Category Archives: Akt

Chrysin

Cancer:
Lung cancer, breast cancer, leukemia, gastric, colon

Action: Anti-inflammatory, induces apoptosis, inhibits HIF-1 α, immunomodulatory

Chrysin (5,7-dihydroxyflavone) is a natural and biologically active compound extracted from many plants (including Scutellaria baicalensis (Georgi), Passiflora caerulea (L.), Passiflora incarnate (L.))., honey, and propolis. It possesses potent anti-inflammatory, anti-oxidant properties, promotes cell death, and perturbs cell-cycle progression. Chrysin induced p38-MAPK activation, and using a specific p38-MAPK inhibitor, SB203580, attenuated chrysin-induced p21 (Waf1/Cip1) expression (Weng et al., 2005).

MDR; NSCLC

Chrysin is a major flavonoid in Scutellaria baicalensis, a widely used traditional Chinese and Japanese medicine. Novel links of pro-inflammatory signals, AKR1C1/1C2 expression and drug resistance in human non-small lung cancer have been demonstrated, and the protein kinase C pathway may play an important role in this process. It is thought that chrysin may act as a potential adjuvant therapy for drug-resistant non-small lung cancer, especially for those with AKR1C1/1C2 overexpression (Wang et al., 2007).

Gastric Cancer, Colon Cancer

Additionally, derivatives of chrysin have been shown to have strong activities against SGC-7901 human gastric cell line and HT-29 human colon cancer cell lines (Zheng et al., 2003).

Breast Cancer

While Chrysin is a potent breast cancer resistance protein inhibitor, it was found to have no significant effect on toptecan pharmacokinetics in rats (Zhang et al., 2005).

VEGF, HIF-1

Chrysin was found to inhibit hypoxia-inducible factor-1α (HIF-1α) expression through AKT signaling. Inhibition of HIF-1α by chrysin resulted in abrogation of vascular endothelial growth factor expression (Fu et al., 2007).

Leukemia

Chrysin has been shown to inhibit proliferation and induce apoptosis, and is more potent than other tested flavonoids in leukemia cells, where chrysin is likely to act via activation of caspases and inactivation of Akt signaling in the cells (Khoo et al., 2010).

Immune

The chemo-preventive action of chrysin has been found to specifically inhibit the enzymatic activity of IDO-1 but not mRNA expression in human neuronal stem cells (hNSC), confirmed by cell-based assay and qRT-PCR. These results suggest that attenuation of immune suppression via inhibition of IDO-1 enzyme activity may be one of the important mechanisms of polyphenols in chemoprevention or combinatorial cancer therapy (Chen et al., 2012).

References

Chen SS, Corteling R, Stevanato L, Sinden J. (2012). Polyphenols Inhibit Indoleamine 3,5-Dioxygenase-1 Enzymatic Activity — A Role of Immunomodulation in Chemoprevention. Discovery Medicine.


Fu B, Xue J, Li Z, et al. (2007). Chrysin inhibits expression of hypoxia-inducible factor-1 α through reducing hypoxia-inducible factor-1 α stability and inhibiting its protein synthesis. Mol Cancer Ther, 6:220. doi: 10.1158/1535-7163.MCT-06-0526


Khoo BY, Chua SL, Balaram P. (2010). Apoptotic Effects of Chrysin in Human Cancer Cell Lines. Int. J. Mol. Sci, 11(5), 2188-2199. doi:10.3390/ijms11052188


Wang HW, Lin CP, Chiu JH, et al. (2007). Reversal of inflammation-associated dihydrodiol dehydrogenases (AKR1C1 and AKR1C2) overexpression and drug resistance in nonsmall cell lung cancer cells by wogonin and chrysin. International Journal of Cancer, 120(9), 2019-2027.


Weng MS, Ho YS, Lin JK. (2005). Chrysin induces G1 phase cell-cycle arrest in C6 glioma cells through inducing p21Waf1/Cip1 expression: involvement of p38 mitogen-activated protein kinase. Biochem Pharmacol, 69(12):1815-27.


Zhang S, Wang X, Sagawa K, Morris ME. (2005). Flavonoids chrysin and benzoflavone, potent breast cancer resistance protein inhibitors, have no significant effect on topotecan pharmacokinetics in rats or mdr1a/1b (,äì/,äì) mice. Drug Metabolism and Disposition, 33(3), 341-348.


Zheng X, Meng WD, Xu YY, Cao JG, & Qing FL. (2003). Synthesis and anti-cancer effect of chrysin derivatives. Bioorganic & Medicinal Chemistry Letters, 13(5), 881-884.

Caffeic acid phenethyl ester (CAPE)

Cancer:
Breast, prostate, leukemia, cervical., oral., melanoma

Action: EMT, anti-mitogenic, anti-carcinogenic, anti-inflammatory, immunomodulatory

Anti-mitogenic, Anti-carcinogenic, Anti-inflammatory, Immunomodulatory Properties

Caffeic acid phenethyl ester (CAPE), an active component of propolis from honeybee hives, is known to have anti-mitogenic, anti-carcinogenic, anti-inflammatory, and immunomodulatory properties. A variety of in vitro pharmacology for CAPE has been reported. A study using CAPE showed a positive effect on reducing carcinogenic incidence. It is known to have anti-mitogenic, anti-carcinogenic, anti-inflammatory, and immunomodulatory properties in vitro (Orban et al., 2000) Another study also showed that CAPE suppresses acute immune and inflammatory responses and holds promise for therapeutic uses to reduce inflammation (Huang et al., 1996).

Caffeic acid phenethyl ester (CAPE) specifically inhibits NF-κB at µM concentrations and shows ability to stop 5-lipoxygenase-catalyzed oxygenation of linoleic acid and arachidonic acid. Previous studies have demonstrated that CAPE exhibits anti-oxidant, anti-inflammatory, anti-proliferative, cytostatic, anti-viral., anti-bacterial., anti-fungal., and, most importantly, anti-neoplastic properties (Akyol et al., 2013).

Multiple Immunomodulatory and Anti-inflammatory Activities

The results show that the activation of NF-kappa B by tumor necrosis factor (TNF) is completely blocked by CAPE in a dose- and time-dependent manner. Besides TNF, CAPE also inhibited NF-kappa B activation induced by other inflammatory agents including phorbol ester, ceramide, hydrogen peroxide, and okadaic acid. Since the reducing agents reversed the inhibitory effect of CAPE, it suggests the role of critical sulfhydryl groups in NF-kappa B activation. CAPE prevented the translocation of the p65 subunit of NF-kappa B to the nucleus and had no significant effect on TNF-induced I kappa B alpha degradation, but did delay I kappa B alpha resynthesis. When various synthetic structural analogues of CAPE were examined, it was found that a bicyclic, rotationally constrained, 5,6-dihydroxy form was superactive, whereas 6,7-dihydroxy variant was least active.

Thus, overall our results demonstrate that CAPE is a potent and a specific inhibitor of NF-kappa B activation and this may provide the molecular basis for its multiple immunomodulatory and anti-inflammatory activities (Natarajan et al., 1996).

Breast Cancer

Aqueous extracts from Thymus serpyllum (ExTs), Thymus vulgaris (ExTv), Majorana hortensis (ExMh), and Mentha piperita (ExMp), and the phenolic compounds caffeic acid (CA), rosmarinic acid (RA), lithospermic acid (LA), luteolin-7-O-glucuronide (Lgr), luteolin-7-O-rutinoside (Lr), eriodictiol-7-O-rutinoside (Er), and arbutin (Ab), were tested on two human breast cancer cell lines: Adriamycin-resistant MCF-7/Adr and wild-type MCF-7/wt.

ExMh showed the highest cytotoxicity, especially against MCF-7/Adr, whereas ExMp was the least toxic; particularly against MCF-7/wt cells. RA and LA exhibited the strongest cytotoxicity against both MCF-7 cell lines, over 2-fold greater than CA and Lgr, around 3-fold greater than Er, and around 4- to 7-fold in comparison with Lr and Ab. Except for Lr and Ab, all other phytochemicals were more toxic against MCF-7/wt, and all extracts exhibited higher toxicity against MCF-7/Adr. It might be concluded that the tested phenolics exhibited more beneficial properties when they were applied in the form of extracts comprising their mixtures (Berdowska et al., 2013).

Prostate Cancer

Evidence is growing for the beneficial role of selective estrogen receptor modulators (SERM) in prostate diseases. Caffeic acid phenethyl ester (CAPE) is a promising component of propolis that possesses SERM activity. CAPE-induced inhibition of AKT phosphorylation was more prominent (1.7-folds higher) in cells expressing ER-α such as PC-3 compared to LNCaP. In conclusion, CAPE enhances the anti-proliferative and cytotoxic effects of DOC and PTX in prostate cancer cells (Tolba et al., 2013).

EMT, Prostate Cancer

CAPE suppressed the expression of Twist 2 and growth of PANC-1 xenografts without significant toxicity. CAPE could inhibit the orthotopic growth and EMT of pancreatic cancer PANC-1 cells accompanied by down-regulation of vimentin and Twist 2 expression (Chen et al., 2013).

CAPE is a well-known NF-κB inhibitor. CAPE has been used in folk medicine as a potent anti-inflammatory agent. Recent studies indicate that CAPE treatment suppresses tumor growth and Akt signaling in human prostate cancer cells (Lin et al., 2013). Combined treatments of CAPE with chemotherapeutic drugs exhibit synergistic suppression effects. Pharmacokinetic studies suggest that intraperitoneal injection of CAPE at concentration of 10mg/kg is not toxic. CAPE treatment sensitizes cancer cells to chemotherapy and radiation treatments. In addition, CAPE treatment protects therapy-associated toxicities (Liu et al., 2013).

Cervical Cancer

CAPE preferentially induced S- and G2 /M-phase cell-cycle arrests and initiated apoptosis in human cervical cancer lines. The effect was found to be associated with increased expression of E2F-1, as there is no CAPE-mediated induction of E2F-1 in the pre-cancerous cervical Z172 cells. CAPE also up-regulated the E2F-1 target genes cyclin A, cyclin E and apoptotic protease activating of factor 1 (Apaf-1) but down-regulated cyclin B and induced myeloid leukemia cell differentiation protein (Mcl-1) (Hsu et al., 2013).

Oral Cancer

CAPE attenuated SCC-9 oral cancer cells migration and invasion at noncytotoxic concentrations (0  µM to 40 µM). CAPE exerted its inhibitory effects on MMP-2 expression and activity by upregulating tissue inhibitor of metalloproteinase-2 (TIMP-2) and potently decreased migration by reducing focal adhesion kinase (FAK) phosphorylation and the activation of its downstream signaling molecules p38/MAPK and JNK (Peng et al., 2012).

Melanoma

CAPE is suggested to suppress reactive-oxygen species (ROS)-induced DNA strand breakage in human melanoma A2058 cells when compared to other potential protective agents. CAPE can be applied not only as a chemo-preventive agent but also as an anti-metastatic therapeutic agent in lung cancer and because CAPE is a nuclear factor-κB (NF-κB) inhibitor and 5α reductase inhibitor, it has potential for the treatment of prostate cancer (Ozturk et al., 2012).

References

Akyol S, Ozturk G, Ginis Z, et al. (2013). In vivo and in vitro antõneoplastic actions of caffeic acid phenethyl ester (CAPE): therapeutic perspectives. Nutr Cancer, 65(4):515-26. doi: 10.1080/01635581.2013.776693.


Berdowska I, Ziel iński B, Fecka I, et al. (2013). Cytotoxic impact of phenolics from Lamiaceae species on human breast cancer cells. Food Chem, 15;141(2):1313-21. doi: 10.1016/j.foodchem.2013.03.090.


Chen MJ, Shih SC, Wang HY, et al. (2013). Caffeic Acid phenethyl ester inhibits epithelial-mesenchymal transition of human pancreatic cancer cells. Evid Based Complement Alternat Med, 2013:270906. doi: 10.1155/2013/270906.


Hsu TH, Chu CC, Hung MW, et al. (2013). Caffeic acid phenethyl ester induces E2F-1-mediated growth inhibition and cell-cycle arrest in human cervical cancer cells. FEBS J, 280(11):2581-93. doi: 10.1111/febs.12242.


Huang MT, Ma W, Yen P, et al. (1996). Inhibitory effects of caffeic acid phenethyl ester (CAPE) on 12-O-tetradecanoylphorbol-13-acetate-induced tumor promotion in mouse skin and the synthesis of DNA, RNA and protein in HeLa cells. Carcinogenesis, 17(4):761–5. doi:10.1093/carcin/17.4.761.


Lin HP, Lin CY, Liu CC, et al. (2013). Caffeic Acid phenethyl ester as a potential treatment for advanced prostate cancer targeting akt signaling. Int J Mol Sci, 14(3):5264-83. doi: 10.3390/ijms14035264.


Liu CC, Hsu JM, Kuo LK, et al. (2013). Caffeic acid phenethyl ester as an adjuvant therapy for advanced prostate cancer. Med Hypotheses, 80(5):617-9. doi: 10.1016/j.mehy.2013.02.003.


Natarajan K, Singh S, Burke TR Jr, Grunberger D, Aggarwal BB. (1996). Caffeic acid phenethyl ester is a potent and specific inhibitor of activation of nuclear transcription factor NF-kappa B. Proc Natl Acad Sci USA, 93(17):9090-5.


Orban Z, Mitsiades N, Burke TR, Tsokos M, Chrousos GP. (2000). Caffeic acid phenethyl ester induces leukocyte apoptosis, modulates nuclear factor-kappa B and suppresses acute inflammation. Neuroimmunomodulation, 7(2): 99–105. doi:10.1159/000026427.


Ozturk G, Ginis Z, Akyol S, et al. (2012). The anti-cancer mechanism of caffeic acid phenethyl ester (CAPE): review of melanomas, lung and prostate cancers. Eur Rev Med Pharmacol Sci, 16(15):2064-8.


Peng CY, Yang HW, Chu YH, et al. (2012). Caffeic Acid phenethyl ester inhibits oral cancer cell metastasis by regulating matrix metalloproteinase-2 and the mitogen-activated protein kinase pathway. Evid Based Complement Alternat Med, 2012:732578. doi: 10.1155/2012/732578.


Tolba MF, Esmat A, Al-Abd AM, et al. (2013). Caffeic acid phenethyl ester synergistically enhances docetaxel and paclitaxel cytotoxicity in prostate cancer cells. IUBMB Life, 65(8):716-29. doi: 10.1002/iub.1188.

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.

Artemisinin

Cancer: Breast, leukemia, gastric

Action: Anti-cancer

Artemisinin is isolated from Artemisia annua (L.).

Anti-cancer

Artemisinin and related compounds (artemisinins) is a frontline treatment for malaria. According to experimental evidence from more than 400 literature studies, 558 key proteins were derived and the artemisinins-rewired protein interaction network was constructed. Topological properties were analyzed to show that the protein network was a scale-free biological system. Five key pathways including PI3K-Akt, T cell receptor, Toll-like receptor, TGF-beta and insulin signaling pathways were involved in artemisinins-mediated anti-cancer effects (Huang et al., 2013).

Breast Cancer

Artemisinin has previously been shown to have selective toxicity towards cancer cells in vitro. The potential of artemisinin to prevent breast cancer development has been investigated in rats treated with a single oral dose (50 mg/kg) of 7,12-dimethylbenz[a]anthracene (DMBA), known to induce multiple breast tumors. Starting from the day immediately after DMBA treatment, one group of rats was provided with a powdered rat-chow containing 0.02% artemisinin, whereas a control group was provided with plain powdered food. For 40 weeks, both groups of rats were monitored for breast tumors.

Oral artemisinin significantly delayed (P<.002) and in some animals prevented (57% of artemisinin-fed versus 96% of the controls developed tumors, P<.01) breast cancer development in the monitoring period. In addition, breast tumors in artemisinin-fed rats were significantly fewer (P<.002) and smaller in size (P<.05) when compared with controls. Since artemisinin is a relatively safe compound that causes no known side-effects even at high oral doses, the present data indicate that artemisinin may be a potent chemoprevention agent (Lai, 2006).

Leukemia

Artemisinin is also a well-known anti-leukemic agent. The effect of artemisinin on cellular differentiation in the human promyelocytic leukemia HL-60 cell culture system has been investigated. Artemisinin markedly increased the degree of HL-60 leukemia cell differentiation when simultaneously combined with low doses of 1α,25-dihydoxyvitamin D3 [1,25-(OH)2D3] or all-trans retinoic acid (all-trans RA).

Extracellular-regulated kinase (ERK) inhibitors markedly inhibited HL-60 cell differentiation induced by artemisinin in combination with 1,25-(OH)2D3 or all-trans RA, whereas phosphatidylinositol 3-kinase (PI3-K) inhibitors did not. Particularly, protein kinase C (PKC) inhibitors inhibited HL-60 cell differentiation induced by artemisinin in combination with 1,25-(OH)2D3 but not with all-trans RA. Artemisinin enhanced PKC activity and protein level of PKCβI isoform in only 1,25-(OH)2D3-treated HL-60 cells.

Taken together, these results indicate that artemisinin strongly enhances the action of low doses of 1α,25-dihydoxyvitamin D3 [1,25-(OH)2D3] and all-trans retinoic acid in leukemia cell differentiation (Kim, 2003).

Gastric Cancer

Zhang et al. (2013) found that artemisinin inhibited growth and modulated expression of cell-cycle regulators in gastric cancer cells (AGS and MKN74 cells). Treatment with artemisinin was also associated with induction of p27kip1 and p21kip1, two negative cell-cycle regulators. Furthermore, we revealed that artemisinin treatment led to an increased expression of p53.

The side-effects from the artemisinin class of medications are similar to the symptoms of malaria: nausea, vomiting, anorexia, and dizziness. Mild blood abnormalities have also been noted. A rare but serious adverse effect is allergic reaction (Leonardi et al., 2001).

References

Huang C, Ba Q, Yue Q, et al. (2013). Artemisinin rewires the protein interaction network in cancer cells: network analysis, pathway identification, and target prediction. Mol Biosyst. Kim SH, Kim HJ, Kim TS. (2003). Differential involvement of protein kinase C in human promyelocytic leukemia cell differentiation enhanced by artemisinin. European Journal of Pharmacology, 482(1–3):67–76. doi:10.1016/j.ejphar.2003.09.057.


Lai H, Singh NP. (2006). Oral artemisinin prevents and delays the development of 7, 12-dimethylbenz [a] anthracene (DMBA)-induced breast cancer in the rat. Cancer Letters, 231(1):43–48. doi: 10.1016/j.canlet.2005.01.019.


Leonardi E, Gilvary G, White NJ, Nosten F. (2001). Severe allergic reactions to oral artesunate: a report of two cases'. Trans. R. Soc. Trop. Med. Hyg, 95(2):182–3. doi:10.1016/S0035-9203(01)90157-9.


Sun H, Meng X, Han J, et al. (2013) Anti-cancer activity of DHA on gastric cancer-an in vitro and in vivo study. Tumor Biol.


Zhang HT, Wang YL, Zhang J, Zhang QX. (2013). Artemisinin inhibits gastric cancer cell proliferation through up-regulation of p53. Tumor Biol.

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.

Angelicin

Cancer: Leukemia, colon, ER+ Ovarian

Action: Apoptotic, anti-cancer

Angelicin is a furanocoumarin. It can be found in Bituminaria bituminosa and is structurally related to psoralens, a well-known chemical class of photosensitizers used for its anti-proliferative activity in treatment of different skin diseases.

Induces Apoptosis

The cellular cytotoxicity of angelicin was examined by cell viability assay, DNA fragmentation by DNA ladder assay, and activation of caspases and Bcl-2 family proteins by Western blot analyzes. The results suggest that angelicin increased cellular cytotoxicity in a dose- and time-dependent manner with IC(50) of 49.56 µM at 48 hours of incubation.

In addition, angelicin dose-dependently downregulated the expression of anti-apoptotic proteins including Bcl-2, Bcl-xL, and Mcl-1 suggesting the involvement of the intrinsic mitochondria-mediated apoptotic pathway which did not participate in Fas/FasL-induced caspase-8-mediated extrinsic, MAP kinases, and PI3K/AKT/GSK-3β pathway.

Taken together, these data indicate that angelicin is an effective apoptosis-inducing natural compound of human SH-SY5Y neuroblastoma cells which suggests that this compound may have a role in future therapies for human neuroblastoma cancer (Rahman et al., 2012).

Anti-cancer

Three crude drugs Saussureae Radix, Psoraleae Semen and Aurantti Fructus Immaturus significantly inhibited the proliferation of temperature-sensitive rat lymphatic endothelial (TR-LE) cells in vitro. Angelicin isolated from Aurantti Fructus Immaturus showed selective inhibition of the proliferation of TR-LE cells (Jeong et al., 2013). Angelicin, isolated from Bituminaria morisiana was subjected to cytotoxicity screening against a panel of human cancer cells (Leonti et al., 2010).

References

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


Leonti M, Casu L, Gertsch J, et al. (2010). A pterocarpan from the seeds of Bituminaria morisiana. J Nat Med. 64(3):354-7. doi: 10.1007/s11418-010-0408-7.


Rahman MA, Kim NH, Yang H, Huh SO. (2012). Angelicin induces apoptosis through intrinsic caspase-dependent pathway in human SH-SY5Y neuroblastoma cells. Mol Cell Biochem, 369(1-2):95-104. doi: 10.1007/s11010-012-1372-1.

Alisol B Acetate

Cancer:
Liver, melanoma, ovarian, sarcoma, gastric cancer

Action: Cytostatic, cytotoxic

Four prostane-type triterpenes were isolated from a methanol extract of Alismatis Rhizoma by bioassay-guided isolation using in vitro cytotoxic assay. The compounds were identified as alisol B 23-acetate (1), alisol C 23-acetate (2), alisol B (3), alisol A 24-acetate (4) by spectroscopic methods. Amongst the compounds, alisol B (3) showed significant cytotoxicity against SK-OV3, B16-F10, and HT1080 cancer cell lines with ED50 values of 7.5, 7.5, 4.9 microg/ml, respectively (Lee et al., 2001).

Hepatocellular Carcinoma

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

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

Gastric Cancer

The cytotoxic effect of alisol B acetate on SGC7901 cells was measured by MTT assay and phase-contrast and electron microscopy. Cell-cycle and mitochondrial transmembrane potential (Deltapsim) were determined by flow cytometry and Western blotting was used to detect the expression of apoptosis-regulated gene Bcl-2, Bax, Apaf-1, caspase-3, caspase-9, Akt, P-Akt and phosphatidylinositol 3-kinases (PI3K).

Alisol B acetate inhibited the proliferation of SGC7901 cell line in a time- and dose-dependent manner. Alisol B acetate exhibits an anti-proliferative effect in SGC7901 cells by inducing apoptosis. Apoptosis of SGC7901 cells involves mitochondria-caspase and PI3K/Akt dependent pathways (Xu, Zhao & Li, 2009).

References

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

 

 

Lee S, Kho Y, Min B, et al. (2001). Cytotoxic triterpenoides from Alismatis rhizome. Archives of Pharmacal Research. 24(6), 524-526.

 

Xu YH, Zhao LJ, & Li Y. (2009). Alisol B acetate induces apoptosis of SGC7901 cells via mitochondrial and phosphatidylinositol 3-kinases/Akt signaling pathways.

 

World Journal of Gastroenterology, 15(23), 2870-2877.

Thymoquinone

Cancer: Osteosarcoma, pancreatic, colorectal., lung, liver, melanoma, breast

Action: Anti-inflammatory

For centuries, the black seed (Nigella sativa (L.)) herb and oil have been used in Asia, Middle East and Africa to promote health and fight disease. Thymoquinone (TQ) is the major phytochemical constituent of Nigella sativa (L.) oil extract. Phytochemical compounds are emerging as a new generation of anti-cancer agents with limited toxicity in cancer patients.

Osteosarcoma

The anti-proliferative and pro-apoptotic effects of TQ were evaluated in two human osteosarcoma cell lines with different p53 mutation status. TQ decreased cell survival dose-dependently and, more significantly, in p53-null MG63 cells (IC(50) = 17 muM) than in p53-mutant MNNG/HOS cells (IC(50) = 38 muM). Cell viability was reduced more selectively in MG63 tumor cells than in normal human osteoblasts.

It was therefore suggested that the resistance of MNNG/HOS cells to drug-induced apoptosis is caused by the up-regulation of p21(WAF1) by the mutant p53 (transcriptional activity was shown by p53 siRNA treatment) which induces cell-cycle arrest and allows repair of DNA damage.

Collectively, these findings show that TQ induces p53-independent apoptosis in human osteosarcoma cells. As the loss of p53 function is frequently observed in osteosarcoma patients, these data suggest the potential clinical usefulness of TQ for the treatment of these malignancies (Roepke et al., 2007).

Pancreatic Ductal Adenocarcinoma

Inflammation has been identified as a significant factor in the development of solid tumor malignancies. It has recently been shown that thymoquinone (Tq) induces apoptosis and inhibited proliferation in PDA cells. The effect of Tq on the expression of different pro-inflammatory cytokines and chemokines was analyzed by real-time polymerase chain reaction (PCR). Tq dose- and time-dependently significantly reduced PDA cell synthesis of MCP-1, TNF-alpha, interleukin (IL)-1beta and Cox-2. Tq also inhibited the constitutive and TNF-alpha-mediated activation of NF-kappaB in PDA cells and reduced the transport of NF-kappaB from the cytosol to the nucleus. Our data demonstrate previously undescribed anti-inflammatory activities of Tq in PDA cells, which are paralleled by inhibition of NF-kappaB. Tq as a novel inhibitor of pro-inflammatory pathways provides a promising strategy that combines anti-inflammatory and pro-apoptotic modes of action (Chehl et al., 2009).

Lung cancer, Hepatoma, Melanoma, Colon Cancer, Breast Cancer

The potential impact of thymoquinone (TQ) was investigated on the survival., invasion of cancer cells in vitro, and tumor growth in vivo. Exposure of cells derived from lung (LNM35), liver (HepG2), colon (HT29), melanoma (MDA-MB-435), and breast (MDA-MB-231 and MCF-7) tumors to increasing TQ concentrations resulted in a significant inhibition of viability through the inhibition of Akt phosphorylation leading to DNA damage and activation of the mitochondrial-signaling pro-apoptotic pathway. Administration of TQ (10 mg/kg/i.p.) for 18 days inhibited the LNM35 tumor growth by 39% (P < 0.05). Tumor growth inhibition was associated with significant increase in the activated caspase-3. In this context, it has been demonstrated that TQ treatment resulted in a significant inhibition of HDAC2 proteins. In view of the available experimental findings, it is contended that thymoquinone and/or its analogues may have clinical potential as an anti-cancer agent alone or in combination with chemotherapeutic drugs such as cisplatin (Attoub et al., 2012).

Colon Cancer

It was reported that TQ inhibits the growth of colon cancer cells which was correlated with G1 phase arrest of the cell-cycle. Furthermore, TUNEL staining and flow cytometry analysis indicate that TQ triggers apoptosis in a dose- and time-dependent manner. These results indicate that TQ is anti-neoplastic and pro-apoptotic against colon cancer cell line HCT116. The apoptotic effects of TQ are modulated by Bcl-2 protein and are linked to and dependent on p53. Our data support the potential for using the agent TQ for the treatment of colon cancer (Gali-Muhtasib et al., 2004).

References

Attoub S, Sperandio O, Raza H, et al. (2012). Thymoquinone as an anti-cancer agent: evidence from inhibition of cancer cells viability and invasion in vitro and tumor growth in vivo. Fundam Clin Pharmacol, 27(5):557-569. doi: 10.1111/j.1472-8206.2012.01056.x


Chehl N, Chipitsyna G, Gong Q, Yeo CJ, Arafat HA. (2009). Anti-inflammatory effects of the Nigella sativa seed extract, thymoquinone, in pancreatic cancer cells. HPB (Oxford), 11(5):373-81. doi: 10.1111/j.1477-2574.2009.00059.x.


Gali-Muhtasib H, Diab-Assaf M, Boltze C, et al. (2004). Thymoquinone extracted from black seed triggers apoptotic cell death in human colorectal cancer cells via a p53-dependent mechanism. Int J Oncol, 25(4):857-66


Roepke M, Diestel A, Bajbouj K, et al. (2007). Lack of p53 augments thymoquinone-induced apoptosis and caspase activation in human osteosarcoma cells. Cancer Biol Ther, 6(2):160-9.

Thymoquinone

Cancer: Osteosarcoma, pancreatic, colorectal., lung, liver, melanoma, breast

Action: Anti-inflammatory

For centuries, the black seed (Nigella sativa (L.)) herb and oil have been used in Asia, Middle East and Africa to promote health and fight disease. Thymoquinone (TQ) is the major phytochemical constituent of Nigella sativa (L.) oil extract. Phytochemical compounds are emerging as a new generation of anti-cancer agents with limited toxicity in cancer patients.

Osteosarcoma

The anti-proliferative and pro-apoptotic effects of TQ were evaluated in two human osteosarcoma cell lines with different p53 mutation status. TQ decreased cell survival dose-dependently and, more significantly, in p53-null MG63 cells (IC(50) = 17 muM) than in p53-mutant MNNG/HOS cells (IC(50) = 38 muM). Cell viability was reduced more selectively in MG63 tumor cells than in normal human osteoblasts.

It was therefore suggested that the resistance of MNNG/HOS cells to drug-induced apoptosis is caused by the up-regulation of p21(WAF1) by the mutant p53 (transcriptional activity was shown by p53 siRNA treatment) which induces cell-cycle arrest and allows repair of DNA damage.

Collectively, these findings show that TQ induces p53-independent apoptosis in human osteosarcoma cells. As the loss of p53 function is frequently observed in osteosarcoma patients, these data suggest the potential clinical usefulness of TQ for the treatment of these malignancies (Roepke et al., 2007).

Pancreatic Ductal Adenocarcinoma

Inflammation has been identified as a significant factor in the development of solid tumor malignancies. It has recently been shown that thymoquinone (Tq) induces apoptosis and inhibited proliferation in PDA cells. The effect of Tq on the expression of different pro-inflammatory cytokines and chemokines was analyzed by real-time polymerase chain reaction (PCR). Tq dose- and time-dependently significantly reduced PDA cell synthesis of MCP-1, TNF-alpha, interleukin (IL)-1beta and Cox-2. Tq also inhibited the constitutive and TNF-alpha-mediated activation of NF-kappaB in PDA cells and reduced the transport of NF-kappaB from the cytosol to the nucleus. Our data demonstrate previously undescribed anti-inflammatory activities of Tq in PDA cells, which are paralleled by inhibition of NF-kappaB. Tq as a novel inhibitor of pro-inflammatory pathways provides a promising strategy that combines anti-inflammatory and pro-apoptotic modes of action (Chehl et al., 2009).

Lung cancer, Hepatoma, Melanoma, Colon Cancer, Breast Cancer

The potential impact of thymoquinone (TQ) was investigated on the survival., invasion of cancer cells in vitro, and tumor growth in vivo. Exposure of cells derived from lung (LNM35), liver (HepG2), colon (HT29), melanoma (MDA-MB-435), and breast (MDA-MB-231 and MCF-7) tumors to increasing TQ concentrations resulted in a significant inhibition of viability through the inhibition of Akt phosphorylation leading to DNA damage and activation of the mitochondrial-signaling pro-apoptotic pathway. Administration of TQ (10 mg/kg/i.p.) for 18 days inhibited the LNM35 tumor growth by 39% (P < 0.05). Tumor growth inhibition was associated with significant increase in the activated caspase-3. In this context, it has been demonstrated that TQ treatment resulted in a significant inhibition of HDAC2 proteins. In view of the available experimental findings, it is contended that thymoquinone and/or its analogues may have clinical potential as an anti-cancer agent alone or in combination with chemotherapeutic drugs such as cisplatin (Attoub et al., 2012).

Colon Cancer

It was reported that TQ inhibits the growth of colon cancer cells which was correlated with G1 phase arrest of the cell-cycle. Furthermore, TUNEL staining and flow cytometry analysis indicate that TQ triggers apoptosis in a dose- and time-dependent manner. These results indicate that TQ is anti-neoplastic and pro-apoptotic against colon cancer cell line HCT116. The apoptotic effects of TQ are modulated by Bcl-2 protein and are linked to and dependent on p53. Our data support the potential for using the agent TQ for the treatment of colon cancer (Gali-Muhtasib et al., 2004).

References

Attoub S, Sperandio O, Raza H, et al. (2012). Thymoquinone as an anti-cancer agent: evidence from inhibition of cancer cells viability and invasion in vitro and tumor growth in vivo. Fundam Clin Pharmacol, 27(5):557-569. doi: 10.1111/j.1472-8206.2012.01056.x


Chehl N, Chipitsyna G, Gong Q, Yeo CJ, Arafat HA. (2009). Anti-inflammatory effects of the Nigella sativa seed extract, thymoquinone, in pancreatic cancer cells. HPB (Oxford), 11(5):373-81. doi: 10.1111/j.1477-2574.2009.00059.x.


Gali-Muhtasib H, Diab-Assaf M, Boltze C, et al. (2004). Thymoquinone extracted from black seed triggers apoptotic cell death in human colorectal cancer cells via a p53-dependent mechanism. Int J Oncol, 25(4):857-66


Roepke M, Diestel A, Bajbouj K, et al. (2007). Lack of p53 augments thymoquinone-induced apoptosis and caspase activation in human osteosarcoma cells. Cancer Biol Ther, 6(2):160-9.

Luteolin

Cancer: Colorectal., pancreatic, ovarian, breast

Action: Anti-inflammatory, radio-protective, TAM chemo-sensitizer

Luteolin is a flavonoid found in many plants and foods, including Terminalia chebula (Retz.), Prunella vulgaris (L.) and Perilla frutescens [(L.) Britton].

Luteolin is contained in Ocimum sanctum L. or Ocimum tenuiflorum L, commonly known as Holy Basil in English or Tulsi in various Indian languages; it is an important medicinal plant in the various traditional and folk systems of medicine in Southeast Asia. Scientific studies have shown it to possess anti-inflammatory, anti-analgesic, anti-pyretic, anti-diabetic, hepato-protective, hypolipidemic, anti-stress, and immunomodulatory activities. It has been found to prevent chemical-induced skin, liver, oral., and lung cancers and mediates these effects by increasing the anti-oxidant activity, altering the gene expressions, inducing apoptosis, and inhibiting angiogenesis and metastasis.

Radio-protective

The aqueous extract of Tulsi 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. The chemo-preventive and radio-protective properties of Tulsi emphasize aspects that warrant future research to establish its activity and utility in cancer prevention and treatment (Baliga et al., 2013).

Anti-inflammatory

Pre-treatment of RAW 264.7 with luteolin, luteolin-7-glucoside, quercetin, and the isoflavonoid genistein inhibited both the LPS-stimulated TNF-αand interleukin-6 release, whereas eriodictyol and hesperetin only inhibited TNF-αrelease. From the compounds tested luteolin and quercetin were the most potent in inhibiting cytokine production with an IC50 of less than 1 and 5 µM for TNF-αrelease, respectively. Pre-treatment of the cells with luteolin attenuated LPS-induced tyrosine phosphorylation of many discrete proteins. Luteolin inhibited LPS-induced phosphorylation of Akt. Treatment of macrophages with LPS resulted in increased IκB-αphosphorylation and reduced the levels of IκB-α. It was concluded that luteolin inhibits protein tyrosine phosphorylation, nuclear factor-κB-mediated gene expression and pro-inflammatory cytokine production in murine macrophages (Xagorari et al., 2001).

Luteolin (Lut) possesses significant anti-inflammatory activity in well established models of acute and chronic inflammation, such as xylene-induced ear edema in mice (ED50= 107 mg/ kg), carrageenin-induced swellingof the ankle, acetic acid-induced pleurisy and croton oil-induced gaseous pouch granuloma in rats. Its combined immunostimulatory and anti-inflammatory activity, and inhibitory effect upon immediate hypersensitive response provide the pharmacologic bases for the beneficial effects of Lut in the treatment of chronic bronchitis (Chen et al., 1986).

Anti-inflammatory; Lung

Luteolin dose-dependently inhibited the expression and production of nitric oxide (NO) and prostaglandin E2 (PGE2), as well as the expression of inducible NO synthase (iNOS), cyclooxygenase-2 (COX-2), tumor necrosis factor-alpha (TNF-α), and interleukin-6 (IL-6). Luteolin also reduced the DNA binding activity of nuclear factor-kappa B (NF-κB) in LPS-activated macrophages. Moreover, luteolin blocked the degradation of IκB-α and nuclear translocation of NF-κB p65 subunit.

In sum, these data suggest that, by blocking NF-κ>B and AP-1 activation, luteolin acts to suppress the LPS-elicited inflammatory events in mouse alveolar macrophages, and this effect was mediated, at least in part, by inhibiting the generation of reactive oxygen species. These observations suggest a possible therapeutic application of this agent for treating inflammatory disorders in the lung (Chen et al., 2007).

Anti-inflammatory; Neuroinflammation

Pre-treatment of primary murine microglia and BV-2 microglial cells with luteolin inhibited LPS-stimulated IL-6 production at both the mRNA and protein levels. Whereas luteolin had no effect on the LPS-induced increase in NF-κB DNA binding activity, it markedly reduced AP-1 transcription factor binding activity. To determine whether luteolin might have similar effects in vivo, mice were provided drinking water supplemented with luteolin for 21 days and then they were injected i.p. with LPS. Luteolin consumption reduced LPS-induced IL-6 in plasma 4 hours after injection. Taken together, these data suggest luteolin inhibits LPS-induced IL-6 production in the brain by inhibiting the JNK signaling pathway and activation of AP-1 in microglia. Thus, luteolin may be useful for mitigating neuroinflammation (Jang et al., 2008).

Colon Cancer

Activities of CDK4 and CDK2 decreased within 2 hours after luteolin treatment, with a 38% decrease in CDK2 activity (P < 0.05) observed in cells treated with 40 µmol/l luteolin. Luteolin inhibited CDK2 activity in a cell-free system, suggesting that it directly inhibits CDK2.

tLuteolin promoted G2/M arrest at 24 hours post-treatment  by down-regulating cyclin B1 expression and inhibiting cell division cycle (CDC)2 activity. Luteolin promoted apoptosis with increased activation of caspases 3, 7, and 9 and enhanced poly(ADP-ribose) polymerase cleavage and decreased expression of p21CIP1/WAF1, survivin, Mcl-1, Bcl-xL, and Mdm-2. Decreased expression of these key antiapoptotic proteins could contribute to the increase in p53-independent apoptosis that was observed in HT-29 cells. Lim et al., (2007) demonstrated that luteolin promotes both cell-cycle arrest and apoptosis in the HT-29 colon cancer cell line, providing insight about the mechanisms underlying its anti-tumorigenic activities.

Pancreatic Cancer; Chemotherapy

Simultaneous treatment or pre-treatment (0, 6, 24 and 42 hours) of flavonoids and chemotherapeutic drugs and various concentrations (0-50µM) were assessed using the MTS cell proliferation assay. Simultaneous treatment with either flavonoid (0,13, 25 or 50µM) and chemotherapeutic drugs 5-fluorouracil (5-FU, 50µM) or gemcitabine (Gem, 10µM) for 60h 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-3βand NF-κB p65 and increased pro-apoptotic cytosolic cytochrome c. Pre-treatment of human pancreatic cancer cells BxPC-3 with low concentrations of Lut effectively aid in the anti-proliferative activity of chemotherapeutic drugs (Johnson et al., 2013).

Ovarian Cancer

Luteolin has been found to repress NF-kappaB (NF-κ>B, a pro-inflammatory transcription factor) and inhibit pro-inflammatory cytokines such as TNF-αand IL-6. Additionally, it has been shown to stabilize p53 protein, sensitize TRAIL (TNF receptor apoptosis-inducing ligand) induced apoptosis, and prevent or delay chemotherapy-resistance.

Recent studies further indicate that luteolin potently inhibits VEGF production and suppresses ovarian cancer cell metastasis in vitro. Lastly, oridonin and wogonin were suggested to suppress ovarian CSCs as is reflected by down-regulation of the surface marker EpCAM. Unlike NSAIDS (non-steroid anti-inflammatory drugs), well documented clinical data for phyto-active compounds are lacking. In order to evaluate objectively the potential benefit of these compounds in the treatment of ovarian cancer, strategically designed, large scale studies are warranted (Chen et al., 2012).

Chemo-sensitizer

The sensitization effect of luteolin on cisplatin-induced apoptosis is p53 dependent, as such effect is only found in p53 wild-type cancer cells but not in p53 mutant cancer cells. Moreover, knockdown of p53 by small interfering RNA made p53 wild-type cancer cells resistant to luteolin and cisplatin. Second, Shi et al., (2007) observed a significant increase of p53 protein level in luteolin-treated cancer cells without increase of p53 mRNA level, indicating the possible effect of luteolin on p53 posttranscriptional regulation.

In summary, data from this study reveal a novel molecular mechanism involved in the anti-cancer effect of luteolin and support its potential clinical application as a chemo-sensitizer in cancer therapy.

Breast Cancer; TAM Chemo-sensitizer

This study found that the level of cyclin E2 (CCNE2) mRNA was higher in tumor cells (4.89-fold, (∗)P=0.005) than in normal paired tissue samples as assessed using real-time reverse-transcriptase polymerase chain reaction (RT-PCR) analysis (n=257). Further, relatively high levels of CCNE2 protein expression were detected in tamoxifen-resistant (TAM-R) MCF-7 cells.

These results showed that the level of CCNE2 protein expression was specifically inhibited in luteolin-treated (5µM) TAM-R cells, either in the presence or absence of 4-OH-TAM (100nM). Combined treatment with 4-OH-TAM and luteolin synergistically sensitized the TAM-R cells to 4-OH-TAM. The results of this study 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).

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.


Chen CY, Peng WH, Tsai KD and Hsu SL. (2007). Luteolin suppresses inflammation-associated gene expression by blocking NF-κB and AP-1 activation pathway in mouse alveolar macrophages. Life Sciences, 81(23-24):1602-1614. doi:10.1016/j.lfs.2007.09.028


Chen MZ, Jin WZ, Dai LM, Xu SY. (1986). Effect of luteolin on inflammation and immune function. Chinese Journal of Pharmacology and Toxicology, 1986-01.


Chen SS, Michael A, Butler-Manuel SA. (2012). Advances in the treatment of ovarian cancer: a potential role of anti-inflammatory phytochemicals. Discov Med, 13(68):7-17.


Jang S, Kelley KW, Johnson RW. (2008). Luteolin reduces IL-6 production in microglia by inhibiting JNK phosphorylation and activation of AP-1. PNAS, 105(21):7534-7539


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, S0278-6915(13)00491-2. doi: 10.1016/j.fct.2013.07.036.


Lim DY, Jeong Y, Tyner Al., Park JHY. (2007). Induction of cell-cycle arrest and apoptosis in HT-29 human colon cancer cells by the dietary compound luteolin. Am J Physiol Gastrointest Liver Physiol, 292: G66-G75. doi:10.1152/ajpgi.00248.2006.


Shi R, Huang Q, Zhu X, et al. (2007). Luteolin sensitizes the anti-cancer effect of cisplatin via c-Jun NH2-terminal kinase-mediated p53 phosphorylation and stabilization. Molecular Cancer Therapeutics, 6(4):1338-1347. doi: 10.1158/1535-7163.MCT-06-0638.


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.


Xagorari A, Papapetropoulos A, Mauromatis A, et al. (2001). Luteolin inhibits an endotoxin-stimulated phosphorylation cascade and pro-inflammatory cytokine production in macrophages. JPET, 296(1):181-187.

Carnosol

Cancer: Breast, prostate, skin, colon, leukemia, stomach

Action: Anti-inflammatrory, anti-angiogenic

Carnosol is found in certain Mediterranean meats, fruits, vegetables, and olive oil. In particular, it is sourced from rosemary (Rosmarinus officinalis (L.)) and desert sage (Salvia pachyphylla (Epling ex Munz)).

Prostate Cancer, Breast Cancer, Skin Cancer, Colon Cancer, Leukemia

One agent, carnosol, has been evaluated for anti-cancer property in prostate, breast, skin, leukemia, and colon cancer with promising results. These studies have provided evidence that carnosol targets multiple deregulated pathways associated with inflammation and cancer that include nuclear factor kappa B (NFκB), apoptotic related proteins, phosphatidylinositol-3-kinase (PI3 K)/Akt, androgen and estrogen receptors, as well as molecular targets. In addition, carnosol appears to be well tolerated in that it has a selective toxicity towards cancer cells versus non-tumorigenic cells and is well tolerated when administered to animals.

This mini-review reports on the pre-clinical studies that have been performed to date with carnosol describing mechanistic, efficacy, and safety/tolerability studies as a cancer chemoprevention and anti-cancer agent (Johnson, 2011).

Literature evidence from animal and cell culture studies demonstrates the anti-cancer potential of rosemary extract, carnosol, carnosic acid, ursolic acid, and rosmarinic acid to suppress the development of tumors in several organs including the colon, breast, liver, stomach, as well as melanoma and leukemia cells (Ngo et al., 2011).

Anti-inflammatory

Treatment with retinoic acid (RA) or carnosol, two structurally unrelated compounds with anti-cancer properties, inhibited phorbol ester (PMA)-mediated induction of activator protein-1 (AP-1) activity and cyclooxygenase-2 (COX-2) expression in human mammary epithelial cells. Treatment with carnosol but not RA blocked increased binding of AP-1 to the COX-2 promoter. Carnosol but not RA inhibited the activation of PKC, ERK1/2, p38, and c-Jun NH2-terminal kinase mitogen-activated protein kinase. Overexpressing c-Jun but not CBP/p300 reversed the suppressive effect of carnosol on PMA-mediated stimulation of COX-2 promoter activity.

Carnosol inhibited the induction of COX-2 by blocking PKC signaling and thereby the binding of AP-1 to the CRE of the COX-2 promoter. Taken together, these results show that small molecules can block the activation of COX-2 transcription by distinct mechanisms (Subbaramaiah, 2002).

Breast Cancer

Two rosemary components, carnosol and ursolic acid, appear to be partly responsible for the anti-tumorigenic activity of rosemary. Supplementation of diets for 2 weeks with rosemary extract (0.5% by wt) but not carnosol (1.0%) or ursolic acid (0.5%) resulted in a significant decrease in the in vivo formation of rat mammary DMBA-DNA adducts, compared to controls. When injected intraperitoneally (i.p.) for 5 days at 200 mg/kg body wt, rosemary and carnosol, but not ursolic acid, significantly inhibited mammary adduct formation by 44% and 40%, respectively, compared to controls. Injection of this dose of rosemary and carnosol was associated with a significant 74% and 65% decrease, respectively, in the number of DMBA-induced mammary adenocarcinomas per rat, compared to controls. Ursolic acid injection had no effect on mammary tumorigenesis.

Therefore, carnosol is one rosemary constituent that can prevent DMBA-induced DNA damage and tumor formation in the rat mammary gland, and, thus, has potential for use as a breast cancer chemopreventative agent (Singletary et al., 1996).

Anti-angiogenic

The anti-angiogenic activity of carnosol and carnosic acid could contribute to the chemo-preventive, anti-tumoral and anti-metastatic activities of rosemary extracts and suggests that there is potential in the treatment of other angiogenesis-related malignancies (L-pez-JimŽnez et al., 2013).

References:

Johnson JJ. (2011). Carnosol: A promising anti-cancer and anti-inflammatory agent. Cancer Letters, 305(1):1-7. doi:10.1016/j.canlet.2011.02.005.


L-pez-JimŽnez A, Garc'a-Caballero M, Medina Mç, Quesada AR. (2013). Anti-angiogenic properties of carnosol and carnosic acid, two major dietary compounds from rosemary. Eur J Nutr, 52(1):85-95. doi: 10.1007/s00394-011-0289-x.


Ngo SN, Williams DB, Head RJ. (2011). Rosemary and cancer prevention: preclinical perspectives. Crit Rev Food Sci Nutr, 51(10):946-54. doi: 10.1080/10408398.2010.490883.


Singletary K, MacDonald C & Wallig M. (1996). Inhibition by rosemary and carnosol of 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumorigenesis and in vivo DMBA-DNA adduct formation. Cancer Letters, 104(1):43-8. doi: 10.1016/0304-3835(96)04227-9


Subbaramaiah K, Cole PA, Dannenberg AJ. (2002). Retinoids and Carnosol Suppress Cyclooxygenase-2 Transcription by CREB-binding Protein/p300-dependent and -independent Mechanisms. Cancer Res, 62:2522

Carnosol

Cancer: Breast, prostate, skin, colon, leukemia, stomach

Action: Anti-inflammatrory, anti-angiogenic

Carnosol is found in certain Mediterranean meats, fruits, vegetables, and olive oil. In particular, it is sourced from rosemary (Rosmarinus officinalis (L.)) and desert sage (Salvia pachyphylla (Epling ex Munz)).

Prostate Cancer, Breast Cancer, Skin Cancer, Colon Cancer, Leukemia

One agent, carnosol, has been evaluated for anti-cancer property in prostate, breast, skin, leukemia, and colon cancer with promising results. These studies have provided evidence that carnosol targets multiple deregulated pathways associated with inflammation and cancer that include nuclear factor kappa B (NFκB), apoptotic related proteins, phosphatidylinositol-3-kinase (PI3 K)/Akt, androgen and estrogen receptors, as well as molecular targets. In addition, carnosol appears to be well tolerated in that it has a selective toxicity towards cancer cells versus non-tumorigenic cells and is well tolerated when administered to animals.

This mini-review reports on the pre-clinical studies that have been performed to date with carnosol describing mechanistic, efficacy, and safety/tolerability studies as a cancer chemoprevention and anti-cancer agent (Johnson, 2011).

Literature evidence from animal and cell culture studies demonstrates the anti-cancer potential of rosemary extract, carnosol, carnosic acid, ursolic acid, and rosmarinic acid to suppress the development of tumors in several organs including the colon, breast, liver, stomach, as well as melanoma and leukemia cells (Ngo et al., 2011).

Anti-inflammatory

Treatment with retinoic acid (RA) or carnosol, two structurally unrelated compounds with anti-cancer properties, inhibited phorbol ester (PMA)-mediated induction of activator protein-1 (AP-1) activity and cyclooxygenase-2 (COX-2) expression in human mammary epithelial cells. Treatment with carnosol but not RA blocked increased binding of AP-1 to the COX-2 promoter. Carnosol but not RA inhibited the activation of PKC, ERK1/2, p38, and c-Jun NH2-terminal kinase mitogen-activated protein kinase. Overexpressing c-Jun but not CBP/p300 reversed the suppressive effect of carnosol on PMA-mediated stimulation of COX-2 promoter activity.

Carnosol inhibited the induction of COX-2 by blocking PKC signaling and thereby the binding of AP-1 to the CRE of the COX-2 promoter. Taken together, these results show that small molecules can block the activation of COX-2 transcription by distinct mechanisms (Subbaramaiah, 2002).

Breast Cancer

Two rosemary components, carnosol and ursolic acid, appear to be partly responsible for the anti-tumorigenic activity of rosemary. Supplementation of diets for 2 weeks with rosemary extract (0.5% by wt) but not carnosol (1.0%) or ursolic acid (0.5%) resulted in a significant decrease in the in vivo formation of rat mammary DMBA-DNA adducts, compared to controls. When injected intraperitoneally (i.p.) for 5 days at 200 mg/kg body wt, rosemary and carnosol, but not ursolic acid, significantly inhibited mammary adduct formation by 44% and 40%, respectively, compared to controls. Injection of this dose of rosemary and carnosol was associated with a significant 74% and 65% decrease, respectively, in the number of DMBA-induced mammary adenocarcinomas per rat, compared to controls. Ursolic acid injection had no effect on mammary tumorigenesis.

Therefore, carnosol is one rosemary constituent that can prevent DMBA-induced DNA damage and tumor formation in the rat mammary gland, and, thus, has potential for use as a breast cancer chemopreventative agent (Singletary et al., 1996).

Anti-angiogenic

The anti-angiogenic activity of carnosol and carnosic acid could contribute to the chemo-preventive, anti-tumoral and anti-metastatic activities of rosemary extracts and suggests that there is potential in the treatment of other angiogenesis-related malignancies (L-pez-JimŽnez et al., 2013).

References:

Johnson JJ. (2011). Carnosol: A promising anti-cancer and anti-inflammatory agent. Cancer Letters, 305(1):1-7. doi:10.1016/j.canlet.2011.02.005.


L-pez-JimŽnez A, Garc'a-Caballero M, Medina Mç, Quesada AR. (2013). Anti-angiogenic properties of carnosol and carnosic acid, two major dietary compounds from rosemary. Eur J Nutr, 52(1):85-95. doi: 10.1007/s00394-011-0289-x.


Ngo SN, Williams DB, Head RJ. (2011). Rosemary and cancer prevention: preclinical perspectives. Crit Rev Food Sci Nutr, 51(10):946-54. doi: 10.1080/10408398.2010.490883.


Singletary K, MacDonald C & Wallig M. (1996). Inhibition by rosemary and carnosol of 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat mammary tumorigenesis and in vivo DMBA-DNA adduct formation. Cancer Letters, 104(1):43-8. doi: 10.1016/0304-3835(96)04227-9


Subbaramaiah K, Cole PA, Dannenberg AJ. (2002). Retinoids and Carnosol Suppress Cyclooxygenase-2 Transcription by CREB-binding Protein/p300-dependent and -independent Mechanisms. Cancer Res, 62:2522

Baicalin & Baicalein

Cancer:
Myeloma, liver, colorectal., breast, prostate, oral., hepatoma, ovarian

Action: Anti-cancer, cardiovascular disease, cytostatic, cardio-protective against Doxorubicin, anti-inflammatory, angiogenesis

Baicalin and baicalein are naturally occurring flavonoids that are found in the roots and leaves of some Chinese medicinal plants (including Scutellaria radix, Scutellaria rivularis (Benth.); Scutellaria baicalensis (Georgi) and Scutellaria lateriflora (L.)) are thought to have anti-oxidant activity and possible anti-angiogenic, anti-cancer, anxiolytic, anti-inflammatory and neuroprotective activities. In particular, Scutellaria baicalensis is one of the most popular and multi-purpose herbs used in China traditionally for treatment of inflammation, hypertension, cardiovascular diseases, and bacterial and viral infections (Ye et al., 2002; Zhang et al., 2011a).

Anti-cancer

Accumulating evidence demonstrates that Scutellaria also possesses potent anti-cancer activities. The bioactive components of Scutellaria have been confirmed to be flavones, wogonin, baicalein and baicalin. These phytochemicals are not only cytostatic but also cytotoxic to various human tumor cell lines in vitro and inhibit tumor growth in vivo. Most importantly, they show almost no or minor toxicity to normal epithelial and normal peripheral blood and myeloid cells. The anti-tumor functions of these flavones are largely due to their abilities to scavenge oxidative radicals, to attenuate NF-kappaB activity, to inhibit several genes important for regulation of the cell-cycle, to suppress COX-2 gene expression and to prevent viral infections (Li, 2008).

Multiple Myeloma

In the search for a more effective adjuvant therapy to treat multiple myeloma (MM), Ma et al. (2005) investigated the effects of the traditional Chinese herbal medicines Huang-Lian-Jie-Du-Tang (HLJDT), Gui-Zhi-Fu-Ling-Wan (GZFLW), and Huang-Lian-Tang (HLT) on the proliferation and apoptosis of myeloma cells. HLJDT inhibited the proliferation of myeloma cell lines and the survival of primary myeloma cells, especially MPC-1- immature myeloma cells, and induced apoptosis in myeloma cell lines via a mitochondria-mediated pathway by reducing mitochondrial membrane potential and activating caspase-9 and caspase-3.

Further experiments confirmed that Scutellaria radix was responsible for the suppressive effect of HLJDT on myeloma cell proliferation, and the baicalein in Scutellaria radix showed strong growth inhibition and induction of apoptosis in comparison with baicalin or wogonin. Baicalein as well as baicalin suppressed the survival in vitro of MPC-1- immature myeloma cells rather than MPC-1+ myeloma cells from myeloma patients.

Baicalein inhibited the phosphorylation of IkB-alpha, which was followed by decreased expression of the IL-6 and XIAP genes and activation of caspase-9 and caspase-3. Therefore, HLJDT and Scutellaria radix have an anti-proliferative effect on myeloma cells, especially MPC-1- immature myeloma cells, and baicalein may be responsible for the suppressive effect of Scutellaria radix by blocking IkB-alpha degradation (Ma, 2005).

Hepatoma

The effects of the flavonoids from Scutellaria baicalensis Georgi (baicalein, baicalin and wogonin) in cultured human hepatoma cells (Hep G2, Hep 3B and SK-Hep1) were compared by MTT assay and flow cytometry. All three flavonoids dose-dependently decreased the cell viabilities accompanying the collapse of mitochondrial membrane potential and the depletion of glutathione content. However, the influence of baicalein, baicalin or wogonin on cell-cycle progression was different.

All three flavonoids resulted in prominent increase of G2/M population in Hep G2 cells, whereas an accumulation of sub G1 (hypoploid) peak in Hep 3B cells was observed. In SK-Hep1 cells, baicalein and baicalin resulted in a dramatic boost in hypoploid peak, but wogonin mainly in G1 phase accumulation. These data, together with the previous findings in other hepatoma cell lines, suggest that baicalein, baicalin and wogonin might be effective candidates for inducing apoptosis or inhibiting proliferation in various human hepatoma cell lines (Chang, 2002).

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

Interestingly, baicalein by itself induced an increase in H(2)O(2) generation and the subsequent NF-kappaB activation; furthermore, it effectively inhibited the transforming growth factor-beta(1) (TGF-beta(1))-induced caspase-3 activation and cell apoptosis. Results suggest that alisol B acetate and saikosaponin-d induced cell apoptosis through the caspase-3-dependent and -independent pathways, respectively. Instead of inducing apoptosis, baicalein inhibits TGF-beta(1)-induced apoptosis via increase in cellular H(2)O(2) formation and NF-kappaB activation in human hepatoma Hep3B cells (Chou, Pan, Teng & Guh, 2003).

Ovarian Cancer

Ovarian cancer is one of the primary causes of death for women all through the Western world. Two kinds of ovarian cancer (OVCAR-3 and CP-70) cell lines and a normal ovarian cell line (IOSE-364) were selected to be investigated in the inhibitory effect of baicalin and baicalein on cancer cells. Largely, baicalin and baicalein inhibited ovarian cancer cell viability in both ovarian cancer cell lines with LD50 values in the range of 45-55 µM for baicalin and 25-40 µM for baicalein. On the other hand, both compounds had fewer inhibitory effects on normal ovarian cells viability with LD50 values of 177 µM for baicalin and 68 µM for baicalein.

Baicalin decreased expression of VEGF (20 µM), cMyc (80 µM), and NFkB (20 µM); baicalein decreased expression of VEGF (10 µM), HIF-1α (20 µM), cMyc (20 µM), and NFkB (40 µM). Therefore baicalein is more effective in inhibiting cancer cell viability and expression of VEGF, HIF-1α, cMyc, and NFκB in both ovarian cancer cell lines. It seems that baicalein inhibited cancer cell viability through the inhibition of cancer promoting genes expression including VEGF, HIF-1α, cMyc, and NFκB.

Overall, this study showed that baicalein and baicalin significantly inhibited the viability of ovarian cancer cells, while generally exerting less of an effect on normal cells. They have potential for chemoprevention and treatment of ovarian cancers (Chen, 2013).

Breast Cancer

Baicalin was found to be a potent inhibitor of mammary cell line MCF-7 and ductal breast epithelial tumor cell line T-47D proliferation, as well as having anti-proliferative effects on other cancer types such as the human head and neck cancer epithelial cell lines CAL-27 and FaDu. Overall, baicalin inhibited the proliferation of human breast cancer cells and CAL-27 and FaDu cells with effective potency (Franek, 2005).

Breast Cancer, Cell Invasion

The effect of Baicalein on cell viability of the human breast cancer MDA-MB-231 cell line was tested by MTT. 50, 100 µmol·L-1 of Baicalein inhibited significantly cell invasion(P0.01) and migration(P0.01) compared with control groups. The inhibitory rates were 50% and 77% in cell migration and 15% and 44% in cell invasion, respectively. 50 µmol·L-1 of Baicalein significantly inhibited the level of MMP 2 expression. 100 µmol·L-1 of Baicalein significantly inhibited the level of MMP 9 and uPA expressions.

Baicalein inhibits invasion and migration of MDA-MB-231 cells. The mechanisms may be involved in the direct inhibition of cell invasion and migration abilities, and the inhibition of MMP 2, MMP 9, and uPA expressions (Wang et al., 2010).

The proliferation of MDA-MB-231 cell line human breast adenocarcinoma was inhibited by baicalin in a dose-and time-dependent manner and the IC50 was 151 µmol/L. The apoptotic rate of the baicalin-treated MDA-MB-231 cells increased significantly at 48 hours. Flow cytometer analysis also revealed that most of the baicalin-treated MDA-MB-231 cells were arrested in the G2/M phase. Typically apoptotic characteristics such as condensed chromatin and apoptotic bodies were observed after being treated with baicalin for 48 hours.

The results of RT-PCR showed that the expression of bax was up-regulated; meanwhile, the expression of bcl-2 was down-regulated. Baicalin could inhibit the proliferation of MDA-MB-231 cells through apoptosis by regulating the expression of bcl-2, bax and intervening in the process of the cell-cycle (Zhu et al., 2008).

Oral Cancer

As an aryl hydrocarbon receptor (AhR) ligand, baicalein at high concentrations blocks AhR-mediated dioxin toxicity. Because AhR had been reported to play a role in regulating the cell-cycle, it is suspected that the anti-cancer effect of baicalein is associated with AhR. The molecular mechanism involved in the anti-cancer effect of baicalein in oral cancer cells HSC-3 has been investigated, including whether such an effect would be AhR-mediated. Results revealed that baicalein inhibited cell proliferation and increased AhR activity in a dose-dependent manner. Cell-cycle was arrested at the G1 phase and the expression of CDK4, cyclin D1, and phosphorylated retinoblastoma (pRb) was decreased.

When cells were pre-treated with LiCl, the inhibitor of GSK-3β, the decrease of cyclin D1 was blocked and the reduction of pRb was recovered. The data indicates that in HSC-3 the reduction of pRb is mediated by baicalein both through activation of AhR and facilitation of cyclin D1 degradation, which causes cell-cycle arrest at the G1 phase, and results in the inhibition of cell proliferation (Cheng, 2012).

Anti-inflammatory

Baicalin has also been examined for its effects on LPS-induced nitric oxide (NO) production and iNOS and COX-2 gene expressions in RAW 264.7 macrophages. The results indicated that baicalin inhibited LPS-induced NO production in a concentration-dependent manner without a notable cytotoxic effect on these cells. The decrease in NO production was consistent with the inhibition by baicalin of LPS-induced iNOS gene expression (Chen, 2001)

Angiogenesis Modulation

The modulation of angiogenesis is one possible mechanism by which baicalin may act in the treatment of cardiovascular diseases. This may be elucidated by investigating the effects of baicalin on the expression of vascular endothelial growth factor (VEGF), a critical factor for angiogenesis. The effects of baicalin and an extract of S. baicalensis on VEGF expression were tested in several cell lines. Both agents induced VEGF expression in all cells without increasing expression of hypoxia-inducible factor-1alpha (HIF-1alpha).

Their ability to induce VEGF expression was suppressed once ERRalpha expression was knocked down by siRNA, or ERRalpha-binding sites were deleted in the VEGF promoter. It was also found that both agents stimulated cell migration and vessel sprout formation from the aorta. These results therefore implicate baicalin and S. baicalensis in angiogenesis by inducing VEGF expression through the activation of the ERRalpha pathway (Zhang, 2011b).

Colon Cancer

The compounds of baicalein and wogonin, derived from the Chinese herb Scutellaria baicalensis, were studied for their effect in suppressing the viability of HT-29 human colon cancer cells. Following treatment with baicalein or wogonin, several apoptotic events were observed, including DNA fragmentation, chromatin condensation and increased cell-cycle arrest at the G1 phase. Baicalein and wogonin decreased Bcl-2 expression, whereas the expression of Bax was increased in a dose-dependent manner when compared to the control.

The results indicated that baicalein induced apoptosis via Akt activation, in a p53-dependent manner, in HT-29 colon cancer cells. Baicalein may serve as a chemo-preventive, or therapeutic, agent for HT-29 colon cancer (Kim et al., 2012).

Cardio-protective

The cardiotoxicity of doxorubicin limits its clinical use in the treatment of a variety of malignancies. Previous studies suggest that doxorubicin-associated cardiotoxicity is mediated by reactive oxygen species (ROS)-induced apoptosis. Baicalein attenuated phosphorylation of JNK induced by doxorubicin. Co-treatment of cardiomyocytes with doxorubicin and JNK inhibitor SP600125 (10 µM; 24 hours) reduced JNK phosphorylation and enhanced cell survival., suggesting that the baicalein protection against doxorubicin cardiotoxicity was mediated by JNK activation. Baicalein adjunct treatment confers anti-apoptotic protection against doxorubicin-induced cardiotoxicity without compromising its anti-cancer efficacy (Chang et al., 2011).

Prostate Cancer

There are four compounds capable of inhibiting prostate cancer cell proliferation in Scutellaria baicalensis: baicalein, wogonin, neobaicalein, and skullcapflavone. Comparisons of the cellular effects induced by the entire extract versus the four-compound combination produced comparable cell-cycle changes, levels of growth inhibition, and global gene expression profiles (r(2) = 0.79). Individual compounds exhibited anti-androgenic activities with reduced expression of the androgen receptor and androgen-regulated genes. In vivo, baicalein (20 mg/kg/d p.o.) reduced the growth of prostate cancer xenografts in nude mice by 55% at 2 weeks compared with placebo and delayed the average time for tumors to achieve a volume of approximately 1,000 mm(3) from 16 to 47 days (P < 0.001).

Most of the anti-cancer activities of S. baicalensis can be recapitulated with four purified constituents that function in part through inhibition of the androgen receptor signaling pathway (Bonham et al., 2005)

Cancer: Acute lymphocytic leukemia, lymphoma and myeloma

Action: Cell-cycle arrest, induces apoptosis

Scutellaria baicalensis (S.B.) is a widely used Chinese herbal medicine. S.B inhibited the growth of acute lymphocytic leukemia (ALL), lymphoma and myeloma cell lines by inducing apoptosis and cell cycle arrest at clinically achievable concentrations. The anti-proliferative effectwas associated with mitochondrial damage, modulation of the Bcl family of genes, increased level of the CDK inhibitor p27KIP1 and decreased level of c-myc oncogene. HPLC analysis of S.B. showed it contains 21% baicalin and further studies confirmed it was the major anti-cancer component of S.B. Thus, Scutellaria baicalensis should be tested in clinical trials for these hematopoietic malignancies (Kumagai et al., 2007).

References

Bonham M, Posakony J, Coleman I, Montgomery B, Simon J, Nelson PS. (2005). Characterization of chemical constituents in Scutellaria baicalensis with antiandrogenic and growth-inhibitory activities toward prostate carcinoma. Clin Cancer Res, 11(10):3905-14.


Chang WH Chen CH Lu FJ. (2002). Different Effects of Baicalein, Baicalin and Wogonin on Mitochondrial Function, Glutathione Content and cell-cycle Progression in Human Hepatoma Cell Lines. Planta Med, 68(2):128-32. doi: 10.1055/s-2002-20246


Chang WT, Li J, Huang HH, et al. (2011). Baicalein protects against doxorubicin-induced cardiotoxicity by attenuation of mitochondrial oxidant injury .and JNK activation. J Cell Biochem. doi: 10.1002/jcb.23201.


Chen J, Li Z, Chen AY, Ye X, et al. (2013). Inhibitory effect of baicalin and baicalein on ovarian cancer cells. Int J Mol Sci, 14(3):6012-25. doi: 10.3390/ijms14036012.


Chen YC, Shen SC, Chen LG, Lee TJ, Yang LL. (2001). Wogonin, baicalin, and baicalein inhibition of inducible nitric oxide synthase and cyclooxygenase-2 gene expressions induced by nitric oxide synthase inhibitors and lipopolysaccharide. Biochem Pharmacol,61(11):1417-27. doi:10.1016/S0006-2952(01)00594-9


Cheng YH, Li LA, Lin P, et al. (2012). Baicalein induces G1 arrest in oral cancer cells by enhancing the degradation of cyclin D1 and activating AhR to decrease Rb phosphorylation. Toxicol Appl Pharmacol, 263(3):360-7. doi: 10.1016/j.taap.2012.07.010.


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


Franek KJ, Zhou Z, Zhang WD, Chen WY. (2005). In vitro studies of baicalin alone or in combination with Salvia miltiorrhiza extract as a potential anti-cancer agent. Int J Oncol, 26(1):217-24.


Kim SJ, Kim HJ, Kim HR, et al. (2012). Anti-tumor actions of baicalein and wogonin in HT-29 human colorectal cancer cells. Molecular Medicine Reports, 6(6):1443-1449. doi: 10.3892/mmr.2012.1085.


Li-Weber M. (2009). New therapeutic aspects of flavones: The anti-cancer properties of Scutellaria and its main active constituents Wogonin, Baicalein and Baicalin. Cancer Treat Rev, 35(1):57-68. doi: 10.1016/j.ctrv.2008.09.005.


Ma Z, Otsuyama K, Liu S, et al. (2005). Baicalein, a component of Scutellaria radix from Huang-Lian-Jie-Du-Tang (HLJDT), leads to suppression of proliferation and induction of apoptosis in human myeloma cells. Blood, 105(8):3312-8. doi:10.1182/blood-2004-10-3915.


Wang Xf, Zhou Qm, Su Sb. (2010). Experimental study on Baicalein inhibiting the invasion and migration of human breast cancer cells. Zhong Guo Yao Li Xue Tong Bao, 26(6): 745-750.


Zhang XW, Li WF, Li WW, et al. (2011a). Protective effects of the aqueous extract of Scutellaria baicalensis against acrolein-induced oxidative stress in cultured human umbilical vein endothelial cells. Pharm Biol, 49(3): 256–261. doi:10.3109/13880209.2010.501803.


Ye F, Xui L, Yi J, Zhang, W, Zhang DY. (2002). Anti-cancer activity of Scutellaria baicalensis and its potential mechanism. J Altern Complement Med, 8(5):567-72.


Zhang K, Lu J, Mori T, et al. (2011b). Baicalin increases VEGF expression and angiogenesis by activating the ERR{alpha}/PGC-1{alpha} pathway.[J]. Cardiovascular Research, 89(2):426-435.


Zhu Gq, Tang Lj, Wang L, Su Jj, et al. (2008). Study on Baicalin Induced Apoptosis of Human Breast Cancer Cell Line MDA-MB-231. An Hui Zhong Yi Xue Yuan Xue Bao, 27(2):20-23

Kumagai T, et al. (2007) Scutellaria baicalensis, a herbal medicine: Anti-proliferative and apoptotic activity against acute lymphocytic leukemia, lymphoma and myeloma cell lines. Leukemia Research 31 (2007) 523-530

Quercetin

Cancer: Leukemia, prostate

Action: MDR, apoptosis-inducing

Quercetin is a plant-derived flavonol found in many fruits, vegetables, leaves and grains. It is also found in red wine.

MDR/ Apoptotic-inducing

Natural products from plants such as flavonoids are potential drugs to overcome multi-drug resistance (MDR) in cancer treatments. Quercetin exhibits cytotoxicity against erythroleukemic cells: IC50 are 11.0 +/- 2.0 micromol/L and 5.0 +/- 0.4 micromol/L for K562 and K562/adr, respectively. Quercetin induces cell death via apoptosis in both K562 and K562/adr cells and does not inhibit Pgp-mediated efflux of 99mTc-MIBI. Quercetin (10 micromol/L, 3 h) and etoposide (100 micromol/L, 24 hours) induce similar levels of apoptosis in K562 and K562/adr cells.

Quercetin induces an increase followed by a decrease in inner mitochondrial membrane potential   |DeltaPsim| value depending on its concentration. A decrease in the |DeltaPsim| value is associated with an increase in the percentage of early apoptotic cells.

It is clearly shown that quercetin results in a spontaneous DeltaPsim change during apoptotic induction. Therefore, quercetin is potentially an apoptotic-inducing agent, which reacts at the mitochondrial level (Kothan et al., 2004).

MDR

Expression of the MDR1 gene, which encodes P-glycoprotein, is increased under some stress conditions. It has been reported that quercetin, a bioflavonoid, inhibits the expression of heat-shock proteins. The effects of quercetin have been identified on the MDR1 gene expression in the human hepatocarcinoma cells line, HepG2. The increase of P-glycoprotein synthesis and MDR1 mRNA accumulation caused by exposure to arsenite were inhibited by quercetin. Although many drugs that prevent the P-glycoprotein function have been reported, this is the first report to describe the inhibition of MDR1 expression by a reagent (Kioka et al., 1992).

Leukemia

Leukemia cells were treated with quercetin, after which apoptosis, Mcl-1 expression, and Bax activation and translocation were evaluated. Quercetin-induced apoptosis was accompanied by Mcl-1 down-regulation and Bax conformational change and mitochondrial translocation that triggered cytochrome c release. In vivo administration of quercetin attenuated tumor growth in U937 xenografts. The TUNEL-positive apoptotic cells in tumor sections increased in quercetin-treated mice as compared with controls.

These data suggest that quercetin may be useful for the treatment of leukemia by preferentially inducing apoptosis in leukemia versus normal hematopoietic cells through a process involving Mcl-1 down-regulation, which, in turn, potentiates Bax activation and mitochondrial translocation, culminating in apoptosis (Cheng et al., 2010).

Prostate Cancer

The anti-angiogenic activity of quercetin was probed using ex vivo, in vivo and in vitro models. Angiogenesis is a crucial step in the growth and metastasis of cancers, since it enables the growing tumor to receive oxygen and nutrients. Quercetin (20 mg/kg/d) significantly reduced the volume and the weight of solid tumors in prostate xenograft mouse model, indicating that quercetin inhibited tumorigenesis by targeting angiogenesis.

Furthermore, quercetin reduced the cell viability and induced apoptosis in prostate cancer cells, which were correlated with the down-regulation of AKT, mTOR and P70S6K expressions. Collectively, these results suggest that quercetin inhibits tumor growth and angiogenesis by targeting VEGF-R2 regulated AKT/mTOR/P70S6K signaling pathway, and could be used as a potential drug candidate for cancer therapy (Pratheeshkumar et al., 2012).

References

Cheng SP, Gao N, Zhang Z, et al. (2010). Quercetin Induces Tumor-Selective Apoptosis through Down-regulation of Mcl-1 and Activation of Bax. Clin Cancer Res, 16(23):5679-91. doi: 10.1158/1078-0432.CCR-10-1565


Kioka N, Hosokawa N, Komano T, Hirayoshi K, Nagate K, Ueda K. (1992). Quercetin, a bioflavonoid, inhibits the increase of human Multi-drug resistance gene (< i> MDR1</i>) expression caused by arsenite. FEBS Lett, 301(3):307-9.


Kothan S, Dechsupa S, Leger G, et al. (2004). Spontaneous mitochondrial membrane potential change during apoptotic induction by quercetin in K562 and K562/adr cells. Can J Physiol Pharmacol, 82(12):1084-90.


Pratheeshkumar P, Budhraja A, et al. (2012). Quercetin inhibits angiogenesis mediated human prostate tumor growth by targeting VEGFR- 2 regulated AKT/mTOR/P70S6K signaling pathways. PLoS One, 7(10):e47516. doi: 10.1371/journal.pone.0047516.

Emodin (See also Aloe-Emodin)

Cancer:
Breast, colon, liver, chemotherapy, myeloma, oral., pancreatic, hepatocellular carcinoma, lung, leukemia

Action: MDR-1, cell-cycle arrest

Emodin is an active natural anthraquinone derivative component of a traditional Chinese and Japanese medicine isolated from the root and rhizomes of Rheum palmatum L., Senna obtusifolia [(L.) H.S.Irwin & Barneby], Fallopia japonica [Houtt. (Ronse Decr.)], Kalimeris indica (L.) Sch.Bip., Ventilago madraspatana (Gaertn.), Rumex nepalensis (Spreng.), Fallopia multiflora [(Thunb.) Haraldson], Cassia occidentalis [(L.) Link], Senna siamea [(Lam.) Irwin et Barneby] and Acalypha australis (L.).

Aloe-emodin is an active natural anthraquinone derivative, and is found in the roots and rhizomes of numerous Chinese medicinal herbs (including Rheum palmatum L) and exhibits anti-cancer effects on many types of human cancer cell lines.

Administration of rhubarb (Emodin) can effectively reverse severe acute pancreatitis (SAP) by regulating the levels of IL-15 and IL-18 (Yu & Yang, 2013).

Pancreatic Cancer

Emodin is a tyrosine kinase inhibitor that has an inhibitory effect on mammalian cell-cycle modulation in specific oncogene-overexpressing cells. Recently, there has been great progress in the preclinical study of the anti-cancer mechanisms of emodin. A recent study revealed that emodin has therapeutic effects on pancreatic cancer through various anti-tumor mechanisms. Notably, the therapeutic efficacy of emodin in combination with chemotherapy was found to be higher than the comparable single chemotherapeutic regime, and the combination therapy also exhibited fewer side-effects (Wei et al., 2013).

Hepatocellular Carcinoma, Pancreatic, Breast, Colorectal and Lung Cancers, and Leukemia

Emodin is found as an active ingredient in different Chinese herbs including Rheum palmatum and Polygonam multiflorum, and has diuretic, vasorelaxant, anti-bacterial., anti-viral., anti-ulcerogenic, anti-inflammatory, and anti-cancer effects. The anti-inflammatory effects of emodin have been exhibited in various in vitro as well as in vivo models of inflammation including pancreatitis, arthritis, asthma, atherosclerosis and glomerulonephritis. As an anti-cancer agent, emodin has been shown to suppress the growth of various tumor cell lines including hepatocellular carcinoma, pancreatic, breast, colorectal., leukemia, and lung cancers. Emodin is a pleiotropic molecule capable of interacting with several major molecular targets including NF-κB, casein kinase II, HER2/neu, HIF-1α, AKT/mTOR, STAT3, CXCR4, topoisomerase II, p53, p21, and androgen receptors which are involved in inflammation and cancer (Shrimali et al., 2013).

Hepatocellular Carcinoma

It has been found that emodin induces apoptotic responses in the human hepatocellular carcinoma cell lines (HCC) Mahlavu, PLC/PRF/5 and HepG2. The addition of emodin to these three cell lines led to inhibition of growth in a time-and dose-dependent manner. Emodin generated reactive oxygen species (ROS) in these cells which brought about a reduction of the intracellular mitochondrial transmembrane potential (ΔΨ m), followed by the activation of caspase–9 and caspase–3, leading to DNA fragmentation and apoptosis.

Preincubation of hepatoma cell lines with the hydrogen peroxide-scavenging enzyme, catalase (CAT) and cyclosporin A (CsA), partially inhibited apoptosis. These results demonstrate that enhancement of generation of ROS, DeltaPsim disruption and caspase activation may be involved in the apoptotic pathway induced by emodin (Jing et al., 2002).

Colon Cancer

In in vitro study, emodin induced cell morphological changes, decreased the percentage of viability, induced G2/M phase arrest and increased ROS and Ca(2+) productions as well as loss of mitochondrial membrane potential (ΔΨ(m)) in LS1034 cells. Emodin-triggered apoptosis was also confirmed by DAPI staining and these effects are concentration-dependent.

In in vivo study, emodin effectively suppressed tumor growth in tumor nude mice xenografts bearing LS1034. Overall, the potent in vitro and in vivo anti-tumor activities of emodin suggest that it might be developed for treatment of colon cancer in the future (Ma et al., 2012).

Myeloid Leukemia

It has been shown that emodin significantly induces cytotoxicity in the human myeloma cells through the elimination of myeloid cell leukemia 1 (Mcl-1). Emodin inhibited interleukin-6–induced activation of Janus-activated kinase 2 (JAK2) and phosphorylation of signal transducer and activator of transcription 3 (STAT3), followed by the decreased expression of Mcl-1. Activation of caspase-3 and caspase-9 was triggered by emodin, but the expression of other anti-apoptotic Bcl-2 family members, except Mcl-1, did not change in the presence of emodin. To clarify the importance of Mcl-1 in emodin-induced apoptosis, the Mcl-1 expression vector was introduced into the human myeloma cells by electroporation. Induction of apoptosis by emodin was almost abrogated in Mcl-1–overexpressing myeloma cells as the same level as in parental cells, which were not treated with emodin. Emodin therefore inhibits interleukin-6–induced JAK2/STAT3 pathway selectively and induces apoptosis in myeloma cells via down-regulation of Mcl-1, which is a good target for treating myeloma. Taken together, these results show emodin as a new potent anti-cancer agent for the treatment of multiple myeloma patients (Muto et al., 2007).

Breast Cancer; Block HER-2

The mechanism by which emodin prevents breast cancer is unknown; however the product of the HER-2/neu proto-oncogene, HER2 has been proposed to be involved. The product of the HER-2/neu proto-oncogene, HER2, is the second member of the human epidermal growth factor receptor (HER) family of tyrosine kinase receptors and has been suggested to be a ligand orphan receptor. Amplification of the HER2 gene and overexpression of the HER2 protein induces cell transformation and has been demonstrated in 10% to 40% of human breast cancer. HER2 overexpression has been suggested to associate with tumor aggressiveness, prognosis and responsiveness to hormonal and cytotoxic agents in breast cancer patients. These findings indicate that HER2 is an appropriate target for tumor-specific therapies.

A number of approaches have been investigated: (1) a humanized monoclonal antibody against HER2, rhuMAbHER2 (trastuzumab), which is already approved for clinical use in the treatment of patients with metastatic breast cancer; (2) tyrosine kinase inhibitors, such as emodin, which block HER2 phosphorylation and its intracellullar signaling; (3) active immunotherapy, such as vaccination; and (4) heat shock protein (Hsp) 90-associated signal inhibitors, such as radicicol derivatives, which induce degradation of tyrosine kinase receptors, such as HER2 (Kurebayashi, 2001).

MDR

The effects of emodin on the nucleoside transport and multi-drug resistance in cancer cells has also been investigated. Nucleoside transport inhibition was determined by thymidine incorporation assay. The cytotoxicity to cancer cells was determined by MTT assay. The pump efflux activity and the expression of P glycoprotein were examined by flow cytometric assay. Emodin was active in the inhibition of nucleoside transport, with an IC 50 value of 9 9 µmol·L -1. Emodin markedly enhanced the cytotoxicity of 5 FU, MMC and MTX against human hepatoma BEL 7402 cells and partly reversed the multi-drug resistance in human breast cancer MCF 7/Adr cells.

Emodin inhibited P-gp pump efflux activity and reduced the expression of P gp in MCF 7/Adr cells. These findings provide a biological basis for the application of emodin as a biochemical modulator to potentiate the effects of anti-tumor drugs and reverse the multi-drug resistance in cancer cells (Jiang et al., 2009).

Cell-cycle Arrest

Large quantities of emodin were isolated from the roots of Rheum emodi and a library of novel emodin derivatives 2–15 were prepared to evaluate their anti-proliferative activities against HepG2, MDA-MB-231 and NIH/3T3 cells lines. The derivatives 3 and 12 strongly inhibited the proliferation of HepG2 and MDA-MB-231 cancer cell line with an IC50 of 5.6, 13.03 and 10.44, 5.027, respectively, which is comparable to marketed drug epirubicin (III). The compounds 3 and 12 were also capable of inducing cell-cycle arrest and caspase dependent apoptosis in HepG2 cell lines and exhibit DNA intercalating activity. These emodin derivatives hold promise for developing safer alternatives to the marketed epirubicin (Narender et al., 2013).

Cell-cycle Arrest; MDR1 & AZT

3'-azido-3'-deoxythymidine (AZT) and emodin altered the cell-cycle distribution and led to an accumulation of cells in S phase. Meanwhile, the expression of MDR1 mRNA/p-gp protein was markedly decreased. These results show a synergistic growth-inhibitory effect of AZT and emodin in K562/ADM cells, which is achieved through S phase arrest. MDR1 might ultimately be responsible for these phenomena (Chen et al., 2013).

References

Chen P, Liu Y, Sun Y, et al. (2013). AZT and emodin exhibit synergistic growth-inhibitory effects on K562/ADM cells by inducing S phase cell-cycle arrest and suppressing MDR1 mRNA/p-gp protein expression. Pharm Biol.


Garg AK, Buchholz TA, Aggarwal BB. (2005). Chemo-sensitization and Radiosensitization of Tumors by Plant Polyphenols. Antioxid Redox Signal., 7(11-12):1630-47.


Jiang XF & Zhen YS. (1999). Reversal of Multi-drug resistance by emodin in cancer cells. Acta Pharmaceutica Sinica, 1999-03.


Jing X, Ueki N, Cheng J, Imanishi H, Hada T. (2002). Induction of apoptosis in hepatocellular carcinoma cell lines by emodin. Cancer Science, 93(8):874–882.


Kurebayashi J. (2001). Biological and clinical significance of HER2 overexpression in breast cancer. Breast Cancer, 8(1):45-51


Ma YS, Weng SW, Lin MW, et al. (2012). Anti-tumor effects of emodin on LS1034 human colon cancer cells in vitro and in vivo: Roles of apoptotic cell death and LS1034 tumor xenografts model. Food Chem Toxicol, 50(5): 1271–1278. doi: 10.1016/j.fct.2012.01.033.


Muto A, Hori M, Sasaki Y, et al. (2007). Emodin has a cytotoxic activity against human multiple myeloma as a Janus-activated kinase 2 inhibitor. Mol Cancer Ther. doi: 10.1158/1535-7163.MCT-06-0605.


Narender T, Sukanya P, Sharma K, et al. (2013). Preparation of novel anti-proliferative emodin derivatives and studies on their cell-cycle arrest, caspase dependent apoptosis and DNA binding interaction. Phytomedicine, 20(10):890-896.


Shrimali D, Shanmugam MK, Kumar AP, et al. (2013). Targeted abrogation of diverse signal transduction cascades by emodin for the treatment of inflammatory disorders and cancer. Cancer Lett:S0304-3835(13)00598-3. doi: 10.1016/j.canlet.2013.08.023.


Wei WT, Lin SZ, Liu DL, Wang ZH. (2013). The distinct mechanisms of the anti-tumor activity of emodin in different types of cancer (Review). Oncol Rep. doi: 10.3892/or.2013.2741.


Yu XW, Yang RZ. (2013). Effects of crude rhubarb on serum IL-15 and IL-18 levels in patients with severe acute pancreatitis. An Hui Yi Xue, 34(3): 285-287.

Luteolin

Cancer: Colorectal., ovarian, pancreatic

Action: Anti-inflammatory, immunomodulatory, radio-sensitizer, chemo-sensitizer

Luteolin is a flavonoid found in many plants and foods, including Terminalia chebula (Retz.), Prunella vulgaris (L.) and Perilla frutescens [(L.) Britton].

Luteolin is contained in Ocimum sanctum L . or Ocimum tenuiflorum L , commonly known as Holy Basil in English or Tulsi in various Indian languages, which is an important medicinal plant in the various traditional and folk systems of medicine in Southeast Asia. Scientific studies have shown it to possess anti-inflammatory, analgesic, anti-pyretic, anti-diabetic, hepato-protective, hypolipidemic, anti-stress, and immunomodulatory activities. It has been found to prevent chemical-induced skin, liver, oral., and lung cancers and mediates these effects by increasing the anti-oxidant activity, altering the gene expressions, inducing apoptosis, and inhibiting angiogenesis and metastasis.

Colon Cancer

Luteolin inhibited cyclin-dependent kinase (CDK)4 and CDK2 activity, resulting in G1 arrest with a concomitant decrease of phosphorylation of retinoblastoma protein. Activities of CDK4 and CDK2 decreased within 2 hours after luteolin treatment, with a 38% decrease in CDK2 activity (P < 0.05) observed in cells treated with 40 µmol/l luteolin. Luteolin also promoted G2/M arrest at 24 hours post-treatment by down-regulating cyclin B1 expression and inhibiting cell division cycle (CDC)2 activity. Luteolin promoted apoptosis with increased activation of caspases 3, 7, and 9 and enhanced poly(ADP-ribose) polymerase cleavage and decreased expression of p21CIP1/WAF1, survivin, Mcl-1, Bcl-xL, and Mdm-2. Lim et al. (2007) demonstrated that luteolin promotes both cell-cycle arrest and apoptosis in the HT-29 colon cancer cell line, providing insight about the mechanisms underlying its anti-tumorigenic activities.

Radio-protective

The aqueous extract of Perilla frutescens 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. The chemo-preventive and radio-protective properties of Perilla emphasize aspects that warrant future research to establish its activity and utility in cancer prevention and treatment (Baliga et al., 2013).

Anti-inflammatory

Pre-treatment of RAW 264.7 macrophages with luteolin, luteolin-7-glucoside, quercetin, and the isoflavonoid genistein inhibited both the LPS-stimulated TNF-α and interleukin-6 release, whereas eriodictyol and hesperetin only inhibited TNF-α release. From the compounds tested, luteolin and quercetin were the most potent in inhibiting cytokine production with an IC50 of less than 1 and 5 µM for TNF-α release, respectively. Moreover, luteolin inhibited LPS-induced phosphorylation of Akt. Treatment of macrophages with LPS resulted in increased IκB-α phosphorylation and reduced the levels of IκB-α. Pre-treatment of cells with luteolin abolished the effects of LPS on IκB-α.

Xagorari et al. (2001) concluded that luteolin inhibits protein tyrosine phosphorylation, nuclear factor-κB-mediated gene expression and pro-inflammatory cytokine production in murine macrophages.

Anti-inflammatory; Neuroinflammation

Pre-treatment of primary murine microglia and BV-2 microglial cells with luteolin inhibited LPS-stimulated IL-6 production at both the mRNA and protein levels. Whereas luteolin had no effect on the LPS-induced increase in NF-κB DNA binding activity, it markedly reduced AP-1 transcription factor binding activity. Consistent with this finding, luteolin did not inhibit LPS-induced degradation of IκB-α but inhibited JNK phosphorylation.

Luteolin consumption reduced LPS-induced IL-6 in plasma 4 hours after injection. Furthermore, luteolin decreased the induction of IL-6 mRNA by LPS in the hippocampus but not in the cortex or cerebellum. Taken together, these data suggest luteolin inhibits LPS-induced IL-6 production in the brain by inhibiting the JNK signaling pathway and activation of AP-1 in microglia. Thus, luteolin may be useful for mitigating neuroinflammation (Jang et al., 2008).

Immunostimulatory and Anti-inflammatory

Luteolin (Lut) possesses significant anti-inflammatory activity in well-established models of acute and chronic inflammation, such as xylene-induced ear edema in mice (ED50= 107 mg/ kg), carrageenin-induced swellingof the ankle, acetic acid-induced pleurisy and croton oil-induced gaseous pouch granuloma in rats. Lut had a marked inhibitory effect on the inflammatory exudation, but did not affect the number of leucocytes. Its combined immunostimulatory and anti-inflammatory activity, and inhibitory effect upon immediate hypersensitive response, provide the pharmacologic bases for the beneficial effects of Lut in the treatment of chronic bronchitis (Chen et al., 1986).

Anti-inflammatory

Luteolin dose-dependently inhibited the expression and production of those inflammatory genes and mediators in macrophages stimulated with lipopolysaccharide (LPS). Semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) assay further confirmed the suppression of LPS-induced TNF- α, IL-6, iNOS and COX-2 gene expression by luteolin at a transcriptional level. Luteolin also reduced the DNA binding activity of nuclear factor-kappa B (NF-κB) in LPS-activated macrophages.

In addition, luteolin significantly inhibited the LPS-induced DNA binding activity of activating protein-1 (AP-1). It was also found that luteolin attenuated the LPS-mediated protein kinase B (Akt) and IKK phosphorylation, as well as reactive oxygen species (ROS) production. In sum, these data suggest that, by blocking NF-κB and AP-1 activation, luteolin acts to suppress the LPS-elicited inflammatory events in mouse alveolar macrophages, and this effect was mediated, at least in part, by inhibiting the generation of reactive oxygen species. These observations suggest a possible therapeutic application of this agent for treating inflammatory disorders in the lung (Chen et al., 2007).

Pancreatic Cancer; Chemo-enhancing

Simultaneous treatment or pre-treatment (0, 6, 24 and 42h) of flavonoids and chemotherapeutic drugs and various concentrations (0-50µM) were assessed using the MTS cell proliferation assay. Pre-treatment for 24 hours with 13µM of either Apigenin or Luteolin, followed by Gem for 36 h 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, 36 hours). Lut (15µM, 24 hours) 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 Lut effectively aid in the anti-proliferative activity of chemotherapeutic drugs (Johnson et al., 2013).

Ovarian Cancer

Recent studies further indicate that luteolin potently inhibits VEGF production and suppresses ovarian cancer cell metastasis in vitro. Lastly, oridonin and wogonin were suggested to suppress ovarian CSCs as is reflected by down-regulation of the surface marker EpCAM.

Unlike NSAIDS (non-steroid anti-inflammatory drugs), well-documented clinical data for phyto-active compounds are lacking. In order to evaluate objectively the potential benefit of these compounds in the treatment of ovarian cancer, strategically designed, large scale studies are warranted (Chen et al., 2012).

Chemo-sensitizer

The sensitization effect of luteolin on cisplatin-induced apoptosis is p53 dependent, as such effect is only found in p53 wild-type cancer cells but not in p53 mutant cancer cells. Moreover, knockdown of p53 by small interfering RNA made p53 wild-type cancer cells resistant to luteolin and cisplatin. The critical role of c-Jun NH(2)-terminal kinase (JNK) was identified in regulation of p53 protein stability: luteolin activates JNK, and JNK then stabilizes p53 via phosphorylation, leading to reduced ubiquitination and proteasomal degradation.

An in vivo nude mice xenograft model confirmed that luteolin enhanced the cancer therapeutic activity of cisplatin via p53 stabilization and accumulation. In summary, data from this study reveal a novel molecular mechanism involved in the anti-cancer effects of luteolin and support its potential clinical application as a chemo-sensitizer in cancer therapy (Shi et al., 2007).

Breast Cancer; Chemo-sensitzer

Luteolin is a flavonoid that has been identified in many plant tissues and exhibits chemo-preventive or chemo-sensitizing properties against human breast cancer. However, the oncogenic molecules in human breast cancer cells that are inhibited by luteolin treatment have not been identified.

Relatively high levels of cyclin E2 (CCNE2) protein expression were detected in tamoxifen-resistant (TAM-R) MCF-7 cells. These results showed that the level of CCNE2 protein expression was specifically inhibited in luteolin-treated (5µM) TAM-R cells, either in the presence or absence of 4-OH-TAM (100nM). Combined treatment with 4-OH-TAM and luteolin synergistically sensitized the TAM-R cells to 4-OH-TAM. The results of this study 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).

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.

Chen CY, Peng WH, Tsai KD and Hsu SL. (2007). Luteolin suppresses inflammation-associated gene expression by blocking NF- κ B and AP-1 activation pathway in mouse alveolar macrophages. Life Sciences, 81(23-24):1602-1614. doi:10.1016/j.lfs.2007.09.028

Chen MZ, Jin WZ, Dai LM, Xu SY. (1986). Effect of luteolin on inflammation and immune function. Chinese Journal of Pharmacology and Toxicology, 1986-01.

Chen SS, Michael A, Butler-Manuel SA. (2012). Advances in the treatment of ovarian cancer: a potential role of anti-inflammatory phytochemicals. Discov Med, 13(68):7-17.

Jang S, Kelley KW, Johnson RW. (2008). Luteolin reduces IL-6 production in microglia by inhibiting JNK phosphorylation and activation of AP-1. PNAS, 105(21):7534-7539

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, S0278-6915(13)00491-2. doi: 10.1016/j.fct.2013.07.036.

Lim DY, Jeong Y, Tyner Al., Park JHY. (2007). Induction of cell-cycle arrest and apoptosis in HT-29 human colon cancer cells by the dietary compound luteolin. Am J Physiol Gastrointest Liver Physiol, 292: G66-G75. doi:10.1152/ajpgi.00248.2006.

Shi R, Huang Q, Zhu X, et al. (2007). Luteolin sensitizes the anti-cancer effect of cisplatin via c-Jun NH2-terminal kinase-mediated p53 phosphorylation and stabilization. Molecular Cancer Therapeutics, 6(4):1338-1347. doi: 10.1158/1535-7163.MCT-06-0638.

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.

Xagorari A, Papapetropoulos A, Mauromatis A, et al. (2001). Luteolin inhibits an endotoxin-stimulated phosphorylation cascade and pro-inflammatory cytokine production in macrophages. JPET, 296(1):181-187.

Kaempferol

Cancer:
Pancreatic, osteosarcoma, metastasis, ovarian cancer

Action: Anti-oxidation, anti-inflammatory, cell-cycle arrest, blood sugar regulation, estrogen receptor modulator, metastasis

Kaempferol is a flavonol compound present in various plants and Chinese medicinal herbs, including Allium cepa (L.).

Blood Sugar Regulation

It has been found that kaempferol, a flavonol compound present in various Chinese medicinal herbs, has cyto-protective effects on cultured clonal beta-cells and pancreatic human islets. Kaempferol treatment dose-dependently promoted viability, inhibited cellular apoptosis, and reduced caspase-3 activity in beta-cells and human islets exposed to chronic high glucose, with 10 µM kaempferol exerting the maximum effect. In addition, kaempferol treatment improved the expression of anti-apoptotic proteins Akt and Bcl-2, that was significantly reduced in beta-cells and human islets chronically exposed to hyperglycemia.

Furthermore, exposure of beta-cells and human islets to kaempferol restored high glucose-attenuated intracellular cAMP and ATP production. Inhibition of protein kinase A or Akt activation ablated the anti-apoptotic effect of kaempferol. These cytoprotective effects of kaempferol were associated with improved insulin secretory function and synthesis in beta-cells and human islets.

These findings provide evidence that kaempferol may be a naturally occurring anti-diabetic compound through protecting pancreatic beta-cell survival and function in a hostile environment that would otherwise lead to type 2 diabetes (Zhang et al., 2011).

Ovarian Cancer

Recent studies indicate that apigenin, genistein, kaempferol, luteolin, and quercetin potently inhibit VEGF production and suppress ovarian cancer cell metastasis in vitro. Unlike NSAIDS (non-steroid anti-inflammatory drugs), well-documented clinical data for phyto-active compounds are lacking. In order to evaluate objectively the potential benefit of these compounds in the treatment of ovarian cancer, strategically designed, large scale studies are warranted (Chen et al., 2012).

Estrogen Receptor Modulator

Kaempferol is a dietary flavonoid that can function as a selective estrogen receptor modulator (SERM). Estrogen-related receptors alpha and gamma (ERR α and ERRγ) are orphan nuclear receptors that play important roles in mitochondrial biogenesis and cancer development. Wang, Gao, & Wang (2013) have shown that kaempferol can functionally antagonize the activities of ERRs based on both response element reporter systems and target gene analysis. Kaempferol modulation of mitochondrial function and suppression of cancer cell growth has been confirmed. These findings suggest that kaempferol may exert its anti-cancer activities through antagonizing ERRs activity.

Osteosarcoma; Metastasis

Kaempferol displayed inhibitory effects on the invasion and adhesion of U-2 osteosarcoma (OS) cells in a concentration-dependent manner and it also inhibited the migration of U-2 OS cells in a concentration-dependent manner. Kaempferol treatment reduced the enzymatic activities and protein levels of matrix metalloproteinase (MMP)-2, MMP-9 and urokinase plasminogen activator (uPA) and furthermore, kaempferol was able to reduce the protein phosphorylation of ERK, p38 and JNK. Results suggest a potential role for kaempferol in the therapy of tumor metastasis of OS (Chen et al., 2013).

Cell-cycle Arrest

Kaempferol decreased cell viability as determined by MTT assays and induced a G2/M phase cell-cycle arrest in a concentration-dependent manner. CDK1/cyclin B expression and the AMPK and AKT signaling pathways contributed to kaempferol-induced G2/M cell-cycle arrest and autophagic cell death in SK-HEP-1 human hepatic cancer cells (Huang et al., 2013).

References

Chen SS, Michael A, Butler-Manuel SA. (2012). Advances in the treatment of ovarian cancer: a potential role of anti-inflammatory phytochemicals. Discov Med, 13(68):7-17.


Chen HJ, Lin CM, Lee CY, et al. (2013). Kaempferol suppresses cell metastasis via inhibition of the ERK-p38-JNK and AP-1 signaling pathways in U-2 OS human osteosarcoma cells. Oncol Rep, 30(2):925-32. doi: 10.3892/or.2013.2490.


Huang WW, Tsai SC, Peng SF, et al. (2013). Kaempferol induces autophagy through AMPK and AKT signaling molecules and causes G2/M arrest via down-regulation of CDK1/cyclin B in SK-HEP-1 human hepatic cancer cells. Int J Oncol, 42(6):2069-77. doi: 10.3892/ijo.2013.1909.


Wang H, Gao M, Wang J. (2013). Kaempferol inhibits cancer cell growth by antagonizing estrogen-related receptor α and γ activities. Cell Biol Int. doi: 10.1002/cbin.10152.


Zhang Y, Liu D. (2011). Flavonol kaempferol improves chronic hyperglycemia-impaired pancreatic beta-cell viability and insulin secretory function. Eur J Pharmacol, 670(1):325-32. doi: 10.1016/j.ejphar.2011.08.011.

Evodiamine

Cancer: Pancreatic, gastric, breast; ER+, ER-, lung

Action: Inhibits NF- κB, inhibits metastasis, increases intracellular ROS, apoptosis, cell-cycle arrest, anti-cancer, MDR

Evodiamine, a naturally occurring indole alkaloid, is one of the main bioactive ingredients of Evodia rutaecarpa [(Juss.) Benth.] (alkaloidal component of the extract). With respect to the pharmacological actions of evodiamine, more attention has been paid to beneficial effects in insults involving cancer, obesity, nociception, inflammation, cardiovascular diseases, Alzheimer's disease, infectious diseases and thermo-regulative effects. Evodiamine has evolved a superior ability to bind various proteins (Yu et al., 2013). Evodiamine exhibits anti-proliferative, anti-metastatic, and apoptotic activities.

Anti-cancer, MDR

Evodiamine possesses anti-anxiety, anti-obesity, anti-nociceptive, anti-inflammatory, anti-allergic, and anti-cancer effects. As well, it has thermoregulation, protection of myocardial ischemia-reperfusion injury and vessel-relaxing activities (Kobayashi, 2003; Shin et al., 2007; Ko et al., 2007; Ji, 2011). Evodiamine exhibits anti-cancer activities both in vitro and in vivo by inducing cell-cycle arrest or apoptosis, and inhibiting angiogenesis, invasion, and metastasis in a variety of cancer cell lines (Ogasawara et al., 2001; Ogasawara et al., 2002; Fei et al., 2003; Shyu et al., 2006). It presents anti-cancer potentials at micromolar concentrations and even at the nanomolar level in some cell lines in vitro (Lee et al., 2006; Wang, Li, & Wang, 2010). Evodiamine also stimulates autophagy, which serves as a survival function (Yang et al., 2008). Compared with other compounds, evodiamine is less toxic to normal human cells, such as human peripheral blood mononuclear cells (Fei et al., 2003; Zhang et al., 2004). It also inhibits the proliferation of adriamycin-resistant human breast cancer NCI/ADR-RES cells both in vitro and in Balb-c/nude mice (Liao et al., 2005).

Lung Cancer, Cell-cycle Arrest

Evodiamine (10  mg/kg) administrated orally twice daily significantly inhibits   tumor growth (Liao et al., 2005). Moreover, treatment with 10 mg/kg evodiamine from the 6th day after tumor inoculation into mice reduces lung metastasis and does not affect the body weight of mice during the experimental period (Ogasawara et al., 2001).

Cell-cycle Arrest

Evodiamine inhibits TopI enzyme, forms the DNA covalent complex with a similar concentration to that of irinotecan, and induces DNA damage (Chan et al., 2009; Tsai et al., 2010; Dong et al., 2010). However, TopI may not be the main target of this compound. Cancer cells treated with evodiamine exhibit G 2 / M phase arrest (Kan et al., 2004; Huang et al., 2004; Liao et al., 2005) rather than S phase arrest, which is not consistent with the mechanism of classic TopI inhibitors, such as irinotecan. Therefore, other targets aside from TopI may also be important for realizing the anti-cancer potentials of evodiamine. This statement is supported by the fact that evodiamine has effects on tubulin polymerization (Huang et al., 2004).

Increases Intracellular ROS, Apoptosis

Exposure to evodiamine rapidly increases intracellular ROS followed by an onset of mitochondrial depolarization (Yang et al., 2007). The generation of ROS and nitric oxide acts in synergy and triggers mitochondria-dependent apoptosis (Yang et al., 2008). Evodiamine also induces caspase-dependent and caspase-independent apoptosis, down-regulates Bcl-2 expression, and up-regulates Bax expression in some cancer cells (Zhang et al., 2003; Lee et al., 2006). The phosphatidylinositol 3-kinase/Akt/caspase and Fas ligand (Fas-L)/NF-κB signaling pathways might account for evodiamine-induced cell death. Moreover, these signals could be increased by the ubiquitin-proteasome pathway (Wang, Li, & Wang, 2010).

Inhibits Metastasis

Evodiamine has a marked inhibitory activity on tumor cell migration in vitro. When evodiamine at 10 mg/kg was administered into mice from the 6th day after tumor inoculation, the number of tumor nodules in lungs was decreased by 48% as compared to control. The inhibition rate was equivalent to that produced by cisplatin. Results suggest that evodiamine may be regarded as a promising agent in tumor metastasis therapy (Ogasawara et al., 2005).

Inhibits NF-κB

Evodiamine inhibited tumor necrosis factor (TNF)-induced Akt activation and its association with IKK. This down-regulation potentiated the apoptosis induced by cytokines and chemotherapeutic agents and suppressed TNF-induced invasive activity. Overall, these results indicate that evodiamine inhibits both constitutive and induced NF-κB activation and NF-κB-regulated gene expression (Takada et al., 2005).

Breast Cancer

Endocrine sensitivity, assessed by the expression of estrogen receptor (ER), has long been the predict factor to guide therapeutic decisions. Tamoxifen has been the most successful hormonal treatment in endocrine-sensitive breast cancer. However, in estrogen-insensitive cancer tamoxifen showed less effectiveness than in estrogen-sensitive cancer. It is interesting to develop new drugs against both hormone-sensitive and insensitive tumor. In this present study Wang et al. (2013) examined anti-cancer effects of evodiamine extracted from the Chinese herb, Evodiae fructus, in estrogen-dependent and -independent human breast cancer cells, MCF-7 and MDA-MB-231 cells, respectively.

Breast Cancer; ER+, ER-

The expression of ER α and β in protein and mRNA levels was down-regulated by evodiamine according to data from immunoblotting and RT-PCR analysis. Overall, results indicate that evodiamine mediates degradation of ER and induces caspase-dependent pathway leading to inhibition of proliferation of breast cancer cell lines. It suggests that evodiamine may in part mediate through ER-inhibitory pathway to inhibit breast cancer cell proliferation.

Evodiamine (10 mg/kg) significantly reduced tumor growth and pulmonary metastasis. In vitro, evodiamine inhibited cell migration and invasion abilities through down-regulation of MMP-9, urokinase-type plasminogen activator (uPA) and uPAR expression. Evodiamine-induced G0/G1 arrest and apoptosis were associated with a decrease in Bcl-2, cyclin D1 and cyclin-dependent kinase 6 (CDK6) expression and an increase in Bax and p27Kip1 expression (Du et al., 201).

Gastric Cancer

A study by Rasul et al. (2012) was conducted to investigate the synchronized role of autophagy and apoptosis in evodiamine-induced cytotoxic activity on SGC-7901 human gastric adenocarcinoma cells and further to elucidate the underlying molecular mechanisms. Evodiamine significantly inhibited the proliferation of SGC-7901 cells and induced G2/M phase cell-cycle arrest.

Evodiamine-induced autophagy is partially involved in the death of SGC-7901 cells which was confirmed by using the autophagy inhibitor 3-methyladenine (3-MA). Evodiamine has therapeutic potential against cancers.

Pancreatic Cancer

In vitro application of the combination therapy triggered significantly higher frequency of pancreatic cancer cells apoptosis, inhibited the activities of PI3K, Akt, PKA, mTOR and PTEN, and decreased the activation of NF-κB and expression of NF- κB-regulated products. Evodiamine can augment the therapeutic effect of gemcitabine in pancreatic cancer through direct or indirect negative regulation of the PI3K/Akt pathway (Wei et al., 2012).

References

Chan ALF, Chang WS, Chen LM et al. (2009). Evodiamine stabilizes topoisomerase I-DNA cleavable complex to inhibit topoisomerase I activity. Molecules, (14):4:1342–1352.


Dong G, Sheng C, Wang CS, et al. (2010). Selection of evodiamine as a novel topoisomerase i inhibitor by structure-based virtual screening and hit optimization of evodiamine derivatives as anti-tumor agents. Journal of Medicinal Chemistry, 53(21):7521–7531.


Du J, Wang XF, Zhou QM, et al. (2013). Evodiamine induces apoptosis and inhibits metastasis in MDA “American Typewriter”; “American Typewriter”;‑ MB-231 human breast cancer cells in vitro and in vivo. Oncol Rep, 30(2):685-94. doi: 10.3892/or.2013.2498.


Fei XF, Wang BX, T. Li TJ et al. (2003). Evodiamine, a constituent of Evodiae Fructus, induces anti-proliferating effects in tumor cells. Cancer Science, 94(1):92–98.


Huang YC, Guh JH, Teng CM. (2004). Induction of mitotic arrest and apoptosis by evodiamine in human leukemic T-lymphocytes. Life Sciences, 75(1):35–49.


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


Kan SF, Huang WJ, Lin LC, Wang PS. (2004). Inhibitory effects of evodiamine on the growth of human prostate cancer cell line LNCaP. International Journal of Cancer, 110(5):641–651.


Ko HC, Wang YH, Liou KT et al. (2007). Anti-inflammatory effects and mechanisms of the ethanol extract of Evodia rutaecarpa and its bioactive components on neutrophils and microglial cells. European Journal of Pharmacology, 555(2-3):211–217.


Kobayashi Y. (2003). The nociceptive and anti-nociceptive effects of evodiamine from fruits of Evodia rutaecarpa in mice. Planta Medica, 69(5):425–428.


Lee TJ, Kim EJ, Kim S et al. (2006). Caspase-dependent and caspase-independent apoptosis induced by evodiamine in human leukemic U937 cells. Molecular Cancer Therapeutics, 5(9):2398–2407.


Liao CH, Pan SL, Guh JH et al. (2005). Anti-tumor mechanism of evodiamine, a constituent from Chinese herb Evodiae fructus, in human multiple-drug resistant breast cancer NCI/ADR-RES cells in vitro and in vivo. Carcinogenesis, 26(5):968–975.


Ogasawara M, Matsubara T, Suzuki H. (2001). Inhibitory effects of evodiamine on in vitro invasion and experimental lung metastasis of murine colon cancer cells. Biological and Pharmaceutical Bulletin, 24(8):917–920.


Ogasawara M, Matsunaga T, Takahashi S, Saiki I, Suzuki H. (2002). Anti-invasive and metastatic activities of evodiamine. Biological and Pharmaceutical Bulletin, 25(11):1491–1493.


Rasul A, Yu B, Zhong L, et al. (2012). Cytotoxic effect of evodiamine in SGC-7901 human gastric adenocarcinoma cells via simultaneous induction of apoptosis and autophagy. Oncol Rep, 27(5):1481-7. doi: 10.3892/or.2012.1694


Shin YW, Bae EA, Cai XF, Lee JJ, and Kim DH. (2007). In vitro and in vivo antiallergic effect of the fructus of Evodia rutaecarpa and its constituents, Biological and Pharmaceutical Bulletin, 30(1):197–199, 2007.


Shyu KG, Lin S, Lee CC et al. (2006). Evodiamine inhibits in vitro angiogenesis: implication for anti-tumorgenicity. Life Sciences, 78(19):2234–2243.


Takada Y, Kobayashi Y, Aggarwal BB. (2005). Evodiamine Abolishes Constitutive and Inducible NF- κB Activation by Inhibiting IκBα Kinase Activation, Thereby Suppressing NF-κ B-regulated Antiapoptotic and Metastatic Gene Expression, Up-regulating Apoptosis, and Inhibiting Invasion. The Journal of Biological Chemistry, 280:17203-17212. doi: 10.1074/jbc.M500077200.


Tsai HP, Lin LW, Lai ZY et al. (2010). Immobilizing topoisomerase I on a surface plasmon resonance biosensor chip to screen for inhibitors. Journal of Biomedical Science, 17(1):49.


Wang C, Li S, Wang MW. (2010). Evodiamine-induced human melanoma A375-S2 cell death was mediated by PI3K/Akt/caspase and Fas-L/NF- κ B signaling pathways and augmented by ubiquitin-proteasome inhibition. Toxicology in Vitro, 24(3):898–904.


Wang KL, Hsia SM, Yeh JY, et al. (2013). Anti-Proliferative Effects of Evodiamine on Human Breast Cancer Cells. PLoS One, 8(6):e67297.


Wei WT, Chen H, Wang ZH, et al. (2012). Enhanced anti-tumor efficacy of gemcitabine by evodiamine on pancreatic cancer via regulating PI3K/Akt pathway. Int J Biol Sci, 8(1):1-14.


Yu H, Jin H, Gong W, Wang Z, Liang H. (2013). Pharmacological actions of multi-target-directed evodiamine. Molecules, 18(2):1826-43. doi: 10.3390/molecules18021826.


Yang J, Wu LJ, Tashino SI, et al. (2007). Critical roles of reactive oxygen species in mitochondrial permeability transition in mediating evodiamine-induced human melanoma A375-S2 cell apoptosis. Free Radical Research, 41(10):1099–1108.


Zhang Y, Wu LJ, Tashiro SI, Onodera S, Ikejima T. (2003). Intracellular regulation of evodiamine-induced A375-S2 cell death. Biological and Pharmaceutical Bulletin, 26(11):1543–1547.


Zhang Y, Zhang QH, Wu LJ, et al. (2004). Atypical apoptosis in L929 cells induced by evodiamine isolated from Evodia rutaecarpa. Journal of Asian Natural Products Research, 6(1):19–27.

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.

Andrographolide

Cancer: Leukemia, colorectal, lung

Action: Immunomodulatory,anti-inflammatory,anti-metastatic

Andrographolide (Andro), a diterpenoid lactone isolated from a traditional herbal medicine Andrographis paniculata [(Burm. f.) Wall. Ex Nees], is known to possess multiple pharmacological activities. Andrographolide has been shown to exhibit antioxidative, anti-cancer, anti-inflammatory, anti-diabetes, and anti-aging properties (Trivedi et al., 2007; Chao et al., 2010).

Immunomodulatory Activity

The immunomodulatory activity of HN-02, an extract containing a mixture of andrographolides, was evaluated at 1.0, 1.5, and 2.5 mg/kg on different in vivo and in vitro experimental models. It was also found that HN-02 treatment stimulated phagocytosis in mice. A significant increase in total WBC count and relative weight of spleen and thymus was observed in mice during 30 days of treatment with HN-02.

The present experimental findings demonstrate that HN-02 has the ability to enhance immune function, possibly through modulation of immune responses altered during antigen interaction, and to reverse the immunosuppression induced by CYP (Naik, 2009).

The ethanol extract and purified diterpene andrographolides of Andrographis paniculata (Acanthaceae) induced significant stimulation of antibody and delayed type hypersensitivity (DTH) response to sheep red blood cells (SRBC) in mice. The plant preparations also stimulated non-specific immune response of the animals measured in terms of macrophage migration index (MMI) phagocytosis of Escherichia coli and proliferation of splenic lymphocytes. The stimulation of both antigen specific and non-specific immune response was, however, of lower order with andrographolide than with the ethanol extract, suggesting that substance(s) other than andrographolide present in the extract may also be contributing towards immunostimulation (Puri, 1993)

Anti-inflammatory and Leukemic Therapies

Andrographolide has been shown to attenuate MMP-9 expression, with its main mechanism likely involving the NF-κB signal pathway. These results provide new opportunities for the development of new anti-inflammatory and leukemic therapies. This activity was shown in a study in which andrographolide (1–50µM) exhibited concentration-dependent inhibition of MMP-9 activation, induced by either tumor necrosis factor-α (TNF-α), or lipopolysaccharide (LPS), in THP-1cells.

Anti-inflammatory

Lee et al (2012) found that andrographolide could significantly inhibit the degradation of inhibitor-κB-α (IκB-α) induced by TNF-α. They used electrophoretic mobility shift assay and reporter gene detection to show that andrographolide also markedly inhibited NF-signaling, anti-translocation and anti-activation. These results provide new opportunities for the development of new anti-inflammatory and leukemic therapies.

Lung Cancer Metastasis

Andrographolide is known to have the potential to be developed as a chemotherapeutic agent, in particular in the treatment of lung cancer. In order to understand the anti-cancer properties of andrographolide, its effect on migration and invasion in human lung cancer A549 cells was examined. The results of the wound-healing assay and the in vitro transwell assay revealed that andrographolide inhibited dose-dependently the migration and invasion of A549 cells under non-cytotoxic concentrations.

These results indicated that andrographolide exerted an inhibitory effect on the activity and the mRNA and protein levels of MMP-7, but not MMP-2 or MMP-9. The andrographolide-inhibited MMP-7 expression or activity appeared to occur via activator protein-1 (AP-1) because its DNA binding activity was suppressed by andrographolide. Additionally, the transfection of Akt over-expression vector (Akt1 cDNA) to A549 cells could result in an increase expression of MMP-7 concomitantly with a marked induction on cell invasion. These findings suggested that the inhibition on MMP-7 expression by andrographolide may be through suppression on PI3K/Akt/AP-1 signaling pathway, which in turn leads to the reduced invasiveness of the cancer cells (Lee, 2010).

Colorectal Cancer

Andrographolide has also been shown to have potent anti-cancer activity against human colorectal carcinoma Lovo cells by inhibiting cell-cycle progression. To further investigate the mechanism for the anti-cancer properties of andrographolide, it was used to examine the effect on migration and invasion of Lovo cells. The results of wound-healing assay and in vitro transwell assay revealed that andrographolide inhibited dose-dependently the migration and invasion of Lovo cells under non-cytotoxic concentrations.

The down-regulation of MMP-7 appeared to be via the inactivation of activator protein-1 (AP-1) since the treatment with andrographolide suppressed the nuclear protein level of AP-1, which was accompanied by a decrease in DNA-binding level of the factor. Taken together, these results indicate that andrographolide reduces the MMP-7-mediated cellular events in Lovo cells, and provide a new mechanism for its anti-cancer activity (Shi, 2009)

Anti-inflammatory, Induces Apoptosis

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an important member of the tumor necrosis factor subfamily with great potential in cancer therapy; additionally andrographolide is known to possess potent anti-inflammatory and anti-cancer activities which may be attributed to its action on TRAIL. It has been shown that pre-treatment with andrographolide significantly enhances TRAIL-induced apoptosis in various human cancer cell lines, including those TRAIL-resistant cells.

Pre-treatment with an anti-oxidant (N-acetylcysteine) or a c-Jun NH(2)-terminal kinase inhibitor (SP600125) effectively prevented andrographolide-induced p53 activation and DR4 up-regulation and eventually blocked the andrographolide-induced sensitization on TRAIL-induced apoptosis. Taken together, these results present a novel anti-cancer effect of andrographolide and support its potential application in cancer therapy to overcome TRAIL resistance (Zhou, 2008).

References

Chao HP, Kuo CD, Chiu JH, Fu SL. (2010). Andrographolide exhibits anti-invasive activity against colon cancer cells via inhibition of MMP2 activity. Planta Medica, 76(16):1827–1833. doi: 10.1055/s-0030-1250039.


Lee WR, Chung CL, Hsiao CJ, et al. (2012). Suppression of matrix metalloproteinase-9 expression by andrographolide in human monocytic THP-1 cells via inhibition of NF- κB activation. Phytomedicine, 19(3):270-277. doi: 10.1016/j.phymed.2011.11.012


Lee YC, Lin HH, Hsu CH, et al. (2010). Inhibitory effects of andrographolide on migration and invasion in human non-small-cell lung cancer A549 cells via down-regulation of PI3K/Akt signaling pathway. Eur J Pharmacol, 632(1-3):23-32. doi: 10.1016/j.ejphar.2010.01.009.


Naik SR, Hule A. (2009). Evaluation of Immunomodulatory Activity of an Extract of Andrographolides from Andographis paniculata. Planta Med, 75(8):785-91. doi: 10.1055/s-0029-1185398.


Puri A, Saxena R, Saxena RP, et al. (1993). Immunostimulant agents from Andrographis paniculata. J Nat Prod, 56(7):995-9.


Shi MD, Lin HH, Chiang TA, et al. (2009). Andrographolide could inhibit human colorectal carcinoma Lovo cells migration and invasion via down-regulation of MMP-7 expression. Chem Biol Interact, 180(3):344-52. doi: 10.1016/j.cbi.2009.04.011.


Trivedi NP, Rawal UM, Patel BP. (2007). Hepato-protective effect of andrographolide against hexachlorocyclohexane- induced oxidative injury. Integrative Cancer Therapies, 6(3):271–280. doi: 10.1177/1534735407305985.


Zhou J, Lu GD, Ong CS, Ong CN, Shen HM. (2008). Andrographolide sensitizes cancer cells to TRAIL-induced apoptosis via p53-mediated death receptor 4 up-regulation. Mol Cancer Ther, 7(7):2170-80. doi: 10.1158/1535-7163.MCT-08-0071.