira PJ, Mollinedo F. (2013). Rapid human melanoma cell death induced by sanguinarine through oxidative stress. European Journal of Pharmacology, 705(1-3), 109-18. doi: 10.1016/j.ejphar.2013.02.035.


Choi WY, Kim GY, Lee WH, Choi YH. (2008). Sanguinarine, a benzophenanthridine alkaloid, induces apoptosis in MDA-MB-231 human breast carcinoma cells through a reactive oxygen species-mediated mitochondrial pathway. Chemotherapy, 54(4), 279-87. doi: 10.1159/000149719.


Han MH, Kim GY, Yoo YH, Choi YH. (2013). Sanguinarine induces apoptosis in human colorectal cancer HCT-116 cells through ROS-mediated Egr-1 activation and mitochondrial dysfunction. Toxicology Letters, 220(2), 157-66. doi: 10.1016/j.toxlet.2013.04.020.


Han MH, Park C, Jin CY, et al. (2013). Apoptosis induction of human bladder cancer cells by sanguinarine through reactive oxygen species-mediated up-regulation of early growth response gene-1. PLoS One, 8(5), e63425. doi: 10.1371/journal.pone.0063425.


Kaminskyy V, Lin KW, Filyak Y, Stoika R. (2008). Differential effect of sanguinarine, chelerythrine and chelidonine on DNA damage and cell viability in primary mouse spleen cells and mouse leukemic cells. Cell Biology International, 32(2), 271-277.


Kaminskyy V, Kulachkovskyy O, Stoika R. (2008) A decisive role of mitochondria in defining rate and intensity of apoptosis induction by different alkaloids. Toxicology Letters, 177(3), 168-81. doi: 10.1016/j.toxlet.2008.01.009.


Philchenkov A, Kaminskyy V, Zavelevich M, Stoika R. (2008). Apoptogenic activity of two benzophenanthridine alkaloids from Chelidonium majus L. does not correlate with their DNA-damaging effects. Toxicology In Vitro, 22(2), 287-95.

Akt, AMPK, angiogenesis, Anti-angiogenesis, Anti-angiogenic, anti-apoptotic, Anti-cancer, anti-metastasis, Anti-metastatic, anti-tumor, anti-tumor activity, apoptosis, Apoptotic, BAX, Bcl-2, Chapter 7 Isolates and Cancer Research, Chemotherapy, Colon Cancer or Colorectal cancer, enhanced paclitaxel absorption, Glioblastoma, HO-1, HT-29, Lymphoma, MAPK, MDR, metastasis, P-gp, p21, p38, p53, PARP, Pro-apoptotic, Prostate cancer, ROS, S, VEGF, VEGF

RG3 (See also Ginsenosides)

Cancer: Glioblastoma, prostate, breast, colon

Action: Anti-angiogenesis, MDR, enhances chemotherapy, MDR, enhanced paclitaxel absorption, anti-metastatic

RG3 is a ginsenoside isolated from red ginseng (Panax ginseng (L.)), after being peeled, heated, and dried.

Angiosuppressive Activity

Aberrant angiogenesis is an essential step for the progression of solid tumors. Thus anti-angiogenic therapy is one of the most promising approaches to control tumor growth.

Rg3 was found to inhibit the proliferation of human umbilical vein endothelial cells (HUVEC) with an IC50 of 10 nM in Trypan blue exclusion assay.

Rg3 (1-10(3) nM) also dose-dependently suppressed the capillary tube formation of HUVEC on the Matrigel in the presence or absence of 20 ng/ml vascular endothelial growth factor (VEGF). The Matrix metalloproteinases (MMPs), such as MMP-2 and MMP-9, which play an important role in the degradation of basement membrane in angiogenesis and tumor metastasis present in the culture supernatant of Rg3-treated aortic ring culture were found to decrease in their gelatinolytic activities. Taken together, these data underpin the anti-tumor properties of Rg3 through its angiosuppressive activity (Yue et al., 2006).

Glioblastoma

Rg3 has been reported to exert anti-cancer activities through inhibition of angiogenesis and cell proliferation. The mechanisms of apoptosis by ginsenoside Rg3 were related with the MEK signaling pathway and reactive oxygen species. Our data suggest that ginsenoside Rg3 is a novel agent for the chemotherapy of glioblastoma multiforme (GBM) (Choi et al., 2013).

Sin, Kim, & Kim (2012) report that chronic treatment with Rg3 in a sub-lethal concentration induced senescence-like growth arrest in human glioma cells. Rg3-induced senescence was partially rescued when the p53/p21 pathway was inactivated. Data indicate that Rg3 induces senescence-like growth arrest in human glioma cancer through the Akt and p53/p21-dependent signaling pathways.

MDR/Enhanced Paclitaxel Absorption

The penetration of paclitaxel through the Caco-2 monolayer from the apical side to the basal side was facilitated by 20(s)-ginsenoside Rg3 in a concentration-dependent manner. Rg3 also inhibited P-glycoprotein (P-gp), and the maximum inhibition was achieved at 80 µM (p < 0.05). The relative bioavailability (RB)% of paclitaxel with 20(s)-ginsenoside Rg3 was 3.4-fold (10 mg/kg) higher than that of the control. Paclitaxel (20 mg/kg) co-administered with 20(s)-ginsenoside Rg3 (10 mg/kg) exhibited an effective anti-tumor activity with the relative tumor growth rate (T/C) values of 39.36% (p <0.05).

The results showed that 20(s)-ginsenoside Rg3 enhanced the oral bioavailability of paclitaxel in rats and improved the anti-tumor activity in nude mice, indicating that oral co-administration of paclitaxel with 20(s)-ginsenoside Rg3 could provide an effective strategy in addition to the established i.v. route (Yang et al., 2012).

Prostate Cancer

The anti-proliferation effect of Rg3 on prostate cancer cells has been well reported. Rg3 treatment triggered the activation of p38 MAPK; and SB202190, a specific inhibitor of p38 MAPK, antagonized the Rg3-induced regulation of AQP1 and cell migration, suggesting a crucial role for p38 in the regulation process. Rg3 effectively suppresses migration of PC-3M cells by down-regulating AQP1 expression through p38 MAPK pathway and some transcription factors acting on the AQP1 promoter (Pan et al., 2012).

Enhances Chemotherapy

The clinical use of cisplatin (cis-diamminedichloroplatinum II) has been limited by the frequent emergence of cisplatin-resistant cell populations and numerous other adverse effects. Therefore, new agents are required to improve the therapy and health of cancer patients. Oral administration of ginsenoside Rg3 significantly inhibited tumor growth and promoted the anti-neoplastic efficacy of cisplatin in mice inoculated with CT-26 colon cancer cells. In addition, Rg3 administration remarkably inhibited cisplatin-induced nephrotoxicity, hepatotoxicity and oxidative stress.

Rg3 promotes the efficacy of cisplatin by inhibiting HO-1 and NQO-1 expression in cancer cells and protects the kidney and liver against tissue damage by preventing cisplatin-induced intracellular ROS generation (Lee et al., 2012).

Colon Cancer

Rg3-induced apoptosis in HT-29 cells is mediated via the AMPK signaling pathway, and that 20(S)-Rg3 is capable of inducing apoptosis in colon cancer. Rg3-treated cells displayed several apoptotic features, including DNA fragmentation, proteolytic cleavage of poly (ADP-ribose) polymerase (PARP) and morphological changes. 20(S)-Rg3 down-regulated the expression of anti-apoptotic protein B-cell CLL/lymphoma 2 (Bcl2), up-regulated the expression of pro-apoptotic protein of p53 and Bcl-2-associated X protein (Bax), and caused the release of mitochondrial cytochrome c, PARP, caspase-9 and caspase-3 (Yuan et al., 2010).

Anti-metastatic

Studies have linked Rg3 with anti-metastasis of cancer in vivo and in vitro and the CXC receptor 4 (CXCR4) is a vital molecule in migration and homing of cancer to the docking regions. At a dosage without obvious cytotoxicity, Rg3 treatment elicits a weak CXCR4 stain color, decreases the number of migrated cells in CXCL12-elicited chemotaxis and reduces the width of the scar in wound healing and Rg3 is a new CXCR4 inhibitor (Chen et al., 2011).

References

Chen XP, Qian LL, Jiang H, Chen JH. (2011). Ginsenoside Rg3 inhibits CXCR4 expression and related migrations in a breast cancer cell line. Int J Clin Oncol, 16(5):519-23. doi: 10.1007/s10147-011-0222-6.


Choi YJ, Lee HJ, Kang DW, et al. (2013). Ginsenoside Rg3 induces apoptosis in the U87MG human glioblastoma cell line through the MEK signaling pathway and reactive oxygen species. Oncol Rep. doi: 10.3892/or.2013.2555.


Lee CK, Park KK, Chung AS, Chung WY. (2012). Ginsenoside Rg3 enhances the chemosensitivity of tumors to cisplatin by reducing the basal level of nuclear factor erythroid 2-related factor 2-mediated heme oxygenase-1/NAD(P)H quinone oxidoreductase-1 and prevents normal tissue damage by scavenging cisplatin-induced intracellular reactive oxygen species. Food Chem Toxicol, 50(7):2565-74. doi: 10.1016/j.fct.2012.01.005.


Pan XY, Guo H, Han J, et al. (2012). Ginsenoside Rg3 attenuates cell migration via inhibition of aquaporin 1 expression in PC-3M prostate cancer cells. Eur J Pharmacol, 683(1-3):27-34. doi: 10.1016/j.ejphar.2012.02.040.


Sin S, Kim SY, Kim SS. (2012). Chronic treatment with ginsenoside Rg3 induces Akt-dependent senescence in human glioma cells. Int J Oncol., 41(5):1669-74. doi: 10.3892/ijo.2012.1604.


Yang LQ, Wang B, Gan H, et al. (2012). Enhanced oral bioavailability and anti-tumor effect of paclitaxel by 20(s)-ginsenoside Rg3 in vivo. Biopharm Drug Dispos., 33(8):425-36. doi: 10.1002/bdd.1806.


Yuan HD, Quan HY, Zhang Y, et al. (2010). 20(S)-Ginsenoside Rg3-induced apoptosis in HT-29 colon cancer cells is associated with AMPK signaling pathway. Mol Med Rep., 3(5):825-31. doi: 10.3892/mmr.2010.328.


Yue PY, Wong DY, Wu PK, et al. (2006). The angiosuppressive effects of 20 (R)-ginsenoside Rg3. Biochem Pharmacol, 72(4):437-45.

anti-tumor, anti-tumor activity, apoptosis, Breast cancer, Chapter 7 Isolates and Cancer Research, ER, ER-positive, Estrogen modulator

Psoralen and Bakuchiol

Cancer: Breast

Action: Estrogen modulator

The seed of Psoralea corylifolia L. (PCL), a well-known traditional Chinese medicine, has been applied as a tonic or an aphrodisiac agent and commonly used as a remedy for bone fracture, osteomalacia and osteoporosis in China (Lim et al., 2009).

Estrogen Modulator

The estrogen receptor subtype-selective activities of the extracts and compounds derived from PCL were analyzed using the HeLa cell assay. The different fractions, including petroleum ether, CH(2)Cl(2) and EtOAc fractions of the EtOH extract of PCL, showed significant activity in activating either ERalpha or ERbeta, whereas the n-BuOH fraction showed no estrogenic activity. Further chromatographic purification of the active fractions yielded seven compounds including the two coumarins isopsoralen and psoralen, the four flavonoids isobavachalcone, bavachin, corylifol A and neobavaisoflavone, and the meroterpene phenol, bakuchiol. In reporter gene assay, the two coumarins (10(-8)-10(-5)M) acted as ERalpha-selective agonists while the other compounds (10(-9)-10(-6)M) activated both ERalpha and ERbeta.

The estrogenic activities of all compounds could be completely suppressed by the pure estrogen antagonist, ICI 182,780, suggesting that the compounds exert their activities through ER. Only psoralen and isopsoralen as ERalpha agonists promoted MCF-7 cell proliferation significantly. Although all the compounds have estrogenic activity, they may exert different biological effects. These data suggest that both ER subtype-selective and non-selective activities in compounds derived from PCL indicated that PCL could be a new source for selective estrogen-receptor modulators (Xin et al., 2010).

Breast Cancer

The in vitro anti-tumor activity of bakuchiol was examined, compared with tamoxifen. The result of biological activities showed that bakuchiol could inhibit human breast cancer and the IC50 values were 2.89 x 10(-5) mol L(-1) and 8.29 x 10(-3) mol L(-1) against the cells line T-47D and MDA-MB-231 respectively (Chen et al., 2010).

In vitro inhibitory effects of various concentrations of psoralen (25, 12. 5, 6. 25 and 3. 125 µg/mL respectively) on MCF-7 cells with estrogen-receptor (ER) positive and on MDA-MB-231 cells with ER negative were carried out. Psoralen had no inhibitory effect on the growth of MDA-MB-231 cells, but cell apoptosis was increased at early stage. There were 1,053 genes with differential expression in MCF-7 cells assessed by cDNA chips. Of the expression of 1,053 genes, the expression of 657 genes was down-regulated and that of 456 gene was up-regulated.

Psoralen has certain inhibitory effect on the proliferation of ER-positive MCF-7 cells, and its inhibitory mechanism on the growth of breast cancer is probably related to the arrest of the cell at G2 phase by the drug (Tan et al., 2009).

References

Chen HL, Feng HJ, Li YC. (2010). Vitro anti-tumor activity and synthesis of the key intermediate of bakuchiol. Yao Xue Xue Bao, 45(4):467-70.


Lim SH, Ha TY, Kim SR, et al. (2009). Ethanol extract of Psoralea corylifolia L. and its main constituent, bakuchiol, reduce bone loss in ovariectomised Sprague-Dawley rats. Br J Nutr., 101(7):1031-1039


Tan M, Sun J, Zhao H, et al. (2009). Comparative Study on the Anti-tumor Effects of Psoralen on Human Breast Cancer Cell Line MCF-7 and MDA-MB-231 in Vitro. Guang Zhou Zhong Yi Yao Da Xue Xue Bao, 26(4): 359-362.


Xin D, Wang H, Yang J, et al. (2010). Phytoestrogens from Psoralea corylifolia reveal estrogen receptor-subtype selectivity. Phytomedicine, 17(2):126-31. doi: 10.1016/j.phymed.2009.05.015.

A549, LL/2, Akt, angiogenesis, Anti-cancer, anti-tumor, anti-tumor activity, apoptosis, apoptosis-inducing, Apoptotic, BAX, Bcl-2, c-Myc, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Cortex periplocae, Cytostatic, cytostatic effect, cytotoxic, ERK, G0/G1, G1, HeLa, K562, Lung cancer, MCF-7, PC3, Pro-apoptotic, QG-56, SMMC-7721, SW480, T24, TE-13, Eca-109, TRAIL, U937

Periplocin

Cancer: Lung, colorectal, leukemia

Action: Apoptosis-inducing, cytostatic effect

Apoptosis

The anti-tumor component of Cortex periplocae is periplocin. Periplocin is one of the cardenolides isolated from cortex periplocae which is used for treatment of rheumatoid arthritis and reinforcement of bones and tendons in traditional medicine.

Periplocin has been reported to inhibit many cell lines, including MCF-7, TE-13, QG-56, SMMC-7721, T24, Hela, K562, TE-13 and Eca-109 cells. Studies have shown that periplocin reduces the expression of survivin, an inhibitor of apoptosis. It also releases caspases-3 and -7 from complexes and thereby increases their activities, ultimately inducing tumor cell apoptosis (Zhao et al., 2009).

Lung Cancer

The anti-tumor activity of periplocin was investigated in lung cancer cells both in vitro and in vivo, and its anti-cancer mechanism was explored. Periplocin inhibited the growth of lung cancer cells and induced their apoptosis in a time- and dose-dependent manner by cell-cycle arrest in G0/G1 phase. Periplocin exhibited anti-tumor activity both in human (A549) and mouse (LL/2) lung cancer xenograft models. Immunohistochemical analysis revealed that intratumoral angiogenesis was significantly suppressed.

Furthermore, anti-cancer activity mediated by periplocin was associated with decreased level of phosphorylated AKT and ERK both in vitro and in vivo, which are important for cell growth and survival. Moreover, periplocin induced apoptosis by down-regulating Bcl-2 and up-regulating Bax, leading to activation of caspase-3 and caspase-9.

These findings suggest that periplocin could inhibit the growth of lung cancer both in vitro and in vivo, which could be attributed to the inhibition of proliferation and the induction of apoptosis signaling pathways, such as AKT and ERK. These observations provide further evidence on the anti-tumor effect of periplocin, and it may be of importance to further explore its potential role as a therapeutic agent for cancer (Lu et al., 2010).

Colorectal Carcinomas

The Wnt/beta-catenin signaling pathway plays an important role in the development and progression of human cancers, especially in colorectal carcinomas. Periplocin extracted from cortex periplocae (CPP) significantly inhibited the proliferation of SW480 cells in a time-and dose-dependent manner (P<0.01). CPP (0.5 microg/mL) also caused G0/G1 cell-cycle arrest of SW480 cells and induced cell apoptosis (P<0.05). Compared to untreated control cells, after the treatment with CPP, the protein levels of beta-catenin in total cell lysates, cytosolic extracts, and nuclear extracts were reduced (P<0.01); the binding activity of the TCF complex in nucleus to its specific DNA binding site was suppressed; mRNAs of the downstream target genes survivin, c-myc and cyclin D1 were decreased (P<0.01) while beta-catenin mRNA remained unchanged.

CPP could significantly inhibit the proliferation of SW480 cells, which may be through down-regulating the Wnt/beta-catenin signaling pathway (Du et al., 2009).

Pro-apoptotic and Cytostatic Effect/Leukemia

Cardenoliddes are steroid glycosides which are known to exert cardiotonic effects by inhibiting the Na(+)/K(+)-ATPase. Several of these compounds have been shown also to possess anti-tumor potential. The aim of the present work was the characterization of the tumor cell growth inhibition activity of four cardenolides, isolated from Periploca graeca L., and the mechanisms underlying such an effect.

The pro-apoptotic and cytostatic effect of the compounds was tested in U937 (monocytic leukemia) and PC3 (prostate adenocarcinoma). Characterization of apoptosis and cell-cycle impairment was obtained by cytofluorimetry and WB. Periplocymarin and periplocin were the most active compounds, periplocymarin being more effective than the reference compound ouabain. The reduction of cell number by these two cardenolides was due in PC3 cells mainly to the activation of caspase-dependent apoptotic pathways, while in U937 cells to the induction of cell-cycle impairment without extensive cell death. Interestingly, periplocymarin, at cytostatic but non-cytotoxic doses, was shown to sensitize U937 cells to TRAIL. Taken together, these data outline that cardiac glycosides are promising anti-cancer drugs and contribute to the identification of new natural cardiac glycosides to obtain chemically modified non-cardioactive/low toxic derivatives with enhanced anti-cancer potency (Bloise et al., 2009).

References

Bloise E, Braca A, De Tommasi N, Belisario MA. (2009). Pro-apoptotic and cytostatic activity of naturally occurring cardenolides. Cancer Chemother Pharmacol, 64(4):793-802. doi: 10.1007/s00280-009-0929-5.


Du YY, Liu X, Shan BE. (2009). Periplocin extracted from cortex periplocae induces apoptosis of SW480 cells through inhibiting the Wnt/beta-catenin signaling pathway. Ai Zheng, 28(5):456-60.


Lu ZJ, Zhou Y, Song Q, et al. (2010). Periplocin inhibits growth of lung cancer in vitro and in vivo by blocking AKT/ERK signaling pathways. Cell Physiol Biochem, 26(4-5):609-18. doi: 10.1159/000322328.


Zhao LM, Ai J, Zhang Q, et al. (2009). Periplocin (a sort of ethanol from Cortex periplocae) induces apoptosis of esophageal carcinoma cells by influencing expression of related genes. Tumor (Chin), 29:1025-1030.

A549, anti-tumor, anti-tumor activity, apoptosis, Apoptotic, BAX, Bcl-2, Breast cancer, CDC2, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, COX-2, G2/M, induces apoptosis, Lung cancer, MCF-7, p21, p53, Panc-28, Pancreatic cancer, PC3, Pro-apoptotic, pro-apoptotic with 5-FU, Prostate cancer, Radio-sensitizer, radio-sensitizing, ROS

Oleanolic Acid (OA)

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

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

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

Pancreatic Cancer

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

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

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

Radio-sensitizer

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

Prostate Cancer, Lung Cancer, Gastric Cancer, Breast Cancer

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

Hepatocellular Carcinoma

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

References

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


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


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


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


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


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

anti-tumor, anti-tumor activity, apoptosis, Chapter 7 Isolates and Cancer Research, cytotoxic, Melanoma, PC3, PC3 and DU145, Prostate cancer, Prostate cancer cell lines, Radio-sensitizer, radio-sensitizing, U251

Oleandrin

Cancer: Prostate, glioma, melanoma

Action: Radio-sensitizer

Anvirzel is an extract of Nerium oleander (L.) currently undergoing, as Anvirzelª Phase I clinical evaluation as a potential treatment for cancer. Two of the active components of Anvirzel are the cardiac glycosides, oleandrin and oleandrigenin.

Prostate Cancer

In continuing research on the anti-tumor activity of this novel plant extract, the relative abilities of oleandrin and oleandrigenin to inhibit FGF-2 export from two human prostate cancer cell lines, DU145 and PC3, were examined. An ELISA assay was utilized to determine the FGF-2 concentration in the cell culture medium before and after exposure to cardiac glycosides or the parent extract material Anvirzel.

Studies also were conducted with Anvirzel (a hot water extract of Nerium oleander, known as Anvirzelª) and ouabain (found in the ripe seeds of African plants Strophanthus gratus). Oleandrin (0.1 ng/mL) produced a 45.7% inhibition of FGF-2 release from PC3 cells and a 49.9% inhibition from DU145 cells. Non-cytotoxic concentrations (100 ng/mL) of Anvirzel produced a 51.9% and 30.8% inhibition of FGF-2 release, respectively, in the two cell lines. These results demonstrate that Anvirzel, like oleandrin, inhibited FGF-2 export in vitro from PC3 and DU145 prostate cancer cells in a concentration- and time-dependent fashion and may, therefore, contribute to the anti-tumor activity of this novel treatment for cancer (Smith et al., 2001).

Radio-sensitizers; Prostate Cancer

In the present study Nasu et al. (2002) explored the relative radio-sensitization potential of oleandrin, a cardiac glycoside contained within the plant extract known as Anvirzelª. The data show that oleandrin produces an enhancement of sensitivity of PC-3 human prostate cells to radiation; at a cell survival of 0.1, the enhancement factor was 1.32. The magnitude of radio-sensitization depended on duration of exposure of cells to drug prior to radiation treatment.

While a radio-sensitizing effect of oleandrin was evident with only 1 hour of cell exposure to drug, the effect greatly increased with 24 hours of oleandrin pre-treatment.

Activation was greatest when cells were exposed simultaneously to oleandrin and radiation. Inhibition of caspase-3 activation with Z-DEVD-FMK abrogated the oleandrin-induced enhancement of radiation response suggesting that both oleandrin and radiation share a caspase-3 dependent mechanism of apoptosis in the PC-3 cell line.

Glioma, Melanoma

Twelve human tumor cell lines were chosen to examine determinants of human tumor cell sensitivity to cardiac glycosides. In vitro cell culture models of human glioma HF U251 and U251 cells as well as human parental and modified melanoma BRO cells were also included in these studies. Cardiac glycosides such as oleandrin, ouabain and bufalin increased expression of Na+, K+ -ATPase alpha 1 and therefore total Na+, K+ -ATPase activity, which is associated with increased cellular levels of glutathione. Additionally, an increased colony-forming ability was noted in cells with high levels of Na+, K+ -ATPase alpha 1 expression, suggesting that Na+, K+ -ATPase alpha 1 isoform may be actively involved in tumor growth and cell survival (Lin, Ho, & Newman, 2010)

References

Lin Y, Ho DH, Newman RA. (2010). Human tumor cell sensitivity to oleandrin is dependent on relative expression of Na+, K+ -ATPase subunitst. J Exp Ther Oncol, 8(4):271-86.


Nasu S, Milas L, Kawabe S, Raju U, Newman R. (2002). Enhancement of radiotherapy by oleandrin is a caspase-3 dependent process. Cancer Letters, 185(2):145–151. doi:10.1016/S0304-3835(02)00263-X


Smith JA, Madden T, Vijjeswarapu M, Newman RA. (2001). Inhibition of export of fibroblast growth factor-2 (FGF-2) from the prostate cancer cell lines PC3 and DU145 by anvirzel and its cardiac glycoside component, oleandrin. Biochemical Pharmacology, 62(4):469-472. doi:10.1016/S0006-2952(01)00690-6.

Anti-angiogenic, anti-tumor, anti-tumor activity, apoptosis, BAX, Breast cancer, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, chemo-prevention, Cytostatic, ER, G0/G1, G1, growth-inhibitory, Melanoma, Osteosarcoma, p21, p38, PARP, Sarcoma

Nelumbo Extract (NLE):Neferine

Cancer: Liver, osteosarcoma, breast, melanoma

Action: Anti-angiogenic, cytostatic

Neferine is a major bis-benzylisoquinoline alkaloid derived from the green seed embryos of the Indian lotus (Nelumbo nucifera (Gaertn.)).

Identification of natural products that have anti-tumor activity is invaluable to the chemo-prevention and therapy of cancer. The embryos of lotus (Nelumbo nucifera) seeds are consumed in beverage in some parts of the world for their presumed health-benefiting effects. Neferine is a major alkaloid component in lotus embryos.

Hepatitis

Experimental results suggest that neferine exhibited cytotoxicity against HCC Hep3B cells, but not against HCC Sk-Hep1 and THLE-3, a normal human liver cell line. Results demonstrated neferine induced ER stress and apoptosis, acting through multiple signaling cascades by the activation of Bim, Bid, Bax, Bak, Puma, caspases-3, -6, -7, -8 and PARP, and the protein expression levels of Bip, calnexin, PDI, calpain-2 and caspase-12 were also upregulated dramatically by neferine treatment.

These observations reveal that the therapeutic potential of neferine in treating HCC Hep3B cells, containing copies of hepatitis B virus (HBV) genomes (Yoon et al., 2013).

Osteosarcoma

It was found that neferine possessed a potent growth-inhibitory effect on human osteosarcoma cells, but not on non-neoplastic human osteoblast cells. The inhibitory effect of neferine on human osteosarcoma cells was largely attributed to cell-cycle arrest at G1. The up-regulation of p21 by neferine was due to an increase in the half-life of p21 protein. Zhang et al. (2012) showed that neferine treatment led to an increased phosphorylation of p21 at Ser130 that was dependent on p38. Their results for the first time showed a direct anti-tumor effect of neferine, suggesting that consumption of neferine may have cancer-preventive and cancer-therapeutic benefit.

Breast Cancer

Qualitative analysis showed that NLE contained several compounds, including polyphenols. The polyphenols identified in NLE consisted primarily of gallic acid, rutin, and quercetin. Cell cycle analysis revealed that breast cancer MCF-7 cells treated with NLE were arrested at the G0/G1 phase. In an in vivo analysis, treatment with NLE (0.5 and 1%) effectively reduced tumor volume and tumor weight in mice inoculated with MCF-7 cells compared to the control samples.

These results confirmed that cell-cycle arrest was sufficient to elicit tumor regression following NLE treatment (Yang et al., 2011).

Melanoma

Methanolic extracts from the flower buds and leaves of sacred lotus (Nelumbo nucifera) were found to show inhibitory effects on melanogenesis in theophylline-stimulated murine B16 melanoma 4A5 cells. 3-30 µM nuciferine and N-methylasimilobine inhibited the expression of tyrosinase mRNA, 3-30 µM N-methylasimilobine inhibited the expression of TRP-1 mRNA, and 10-30 µM nuciferine inhibited the expression of TRP-2 mRNA (Nakamura et al., 2013).

References

Nakamura S, Nakashima S, Tanabe G, et al. (2013). Alkaloid constituents from flower buds and leaves of sacred lotus (Nelumbo nucifera, Nymphaeaceae) with melanogenesis inhibitory activity in B16 melanoma cells. Bioorg Med Chem, 21(3):779-87. doi: 10.1016/j.bmc.2012.11.038.


Yang MY, Chang YC, Chan KC et al. (2011). Flavonoid-enriched extracts from Nelumbo nucifera leaves inhibits proliferation of breast cancer in vitro and in vivo. European Journal of Integrative Medicine, 3(3):153-163. doi:10.1016/j.eujim.2011.08.008


Yoon JS, Kim HM, Yadunandam AK, et al. (2013). Neferine isolated from Nelumbo nucifera enhances anti-cancer activities in Hep3B cells: Molecular mechanisms of cell-cycle arrest, ER stress induced apoptosis and anti-angiogenic response. Phytomedicine, 20(11):1013–1022. doi:10.1016/j.phymed.2013.03.024.


Zhang XY, Liu ZJ, Xu B, et al. (2012). Neferine, an alkaloid ingredient in lotus seed embryo, inhibits proliferation of human osteosarcoma cells by promoting p38 MAPK-mediated p21 stabilization. European Journal of Pharmacology, 677(1–3):47–54.

AhR, Akt, angiogenesis, Anti-cancer, anti-proliferative, anti-proliferative effect, anti-tumor, anti-tumor activity, apoptosis, Apoptotic, BCR, Breast cancer, CDK, CDK2, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, CYP1A1, CYP1B1, FAK, G1, G2/M, Head and neck cancer, inflammation, inhibits angiogenesis, Isatis (L.) genus, Lung cancer, MCF-7, metastasis, Prostate cancer, RS4;11 and MV4;1, STAT3

Indirubin

Cancer:
Chronic myelogenous leukemia, lung, breast, head and neck, prostate, acute myeloid leukemia, prostate

Action: Aryl hydrocarbon Receptor (AhR) regulator, inhibits angiogenesis

Indirubin is the active component of many plants from the Isatis (L.) genus, including Isatis tinctoria (L.).

Indirubin is the active ingredient of Danggui Longhui Wan, a mixture of plants that is used in traditional Chinese medicine to treat chronic diseases. Indirubin and its analogues are potent inhibitors of cyclin-dependent kinases (CDKs). The crystal structure of CDK2 in complex with indirubin derivatives shows that indirubin interacts with the kinase's ATP-binding site through van der Waals interactions and three hydrogen bonds. Indirubin-3'-monoxime inhibits the proliferation of a large range of cells, mainly through arresting the cells in the G2/M phase of the cell-cycle. These results have implications for therapeutic optimization of indigoids (Hoessel et al., 1999).

Formula; Huang Lian (Rhizoma Coptidis Recens), Huang Qin (Radix Scutellariae Baicalensis), Huang Bai (Cortex Phellodendri), Zhi Zi (Fructus Gardeniae Jasminoidis), Dang Gui (Radix Angelicae Sinensis), Lu Hui (Herba Aloes), Long Dan Cao (Radix Gentianae Longdancao), Da Huang (Radix et Rhizoma Rhei), Mu Xiang (Radix Aucklandiae Lappae), Qing Dai (Indigo Pulverata Levis), She Xiang (Secretio Moschus)

Leukemia

Indirubin, a 3, 2' bisindole isomer of indigo was originally identified as the active principle of a traditional Chinese preparation and has been proven to exhibit anti-leukemic effectiveness in chronic myelocytic leukemia. Indirubin was detected to represent a novel lead structure with potent inhibitory potential towards cyclin-dependent kinases (CDKs) resulting from high affinity binding into the enzymes ATP binding site. This seminal finding triggered research to improve the pharmacological activities of the parent molecule within comprehensive structure-activity studies. Molecular modifications made novel anti-cancer compounds accessible with strongly improved CDK inhibitory potential and with broad-spectrum anti-tumor activity.

This novel family of compounds holds strong promise for clinical anti-cancer activity and might be useful also in several important non-cancer indications, including Alzheimer's disease or diabetes (Eisenbrand et al., 2004).

Aryl Hydrocarbon Receptor (AhR) Regulator; Breast Cancer

The aryl hydrocarbon receptor (AhR), when activated by exogenous ligands such as 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), regulates expression of several phase I and phase II enzymes and is also involved in the regulation of cell proliferation. One putative endogenous ligand is indirubin, which was recently identified in human urine and bovine serum. We determined the effect of indirubin in MCF-7 breast cancer cells on induction of the activities of cytochromes P450 (CYP) 1A1 and 1B1. With 4 hours exposure, the effects of indirubin and TCDD at 10nM on CYP activity were comparable, but the effects of indirubin, unlike those of TCDD, were transitory. Indirubin-induced ethoxyresorufin-O-deethylase activity was maximal by 6–9 hours post-exposure and had disappeared by 24 hours, whereas TCDD-induced activities remained elevated for at least 72 hours.

Thus, if indirubin is an endogenous AhR ligand, then AhR-mediated signaling by indirubin is likely to be transient and tightly controlled by the ability of indirubin to induce CYP1A1 and CYP1B1, and hence its own metabolism (Spink et al., 2003).

Chronic Myelogenous Leukemia (CML)

Indirubin is the major active anti-tumor component of a traditional Chinese herbal medicine used for treatment of chronic myelogenous leukemia (CML). In a study investigating its mechanism of action, indirubin derivatives (IRDs) were found to potently inhibit Signal Transducer and Activator of Transcription 5 (Stat5) protein in CML cells.

Compound E804, which is the most potent in this series of IRDs, blocked Stat5 signaling in human K562 CML cells, imatinib-resistant human KCL-22 CML cells expressing the T315I mutant Bcr-Abl (KCL-22M), and CD34-positive primary CML cells from patients.

In sum, these findings identify IRDs as potent inhibitors of the SFK/Stat5 signaling pathway downstream of Bcr-Abl, leading to apoptosis of K562, KCL-22M and primary CML cells. IRDs represent a promising structural class for development of new therapeutics for wild type or T315I mutant Bcr-Abl-positive CML patients (Nam et al., 2012).

Lung Cancer

A novel indirubin derivative, 5'-nitro-indirubinoxime (5'-NIO), exhibits a strong anti-cancer activity against human cancer cells. Here, the 5'-NIO-mediated G1 cell-cycle arrest in lung cancer cells was associated with a decrease in protein levels of polo-like kinase 1 (Plk1) and peptidyl-prolyl cis/trans isomerase Pin1. These findings suggest that 5'-NIO have potential anti-cancer efficacy through the inhibition of Plk1 or/and Pin1 expression (Yoon et al., 2012).

The control lung tissue showed a normal architecture with clear alveolar spaces. Interestingly, the indirubin-3-monoxime treated groups showed reduced adenocarcinoma with appearance of alveolar spaces. Transmission Electron Microscopic (TEM) studies of lung sections of [B(α)P]-induced lung cancer mice showed the presence of phaemorphic cells with dense granules and increased mitochondria.

The lung sections of mice treated with indirubin-3-monoxime showed the presence of shrunken, fragmented, and condensed nuclei implying apoptosis. The effects were dose-dependent and prominent in 10 mg/kg/5 d/week groups, suggesting the therapeutic role of indirubin analogue against this deadly human malignancy. These results indicate that indirubin-3-monoxime brings anti-tumor effect against [B(α)P]-induced lung cancer by its apoptotic action in A/J mice (Ravichandran et al., 2010).

Head and Neck Cancer

The effects of 5'-nitro-indirubinoxime (5'-NIO), an indirubin derivative, on metastasis of head and neck cancer cells were investigated and the underlying molecular mechanisms involved in this process explored.

After treatment of head and neck cancer cells with 5'-NIO, cell metastatic behaviors such as colony formation, invasion, and migration were inhibited in a concentration-dependent manner. 5'-NIO inhibited the beta1 Integrin/FAK/Akt pathway which can then facilitate invasion and/or migration of cancer cells through the extracellular matrix (ECM). Moreover, treatment of head and neck cancer cell with Integrin β1 siRNA or FAK inhibitor effectively inhibited the invasion and migration, suggesting their regulatory role in invasiveness and migration of head and neck cancer cells. It was concluded that 5'-NIO inhibits the metastatic ability of head and neck cancer cells by blocking the Integrin β1/FAK/Akt pathway (Kim et al., 2011).

Prostate Cancer; Inhibits Angiogenesis

Indirubin, the active component of a traditional Chinese herbal medicine, Banlangen, has been shown to exhibit anti-tumor and anti-inflammation effects; however, its role in tumor angiogenesis, the key step involved in tumor growth and metastasis, and the involved molecular mechanism is unknown.

To address this shortfall in the existing research, it was identified that indirubin inhibited prostate tumor growth through inhibiting tumor angiogenesis. It was found that indirubin inhibited angiogenesis in vivo. The inhibition activity of indirubin in endothelial cell migration, tube formation and cell survival in vitro has also been shown. Furthermore, indirubin suppressed vascular endothelial growth factor receptor 2-mediated Janus kinase (JAK)/STAT3 signaling pathway. This study provided the first evidence for anti-tumor angiogenesis activity of indirubin and the related molecular mechanism.

These investigations suggest that indirubin is a potential drug candidate for angiogenesis-related diseases (Zhang et al., 2011).

Acute Myeloid Leukemia

Indirubin derivatives were identified as potent FLT3 tyrosine kinase inhibitors with anti-proliferative activity at acute myeloid leukemic cell lines, RS4;11 and MV4;11 which express FLT3-WT and FLT3-ITD mutation, respectively. Among several 5 and 5'-substituted indirubin derivatives, 5-fluoro analog, 13 exhibited potent inhibitory activity at FLT3 (IC(50)=15 nM) with more than 100-fold selectivity versus 6 other kinases and potent anti-proliferative effect for MV4;11 cells (IC(50)=72 nM) with 30-fold selectivity versus RS4;11 cells.

Cell cycle analysis indicated that compound 13 induced cell-cycle arrest at G(0)/G(1) phase in MV4;11 cells (Choi et al., 2010).

References

Choi SJ, Moon MJ, Lee SD, et al. (2010). Indirubin derivatives as potent FLT3 inhibitors with anti-proliferative activity of acute myeloid leukemic cells. Bioorg Med Chem Lett, 20(6):2033-7.


Eisenbrand G, Hippe F, Jakobs S, Muehlbeyer S. (2004). Molecular mechanisms of indirubin and its derivatives: novel anti-cancer molecules with their origin in traditional Chinese phytomedicine. J Cancer Res Clin Oncol, 130(11):627-35


Hoessel R, Leclerc S, Endicott JA, et al. (1999). Indirubin, the active constituent of a Chinese antileukaemia medicine, inhibits cyclin-dependent kinases. Nat Cell Biol, 1(1):60-7.


Kim SA, Kwon SM, Kim JA, et al. (2011). 5'-Nitro-indirubinoxime, an indirubin derivative, suppresses metastatic ability of human head and neck cancer cells through the inhibition of Integrin β 1/FAK/Akt signaling. Cancer Lett, 306(2):197-204.


Nam S, Scuto A, Yang F, et al. (2012). Indirubin derivatives induce apoptosis of chronic myelogenous leukemia cells involving inhibition of Stat5 signaling. Mol Oncol, 6(3):276-83.


Ravichandran K, Pal A, Ravichandran R. (2010). Effect of indirubin-3-monoxime against lung cancer as evaluated by histological and transmission electron microscopic studies. Microsc Res Tech, 73(11):1053-8.


Spink BC, Hussain MM, Katz BH, Eisele L, Spink DC. (2003). Transient induction of cytochromes P450 1A1 and 1B1 in MCF-7 human breast cancer cells by indirubin. Biochem Pharmacol, 66(12):2313-21.


Yoon HE, Kim SA, Choi HS, et al. (2012). Inhibition of Plk1 and Pin1 by 5'-nitro-indirubinoxime suppresses human lung cancer cells. Cancer Lett, 316(1):97-104.


Zhang X, Song Y, Wu Y, et al. (2011). Indirubin inhibits tumor growth by anti-tumor angiogenesis via blocking VEGFR2-mediated JAK/STAT3 signaling in endothelial cell. Int J Cancer, 129(10):2502-11. doi: 10.1002/ijc.25909.

angiogenesis, Anti-cancer, Anti-cancer effect, anti-tumor, anti-tumor activity, apoptosis, Apoptotic, BAX, Bcl-2, BCR, Breast cancer, CAM, CDC2, CDC25C, CDK4, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Endometrial cancer, ER, ER modulator, ERK, G2/M, Hec1A, KIP1, MCF-7, MCF7, MDA-MB-453, p16, p27, PC3, Pro-apoptotic, Radio-sensitizer, several species of the genus Epimedium

Icaritin

Cancer:
Endometrial., chronic myeloid leukemia, prostate, breast

Action: Radio-sensitizer, cell-cycle arrest, ER modulator

Icaritin is a compound in several species of the genus Epimedium (L.).

Cell-cycle Arrest

Icariin and icaritin with prenyl group have been demonstrated to have selective estrogen receptor modulating activities. Icaritin-induced growth inhibition was associated with G(1) arrest (P<0.05), and G(2)-M arrest depending upon doses. Consistent with G(1) arrest, icaritin increased protein expressions of pRb, p27(Kip1) and p16(Ink4a), while showing decrease in phosphorylated pRb, Cyclin D1 and CDK4.

Comparatively, icariin has much lower effects on PC-3 cells and showed only weak G(1) arrest, suggesting a possible structure-activity relationship. These findings suggested a novel anti-cancer efficacy of icaritin mediated selectively via induction of cell-cycle arrest but not associated with estrogen receptors in PC-3 cells (Huang et al., 2007).

Estrogen Receptor (ER) Modulator; Endometrial Cancer

Icaritin has selective estrogen receptor (ER) modulating activities, and posseses anti-tumor activity. The effect of icaritin on cell growth of human endometrial cancer Hec1A cells was investigated and it was found that icaritin potently inhibited proliferation of Hec1A cells. Icaritin also induced cell apoptosis accompanied by activation of caspases. Icaritin treatment also induced expression of pro-apoptotic protein Bax with a concomitant decrease of Bcl-2 expression.

These results demonstrate that icaritin induced sustained ERK 1/2 activation and inhibited growth of endometrial cancer Hec1A cells, and provided a rationale for preclinical and clinical evaluation of icaritin for endometrial cancer therapy (Tong et al., 2011).

Breast cancer

In research carried out to probe breast cancer cell growth mechanisms, icaritin has been found to strongly inhibit the growth of breast cancer MDA-MB-453 and MCF7 cells. At concentrations of 2–3 µM, icaritin induced cell-cycle arrest at the G2/M phase accompanied by a down-regulation of the expression levels of the G2/M regulatory proteins such as cyclinB, cdc2 and cdc25C.

Icaritin at concentrations of 4–5 µM, however, induced apoptotic cell death. In addition, icaritin also induced a sustained phosphorylation of extracellular signal-regulated kinase (ERK) in these breast cancer cells.

Icaritin more potently inhibited growth of the breast cancer stem/progenitor cells compared to anti-estrogen tamoxifen. These results indicate that icaritin is a potent growth inhibitor for breast cancer cells and provides a rationale for preclinical and clinical evaluations of icaritin for breast cancer therapy (Guo et al., 2011).

Radio-sensitizer

The combination of Icaritin at 3 µM or 6 µM with 6 or 8 Gy of ionizing radiation (IR) in the clonogenic assay yielded an ER (enhancement ratio) of 1.18 or 1.28, CI (combination index) of 0.38 or 0.19 and DRI (dose reducing index) of 2.51 or 5.07, respectively. These findings strongly suggest that Icaritin exerted a synergistic killing effect with radiation on the tumor cells. It suppressed angiogenesis in chick embryo chorioallantoic membrane (CAM) assay. These results, taken together, indicate Icaritin is a new radio-sensitizer and can enhance anti-cancer effect of IR or other therapies (Hong et al., 2013).

Chronic Myeloid Leukemia (CML)

The mechanism of anti-leukemia for Icaritin is involved in the regulation of Bcr/Abl downstream signaling. Icaritin may be useful for an alternative therapeutic choice of Imatinib-resistant forms of CML. Icaritin potently inhibited proliferation of K562 cells (IC50 was 8 µM) and primary CML cells (IC50 was 13.4 µM for CML-CP and 18 µM for CML-BC), induced CML cells apoptosis, and promoted the erythroid differentiation of K562 cells in a time-dependent manner. Furthermore, Icaritin was able to suppress the growth of primary CD34+ leukemia cells (CML) and Imatinib-resistant cells, and to induce apoptosis (Zhu et al., 2011).

References

Guo YM, Zhang XT, Meng J, Wang ZY. (2011). An anti-cancer agent icaritin induces sustained activation of the extracellular signal-regulated kinase (ERK) pathway and inhibits growth of breast cancer cells. European Journal of Pharmacology, 658(2–3):114–122. doi:10.1016/j.ejphar.2011.02.005.


Hong J, Zhang Z, Lv W, et al. (2013). Icaritin Synergistically Enhances the Radiosensitivity of 4T1 Breast Cancer Cells. PLoS One, 8(8):e71347. doi: 10.1371/journal.pone.0071347.


Huang X, Zhu D, Lou Y. (2007). A novel anti-cancer agent, icaritin, induced cell growth inhibition, G1 arrest and mitochondrial transmembrane potential drop in human prostate carcinoma PC-3 cells. Eur J Pharmacol, 564(1-3):26-36.


Tong JS, Zhang QH, Huang X, et al. (2011). Icaritin Causes Sustained ERK1/2 Activation and Induces Apoptosis in Human Endometrial Cancer Cells. PLoS ONE, 6(3): e16781. doi:10.1371/journal.pone.0016781.


Zhu JF, Li ZJ, Zhang GS, et al. (2011). Icaritin shows potent anti-leukemia activity on chronic myeloid leukemia in vitro and in vivo by regulating MAPK/ERK/JNK and JAK2/STAT3 /AKT signalings. PLoS One, 6(8):e23720. doi: 10.1371/journal.pone.0023720.

anti-tumor, anti-tumor activity, apoptosis, Cephalotaxus harringtonia, Chapter 7 Isolates and Cancer Research, cytotoxic, induces apoptosis

Homoharringtonine/Omacetaxine

Cancer:
Leukemia, AML, CML, myelodysplastic syndrome (MDS)

Action: Induces apoptosis, anti-tumor activity

Homoharringtonine (also known as Omacetaxine mepesuccinate) is isolated from Cephalotaxus harringtonia (K.Koch).

Homoharringtonine/omacetaxine is a unique agent with a long history of research development. It has been recently approved by the Food and Drug Administration for the treatment of chronic myeloid leukemia after failure of 2 or more tyrosine kinase inhibitors. Research with this agent has spanned over 40 years (Kantarjian, O'Brien, & Cortes, 2013).

Leukemia

Homoharringtonine (HHT), first isolated from the Chinese evergreen Cephalotaxus harringtonia, has been demonstrated to have a broad anti-tumor activity in rodents and anti-leukemic effects in humans. It was found that HHT was metabolized to an acid product [HHT acid; 2'hydroxy2' (acetic acid) 6'hydroxy6'methylheptanoyl cephalotaxine] when incubated with either human plasma or mouse plasma in vitro. The HHT concentration inhibiting 50% of the growth of human leukemic HL60 cells was 20 ng/ml, while for HHT acid it was 14,500 ng/ml, indicating that the acid form was more than 700 times less cytotoxic than HHT. The lethal dose of HHT affecting 50%(LD50) of mice was 6.7 mg/kg, but HHT acid produced no apparent toxic effects at doses up to 280 mg/kg (Ni et al., 2003).

Acute Myeloid Leukemia (AML)

The response to remission induction in elderly patients with acute myeloid leukemia (AML) remains poor. Patients were treated with the HA regimen consisting of homoharringtonine (2 mg/m2/day for 7 days) and cytarabine (Ara-C, 100 mg/m2/day for 7 days). The overall response rate was 56.5% with complete remission (CR) rate of 39.1% and partial remission of 17.4%.

There was no early death in this cohort of patients. The estimated median overall survival (OS) time of all patients was (12.0 ± 3.0) months. The estimated OS time of the CR patients was 15 months. The estimated one-year OS rate of all patients treated with HA protocol was (49.3 ± 13.5) %. The estimated one-year OS rate of the CR patients was (62.5 ± 17.1) % (Wang et al., 2009).

Leukemia; Telomerase

The effect of HHT on the telomerase activity and apoptosis of human leukemia HL-60 cells was investigated. Telomerase activity of HL-60 cells was examined by the telomeric repeat amplification protocol (TRAP)–an enzyme-linked immunosorbent assay (ELISA). Apoptosis was analyzed by morphological observation, DNA agarose gel electrophoresis, flow cytometry (FCM), and TdT-mediated dUTP-biotin nick end labeling (TUNEL).

After treatment with HHT at 5-500 microg/l for 48 hours, the level of telomerase activity in HL-60 cells decreased in a dose-and time-dependent manner. Simultaneously, HL-60 cells underwent apoptosis. In conclusion, these data suggest that HHT can inhibit the telomerase content of HL- 60 cells effectively and induce apoptosis (Xie et al., 2006).

Chronic Myeloid Leukemia (CML)

Evidence confirmed HHT as an apoptosis inducer in tumor cell lines and fresh cells from cancer patients. The CR rate reported with HHT-based regimen in acute nonlymphocytic leukemia showed no statistical differences from that with DNR-based regimen, although the case number was limited.

Although with anti-growth activity in vitro and laudable achievement in acute and chronic myeloid leukemia treatment, the drug shows no beneficial effect in lymphocytic leukemia and solid tumors. The underlying mechanism for the discrepancy of efficacy remains unknown, and is a subject for further research (Luo et al., 2004).

Myelodysplastic Syndrome (MDS)

Homoharringtonine might have clinical activity in some patients with myelodysplastic syndrome (MDS) (Daver et al., 2013).

References

Daver N, Vega-Ruiz A, Kantarjian HM, et al. (2013). A phase II open-label study of the intravenous administration of homoharringtonine in the treatment of myelodysplastic syndrome. Eur J Cancer Care, 22(5):605-11. doi: 10.1111/ecc.12065.


Kantarjian HM, O'Brien S, Cortes J. (2013). Homoharringtonine/Omacetaxine mepesuccinate: the long and winding road to food and drug administration approval. Clin Lymphoma Myeloma Leuk, 13(5):530-3. doi: 10.1016/j.clml.2013.03.017.


Luo CY, Tang JY, Wang YP. (2004). Homoharringtonine: a new treatment option for myeloid leukemia. Hematology, 9(4):259-70.


Ni D, Ho DH, Vijjeswarapu M, et al. (2003). Metabolism of homoharringtonine, a cytotoxic component of the evergreen plant Cephalotaxus harringtonia. Journal of Experimental Therapeutics and Oncology, 3(1):47.


Wang J, LŸ S, Yang J, et al. (2009). A homoharringtonine-based induction regimen for the treatment of elderly patients with acute myeloid leukemia: a single center experience from China. Journal of Hematology & Oncology, 2:32. doi:10.1186/1756-8722-2-32


Xie WZ, Lin MF, Huang H, Cai Z. (2006). Homoharringtonine-induced apoptosis of human leukemia HL-60 cells is associated with down-regulation of telomerase. Am J Chin Med, 34(2):233-44.

AGS, anti-tumor, anti-tumor activity, apoptosis, BAX, Bcl-2, Breast cancer, Breast cancer cell lines, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, G0/G1, G1, G2/M, MCF-7, MDA-MB-231, PARP, PCNA, Rhizoma curcuma longa, S

Germacrone

Cancer: Breast, stomach

Action: Cell-cycle arrest

Traditional medicinal herbs are an untapped source of potential pharmaceutical compounds. Germacrone is a natural product isolated from Rhizoma curcuma longa (L.).

Breast Cancer

Germacrone has been investigated for its inhibition on the proliferation of breast cancer cell lines. Germacrone treatment significantly inhibited cell proliferation, increased lactate dehydrogenase (LDH) release, and induced mitochondrial membrane potential (ΔΨ m) depolarization in both MCF-7 and MDA-MB-231 cells in a dose-dependent manner. Germacrone induced MDA-MB-231 and MCF-7 cell-cycle arrest at the G0/G1 and G2/M phases respectively and induced MDA-MB-231 cell apoptosis.

In addition, germacrone treatment induced caspase-3, 7, 9, PARP cleavage. It was therefore concluded that germacrone inhibited the proliferation of breast cancer cell lines by inducing cell-cycle arrest and apoptosis through mitochondria-mediated caspase pathway. These results might provide some molecular basis for the anti-tumor activity of Rhizoma curcuma (Zhong et al., 2011).

Stomach Cancer

Germacrone, contained in zedoary oil from Rhizoma curcuma, significantly decreased the cell viability of AGS cells (P < 0.01) and MGC 803 cells (P < 0.01), and the inhibitory effects were attenuated by elevated concentrations of FBS. At high concentrations (>=90 mug/mL), zedoary oil killed GES-1 cells. At low concentrations (<=60 mug/mL), zedoary oil was less inhibitory toward gastric cancer cell lines. In AGS cells, zedoary oil inhibited cell proliferation in a dose- and time-dependent manner, with decreased PCNA protein expression in the zedoary oil-treated cells, and arrested the cell-cycle at S, G2/M and G0/G1 stages after treatment for 6–48 hours. At concentrations of 30, 60 and 90 mug/mL, which resulted in significant inhibition of proliferation and cell-cycle arrest, zedoary oil induced cell apoptosis.

Zedoary oil up-regulated the ratio of Bax/Bcl-2 protein expression (P < 0.01). Zedoary oil which contains germacrone was hence found to inhibit AGS cell proliferation through cell-cycle arrest and cell apoptosis promotion, which are related to Bax/Bcl-2 protein expression.

References

Shi H, Tan B, Ji G, et al. (2013). Zedoary oil (Ezhu You) inhibits proliferation of AGS cells. Chin Med, 8(1):13.


Zhong Z, Chen X, Tan W, et al. (2011). Germacrone inhibits the proliferation of breast cancer cell lines by inducing cell-cycle arrest and promoting apoptosis. Eur J Pharmacol, 667(1-3):50-55. doi:10.1016/j.ejphar.2011.03.041.

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.

anti-apoptotic, Anti-cancer, anti-inflammatory, anti-oxidative, anti-proliferative, anti-tumor, anti-tumor activity, apoptosis, Apoptotic, AR, BAX, Bcl-2, Bcl-xL, Breast cancer, cell-cycle arrest, Cervical cancer, Chapter 7 Isolates and Cancer Research, COX-2, CYP3A, DU145, G1, G2/M, hepato-protective, ICAM-1, inflammation, JNK, MAPK, metastasis, MMP2, MMP9, MTOR, p38, PGE2, Prostate cancer, STAT3, STAT3 (Tyr705), TNF, VCAM-1

Cryptotanshinone (See also Tanshinone)

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

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

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

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

Anti-proliferative Agent

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

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

Anti-inflammatory; COX-2, PGE2

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

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

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

Prostate Cancer

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

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

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

Prostate Cancer; Androgen Receptor Positive

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

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

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

Breast Cancer, Cervical Cancer, Leukemia, Hepatocellular Carcinoma

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

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

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

Breast Cancer

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

Hepato-protective Effect

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

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

References

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

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

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

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

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

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

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

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

Shin DS, Kim HN, Shin KD, et al. (2009). Cryptotanshinone Inhibits Constitutive Signal Transducer and Activator of Transcription 3 Function through Blocking the Dimerization in DU145 Prostate Cancer Cells. Cancer Research, 69:193. doi: 10.1158/0008-5472.CAN-08-2575

Wang X, Morris-Natschke SL, Lee KH. (2007). New developments in the chemistry and biology of the bioactive constituents of Tanshen. Med Res Rev, 27:133–148. doi: 10.1002/med.20077.

Xu D, Lin TH, Li S, Da J, et al. (2012). Cryptotanshinone suppresses androgen receptor-mediated growth in androgen dependent and castration resistant prostate cancer cells. Cancer Lett, 316(1):11-22. doi: 10.1016/j.canlet.2011.10.006.

Xu YX, Feng T, Li R, Liu ZC. (2009). Tanshinone II-A inhibits invasion and metastasis of human hepatocellular carcinoma cells in vitro and in vivo. Tumori, 95:789–795.

Akt, anti-inflammatory, anti-tumor, anti-tumor activity, apoptosis, Caesalpinia coriaria, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, cytotoxic, ERK, G2/M, Hep3B, hepato-protective, Ovarian cancer, Ovarian cancer cell lines, Phyllanthus niruri, Punica granatum, Radio-protective, SKOv3ip,Hey and HO-8910PM

Corilagin

Cancer: Ovarian, hepatocellular carcinoma

Action: Radio-protective

Corilagin is isolated from Phyllanthus niruri (L.), Punica granatum (Linnaeus), Caesalpinia coriaria [(Jacq.) Willd.], Alchornea glandulosa (Poepp. & Endl.).

Ovarian Cancer

Phyllanthus niruri L. is a well-known hepato-protective and anti-viral medicinal herb. Recently, Jia et al. (2013) identified Corilagin as a major active component with anti-tumor activity in this herbal medicine. Corilagin is a member of the tannin family that has been discovered in many medicinal plants and has been used as an anti-inflammatory agent.

The ovarian cancer cell lines SKOv3ip, Hey and HO-8910PM were treated with Corilagin. Corilagin inhibited the growth of the ovarian cancer cell lines SKOv3ip and Hey, with IC50 values of less than 30 muM, while displaying low toxicity against normal ovarian surface epithelium cells, with IC50 values of approximately 160 muM. Corilagin induced cell-cycle arrest at the G2/M stage and enhanced apoptosis in ovarian cancer cells.

In contrast, a reduction of TGF-beta secretion was not observed in cancer cells treated with the cytotoxic drug Paclitaxel, suggesting that Corilagin specifically targets TGF-beta secretion. Corilagin blocked the activation of both the canonical Smad and non-canonical ERK/AKT pathways.

Corilagin extracted from Phyllanthus niruri L. acts as a natural., effective therapeutic agent against the growth of ovarian cancer cells via targeted action against the TGF-beta/AKT/ERK/Smad signaling pathways (Jia et al., 2013).

Hepatocellular Carcinoma

Corilagin is considerably effective to retard the in vivo growth of xenografted Hep3B hepatocellular carcinoma. A significant inhibition of tumor growth was observed when treated mice are compared with control groups. Furthermore, analysis of enzymes markers of liver function, including alanine aminotransferase and asparate aminotransferase, suggested that current therapeutic dosage of corilagin did not exert adverse effect on liver (Hau et al., 2010).

Radio-protective

Corilagin, a member of the tannin family, inhibits NF-kappaB pathway activation. In the present study, Dong et al. (2010) examined the inhibitory effects of corilagin on radiation-induced microglia activation. Their data suggest that corilagin inhibits radiation-induced microglia activation via suppression of the NF-kappaB pathway and the compound is a potential treatment for radiation-induced brain injury (RIBI) (Dong et al., 2010).

References

Dong XR, Luo M, Fan L, et al. (2010). Corilagin inhibits the double strand break-triggered NF-kappaB pathway in irradiated microglial cells. Int J Mol Med, 25(4):531-6.


Hau DK, Zhu GY, Leung AK, et al. (2010) In vivo anti-tumor activity of corilagin on Hep3B hepatocellular carcinoma. Phytomedicine, 18(1):11-5. doi: 10.1016/j.phymed.2010.09.001.


Jia LQ, Jin HY, Zhou JY, et al. (2013). A potential anti-tumor herbal medicine, Corilagin, inhibits ovarian cancer cell growth through blocking the TGF-β signaling pathways. BMC Complementary and Alternative Medicine, 13:33. doi:10.1186/1472-6882-13-33

A549 cells, angiogenesis, Anti-angiogenesis, Anti-angiogenic, anti-apoptotic, Anti-cancer, Anti-cancer effect, anti-inflammatory, anti-oxidant, anti-proliferative, anti-proliferative effect, anti-tumor, anti-tumor activity, apoptosis, Apoptotic, BAX, Bcl-2, Bcl-xL, c-Jun, CAM, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Chemotherapy, cytotoxic, DUBs, G0/G1, G1, G1/S, Glioblastoma, growth-inhibitory, HT-29, IL-2, Immune, induces apoptosis, Ki-67, Leukemia, Lung cancer, MAPK, Mcl-1, Medulloblastoma, Melanoma, metastasis, Neuroblastoma, Nitric Oxide, Ovarian cancer, p21, p38, p53, Pancreatic cancer, Pro-apoptotic, Prostate cancer, radiotherapy, Rectal cancer, Rhabdomyosarcoma, ROS, Sarcoma, SK-N-AS, TNF, VEGF, VEGF

Betulin and Betulinic acid

Cancer:
Neuroblastoma, medulloblastoma, glioblastoma, colon, lung, oesophageal, leukemia, melanoma, pancreatic, prostate, breast, head & neck, myeloma, nasopharyngeal, cervical, ovarian, esophageal squamous carcinoma

Action: Anti-angiogenic effects, induces apoptosis, anti-oxidant, cytotoxic and immunomodifying activities

Betulin is a naturally occurring pentacyclic triterpene found in many plant species including, among others, in Betula platyphylla (white birch tree), Betula X caerulea [Blanch. (pro sp.)], Betula cordifolia (Regel), Betula papyrifera (Marsh.), Betula populifolia (Marsh.) and Dillenia indica L . It has anti-retroviral., anti-malarial., and anti-inflammatory properties, as well as a more recently discovered potential as an anti-cancer agent, by inhibition of topoisomerase (Chowdhury et al., 2002).

Betulin is found in the bark of several species of plants, principally the white birch (Betula pubescens ) (Tan et al., 2003) from which it gets its name, but also the ber tree (Ziziphus mauritiana ), selfheal (Prunella vulgaris ), the tropical carnivorous plants Triphyophyllum peltatum and Ancistrocladus heyneanus, Diospyros leucomelas , a member of the persimmon family, Tetracera boiviniana , the jambul (Syzygium formosanum ) (Zuco et al., 2002), flowering quince (Chaenomeles sinensis ) (Gao et al., 2003), rosemary (Abe et al., 2002) and Pulsatilla chinensis (Ji et al., 2002).

Anti-cancer, Induces Apoptosis

The in vitro characterization of the anti-cancer activity of betulin in a range of human tumor cell lines (neuroblastoma, rhabdomyosarcoma-medulloblastoma, glioma, thyroid, breast, lung and colon carcinoma, leukaemia and multiple myeloma), and in primary tumor cultures isolated from patients (ovarian carcinoma, cervical carcinoma and glioblastoma multiforme) was carried out to probe its anti-cancer effect. The remarkable anti-proliferative effect of betulin in all tested tumor cell cultures was demonstrated. Furthermore, betulin altered tumor cell morphology, decreased their motility and induced apoptotic cell death. These findings demonstrate the anti-cancer potential of betulin and suggest that it may be applied as an adjunctive measure in cancer treatment (Rzeski, 2009).

Lung Cancer

Betulin has also shown anti-cancer activity on human lung cancer A549 cells by inducing apoptosis and changes in protein expression profiles. Differentially expressed proteins explained the cytotoxicity of betulin against human lung cancer A549 cells, and the proteomic approach was thus shown to be a potential tool for understanding the pharmacological activities of pharmacophores (Pyo, 2009).

Esophageal Squamous Carcinoma

The anti-tumor activity of betulin was investigated in EC109 cells. With the increasing doses of betulin, the inhibition rate of EC109 cell growth was increased, and their morphological characteristics were changed significantly. The inhibition rate showed dose-dependent relation.

Leukemia

Betulin hence showed potent inhibiting effects on EC109 cells growth in vitro (Cai, 2006).

A major compound of the methanolic extract of Dillenia indica L. fruits, betulinic acid, showed significant anti-leukaemic activity in human leukaemic cell lines U937, HL60 and K562 (Kumar, 2009).

Betulinic acid effectively induces apoptosis in neuroectodermal and epithelial tumor cells and exerts little toxicity in animal trials. It has been shown that betulinic acid induced marked apoptosis in 65% of primary pediatric acute leukemia cells and all leukemia cell lines tested. When compared for in vitro efficiency with conventionally used cytotoxic drugs, betulinic acid was more potent than nine out of 10 standard therapeutics and especially efficient in tumor relapse. In isolated mitochondria, betulinic acid induced release of both cytochrome c and Smac. Taken together, these results indicated that betulinic acid potently induces apoptosis in leukemia cells and should be further evaluated as a future drug to treat leukemia (Ehrhardt, 2009).

Multiple Myeloma

The effect of betulinic acid on the induction apoptosis of human multiple myeloma RPMI-8226 cell line was investigated. The results showed that within a certain concentration range (0, 5, 10, 15, 20 microg/ml), IC50 of betulinic acid to RPMI-8226 at 24 hours was 10.156+/-0.659 microg/ml, while the IC50 at 48 hours was 5.434+/-0.212 microg/ml, and its inhibiting effect on proliferation of RPMI-8226 showed both a time-and dose-dependent manner.

It is therefore concluded that betulinic acid can induce apoptosis of RPMI-8226 within a certain range of concentration in a time- and dose-dependent manner. This phenomenon may be related to the transcriptional level increase of caspase 3 gene and decrease of bcl-xl. Betulinic acid also affects G1/S in cell-cycle which arrests cells at phase G0/G1 (Cheng, 2009).

Anti-angiogenic Effects, Colorectal Cancer

Betulinic acid isolated from Syzygium campanulatum Korth (Myrtaceae) was found to have anti-angiogenic effects on rat aortic rings, matrigel tube formation, cell proliferation and migration, and expression of vascular endothelial growth factor (VEGF). The anti-tumor effect was studied using a subcutaneous tumor model of HCT 116 colorectal carcinoma cells established in nude mice. Anti-angiogenesis studies showed potent inhibition of microvessels outgrowth in rat aortic rings, and studies on normal and cancer cells did not show any significant cytotoxic effect.

In vivo anti-angiogenic study showed inhibition of new blood vessels in chicken embryo chorioallantoic membrane (CAM), and in vivo anti-tumor study showed significant inhibition of tumor growth due to reduction of intratumor blood vessels and induction of cell death. Collectively, these results indicate betulinic acid as an anti-angiogenic and anti-tumor candidate (Aisha, 2013).

Nasopharyngeal Carcinoma Melanoma, Leukemia, Lung, Colon, Breast,Prostate, Ovarian Cancer

Betulinic acid is an effective and potential anti-cancer chemical derived from plants. Betulinic acid can kill a broad range of tumor cell lines, but has no effect on untransformed cells. The chemical also kills melanoma, leukemia, lung, colon, breast, prostate and ovarian cancer cells via induction of apoptosis, which depends on caspase activation. However, no reports are yet available about the effects of betulinic acid on nasopharyngeal carcinoma (NPC), a widely spread malignancy in the world, especially in East Asia.

In a study, Liu & Luo (2012) showed that betulinic acid can effectively kill CNE2 cells, a cell line derived from NPC. Betulinic acid-induced CNE2 apoptosis was characterized by typical apoptosis hallmarks: caspase activation, DNA fragmentation, and cytochrome c release.

These observations suggest that betulinic acid may serve as a potent and effective anti-cancer agent in NPC treatment. Further exploration of the mechanism of action of betulinic acid could yield novel breakthroughs in anti-cancer drug discovery.

Cervical Carcinoma

Betulinic acid has shown anti-tumor activity in some cell lines in previous studies. Its anti-tumor effect and possible mechanisms were investigated in cervical carcinoma U14 tumor-bearing mice. The results showed that betulinic acid (100 mg/kg and 200 mg/kg) effectively suppressed tumor growth in vivo. Compared with the control group, betulinic acid significantly improved the levels of IL-2 and TNF-alpha in tumor-bearing mice and increased the number of CD4+ lymphocytes subsets, as well as the ratio of CD4+/CD8+ at a dose of 200 mg/kg.

Furthermore, treatment with betulinic acid induced cell apoptosis in a dose-dependent manner in tumor-bearing mice, and inhibited the expression of Bcl-2 and Ki-67 protein while upregulating the expression of caspase-8 protein. The mechanisms by which BetA exerted anti-tumor effects might involve the induction of tumor cell apoptosis. This process is also related to improvement in the body's immune response (Wang, 2012).

Anti-oxidant, Cytotoxic and Immunomodifying Activities

Betulinic acid exerted cytotoxic activity through dose-dependent impairment of viability and mitochondrial activity of rat insulinoma m5F (RINm5F) cells. Decrease of RINm5F viability was mediated by nitric oxide (NO)-induced apoptosis. Betulinic acid also potentiated NO and TNF-α release from macrophages therefore enhancing their cytocidal action. The rosemary extract developed more pronounced anti-oxidant, cytotoxic and immunomodifying activities, probably due to the presence of betulinic acid (Kontogianni, 2013).

Pancreatic Cancer

Lamin B1 is a novel therapeutic target of Betulinic Acid in pancreatic cancer. The role and regulation of lamin B1 (LMNB1) expression in human pancreatic cancer pathogenesis and betulinic acid-based therapy was investigated. Lamin proteins are thought to be involved in nuclear stability, chromatin structure and gene expression. Elevation of circulating LMNB1 marker in plasma could detect early stages of HCC patients, with 76% sensitivity and 82% specificity. Lamin B1 is a clinically useful biomarker for early stages of HCC in tumor tissues and plasma (Sun, 2010).

It was found that lamin B1 was significantly down-regulated by BA treatment in pancreatic cancer in both in vitro culture and xenograft models. Overexpression of lamin B1 was pronounced in human pancreatic cancer and increased lamin B1 expression was directly associated with low grade differentiation, increased incidence of distant metastasis and poor prognosis of pancreatic cancer patients.

Furthermore, knockdown of lamin B1 significantly attenuated the proliferation, invasion and tumorigenicity of pancreatic cancer cells. Lamin B1 hence plays an important role in pancreatic cancer pathogenesis and is a novel therapeutic target of betulinic acid treatment (Li, 2013).

Multiple Myeloma, Prostate Cancer

The inhibition of the ubiquitin-proteasome system (UPS) of protein degradation is a valid anti-cancer strategy and has led to the approval of bortezomib for the treatment of multiple myeloma. However, the alternative approach of enhancing the degradation of oncoproteins that are frequently overexpressed in cancers is less developed. Betulinic acid (BA) is a plant-derived small molecule that can increase apoptosis specifically in cancer but not in normal cells, making it an attractive anti-cancer agent.

Results in prostate cancer suggest that BA inhibits multiple deubiquitinases (DUBs), which results in the accumulation of poly-ubiquitinated proteins, decreased levels of oncoproteins, and increased apoptotic cell death. In the TRAMP transgenic mouse model of prostate cancer, treatment with BA (10 mg/kg) inhibited primary tumors, increased apoptosis, decreased angiogenesis and proliferation, and lowered androgen receptor and cyclin D1 protein.

BA treatment also inhibited DUB activity and increased ubiquitinated proteins in TRAMP prostate cancer but had no effect on apoptosis or ubiquitination in normal mouse tissues. Overall, this data suggests that BA-mediated inhibition of DUBs and induction of apoptotic cell death specifically in prostate cancer but not in normal cells and tissues may provide an effective non-toxic and clinically selective agent for chemotherapy (Reiner, 2013).

Melanoma

Betulinic acid was recently described as a melanoma-specific inducer of apoptosis, and it was investigated for its comparable efficacy against metastatic tumors and those in which metastatic ability and 92-kD gelatinase activity had been decreased by introduction of a normal chromosome 6. Human metastatic C8161 melanoma cells showed greater DNA fragmentation and growth arrest and earlier loss of viability in response to betulinic acid than their non-metastatic C8161/neo 6.3 counterpart.

These effects involved induction of p53 without activation of p21WAF1 and were synergized by bromodeoxyuridine in metastatic Mel Juso, with no comparable responses in non-metastatic Mel Juso/neo 6 cells. These data suggest that betulinic acid exerts its inhibitory effect partly by increasing p53 without a comparable effect on p21WAF1 (Rieber, 1998).

As a result of bioassay–guided fractionation, betulinic acid has been identified as a melanoma-specific cytotoxic agent. In follow-up studies conducted with athymic mice carrying human melanomas, tumor growth was completely inhibited without toxicity. As judged by a variety of cellular responses, anti-tumor activity was mediated by the induction of apoptosis. Betulinic acid is inexpensive and available in abundant supply from common natural sources, notably the bark of white birch trees. The compound is currently undergoing preclinical development for the treatment or prevention of malignant melanoma (Pisha, 1995).

Betulinic acid strongly and consistently suppressed the growth and colony-forming ability of all human melanoma cell lines investigated. In combination with ionizing radiation the effect of betulinic acid on growth inhibition was additive in colony-forming assays.

Betulinic acid also induced apoptosis in human melanoma cells as demonstrated by Annexin V binding and by the emergence of cells with apoptotic morphology. The growth-inhibitory action of betulinic acid was more pronounced in human melanoma cell lines than in normal human melanocytes.

The properties of betulinic acid make it an interesting candidate, not only as a single agent but also in combination with radiotherapy. It is therefore concluded that the strictly additive mode of growth inhibition in combination with irradiation suggests that the two treatment modalities may function by inducing different cell death pathways or by affecting different target cell populations (Selzer, 2000).

Betulinic acid has been demonstrated to induce programmed cell death with melanoma and certain neuroectodermal tumor cells. It has been demonstrated currently that the treatment of cultured UISO-Mel-1 (human melanoma cells) with betulinic acid leads to the activation of p38 and stress activated protein kinase/c-Jun NH2-terminal kinase (a widely accepted pro-apoptotic mitogen-activated protein kinases (MAPKs)) with no change in the phosphorylation of extracellular signal-regulated kinases (anti-apoptotic MAPK). Moreover, these results support a link between the MAPKs and reactive oxygen species (ROS).

These data provide additional insight in regard to the mechanism by which betulinic acid induces programmed cell death in cultured human melanoma cells, and it likely that similar responses contribute to the anti-tumor effect mediated with human melanoma carried in athymic mice (Tan, 2003).

Glioma

Betulinic acid triggers apoptosis in five human glioma cell lines. Betulinic acid-induced apoptosis requires new protein, but not RNA, synthesis, is independent of p53, and results in p21 protein accumulation in the absence of a cell-cycle arrest. Betulinic acid-induced apoptosis involves the activation of caspases that cleave poly(ADP ribose)polymerase.

Betulinic acid induces the formation of reactive oxygen species that are essential for BA-triggered cell death. The generation of reactive oxygen species is blocked by BCL-2 and requires new protein synthesis but is unaffected by caspase inhibitors, suggesting that betulinic acid toxicity sequentially involves new protein synthesis, formation of reactive oxygen species, and activation of crm-A-insensitive caspases (Wolfgang, 1999).

Head and Neck Carcinoma

In two head and neck squamous carcinoma (HNSCC) cell lines betulinic acid induced apoptosis, which was characterized by a dose-dependent reduction in cell numbers, emergence of apoptotic cells, and an increase in caspase activity. Western blot analysis of the expression of various Bcl-2 family members in betulinic acid–treated cells showed, surprisingly, a suppression of the expression of the pro-apoptotic protein Bax but no changes in Mcl-1 or Bcl-2 expression.

These data clearly demonstrate for the first time that betulinic acid has apoptotic activity against HNSCC cells (Thurnher et al., 2003).

References

Abe F, Yamauchi T, Nagao T, et al. (2002). Ursolic acid as a trypanocidal constituent in rosemary. Biological & Pharmaceutical Bulletin, 25(11):1485–7. doi:10.1248/bpb.25.1485. PMID 12419966.


Aisha AF, Ismail Z, Abu-Salah KM, et al. (2013). Syzygium campanulatum korth methanolic extract inhibits angiogenesis and tumor growth in nude mice. BMC Complement Altern Med,13:168. doi: 10.1186/1472-6882-13-168.


Cai WJ, Ma YQ, Qi YM et al. (2006). Ai bian ji bian tu bian can kao wen xian ge shi    Carcinogenesis,Teratogenesis & Mutagenesis,18(1):16-8.


Cheng YQ, Chen Y, Wu QL, Fang J, Yang LJ. (2009). Zhongguo Shi Yan Xue Ye Xue Za Zhi, 17(5):1224-9.


Chowdhury AR, Mandal S, Mittra B, et al. (2002). Betulinic acid, a potent inhibitor of eukaryotic topoisomerase I: identification of the inhibitory step, the major functional group responsible and development of more potent derivatives. Medical Science Monitor, 8(7): BR254–65. PMID 12118187.


Ehrhardt H, Fulda S, FŸhrer M, Debatin KM & Jeremias I. (2004). Betulinic acid-induced apoptosis in leukemia cells. Leukemia, 18:1406–1412. doi:10.1038/sj.leu.2403406


Gao H, Wu L, Kuroyanagi M, et al. (2003). Anti-tumor-promoting constituents from Chaenomeles sinensis KOEHNE and their activities in JB6 mouse epidermal cells. Chemical & Pharmaceutical Bulletin, 51(11):1318–21. doi:10.1248/cpb.51.1318. PMID 14600382.


Ji ZN, Ye WC, Liu GG, Hsiao WL. (2002). 23-Hydroxybetulinic acid-mediated apoptosis is accompanied by decreases in bcl-2 expression and telomerase activity in HL-60 Cells. Life Sciences, 72(1):1–9. doi:10.1016/S0024-3205(02)02176-8. PMID 12409140.


Kontogianni VG, Tomic G, Nikolic I, et al. (2013). Phytochemical profile of Rosmarinus officinalis and Salvia officinalis extracts and correlation to their anti-oxidant and anti-proliferative activity. Food Chem,136(1):120-9. doi: 10.1016/j.foodchem.2012.07.091.


Kumar D, Mallick S, Vedasiromoni JR, Pal BC. (2010). Anti-leukemic activity of Dillenia indica L. fruit extract and quantification of betulinic acid by HPLC. Phytomedicine, 17(6):431-5.


Li L, Du Y, Kong X, et al. (2013). Lamin B1 Is a Novel Therapeutic Target of Betulinic Acid in Pancreatic Cancer. Clin Cancer Res, Epub July 9. doi: 10.1158/1078-0432.CCR-12-3630


Liu Y, Luo W. (2012). Betulinic acid induces Bax/Bak-independent cytochrome c release in human nasopharyngeal carcinoma cells. Molecules and cells, 33(5):517-524. doi: 10.1007/s10059-012-0022-5


Pisha E, Chai H, Lee I-S, et al. (1995). Discovery of betulinic acid as a selective inhibitor of human melanoma that functions by induction of apoptosis. Nature Medicine, 1:1046 – 1051. doi: 10.1038/nm1095-1046


Pyo JS, Roh SH, Kim DK, et al. (2009). Anti-Cancer Effect of Betulin on a Human Lung Cancer Cell Line: A Pharmacoproteomic Approach Using 2 D SDS PAGE Coupled with Nano-HPLC Tandem Mass Spectrometry. Planta Med, 75(2): 127-131. doi: 10.1055/s-0028-1088366


Reiner T, Parrondo R, de Las Pozas A, Palenzuela D, Perez-Stable C. (2013). Betulinic Acid Selectively Increases Protein Degradation and Enhances Prostate Cancer-Specific Apoptosis: Possible Role for Inhibition of Deubiquitinase Activity. PLoS One, 8(2):e56234. doi: 10.1371/journal.pone.0056234.


Rieber M & Strasberg-Rieber M. (1998). Induction of p53 without increase in p21WAF1 in betulinic acid-mediated cell death is preferential for human metastatic melanoma. DNA Cell Biol, 17(5):399–406. doi:10.1089/dna.1998.17.399.


Rzeski W, Stepulak A, Szymanski M, et al. (2009). Betulin Elicits Anti-Cancer Effects in Tumor Primary Cultures and Cell Lines In Vitro. Basic and Clinical Pharmacology and Toxicology, 105(6):425–432. doi: 10.1111/j.1742-7843.2009.00471.x


Selzer E, Pimentel E, Wacheck V, et al. (2000). Effects of Betulinic Acid Alone and in Combination with Irradiation in Human Melanoma Cells. Journal of Investigative Dermatology, 114:935–940; doi:10.1046/j.1523-1747.2000.00972.x


Sun S, Xu MZ, Poon RT, Day PJ, Luk JM. (2010). Circulating Lamin B1 (LMNB1) biomarker detects early stages of liver cancer in patients. J Proteome Res, 9(1):70-8. doi: 10.1021/pr9002118.


Tan YM, Yu R, Pezzuto JM. (2003). Betulinic Acid-induced Programmed Cell Death in Human Melanoma Cells Involves Mitogen-activated Protein Kinase Activation. Clin Cancer Res, 9:2866.


Thurnher D, Turhani D, Pelzmann M, et al. (2003). Betulinic acid: A new cytotoxic compound against malignant head and neck cancer cells. Head & Neck. 25(9):732–740. doi: 10.1002/hed.10231


Wang P, Li Q, Li K, Zhang X, et al. (2012). Betulinic acid exerts immunoregulation and anti-tumor effect on cervical carcinoma (U14) tumor-bearing mice. Pharmazie, 67(8):733-9.


Wick W, Grimmel C, Wagenknecht B, Dichgans J, Weller M. (1999). Betulinic Acid-Induced Apoptosis in Glioma Cells: A Sequential Requirement for New Protein Synthesis, Formation of Reactive Oxygen Species, and Caspase Processing. JPET, 289(3):1306-1312.


Zuco V, Supino R, Righetti SC, et al. (2002). Selective cytotoxicity of betulinic acid on tumor cell lines, but not on normal cells. Cancer Letters, 175(1): 17–25. doi:10.1016/S0304-3835(01)00718-2. PMID 11734332.

Akt, Anti-cancer, Anti-metastatic, anti-tumor, anti-tumor activity, apoptosis, BAX, Bcl-2, BCR, Breast cancer, Chapter 7 Isolates and Cancer Research, Chemo-sensitizer, Chemotherapy, G0/G1, G1, HL-60 and K562, induces apoptosis, inhibits proliferation, Leukemia, Liver cancer, MDR, NB4, p65, SMAD3, VEGF, VEGF

Berbamine

Cancer: Breast, leukemia, liver, neutropenia

Action: Anti-metastatic, chemo-sensitizer

Breast Cancer, Leukemia

Berbamine (BER), isolated from the Chinese herb Berberis amurensis and Berberis vulgaris (L.), selectively induces apoptosis in certain breast cancer and leukemia cell lines.

Studies have shown that berbamine suppresses the growth, migration and invasion in highly-metastatic human breast cancer cells by possibly inhibiting Akt and NF-kappaB signaling with their upstream target c-Met and downstream targets Bcl-2/Bax, osteopontin, VEGF, MMP-9 and MMP-2.

BER has synergistic effects with anti-cancer agents trichostatin A, celecoxib and carmofur on inhibiting the growth of MDA-MB-231 cells and reducing the ratio of Bcl-2/Bax and/or VEGF expressions in the cancer cells. These findings suggest that berbamine may have wide therapeutic and/or adjuvant therapeutic application in the treatment of human breast cancer and other cancers (Wang, 2009).

MDR, Leukemia stem cells

Previous studies have shown that berbamine selectively induces apoptosis of imatinib (IM)-resistant-Bcr/Abl-expressing leukemia cells from the K562 cell line and CML patients. Berbamine derivatives obtained by synthesis were found to have very high activity in vitro. Six of these exhibited consistent high anti-tumor activity for imatinib-resistant K562 leukemia cells. Their IC(50) values at 48h were 0.36-0.55 microM, whereas berbamine IC(50) value was 8.9 microM. Cell cycle analysis results showed that compound 3h could reduce G0/G1 cells. In particular, these compounds displayed potent inhibition of the cytoplasm-to-nucleus translocation of NF-kappaB p65 which plays a critical role in the survival of leukemia stem cells (Xie, 2009).

Liver Cancer, Leukemia

Meng et al. (2013) reported that berbamine and one of its derivatives, bbd24, potently suppressed liver cancer cell proliferation and induced cancer cell death by targeting Ca2+/calmodulin-dependent protein kinase II (CAMKII). Furthermore, berbamine inhibited the in vivo tumorigenicity of liver cancer cells in NOD/SCID mice and downregulated the self-renewal abilities of liver cancer-initiating cells. Berbamine inhibits proliferation and induces apoptosis of KU812 leukaemia cells by increasing Smad3 activity (Kapoor, 2012).

Chronic Myeloid Leukemia, Leukopenia

During imatinib therapy, many patients with chronic myeloid leukemia (CML) develop severe neutropenia, leading to treatment interruptions, and potentially compromising response to imatinib. Berbamine (a bisbenzylisoquinoline alkaloid) has been widely used in Asian countries for managing leukopenia associated with chemotherapy. With berbamine support, the time to achieve complete cytogenetic response was significantly shorter (median, 6.5 vs. 10 months, p = 0.007). There were no severe adverse events associated with berbamine treatment. In conclusion, the present study reveals the potential clinical value of berbamine in the treatment of CML with imatinib-induced neutropenia (Zhao et al., 2011).

References

Kapoor S. (2012). Emerging role of berbamine as an anti-cancer agent in systemic malignancies besides chronic myeloid leukemia. Zhejiang Univ Sci B, 13(9):761-2.


Meng Z, Li T, Ma X, et al. (2013). Berbamine Inhibits the Growth of Liver Cancer Cells and Cancer-Initiating Cells by Targeting Ca2+/Calmodulin-Dependent Protein Kinase II. Mol Cancer Ther.


Wang S, Liu Q, Zhang Y, et al. (2009). Suppression of growth, migration and invasion of highly-metastatic human breast cancer cells by berbamine and its molecular mechanisms of action. Mol Cancer, 8:81.


Xie J, Ma T, Gu Y, et al. (2009). Berbamine derivatives: A novel class of compounds for anti-leukemia activity. Eur J Med Chem, 44(8):3293-8. doi: 10.1016/j.ejmech.2009.02.018


Zhao Y, Tan Y, Wu G, et al. (2011). Berbamine overcomes imatinib-induced neutropenia and permits cytogenetic responses in Chinese patients with chronic-phase chronic myeloid leukemia. Int J Hematol, 94(2):156-62. doi: 10.1007/s12185-011-0887-7.

anti-oxidant, anti-tumor, anti-tumor activity, apoptosis, Bcl-2, Chapter 7 Isolates and Cancer Research, chemo-preventive, G2/M, hepato-protective, inflammation, Prostate cancer, S

β Solanine

Cancer: Liver, prostate

Action: Hepato-protective, apoptosis

The black nightshade (Solanum nigrum Linn.) has been widely used in Chinese traditional medicine as a remedy for the treatment of cancer. Solanum nigrum fruit extract could be used as an anti-oxidant and cancer chemo-preventive material. Solanum nigrum is an herbal plant that has been used as hepato-protective and anti-inflammation agent. The anti-tumor activity of solanine, a steroid alkaloid and active constituent isolated from the nightshade has been demonstrated in various cancer cell lines.

Observation of the cell-cycle showed that cells in the G2/M phases disappeared while the number of cells in the S phase increased significantly for treated groups. Western blot showed that solanine decreased the expression of Bcl-2 protein. Therefore, the target of solanine in inducing apoptosis in HepG2 cells seems to be mediated by the inhibition in the expression of Bcl-2 protein (Ji et al., 2008).

Apoptosis

HepG 2 cells were double stained with AO/EB, and morphological changes of the cells treated with solanine were observed using laser confocal scanning microscopy. Cells in treated groups showed typical signs of apoptosis. Staining with TMRE showed that solanine could lower membrane potential, and staining with Fluo-3/AM showed that solanine could increase the concentration of calcium in tumor cells; those double stained with TMRE and Fluo-3/AM showed that solanine could increase the concentration of calcium in the cells at the same time as it lowered the membrane potential of mitochondria.

Sola was found to open up the PT channels in the membrane by lowering the membrane potential, leading to calcium being transported down its concentration gradient, which in turn led to the rise of the concentration of calcium in the cell, turning on the mechanism for apoptosis (Gao et al., 2006).

Hepato-protective

Solanine (SNE) also has hepato-protective activity against CCl4-induced hepatic damage in rats. The results of the study suggest that Solanum nigrum protects liver against the CCl4-induced oxidative damage in rats, and this hepato-protective effect might be contributed to its modulation on detoxification enzymes and its anti-oxidant and free radical scavenger effects. Oral administration of SNE significantly reduces Thioacetamide -induced hepatic fibrosis in mice, probably through the reduction of transforming growth factor-β1 secretion. It also protects against hepatitis B virus infection B10 (Kaushik et al., 2009).

Prostate Cancer

Solanine has an anti-prostate cancer effect by inhibiting PC-3 cell proliferation, arresting the S phase, inducing cell apoptosis, up-regulating the protein expression of I(kappa)B(alpha) and down-regulating that of Bcl-2. Solanine suppressed the growth of PC-3 cells in a dose- and time-dependent manner in vitro, with significant differences among different concentration and time groups (P < 0.05).

The cycle of the PC-3 cells was arrested in the S phase (P < 0.05), with a significantly higher rate of apoptosis in the treated groups than in the controls (P < 0.05). The protein expression of I(kappa)B(alpha) was obviously up-regulated and that of Bcl-2 down-regulated in all the solanine concentration groups (Zhang & Shi, 2011).

References

Gao SY, Wang QJ, Ji YB. (2006). Effect of solanine on the membrane potential of mitochondria in HepG2 cells and [Ca2+] i in the cells. World J Gastroenterol, 12(21):3359-3367


Ji YB,Gao SY, Ji CF, Zou X. (2008). Induction of apoptosis in HepG2 cells by solanine and Bcl-2 protein. Journal of Ethnopharmacology, 115(2):194-202. doi:10.1016/j.jep.2007.09.023


Kaushik D, Jogpal V, Kaushik P, Lal S et al. (2009). Evaluation of activities of Solanum nigrum fruit extract. Archives of Applied Science Research, 1(1):43-50


Zhang J, Shi GW. (2011). Inhibitory effect of solanine on prostate cancer cell line PC-3 in vitro. Zhonghua Nan Ke Xue, 17(3):284-7.