Category Archives: PARP

Zerumbone

Cancer:
Colorectal, renal carcinoma, glioblastoma, ovarian and cervical

Action: CSCs, anti-inflammatory

Zerumbone is isolated from Zingiber zerumbet [(L.) Roscoe ex Sm.].

Colorectal Cancer

Numerous agents from 'mother nature' (also called nutraceuticals) that have potential to both prevent and treat CRC have been identified. The most significant discoveries relate to compounds such as cardamonin, celastrol, curcumin, deguelin, diosgenin, thymoquinone, tocotrienol, ursolic acid, and zerumbone. Unlike pharmaceutical drugs, these agents modulate multiple targets, including transcription factors, growth factors, tumor cell survival factors, inflammatory pathways, and invasion and angiogenesis linked closely to CRC. We describe the potential of these dietary agents to suppress the growth of human CRC cells in culture and to inhibit tumor growth in animal models (Aggarwal et al., 2013).

Cancer Stem Cells (CSCs)

Cancer stem cells (CSCs) are a major cause of cancer treatment failure, relapse, and drug resistance and are known to be responsible for cancer cell invasion and metastasis. The Sonic hedgehog (Shh) signaling pathway is crucial to embryonic development. Intriguingly, the aberrant activation of the Shh pathway plays a critical role in developing CSCs and leads to angiogenesis, migration, invasion, and metastasis. Natural compounds and chemical structure modified derivatives from complementary and alternative medicine have received increasing attention as cancer chemo-preventives, and their anti-tumor effects have been demonstrated both in vitro and in vivo.

Compounds cyclopamine, curcumin, epigallocatechin-3-gallate, genistein, resveratrol, zerumbone, norcantharidin, and arsenic trioxide, with a focus on Shh signaling blockade, were reviewed by Huang et al. (2013) and given that Shh signaling antagonism has been clinically proven as an effective strategy against CSCs, this review may be exploitable for the development of novel anti-cancer agents from complementary and alternative medicine.

Renal Carcinoma

Sun et al. (2013) reported that zerumbone, a monosesquiterpine, shows anti-cancer effects on human RCC cells via induction of apoptosis in vitro. Human renal clear cell carcinoma 786-0 and 769-P cell lines were used as the model system. Exposure of RCC cells to zerumbone resulted in cell viability inhibition, accompanied by DNA fragmentation and increased apoptotic index. Mechanically, treatment of RCC cells with zerumbone activated caspase-3 and caspase-9 finally led to cleavage of PARR.

Taken together, our studies provided the first evidence that zerumbone imparted strong inhibitory and apoptotic effects on human RCC cells. The zerumbone-induced apoptosis might be related to the activation of the caspase cascade and deregulation of the Gli-1/Bcl-2 pathway. Our results suggest that zerumbone merit further investigation as an apoptosis inducer as well as a novel RCC chemotherapeutic agent in the clinical setting.

Glioblastoma

Zerumbone (10~50 µM) induced death of human glioblastoma multiforme (GBM8401) cells in a dose-dependent manner. Flow cytometry studies showed that zerumbone increased the percentage of apoptotic GBM cells. Zerumbone also caused caspase-3 activation and poly (ADP-ribose) polymerase (PARP) production. N-benzyloxycarbonyl -Val-Ala-Asp- fluoromethylketone (zVAD-fmk), a broad-spectrum caspase inhibitor, hindered zerumbone-induced cell death. Moreover, transfection of GBM8401 cells with WT IKKα reduced the zerumbone-induced decrease in Akt and FOXO1 phosphorylation. However, transfection with WT Akt decreased FOXO1, but not IKKα, phosphorylation.

The results suggest that inactivation of IKKα, followed by Akt and FOXO1 phosphorylation and caspase-3 activation, contributes to zerumbone-induced GBM cell apoptosis (Weng et al., 2012).

Ovarian and Cervical Cancer

A study by Abdelwahab et al., (2012) was designed to investigate the role of IL-6 and IL6 receptors in the cytotoxic effects of zerumbone in ovarian and cervical cancer cell lines (Caov-3 and HeLa, respectively). Exposure of both cancer cells to zerumbone or cisplatin demonstrated growth inhibition in a dose-dependent manner as determined by the MTT reduction assay. The studies conducted seem to suggest that zerumbone induces cell death by stimulating apoptosis better than cisplatin, based on the significantly higher percentage of apoptotic cells in zerumbone's treated cancer cells as compared to cisplatin. In addition, zerumbone and cisplatin arrest cancer cells at G2/M phase as analyzed by flow cytometry. These results indicated that zerumbone significantly decreased the levels of IL-6 secreted by both cancer cells.

This study concludes that the compound, zerumbone, inhibits cancer cell growth through the induction of apoptosis, arrests cell-cycle at G2/M phase and inhibits the secretion levels of IL-6 in both cancer cells.

References

Abdelwahab SI, Abdul AB, Zain ZN, Hadi AH. (2012). Zerumbone inhibits interleukin-6 and induces apoptosis and cell-cycle arrest in ovarian and cervical cancer cells. Int Immunopharmacol,12(4):594-602. doi: 10.1016/j.intimp.2012.01.014.


Aggarwal B, Prasad S, Sung B, Krishnan S, Guha S. (2013). Prevention and Treatment of Colorectal Cancer by Natural Agents From Mother Nature. Curr Colorectal Cancer Rep, 9(1):37-56.


Huang YC, Chao KS, Liao HF, Chen YJ. (2013). Targeting sonic hedgehog signaling by compounds and derivatives from natural products. Evid Based Complement Alternat Med, 2013:748587. doi: 10.1155/2013/748587.


Sun Y, Sheng Q, Cheng Y, et al. (2013). Zerumbone induces apoptosis in human renal cell carcinoma via Gli-1/Bcl-2 pathway. Pharmazie, 68(2):141-5.


Weng HY, Hsu MJ, Wang CC, et al. (2012). Zerumbone suppresses IKK α , Akt, and FOXO1 activation, resulting in apoptosis of GBM 8401 cells. J Biomed Sci, 19:86. doi: 10.1186/1423-0127-19-86.

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.

Teng Long Bu Zhong Tang

Cancer: Colon

Action: Induces apoptosis, inhibits angiogenesis

CT26 colon carcinoma was established in BALB/c mice and treated with Teng Long Bu Zhong Tang (TLBZT), 5-Fu, or TLBZT plus 5-Fu. The tumor volumes were observed. TLBZT significantly inhibited CT26 colon carcinoma growth. TLBZT elicited apoptosis in CT26 colon carcinoma, accompanied by Caspase-3, 8, and 9 activation and PARP cleavage, and down-regulation of XIAP and Survivin. TLBZT also induced cell senescence in CT26 colon carcinoma, with concomitant up-regulation of p16 and p21 and down-regulation of RB phosphorylation.

In addition, angiogenesis and VEGF expression in CT26 colon carcinoma was significantly inhibited by TLBZT treatment. TLBZT exhibited significant anti-cancer effect, and enhanced the effects of 5-Fu in CT26 colon carcinoma, which may correlate with induction of apoptosis and cell senescence, and angiogenesis inhibition (Deng et al., 2013).

Reference

Deng S, Hu B, An HM, et al. (2013). Teng-Long-Bu-Zhong-Tang, a Chinese herbal formula, enhances anti-cancer effects of 5 – Fluorouracil in CT26 colon carcinoma. BMC Complement Altern Med, 13:128. doi: 10.1186/1472-6882-13-128.

Subamolide A

Cancer: Lung, urothelial carcinoma

Action: Increases cellular reactive oxygen species (ROS) production, decreases glutathione level

Lung Cancer

Subamolide A is isolated from Cinnamomum subavenium (Miq.). The anti-cancer effects of subamolide A (Sub-A) were investigated on human nonsmall cell lung cancer cell lines A549 and NCI-H460. Treatment of cancer cells with Sub-A resulted in decreased cell viability of both lung cancer cell lines. Sub-A induced lung cancer cell death by triggering mitotic catastrophe with apoptosis. It triggered oxidant stress, indicated by increased cellular reactive oxygen species (ROS) production and decreased glutathione level.

Therefore, Sub-A may be a novel anti-cancer agent for the treatment of non-small-cell lung cancer. Human lung cancer cells A549 and NCI-H460 are highly sensitive to Sub-A-induced mitotic catastrophe and apoptosis, mainly via ROS elevation that induces ATM and ATF3 activation, subsequently leading to p53-mediated cell death. Sub-A also causes cell growth inhibition in an in vivo xenograft model. The elucidated molecular bases and processes may provide a new strategy for developing more effective chemotherapeutic regimens for lung cancer treatment (Hung et al., 2013).

Urothelial Carcinoma

A study by Liu et al. (2011) demonstrated that subamolide A triggered the mitochondria-dependent apoptotic pathways and p53 and ERK1/2 activation in the human urothelial carcinoma cell line NTUB1. In addition, subamolide A synergistically enhanced cytotoxic effect of CDDP and Gem in NTUB1. These data suggested that subamolide A exhibited a potent anti-proliferation activity.

Subamolide A selectively induced apoptosis in two cancerous human urothelial carcinoma cell lines (NTUB1 and T24) in comparison with normal immortalized uroepithelial cells (SV-HUC-1). Subamolide A reduced mitochondrial membrane potential (Δψm) and caused apoptosis of NTUB1 cells. Subamolide A increased Bax/Bcl-2 ratios, the amount of cytochrome c released from the mitochondria, caspase-3 and PARP cleavage, activated p53 and ERK1/2 and ultimately led to apoptosis in NTUB1 cells. Furthermore, a higher dose (10µM) of subamolide A synergistically enhanced the cytotoxicity of cisplatin and gemcitabine in NTUB1 cells.

References

Hung JY, Wen CW, Hsu YL, et al. (2013). Subamolide A Induces Mitotic Catastrophe Accompanied by Apoptosis in Human Lung Cancer Cells. Evidence-Based Complementary and Alternative Medicine, 2013: 828143. doi:10.1155/2013/828143.


Liu CH, Chen CY, Huang AM, Li JH. (2011) Subamolide A, a component isolated from Cinnamomum subavenium, induces apoptosis mediated by mitochondria-dependent, p53 and ERK1/2 pathways in human urothelial carcinoma cell line NTUB1. J Ethnopharmacol,137(1):503-11. doi: 10.1016/j.jep.2011.06.001.

Saikosaponin

Cancers:
Cervical, colon, liver, lung, ovarian, liver, breast, hepatocellular

Action: Anti-angiogenic, anti-metastatic, chemo-sensitizer, pro-oxidative, cell-cycle arrest

T cell-mediated autoimmune, induces apoptosis, immune regulating, radio-sensitizer

Induces Apoptosis

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

Annexin V immunofluorescence detection, DNA fragmentation assays and FACScan analysis of propidium iodide-staining cells showed that gentiopicroside, baicalein, and geniposide had little effect, whereas alisol B acetate and saikosaponin-d profoundly induced apoptosis in Hep3B cells. Alisol B acetate, but not saikosaponin-d, induced G2/M arrest of the cell-cycle as well as a significant increase in caspase-3 activity. Interestingly, baicalein by itself induced an increase in H(2)O(2) generation and the subsequent NF-kappaB activation; furthermore, it effectively inhibited the transforming growth factor-beta(1) (TGF-beta(1))-induced caspase-3 activation and cell apoptosis.

Results suggest that alisol B acetate and saikosaponin-d induced cell apoptosis through the caspase-3-dependent and -independent pathways, respectively. Instead of inducing apoptosis, baicalein inhibits TGF-beta(1)-induced apoptosis via increase in cellular H(2)O(2) formation and NF-kappaB activation in human hepatoma Hep3B cells (Chou, Pan, Teng & Guh, 2003).

Breast

Saikosaponin-A treatment of MDA-MB-231 for 3 hours and of MCF-7 cells for 2 hours, respectively, caused an obvious increase in the sub G1 population of cell-cycles.

Apoptosis in MDA-MB-231 cells was independent of the p53/p21 pathway mechanism and was accompanied by an increased ratio of Bax to Bcl-2 and c-myc levels and activation of caspase-3. In contrast, apoptosis of MCF-7 cells may have been initiated by the Bcl-2 family of proteins and involved p53/p21 dependent pathway mechanism, and was accompanied by an increased level of c-myc protein. The apoptosis of both MDA-MB-231 and MCF-7 cells showed a difference worthy of further research (Chen, Chang, Chung, & Chen, 2003).

Hepatocellular Carcinoma

The signaling pathway mediating induction of p15(INK4b) and p16(INK4a) during HepG2 growth inhibition triggered by the phorbol ester tumor promoter TPA (12-O-tetradecanoylphorbol 13-acetate) and the Chinese herbal compund Saikosaponin A was investigated.

Expressions of proto-oncogene c-jun, junB and c-fos were induced by TPA and Saikosaponin A between 30 minutes to 6 hours of treatment. Pre-treatment of 20 microg/ml PD98059, an inhibitor of MEK (the upstream kinase of ERK), prevents the TPA and Saikosaponin A triggered HepG2 growth inhibition by 50% and 30%, respectively. In addition, AP-1 DNA-binding assay, using non-isotopic capillary electrophoresis and laser-induced fluorescence (CE/LIF), demonstrated that the AP-1-related DNA-binding activity was significantly induced by TPA and Saikosaponin A, which can be reduced by PD98059 pre-treatment.

Results suggest that activation of ERK, together with its downstream transcriptional machinery, mediated p15(INK4b) and p16(INK4a) expression that led to HepG2 growth inhibition (Wen-Sheng, 2003).

The effects of Saikosaponin D (SSd) on syndecan-2, matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases-2 (TIMP-2) in livers of rats with hepatocellular carcinoma (HCC) was investigated.

The model group had more malignant nodules than the SSd group. Model-group HCC cells were grade III; SSd-group HCC cells were grades I-II. Controls showed normal hepatic cell phenotypes and no syndecan-2+ staining. Syndecan-2+ staining was greater in the model group (35.2%, P < or = 0.001) than in controls or the SSd group (16.5%, P < or = 0.001). The model group had more intense MMP-2+ staining than controls (0.37 vs 0.27, P< or =0.01) or the SSd group (0.31 vs 0.37, P< or =0.05); and higher MMP-13+ staining (72.55%) than in controls (12.55%, P< or =0.001) and SSd group (20.18%, P< or =0.01).

The model group also had more TIMP-2+ staining (57.2%) than controls (20.9%, P< or =0.001) and SSd group (22.7%, P< or=0.001). Controls and SSd group showed no difference in TIMP-2+ rates.

SSd inhibited HCC development, and downregulated expression of syndecan-2, MMP-2, MMP-13 and TIMP-2 in rat HCC liver tissue (Jia et al., 2012).

T Cell-mediated Autoimmune

Saikosaponin-d (Ssd) is a triterpene saponin derived from the medicinal plant, Bupleurum falcatum L. (Umbelliferae). Previous findings showed that Ssd exhibits a variety of pharmacological and immunomodulatory activities including anti-inflammatory, anti-bacterial, anti-viral and anti-cancer effects.

Results demonstrated that Ssd not only suppressed OKT3/CD28-costimulated human T cell proliferation, it also inhibited PMA, PMA/Ionomycin and Con A-induced mouse T cell activation in vitro. The inhibitory effect of Ssd on PMA-induced T cell activation was associated with down-regulation of NF-kappaB signaling through suppression of IKK and Akt activities. In addition, Ssd suppressed both DNA binding activity and the nuclear translocation of NF-AT and activator protein 1 (AP-1) of the PMA/Ionomycin-stimulated T cells. The cell surface markers, such as IL-2 receptor (CD25), were also down-regulated along with decreased production of pro-inflammatory cytokines of IL-6, TNF-alpha and IFN-gamma.

Results indicate that the NF-kappaB, NF-AT and AP-1 (c-Fos) signaling pathways are involved in the T cell inhibition evoked by Ssd. Ssd could be a potential candidate for further study in treating T cell-mediated autoimmune conditions (Wong, Zhou, Cheung, Li, & Liu, 2009).

Cervical Cancer

Saikosaponin-a and -d, two naturally occurring compounds derived from Bupleurum radix, have been shown to exert anti-cancer activity in several cancer cell lines. However, the effect of a combination of saikosaponins with chemotherapeutic drugs have never been addressed. Investigated as to whether these two saikosaponins have chemo-sensitization effect on cisplatin-induced cancer cell cytotoxicity was carried out.

Two cervical cancer cell lines, HeLa and Siha, an ovarian cancer cell line, SKOV3, and a non-small-cell lung cancer cell line, A549, were treated with saikosaponins or cisplatin individually or in combination. Cell death was quantitatively detected by the release of lactate dehydrogenase (LDH) using a cytotoxicity detection kit. Cellular ROS was analyzed by flow cytometry. Apoptosis was evaluated by AO/EB staining, flow cytometry after Anexin V and PI staining, and Western blot for caspase activation. ROS scavengers and caspase inhibitor were used to determine the roles of ROS and apoptosis in the effects of saikosaponins on cisplatin-induced cell death.

Both saikosaponin-a and -d sensitized cancer cells to cisplatin-induced cell death in a dose-dependent manner, which was accompanied with induction of reactive oxygen species (ROS) accumulation.

Results suggest that saikosaponins sensitize cancer cells to cisplatin through ROS-mediated apoptosis, and the combination of saikosaponins with cisplatin could be an effective therapeutic strategy (Wang et al., 2010).

Colon Cancer

Saikosaponin-a (SSa)-induced apoptosis of HCC cells was associated with proteolytic activation of caspase-9, caspase-3, and PARP cleavages and decreased levels of IAP family members, such as XIAP and c-IAP-2, but not of survivin. SSa treatment also enhanced the activities of caspase-2 and caspase-8, Bid cleavage, and the conformational activation of Bax. Moreover, inhibition of caspase-2 activation by the pharmacological inhibitor z-VDVAD-fmk, or by knockdown of protein levels using a si-RNA, suppressed SSa-induced caspase-8 activation, Bid cleavage, and the conformational activation of Bax. Although caspase-8 is an initiator caspase like caspase-2, the inhibition of caspase-8 activation by knockdown using a si-RNA did not suppress SSa-induced caspase-2 activation.

Results suggest that sequential activation of caspase-2 and caspase-8 is a critical step in SSa-induced apoptosis (Kim & Hong, 2011).

Immune Regulating

Tumor necrosis factor-alpha (TNF- α ) was reported as an anti-cancer therapy due to its cytotoxic effect against an array of tumor cells. However, its undesirable responses of TNF- α on activating NF- κB signaling and pro-metastatic property limit its clinical application in treating cancers. Therefore, sensitizing agents capable of overcoming this undesirable effect must be valuable for facilitating the usage of TNF- α -mediated apoptosis therapy for cancer patients. Previously, saikosaponin-d (Ssd), a triterpene saponin derived from the medicinal plant, Bupleurum falcatum L. (Umbelliferae), exhibited a variety of pharmacological activities such as anti-inflammatory, anti-bacterial, anti-viral and anti-cancer.

Investigation found that Ssd could potentially inhibit activated T lymphocytes via suppression of NF- κ B, NF-AT and AP-1 signaling. Ssd significantly potentiated TNF- α -mediated cell death in HeLa and HepG2 cancer cells via suppression of TNF- α -induced NF- κ B activation and its target genes expression involving cancer cell proliferation, invasion, angiogenesis and survival. Also, Ssd revealed a significant potency in abolishing TNF- α -induced cancer cell invasion and angiogenesis in HUVECs while inducing apoptosis via enhancing the loss of mitochondrial membrane potential in HeLa cells.

Collectively, findings indicate that Ssd has significant potential to be developed as a combined adjuvant remedy with TNF- α for cancer patients (Wong et al., 2013).

Radio-sensitizer

Saikosaponin-d (SSd), a monomer terpenoid purified from the Chinese herbal drug Radix bupleuri, has multiple effects, including anti-cancer properties. Treatment with SSd alone and radiation alone inhibited cell growth and increased apoptosis rate at the concentration used. These effects were enhanced when SSd was combined with radiation. Moreover, SSd potentiated the effects of radiation to induce G0/G1 arrest in SMMC-7721 hepatocellular carcinoma cells, and reduced the G2/M-phase population under hypoxia. SSd potentiates the effects of radiation on SMMC-7721 cells; thus, it is a promising radio-sensitizer. The radio-sensitizing effect of SSd may contribute to its effect on the G0/G1 and G2/M checkpoints of the cell-cycle (Wang et al., 2013).

References

Chen JC, Chang NW, Chung JG, Chen KC. (2003). Saikosaponin-A induces apoptotic mechanism in human breast MDA-MB-231 and MCF-7 cancer cells. The American Journal of Chinese Medicine, 31(3), 363-77.


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


Jia X, Dang S, Cheng Y, et al. (2012). Effects of saikosaponin-d on syndecan-2, matrix metalloproteinases and tissue inhibitor of metalloproteinases-2 in rats with hepatocellular carcinoma. Journal of Traditional Chinese Medicine, 32(3), 415-22.


Kim BM, Hong SH. (2011). Sequential caspase-2 and caspase-8 activation is essential for saikosaponin a-induced apoptosis of human colon carcinoma cell lines. Apoptosis, 16(2), 184-197. doi: 10.1007/s10495-010-0557-x.


Wang BF, Dai ZJ, Wang XJ, et al. (2013). Saikosaponin-d increases the radiosensitivity of smmc-7721 hepatocellular carcinoma cells by adjusting the g0/g1 and g2/m checkpoints of the cell-cycle. BMC Complementary and Alternative Medicine, 13:263. doi:10.1186/1472-6882-13-263


Wang Q, Zheng XL, Yang L, et al. (2010). Reactive oxygen species-mediated apoptosis contributes to chemo-sensitization effect of saikosaponins on cisplatin-induced cytotoxicity in cancer cells. Journal of Experimental & Clinical Cancer Research, 9(29), 159. doi: 10.1186/1756-9966-29-159.


Wen-Sheng, W. (2003). ERK signaling pathway is involved in p15INK4b/p16INK4a expression and HepG2 growth inhibition triggered by TPA and Saikosaponin A. Oncogene, 22(7), 955-963.


Wong VK, Zhang MM, Zhou H, et al. (2013). Saikosaponin-d Enhances the Anti-cancer Potency of TNF- α via Overcoming Its Undesirable Response of Activating NF-Kappa B Signaling in Cancer Cells. Evidence-based Complementary and Alternative Medicine, 2013(2013), 745295. doi: 10.1155/2013/745295.


Wong VK, Zhou H, Cheung SS, Li T, Liu L. (2009). Mechanistic study of saikosaponin-d (Ssd) on suppression of murine T lymphocyte activation. Journal of Cellular Biochemistry, 107(2), 303-15. doi: 10.1002/jcb.22126.

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.

Piperine

Cancer: Breast, prostate

Action: Autophagy inhibitor, anti-proliferative effect

Breast Cancer Stem Cells

Mammosphere formation assays were performed after curcumin, piperine and control treatment in unsorted normal breast epithelial cells and normal stem and early progenitor cells, selected by ALDH positivity. Wnt signaling was examined using a Topflash assay. Both curcumin and piperine inhibited mammosphere formation, serial passaging and percent of ALDH+ cells, by 50% at 5 µM and completely at 10 µM concentration in normal and malignant breast cells. Curcumin and piperine separately, and in combination, inhibit breast stem cell self-renewal but do not cause toxicity to differentiated cells. These compounds could be potential cancer-preventive agents. Mammosphere formation assays may be a quantifiable biomarker to assess cancer-preventive agent efficacy and Wnt signaling assessment a mechanistic biomarker for use in human clinical trials (Kakarala et al., 2010).

HER-2 Overexpressing Breast Cancer

Results showed that piperine strongly inhibited proliferation and induced apoptosis of HER2-overexpressing breast cancer cells through caspase-3 activation and PARP cleavage. Furthermore, piperine inhibited HER2 gene expression at the transcriptional level.   Piperine pre-treatment enhanced sensitization to paclitaxel killing in HER2-overexpressing breast cancer cells. Our findings suggest that piperine may be a potential agent for the prevention and treatment of human breast cancer with HER2 overexpression (Do et al., 2013).

Prostate Cancer

Piperine treatment resulted in a dose-dependent inhibition of the proliferation of prostate cancer DU145, PC-3 and LNCaP cell lines. Cell-cycle arrest at G₀/G₁ was induced and cyclin D1 and cyclin A were down-regulated upon piperine treatment. Notably, the level of p21(Cip1) and p27(Kip1) was increased dose-dependently by piperine treatment in both LNCaP and DU145 but not in PC-3 cells, in line with more robust cell-cycle arrest in the former two cell lines than the latter one. The piperine-induced autophagic flux was further confirmed by assaying LC3-II accumulation and LC3B puncta formation in the presence of chloroquine, a well-known autophagy inhibitor. Taken together, these results indicated that piperine exhibited anti-proliferative effect in human prostate cancer cells by inducing cell-cycle arrest and autophagy (Ouyang et al., 2013).

References

Do MT, Kim HG, Choi JH, et al. (2013). Anti-tumor efficacy of piperine in the treatment of human HER2-overexpressing breast cancer cells. Food Chem, 141(3):2591-9. doi: 10.1016/j.foodchem.2013.04.125.


Kakarala M, Brenner DE, Korkaya H, et al. (2010). Targeting breast stem cells with the cancer-preventive compounds curcumin and piperine. Breast Cancer Res Treat, 122(3): 777–785.


Ouyang DY, Zeng LH, Pan H, et al. (2013). Piperine inhibits the proliferation of human prostate cancer cells via induction of cell-cycle arrest and autophagy. Food Chem Toxicol, 60:424-30. doi: 10.1016/j.fct.2013.08.007.

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.

Hispolon

Cancer: Bladder, breast, liver, gastric

Action: Anti-inflammatory, cytostatic, cytotoxic, pro-oxidative, anti-proliferative

Hispolon is an active phenolic compound of Phellinus igniarius , a mushroom that has recently been shown to have anti-oxidant, anti-inflammatory, and anti-cancer activities.

Liver Cancer

Hispolon inhibited cellular growth of Hep3B cells in a time-dependent and dose-dependent manner, through the induction of cell-cycle arrest at S phase measured using flow cytometric analysis and apoptotic cell death, as demonstrated by DNA laddering. Exposure of Hep3B cells to hispolon resulted in apoptosis as evidenced by caspase activation, PARP cleavage, and DNA fragmentation. Hispolon treatment also activated JNK, p38 MAPK, and ERK expression. Inhibitors of ERK (PB98095), but not those of JNK (SP600125) and p38 MAPK (SB203580), suppressed hispolon-induced S-phase arrest and apoptosis in Hep3B cells.

These findings establish a mechanistic link between the MAPK pathway and hispolon-induced cell-cycle arrest and apoptosis in Hep3B cells (Huang et al., 2011).

Gastric Cancer, Breast Cancer, Bladder Cancer

Hispolon extracted from Phellinus species was found to induce epidermoid and gastric cancer cell apoptosis. Hispolon has also been found to inhibit breast and bladder cancer cell growth, regardless of p53 status. Furthermore, p21(WAF1), a cyclin-dependent kinase inhibitor, was elevated in hispolon-treated cells. MDM2, a negative regulator of p21(WAF1), was ubiquitinated and degraded after hispolon treatment.

Lu et al. (2009) also found that activated ERK1/2 (extracellular signal-regulated kinase1/2) was recruited to MDM2 and involved in mediating MDM2 ubiquitination. The results indicated that cells with higher ERK1/2 activity were more sensitive to hispolon. In addition, hispolon-induced caspase-7 cleavage was inhibited by the ERK1/2 inhibitor, U0126.

In conclusion, hispolon ubiquitinates and down-regulates MDM2 via MDM2-recruited activated ERK1/2. Therefore, hispolon may be a potential anti-tumor agent in breast and bladder cancers.

Gastric Cancer

The efficacy of hispolon in human gastric cancer cells and cell death mechanism was explored. Hispolon induced ROS-mediated apoptosis in gastric cancer cells and was more toxic toward gastric cancer cells than toward normal gastric cells, suggesting greater susceptibility of the malignant cells.

The mechanism of hispolon-induced apoptosis was that hispolon abrogated the glutathione anti-oxidant system and caused massive ROS accumulation in gastric cancer cells. Excessive ROS caused oxidative damage to the mitochondrial membranes and impaired the membrane integrity, leading to cytochrome c release, caspase activation, and apoptosis. Furthermore, hispolon potentiated the cytotoxicity of chemotherapeutic agents used in the clinical management of gastric cancer.

These results suggest that hispolon could be useful for the treatment of gastric cancer either as a single agent or in combination with other anti-cancer agents (Chen et al., 2008).

Anti-proliferative Activity

Hispolon, which lacks one aromatic unit in relation to curcumin, exhibits enhanced anti-inflammatory and anti-proliferative activities. Dehydroxy hispolon was least potent for all three activities. Overall the results indicate that the substitution of a hydroxyl group for a methoxy group at the meta positions of the phenyl rings in curcumin significantly enhanced the anti-inflammatory activity, and the removal of phenyl ring at the 7(th) position of the heptadiene back bone and addition of hydroxyl group significantly increased the anti-proliferative activity of curcumin and hispolon (Ravindran et al., 2010).

References

Chen W, Zhao Z, Li L, et al. (2008). Hispolon induces apoptosis in human gastric cancer cells through a ROS-mediated mitochondrial pathway. Free Radic Biol Med, 45(1):60-72. doi: 10.1016/j.freeradbiomed.2008.03.013.


Huang GJ, Deng JS, Huang SS, Hu ML. (2011). Hispolon induces apoptosis and cell-cycle arrest of human hepatocellular carcinoma Hep3B cells by modulating ERK phosphorylation. J Agric Food Chem, 59(13):7104-13. doi: 10.1021/jf201289e.


Lu TL, Huang GJ, Lu TJ, et al. (2009). Hispolon from Phellinus linteus has anti-proliferative effects via MDM2-recruited ERK1/2 activity in breast and bladder cancer cells. Food Chem Toxicol, 47(8):2013-21. doi: 10.1016/j.fct.2009.05.023.


Ravindran J, Subbaraju GV, Ramani MV, et al. (2010). Bisdemethylcurcumin and structurally related hispolon analogues of curcumin exhibit enhanced prooxidant, anti-proliferative and anti-inflammatory activities in vitro. Biochem Pharmacol, 79(11):1658-66. doi: 10.1016/j.bcp.2010.01.033.

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.

Eugenol

Cancer:
Melanoma, osteosarcoma, leukemia, gastric, colon, liver, oral., lung

Action: Radio-protective

Eugenol is a natural compound available in honey and various plants extracts; in particular, cloves (Syzygium aromaticum (L.) Merrill & Perry).

Melanoma, Skin Tumors, Osteosarcoma, Leukemia, Gastric Cancer

Eugenol (4-allyl-2-methoxyphenol), a phenolic phytochemicals, is the active component of Syzigium aromaticum (cloves). Aromatic plants like nutmeg, basil, cinnamon and bay leaves also contain eugenol. Eugenol has a wide range of applications like perfumeries, flavorings, essential oils and in medicine as a local antiseptic and anesthetic. Increasing volumes of literature show eugenol possesses anti-oxidant, anti-mutagenic, anti-genotoxic, anti-inflammatory and anti-cancer properties.

The molecular mechanism of eugenol-induced apoptosis in melanoma, skin tumors, osteosarcoma, leukemia, gastric and mast cells has been well documented and highlights the anti-proliferative activity and molecular mechanism of eugenol-induced apoptosis against the cancer cells and animal model (Jaganathan et al., 2012).

Colon Cancer

Since most of the drugs used in cancer are apoptosis-inducers, the apoptotic effect and anti-cancer mechanism of eugenol were investigated against colon cancer cells. MTT assay signified the anti-proliferative nature of eugenol against the tested colon cancer cells. PI staining indicated increasing accumulation of cells at sub-G1-phase. Eugenol treatment resulted in reduction of intracellular non-protein thiols and increase in the earlier lipid layer break. Further events like dissipation of MMP and generation of ROS (reactive oxygen species) were accompanied in the eugenol-induced apoptosis. Augmented ROS generation resulted in the DNA fragmentation of treated cells as shown by DNA fragmentation and TUNEL assay. Further activation of PARP (polyadenosine diphosphate-ribose polymerase), p53 and caspase-3 were observed in Western blot analyzes.

These results demonstrate the molecular mechanism of eugenol-induced apoptosis in human colon cancer cells. This research will further enhance eugenol as a potential chemo-preventive agent against colon cancer (Jaganathan et al., 2011).

Radio-protective, Skin Cancer, Liver Cancer, Oral Cancer, Lung Cancer

Ocimum sanctum L. or Ocimum tenuiflorum L , commonly known as Holy Basil in English or Tulsi in the various Indian languages, is an important medicinal plant in the various traditional and folk systems of medicine in Southeast Asia, and another plant from which eugenol is extracted. Scientific studies have shown it to possess anti-inflammatory, analgesic, anti-pyretic, anti-diabetic, hepato-protective, hypolipidemic, anti-stress, and immunomodulatory activities. Preclinical studies have also shown that Ocimum and some of its phytochemicals including eugenol prevented chemical-induced skin, liver, oral., and lung cancers and to mediate these effects by increasing the anti-oxidant activity, altering the gene expressions, inducing apoptosis, and inhibiting angiogenesis and metastasis.

The aqueous extract of Ocimum and its flavanoids, orintin and vicenin, are shown to protect mice against γ-radiation-induced sickness and mortality and to selectively protect the normal tissues against the tumoricidal effects of radiation. This action is related to the important phytochemicals it contains like eugenol, which are also shown to prevent radiation-induced DNA damage.

References

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


Jaganathan SK, Mazumdar A, Mondhe D, Mandal M. (2011). Apoptotic effect of eugenol in human colon cancer cell lines. Cell Biol Int, 35(6):607-15. doi: 10.1042/CBI20100118.


Jaganathan SK, Supriyanto E. (2012). Anti-proliferative and Molecular Mechanism of Eugenol-Induced Apoptosis in Cancer Cells. Molecules, 17(6):6290-6304. doi:10.3390/molecules17066290.

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.

Dehydrocostus (See also costunolide)

Cancers: Breast, cervical., lung, prostate, sarcoma

Action: Anti-metastatic, cytostatic, lymphangiogenesis inhibitors

Saussurea lappa has been used in Chinese traditional medicine for the treatment of abdominal pain, tenesmus, nausea, and cancer. Previous studies have shown that S. lappa also induces G2 growth arrest and apoptosis in gastric cancer cells.

Prostate Cancer

The effects of hexane extracts of S. lappa (HESLs) on the migration of DU145 and TRAMP-C2 prostate cancer cells were investigated. DU145 and TRAMP-C2 cells were cultured in the presence of 0-4 µg/mL HESL with or without 10 ng/mL epidermal growth factor (EGF).

The active compound, dehydrocostus lactone (DHCL), in fraction 7, dose-dependently inhibited the basal and EGF-induced migration of prostate cancer cells. HESL and DHCL reduced matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 secretion but increased TIMP-2 levels in both the absence and presence of EGF.

Results demonstrated that the inhibition of MMP-9 secretion, and the stimulation of TIMP-2 secretion, contribute to reduced migration of DU145 cells treated with HESL and DHCL. This indicates that HESL containing its active principle, DHCL, has potential as an anti-metastatic agent in the treatment of prostate cancer (Kim et al., 2012).

Sarcoma

Human soft tissue sarcomas represent a rare group of malignant tumors that frequently exhibit chemotherapeutic resistance and increased metastatic potential following unsuccessful treatment. The effects of the costunolide and dehydrocostus lactone, which have been isolated from Saussurea lappa using activity-guided isolation, were studied on three soft tissue sarcoma cell lines of various origins. The effects on cell proliferation, cell-cycle distribution, apoptosis induction, and ABC transporter expression were analyzed. Both compounds inhibited cell viability dose- and time-dependently.

IC50 values ranged from 6.2 µg/mL to 9.8 µg/mL. Cells treated with costunolide showed no changes in cell-cycle, little in caspase 3/7 activity, and low levels of cleaved caspase-3 after 24 and 48 hours. Dehydrocostus lactone caused a significant reduction of cells in the G1 phase and an increase of cells in the S and G2/M phase.

These data demonstrate for the first time that dehydrocostus lactone affects cell viability, cell-cycle distribution and ABC transporter expression in soft tissue sarcoma cell lines. Furthermore, it led to caspase 3/7 activity as well as caspase-3 and PARP cleavage, which are indicators of apoptosis. Therefore, this compound may be a promising lead candidate for the development of therapeutic agents against drug-resistant tumors (Kretschmer et al., 2012).

The effects of the sesquiterpene lactones, costunolide and dehydrocostus, on the cell-cycle, MMP expression, and invasive potential of three human STS cell lines of various origins. Both compounds reduced cell proliferation in a time- and dose-dependent manner.

Dehydrocostus lactone significantly inhibited cell proliferation, arrested the cells at the G2/M interface and caused a decrease in the expression of the cyclin-dependent kinase CDK2 and the cyclin-dependent kinase inhibitor p27 (Kip1).

In the presence of costunolide, MMP-2 and MMP-9 levels were significantly increased in SW-982 and TE-671 cells. Dehydrocostus lactone treatment significantly reduced MMP-2 and MMP-9 expression in TE-671 cells, but increased MMP-9 level in SW-982 cells. In addition, the invasion potential was significantly reduced after treatment with both sesquiterpene lactones as investigated by the HTS FluoroBlock insert system (Lohberger et al., 2013).

Breast Cancer

Several Chinese herbs, namely, pu gong ying (Taraxacum officinale), gan cao (Glycyrrhizae uralensis), chai hu (Bupleurum chinense), mu xiang (Auklandia lappa), gua lou (Trichosanthes kirilowii) and huang yao zi (Dioscoreae bulbiferae), are frequently used in complex traditional Chinese medicine formulas, for breast hyperplasia and breast tumor therapy. The effects of these Chinese herbs are all described as 'clearing heat-toxin and resolving masses' in traditional use. However, the chemical profiles of anti-breast cancer constituents in these herbs have not been investigated thus far.

Two potential anti-breast cancer compounds, costunolide (Cos) and dehydrocostus lactone (Dehy), were identified in mu xiang. The combination of the two compounds showed a synergistic effect on inhibiting the proliferation of MCF-7 cells in vitro, exhibiting potential application in the treatment of breast cancer (Peng, Wang, Gu, Wen & Yan, 2013).

Lymphangiogenesis Inhibitors

In this study, we investigated lymphangiogenesis inhibitors from crude drugs used in Japan and Korea. The three crude drugs Saussureae Radix, Psoraleae Semen and Aurantti Fructus Immaturus significantly inhibited the proliferation of temperature-sensitive rat lymphatic endothelial (TR-LE) cells in vitro. These compounds might offer clinical benefits as lymphangiogenesis inhibitors and may be good candidates for novel anti-cancer and anti-metastatic agents (Jeong, 2013).

References

Jeong D, Watari K, Shirouzu T, et al. (2013). Studies on lymphangiogenesis inhibitors from Korean and Japanese crude drugs. Biological & Pharmaceutical Bulletin, 36(1), 152-7.


Kim EJ, Hong JE, Lim SS, et al. (2012). The hexane extract of Saussurea lappa and its active principle, dehydrocostus lactone, inhibit prostate cancer cell migration. Journal of Medicinal Food, 15(1), 24-32. doi: 10.1089/jmf.2011.1735.


Kretschmer N, Rinner B, Stuendl N, et al. (2012). Effect of costunolide and dehydrocostus lactone on cell-cycle, apoptosis, and ABC transporter expression in human soft tissue sarcoma cells. Planta Medica, 78(16), 1749-1756. doi: 10.1055/s-0032-1315385.


Lohberger B, Rinner B, Stuendl N, et al. (2013). Sesquiterpene lactones downregulate g2/m cell-cycle regulator proteins and affect the invasive potential of human soft tissue sarcoma cells. PLoS One, 8(6), e66300. doi: 10.1371/journal.pone.0066300.


Peng ZX, Wang Y, Gu X, Wen YY, Yan C. (2013). A platform for fast screening potential anti-breast cancer compounds in traditional Chinese medicines. Biomedical Chromatography. doi: 10.1002/bmc.2990.

Berberine

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

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

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

Anti-inflammatory

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

Angiogenesis, Chemo-enhancing

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

Cell-cycle Arrest

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

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

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

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

Anti-metastatic

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

Hepatoma, Leukaemia

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

Leukemia

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

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

Prostate Cancer

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

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

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

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

Breast Cancer

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

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

Breast Cancer Metastasis

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

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

Melanoma

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

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

Cell-cycle Arrest, Squamous-cell Carcinoma

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

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

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

Cervical Cancer, Radio-sensitizer

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

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

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

Anti-oxidative; Breast, Liver and Colon Cancer

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

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

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

Source:

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

References

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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


Tan W, Lu J, Huang M, et al. (2011). Anti-cancer natural products isolated from chinese medicinal herbs. Chinese Medicine, 6(1):27.


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


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


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


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


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

Antrodia camphorata

 

Cancer: Leukemia, colorectal., ER+ ovarian cancer

Action: Anti-cancer

Antrodia Camphorata [(M. Zang & C.H. Su) Sheng H. Wu, Ryvarden & T.T.] is a native Taiwanese mushroom which is used in Asian folk medicine. It is also known as Ganoderma camphoratum (M. Zang & C.H. Su) and Taiwanofungus camphoratus [(M. Zang & C.H. Su) Sheng H. Wu, Z.H. Yu, Y.C. Dai & C.H. Su].

Anti-tumor

Mycotherapy is defined as the study of the use of extracts and compounds obtained from mushrooms as medicines or health-promoting agents. An increasing number of studies in the past few years have revealed mushroom extracts as potent anti-tumor agents. Also, numerous studies have been conducted on bioactive compounds isolated from mushrooms reporting the heteropolysaccharides, β-glucans, α-glucans, proteins, complexes of polysaccharides with proteins, fatty acids, nucleoside antagonists, terpenoids, sesquiterpenes, lanostanoids, sterols and phenolic acids, as promising anti-tumor agents (Popović et al., 2013).

Leukemia

Antrodia camphorata (AC) is a native Taiwanese mushroom, which is used in Asian folk medicine as a chemo-preventive agent. The triterpenoid-rich fraction (FEA) was obtained from the ethanolic extract of AC and characterized by high performance liquid chromatography (HPLC). FEA caused DNA damage in leukemia HL60 cells which was characterized by phosphorylation of H2A.X and Chk2. It also exhibited apoptotic effect which was correlated to the enhancement of PARP cleavage and to the activation of caspase 3.

Taken together, these results provide the first evidence that pure AC component inhibits tumor growth in an in vivo model, thereby backing the traditional anti-cancer use of AC in Asian countries (Du et al., 2012).

Colon Cancer

Antrodia camphorata (AC) grown on germinated brown rice (CBR) was studied in HT-29 human colon cancer cells. CBR 80% ethanol EtOAc fraction showed the strongest inhibitory activity against HT-29 cell proliferation. Induction of G0/G1 cell-cycle arrest on human colon carcinoma cell was observed in CBR EtOAc fraction-treated cells. We found that CBR decreased the level of proteins involved in G0/G1 cell-cycle arrest and apoptosis. CBR EtOAc fraction inhibited the β-catenin signaling pathway, supporting its suppressive activity on the level of cyclin D1 (Park, Lim, & Park, 2013).

A new enynyl-benzenoid, antrocamphin O (1,4,7-dimethoxy-5-methyl-6-(3'-methylbut-3-en-1-ynyl)benzo[d][1,3]dioxide), and the known benzenoids antrocamphin A and 7-dimethoxy-5-methyl-1,3-benzodioxole, were isolated from the fruiting bodies of Antrodia camphorata (Taiwanofungus camphoratus). The benzenoids were tested successfully for cytotoxicity against the HT29, HTC15, DLD-1, and COLO 205 colon cancer cell lines (Chen et al., 2013).

ER+ Ovarian Cancer

MTT and colony formation assays showed that Antrodia camphorata (AC) induced a dose-dependent reduction in SKOV-3 cell growth. Immunoblot analysis demonstrated that HER-2/neu activity and tyrosine phosphorylation were significantly inhibited by AC. Furthermore, AC treatment significantly inhibited the activation of PI3K/Akt and their downstream effector β-catenin (Yang et al., 2013).

References

Chen PY, Wu JD, Tang KY, et al. (2013). Isolation and synthesis of a bioactive benzenoid derivative from the fruiting bodies of Antrodia camphorata. Molecules, 18(7):7600-8. doi: 10.3390/molecules18077600.


Du YC, Chang FR, Wu TY, et al. (2012). Anti-leukemia component, dehydroeburicoic acid from Antrodia camphorata induces DNA damage and apoptosis in vitro and in vivo models. Phytomedicine. doi:10.1016/j.phymed.2012.03.014


Park DK, Lim YH, Park HJ. (2013). Antrodia camphorata Grown on Germinated Brown Rice Inhibits HT-29 Human Colon Carcinoma Proliferation Through Inducing G0/G1 Phase Arrest and Apoptosis by Targeting the β -Catenin Signaling. J Med Food, 16(8):681-91. doi: 10.1089/jmf.2012.2605.


Popovi ć V, Zivkovi ć J, Davidovi ć S, et al. (2013). Mycotherapy Of Cancer: An Update On Cytotoxic And Anti-tumor Activities Of Mushrooms, Bioactive Principles And Molecular Mechanisms Of Their Action. Curr Top Med Chem.


Yang HL, Lin KY, Juan YC, et al. (2013). The anti-cancer activity of Antrodia camphorata against human ovarian carcinoma (SKOV-3) cells via modulation of HER-2/neu signaling pathway. J Ethnopharmacol, 148(1):254-65. doi: 10.1016/j.jep.2013.04.023.

Aloe-emodin (See also Emodin)

Cancer:
Nasopharyngeal., ER α degradation, Lung, breast, oral., glioblastoma, liver cancer prevention

Action: Cytostatic, radio-sensitizing, chemo-sensitizing

Nasopharyngeal Carcinoma

Aloe-emodin (AE), a natural., biologically active compound from Aloe vera leaves has been shown to induce apoptosis in several cancer cell lines in vitro. Investigation showed that AE induced G2/M phase arrest by increasing levels of cyclin B1 bound to Cdc2, and also caused an increase in apoptosis of nasopharyngeal carcinoma (NPC) cells, which was characterized by morphological changes, nuclear condensation, DNA fragmentation, caspase-3 activation, cleavage of poly (ADP-ribose) polymerase (PARP) and increased sub-G(1) population. Treatment of NPC cells with AE also resulted in a decrease in Bcl-X(L) and an increase in Bax expression.

Collectively, results indicate that the caspase-8-mediated activation of the mitochondrial death pathway plays a critical role in AE-induced apoptosis of NPC cells (Lin et al., 2010).

Glioblastoma

Aloe emodin arrested the cell-cycle in the S phase and promoted the loss of mitochondrial membrane potential in glioblastoma U87 cells that indicated the early event of the mitochondria-induced apoptotic pathway. It plays an important role in the regulation of cell growth and death (Ismail et al., 2013).

Breast Cancer

The anthraquinones emodin and aloe-emodin are also abundant in the rhizome Rheum palmatum and can induce cytosolic estrogen receptor α (ER α) degradation; it primarily affected nuclear ER α distribution similar to the action of estrogen when protein degradation was blocked. In conclusion, our data demonstrate that emodin and aloe-emodin specifically suppress breast cancer cell proliferation by targeting ER α protein stability through distinct mechanisms (Huang et al., 2013).

Lung Cancer

Photoactivated aloe-emodin induced anoikis and changes in cell morphology, which were in part mediated through its effect on cytoskeleton in lung carcinoma H460 cells. The expression of protein kinase Cδ (PKCδ) was triggered by aloe-emodin and irradiation in H460 cells. Furthermore, the photoactivated aloe-emodin-induced cell death and translocation of PKCδ from the cytosol to the nucleus was found to be significantly inhibited by rottlerin, a PKCδ-selective inhibitor (Chang et al., 2012).

Oral Cancer; Radio-sensitizing, Chemo-sensitizing

The treatment of cancer with chemotherapeutic agents and radiation has two major problems: time-dependent development of tumor resistance to therapy (chemoresistance and radioresistance) and nonspecific toxicity toward normal cells. Many plant-derived polyphenols have been studied intensively for their potential chemo-preventive properties and are pharmacologically safe.

These compounds include genistein, curcumin, resveratrol, silymarin, caffeic acid phenethyl ester, flavopiridol, emodin, green tea polyphenols, piperine, oleandrin, ursolic acid, and betulinic acid. Recent research has suggested that these plant polyphenols might be used to sensitize tumor cells to chemotherapeutic agents and radiation therapy by inhibiting pathways that lead to treatment resistance. These agents have also been found to be protective from therapy-associated toxicities.

Treatment with aloe-emodin at 10 to 40 microM resulted in cell-cycle arrest at G2/M phase. The alkaline phosphatase (ALP) activity in KB cells increased upon treatment with aloe-emodin when compared to controls. This is one of the first studies to focus on the expression of ALP in human oral carcinomas cells treated with aloe-emodin. These results indicate that aloe-emodin has anti-cancer effect on oral cancer, which may lead to its use in chemotherapy and chemo-prevention of oral cancer (Xiao et al., 2007).

Liver Cancer Prevention

In Hep G2 cells, aloe-emodin-induced p53 expression and was accompanied by induction of p21 expression that was associated with a cell-cycle arrest in G1 phase. In addition, aloe-emodin had a marked increase in Fas/APO1 receptor and Bax expression. In contrast, with p53-deficient Hep 3B cells, the inhibition of cell proliferation of aloe-emodin was mediated through a p21-dependent manner that did not cause cell-cycle arrest or increase the level of Fas/APO1 receptor, but rather promoted aloe-emodin-induced apoptosis by enhancing expression of Bax.

These findings suggest that aloe-emodin may be useful in liver cancer prevention (Lian et al., 2005).

References

Chang WT, You BJ, Yang WH, et al. (2012). Protein kinase C delta-mediated cytoskeleton remodeling is involved in aloe-emodin-induced photokilling of human lung cancer cells. Anti-cancer Res, 32(9):3707-13.

Huang PH, Huang CY, Chen MC, et al. (2013). Emodin and Aloe-Emodin Suppress Breast Cancer Cell Proliferation through ER α Inhibition. Evid Based Complement Alternat Med, 2013:376123. doi: 10.1155/2013/376123.

Ismail S, Haris K, Abdul Ghani AR, et al. (2013). Enhanced induction of cell-cycle arrest and apoptosis via the mitochondrial membrane potential disruption in human U87 malignant glioma cells by aloe emodin. J Asian Nat Prod Res.

Lian LH, Park EJ, Piao HS, Zhao YZ, Sohn DH. (2005). Aloe Emodin‐Induced Apoptosis in Cells Involves a Mitochondria‐Mediated Pathway. Basic & Clinical Pharmacology & Toxicology, 96(6):495–502.

Lin, ML, Lu, YC, Chung, JG, et al. (2010). Aloe-emodin induces apoptosis of human nasopharyngeal carcinoma cells via caspase-8-mediated activation of the mitochondrial death pathway. Cancer Letters, 291(1), 46-58. doi: 10.1016/j.canlet.2009.09.016.

Xiao B, Guo J, Liu D, Zhang S. (2007). Aloe-emodin induces in vitro G2/M arrest and alkaline phosphatase activation in human oral cancer KB cells. Oral Oncol, 43(9):905-10.

Acetyl-keto-beta-boswellic acid (AKBA)

Cancer: Colorectal, prostate, gastric

Action: Anti-cancer

Apoptotic

Acetyl-keto-beta-boswellic acid (AKBA), a triterpenoid isolated from Boswellia carterri Birdw and Boswellia serrata, has been found to inhibit tumor cell growth and to induce apoptosis. Boswellic acids trigger apoptosis via a pathway dependent on caspase-8 activation, and independent of Fas/Fas ligand interaction in colon cancer HT-29 cells (Liu et al., 2002).

Colon Cancer

Although there is increasing evidence showing that boswellic acid might be a potential anti-cancer agent, the mechanisms involved in its action are unclear. It has been shown that acetyl-keto-beta-boswellic acid (AKBA) inhibits cellular growth in several colon cancer cell lines. Cell cycle analysis by flow cytometry showed that cells were arrested at the G1 phase after AKBA treatment.

These results demonstrate that AKBA inhibits cellular growth in colon cancer cells. These findings may have implications for the use of boswellic acids as potential anti-cancer agents in colon cancer (Liu et al., 2006).

AKBA significantly inhibited human colon adenocarcinoma growth, showing arrest of the cell-cycle in G1-phase and induction of apoptosis. AKBA administration in mice effectively delayed the growth of HT-29 xenografts without signs of toxicity (Yuan et al., 2013).

Gastric Cancer

AKBA exhibited anti-cancer activity in vitro and in vivo. With oral application in mice, AKBA significantly inhibited gastric cancer cells line SGC-7901 and MKN-45 xenografts without toxicity.

This effect might be associated with its roles in cell-cycle arrest and apoptosis induction. The results also showed activation of p21(Waf1/Cip1) and p53 in mitochondria and increased cleaved caspase-9, caspase-3, and PARP and Bax/Bcl-2 ratio after AKBA treatment. Upon AKBA treatment, β-catenin expression in nuclei was inhibited, and membrane β-catenin was activated (Zhang et al., 2013).

Prostate

The apoptotic effects and the mechanisms of action of AKBA were studied in LNCaP and PC-3 human prostate cancer cells. AKBA induced apoptosis in both cell lines at concentrations above 10 microg/mL. AKBA-induced apoptosis was correlated with the activation of caspase-3 and caspase-8 as well as with poly(ADP)ribose polymerase (PARP) cleavage.

AKBA treatment increased the levels of CAAT/enhancer binding protein homologous protein (CHOP) and activated a DR5 promoter reporter but did not activate a DR5 promoter reporter with the mutant CHOP binding site. These results suggest that AKBA induces apoptosis in prostate cancer cells through a DR5-mediated pathway, which probably involves the induced expression of CHOP (Lu et al., 2008).

References

Liu J-J, Nilsson A, Oredsson S, et al. (2002). Boswellic acids trigger apoptosis via a pathway dependent on caspase-8 activation but independent on Fas/Fas ligand interaction in colon cancer HT-29 cells. Carcinogenesis. 23(12): 2087–2093. doi:10.1093/carcin/23.12.2087.

 

 

Liu JJ, Huang B, Hooi SC. (2006). Acetyl-keto-beta-boswellic acid inhibits cellular proliferation through a p21-dependent pathway in colon cancer cells. Br J Pharmacol, 148(8):1099-107.

 

Lu M, Xia L, Hua H, Jing Y. (2008). Acetyl-keto-beta-boswellic acid induces apoptosis through a death receptor 5-mediated pathway in prostate cancer cells. Cancer Res, 68(4):1180-6. doi: 10.1158/0008-5472.CAN-07-2978.

 

Yuan Y, Cui SX, Wang Y, et al. (2013). Acetyl-11-keto-beta-boswellic acid (AKBA) prevents human colonic adenocarcinoma growth through modulation of multiple signaling pathways. Biochim Biophys Acta, 1830(10):4907-16. doi: 10.1016/j.bbagen.2013.06.039.

 

Zhang YS, Xie JZ, Zhong JL, et al. (2013) Acetyl-11-keto-β-boswellic acid (AKBA) inhibits human gastric carcinoma growth through modulation of the Wnt/β -catenin signaling pathway. Biochim Biophys Acta, 1830(6):3604-15. doi: 10.1016/j.bbagen.2013.03.003.

Decursin

Cancer: Prostate, breast, fibrosarcoma, sarcoma

Action: MDR, inflammation, anti-cancer, angiogenesis

Decursin is isolated from Angelica gigas (Nakai).

Angelica gigas NAKAI is used to treat dysmenorrhea, amenorrhea, menopause, abdominal pain, injuries, migraine, and arthritis. The physicochemical and toxicological characterization of compounds in A. gigas NAKAI, decursin, decursinol angelate, diketone decursin, ether decursin, epoxide decursin and oxim decursin, have been extensively studied (Mahat et al., 2012).

Sarcoma; Anti-cancer

The in vivo anti-tumor activities of decursinol angelate (1) and decursin (2) isolated from the roots of Angelica gigas were investigated. These two compounds, when administered consecutively for 9 days at 50 and 100 mg/kg i.p. in mice, caused a significant increase in the life span and a significant decrease in the tumor weight and volume of mice inoculated with Sarcoma-180 tumor cells. These results suggest that decursinol angelate (1) and decursin (2) from A. gigas have anti-tumor activities (Lee et al., 2003).

Fibrosarcoma

Decursin and related coumarin compounds in herbal extracts have a number of biological activities against inflammation, angiogenesis and cancer. The human fibrosarcoma cell line, HT1080, was treated with TNFα (tumor necrosis factor α) in the presence or absence of CSL-32. Treatment of HT1080 cells with a derivative of decursin (CSL-32) inhibited their proliferation, without affecting cell viability, and TNF α-induced expression of pro-inflammatory mediators, such as MMP-9 (matrix metalloproteinase-9) and IL-8 (interleukin-8) (Lee et al., 2012).

Prostate Cancer

Androgen and androgen receptor (AR) signaling are crucial for the genesis of prostate cancer (PCa), which can often develop into androgen-ligand-independent diseases that are lethal to patients. As current chemotherapy is largely ineffective for PCa and has serious toxic side-effects, a collaborative effort has been initiated to identify and develop novel, safe and naturally occurring agents that target AR signaling from Oriental medicinal herbs for the chemoprevention and treatment of PCa. The discovery of decursin from an Oriental formula containing Korean Angelica gigas Nakai (Dang Gui) root as a novel anti-androgen/AR agent has been highlighted and the mechanisms to account for the specific anti-AR actions have been identified: rapid block of AR nuclear translocation, inhibition of binding of 5-dihydrotestesterone to AR, and increased proteasomal degradation of AR protein. Structure-activity analyzes reveal a critical requirement of the side-chain on decursin or its structural isomer decursinol angelate for anti-AR, cell-cycle arrest and pro-apoptotic activities.

This work demonstrates the feasibility of using activity-guided fractionation in cell culture assays combined with mechanistic studies to identify novel anti-androgen/AR agents from complex herbal mixtures (Lu et al., 2007).

MDR

Combination cancer therapy is one of the attractive approaches to overcome drug resistance of cancer cells. In the present study, Jang et al (2013) investigated the synergistic effect of decursin from Angelica gigas and doxorubicin on the induction of apoptosis in three human multiple myeloma cells. The combined treatment reduced mitochondrial membrane potential., suppressed the phosphorylation of JAK2, STAT3, and Src, activated SHP-2, and attenuated the expression of cyclind-D1 and survivin in U266 cells.

Overall, the combination treatment of decursin and doxorubicin can enhance apoptotic activity via mTOR and/or STAT3 signaling pathway in multiple myeloma cells.

Breast Cancer

Decursin significantly reduced protein expression and enzymatic activity of Pin1 in MDA-MB-231 cells. Kim et al (2013) found that decursin treatment enhanced the p53 expression level and failed to down-regulate Pin1 in the cells transfected with p53 siRNA, indicating the importance of p53 in the decursin-mediated Pin1 inhibition in MDA-MB-231 cells. Decursin stimulated association between peptidyl-prolyl cis/trans isomerase Pin1 to p53. Moreover, decursin facilitated p53 transcription in MDA-MB-231 cells. Overall, the study suggests the potential of decursin as an attractive cancer therapeutic agent for breast cancer by targeting Pin1.

References

Jang J, Jeong SJ, Kwon HY, Jung JH, et al. (2013). Decursin and Doxorubicin Are in Synergy for the Induction of Apoptosis via STAT3 and/or mTOR Pathways in Human Multiple Myeloma Cells. Evid Based Complement Alternat Med. 2013:506324. doi: 10.1155/2013/506324.

Kim JH, Jung JH, Kim SH, Jeong SJ. (2013). Decursin Exerts Anti-cancer Activity in MDA-MB-231 Breast Cancer Cells Via Inhibition of the Pin1 Activity and Enhancement of the Pin1/p53 Association.Phytother Res. doi: 10.1002/ptr.4986.

Lee S, Lee YS, Jung SH, et al. (2003). Anti-tumor activities of decursinol angelate and decursin from Angelica gigas. Arch Pharm Res, 26(9):727-30.

Lee SH, Lee JH, Kim EJ, et al. (2012). A novel derivative of decursin, CSL-32, blocks migration and production of inflammatory mediators and modulates PI3K and NF- κB activities in HT1080 cells. Cell Biol Int, 36(7):683-8. doi: 10.1042/CBI20110257.

Lu JX, Kim SH, Jiang C, Lee JJ, Guo JM. (2007). Oriental herbs as a source of novel anti-androgen and prostate cancer chemo-preventive agents. Acta Pharmacologica Sinica, 28, 1365–1372. doi:10.1111/j.1745-7254.2007.00683.x

Mahat B, Chae JW, Baek IH, et al. (2012). Physicochemical characterization and toxicity of decursin and their derivatives from Angelica gigas. Biol Pharm Bull, 35(7):1084-90.

Costunolide and Dehydrocostus Lactone

Cancers:
Breast, cervical., lung, ovarian, bladder, leukemia, prostate, gastric

Action: Anti-inflammatory, pro-oxidative, MDR, lymphangiogenesis inhibitor, anti-metastasis, mediates apoptosis, anti-metastatic

Components of Saussurea lappa Clarke, Vladimiria souliei (Franchet) Lingelsheim (Compositae)

Breast cancer; Anti-metastatic

It was found that costunolide inhibited the growth and telomerase activity of MCF-7 and MDA-MB-231 cells in a concentration- and time-dependent manner. The expression of hTERT mRNA was also inhibited but hTR mRNA was not. In addition, the bindings of transcription factors in hTERT promoters were significantly decreased in both cells by the treatment of costunolide. These results suggest that costunolide inhibited the growth of both MCF-7 and MDA-MB-231 cells and this effect was mediated at least in part by a significant reduction in telomerase activity (Choi et al., 2005).

Breast Cancer

Costunolide has been demonstrated to suppress tumor growth and metastases of MDA-MB-231 highly metastatic human breast cancer cells via inhibiting TNF-α induced NF-kB activation. Costunolide also inhibited MDA-MB-231 tumor growth and metastases without affecting body weights in the in vivo mouse orthotopic tumor growth assays.

In addition, costunolide inhibited in vitro TNF-α induced invasion and migration of MDA-MB-231 cells. Costunolide further suppressed TNF-α induced NF-kB signaling activation, resulting in a reduced expression of MMP-9, a well-known NF-kB-dependent gene to mediate breast cancer cell growth and metastases. Taken together, these results suggest that SLC and its derivative costunolide suppress breast cancer growth and metastases by inhibiting TNF-α induced NF-k B activation, suggesting that costunolide as well as SLC may be promising anti-cancer drugs, especially for metastatic breast cancer (Choi et al., 2013).

Several Chinese herbs, namely, Herba Taraxaci Mongolici (Pu Gong Ying), Radix Glycyrrhizae Uralensis (Gan Cao), Radix Bupleuri (Chai Hu), Radix Aucklandiae Lappae/ Radix Aucklandiae Lappae (Mu Xiang), Fructus Trichosanthis (Gua Lou) and Rhizoma Dioscoreae Bulbiferae (Huang Yao Zi) are frequently used in complex traditional Chinese medicine formulas for breast hyperplasia and breast tumor therapy.

The pharmacological effects of these Chinese herbs are all described as 'clearing heat-toxin and resolving masses' in traditional use. A bioactivity-oriented screening platform, which was based on a human breast cancer MCF-7 cellular model was developed to rapidly screen the 6 Chinese herbs. Two potential anti-breast cancer compounds, which were costunolide (Cos) and dehydrocostus lactone (Dehy), were identified in Radix Aucklandiae Lappae.

Combination of the two compounds showed a synergism on inhibiting the proliferation of MCF-7 cells in vitro, which exhibits a potential application prospect for breast cancer therapy. This bioactivity-oriented screening strategy is rapid, economical., reliable and specific for screening potential anti-breast cancer compounds in traditional Chinese medicines (Peng et al., 2013).

Dehydrocostuslactone (DHE) suppresses the expression of cyclin D, cyclin A, cyclin-dependent kinase 2, and cdc25A and increases the amount of p53 and p21, resulting in G(0)/G(1)-S phase arrest in MCF-7 cells. In contrast, DHE caused S-G(2)/M arrest by increasing p21 expression and chk1 activation and inhibiting cyclin A, cyclin B, cdc25A, and cdc25C expression in MDA-MB-231 cells. Reduction of SOCS-1 and SOCS-3 expression by small interfering RNA inhibits DHE-mediated signal transducer and activator of transcription-3 inhibition, p21 up-regulation, and cyclin-dependent kinase 2 blockade, supporting the hypothesis that DHE inhibits cell-cycle progression and cell death through SOCS-1 and SOCS-3.

Significantly, animal studies have revealed a 50% reduction in tumor volume after a 45-day treatment period. Taken together, this study provides new insights into the molecular mechanism of the DHE action that may contribute to the chemoprevention of breast cancer (Kuo et al., 2009).

ER- Breast Cancer

Costunolide induced apoptosis through the extrinsic pathway, including the activation of Fas, caspase-8, caspase-3, and degradation of PARP. However, it did not have the same effect on the intrinsic pathway as revealed by analysis of mitochondrial membrane potential (Δψ m) with JC-1 dye and expression of Bcl2 and Bax proteins level.

Furthermore, costunolide induced cell-cycle arrest in the G2/M phase via decrease in Cdc2, cyclin B1 and increase in p21WAF1 expression, independent of p53 pathway in p53-mutant MDA-MB-231 cells, and increases Cdc2-p21WAF1 binding/

Through this study it was confirmed that costunolide induces G2/M cell-cycle arrest and apoptotic cell death via extrinsic pathway in MDA-MB-231 cells, suggesting that it could be a promising anti-cancer drug especially for ER negative breast cancer (Choi et al., 2012).

Bladder Cancer

Costunolide, a member of sesquiterpene lactone family, possesses potent anti-cancer properties. The effects of costunolide were investigated on the cell viability and apoptosis in human bladder cancer T24 cells. Treatment of T24 cells with costunolide resulted in a dose-dependent inhibition of cell viability and induction of apoptosis, which was associated with the generation of ROS and disruption of mitochondrial membrane potential (Δψm).

These effects were significantly blocked when the cells were pre-treated with N-acetyl- cysteine (NAC), a specific ROS inhibitor. Exposure of T24 cells to costunolide was also associated with increased expression of Bax, down-regulation of Bcl-2, and of   survivin and significant activation of caspase-3, and its downstream target PARP. These findings provide the rationale for further in vivo and clinical investigation of costunolide against human bladder cancer (Rasul et al., 2013).

Sarcomas; MDR

Human soft tissue sarcomas represent a rare group of malignant tumors that frequently exhibit chemotherapeutic resistance and increased metastatic potential following unsuccessful treatment.

The effects on cell proliferation, cell-cycle distribution, apoptosis induction, and ABC transporter expression were analyzed. Cells treated with costunolide showed no changes in cell-cycle, little in caspase 3/7 activity, and low levels of cleaved caspase-3 after 24 and 48 hours. Dehydrocostus lactone caused a significant reduction of cells in the G1 phase and an increase of cells in the S and G2/M phase. Moreover, it led to enhanced caspase 3/7 activity, cleaved caspase-3, and cleaved PARP indicating apoptosis induction.

These data demonstrate that dehydrocostus lactone affects cell viability, cell-cycle distribution and ABC transporter expression in soft tissue sarcoma cell lines. Furthermore, it led to caspase 3/7 activity as well as caspase-3 and PARP cleavage, which are indicators of apoptosis. Therefore, this compound may be a promising lead candidate for the development of therapeutic agents against drug-resistant tumors (Kretschmer et al., 2013).

Leukemia, Lung Cancer

Costunolide, an active compound isolated from the stem bark of Magnolia sieboldii, has been found to induce apoptosis via reactive oxygen species (ROS) and Bcl-2-dependent mitochondrial permeability transition in human leukemia cells. Mitogen-activated protein kinases (MAPKs) were investigated for their involvement in the costunolide-induced apoptosis in human promonocytic leukemia U937 cells.

Treatment with costunolide resulted in the significant activation of c-Jun N-terminal kinase (JNK), but not of extracellular-signal-related kinase (ERK1/2) or p38. In vitro kinase assays showed that JNK activity was low in untreated cells but increased dramatically after 30 minutes of costunolide treatment. U937 cells co-treated with costunolide and sorbitol, a JNK activator, exhibited higher levels of cell death. In addition, inhibition of the JNK pathway using a dominant-negative mutation of c-jun and JNK inhibitor SP600125, significantly prevented costunolide-induced apoptosis.

Furthermore, pre-treatment with the anti-oxidant NAC (N-acetyl-L-cysteine) blocked the costunolide-stimulated activation of JNK while the overexpression of Bcl-2 failed to reverse JNK activation. These results indicate that costunolide-induced JNK activation acts downstream of ROS but upstream of Bcl-2, and suggest that ROS-mediated JNK activation plays a key role in costunolide-induced apoptosis. Moreover, the administration of costunolide (intraperitoneally once a day for 7 days) significantly suppressed tumor growth and increased survival in 3LL Lewis lung carcinoma-bearing model (Choi et al., 2009).

Prostate Cancer

Several pharmacological and biochemical assays were used to characterize the apoptotic-signaling pathways of costunolide in prostate cancer cells. Costunolide showed effective anti-proliferative activity against hormone dependent (LNCaP) and independent (PC-3 and DU-145) prostate cancer cells (ATCC¨) by sulforhodamine B assay, clonogenic test and flow cytometric analysis of carboxyfluorescein succinimidyl ester labeling. In PC-3 cells data showed that costunolide induced a rapid overload of nuclear Ca(2+), DNA damage response and ATR phosphorylation.

This indicated the crucial role of intracellular Ca(2+) mobilization and thiol depletion but not of reactive oxygen species production in apoptotic signaling. Data suggest that costunolide induces the depletion of intracellular thiols and overload of nuclear Ca(2+) that cause DNA damage and p21 up-regulation. The association of p21 with the cyclin dependent kinase 2/cyclin E complex blocks cyclin dependent kinase 2 activity and inhibits Rb phosphorylation, leading to G1 arrest of the cell-cycle and subsequent apoptotic cell death in human prostate cancer cells (Hsu et al., 2011).

Gastric Cancer, Prostate Cancer

Radix Aucklandiae Lappae/Saussurea lappa has been used in Chinese traditional medicine for the treatment of abdominal pain, tenesmus, nausea, and cancer; previous studies have shown that S. lappa also induces G(2) growth arrest and apoptosis in gastric cancer cells. The effects of hexane extracts of S. lappa (HESLs) on the migration of DU145 and TRAMP-C2 prostate cancer cells were investigated.

The active compound, dehydrocostus lactone (DHCL), in fraction 7 dose-dependently inhibited the basal and EGF-induced migration of prostate cancer cells. HESL and DHCL reduced matrix metalloproteinase (MMP)-9 and tissue inhibitor of metalloproteinase (TIMP)-1 secretion but increased TIMP-2 levels in both the absence and presence of EGF. These results demonstrate that the inhibition of MMP-9 secretion and the stimulation of TIMP-2 secretion contribute to reduced migration of DU145 cells treated with HESL and DHCL.

This indicates that HESL containing its active principle, DHCL, has potential as an anti-metastatic agent for the treatment of prostate cancer (Kim et al., 2012).

Anti-metastatic

Lymphangiogenesis inhibitors from crude drugs used in Japan and Korea were investigated for their impact on metastasis. The three crude drugs Saussureae Radix, Psoraleae Semen and Aurantti Fructus Immaturus significantly inhibited the proliferation of temperature-sensitive rat lymphatic endothelial (TR-LE) cells in vitro.

Among isolated compounds, several compounds; costunolide, dehydrocostus lactone, psoracorylifol D, bavachinin, bakuchiol, showed an inhibitory effect on the proliferation and the capillary-like tube formation of TR-LE cells. In addition, all compounds showed selective inhibition of the proliferation of TR-LE cells compared to Hela and Lewis lung carcinoma (LLC) cells.

These compounds might offer clinical benefits as lymphangiogenesis inhibitors and may be good candidates for novel anti-cancer and anti-metastatic agents (Jeong et al., 2013).

Ovarian Cancer, MDR

The apoptosis-inducing effect of costunolide, a natural sesquiterpene lactone, was studied in platinum-resistant human ovarian cancer cells relative to cisplatin.

The MTT assay for cell viability, PI staining for cell-cycle profiling, and annexin V assay for apoptosis analysis were performed. Costunolide induced apoptosis of platinum-resistant cells in a time and dose-dependent manner and suppressed tumor growth in the SKOV3 (PT)-bearing mouse model. In addition, costunolide triggered the activation of caspase-3, caspase-8, and caspase-9. Pre-treatment with caspase inhibitors neutralized the pro-apoptotic activity of costunolide. We further demonstrated that costunolide induced a significant increase in intracellular reactive oxygen species (ROS). Moreover, costunolide synergized with cisplatin to induce cell death in platinum-resistant ovarian cancer cells.

Data suggests that costunolide, alone or in combination with cisplatin, may be of therapeutic potential in platinum-resistant ovarian cancers (Yang, Kim, Lee, & Choi, 2011).

Anti-inflammatory, Anti-oxidant, Mediates Apoptosis

Cheon et al. (2013) found that costunolide significantly inhibited RANKL-induced BMM differentiation into osteoclasts in a dose-dependent manner without causing cytotoxicity. Costunolide did not regulate the early signaling pathways of RANKL, including the mitogen-activated protein kinase and NF-κB pathways.

However, costunolide suppressed nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1) expression via inhibition of c-Fos transcriptional activity without affecting RANKL-induced c-Fos expression. The inhibitory effects of costunolide were rescued by overexpression of constitutively active (CA)-NFATc1. Taken together, these results suggest that costunolide inhibited RANKL-induced osteoclast differentiation by suppressing RANKL-mediated c-Fos transcriptional activity.

References

Cheon YH, Song MJ, Kim JY, Kwak SC, Park JH, Lee CH, Kim JJ, Kim JY, Choi MK, Oh J, Kim YC, Yoon KH., Kwak HB, Lee MS. (2013). Costunolide inhibits osteoclast differentiation by suppressing c-Fos transcriptional activity. Phytotherapy, July, (6). doi: 10.1002/ptr.5034.

Choi SH, Im E, Kang HK, et al. (2005). Inhibitory effects of costunolide on the telomerase activity in human breast carcinoma cells. Cancer Lett, 227(2):153-62.


Choi JH, Lee KT. (2009). Costunolide-induced apoptosis in human leukemia cells: involvement of c-jun N-terminal kinase activation. Biol Pharm Bull, 32(10):1803-8.


Choi YK, Seo HS, Choi HS, et al. (2012). Induction of Fas-mediated extrinsic apoptosis, p21WAF1-related G2/M cell-cycle arrest and ROS generation by costunolide in estrogen receptor-negative breast cancer cells, MDA-MB-231. Mol Cell Biochem, 363(1-2):119-28. doi: 10.1007/s11010-011-1164-z.


Choi YK, Cho S-G, Woo S-M, et al. (2013). Saussurea lappa Clarke-Derived Costunolide Prevents TNF α-Induced Breast Cancer Cell Migration and Invasion by Inhibiting NF-κ B Activity. Evidence-Based Complementary and Alternative Medicine. doi:10.1155/2013/936257.


Hsu JL, Pan SL, Ho YF, Het al. (2011). Costunolide induces apoptosis through nuclear calcium2+ overload and DNA damage response in human prostate cancer. The Journal of Urology, 185(5):1967-74. doi: 10.1016/j.juro.2010.12.091.


Jeong D, Watari K, Shirouzu T, et al. (2013). Studies on lymphangiogenesis inhibitors from Korean and Japanese crude drugs. Biol Pharm Bull, 36(1):152-7.


Kim EJ, Hong JE, Lim SS, et al. (2012). The hexane extract of Saussurea lappa and its active principle, dehydrocostus lactone, inhibit prostate cancer cell migration. J Med Food, 15(1):24-32. doi: 10.1089/jmf.2011.1735.


Kretschmer N, Rinner B, Stuendl N, et al. (2012). Effect of costunolide and dehydrocostus lactone on cell-cycle, apoptosis, and ABC transporter expression in human soft tissue sarcoma cells. Planta Med, 78(16):1749-56. doi: 10.1055/s-0032-1315385.


Kuo PL, Ni WC, Tsai EM, Hsu YL. (2009). Dehydrocostuslactone disrupts signal transducers and activators of transcription 3 through up-regulation of suppressor of cytokine signaling in breast cancer cells. Mol Cancer Ther, 8(5):1328-39. doi: 10.1158/1535-7163.MCT-08-0914.


Peng ZX, Wang Y, Gu X, Wen YY, Yan C. (2013). A platform for fast screening potential anti-breast cancer compounds in traditional Chinese medicines. Biomed Chromatogr. doi: 10.1002/bmc.2990.


Rasul A, Bao R, Malhi M, et al. (2013). Induction of apoptosis by costunolide in bladder cancer cells is mediated through ROS generation and mitochondrial dysfunction. Molecules, 18(2):1418-33. doi: 10.3390/molecules18021418.


Yang YI, Kim JH, Lee KT, & Choi JH. (2011). Costunolide induces apoptosis in platinum-resistant human ovarian cancer cells by generating reactive oxygen species. Gynecologic Oncology, 123(3), 588-96. doi: 10.1016/j.ygyno.2011.08.031.

Daidzein & S-(-)-equol

Cancer: Breast, prostate

Action: Enhances tamoxifen, radio-sensitizer

Daidzein & Genistein Concentrations; Breast Cancer

A systematic search by Mário L de Lemos (2001) through primary English-language literature on MEDLINE (1966–January 2001), EMBASE (1982–January 2001) and Current Contents (1998–January 2001) found that genistein and daidzein at low concentrations were found to stimulate breast tumor growth in in vitro and in vivo animal studies, and antagonize the anti-tumor effect of tamoxifen in vitro. However, at high concentrations, genistein inhibited tumor growth and enhanced the effect of tamoxifen in vitro.

At concentrations below 10 µmol/L, phytoestrogens can stimulate breast tumor growth and antagonize the anti-tumor effects of tamoxifen, particularly in an environment of low endogenous estrogen. In contrast, phytoestrogens inhibit breast tumor growth and enhance the anti-tumor effects of tamoxifen at concentrations above 10 µmol/L (de Lemos, 2002; Akaza et al., 2004).

Breast cancer

Daidzein or its major metabolite equol at a dose molar equivalent to tamoxifen [1.0 mg(2.7 µmol)/kg or 10 mg (27 µmol)/kg/day] was treated orally to rats bearing 7,12-dimethylbenz(a)anthracene(DMBA)-induced mammary tumors or ovariectomized athymic nude mice implanted with human MCF-7 breast cancer xenograft and an estrogen pellet. The growth of tumors was monitored for several weeks after the treatment. The cell-cycle and apoptotic stages in mammary tumors collected from rats were analyzed by flow cytometry. Immunohistochemistry analysis was also used to determine the expression of caspase-3.

Oral treatment with daidzein or equol at a human equivalent dose suppressed the growth of both DMBA-induced mammary tumors and human MCF-7 breast cancer xenografts in rodents, the inhibitory activity being superior to that of genistein or tamoxifen. Strong apoptosis induced by daidzein or equol contributes to the anti-tumor potential.

Daidzein and its metabolite equol showed the potential of inhibiting the growth of mammary tumors in rodents. Daidzein or equol could be used as a core structure to design new drugs for breast cancer therapy. Our results indicate that consumption of daidzein may protect against breast cancer (Liu et al., 2012).

Equol Production

S-(-)-equol is a metabolite of the soy isoflavone daidzein and is produced by intestinal bacteria in some, but not in all, humans after soy consumption (Setchell & Clerici, 2010). The ability of S-equol to play a role in the treatment of estrogen or androgen-mediated diseases or disorders was first proposed in 1984 (Setchell et al., 1984). The ability to do so depends on two things: soy and bacteria. First, the soy must contain the soy isoflavone daidzein and the amount may influence equol production. Second, the human must have certain strains of bacteria living within the intestine. Twenty-one different strains of intestinal bacteria cultured from humans have the ability to transform daidzein into S-equol or a related intermediate compound (Setchell & Clerici, 2010).

Several studies indicate that only 25 to 30 percent of the adult population of Western countries produces S-equol after eating soy foods containing isoflavones, (Rowland et al., 2000; Atkinson et al., 2005) significantly lower than the reported 50–60% frequency of equol-producers in adults from Japan, Korea, or China (Song et al., 2006).

Equol Production; Prostate Cancer

Akaza et al. (2004) recently conducted a case-controlled study on those who are able to degrade daidzein, a soybean isoflavone, to equol and those without this ability. The incidence of prostate cancer is known to be lower in residents in Japan. On the other hand, American residents in the United States have a markedly higher incidence of prostate cancer.

The number of subjects was 295 in Japan (133 patients and 162 controls), 122 in Korea (61 patients and 61 controls) and 45 in the United States (24 patients and 21 controls). The percentage of equol producers among patients and controls was 29% and 46% in Japan (P = 0.004) and 30% and 59% in Korea (P = 0.001), respectively. The active isoflavone level was markedly lower and the percentage of equol producers was also lower (17% for patients and 14% for controls) for Americans as compared to the Japanese and Koreans.

These results suggest that the ability to produce equol, or equol itself, is closely related to the lower incidence of prostate cancer. The results also suggest that a diet based on soybean isoflavones will be useful in preventing prostate cancer.

Prostate cancer

The age-adjusted incidence rate of prostate cancer (PCa) has been reported to be lower among Asians than Western populations. A traditional Japanese meal., high in soybean products or isoflavones, may be associated with a decreased risk of PCa. Equol, which is converted from daidzein by human intestinal flora, is biologically more active than any other isoflavone aglycone.

Five out of 6 articles showed significant association of isoflavones with a decreased risk of PCa, and two of them consistently showed that equol-producers carry a significantly reduced risk of PCa. Furthermore, 5 human intestinal bacteria that can convert daidzein into equol were identified in the last 5 years. If equol can reduce risk of PCa, a possible strategy for reducing the risk of PCa may be to increase the proportion of equol-producers by changing the intestinal flora to carry an equol-producing bacterium, with dietary alteration or probiotic technology (Sugiyama et al., 2013).

Equol Enhances Tamoxifen

Charalambous, Pitta, & Constantinou (2013) found that equol (>50  µM) and 4-hydroxy-tamoxifen (4-OHT; >100 nM) significantly reduced the breast cancer MCF-7 cell viability. Furthermore, the combination of equol (100 µM) and 4-OHT (10 µM) induced apoptosis more effectively than each compound alone. Subsequent treatment of MCF-7 cells with the pan-caspase inhibitor Z-VAD-FMK inhibited equol- and 4-OHT-mediated apoptosis, which was accompanied by PARP and α-fodrin cleavage, indicating that apoptosis is mainly caspase-mediated.

Equol may be used therapeutically in combination treatments and clinical studies to enhance tamoxifen's effect by providing additional protection against estrogen-responsive breast cancers.

Radio-sensitizer

Sensitivity of cells to equol, radiation and a combination of both was determined by colonogenic assays. Induction of apoptosis by equol, radiation and the combination of both was also determined by acridine orange/ethidium bromide double staining fluorescence microscopy. DNA strand breaks were assessed by Comet assay.

MTT assay showed that equol (0.1-350 µM) inhibited MDA-MB-231 and T47D cell growth in a time- and dose-dependent manner. Treatment of cells with equol for 72 hours (MDA-MB-231) and 24 hours (T47D) was found to inhibit cell growth with IC50 values of 252 µM and 228 µM, respectively. Furthermore, pre-treatment of cells with 50 µM equol for 72 hours (MDA-MB-231) and 24 hours (T47D) sensitized the cells to irradiation. Equol was also found to enhance radiation-induced apoptosis. Comet assay results showed that the radio-sensitizing effect of equol was accompanied by increased radiation-induced DNA damage.

These results suggest for the first time that equol can be considered as a radio-sensitizing agent and its effects may be due to increasing cell death following irradiation, increasing the remaining radiation-induced DNA damage and thus reducing the surviving fraction of irradiated cells (Taghizadeh et al., 2013).

References

Akaza H, Miyanaga N, Takashima N, Naito S, et al. (2004). Comparisons of percent equol producers between prostate cancer patients and controls: case-controlled studies of isoflavones in Japanese, Korean and American residents. Japanese Journal of Clinical Oncology, 34(2): 86–9.


Atkinson, C., Frankenfeld, C.L., Lampe, J.W. (2005). Gut bacterial metabolism of the soy isoflavone daidzein: exploring the relevance to human health. Experimental Biology and Medicine (Maywood, N.J.), 230(3):155–70.


Charalambous C, Pitta CA, Constantinou AI. (2013). Equol enhances tamoxifen's anti-tumor activity by induction of caspase-mediated apoptosis in MCF-7 breast cancer cells. BMC Cancer, 13:238. doi: 10.1186/1471-2407-13-238.


de Lemos ML. (2001). Effects of soy phytoestrogens genistein and daidzein on breast cancer growth. Ann Pharmacother, 35(9):1118-21.


de Lemos ML. (2002). Safety Issues of Soy Phytoestrogens in Breast Cancer Patients. JCO, 20(13):3040-3042.


Liu X, Suzuki N, Santosh Laxmi YR, Okamoto Y, Shibutani S. (2012). Anti-breast cancer potential of daidzein in rodents. Life Sci, 91(11-12):415-9.


Rowland IR, Wiseman H, Sanders TA, Adlercreutz H, Bowey EA. (2000). Interindividual variation in metabolism of soy isoflavones and lignans: influence of habitual diet on equol production by the gut microflora. Nutrition and Cancer, 36(1):27–32. doi:10.1207/S15327914NC3601_5.


Setchell KD, Borriello SP, Hulme P, Kirk DN, Axelson M. (1984). Nonsteroidal estrogens of dietary origin: possible roles in hormone-dependent disease. The American Journal of Clinical Nutrition, 40(3):569–78.


Setchell KD, Clerici C. (2010). Equol: history, chemistry, and formation. The Journal of Nutrition, 140 (7): 1355S–62S. doi:10.3945/jn.109.119776.


Song KB, Atkinson C, Frankenfeld CL, Jokela T, et al. (2006). Prevalence of daidzein-metabolizing phenotypes differs between Caucasian and Korean American women and girls. The Journal of Nutrition, 136(5):1347–51.


Sugiyama Y, Masumori N, Fukuta F, et al. (2013). Influence of isoflavone intake and equol-producing intestinal flora on prostate cancer risk. Asian Pac J Cancer Prev, 14(1):1-4.


Taghizadeh B, Ghavami L, Nikoofar A, Goliaei B. (2013). Equol as a potent radiosensitizer in estrogen receptor-positive and -negative human breast cancer cell lines. Breast Cancer.