Category Archives: anti-tumor

Homoharringtonine/Omacetaxine

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

Action: Induces apoptosis, anti-tumor activity

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

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

Leukemia

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

Acute Myeloid Leukemia (AML)

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

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

Leukemia; Telomerase

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

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

Chronic Myeloid Leukemia (CML)

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

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

Myelodysplastic Syndrome (MDS)

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

References

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


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


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


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


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


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

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.

Hedyotis Diffusa Extract

Cancer: Colon

Action: CYP3A4 induction, inhibits angiogenesis

Hedyotis diffusa is a herb native to East Asia, particularly China, Japan, and Nepal.

Inhibition of tumor angiogenesis has become an attractive target of anti-cancer chemotherapy. However, drug resistance and cytotoxicity against non-tumor-associated endothelial cells limit the long-term use and the therapeutic effectiveness of angiogenesis inhibitors, thus increasing the necessity for the development of multi-target agents with minimal side effects. Hedyotis Diffusa Willd (EEHDW) has long been used as an important component in several TCM formulas to treat various types of cancer.

Inhibits Angiogenesis

The angiogenic effects of the ethanol extract of EEHDW were investigated, in order to find a molecular mechanism for its anti-cancer activity. It was found that EEHDW inhibited angiogenesis in vivo in chick embryo chorioallantoic membrane (CAM). In addition, EEHDW dose- and time-dependently inhibited the proliferation of human umbilical vein endothelial cells (HUVEC) by blocking the cell-cycle G1 to S progression.

Moreover, EEHDW inhibited the migration and tube formation of HUVECs. Furthermore, EEHDW treatment down-regulated the mRNA and protein expression levels of VEGF-A in HT-29 human colon carcinoma cells and HUVECs. These findings suggest that inhibiting tumor angiogenesis is one of the mechanisms by which EEHDW is involved in cancer therapy (Lin et al., 2011).

Colorectal Cancer

Hedyotis diffusa Willd has been used as a major component in several Chinese medicine formulas for the clinical treatment of colorectal cancer (CRC). The ethanol extract of Hedyotis diffusa Willd (EEHDW) reduced tumor volume and tumor weight, and suppressed STAT3 phosphorylation in tumor tissues, which in turn resulted in the promotion of cancer cell apoptosis and inhibition of proliferation. Moreover, EEHDW treatment altered the expression pattern of several important target genes of the STAT3 signaling pathway, i.e., decreased expression of Cyclin D1, CDK4 and Bcl-2 as well as up-regulated p21 and Bax (Cai et al., 2012).

EEHDW reduced HT-29 cell viability and survival in a dose- and time-dependent manner. Lin et al. (2012) observed that EEHDW treatment blocked the cell-cycle, preventing G1 to S progression, and reduced mRNA expression of pro-proliferative PCNA, Cyclin D1 and CDK4, but increased that of anti-proliferative p21 (Lin et al., 2012).

Recently, Lin et al. (2013) reported that HDW could inhibit colorectal cancer growth in vivo and in vitro via suppression of the STAT3 pathway. EEHDW could significantly reduce intratumoral microvessel density (MVD), indicating its activity of anti-tumor angiogenesis in vivo. EEHDW suppressed the activation of SHH signaling in CRC xenograft tumors since it significantly decreased the expression of key mediators of SHH pathway. EEHDW treatment inhibited the expression of the critical SHH signaling target gene VEGF-A as well as its specific receptor VEGFR2 (Lin et al., 2013).

CYP3A4 Induction

Patients are warned against the concomitant use of Oldenlandia diffusa and Rehmannia glutinosa, which could result in induction of CYP3A4, leading to a reduced efficacy of drugs that are CYP3A4 substrates and have a narrow therapeutic window (Lau et al., 2013).

References

Cai Q, Lin J, Wei L, Zhang L, et al. (2012). Hedyotis diffusa Willd Inhibits Colorectal Cancer Growth in Vivo via Inhibition of STAT3 Signaling Pathway. Int J Mol Sci, 13(5):6117-28. doi: 10.3390/ijms13056117.


Lau C, Mooiman KD, Maas-Bakker RF, et al. (2013). Effect of Chinese herbs on CYP3A4 activity and expression in vitro. J Ethnopharmacol, 149(2):543-9. doi: 10.1016/j.jep.2013.07.014.


Lin J, Wei L, Xu W, et al. (2011). Effect of Hedyotis Diffusa Willd extract on tumor angiogenesis. Mol Med Report, 4(6):1283-8. doi: 10.3892/mmr.2011.577.


Lin M, Lin J, Wei L, et al. (2012). Hedyotis diffusa Willd extract inhibits HT-29 cell proliferation via cell-cycle arrest. Exp Ther Med, 4(2):307-310.


Lin J, Wei L, Shen A, et al. (2013). Hedyotis diffusa Willd extract suppresses Sonic hedgehog signaling leading to the inhibition of colorectal cancer angiogenesis. Int J Oncol, 42(2):651-6. doi: 10.3892/ijo.2012.1753.

Glycyrrhiza Uralensis: Glycyrrhizin, Isoliquiritigenin

Cancer:
Cervical., breast, stomach, liver, hepatoma, prostate

Action: Induces apoptosis

The active components of Glycyrrhiza uralensis include the total flavones extracted from Chinese licorice, Glycyrrhiza uralensis Fisch.

Stomach Cancer, Hepatoma, Breast Cancer, Cervical Cancer

The anti-proliferation effect of glycyrrhizhin and total flavones extracted from Chinese licorice, Glycyrrhiza uralensis Fisch, on four kinds of human cancer cells (cervix tumor cell; Hela, breast tumor cell; Bcap-37, stomach tumor cell; MGC-803 and hepatoma cell; Bel-7404) were studied. MTT showed that the anti-proliferation effect of glycyrrhizin was concentration-dependent; higher concentration of glycyrrhizin (1000µg/ml) had obvious anti-tumor effect; within certain concentrations of (200~1000µg/ml), inhibitory effect of total flavones was also concentration dependent; the lower concentration (200µg/ml) was of the highest inhibitory effect: its inhibiting rates on Bcap-37, Hela, Bel-7404, MGC-803 were 79.55%, 79.98%, 67.91% and 37.86% respectively.

Both glycyrrhizin and total flavones have stronger apoptosis-inducing effects on the four kinds of tumor cells (Ma et al., 2008).

Prostate Cancer

Kanazawa et al. (2003) investigated the anti-tumor effect of isoliquiritigenin on prostate cancer in vitro. DU145 and LNCaP prostate cancer cell lines were used as targets. The effects of isoliquiritigenin were examined on cell proliferation, cell-cycle regulation and cell-cycle-regulating gene expression. Further, they investigated the effects of isoliquiritigenin on the GADD153 mRNA and protein expression, and promoter activity. Isoliquiritigenin significantly inhibited the proliferation of prostate cancer cell lines in a dose-dependent and time-dependent manner. These findings suggest that isoliquiritigenin is a candidate agent for the treatment of prostate cancer and GADD153 may play an important role in isoliquiritigenin-induced cell-cycle arrest and cell growth inhibition.

References

Kanazawa M, Satomi Y, Mizutani Y, et al. (2003). Isoliquiritigenin inhibits the growth of prostate cancer. Eur Urol. 43(5):580-6.


Ma M, Zhou X-l, Hu Y-l, et al. (2008). Lishizhen Medicine and Materia Medica Research. doi: CNKI:SUN:SZGY.0.2008-01-006

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.

Gentianaceae

Cancer: Prostate, breast, lung, pancreatic

Action: Causes cell-cycle arrest

Gentianaceae is a naturally occurring alkaloid isolated from Sophora flavescens (Aiton).

Prostate Cancer; AR-

Gentianaceae has shown anti-proliferative properties in a number of types of cancer, including breast, gastric, lung and pancreatic tumors. Gentianaceae was also found to promote apoptosis and inhibit invasion of cancer cells.

The anti-tumor effects of gentianaceae were evaluated on androgen-independent PC-3 prostate cancer cells. The effects of gentianaceae on cell-cycle progression and apoptosis of PC-3 cells were tested. Gentianaceae-treated PC-3 cells underwent G0/G1 cell-cycle arrest. There was a significant reduction in the number of S phase and G2/M phase cells in the treated group when compared to untreated cells.

There was also an increase in the number of necrotic cells in the gentianaceae-treated group when compared to untreated cells. Gentianaceae treatment resulted in increased levels of caspase-3 and Bax and decreased levels of Bcl-2. The data suggest that gentianaceae inhibits the proliferation of androgen-independent prostate cancer cells by causing G0/G1 cell-cycle arrest and promoting apoptosis. Gentianaceae-induced apoptosis was mediated by down-regulation of Bcl-2/Bax ratios and up-regulation of caspase-3 levels (Zhang et al., 2012).

Reference

Zhang P, Wang Z, Chong T, Ji Z. (2012). Matrine inhibits proliferation and induces apoptosis of the androgen “American Typewriter”; “American Typewriter”;‑ independent prostate cancer cell line PC-3. Mol Med Report, 5(3):783-7. doi: 10.3892/mmr.2011.701.

Geniposide –Penta-acetyl Geniposide (Ac)5GP

Cancers:
Glioma, melanoma, liver, hepatocarcinogenesis, hepatoma, prostate, cervical

Action: Cytostatic, induces apoptosis

Gardenia, the fruit of Gardenia jasminoides Ellis, has been widely used to treat liver and gall bladder disorders in Chinese medicine. It has been shown recently that geniposide, the main ingredient of Gardenia fructus , exhibits anti-tumor effect.

Hepatocarcinogenesis, Glioma

It has been demonstrated that (Ac)5GP plays more potent roles than geniposide in chemoprevention. (Ac)5GP decreased DNA damage and hepatocarcinogenesis, induced by aflatoxin B1 (AFB1), by activating the phase II enzymes glutathione S-transferase (GST) and GSH peroxidase (GSH-Px). It reduced the growth and development of inoculated C6 glioma cells, especially in pre-treated rats. In addition to the preventive effect, (Ac)5GP exerts its actions on apoptosis and growth arrest.

Treatment of (Ac)5GP caused DNA fragmentation of glioma cells. (Ac)5GP induced sub- G1 peak through the activation of apoptotic cascades PKCdelta/JNK/Fas/caspase8 and caspase 3. It arrested the cell-cycle at G0/ G1 by inducing the expression of p21, thus suppressing the cyclin D1/cdk4 complex formation and the phosphorylation of E2F.

Data from in vivo experiments indicated that (Ac)5GP is not harmful to the liver, heart and kidney. (Ac)5GP is strongly suggested to be an anti-tumor agent for development in the future (Peng, Huang, & Wang, 2005).

Induces Apoptosis

Previous studies have demonstrated the apoptotic cascades protein kinase C (PKC) delta/c-Jun NH2-terminal kinase (JNK)/Fas/caspases induced by penta-acetyl geniposide [(Ac)5GP]. However, the upstream signals mediating PKCdelta activation have not yet been clarified. Ceramide, mainly generated from the degradation of sphingomyelin, was hypothesized upstream above PKCdelta in (Ac)5GP-transduced apoptosis.

After investigation, (Ac)5GP was shown to activate neutral sphingomyelinase (N-SMase) immediately, with its maximum at 15 min. The NGF and p75 enhanced by (Ac)5GP was inhibited when combined with GW4869, the N-SMase inhibitor, indicating NGF/p75 as the downstream signals of N-SMase/ceramide. To evaluate whether N-SMase is involved in (Ac)5GP-transduced apoptotic pathway, cells were treated with (Ac)5GP, alone or combined with GW4869. It was demonstrated that N-SMase inhibition blocked FasL expression and caspase 3 activation. Similarly, p75 antagonist peptide attenuated the FasL/caspase 3 expression. It indicated that N-SMase activation is pivotal in (Ac)5GP-mediated apoptosis.

SMase and NGF/p75 are suggested to mediate upstream above PKCdelta, thus transducing FasL/caspase cascades in (Ac)5GP-induced apoptosis (Peng, Huang, Hsu, & Wang, 2006).

Glioma

Penta-acetyl geniposide [(Ac)(5)GP], an acetylated geniposide product from Gardenia fructus, has been known to have hepato-protective properties and recent studies have revealed its anti-proliferative and apoptotic effect on C6 glioma cells. The anti-metastastic effect of (Ac)(5)GP in the rat neuroblastoma line C6 glioma cells were investigated.

Further (Ac)(5)GP also exerted an inhibitory effect on phosphoinositide 3-kinase (PI3K) protein expression, phosphorylation of extracellular signal-regulated kinases 1 and 2 (ERK1/2) and inhibition of activation of transcription factor nuclear factor kappa B (NF-kappaB), c-Fos, c-Jun.

Findings suggest (Ac)(5)GP is highly likely to be an inhibiting cancer migration agent to be further developed in the future (Huang et al., 2009).

Melanoma

A new iridoid glycoside, 10-O-(4'-O-methylsuccinoyl) geniposide, and two new pyronane glycosides, jasminosides Q and R, along with nine known iridoid glycosides, and two known pyronane glycosides, were isolated from a MeOH extract of Gardeniae Fructus, the dried ripe fruit of Gardenia jasminoides (Rubiaceae).

The structures of new compounds were elucidated on the basis of extensive spectroscopic analyzes and comparison with literature. Upon evaluation of these compounds on the melanogenesis in B16 melanoma cells induced with α-melanocyte-stimulating hormone (α-MSH), three compounds, i.e., 6-O-p-coumaroylgeniposide (3), 7, and 6'-O-sinapoyljasminoside (12), exhibited inhibitory effects with 21.6-41.0 and 37.5-47.7% reduction of melanin content at 30 and 50 µM, respectively, with almost no toxicity to the cells (83.7-106.1% of cell viability at 50 µM) (Akisha et al., 2012).

Hepatoma, Prostate Cancer, Cervical Cancer

Genipin is a metabolite of geniposide isolated from an extract of Gardenia fructus. Some observations suggested that genipin could induce cell apoptosis in hepatoma cells and PC3 human prostate cancer cells. Genipin could remarkably induce cytotoxicity in HeLa cells and inhibit its proliferation. Induction of the apoptosis by genipin was confirmed by analysis of DNA fragmentation and induction of sub-G(1) peak through flow cytometry.

The results also showed that genipin-treated HeLa cells cycle was arrested at G(1) phase. Western blot analysis revealed that the phosphorylated c-Jun NH(2)-terminal kinase (JNK) protein, phospho-Jun protein, p53 protein and bax protein significantly increased in a dose-dependent manner after treatment of genipin for 24 hours; the activation of JNK may result in the increase of the p53 protein level; the increase of the p53 protein led to the accumulation of bax protein; and bax protein further induced cell apoptotic death eventually (Cao et al., 2010).

References

Akihisa T, Watanabe K, Yamamoto A, et al. (2012). Melanogenesis inhibitory activity of monoterpene glycosides from Gardeniae Fructus. Chemistry & Biodiversity, 9(8), 1490-9. doi: 10.1002/cbdv.201200030.


Cao H, Feng Q, Xu W, et al. (2010). Genipin induced apoptosis associated with activation of the c-Jun NH2-terminal kinase and p53 protein in HeLa cells. Biol Pharm Bull, 33(8):1343-8.


Huang HP, Shih YW, Wu CH, et al. (2009). Inhibitory effect of penta-acetyl geniposide on C6 glioma cells metastasis by inhibiting matrix metalloproteinase-2 expression involved in both the PI3K and ERK signaling pathways. Chemico-biological Interactions, 181(1), 8-14. doi: 10.1016/j.cbi.2009.05.009.


Peng CH, Huang CN, Hsu SP, Wang CJ. (2006). Penta-acetyl geniposide induce apoptosis in C6 glioma cells by modulating the activation of neutral sphingomyelinase-induced p75 nerve growth factor receptor and protein kinase Cdelta pathway. Molecular Pharmacology, 70(3), 997-1004.


Peng CH, Huang CN, Wang CJ. (2005). The anti-tumor effect and mechanisms of action of penta-acetyl geniposide. Current Cancer Drug Targets, 5(4), 299-305.

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.

Dauricine

Cancer: Prostate, urinary system, breast, lung

Action: MDR

Lung Cancer

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

Prostate Cancer

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

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

Breast Cancer

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

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

Breast Cancer; MDR

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

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

MDR

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

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

References

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

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

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

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

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

Dandelion Root Extract (Taraxacum)

Cancer:
Pancreatic, Chronic Myelomonocytic Leukemia, leukemia, liver, hepatocellular carcinoma

Action: Induces cytotoxicity, induces apoptosis

Dandelion root is extracted from Taraxacum officinale (F.H. Wigg).

Hepatocellular Carcinoma

Taraxacum officinale (TO) has been frequently used as a remedy for women's diseases (e.g. breast and uterus cancer) and disorders of the liver and gallbladder. Several earlier studies have indicated that TO exhibits anti-tumor properties. TO decreased the cell viability by 26%, and significantly increased the tumor necrosis factor (TNF)-alpha and interleukin (IL)-1alpha production compared with media control (about 1.6-fold for TNF-alpha, and 2.4-fold for IL-1alpha, P < 0.05). Also, TO strongly induced apoptosis of Hep G2 cells as determined by flow cytometry. Increased amounts of TNF-alpha and IL-1alpha contributed to TO-induced apoptosis. Anti-TNF-alpha and IL-1alpha antibodies almost abolished it. These results suggest that TO induces cytotoxicity through TNF-alpha and IL-1alpha secretion in Hep G2 cells (Koo et al., 2004).

Pancreatic Cancer

The efficacy of dandelion root extract (DRE) in inducing apoptosis and autophagy in aggressive and resistant pancreatic cancer cells, known to have a high rate of mortality, have been investigated. The effect of DRE was evaluated using WST-1 (4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate) assay.

This extract induces selective apoptosis in a dose- and time-dependent manner. Dandelion root extract caused the collapse of the mitochondrial membrane potential., leading to prodeath autophagy. Normal human fibroblasts were resistant at similar doses. It was demonstrated that DRE has the potential to induce apoptosis and autophagy in human pancreatic cancer cells with no significant effect on noncancerous cells. This will provide a basis on which further research in cancer treatment through DRE can be executed (Ovadje et al., 2012a).

Chronic Myelomonocytic Leukemia

Chronic myelomonocytic leukemia (CMML) is a heterogeneous disease that is not only hard to diagnose and classify, but is also highly resistant to treatment. Available forms of therapy for this disease have not shown significant effects and patients rapidly develop resistance early on in therapy. These factors lead to the very poor prognosis observed with CMML patients, with median survival duration between 12 and 24 months after diagnosis. This study is therefore centered around evaluating the selective efficacy of a natural extract from dandelion roots, in inducing programmed cell death in aggressive and resistant CMML cell lines.

The results from this study indicate that Dandelion Root Extract (DRE) is able to efficiently and selectively induce apoptosis and autophagy in these cell lines in a dose and time-dependent manner, with no significant toxicity on non-cancerous peripheral blood mononuclear cells. More importantly, we observed early activation of initiator caspase-8, which led to mitochondrial destabilization and the induction of autophagy, suggesting that DRE acts through the extrinsic pathway of apoptosis (Ovadje et al., 2012b).

Leukemia

A study by Ovadje et al. (2011) determined the anti-cancer activity of dandelion root extract (DRE) against human leukemia, and evaluated the specificity and mechanism of DRE-induced apoptosis. Aqueous DRE contains components that act to induce apoptosis selectively in cultured leukemia cells, emphasizing the importance of this traditional medicine and thus presents a potential novel non-toxic alternative to conventional leukemia therapy.

References

Koo HN, Hong SH, Song BK, et al. (2004). Taraxacum officinale induces cytotoxicity through TNF-alpha and IL-1alpha secretion in Hep G2 cells. Life Sci, 74(9):1149-57.


Ovadje P, Chatterjee S, Griffin C, et al. (2011). Selective induction of apoptosis through activation of caspase-8 in human leukemia cells (Jurkat) by dandelion root extract. J Ethnopharmacol, 133(1):86-91. doi: 10.1016/j.jep.2010.09.005.


Ovadje P, Chochkeh M, Akbari-Asl P, Hamm C, Pandey S. (2012). Selective Induction of Apoptosis and Autophagy Through Treatment With Dandelion Root Extract in Human Pancreatic Cancer Cells. Pancreas, 41(7),1039-47. doi: 10.1097/MPA.0b013e31824b22a2.


Ovadje P, Hamm C, Pandey S. b (2012). Efficient induction of extrinsic cell death by dandelion root extract in human chronic myelomonocytic leukemia (CMML) cells. PLoS One. 2012;7(2):e30604. doi: 10.1371/journal.pone.0030604.

Cucurbitacin D (CuD) (See also Trichosanthin)

Cancer: Hepatocellular carcinoma, pancreatic, breast

Action: Apoptosis

Breast Cancer

Cucurbitacin D (CuD) isolated from Trichosanthes kirilowii induces apoptosis in several cancer cells. Constitutive signal transducer and activator of transcription 3 (STAT3), which is an oncogenic transcription factor, is often observed in many human malignant tumors, including breast cancer. Kim et al. (2013) tested whether Trichosanthes kirilowii ethanol extract (TKE) or CuD suppresses cell growth and induces apoptosis through inhibition of STAT3 activity in breast cancer cells.

They found that both TKE and CuD suppressed proliferation and induced apoptosis and G2/M cell-cycle arrest in MDA-MB-231 breast cancer cells by inhibiting STAT3 phosphorylation. In addition, both TKE and CuD inhibited nuclear translocation and transcriptional activity of STAT3. Taken together, our results indicate that TKE and its derived compound, CuD, could be potent therapeutic agents for breast cancer, blocking tumor cell proliferation and inducing apoptosis through suppression of STAT3 activity.

Hepatocellular Carcinoma

Takahashi et al. (2009) found that the anti-tumor components isolated from the extract of trichosanthes (EOT) are cucurbitacin D and dihydrocucurbitacin D, and suggest that cucurbitacin D induces apoptosis through caspase-3 and phosphorylation of JNK in hepatocellular carcinoma cells. These results suggest that cucurbitacin D isolated from Trichosanthes kirilowii could be a valuable candidate for an anti-tumor drug.

Pancreatic Cancer

Dose-response studies showed that the drug inhibited 50% growth of seven pancreatic cancer cell lines at 10−7 mol/L, whereas clonogenic growth was significantly inhibited at 5 × 10−8 mol/L. Cucurbitacin B caused dose- and time-dependent G2-M-phase arrest and apoptosis of pancreatic cancer cells. This was associated with inhibition of activated JAK2, STAT3, and STAT5, increased level of p21WAF1 even in cells with nonfunctional p53, and decrease of expression of cyclin A, cyclin B1, and Bcl-XL with subsequent activation of the caspase cascade.

Cucurbitacin B has profound in vitro and in vivo anti-proliferative effects against human pancreatic cancer cells, and the compound may potentate the anti-proliferative effect of the chemotherapeutic agent gemcitabine. Further clinical studies are necessary to confirm our findings in patients with pancreatic cancer (Thoennissen et al., 2009).

References

Kim SR, Seo HS, Choi H-S, et al. (2013). Trichosanthes kirilowii Ethanol Extract and Cucurbitacin D Inhibit Cell Growth and Induce Apoptosis through Inhibition of STAT3 Activity in Breast Cancer Cells. Evidence-Based Complementary and Alternative Medicine, 2013. http://dx.doi.org/10.1155/2013/975350


Thoennissen NH, Iwanski GB, Doan NB, et al. (2009). Cucurbitacin B Induces Apoptosis by Inhibition of the JAK/STAT Pathway and Potentiates Anti-proliferative Effects of Gemcitabine on Pancreatic Cancer Cells.   Cancer Res, 69; 5876 doi: 10.1158/0008-5472.CAN-09-0536


Takahashi N, Yoshida Y, Sugiura T, et al. (2009). Cucurbitacin D isolated from Trichosanthes kirilowii induces apoptosis in human hepatocellular carcinoma cells in vitro. International Immunopharmacology, 9(4):508–513.

Cryptotanshinone (See also Tanshinone)

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

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

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

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

Anti-proliferative Agent

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

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

Anti-inflammatory; COX-2, PGE2

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

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

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

Prostate Cancer

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

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

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

Prostate Cancer; Androgen Receptor Positive

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

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

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

Breast Cancer, Cervical Cancer, Leukemia, Hepatocellular Carcinoma

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

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

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

Breast Cancer

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

Hepato-protective Effect

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

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

References

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

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

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

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

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

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

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

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

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

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

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

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

Corosolic acid

Cancer:
Myeloid leukemia, cervical., glioblastoma, gastric, sarcoma

Action: Immunosuppressive activity

Corosolic Acid is isolated from Lagerstroemia speciosa [(L.) Pers.] and Crataegus pinnatifida var. psilosa (C. K. Schneider).

Sarcoma; Immunosuppressive Activity

The results from an in vivo study showed that Corosolic acid (CA) administration did not suppress the tumor proliferation index, but significantly impaired subcutaneous tumor development and lung metastasis.

CA administration inhibited signal transducer and activator of transcription-3 (Stat3) activation and increased in the number of infiltrating lymphocytes in tumor tissues. Ex vivo analysis demonstrated that a significant immunosuppressive effect of MDSC in tumor-bearing mice was abrogated and the mRNA expressions of cyclooxygenase-2 and CCL2 in MDSC were significantly decreased by CA administration.

Furthermore, CA enhanced the anti-tumor effects of adriamycin and cisplatin in vitro. Since Stat3 is associated with tumor progression not only in osteosarcoma, but also in other malignant tumors, these findings indicate that CA might be widely useful in anti-cancer therapy by targeting the immunosuppressive activity of MDSC and through its synergistic effects with anti-cancer agents (Horlad et al., 2013).

Cervical Cancer

Xu et al. (2009) investigated the response of human cervix adenocarcinoma HeLa cells to Corosolic acid (CRA) treatment. These results showed that CRA significantly inhibited cell viability in both a dose- and a time-dependent manner. CRA treatment induced S cell-cycle arrest and caused apoptotic death in HeLa cells. It was found that CRA increased in Bax/Bcl-2 ratios by up-regulating Bax expression, disrupted mitochondrial membrane potential and triggered the release of cytochrome c from mitochondria into the cytoplasm.

These results, taken together, indicate CRA could have strong potentials for clinical application in treating human cervix adenocarcinoma and improving cancer chemotherapy.

Glioblastoma

Tumor-associated macrophages (TAMs) of M2 phenotype promote tumor proliferation and are associated with a poor prognosis in patients with glioblastoma.

The natural compounds possessing inhibitory effects on M2 polarisation in human monocyte-derived macrophages were investigated. Among 130 purified natural compounds examined, corosolic acid significantly inhibited the expression of CD163, one of the phenotype markers of M2 macrophages, as well as suppressed the secretion of IL-10, one of the anti-inflammatory cytokines preferentially produced by M2 macrophages, thus suggesting that corosolic acid suppresses M2 polarisation of macrophages.

Furthermore, corosolic acid inhibited the proliferation of glioblastoma cells, U373 and T98G, and the activation of Signal transducer and activator of transcription-3 (STAT3) and Nuclear Factor-kappa B (NF-κB), in both human macrophages and glioblastoma cells. These results indicate that corosolic acid suppresses the M2 polarisation of macrophages and tumor cell proliferation by inhibiting both STAT3 and NF-κB activation. Therefore, corosolic acid may be a new tool for tumor prevention and therapy (Fujiwara et al., 2010).

Gastric Cancer

Corosolic acid (CRA) suppresses HER2 expression, which in turn promotes cell-cycle arrest and apoptotic cell death of gastric cancer cells, providing a rationale for future clinical trials of CRA in the treatment of HER2-positive gastric cancers. CRA combined with adriamycin and 5-fluorouracil enhanced this growth inhibition, but not with docetaxel and paclitaxel (Lee et al., 2010).

Leukemia

Corosolic acid displayed about the same potent cytotoxic activity as ursolic acid against several human cancer cell lines. In addition, the compound displayed antagonistic activity against the phorbol ester-induced morphological modification of K-562 leukemic cells, indicating the suppression of protein kinase C (PKC) activity by the cytotoxic compound (Ahn et al., 1998).

References

Ahn KS, Hahm MS, Park EJ, Lee HK, Kim IH. (1998). Corosolic acid isolated from the fruit of Crataegus pinnatifida var. psilosa is a protein kinase C inhibitor as well as a cytotoxic agent. Planta Med, 64(5):468-70.


Fujiwara Y, Komohara Y, Ikeda T, Takeya M. (2010). Corosolic acid inhibits glioblastoma cell proliferation by suppressing the activation of signal transducer and activator of transcription-3 and nuclear factor-kappa B in tumor cells and tumor-associated macrophages. Cancer Science. doi: 10.1111/j.1349-7006.2010.01772.x


Horlad H, Fujiwara Y, Takemura K, et al. (2013). Corosolic acid impairs tumor development and lung metastasis by inhibiting the immunosuppressive activity of myeloid-derived suppressor cells. Molecular Nutrition & Food Research, 57(6):1046-1054. doi: 10.1002/mnfr.201200610


Lee MS, Cha EY, Thuong PT, et al. (2010). Down-regulation of human epidermal growth factor receptor 2/neu oncogene by corosolic acid induces cell-cycle arrest and apoptosis in NCI-N87 human gastric cancer cells. Biol Pharm Bull, 33(6):931-7.


Xu YF, Ge RL, Du J, et al. (2009). Corosolic acid induces apoptosis through mitochondrial pathway and caspases activation in human cervix adenocarcinoma HeLa cells. Cancer Letters, 284(2):229-237. doi:10.1016/j.canlet.2009.04.028.

Corilagin

Cancer: Ovarian, hepatocellular carcinoma

Action: Radio-protective

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

Ovarian Cancer

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

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

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

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

Hepatocellular Carcinoma

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

Radio-protective

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

References

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


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


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

Cinobufacini

Cancers: Liver, lung

Action: Chemo-sensitizer, chemotherapy support, cytostatic

Hepatic Cancer

Cinobufacini injection significantly inhibits proliferation, heterogeneous adhesion and invasiveness of hepG-2 cells co-cultured with HLEC in dose-dependent ways (all P0.05). Cinobufacini injection can inhibit the capability of proliferation, invasiveness and heterogeneous adhesion of HepG-2 cells, which might contribute to the inhibiting mechanisms of Cinobufacini injection on tumor metastasis (Fu, Gao, Tian, Chen, & Cui, 2013).

Human Lymphatic Endothelial Cells

Cinobufacini injection is a traditional anti-tumor drug. However, its mechanism of action is still unclear. The effects of Cinobufacini injection on proliferation, migration and tubulin formation of human lymphatic endothelial cells (HLEC) was investigated.

Cell growth curve was used to observe the effect of Cinobufacini injection on the proliferation of HLEC; migration assay was used to observe the effect of Cinobufacini injection on the migration of HLEC; Matrigel assay was used to observe the effect of Cinobufacini injection on the tubulin formation of HLEC; Western blot was used to analyze the expression of VEGFR-3 and HGF in HLEC.

Cinobufacini injection significantly inhibits HLEC proliferation, migration, and tubulin formation. The down-regulation of VEGFR-3 and HGF may contribute to the inhibitory effect of Cinobufacini injection on HLEC (Gao, Chen, Xiu, Fu, & Cui, 2013).

NSCLC

The efficacy and safety of Cinobufacini injection, combined with chemotherapy, as a treatment for advanced non-small-cell lung cancer (NSCLC) was investigated. Based on existing clinical information, a search of databases, such as MEDLINEe (1966-2011), Cochrane Library (2011, Issue 11), CNKI (1978-2011), VIP (1989-2011), Wanfang Data (1988-2011), CBMdisc (1978-2011) was done.

Cinobufacini, combined with chemotherapy, is suitable for advanced NSCLC by improving the response rate, increasing Karnofsky score, gaining weight and reducing major side-effects (Tu, Yin, & He, 2012).

Liver Cancer

Seventy-eight patients with moderate and advanced primary liver cancer were randomly divided. The treatment group (n=38) was treated by Cinobufacini injection combined with transcatheter arterial chemoembolization (TACE), and the control group (n=40), was treated by TACE only.

Quality of life of patients in the treatment group was significantly higher than that in control group. The 12 months survival rate of the treatment group was significantly higher than that of the control group. Cinobufacini injection, combined with TACE, can decrease TACE-induced liver damage, prolong survival time, and improve body immunity (Ke, Lu, & Li, 2011).

Cinobufacini injection significantly inhibited HepG-2 cells proliferation in a dose- and time- dependent manner. FCM analysis showed Cinobufacini injection induced cell-cycle arrest at the S phase. RT-PCR assay showed Cinobufacini injection down-regulated Cyclin A, and CDK2 expression at mRNA levels. Quantitative colorimetric assay showed Cinobufacini injection deceased Cyclin A/CDK2 activity in HepG-2 cells.

Cinobufacini injection can inhibit human hepatoma HepG-2 cells growth, induce cell apoptosis and induce cell-cycle arrest at the S phase. Its mechanism might be partly related to the down-regulation of Cyclin A, CDK2 mRNA expression, and inhibition of Cyclin A/CDK2 activity (Sun, Lu, Liang, & Cui, 2011).

References

Fu HY, Gao S, Tian LL, Chen XY, Cui XN. (2013). Effect of Cinobufacini injection on proliferation and invasiveness of human hepatoma HepG-2 cells co-cultured with human lymphatic endothelial cells. The Chinese Journal of Clinical Pharmacology, 29(3), 199-201.


Gao S, Chen XY, Fu HY, Cui XZ. (2013). The effect of Cinobufacini injection on proliferation and tube-like structure formation of human lymphatic endothelial cells. China Oncology, 23(1), 36-41.


Ke J, Lu K, Li Y. (2011). Clinical observation of patients with primary liver cancer treated by Cinobufagin Injection combined with transcatheter arterial chemoembolization. Chinese Journal of Clinical Hepatology,


Sun Y, Lu XX, Liang XM, Cui XN. (2011). Impact of Cinobufacini injection on proliferation and cell-cycle of human hepatoma HepG-2 cells. The Chinese-German Journal of Clinical Oncology, 10(6), 321-324.


Tu C, Yin J, He J. (2012). Meta-analysis of Cinobufacini injection plus chemotherapy in the treatment of non-small-cell lung cancer. Anti-tumor Pharmacy, 2(1), 67-72.

Bezielle

Cancer: Metastatic and ER-negative Breast

Action: Anti-cancer

Breast Cancer

Bezielle is an orally administered aqueous extract of Scutellaria barbata for treatment of advanced and metastatic breast cancer. Phase I trials showed promising tolerability and efficacy. In our study, we used a combined proteomic-metabolomic approach to investigate the molecular pathways affected by Bezielle in ER-positive BT474 and ER-negative SKBR3 cell lines. Bezielle's ability to induce oxidative stress was associated with the changes in expression of redox potential maintaining enzymes: glutathione- and thioredoxin-related proteins and peroxiredoxins. In regards to cell metabolism, decreased expression of α-enolase was associated with a reduction of de novo (13) C-lactate formation.

By inhibiting glucose metabolism, cells reacted by lowering the expression of glucose transporters and resulting in decreased intracellular glucose concentration. Decreased expression of fatty acid synthase and reduced concentration of phosphocholine indicated considerable changes in phospholipid metabolism. Ultimately, by inhibiting the major energy-producing pathways, Bezielle caused depletion of ATP and NAD(H). Both cell lines were responsive, thus suggesting that Bezielle has the potential to be effective against ER-negative breast cancers. In conclusion, Bezielle's cytotoxicity toward cancer cells is primarily based on inhibition of metabolic pathways that are preferentially activated in tumor cells thus explaining its specificity for cancer cells (Klawitter et al., 2011).

Anti-cancer

Chen et al. (2012) found that the cytotoxic activity of the Bezielle extract in vitro co-purified with a defined fraction containing multiple flavonoids. They isolated several of these Bezielle flavonoids, and examined their possible roles in the selective anti-tumor cytotoxicity of Bezielle. The results support the hypothesis that a major Scutellaria flavonoid, scutellarein, possesses many if not all of the biologically relevant properties of the total extract. Like Bezielle, scutellarein induced increasing levels of ROS of mitochondrial origin, progressive DNA damage, protein oxidation, depletion of reduced glutathione and ATP, and suppression of both OXPHOS and glycolysis.

Like Bezielle, scutellarein was selectively cytotoxic towards cancer cells.

Carthamidin, a flavonone found in Bezielle, also induced DNA damage and oxidative cell death. Two well known plant flavonoids, apigenin and luteolin, had limited and not selective cytotoxicity that did not depend on their pro-oxidant activities. We also provide evidence that the cytotoxicity of scutellarein was increased when other Bezielle flavonoids, not necessarily highly cytotoxic or selective on their own, were present. This indicates that the activity of total Bezielle extract might depend on a combination of several different compounds present within it (Chen et al., 2012).

References

Chen V, Staub RE, Baggett S, et al. (2012). Identification and analysis of the active phytochemicals from the anti-cancer botanical extract Bezielle. PLoS One, 7(1):e30107. doi: 10.1371/journal.pone.0030107.


Klawitter J, Klawitter J, Gurshtein J, et al. (2011). Bezielle (BZL101)-induced oxidative stress damage followed by redistribution of metabolic fluxes in breast cancer cells: a combined proteomic and metabolomic study. Int J Cancer. 129(12):2945-57. doi: 10.1002/ijc.25965.

Betulin and Betulinic acid

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

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

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

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

Anti-cancer, Induces Apoptosis

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

Lung Cancer

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

Esophageal Squamous Carcinoma

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

Leukemia

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

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

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

Multiple Myeloma

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

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

Anti-angiogenic Effects, Colorectal Cancer

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

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

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

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

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

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

Cervical Carcinoma

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

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

Anti-oxidant, Cytotoxic and Immunomodifying Activities

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

Pancreatic Cancer

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

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

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

Multiple Myeloma, Prostate Cancer

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

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

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

Melanoma

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

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

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

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

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

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

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

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

Glioma

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

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

Head and Neck Carcinoma

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

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

References

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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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


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

Berbamine

Cancer: Breast, leukemia, liver, neutropenia

Action: Anti-metastatic, chemo-sensitizer

Breast Cancer, Leukemia

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

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

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

MDR, Leukemia stem cells

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

Liver Cancer, Leukemia

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

Chronic Myeloid Leukemia, Leukopenia

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

References

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


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


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


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


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

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.

Aconitum polysaccharide ACP-a1

Aconitum polysaccharide ACP-a1

Cancer: Liver, leukemia

Action: Chemo-sensitizer

Hepatoma

A polysaccharide (ACP-a1) was successfully purified and identified from the roots of Aconitum coreanum (Lvl.)

The effects of ACP-a1 on the tumor growth and immune function were assessed in hepatoma H22 bearing mice. Results showed that ACP-a1 significantly inhibited the growth of hepatoma H22 transplanted in mice and prolonged the survival time of H22 tumor-bearing mice. As well, the body weight, peripheral white blood cells (WBC), thymus index and spleen index of H22 tumor-bearing were also improved after ACP-a1 treatment.

Furthermore, ACP-a1 could promote the secretion of serum cytokines in H22 tumor-bearing mice, such as IL-2, TNF-α and IFN-γ. Taken together, these results indicate that ACP-a1 inhibits tumor growth in vivo at least partly via improving immune responses of the host organism, and seems to be safe and effective as a novel agent with immunomodulatory activity for the use of anti-tumor therapy (Li et al., 2013).

Chemo-sensitizer; Liver carcinoma

The monkshood polysaccharide (MPS), aconitum, was studied for its combined synergistic effect, with Adriamycin (ADM), versus Adriamycin alone. Both treatments were delivered via long circulating temperature-sensitive liposome (LTSL) in H22, liver carcinoma, tumor-bearing mice. The synergic action of monkshood polysaccharide (MPS) and adriamycin (ADM) long circulating temperature-sensitive liposome (ALTSL) in targeting therapy for H22 tumor-bearing mice was studied

Outcomes assessed included tumor weight, as an index for anti-tumorigenic effect, as well as survival time. Natural killer cell activity of NK cells was higher in the ALTSL group versus the control, but lower than the MPS + ALTSL group. Lymphocyte transformation in the MPS + ALTSL group was markedly improved (P < 0.01) relative to the ALTSL.

Results of RT-PCR indicated that the expression of IL-2 mRNA and IL-12 mRNA, in lymphocytes, in ALTSL group were significantly higher than those in the control. However, expression of IL-2 mRNA and IL-12 mRNA was much higher in the MPS + ALTSL versus the ALTSL group.

LTSL can increase the anti-tumor effect and decrease the
side-effects, such as cytotoxicity, of ADM. MPS combined with ALTSL can enhance natural killer cell activity and transformation of T cells, creating a synergistic anti-tumorigenic effect (Dong et al., 2006).

Leukemia

Two amide alkaloids, named 3-isopropyl-tetrahydropyrrolo [1,2-a]
pyrimidine-2,4(1H,3H)-dione (1) and 1-acetyl-2,3,6-triisopropyl-tetrahydropyrimidin-4(1H)-one (2), were isolated from the roots of Aconitum taipeicum. These compounds exhibited more significant cell growth-inhibitory activities against human promyelocytic leukemia (HL-60) cells than adriamycin, with the IC(50) of 1.1 ± 0.03 µg/mL and 1.6 ± 0.07 µg/mL respectively. In addition, two compounds showed anti-tumor activities against K562 cells as well (Xu, Guo & Wu, 2010).

References

Dong LF, Zhang YJ, Liu JS, et al. (2006). Anti-tumor effect of monkshood polysaccharide with Adriamycin long circulating temperature-sensitive liposome and its mechanism. Chinese Journal of Cellular and Molecular Immunology, 22(4), 458-462.

Li H, Sun M, Xu J, et al. (2013). Immunological response in H22 transplanted mice undergoing Aconitum coreanum polysaccharide treatment. Int J Biol Macromol, 55:295-300. doi:10.1016/j.ijbiomac.2013.01.011.

Xu Y, Guo ZJ, Wu N. (2010). Two new amide alkaloids with anti-leukaemia activities from Aconitum taipeicum. Fitoterapia, 81(8):1091-3. doi: 10.1016/j.fitote.2010.07.005.