Category Archives: inhibits angiogenesis

angiogenesis, Anti-cancer, Anti-cancer effect, apoptosis, Chapter 7 Isolates and Cancer Research, induces apoptosis, inhibits angiogenesis, p16, p21, PARP, VEGF, VEGF, XIAP

Teng Long Bu Zhong Tang

Cancer: Colon

Action: Induces apoptosis, inhibits angiogenesis

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

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

Reference

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

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

Magnolol

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

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

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

Anti-inflammatory

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

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

Bladder Cancer; Inhibits Angiogenesis

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

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

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

Colon Cancer; Induces Apoptosis

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

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

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

Ovarian Cancer

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

Lung Cancer

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

Prostate Cancer; Anti-metastatic

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

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

Glioblastoma Cancer

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

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

Inhibits Angiogenesis

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

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

References

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


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


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


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


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


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


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


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

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

Indirubin

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

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

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

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

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

Leukemia

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

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

Aryl Hydrocarbon Receptor (AhR) Regulator; Breast Cancer

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

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

Chronic Myelogenous Leukemia (CML)

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

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

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

Lung Cancer

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

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

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

Head and Neck Cancer

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

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

Prostate Cancer; Inhibits Angiogenesis

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

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

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

Acute Myeloid Leukemia

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

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

References

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


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


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


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


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


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


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


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


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

angiogenesis, Anti-cancer, anti-proliferative, anti-tumor, apoptosis, BAX, Bcl-2, CAM, CDK4, Chapter 7 Isolates and Cancer Research, Chemotherapy, Colon Cancer or Colorectal cancer, CYP3A4 induction, G1, inhibits angiogenesis, p21, PCNA, Rectal cancer, S, SHH, STAT3, VEGF, VEGF

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.

Akt, angiogenesis, Anti-cancer, Breast cancer, Chapter 7 Isolates and Cancer Research, ER, ERK1, FAK, Glycyrrhiza glabra, growth-inhibitory, inhibits angiogenesis, inhibits metastasis, MDA-MB-231, metastasis

Glabridin

Cancer: Breast

Action: Inhibits metastasis, inhibits angiogenesis

Glabridin is a novel phytoestrogen isolated from licorice extract (Glycyrrhiza glabra (L.))

Breast Cancer Growth; Estrogen agonist

Glabridin and its derivatives bind to the human ER and have been found to act as an estrogen agonist in the induction of an estrogen response marker, such as CK activity, in vivo, to induce uterus wet weight, and to stimulate human breast cancer cell growth. There is an increasing demand for natural compounds that improve women's health by mimicking the critical benefits of estrogen to the bones and the cardiovascular system but avoiding its deleterious effects on the breast and uterus.

The estrogenic properties of glabridin, the major isoflavan in licorice root, were tested in view of the resemblance of its structure and lipophilicity to those of estradiol. The results indicate that glabridin is a phytoestrogen, binding to the human estrogen receptor and stimulating creatine kinase activity in rat uterus, epiphyseal cartilage, diaphyseal bone, aorta, and left ventricle of the heart. This indicates that isoflavans have estrogen-like activities. Glabridin and its derivatives exhibited varying degrees of estrogen receptor agonism in different tests and demonstrated growth-inhibitory actions on breast cancer cells (Tamir et al., 2000).

Inhibits Metastasis, Inhibits Angiogenesis

Glabridin exhibited effective inhibition of cell metastasis by decreasing cancer cell migration and invasion of metastatic MDA-MB-231 breast cancer cells. In addition, glabridin also blocked human umbilical vein endothelial cells (HUVEC) migration and decreased MDA-MB-231-mediated angiogenesis. Further investigation revealed that the inhibition of cancer angiogenesis by glabridin was also evident in a nude mice model. Blockade of MDA-MB-231 cells and HUVEC migration was associated with an increase of αγβ3 integrin proteosome degradation. Glabridin also decreased the active forms of FAK and Src, and enhanced levels of inactivated phosphorylated Src (Tyr 416), decreasing the interaction of FAK and Src.

Inhibition of the FAK/Src complex by glabridin also blocked AKT and ERK1/2 activation, resulting in reduced activation of RhoA as well as myosin light chain phosphorylation. This study demonstrates that glabridin may be a novel anti-cancer agent for the treatment of breast cancer in three different ways: inhibition of migration, invasion and angiogenesis (Hsu et al., 2011).

References

Hsu YL, Wu LY, Hou MF, et al. (2011). Glabridin, an isoflavan from licorice root, inhibits migration, invasion and angiogenesis of MDA-MB-231 human breast adenocarcinoma cells by inhibiting focal adhesion kinase/Rho signaling pathway. Molecular Nutrition & Food Research, 55(2):318–27. doi: 10.1002/mnfr.201000148.


Tamir S, Eizenberg M, Somjen D, et al. (2000). Estrogenic and Anti-proliferative Properties of Glabridin from Licorice in Human Breast Cancer Cells. Cancer Res, 60:5704

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

Dietary Flavones

Cancer:
Prostate, colorectal., breast, pancreatic, bladder, ovarian, leukemia, liver, glioma, osteosarcoma, melanoma

Action: Anti-inflammatory, TAM resistance, cancer stem cells, down-regulate COX-2, apoptosis, cell-cycle arrest, anti-angiogenic, chemo-sensitzer, adramycin (ADM) resistance

Sulforaphane, Phenethyl isothiocyanate (PEITC), quercetin, epicatechin, catechin, Luteolin, apigenin

Anti-inflammatory

The anti-inflammatory activities of celery extracts, some rich in flavone aglycones and others rich in flavone glycosides, were tested on the inflammatory mediators tumor necrosis factor α (TNF-α) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in lipopolysaccharide-stimulated macrophages. Pure flavone aglycones and aglycone-rich extracts effectively reduced TNF-α production and inhibited the transcriptional activity of NF-κB, while glycoside-rich extracts showed no significant effects.

Celery diets with different glycoside or aglycone contents were formulated and absorption was evaluated in mice fed with 5% or 10% celery diets. Relative absorption in vivo was significantly higher in mice fed with aglycone-rich diets as determined by HPLC-MS/MS (where MS/MS is tandem mass spectrometry). These results demonstrate that deglycosylation increases absorption of dietary flavones in vivo and modulates inflammation by reducing TNF-α and NF-κB, suggesting the potential use of functional foods rich in flavones for the treatment and prevention of inflammatory diseases (Hostetler et al., 2012).

Colorectal Cancer

Association between the 6 main classes of flavonoids and the risk of colorectal cancer was examined using data from a national prospective case-control study in Scotland, including 1,456 incident cases and 1,456 population-based controls matched on age, sex, and residence area.

Dietary, including flavonoid, data were obtained from a validated, self-administered food frequency questionnaire. Risk of colorectal cancer was estimated using conditional logistic regression models in the whole sample and stratified by sex, smoking status, and cancer site and adjusted for established and putative risk factors.

The significant dose-dependent reductions in colorectal cancer risk that were associated with increased consumption of the flavonols quercetin, catechin, and epicatechin, remained robust after controlling for overall fruit and vegetable consumption or for other flavonoid intake. The risk reductions were greater among nonsmokers, but no interaction beyond a multiplicative effect was present.

This was the first of several a priori hypotheses to be tested in this large study and showed strong and linear inverse associations of flavonoids with colorectal cancer risk (Theodoratou et al., 2007).

Anti-angiogenic, Prostate Cancer

Luteolin is a common dietary flavonoid found in fruits and vegetables. The anti-angiogenic activity of luteolin was examined using in vitro, ex vivo, and in vivo models. Angiogenesis, the formation of new blood vessels from pre-existing vascular beds, is essential for tumor growth, invasion, and metastasis; hence, examination of this mechanism of tumor growth is essential to understanding new chemo-preventive targets. In vitro studies using rat aortic ring assay showed that luteolin at non-toxic concentrations significantly inhibited microvessel sprouting and proliferation, migration, invasion and tube formation of endothelial cells, which are key events in the process of angiogenesis. Luteolin also inhibited ex vivo angiogenesis as revealed by chicken egg chorioallantoic membrane assay (CAM) and matrigel plug assay.

Pro-inflammatory cytokines such as IL-1β, IL-6, IL-8, and TNF-α level were significantly reduced by the treatment of luteolin in PC-3 cells. Luteolin (10 mg/kg/d) significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model, indicating that luteolin inhibited tumorigenesis by targeting angiogenesis. Moreover, luteolin reduced cell viability and induced apoptosis in prostate cancer cells, which were correlated with the down-regulation of AKT, ERK, mTOR, P70S6K, MMP-2, and MMP-9 expressions.

Taken together, these findings demonstrate that luteolin inhibits human prostate tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis (Pratheeshkumar et al., 2012).

Pancreatic Cancer; Chemo-sensitizer

The potential of dietary flavonoids apigenin (Api) and luteolin (Lut) were assessed in their ability to enhance the anti-proliferative effects of chemotherapeutic drugs on BxPC-3 human pancreatic cancer cells; additionally, the molecular mechanism of the action was probed.

Simultaneous treatment with either flavonoid (0,13, 25 or 50µM) and chemotherapeutic drugs 5-fluorouracil (5-FU, 50µM) or gemcitabine (Gem, 10µM) for 60 hours resulted in less-than-additive effect (p<0.05). Pre-treatment for 24 hours with 13µM of either Api or Lut, followed by Gem for 36 hours was optimal to inhibit cell proliferation. Pre-treatment of cells with 11-19µM of either flavonoid for 24 hours resulted in 59-73% growth inhibition when followed by Gem (10µM, 36h). Lut (15µM, 24h) pre-treatment followed by Gem (10µM, 36h), significantly decreased protein expression of nuclear GSK-3β and NF-κB p65 and increased pro-apoptotic cytosolic cytochrome c. Pre-treatment of human pancreatic cancer cells BxPC-3 with low concentrations of Api or Lut hence effectively aid in the anti-proliferative activity of chemotherapeutic drugs (Johnson et al., 2013).

Breast Cancer; Chemo-sensitizer, Tamoxifen

The oncogenic molecules in human breast cancer cells are inhibited by luteolin treatment and it was found that the level of cyclin E2 (CCNE2) mRNA was higher in tumor cells than in normal paired tissue samples as assessed using real-time reverse-transcriptase polymerase chain reaction (RT-PCR) analysis (n=257).

Combined treatment with 4-OH-TAM and luteolin synergistically sensitized the TAM-R cells to 4-OH-TAM. These results suggest that luteolin can be used as a chemo-sensitizer to target the expression level of CCNE2 and that it could be a novel strategy to overcome TAM resistance in breast cancer patients (Tu et al., 2013).

Breast Cancer

Consumers of higher levels of Brassica vegetables, particularly those of the genus Brassica (broccoli, Brussels sprouts and cabbage), reduce their susceptibility to cancer at a variety of organ sites. Brassica vegetables contain high concentrations of glucosinolates that can be hydrolyzed by the plant enzyme, myrosinase, or intestinal microflora to isothiocyanates, potent inducers of cytoprotective enzymes and inhibitors of carcinogenesis. Oral administration of either the isothiocyanate, sulforaphane, or its glucosinolate precursor, glucoraphanin, inhibits mammary carcinogenesis in rats treated with 7,12-dimethylbenz[a]anthracene. To determine whether sulforaphane exerts a direct chemo-preventive action on animal and human mammary tissue, the pharmacokinetics and pharmacodynamics of a single 150 µmol oral dose of sulforaphane were evaluated in the rat mammary gland.

Sulforaphane metabolites were detected at concentrations known to alter gene expression in cell culture. Elevated cytoprotective NAD(P)H:quinone oxidoreductase (NQO1) and heme oxygenase-1 (HO-1) gene transcripts were measured using quantitative real-time polymerase chain reaction. An observed 3-fold increase in NQO1 enzymatic activity, as well as 4-fold elevated immunostaining of HO-1 in rat mammary epithelium, provide strong evidence of a pronounced pharmacodynamic action of sulforaphane. In a subsequent pilot study, eight healthy women undergoing reduction mammoplasty were given a single dose of a broccoli sprout preparation containing 200 µmol of sulforaphane. Following oral dosing, sulforaphane metabolites were readily measurable in human breast tissue enriched for epithelial cells. These findings provide a strong rationale for evaluating the protective effects of a broccoli sprout preparation in clinical trials of women at risk for breast cancer (Cornblatt et al., 2007).

In a proof of principle clinical study, the presence of disseminated tumor cells (DTCs) was demonstrated in human breast tissue after a single dose of a broccoli sprout preparation containing 200 µmol of sulforaphane. Together, these studies demonstrate that sulforaphane distributes to the breast epithelial cells in vivo and exerts a pharmacodynamic action in these target cells consistent with its mechanism of chemo-protective efficacy.

Such efficacy, coupled with earlier randomized clinical trials revealing the safety of repeated doses of broccoli sprout preparations , supports further evaluation of broccoli sprouts in the chemoprevention of breast and other cancers (Cornblatt et al., 2007).

CSCs

Recent research into the effects of sulforaphane on cancer stem cells (CSCs) has drawn a great deal of interest. CSCs are suggested to be responsible for initiating and maintaining cancer, and to contribute to recurrence and drug resistance. A number of studies have indicated that sulforaphane may target CSCs in different types of cancer through modulation of NF- κB, SHH, epithelial-mesenchymal transition and Wnt/β-catenin pathways. Combination therapy with sulforaphane and chemotherapy in preclinical settings has shown promising results (Li et al., 2013).

Anti-inflammatory

Sulforaphane has been found to down-regulate COX-2 expression in human bladder transitional cancer T24 cells at both transcriptional- and translational levels. Cyclooxygenase-2 (COX-2) overexpression has been associated with the grade, prognosis and recurrence of transitional cell carcinoma (TCC) of the bladder. Sulforaphane (5-20 microM) induced nuclear translocation of NF-kappaB and reduced its binding to the COX-2 promoter, a key mechanism for suppressing COX-2 expression by sulforaphane. Moreover, sulforaphane increased expression of p38 and phosphorylated-p38 protein. Taken together, these data suggest that p38 is essential in sulforaphane-mediated COX-2 suppression and provide new insights into the molecular mechanisms of sulforaphane in the chemoprevention of bladder cancer (Shan et al., 2009).

Bladder Cancer

An aqueous extract of broccoli sprouts potently inhibits the growth of human bladder carcinoma cells in culture and this inhibition is almost exclusively due to the isothiocyanates. Isothiocyanates are present in broccoli sprouts as their glucosinolate precursors and blocking their conversion to isothiocyanates abolishes the anti-proliferative activity of the extract.

Moreover, the potency of isothiocyanates in the extract in inhibiting cancer cell growth was almost identical to that of synthetic sulforaphane, as judged by their IC50 values (6.6 versus 6.8 micromol/L), suggesting that other isothiocyanates in the extract may be biologically similar to sulforaphane and that nonisothiocyanate substances in the extract may not interfere with the anti-proliferative activity of the isothiocyanates. These data show that broccoli sprout isothiocyanate extract is a highly promising substance for cancer prevention/treatment and that its anti-proliferative activity is exclusively derived from isothiocyanates (Tang et al., 2006).

Ovarian Cancer

Sulforaphane is an extract from the mustard family recognized for its anti-oxidation abilities, phase 2 enzyme induction, and anti-tumor activity. The cell-cycle arrest in G2/M by sulforaphane and the expression of cyclin B1, Cdc2, and the cyclin B1/CDC2 complex in PA-1 cells using Western blotting and co-IP Western blotting. The anti-cancer effects of dietary isothiocyanate sulforaphane on ovarian cancer were investigated using cancer cells line PA-1.

Sulforaphane -treated cells accumulated in metaphase by CDC2 down-regulation and dissociation of the cyclin B1/CDC2 complex.

These findings suggest that, in addition to the known effects on cancer prevention, sulforaphane may also provide anti-tumor activity in established ovarian cancer (Chang et al., 2013).

Leukemia Stem Cells

Isolated leukemia stem cells (LSCs) showed high expression of Oct4, CD133, β-catenin, and Sox2 and imatinib (IM) resistance. Differentially, CD34(+)/CD38(-) LSCs demonstrated higher BCR-ABL and β-catenin expression and IM resistance than CD34(+)/CD38(+) counterparts. IM and sulforaphane (SFN) combined treatment sensitized CD34(+)/CD38(-) LSCs and induced apoptosis, shown by increased caspase 3, PARP, and Bax while decreased Bcl-2 expression. Mechanistically, imatinib (IM) and sulforaphane (SFN) combined treatment resensitized LSCs by inducing intracellular reactive oxygen species (ROS). Importantly, β-catenin-silenced LSCs exhibited reduced glutathione S-transferase pi 1 (GSTP1) expression and intracellular GSH level, which led to increased sensitivity toward IM and sulforaphane.

It was hence demonstrated that IM and sulforaphane combined treatment effectively eliminated CD34(+)/CD38(-) LSCs. Since SFN has been shown to be well tolerated in both animals and human, this regimen could be considered for clinical trials (Lin et al., 2012).

DCIS Stem Cells

A miR-140/ALDH1/SOX9 axis has been found to be critical to basal cancer stem cell self-renewal and tumor formation in vivo, suggesting that the miR-140 pathway may be a promising target for preventive strategies in patients with basal-like Ductal Carcinoma in Situ (DCIS). The dietary compound sulforaphane has been found to decrease Transcription factor SOX-9 and Acetaldehyde dehydrogenases (ALDH1), and thereby reduced tumor growth in vivo (Li et al., 2013).

Glioma, Prostate Cancer, Colon Cancer, Breast Cancer, Liver Cancer

Phenethyl isothiocyanate (PEITC), a natural dietary isothiocyanate, inhibits angiogenesis. The effects of PEITC were examined under hypoxic conditions on the intracellular level of the hypoxia inducible factor (HIF-1α) and extracellular level of the vascular endothelial growth factor (VEGF) in a variety of human cancer cell lines. Gupta et al., (2013) observed that PEITC suppressed the HIF-1α accumulation during hypoxia in human glioma U87, human prostate cancer DU145, colon cancer HCT116, liver cancer HepG2, and breast cancer SkBr3 cells. PEITC treatment also significantly reduced the hypoxia-induced secretion of VEGF.

Suppression of HIF-1α accumulation during treatment with PEITC in hypoxia was related to PI3K and MAPK pathways.

Taken together, these results suggest that PEITC inhibits the HIF-1α expression through inhibiting the PI3K and MAPK signaling pathway and provide a new insight into a potential mechanism of the anti-cancer properties of PEITC.

Breast Cancer Metastasis

Breast tumor metastasis is a leading cause of cancer-related deaths worldwide. Breast tumor cells frequently metastasize to brain and initiate severe therapeutic complications. The chances of brain metastasis are further elevated in patients with HER2 overexpression. The MDA-MB-231-BR (BR-brain seeking) breast tumor cells stably transfected with luciferase were injected into the left ventricle of mouse heart and the migration of cells to brain was monitored using a non-invasive IVIS bio-luminescent imaging system.

Results demonstrate that the growth of metastatic brain tumors in PEITC treated mice was about 50% less than that of control. According to Kaplan Meir's curve, median survival of tumor-bearing mice treated with PEITC was prolonged by 20.5%. Furthermore, as compared to controls, we observed reduced HER2, EGFR and VEGF expression in the brain sections of PEITC treated mice. These results demonstrate the anti-metastatic effects of PEITC in vivo in a novel breast tumor metastasis model and provides the rationale for further clinical investigation (Gupta et al., 2013).

Osteosarcoma, Melanoma

Phenethyl isothiocyanate (PEITC) has been found to induce apoptosis in human osteosarcoma U-2 OS cells. The following end points were determined in regard to human malignant melanoma cancer A375.S2 cells: cell morphological changes, cell-cycle arrest, DNA damage and fragmentation assays and morphological assessment of nuclear change, reactive oxygen species (ROS) and Ca2+ generations, mitochondrial membrane potential disruption, and nitric oxide and 10-N-nonyl acridine orange productions, expression and activation of caspase-3 and -9, B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax), Bcl-2, poly (adenosine diphosphate-ribose) polymerase, and cytochrome c release, apoptosis-inducing factor and endonuclease G. PEITC

It was therefore concluded that PEITC-triggered apoptotic death in A375.S2 cells occurs through ROS-mediated mitochondria-dependent pathways (Huang et al., 2013).

Prostate Cancer

The glucosinolate-derived phenethyl isothiocyanate (PEITC) has recently been demonstrated to reduce the risk of prostate cancer (PCa) and inhibit PCa cell growth. It has been shown that p300/CBP-associated factor (PCAF), a co-regulator for the androgen receptor (AR), is upregulated in PCa cells through suppression of the mir-17 gene. Using AR-responsive LNCaP cells, the inhibitory effects of PEITC were observed on the dihydrotestosterone-stimulated AR transcriptional activity and cell growth of PCa cells.

Expression of PCAF was upregulated in PCa cells through suppression of miR-17. PEITC treatment significantly decreased PCAF expression and promoted transcription of miR-17 in LNCaP cells. Functional inhibition of miR-17 attenuated the suppression of PCAF in cells treated by PEITC. Results indicate that PEITC inhibits AR-regulated transcriptional activity and cell growth of PCa cells through miR-17-mediated suppression of PCAF, suggesting a new mechanism by which PEITC modulates PCa cell growth (Yu et al., 2013).

Bladder Cancer; Adramycin (ADM) Resistance

The role of PEITC on ADM resistance reversal of human bladder carcinoma T24/ADM cells has been examined, including an increased drug sensitivity to ADM, cell apoptosis rates, intracellular accumulation of Rhodamine-123 (Rh-123), an increased expression of DNA topoisomerase II (Topo-II), and a decreased expression of multi-drug resistance gene (MDR1), multi-drug resistance-associated protein (MRP1), bcl-2 and glutathione s transferase π (GST-π). The results indicated that PEITC might be used as a potential therapeutic strategy to ADM resistance through blocking Akt and activating MAPK pathway in human bladder carcinoma (Tang et al., 2013).

Breast Cancer; Chemo-enhancing

The synergistic effect between paclitaxel (taxol) and phenethyl isothiocyanate (PEITC) on the inhibition of breast cancer cells has been examined. Two drug-resistant breast cancer cell lines, MCF7 and MDA-MB-231, were treated with PEITC and taxol. Cell growth, cell-cycle, and apoptosis were examined.

The combination of PEITC and taxol significantly decreased the IC50 of PEITC and taxol over each agent alone. The combination also increased apoptosis by more than 2-fold over each single agent in both cell lines. A significant increase of cells in the G2/M phases was detected. Taken together, these results indicated that the combination of PEITC and taxol exhibits a synergistic effect on growth inhibition in breast cancer cells. This combination deserves further study in vivo (Liu et al., 2013).

References

Chang CC, Hung CM, Yang YR, Lee MJ, Hsu YC. (2013). Sulforaphane induced cell-cycle arrest in the G2/M phase via the blockade of cyclin B1/CDC2 in human ovarian cancer cells. J Ovarian Res, 6(1):41. doi: 10.1186/1757-2215-6-41


Cornblatt BS, Ye LX, Dinkova-Kostova AT, et al. (2007). Preclinical and clinical evaluation of sulforaphane for chemoprevention in the breast. Carcinogenesis, 28(7):1485-1490. doi: 10.1093/carcin/bgm049


Gupta B, Chiang L, Chae K, Lee DH. (2013). Phenethyl isothiocyanate inhibits hypoxia-induced accumulation of HIF-1 α and VEGF expression in human glioma cells. Food Chem, 141(3):1841-6. doi: 10.1016/j.foodchem.2013.05.006.


Gupta P, Adkins C, Lockman P, Srivastava SK. (2013). Metastasis of Breast Tumor Cells to Brain Is Suppressed by Phenethyl Isothiocyanate in a Novel In Vivo Metastasis Model. PLoS One, 8(6):e67278. doi:10.1371/journal.pone.0067278


Hostetler G, Riedl K, Cardenas H, et al. (2012). Flavone deglycosylation increases their anti-inflammatory activity and absorption. Molecular Nutrition & Food Research, 56(4):558-569. doi: 10.1002/mnfr.201100596


Huang SH, Hsu MH, Hsu SC, et al. (2013). Phenethyl isothiocyanate triggers apoptosis in human malignant melanoma A375.S2 cells through reactive oxygen species and the mitochondria-dependent pathways. Hum Exp Toxicol. doi: 10.1177/0960327113491508


Johnson JL, Gonzalez de Mejia E. (2013). Interactions between dietary flavonoids apigenin or luteolin and chemotherapeutic drugs to potentiate anti-proliferative effect on human pancreatic cancer cells, in vitro. Food Chem Toxicol, 60:83-91. doi: 10.1016/j.fct.2013.07.036.


Li Q, Yao Y, Eades G, Liu Z, Zhang Y, Zhou Q. (2013). Down-regulation of miR-140 promotes cancer stem cell formation in basal-like early stage breast cancer. Oncogene. doi: 10.1038/onc.2013.226.


Li Y, Zhang T. (2013). Targeting cancer stem cells with sulforaphane, a dietary component from broccoli and broccoli sprouts. Future Oncol, 9(8):1097-103. doi: 10.2217/fon.13.108.


Lin LC, Yeh CT, Kuo CC, et al. (2012). Sulforaphane potentiates the efficacy of imatinib against chronic leukemia cancer stem cells through enhanced abrogation of Wnt/ β-catenin function. J Agric Food Chem, 60(28):7031-9. doi: 10.1021/jf301981n.


Liu K, Cang S, Ma Y, Chiao JW. (2013). Synergistic effect of paclitaxel and epigenetic agent phenethyl isothiocyanate on growth inhibition, cell-cycle arrest and apoptosis in breast cancer cells. Cancer Cell Int, 13(1):10. doi: 10.1186/1475-2867-13-10.


Pratheeshkumar P, Son YO, Budhraja A, et al. (2012). Luteolin inhibits human prostate tumor growth by suppressing vascular endothelial growth factor receptor 2-mediated angiogenesis. PLoS One, 7(12):52279. doi: 10.1371/journal.pone.0052279.


Tang K, Lin Y, Li LM. (2013). The role of phenethyl isothiocyanate on bladder cancer ADM resistance reversal and its molecular mechanism. Anat Rec (Hoboken), 296(6):899-906. doi: 10.1002/ar.22677.


Tang L, Zhang Y, Jobson HE, et al. (2006). Potent activation of mitochondria-mediated apoptosis and arrest in S and M phases of cancer cells by a broccoli sprout extract. Mol Cancer Ther, 5(4):935-44. doi: 10.1158/1535-7163.MCT-05-0476


Theodoratou E, Kyle J, Cetnarskyj R, et al. (2007). Dietary flavonoids and the risk of colorectal cancer. Cancer Epidemiol Biomarkers Prev,16(4):684-93.


Tu SH, Ho CT, Liu MF, et al. (2013). Luteolin sensitizes drug-resistant human breast cancer cells to tamoxifen via the inhibition of cyclin E2 expression. Food Chem, 141(2):1553-61. doi: 10.1016/j.foodchem.2013.04.077.


Shan Y, Wu K, Wang W, et al. (2009). Sulforaphane down-regulates COX-2 expression by activating p38 and inhibiting NF-kappaB-DNA-binding activity in human bladder T24 cells. Int J Oncol, 34(4):1129-34.


Yu C, Gong AY, Chen D, et al. (2013). Phenethyl isothiocyanate inhibits androgen receptor-regulated transcriptional activity in prostate cancer cells through suppressing PCAF. Mol Nutr Food Res. doi: 10.1002/mnfr.201200810.

180, A549, angiogenesis, Anti-cancer, anti-inflammatory, Anti-metastatic, anti-tumor, apoptosis, Apoptotic, cell-cycle arrest, Chapter 7 Isolates and Cancer Research, Chemotherapy, cytotoxic, ERK, ERK1, HEK293, inflammation, inhibits angiogenesis, K562, K562/Adr, Lithospermum erythrorhizon, Lung cancer, MCF-7, MCF-7, MCF-7/Adr, MCF-7/Bcl-2, MCF-7/Bcl-x(L), MDR, Melanoma, metastasis, PI3K, ROS, Sarcoma, U87MG, Hs683, and M059K

Shikonin

Cancer: Sarcoma-180, lung, melanoma, leukemia

Action: Anti-inflammatory, inhibits angiogenesis, MDR

Shiunko is a Kampo herbal ointment often used for the treatment of burns in Japan. It is mainly isolated from the root of Lithospermum erythrorhizon (Siebold & Zuccarini), which had been used for treating tumors and inflammation in China since the 5th century. The naphthoquinone pigment shikonin is the most important pharmacologically active substance in the dried root of Lithospermum erythrorhizon. In traditional Chinese medicine root extracts of Lithospermum erythrorhizon have been used to treat macular eruption, measles, sore throat, carbuncles, and burns (Chen et al., 2002). The anti-tumor effect of shikonin was first evidenced by its activity against murine sarcoma-180 (Sankawa et al., 1977).

Melanoma

It has been reported that shikonin, the main chemical ingredient of L. erythrorhizon is a novel inhibitor of angiogenesis. Angiogenesis is critical for tumor growth and inflammation. It inhibited tumor necrosis factor-alpha-induced and B16 melanoma-induced angiogenesis in mice and normal developmental angiogenesis in the yolk-sac membranes of chick embryos. Shikonin also inhibited proliferation and migration of endothelial cells in culture and network formation by endothelial cells on Matrigel in vitro. The dose-responsive study suggests that the mechanism of this inhibitory effect on angiogenesis involves the prevention of network formation by endothelial cells via blocking integrin alpha v beta 3 expression (Hisa et al., 1998).

Anti-inflammatory

Shikonin also reported to exert anti-inflammatory and anti-cancer effects both in vitro and in vivo. It has been found that proteasome was a molecular target of shikonin in tumor cells, but whether shikonin targets macrophage proteasome needs to be investigated. Consistently, shikonin accumulated IκB-α, an inhibitor of NF-κB, and ubiquitinated proteins in rat primary macrophage cultures, demonstrating that the proteasome is a target of shikonin under inflammatory conditions.

Shikonin also induced macrophage cell apoptosis and cell death. These results demonstrate for the first time that proteasome inhibition by shikonin contributes to its anti-inflammatory effect. The novel finding about macrophage proteasome as a target of shikonin suggests that this medicinal compound has great potential to be developed into an anti-inflammatory agent (Lu et al., 2011).

Leukemia, MDR

Shikonin has a strong cytotoxic effect on a wide variety of cancer cell lines, especially different types of leukemia and several known MDR cell lines. Microarray-based gene expression analysis of U937 leukemia cells suggested that the cytotoxicity of shikonin is based on the disruption of normal mitochondrial function, overproduction of ROS, inhibition of cytoskeleton formation, and finally induction of cell-cycle arrest and apoptosis. These effects were validated using in vitro cell culture experiments exploiting the specific natural fluorescence of shikonin and thereby identifying the possible primary cellular mechanism of shikonin's cytotoxicity (Wiench et al., 2012).

Lung Cancer

To better understand the anti-metastatic role of shikonin in lung cancer, the effect of shikonin on lung cancer cell proliferation was investigated, as well as its adhesion to extracellular matrices (ECM), migration and invasion in non-small-cell lung cancer A549 cells. Taken together, findings provide new evidence that shikonin suppresses lung cancer invasion and metastasis by inhibiting integrin β1 expression and the ERK1/2 signaling pathway. Integrin β1 facilitates cancer cell adhesion, migration and metastasis by activating intracellular signaling pathways including the ERK and PI3K signaling pathways, and it is in this way that shikonin exerts its anti-cancer activity (Wang et al., 2013).

MDR

Numerous previous studies have proven that shikonin and its analogs not only are highly tumoricidal but also can bypass drug-transporter and apoptotic defect mediated drug resistance. Cancer drug resistance is a major obstacle for the success of chemotherapy. Since most clinical anti-cancer drugs could induce drug resistance, it is desired to develop candidate drugs that are highly efficacious but incompetent to induce drug resistance. Shikonin was investigated for its ability as an inducer of cancer drug resistance. Different cell lines (K562, MCF-7, and a MDR cell line K562/Adr), after repeatedly treated with shikonin for 18 months, were assayed for drug resistance and gene expression profiling. After an 18-month treatment, cells only developed a mere 2-fold resistance to shikonin and a marginal resistance to cisplatin and paclitaxel, without cross-resistance to shikonin analogs and other anti-cancer agents. These merits make shikonin and its analogs potential candidates for cancer therapy with the advantages of avoiding induction of drug resistance and bypassing existing drug resistance (Wu et al., 2013).

References

Chen X, Yang L, Oppenheim JJ, Howard OMZ. (2002). Cellular pharmacology studies of shikonin derivatives. Phytotherapy Research, 16(3):199–209.


Hisa T, Kimura Y, Takada K, Suzuki F, Takigawa M. (1998). Shikonin, an ingredient of Lithospermum erythrorhizon, inhibits angiogenesis in vivo and in vitro. Anti-cancer Res, 18(2A):783-90.


Lu L, Qin A, Huang H, et al. (2011). Shikonin extracted from medicinal Chinese herbs exerts anti-inflammatory effect via proteasome inhibition. Eur J Pharmacol. 658(2–3):242–247.


Sankawa U, Ebizuka Y, Miyazaki T, et al. (1977). Anti-tumor activity of shikonin and its derivatives. Chemical and Pharmaceutical Bulletin, 25(9):2392–2395.


Wang H, Wu C, Wan S, et al. (2013). Shikonin attenuates lung cancer cell adhesion to extracellular matrix and metastasis by inhibiting integrin β 1 expression and the ERK1/2 signaling pathway. Toxicology, 308:104-12. doi: 10.1016/j.tox.2013.03.015. Epub 2013 Apr 4.


Wiench B, Eichhorn T, Malte Paulsen M, Efferth T. (2012). Shikonin Directly Targets Mitochondria and Causes Mitochondrial Dysfunction in Cancer Cells. Evidence-Based Complementary and Alternative Medicine, 2012:726025. doi:10.1155/2012/726025


Wu H, Xie J, Pan Q, et al. (2013). Anti-cancer agent shikonin is an incompetent inducer of cancer drug resistance. PLoS One, 8(1):e52706. doi: 10.1371/journal.pone.0052706.

A2780, A549, Akt, angiogenesis, Anti-cancer, anti-metastasis, Anti-metastatic, anti-oxidant, anti-proliferative, anti-proliferative effect, anti-tubulin, anti-tumor, Apo2L, Apo2L/TRAIL, apoptosis, Apoptotic, Breast cancer, BxPC-3, Chapter 7 Isolates and Cancer Research, chemo-preventive, Chemo-sensitizer, Colon Cancer or Colorectal cancer, Down-regulates, down-regulates MMP-9, DR5, DU145, ER, G2/M, induces apoptosis, inhibits angiogenesis, inhibits proliferation, Lung cancer, MDA-MB-231, MDA-MB-453, metastasis, Ovarian cancer, Pancreatic cancer, Pro-apoptotic, Prostate cancer, Rectal cancer, SW480, DLD-1, LS174T, TAGLN, TRAIL, various fruits, vegetables

Apigenin

Cancer:
Breast, gastrointestinal., prostate, ovarian, pancreatic

Action: Anti-proliferative effect, induces apoptosis, chemo-sensitizer

Apigenin (4′,5,7-trihydroxyflavone, 5,7-dihydroxy-2-(4-hydroxyphenyl)-4H-1-benzopyran-4-one) is a flavonoid found in many fruits, vegetables, and herbs, the most abundant sources being the leafy herb parsley and dried flowers of chamomile. Present in dietary sources as a glycoside, it is cleaved in the gastrointestinal lumen to be absorbed and distributed as apigenin itself. For this reason, the epithelium of the gastrointestinal tract is exposed to higher concentrations of apigenin than tissues at other locations. This would also be true for epithelial cancers of the gastrointestinal tract. There is evidence that the actions of apigenin might hinder the ability of gastrointestinal cancers to progress and spread.

Induces Apoptosis, Anti-metastatic

Apigenin has been shown to inhibit cell growth, sensitize cancer cells to elimination by apoptosis, and hinder the development of blood vessels to serve the growing tumor. It also has actions that alter the relationship of the cancer cells with their microenvironment. Apigenin is able to reduce cancer cell glucose uptake, inhibit remodeling of the extracellular matrix, inhibit cell adhesion molecules that participate in cancer progression, and oppose chemokine signaling pathways that direct the course of metastasis into other locations. As such, apigenin may provide some additional benefit beyond existing drugs in slowing the emergence of metastatic disease (Lefort, 2013).

Chemo-sensitizer, Induces Apoptosis

Choi & Kim (2009) investigated the effects of combined treatment with 5-fluorouracil and apigenin on proliferation and apoptosis, as well as the underlying mechanism, in human breast cancer MDA-MB-453 cells. The MDA-MB-453 cells, which have been shown to overexpress ErbB2, were resistant to 5-fluorouracil; 5-fluorouracil exhibited a small dose-dependent anti-proliferative effect, with an IC50 of 90 microM. Interestingly, combined treatment with apigenin significantly decreased the resistance. Cellular proliferation was significantly inhibited in cells exposed to 5-fluorouracil at its IC50 and apigenin (5, 10, 50 and 100 microM), compared with proliferation in cells exposed to 5-fluorouracil alone.

This inhibition in turn led to apoptosis, as evidenced by an increased number of apoptotic cells and the activation of caspase-3. Moreover, compared with 5-fluorouracil alone, 5-fluorouracil in combination with apigenin at concentrations >10 microM exerted a pro-apoptotic effect via the inhibition of Akt expression.

Taken together, results suggest that 5-fluorouracil acts synergistically with apigenin inhibiting cell growth and inducing apoptosis via the down-regulation of ErbB2 expression and Akt signaling (Choi, 2009).

Breast Cancer, Prostate Cancer

Two flavonoids, genistein and apigenin, have been implicated as chemo-preventive agents against prostate and breast cancers; however, the mechanisms behind their respective cancer-protective effects may vary significantly. It was thought that the anti-proliferative action of these flavonoids on prostate (DU-145) and breast (MDA-MB-231) cancer cells expressing only estrogen receptor (ER) β is mediated by this ER subtype. It was found that both genistein and apigenin, although not 17β-estradiol, exhibited anti-proliferative effects and pro-apoptotic activities through caspase-3 activation in these two cell lines. In yeast transcription assays, both flavonoids displayed high specificity toward ERβ transactivation, particularly at lower concentrations.

However, in mammalian assay, apigenin was found to be more ERβ-selective than genistein, which has equal potency in inducing transactivation through ERα and ERβ. Small interfering RNA-mediated down-regulation of ERβ abrogated the anti-proliferative effect of apigenin in both cancer cells but did not reverse that of genistein. These results unveil that the anti-cancer action of apigenin is mediated, in part, by ERβ. The differential use of ERα and ERβ signaling for transaction between genistein and apigenin demonstrates the complexity of phytoestrogen action in the context of their anti-cancer properties (Mak, 2006).

Ovarian Cancer

Id1 (inhibitor of differentiation or DNA binding protein 1) contributes to tumorigenesis by stimulating cell proliferation, inhibiting cell differentiation and facilitating tumor neoangiogenesis. Elevated Id1 is found in ovarian cancers and its level correlates with the malignant potential of ovarian tumors. Therefore, Id1 is a potential target for ovarian cancer treatment. It has been demonstrated that apigenin inhibits proliferation and tumorigenesis of human ovarian cancer A2780 cells through Id1. Apigenin has been found to suppress the expression of Id1 through activating transcription factor 3 (ATF3). These results may elucidate a new mechanism underlying the inhibitory effects of apigenin on cancer cells (Li, 2009).

Pancreatic Cancer

Simultaneous treatment or pre-treatment (0, 6, 24 and 42 hours) of apigenin and chemotherapeutic drugs and various concentrations (0-50µM) were assessed using the MTS cell proliferation assay. Simultaneous treatment with apigenin (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 apigenin, followed by Gem for 36 hours was optimal to inhibit cell proliferation.

Pre-treatment of cells with 11-19µM of apigenin for 24 hours resulted in 59-73% growth inhibition when followed by Gem (10µM, 36h). Pre-treatment of human pancreatic cancer cells BxPC-3 with low concentrations of apigenin hence effectively aids in the anti-proliferative activity of chemotherapeutic drugs (Johnson, 2013).

Induces Apoptosis, Inhibits Angiogenesis and Metastasis.

Preclinical studies have also shown that Ocimum sanctum L. and some of the phytochemicals it contains (including apigenin) prevents chemical-induced skin, liver, oral., and lung cancers. These effects are thought to be mediated by increasing the anti-oxidant activity, altering gene expression, inducing apoptosis, and inhibiting angiogenesis and metastasis. The aqueous extract of Ocimum sanctum L. has been shown to protect mice against γ-radiation-induced sickness and mortality and to selectively protect the normal tissues against the tumoricidal effects of radiation. In particular, important phytochemicals like apigenin have also been shown to prevent radiation-induced DNA damage. This warrants its future research to establish its activity and utility in cancer prevention and treatment (Baliga, 2013).

Lung Cancer

Apigenin has been found to induce apoptosis and cell death in lung epithelium cancer (A549) cells with an IC50 value of 93.7 ± 3.7 µM for 48 hours treatment. Target identification investigations using A549 cells and in cell-free systems demonstrate that apigenin depolymerized microtubules and inhibited reassembly of cold depolymerized microtubules of A549 cells. Again apigenin inhibited polymerization of purified tubulin with an IC50 value of 79.8 ± 2.4 µM. Interestingly, apigenin also showed synergistic anti-cancer effects with another natural anti-tubulin agent, curcumin. Apigenin and curcumin synergistically induce cell death and apoptosis and also block cell-cycle progression at G2/M phase of A549 cells.

Understanding the mechanism of the synergistic effect of apigenin and curcumin could help to develop anti-cancer combination drugs from cheap and readily available nutraceuticals (Choudhury, 2013).

Induces Apoptosis

It has been shown that the dietary flavonoid apigenin binds and inhibits adenine nucleotide translocase-2 (ANT2), resulting in enhancement of Apo2L/TRAIL-induced apoptosis by up-regulation of DR5, making it a potential cancer therapeutic agent. Apigenin has been found to enhance Apo2L/TRAIL-induced apoptosis in cancer cells by inducing DR5 expression through binding ANT2. Similarly to apigenin, knockdown of ANT2 enhanced Apo2L/TRAIL-induced apoptosis by up-regulating DR5 expression at the post-transcriptional level.

Moreover, silencing of ANT2 attenuated the enhancement of Apo2L/TRAIL-induced apoptosis by apigenin. These results suggest that apigenin Up-regulates DR5 and enhances Apo2L/TRAIL-induced apoptosis by binding and inhibiting ANT2. ANT2 inhibitors like apigenin may hence contribute to Apo2L/TRAIL therapy (Oishi, 2013).

Colorectal Cancer

Apigenin has anti-proliferation, anti-invasion and anti-migration effects in three kinds of colorectal adenocarcinoma cell lines, namely SW480, DLD-1 and LS174T. Proteomic analysis with SW480 indicated that apigenin up-regulated the expression of transgelin (TAGLN) in mitochondria to exert its anti-tumor growth and anti-metastasis effects. Apigenin decreased the expression of MMP-9 in a dose-dependent manner. Transfection of three truncated forms of TAGLN and wild type has identified TAGLN as a repressor of MMP-9 expression.

This research provides direct evidence that apigenin inhibits tumor growth and metastasis both in vitro and in vivo. Apigenin up-regulates TAGLN and down-regulates MMP-9 expression through decreasing phosphorylation of Akt at Ser473 and in particular Thr308 to prevent cancer cell proliferation and migration (Chunhua, 2013).

References

Baliga MS, Jimmy R, Thilakchand KR, et al. (2013). Ocimum Sanctum L (Holy Basil or Tulsi) and Its Phytochemicals in the Prevention and Treatment of Cancer. Nutr Cancer, 65(1):26-35. doi: 10.1080/01635581.2013.785010.

 

 

Choi EJ, Kim GH. (2009). 5-Fluorouracil combined with apigenin enhances anti-cancer activity through induction of apoptosis in human breast cancer MDA-MB-453 cells. Oncol Rep, 22(6):1533-7.

 

Choudhury D, Ganguli A, Dastidar DG, et al. (2013). Apigenin shows synergistic anti-cancer activity with curcumin by binding at different sites of tubulin. Biochimie, 95(6):1297-309. doi: 10.1016/j.biochi.2013.02.010.

 

Chunhua L, Donglan L, Xiuqiong F, et al. (2013). Apigenin up-regulates transgelin and inhibits invasion and migration of colorectal cancer through decreased phosphorylation of AKT. J Nutr Biochem. doi: 10.1016/j.jnutbio.2013.03.006.

 

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, 20:83-91. doi: 10.1016/j.fct.2013.07.036.

 


Lefort ƒC, Blay J. (2013). Apigenin and its impact on gastrointestinal cancers. Mol Nutr Food Res, 57(1):126-44. doi: 10.1002/mnfr.201200424.

 

Li ZD, Hu XW, Wang YT & Fang J. (2009). Apigenin inhibits proliferation of ovarian cancer A2780 cells through Id1. FEBS Letters, 583(12):1999-2003 doi:10.1016/j.febslet.2009.05.013.

 

Mak P, Leung YK, Tang WY, Harwood C & Ho SM. (2006). Apigenin suppresses cancer cell growth through ERβ. Neoplasia, 8(11):896–904.

 

Oishi M, Iizumi Y, Taniguchi T, et al. (2013). Apigenin Sensitizes Prostate Cancer Cells to Apo2L/TRAIL by Targeting Adenine Nucleotide Translocase-2. PLoS One, 8(2):e55922. doi: 10.1371/journal.pone.0055922.

A549 and CH27, angiogenesis, Anti-angiogenic, Anti-cancer, anti-depressant, anti-inflammatory, Anti-metastatic, anti-tumor, Antibiotic, anxiolytic, apoptosis, Apoptotic, B-CLL, Breast cancer, Chapter 7 Isolates and Cancer Research, Chemo-sensitizer, Chemotherapy, Colon Cancer or Colorectal cancer, cytotoxic, Depression or Anxiety, HL-60, induces apoptosis, inflammation, inhibits angiogenesis, inhibits VEGF, Lung cancer, MCF-7/ADR, MDR, Multi-Drug Resistance, Multi-drug resistance, Multi-drug resistance reversal, Ovarian cancer, Pancreatic cancer, Prostate cancer, radio-sensitizing, RKO, Sarcoma, STAT, Uterine cancer, VEGF, VEGF

Honokiol (See also Injectables)

Cancer:
Lung, breast, prostate, leukemia, colorectal., esophageal., ovarian, myeloma, pancreatic, stomach, uterine

Action: Anti-angiogenic, chemo-sensitizer, multi-drug resistance reversal., anti-inflammatory, anxiolytic, anti-depressant, inhibits VEGF, anti-metastatic, synergistic effects with other cancer treatments

Honokiol is a phenolic compound purified from plants of the Magnolia genus, including Magnolia officinalis (Rehder & Wilson) and Magnolia grandiflora (L.), that exhibits anti-cancer effects in experimental models with various types of cancer cells, including esophageal., ovarian, breast, and lung cancer, as well as myeloma and leukemia. It is speculated that this compound causes cancer cell death in part through targeting mitochondria (Munroe et al., 2007; Chen et al., 2009; Fried & Arbiser, 2009).

Inhibits Angiogenesis, MDR, Anti-inflammatory, Inhibits VEGF

Honokiol is one of two dominant biphenolic compounds isolated from Magnolia spp. bark, and is the most widely researched active constituent of the bark. In vivo studies suggest that honokiol's greatest value is in its multiple anti-cancer actions. In vitro research suggests honokiol has potential to enhance current anti-cancer regimens by inhibiting angiogenesis, promoting apoptosis, providing direct cytotoxic activity, down-regulating cancer cell signaling pathways, regulating genetic expression, enhancing the effects of specific chemotherapeutic agents, radio-sensitizing cancer cells to radiation therapy, and inhibiting multi-drug resistance.

Honokiol also shows potential in preventive health by reducing inflammation and oxidative stress, providing neurological protection, and regulating glucose; in mental illness by its effects against anxiety and depression; and in helping regulate stress response signaling. Its anti-microbial effects demonstrate potential for partnering with anti-viral/antibiotic therapy, and treating secondary infections.

Honokiol may occupy a distinct therapeutic niche because of its unique characteristics: the ability to cross the blood brain barrier (BBB) and blood cerebrospinal fluid barrier (BCSFB), high systemic bioavailability, and its actions on a multiplicity of signaling pathways and genomic activity. There is a need for research on honokiol to progress to human studies and on into clinical use.

The preclinical research on honokiol's broad-ranging capabilities shows its potential as a therapeutic compound for numerous solid and hematological cancers, including its effectiveness in combating multi-drug resistance (MDR) and its synergy with other anti-cancer therapies. Research thus far shows no toxicity or serious adverse effects in animal models.

Honokiol has also been shown to inhibit spread of cancer cells through the lymph system by inhibiting one of the primary pathways involved in growth stimulation related to vascular endothelial growth factor (VEGF) (Wen et al., 2009).

Inhibits Angiogenesis, Gastric Cancer

A 2012 in vivo study in PLoS One showed that honokiol, by inhibiting angiogenic pathways such as STAT-3, dampened peritoneal dissemination of gastric cancer in mice (5 mg/kg delivered intraperitoneally) (Liu et al., 2012).    

Induces Apoptosis; Leukemia

Honokiol induces cell apoptosis in several cell lines, such as leukemia cell lines HL-60, colon cancer cell lines RKO, lung cancer cell lines A549 and CH27 (Hirano et al., 1994; Wang et al., 2004; Hibasami et al., 1998; Konoshima et al., 1991;Yang et al., 2002; Kong et al., 2005). It also has remarkable in vivo anti-tumor activities in tumor mouse models (Bai et al., 2003). Honokiol has demonstrated potent anti-angiogenic and anti-tumor properties against aggressive angiosarcoma by blocking of VEGF-induced VEGF receptor 2 autophosphorylation (Konoshima et al., 1991; Yang et al., 2002).

MDR

Honokiol has also been found to down-regulate the expression of P-glycoprotein at mRNA and protein levels in MCF-7/ADR, a human breast MDR cancer cell line. The down-regulation of P-glycoprotein is accompanied with a partial recovery of the intracellular drug accumulation (Xu et al., 2006).

Prostate Cancer

In addition, it has been shown that prostate cancer cells that failed to respond to hormone withdrawal responded to honokiol-induced apoptosis. It was found to significantly induce death in cells surrounding primary and metastatic prostate cancers, the prostate stromal fibroblasts, marrow stromal cells, and bone marrow-associated endothelial cells. Honokiol is hence a promising nontoxic agent that could be used as an adjuvant with low-dose docetaxel for the treatment of hormone-refractory prostate cancer and its distant bone metastases (Shigemura et al., 2007).

Anti-metastatic

Honokiol inhibited the activity of MMP-9, which may be responsible, in part, for the inhibition of tumor cell invasiveness (Nagase et al., 2001).

Breast Cancer

The development of more targeted and low toxic drugs from traditional Chinese medicines for breast cancer are needed due to most of the anti-breast cancer drugs often being limited because of drug resistance and serious adverse reactions. Results have shown that honokiol inhibited the rate of breast cancer MDA-MB-231 cell growth (Nagalingam et al., 2012).

Synergistic Effects with Other Cancer Treatments

One of the most promising benefits of honokiol is its ability to synergize with other cancer treatments. Clinical trials are desperately needed to validate the potential synergy that has been demonstrated in vitro and in vivo.

Chemotherapy

• A 2013 in vitro study published in the International Journal of Oncology showed that honokiol synergized chemotherapy drugs in Multi-drug-resistant breast cancer (Tian et al., 2013). A 2011 in vitro study published in PLoS One found that honokiol enhanced the apoptotic effects of the anti-cancer drug gemcitabine against pancreatic cancer (Arora et al., 2011).

• In vivo research published in Oncology Letters in 2011 found honokiol enhanced the action of cisplatin against colon cancer (Cheng et al., 2011).

• A 2010 in vitro study from the Journal of Biological Regulators and Homeostatic Agents showed that honokiol resensitized cancer cells to doxorubicin in Multi-drug-resistant uterine cancer (Angelini et al., 2010).

• A 2010 in vitro study published in Toxicology Mechanisms and Methods showed honokiol performed synergistically with the drug imatinib against human leukemia cells (Wang et al., 2010).

• 2008 in vivo research published in the International Journal of Gynecological Cancer showed honokiol to potentiate the activity of cisplatin in murine models of ovarian cancer (Liu et al., 2008).

• 2005 in vitro research published in Blood showed honokiol enhanced the cytotoxicity induced by fludarabine, cladribine, and chlorambucil, indicating it is a potent inducer of apoptosis in B-CLL cells (Battle et al., 2005).

Radiation treatment

• 2012 in vitro research published in Molecular Cancer Therapeutics showed that honokiol was able to sensitize cancer cells to radiation treatments (Ponnurangam et al., 2012).

• A 2011 in vitro study published in American Journal of Physiology Gastrointestinal and Liver Physiology showed honokiol sensitized treatment-resistant colon cancer cells to radiation therapy (He et al., 2011).

Inhibition of multi-drug resistance

Honokiol has been shown to interact with genes that are involved with mechanisms of drug efflux, thus reversing MDR in experimental models. The exact mechanisms of action in this regard are thought to be related to effects of blocking of NF-kB activity, but other mechanisms may also be involved (Xu et al., 2006).

References

Angelini A, Di Ilio C, Castellani ML, Conti P, Cuccurullo F. (2010). Modulation of Multi-drug resistance p-glycoprotein activity by flavonoids and honokiol in human doxorubicin-resistant sarcoma cells (MES-SA/DX-5): Implications for natural sedatives as chemosensitizing agents in cancer therapy. Journal of Biological Regulators & Homeostatic Agents, 24(2). 197-205.


Arora S, Bhardwaj A, Srivastava SK, et al. (2011). Honokiol arrests Cell-cycle, induces apoptosis, and potentiates the cytotoxic effect of gemcitabine in human pancreatic cancer cells. PLoS One, 6(6), e21573. doi: 10.1371/journal.pone.0021573.


Bai X, Cerimele F, Ushio-Fukai M, et al. (2003). Honokiol, a small molecular weight natural product, inhibits angiogenesis in vitro and tumor growth in vivo. J Biol Chem, 278: 35501–7.


Battle TE, Arbiser J, Frank DA. (2005). The natural product honokiol induces caspase-dependent apoptosis in B-cell chronic lymphocytic leukemia (B-CLL) cells. Blood, 106(2), 690-697.


Chen G, Izzo J, Demizu Y, et al. (2009). Different redox states in malignant and nonmalignant esophageal epithelial cells and differential cytotoxic responses to bile acid and honokiol. Antioxid. Redox Signal., 11(5):1083–1095


Cheng N, Xia T, Han Y, et al. (2001). Synergistic anti-tumor effects of liposomal honokiol combined with cisplatin in colon cancer models. Oncology Letters, 2(5), 957-962.


Eliaz I. (2013). Honokiol research review: A promising extract with multiple applications. Natural Medicine Journal., 5(7).


Fried LE, Arbiser JL. (2009). Honokiol, a multifunctional anti-angiogenic and anti-tumor agent. Antioxid. Redox Signal., 1(5):1139–1148. doi: 10.1089/ARS.2009.2440.


He Z, Subramaniam D, Ramalingam S, et al. (2011). Honokiol radiosensitizes colorectal cancer cells: enhanced activity in cells with mismatch repair defects. American Journal of Physiology: Gastrointest and Liver Physiology, 301(5):G929-937.


Hibasami H, Achiwa Y, Katsuzaki H, et al. (1998). Honokiol induces apoptosis in human lymphoid leukemia Molt 4B cells. Int J Mol Med, 2:671–3.


Hirano T, Gotoh M, Oka K. (1994). Natural flavonoids and lignans are potent cytostatic agents against human leukemic HL-60 cells. Life Sci, 55:1061–9.


Hou X, Yuan X, Zhang B, Wang S, Chen Q. (2013). Screening active anti-breast cancer compounds from Cortex Magnolia officinalis by 2D LC-MS. J Sep Sci, 36(4):706-12. doi: 10.1002/jssc.201200896.


Kong ZL, Tzeng SC, Liu YC. (2005). Cytotoxic neolignans: an SAR study. Bioorg Med Chem Lett, 15: 163–6.


Konoshima T, Kozuka M, Tokuda H, et al. (1991). Studies on inhibitors of skin tumor promotion. IX. Neolignans from Magnolia officinalis. J Nat Prod, 54: 816–22.


Liu Y, Chen L, He X, et al. (2010). Enhancement of therapeutic effectiveness by combining liposomal honokiol with cisplatin in ovarian carcinoma. International Journal of Gynecological Cancer, 18(4), 652-659.


Liu SH, Wang KB, Lan KH, et al. (2012). Calpain/SHP-1 interaction by honokiol dampening peritoneal dissemination of gastric cancer in nu/nu mice. PLoS One, 7(8):e43711.


Munroe ME, Arbiser JL, Bishop GA. (2007). Honokiol, a natural plant product, inhibits inflammatory signals and alleviates inflammatory arthritis. J. Immunol., 179(2):753–763


Nagalingam A, Arbiser JL, Bonner MY, Saxena NK, Sharma D. (2012). Honokiol activates AMP-activated protein kinase in breast cancer cells via an LKB1-dependent pathway and inhibits breast carcinogenesis. Breast Cancer Research, 14:R35 doi:10.1186/bcr3128


Nagase H, Ikeda K, Sakai Y. (2001). Inhibitory Effect of Magnolol and Honokiol from Magnolia obovata on Human Fibrosarcoma HT-1080 Invasiveness in vitro. Planta Med, 67(8): 705-708. DOI: 10.1055/s-2001-18345


Ponnurangam S, Mammen JM, Ramalingam S, et al. (2012). Honokiol in combination with radiation targets notch signaling to inhibit colon cancer stem cells. Molecular Cancer Therapeutics, 11(4), 963-972. doi: 10.1371/journal.pone.0043711.


Shigemura K, Arbiser JL, Sun SY, et al. (2007). Honokiol, a natural plant product, inhibits the bone metastatic growth of human prostate cancer cells. Cancer, 109(7), 1279-1289.


Tian W, Deng Y, Li L, et al. (2013). Honokiol synergizes chemotherapy drugs in Multi-drug-resistant breast cancer cells via enhanced apoptosis and additional programmed necrotic death. International Journal of Oncology, 42(2), 721-732. doi: 10.3892/ijo.2012.1739.


Wang Y, Yang Z, Zhao X. (2010). Honokiol induces parapoptosis and apoptosis and exhibits schedule-dependent synergy in combination with imatinib in human leukemia cells. Toxicology Mechanisms and Methods, 20(5), 234-241. doi: 10.3109/15376511003758831.


Wang T, Chen F, Chen Z, et al. (2004). Honokiol induces apoptosis through p53-independent pathway in human colorectal cell line RKO. World J Gastroenterol, 10: 2205–8.


Wen J, Fu AF, Chen LJ, et al. (2009). Liposomal honokiol inhibits VEGF-D-induced lymphangiogenesis and metastasis in xenograft tumor model. International Journal of Cancer, 124(11), 2709-2718. doi: 10.1002/ijc.24244.


Xu D, Lu Q, Hu X. (2006). Down-regulation of P-glycoprotein expression in MDR breast cancer cell MCF-7/ADR by honokiol. Cancer Letters, 243(2), 274-280.


Yang SE, Hsieh MT, Tsai TH, Hsu SL. (2002). Down-modulation of Bcl-XL, release of cytochrome c and sequential activation of caspases during honokiol-induced apoptosis in human squamous lung cancer CH27 cells. Biochemical Pharmacology, 63(9), 1641-1651.

Source

Eliaz I. (2013). Honokiol research review: A promising extract with multiple applications. Natural Medicine Journal., 5(7). Retrieved from http://www.naturalmedicinejournal.com/article_content.asp?edition=1.

Akt, angiogenesis, Anti-estrogenic, apoptosis, Apoptotic, Astragalus membranaceus, BAX, Breast cancer, Causes cell-cycle arrest, cell-cycle arrest, Cervical cancer, Chapter 7 Isolates and Cancer Research, Colon Cancer or Colorectal cancer, ER, ER-positive, ERK1, G0/G1, G1, growth-inhibitory, inhibits angiogenesis, MAPK, MCF-7, MCF-7 and T47D, MDR, PI3K, PI3K/Akt, Pro-apoptotic, Prostate cancer, ROS, VEGF, VEGF

Formononetin

Cancer: Prostate, colorectal., breast, cervical

Action: Cell-cycle arrest, MDR, growth-inhibitory

Estrogenic or Anti-estrogenic

Formononetin is one of the main active components of red clover plants, and considered as a phytoestrogen. Its pharmacological effects in vivo may be either estrogenic or anti-estrogenic, mainly depending upon the estrogen levels (Chen & Sun., 2012).

Cell-cycle Arrest, Prostate Cancer

Formononetin has been demonstrated to cause cell-cycle arrest at the G0/G1 phase by inactivating insulin-like growth factor 1(IGF1)/IGF1R-phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway in MCF-7 cells. The molecular mechanisms involved in the effect of formononetin on prostate cancer cells were hence investigated. These results suggest that higher concentrations of formononetin inhibit the proliferation of prostate cancer cells (LNCaP and PC-3), while the most striking effect was observed in LNCaP cells.

From these results, it was concluded that the induced apoptosis effect of formononetin on human prostate cancer cells was related to ERK1/2 MAPK-Bax pathway. Considering that red clover plants were widely used clinically, these results provided the foundation for future development of different concentrations of formononetin for treatment of prostate cancer (Ye et al., 2012).

Colon Cancer

Formononetin is a novel herbal isoflavonoid isolated from Astragalus membranaceus, a medicinal plant that possesses anti-tumorigenic properties. It has been demonstrated that formononetin initiates growth-inhibitory and pro-apoptotic activities in human colon cancer cells. The potential of formononetin in controlling angiogenesis and tumor cell invasiveness has further been examined in human colon cancer cells and tumor xenografts. The results showed that formononetin downregulated the expression of the key pro-angiogenic factors, including vascular endothelial growth factor (VEGF) and matrix metalloproteinases. The tumor size and the number of proliferating cells were reduced in the tumor tissues obtained from the formononetin-treated group.

The serum VEGF level was also reduced in the drug-treated animals when compared to the controls. These findings suggest that formononetin inhibits angiogenesis and tumor cell invasion, and thus support its use in the treatment of advanced and metastatic colon cancers (Auyeung et al., 2012).

Cervical Cancer

Formononetin may potentiate the cytotoxicity of epirubicin in HeLa cells through the ROS-mediated MRP inhibition and concurrent activation of the mitochondrial and death receptor pathways of apoptosis. Hence, the circumvention of pump and non-pump resistance using formononetin and epirubicin may pave the way for a powerful chemotherapeutic regimen for treating human cervical cancer (Lo et al., 2013).

Breast Cancer

Recent studies by Chen & Sun (2012) suggest that formononetin inactivated IGF1/IGF1R-PI3K/Akt pathways and decreased cyclin D1 mRNA and protein expression in human breast cancer cells in vitro and in vivo. In their present study, they further investigated the molecular mechanisms involved in the induced apoptosis effect of formononetin on breast cancer cells and formononetin inhibited the proliferation of ER-positive MCF-7 cells and T47D cells. The induced apoptosis effect of formononetin on human breast cancer cells was related to Ras-p38MAPK pathway.

Formononetin causes cell-cycle arrest at the G0/G1 phase by inactivating IGF1/IGF1R-PI3K/Akt pathways and decreasing cyclin D1 mRNA and protein expression, indicating the use of formononetin in the prevention of breast cancer carcinogenesis (Chen et al., 2011).

References

Auyeung KK, Law PC, Ko JK. (2012). Novel anti-angiogenic effects of formononetin in human colon cancer cells and tumor xenograft. Oncol Rep, 28(6):2188-94. doi: 10.3892/or.2012.2056.


Chen J, Zeng J, Xin M, Huang W, Chen X. (2011). Formononetin induces cell-cycle arrest of human breast cancer cells via IGF1/PI3K/Akt pathways in vitro and in vivo. Horm Metab Res, 43(10):681-6. doi: 10.1055/s-0031-1286306.


Chen J, Sun L. (2012). Formononetin-induced apoptosis by activation of Ras/p38 mitogen-activated protein kinase in estrogen receptor-positive human breast cancer cells. Horm Metab Res, 44(13):943-8. doi: 10.1055/s-0032-1321818.


Lo YL, Wang W. (2013). Formononetin potentiates epirubicin-induced apoptosis via ROS production in HeLa cells in vitro. Chem Biol Interact, 205(3):188-97. doi: 10.1016/j.cbi.2013.07.003.


Ye Y, Hou R, Chen J, et al. (2012). Formononetin-induced apoptosis of human prostate cancer cells through ERK1/2 mitogen-activated protein kinase inactivation. Horm Metab Res, 44(4):263-7. doi: 10.1055/s-0032-1301922.