Category Archives: anti-oxidative

Rosmarinic Acid

Cancer: Leukemia

Action: Anti-oxidative, MDR

Leukemia

Because tumor necrosis factor-alpha (TNF-alpha) is well known to induce inflammatory responses, its clinical use is limited in cancer treatment. Rosmarinic acid (RA), a naturally occurring polyphenol flavonoid, has been reported to inhibit TNF-alpha-induced NF-kappaB activation in human dermal fibroblasts. Investigation found that RA treatment significantly sensitizes TNF-alpha-induced apoptosis in human leukemia U937 cells through the suppression of nuclear transcription factor-kappaB (NF-kappaB) and reactive oxygen species (ROS). This inhibition was correlated with suppression of NF-kappaB-dependent anti-apoptotic proteins (IAP-1, IAP-2, and XIAP). RA treatment also normalized TNF-alpha-induced ROS generation. Additionally, ectopic Bcl-2 expressing U937 reversed combined treatment-induced cell death, cytochrome c release into cytosol, and collapse of mitochondrial potential.

Results demonstrated that RA inhibits TNF-alpha-induced ROS generation and NF-kappaB activation, and enhances TNF-alpha-induced apoptosis (Moon, Kim, Lee, Choi, & Kim, 2010).

MDR

The intracellular accumulation of adriamycin, rhodamine123 (Rh123), and the expression of P-glycoprotein (P-gp) were assayed by flow cytometry. The influence of RA on the transcription of MDR1 gene was determined by reverse transcription-polymerase chain reaction. The results showed that RA could reverse the MDR of SGC7901/Adr cells, increase the intracellular accumulation of Adr and Rh123, and decrease the transcription of MDR1 gene and the expression of P-gp in SGC7901/Adr cells (Li et al., 2013).

Anti-cancer

Rosmarinic acid (RA), one of the major components of polyphenol, possesses attractive remedial features. Supplementation with RA significantly reduced the formation of aberrant crypt foci (ACF) and ACF multiplicity in 1,2-dimethylhydrazine (DMH) treated rats. Moreover RA supplementation prevented the alterations in circulatory anti-oxidant enzymes and colonic bacterial enzymes activities. Overall, results showed that all three doses of RA inhibited carcinogenesis, though the effect of the intermediary dose of 5 mg/kg b.w. was more pronounced (Karthikkumar et al., 2012).

References

Karthikkumar V, Sivagami G, Vinothkumar R, Rajkumar D, Nalini N. (2012). Modulatory efficacy of rosmarinic acid on premalignant lesions and anti-oxidant status in 1,2-dimethylhydrazine induced rat colon carcinogenesis. Environ Toxicol Pharmacol, 34(3):949-58. doi: 10.1016/j.etap.2012.07.014.


Li FR, Fu YY, Jiang DH, et al. (2013). Reversal effect of rosmarinic acid on Multi-drug resistance in SGC7901/Adr cell. J Asian Nat Prod Res, 15(3):276-85. doi: 10.1080/10286020.2012.762910.


Moon DO, Kim MO, Lee JD, Choi YH, Kim GY. (2010). Rosmarinic acid sensitizes cell death through suppression of TNF-alpha-induced NF-kappaB activation and ROS generation in human leukemia U937 cells. Cancer Letters, 288(2), 183-191. doi: 10.1016/j.canlet.2009.06.033.

Piceatannol

Cancer: Esophageal, colorectal, breast

Action: Anti-inflammatory, anti-oxidative

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

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

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

Esophageal Cancer

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

Colorectal

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

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

Anti-inflammatory

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

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

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

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

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

Breast Cancer

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

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

References

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


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


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


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


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

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.

Campesterol

Cancer: Breast, prostate

Action: Anti-angiogenic, anti-oxidative

Anti-angiogenic

Campesterol, a plant sterol in nature, is known to have cholesterol-lowering and anti-carcinogenic effects. Since angiogenesis is essential for cancer, it was surmised that an anti-angiogenic effect may be involved in the anti-cancer action of this compound. This study investigated the effect of campesterol on basic fibroblast growth factor (bFGF)-induced angiogenesis in vitro in human umbilical vein endothelial cells (HUVECs) and an in vivo chorioallantoic membrane (CAM) model.

Campesterol, isolated from an ethylacetate fraction of Chrysanthemum coronarium (L.), showed a weak cytotoxicity in non-proliferating HUVECs. Within the non-cytotoxic concentration range, campesterol significantly inhibited the bFGF-induced proliferation and tube formation of HUVECs in a concentration-dependent manner, without affecting the motility of HUVECs. Furthermore, campesterol effectively disrupted the bFGF-induced neovascularization in chick chorioallantoic membranes (CAM) in vivo.

Taken together, these results support a potential anti-angiogenic action of campesterol via an inhibition of endothelial cell proliferation and capillary differentiation (Choi et al., 2007).

Metastatic Breast Cancer

Porphyra dentata, an edible red macroalgae, is used as a folk medicine in Asia. The in vitro and in vivo protective effects of a sterol fraction from P. dentata against breast cancer, linked to tumor-induced myeloid derived-suppressor cells (MDSCs), was investigated.

A sterol fraction containing cholesterol, β-sitosterol, and campesterol was prepared by solvent fractionation of methanol extract of P. dentata   in silica gel column chromatography. This sterol fraction in vitro significantly inhibited cell growth and induced apoptosis in 4T1 metastatic breast cancer cells. Intraperitoneal injection of this sterol fraction at 10 and 25  mg/kg body weight into 4T1 cell-implanted tumor BALB/c mice significantly inhibited the growth of tumor nodules and increased the survival rate of mice.

Two likely mechanisms for this effect can be suggested. First, the sample might cause the apoptosis of 4T1 cells. The other possible mechanism is that the sample may down-regulate the suppressive activity of MDSCs by affecting their ROS accumulation and arginase activity. This inhibition would be consistent with the use of Porphyra dentata as a folk medicine to treat inflammatory disorders and also for breast cancer (Kazlowska, Lin, Chang & Tsai, 2013).

Prostate Cancer

In the in vitro studies, both beta-sitosterol and campesterol inhibited the growth of human prostate cancer (PC-3) cells by 70% and 14%, respectively, while cholesterol supplementation increased the growth by 18% when compared with controls. Phytosterols (PS) mixture inhibited the invasion of PC-3 cells into Matrigel-coated membranes by 78% while cholesterol increased it by 43% as compared with the cells in the control media. PS supplementation reduced the binding of PC-3 cells to laminin by 15-38% and fibronectin by 23% while cholesterol increased binding to type IV collagen by 36%. It was concluded that PS indirectly (in vivo as a dietary supplement) and directly (in tissue culture media) inhibited the growth and metastasis of PC-3 cells (Awad et al., 2001).

References

Awad AB, Fink CS, Williams H, Kim U. (2001). In vitro and in vivo (SCID mice) effects of phytosterols on the growth and dissemination of human prostate cancer PC-3 cells. Eur J Cancer Prev, 10(6):507-13.


Choi JM, Lee EO, Lee HJ, et al. (2007). Identification of campesterol from chrysanthemum coronarium l. and its anti-angiogenic activities. Phytotherapy Research, 21(10), 954-959.


Kazlowska K, Lin HTV, Chang SH, Tsai GJ. (2013). In vitro and in vivo anti-cancer effects of sterol fraction from red algae porphyra. Evidence-Based Complementary and Alternative Medicine, 2013(2013), 493869. http://dx.doi.org/10.1155/2013/493869.

Berberine

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

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

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

Anti-inflammatory

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

Angiogenesis, Chemo-enhancing

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

Cell-cycle Arrest

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

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

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

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

Anti-metastatic

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

Hepatoma, Leukaemia

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

Leukemia

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

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

Prostate Cancer

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

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

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

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

Breast Cancer

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

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

Breast Cancer Metastasis

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

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

Melanoma

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

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

Cell-cycle Arrest, Squamous-cell Carcinoma

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

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

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

Cervical Cancer, Radio-sensitizer

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

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

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

Anti-oxidative; Breast, Liver and Colon Cancer

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

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

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

Source:

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

References

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β Sitosterol

Cancer: Breast, multiple myeloma

Action: Anti-oxidative

Breast Cancer

While many factors are involved in the etiology of cancer, it has been clearly established that diet significantly impacts one's risk for this disease. More recently, specific food components have been identified which are uniquely beneficial in mitigating the risk of specific cancer subtypes. Plant sterols are well known for their effects on blood cholesterol levels, however research into their potential role in mitigating cancer risk remains in its infancy. The cholesterol modulating actions of plant sterols may overlap with their anti-cancer actions.

Breast cancer is the most common malignancy affecting women and there remains a need for effective adjuvant therapies for this disease, for which plant sterols may play a distinctive role (Grattan, 2013).

Porphyra dentata, an edible red macroalgae, is used as a folk medicine in Asia. The in vitro and in vivo protective effects of a sterol fraction from P. dentata against breast cancer, linked to tumor-induced myeloid derived-suppressor cells (MDSCs), was investigated.

A sterol fraction containing cholesterol, β-sitosterol, and campesterol was prepared by solvent fractionation of methanol extract of P. dentata    in silica gel column chromatography. This sterol fraction in vitro significantly inhibited cell growth and induced apoptosis in 4T1 cancer cells.

The sterol fraction from P. dentata showed potential for protecting an organism from 4T1 cell-based tumor genesis. The anti-cancer effects potentially are a result of the presence of beta-sitosterol and campesterol. This sterol-containing fraction reduced tumorgenesis and increased the survival rate of 4T1-engrafted mice. This inhibition would be consistent with the use of Porphyra dentata as a folk medicine to treat inflammatory disorders and also for breast cancer (Kazlowska et al., 2013).

The role of reactive oxygen species (ROS) in association with AMP-activated protein kinase (AMPK) and c-Jun N-terminal kinase (JNK) pathways was demonstrated in beta-sitosterol-treated multiple myeloma U266 cells. Beta-sitosterol exerted cytotoxicity, increased sub-G1 apoptotic population and activated caspase-9 and -3, cleaved poly (ADP-ribose) polymerase (PARP) followed by decrease in mitochondrial potential in U266 cells. Beta-sitosterol promoted ROS production, activated AMPK, acetyl-CoA carboxylase (ACC) and JNK in U266 cells. Also, beta-sitosterol attenuated the phosphorylation of AKT, mammalian target of rapamycin and S6K, and the expression of cyclooxygenase-2 and VEGF in U266 cells (Sook et al., 2013).

Cancer: Breast, skin epidermoid carcinoma, lung epithelial carcinoma

Action: Promotes apoptosis, antioxidant activity

Among many cancers, breast cancer in females and lung cancer in males are the most frequently diagnosed cancers and the leading cause of cancer death for each sex in both economically developed and developing countries [1]. Lung cancer accounted for 13% of the total cases and 18% of the deaths due to cancer occurred in 2008 [1]. Skin cancer is the major cutaneous malignancy and about 76,250 people are estimated to be diagnosed for skin cancer in 2013 [2]. Incidence rate for melanoma has been rising from past three decades. Breast cancer is by far the most frequent cancer among women with an estimated 23% of all cancers and is the most frequent cause of cancer death in women [1].

The use of natural, synthetic or biological agents to prevent, reverse or suppress the growth and progression of cancer is referred as chemoprevention of cancer [3]. It is one of the most promising strategies for cancer control, and is accomplished by various means including chemoprevention by phytochemicals from vegetables, fruits, spices, teas, herbs and medicinal plants thus making it as one of the most feasible means of cancer control [4]. Phytochemicals are secondary plant metabolites and have been used for centuries throughout the world in traditional cures and herbal remedies, and as ayurvedic and homeopathic medicines in India. More recently, there has been a considerable interest in secondary plant metabolites because of their potential preventative effects on chronic diseases including cancer.

Many studies have demonstrated that phytochemicals in common fruits and vegetables can have complementary and overlapping mechanisms of action, including antioxidant activity, scavenging free radicals and regulation of gene expression, including oncogenes and tumor suppressor genes, in cell proliferation and cell differentiation; induction of cell-cycle arrest and apoptosis; modulation of enzyme activities in detoxification, oxidation and reduction; stimulation of the immune system; regulation of hormone metabolism; and antibacterial and antiviral effects [5-7]. Phytosterols (PS) are triterpenes that are important structural components of plant membranes. More than 200 different types of phytosterols have been reported in plant species. The richest sources of phytosterols are vegetable oils, nuts, cereal products, fruits and berries [8]. Structural resemblance of PS with cholesterol enables them to displace low-density lipoprotein (LDL) cholesterol in the human intestine [9]. Protective effects of PS against cardiovascular diseases (CVD), colon and breast cancer developments have been widely documented. The most common dietary phytosterols are β-sitosterol, campesterol and stigmasterol. Among these, the most abundant phytosterol is β-sitosterol. Studies have shown that β-sitosterol exhibits anti-inflammatory, angiogenic and immune-modulating properties [10]. β-sitosterol is reported to activate Fas signaling in breast cancer cells [11], and induce cell cycle arrest and apoptotic cell death in prostate cancer cells [12,13].

Herein, we evaluated the efficacy of β-sitosterol on three different cancer cell lines including human skin epidermoid carcinoma cell line (A431), human lung epithelial carcinoma cell line (A549) and human breast adenocarcinoma cell line (MDA-MB-231). It was observed that as compared to A431 and A549 cells, β-sitosterol showed prominent growth inhibitory and pro-apoptotic activity in MDA-MB-231 cells. Further, study provides valuable insight into the chemopreventive efficacy and associated molecular alterations of β-sitosterol in breast cancer cells in culture.

The current study shows that β-Sitosterol (ST), a dietary phytosterol has stronger anticancer activity against breast cancer cells compared to lung and skin cancer cells which may be attributed to the differential expression of genes including hormones, receptors and tissue specific proteins. Along with anti-proliferative and growth inhibitory effect, ST induced G0/G1 cell cycle arrest via modulation of cell cycle regulators CDK4, cyclin D1, p21/Cip1and p27/Kip1 breast cancer cells. Further ST caused cell death involves the induction of apoptosis in breast cancer cells via mitochondrial membrane depolarization and increase in Bax/Bcl-2 ratio. This study provides valuable insight into the chemopreventive efficacy and associated molecular alterations of ST in breast cancer cells. However, further studies are needed to understand and assess the potential clinical utility of ST as a chemopreventive agent against breast cancer.

References

Grattan BJ Jr. (2013). Plant sterols as anti-cancer nutrients: evidence for their role in breast cancer. Nutrients, 5(2):359-87. doi: 10.3390/nu5020359.


Kazlowska K, Lin HTV, Chang SH, Tsai GJ. Evidence-Based Complementary and Alternative Medicine. (2013). In vitro and in vivo anti-cancer effects of sterol fraction from red algae porphyra. Evidence-Based Complementary and Alternative Medicine, 2013(2013), 493869. http://dx.doi.org/10.1155/2013/493869.


Sook SH, Lee HJ, Kim JH, et al. (2013). Reactive Oxygen Species-Mediated Activation of AMP-Activated Protein Kinase and c-Jun N-terminal Kinase Plays a Critical Role in Beta-Sitosterol-Induced Apoptosis in Multiple Myeloma U266 cells. Phytother Res. doi: 10.1002/ptr.4999.

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Ellagic Acid

Cancer:
Pancreatic, prostate, ovarian, breast, bladder, lymphoma, oral., melanoma

Action: Anti-cancer, induces apoptosis, promoted ROS and Ca2+ productions

Ellagic acid (EA) is a polyphenol compound widely found in fruits such as berries, walnuts, pecans, pomegranate, cranberries, and longan. It is well known to have a free radical scavenging activity and has been approved in Japan as an 'existing food additive' for anti-oxidative purposes (HHLW, 1996). In vitro evidence revealed that 100µM EA represented little toxic effect on human normal cells (Losso et al., 2004; Larrosa et al., 2006). A subchronic toxicity study further demonstrated that orally feeding EA (9.4, 19.1, 39.1g/kg b.w., resp.) could not induce mortality or treatment-related clinical signs throughout the experimental period on F344 rats (Tasaki et al., 2008), indicating the low toxicity of EA to mammalians. Furthermore, EA exhibits potent anti-cancer and anti-carcinogenesis activities towards breast, colorectal., oral., prostate (Losso et al., 2004; Larrosa et al., 2006; Malik et al., 2011), pancreatic (Edderkaoui et al., 2008), bladder (Li et al., 2005), neuroblastoma (Fjaeraa et al., 2009), melanoma (Kim et al., 2009), and lymphoma cells (Mishra et al., 2011).

Pancreatic Cancer

Edderkaoui et al. (2008) show that ellagic acid, a polyphenolic compound in fruits and berries, at concentrations 10 to 50 mmol/L stimulates apoptosis in human pancreatic adenocarcinoma cells. Ellagic acid stimulates the mitochondrial pathway of apoptosis associated with mitochondrial depolarization, cytochrome C release, and the downstream caspase activation. Ellagic acid does not directly affect mitochondria. Ellagic acid dose-dependently decreased NF-kappa B binding activity.

Furthermore, inhibition of NF-kappa B activity using IkB wild type plasmid prevented the effect of ellagic acid on apoptosis.

Pancreatic Cancer (PANC-1) cells were injected subcutaneously into Balb c nude mice, and tumor-bearing mice were treated with ellagic acid (EA). Treatment of PANC-1 xenografted mice with EA resulted in significant inhibition in tumor growth which was associated with suppression of cell proliferation and caspase-3 activation, and induction of PARP cleavage. EA also reversed epithelial to mesenchymal transition by up-regulating E-cadherin and inhibiting the expression of Snail, MMP-2 and MMP-9.

These data suggest that EA can inhibit pancreatic cancer growth, angiogenesis and metastasis by suppressing Akt, Shh and Notch pathways. In view of the fact that EA could effectively inhibit human pancreatic cancer growth by suppressing Akt, Shh and Notch pathways, our findings suggest that the use of EA would be beneficial for the management of pancreatic cancer (Zhao et al., 2013).

Ovarian Cancer

Ovarian carcinoma ES-2 and PA-1 cells were treated with EA (10~100  µ M) and assessed for viability, cell-cycle, apoptosis, anoikis, autophagy, and chemosensitivity to doxorubicin and their molecular mechanisms. EA inhibited cell proliferation in a dose- and time-dependent manner by arresting both cell lines at the G1 phase of the cell-cycle, which were from elevating p53 and Cip1/p21 and decreasing cyclin D1 and E levels. EA also induced caspase-3-mediated apoptosis by increasing the Bax :  Bcl-2 ratio and restored anoikis in both cell lines.

The enhancement of apoptosis and/or inhibition of autophagy in these cells by EA assisted the chemotherapy efficacy. The results indicated that EA is a potential novel chemoprevention and treatment assistant agent for human ovarian carcinoma Chung et al., 2013).

Prostate Cancer; AR+

In the present study, Pitchakarn et al. (2013) investigated anti-invasive effects of ellagic acid (EA) in androgen-independent human (PC-3) and rat (PLS10) prostate cancer cell lines in vitro. The results indicated that non-toxic concentrations of EA significantly inhibited the motility and invasion of cells examined in migration and invasion assays. They found that EA significantly reduced proteolytic activity of collagenase/gelatinase secreted from the PLS-10 cell line. Collagenase IV activity was also concentration-dependently inhibited by EA. These results demonstrated that EA has an ability to inhibit invasive potential of prostate cancer cells through action on protease activity.

Breast Cancer

The role of estrogen (E2) in regulation of cell proliferation and breast carcinogenesis is well-known. Recent reports have associated several miRNAs with estrogen receptors in breast cancers. Investigation of the regulatory role of miRNAs is critical for understanding the effect of E2 in human breast cancer, as well as developing strategies for cancer chemoprevention.

In this study Munagala et al. (2013) used the well-established ACI rat model that develops mammary tumors upon E2 exposure and identified a 'signature' of 33 significantly modulated miRNAs during the process of mammary tumorigenesis. Several of these miRNAs were altered as early as 3 weeks after initial E2 treatment and their modulation persisted throughout the mammary carcinogenesis process, suggesting that these molecular changes are early events. This is the first systematic study examining the changes in miRNA expression associated with E2 treatment in ACI rats as early as 3weeks until tumor time point. The effect of a chemo-preventive agent, ellagic acid in reversing miRNAs modulated during E2-mediated mammary tumorigenesis is also established. These observations provide mechanistic insights into the new molecular events behind the chemo-preventive action of ellagic acid and treatment of breast cancer.

Bladder Cancer

To investigate the effects of ellagic acid on the growth inhibition of TSGH8301 human bladder cancer cells in vitro, cells were incubated with various doses of ellagic acid for different time periods. Results indicated that ellagic acid induced morphological changes, decreased the percentage of viable cells through the induction of G0/G1 phase arrest and apoptosis, and also showed that ellagic acid promoted ROS and Ca2+ productions and decreased the level of ΔΨm and promoted activities of caspase-9 and -3.

On the basis of these observations, Ho et al (2013) suggest that ellagic acid induced cytotoxic effects for causing a decrease in the percentage of viable cells via G0/G1 phase arrest and induction of apoptosis in TSGH8301 cells.

Lymphoma

Protein Kinase C (PKC) isozymes are key components involved in cell proliferation and their over activation leads to abnormal tumor growth. PKC follows signaling pathway by activation of downstream gene NF-kB and early transcription factor c-Myc. Over activation of NF-kB and c-Myc gene are also linked with unregulated proliferation of cancer cells.

Therefore any agent which can inhibit the activation of Protein kinase C, NF-kB and c-Myc may be useful in reducing cancer progression. The role of ellagic acid was tested in regulation of tumor suppressor gene Transforming growth factor-β1 (TGF-β1). DL mice were treated with three different doses (40, 60 and 80 mg/kg body weight) of ellagic acid. Ascites cells of mice were used for the experiments. Ellagic acid administration to DL mice decreased oxidative stress by reducing lipid peroxidation.

The anti-carcinogenic action of ellagic acid was also confirmed by up-regulation of TGF-β1 and down-regulation of c-Myc. Lymphoma prevention by ellagic acid is further supported by decrease in cell proliferation, cell viability, ascites fluid accumulation and increase in life span of DL mice. All these findings suggest that ellagic acid prevents the cancer progression by down- regulation of PKC signaling pathway leading to cell proliferation (Mishra et al., 2013).

References

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