Category Archives: A549

Wogonin

Cancer:
Breast, lung (NSCLC), gallbladder carcinoma, osteosarcoma, colon, cervical

Action: Neuro-protective, anti-lymphangiogenesis, anti-angiogenic, anti-estrogenic, chemo-sensitizer, pro-oxidative, hypoxia-induced drug resistance, anti-metastatic, anti-tumor, anti-inflammatory

Wogonin is a plant monoflavonoid isolated from Scutellaria rivularis (Benth.) and Scutellaria baicalensis (Georgi).

Breast Cancer; ER+ & ER-

Effects of wogonin were examined in estrogen receptor (ER)-positive and -negative human breast cancer cells in culture for proliferation, cell-cycle progression, and apoptosis. Cell growth was attenuated by wogonin (50-200 microM), independently of its ER status, in a time- and concentration-dependent manner. Apoptosis was enhanced and accompanied by up-regulation of PARP and Caspase 3 cleavages as well as pro-apoptotic Bax protein. Akt activity was suppressed and reduced phosphorylation of its substrates, GSK-3beta and p27, was observed. Suppression of Cyclin D1 expression suggested the down-regulation of the Akt-mediated canonical Wnt signaling pathway.

ER expression was down-regulated in ER-positive cells, while c-ErbB2 expression and its activity were suppressed in ER-negative SK-BR-3 cells. Wogonin feeding to mice showed inhibition of tumor growth of T47D and MDA-MB-231 xenografts by up to 88% without any toxicity after 4 weeks of treatment. As wogonin was effective both in vitro and in vivo, our novel findings open the possibility of wogonin as an effective therapeutic and/or chemo-preventive agent against both ER-positive and -negative breast cancers, particularly against the more aggressive and hormonal therapy-resistant ER-negative types (Chung et al., 2008).

Neurotransmitter Action

Kim et al. (2011) found that baicalein and wogonin activated the TREK-2 current by increasing the opening frequency (channel activity: from 0.05 ± 0.01 to 0.17 ± 0.06 in baicalein treatment and from 0.03 ± 0.01 to 0.29 ± 0.09 in wogonin treatment), while leaving the single-channel conductance and mean open time unchanged. Baicalein continuously activated TREK-2, whereas wogonin transiently activated TREK-2. Application of baicalein and wogonin activated TREK-2 in both cell attached and excised patches, suggesting that baicalein and wogonin may modulate TREK-2 either directly or indirectly with different mechanisms. These results suggest that baicalein- and wogonin-induced TREK-2 activation help set the resting membrane potential of cells exposed to pathological conditions and thus may give beneficial effects in neuroprotection.

Anti-metastasic

The migration and invasion assay was used to evaluate the anti-metastasis effect of wogonin. Wogonin at the dose of 1–10 µM, which did not induce apoptosis, significantly inhibited the mobility and invasion activity of human gallbladder carcinoma GBC-SD cells. In addition, the expressions of matrix metalloproteinase (MMP)-2, MMP-9 and phosphorylated extracellular regulated protein kinase 1/2 (ERK1/2) but not phosphorylated Akt were dramatically suppressed by wogonin in a concentration-dependent manner. Furthermore, the metastasis suppressor maspin was confirmed as the downstream target of wogonin.

These findings suggest that wogonin inhibits cell mobility and invasion by up-regulating the metastasis suppressor maspin. Together, these data provide novel insights into the chemo-protective effect of wogonin, a main active ingredient of Chinese medicine Scutellaria baicalensis (Dong et al., 2011).

Anti-tumor and Anti-metastatic

Kimura & Sumiyoshi (2012) examined the effects of wogonin isolated from Scutellaria baicalensis roots on tumor growth and metastasis using a highly metastatic model in osteosarcoma LM8-bearing mice. Wogonin (25 and 50mg/kg, twice daily) reduced tumor growth and metastasis to the lung, liver and kidney, angiogenesis (CD31-positive cells), lymphangiogenesis (LYVE-1-positive cells), and TAM (F4/80-positive cell) numbers in the tumors of LM8-bearing mice. Wogonin (10–100µM) also inhibited increases in IL-1β production and cyclooxygenase (COX)-2 expression induced by lipopolysaccharide in THP-1 macrophages. The anti-tumor and anti-metastatic actions of wogonin may be associated with the inhibition of VEGF-C-induced lymphangiogenesis through a reduction in VEGF-C-induced VEGFR-3 phosphorylation by the inhibition of COX-2 expression and IL-1β production in Tumor-associated macrophages (TAMs).

Anti-inflammatory

Wogonin extracted from Scutellariae baicalensis and S. barbata is a cell-permeable and orally available flavonoid that displays anti-inflammatory properties. Wogonin is reported to suppress the release of NO by iNOS, PGE2 by COX-2, pro-inflammatory cytokines, and MCP-1 gene expression and NF-kB activation (Chen et al., 2008).

Hypoxia-Induced Drug Resistance (MDR)

Hypoxia-induced drug resistance is a major obstacle in the development of effective cancer therapy. The reversal abilities of wogonin on   hypoxia resistance were examined and the underlying mechanisms discovered. MTT assay revealed that hypoxia increased maximal 1.71-, 2.08-, and 2.15-fold of IC50 toward paclitaxel, ADM, and DDP in human colon cancer cell lines HCT116, respectively. Furthermore, wogonin showed strong reversal potency in HCT116 cells in hypoxia and the RF reached 2.05. Hypoxia-inducible factor-1α (HIF-1α) can activate the expression of target genes involved in glycolysis. Wogonin decreased the expression of glycolysis-related proteins (HKII, PDHK1, LDHA), glucose uptake, and lactate generation in a dose-dependent manner.

In summary, wogonin could be a good candidate for the development of a new multi-drug resistance (MDR) reversal agent and its reversal mechanism probably is due to the suppression of HIF-1α expression via inhibiting PI3K/Akt signaling pathway (Wang et al., 2013).

NSCLC

Wogonin, a flavonoid originated from Scutellaria baicalensis Georgi, has been shown to enhance TRAIL-induced apoptosis in malignant cells in in vitro studies. In this study, the effect of a combination of TRAIL and wogonin was tested in a non-small-cell lung cancer xenografted tumor model in nude mice. Consistent with the in vitro study showing that wogonin sensitized A549 cells to TRAIL-induced apoptosis, wogonin greatly enhanced TRAIL-induced suppression of tumor growth, accompanied with increased apoptosis in tumor tissues as determined by TUNEL assay.

The down-regulation of these antiapoptotic proteins was likely mediated by proteasomal degradation that involved intracellular reactive oxygen species (ROS), because wogonin robustly induced ROS accumulation and ROS scavengers butylated hydroxyanisole (BHA) and N-acetyl-L-cysteine (NAC) and the proteasome inhibitor MG132 restored the expression of these antiapoptotic proteins in cells co-treated with wogonin and TRAIL.

These results show for the first time that wogonin enhances TRAIL's anti-tumor activity in vivo, suggesting this strategy has an application potential for clinical anti-cancer therapy (Yang et al., 2013).

Colon Cancer

Following treatment with baicalein or wogonin, several apoptotic events were observed, including DNA fragmentation, chromatin condensation and increased cell-cycle arrest in the G1 phase. Baicalein and wogonin decreased Bcl-2 expression, whereas the expression of Bax was increased in a dose-dependent manner compared with the control. Furthermore, the induction of apoptosis was accompanied by an inactivation of phosphatidylinositol 3-kinase (PI3K)/Akt in a dose-dependent manner.

The administration of baicalein to mice resulted in the inhibition of the growth of HT-29 xenografts without any toxicity following 5 weeks of treatment. The results indicated that baicalein induced apoptosis via Akt activation in a p53-dependent manner in the HT-29 colon cancer cells and that it may serve as a chemo-preventive or therapeutic agent for HT-29 colon cancer (Kim et al., 2012).

Breast

The involvement of insulin-like growth factor-1 (IGF-1) and estrogen receptor α (ERα) in the inhibitory effect of wogonin on the breast adenocarcinoma growth was determined. Moreover, the effect of wogonin on the angiogenesis of chick chorioallantoic membrane (CAM) was also investigated. The results showed wogonin and ICI182780 both exhibited a potent ability to blunt IGF-1-stimulated MCF-7 cell growth. Either of wogonin and ICI182780 significantly inhibited ERα and p-Akt expressions in IGF-1-treated cells. The inhibitory effect of wogonin showed no difference from that of ICI182780 on IGF-1-stimulated expressions of ERα and p-Akt. Meanwhile, wogonin at different concentrations showed significant inhibitory effect on CAM angiogenesis.

These results suggest the inhibitory effect of wogonin on breast adenocarcinoma growth via inhibiting IGF-1-mediated PI3K-Akt pathway and regulating ERα expression. Furthermore, wogonin has a strong anti-angiogenic effect on CAM model (Ma et al., 2012).

Chemoresistance; Cervical Cancer, NSCLC

Chemoresistance to cisplatin is a major limitation of cisplatin-based chemotherapy in the clinic. The combination of cisplatin with other agents has been recognized as a promising strategy to overcome cisplatin resistance. Previous studies have shown that wogonin (5,7-dihydroxy-8-methoxyflavone), a flavonoid isolated from the root of the medicinal herb Scutellaria baicalensis Georgi, sensitizes cancer cells to chemotheraputics such as etoposide, adriamycin, tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and TNF.

In this study, the non-small-cell lung cancer cell line A549 and the cervical cancer cell line HeLa were treated with wogonin or cisplatin individually or in combination. It was found for the first time that wogonin is able to sensitize cisplatin-induced apoptosis in both A549 cells and HeLa cells as indicated by the potentiation of activation of caspase-3, and cleavage of the caspase-3 substrate PARP in wogonin and cisplatin co-treated cells.

Results provided important new evidence supporting the potential use of wogonin as a cisplatin sensitizer for cancer therapy (He et al., 2012).

References

Chen LG, Hung LY, Tsai KW, et al. (2008). Wogonin, a bioactive flavonoid in herbal tea, inhibits inflammatory cyclooxygenase-2 gene expression in human lung epithelial cancer cells. Mol Nutr Food Res. 52:1349-1357.


Chung H, Jung YM, Shin DH, et al. (2008). Anti-cancer effects of wogonin in both estrogen receptor-positive and -negative human breast cancer cell lines in vitro and in nude mice xenografts. Int J Cancer, 122(4):816-22.


Dong P, Zhang Y, Gu J, et al. (2011). Wogonin, an active ingredient of Chinese herb medicine Scutellaria baicalensis, inhibits the mobility and invasion of human gallbladder carcinoma GBC-SD cells by inducing the expression of maspin. J Ethnopharmacol, 137(3):1373-80. doi: 10.1016/j.jep.2011.08.005.


He F, Wang Q, Zheng XL, et al. (2012). Wogonin potentiates cisplatin-induced cancer cell apoptosis through accumulation of intracellular reactive oxygen species. Oncology Reports, 28(2), 601-605. doi: 10.3892/or.2012.1841.


Kim EJ, Kang D, Han J. (2011). Baicalein and wogonin are activators of rat TREK-2 two-pore domain K+ channel. Acta Physiologica, 202(2):185–192. doi: 10.1111/j.1748-1716.2011.02263.x.


Kim SJ, Kim HJ, Kim HR, et al. (2012). Anti-tumor actions of baicalein and wogonin in HT-29 human colorectal cancer cells. Mol Med Rep, 6(6):1443-9. doi: 10.3892/mmr.2012.1085.


Kimura Y & Sumiyoshi M. (2012). Anti-tumor and anti-metastatic actions of wogonin isolated from Scutellaria baicalensis roots through anti-lymphangiogenesis. Phytomedicine, 20(3-4):328-336. doi:10.1016/j.phymed.2012.10.016


Ma X, Xie KP, Shang F, et al. (2012). Wogonin inhibits IGF-1-stimulated cell growth and estrogen receptor α expression in breast adenocarcinoma cell and angiogenesis of chick chorioallantoic membrane. Sheng Li Xue Bao, 64(2):207-12.


Wang H, Zhao L, Zhu LT, et al. (2013). Wogonin reverses hypoxia resistance of human colon cancer HCT116 cells via down-regulation of HIF-1α and glycolysis, by inhibiting PI3K/Akt signaling pathway. Mol Carcinog. doi: 10.1002/mc.22052.


Yang L, Wang Q, Li D, et al. (2013). Wogonin enhances anti-tumor activity of tumor necrosis factor-related apoptosis-inducing ligand in vivo through ROS-mediated down-regulation of cFLIPL and IAP proteins. Apoptosis, 18(5):618-26. doi: 10.1007/s10495-013-0808-8.

Waltonitone

Cancer: Hepatocellular carcinoma, lung

Action: Induces cell-cycle arrest

Hepatocellular Carcinoma

Waltonitone, a new ursane-type pentacyclic triterpene isolated from Gentian waltonii Burkill, significantly inhibited human hepatocellular carcinoma BEL-7402 cells growth. Apoptosis induced by waltonitone was characterized by AO/EB staining and flow cytometric analysis. Apoptosis microarray assay results showed BCL-2 family genes might especially play an important role in waltonitone-induced apoptosis.

These studies demonstrated that waltonitone might inhibit hepatocellular carcinoma cell growth and induce apoptosis in vitro and in vivo (Zhang et al., 2009a).

Adenocarcinomic Lung Cancer

Natural compounds are a great source of cancer chemotherapeutic agents. An investigation by Zhang et al. (2012) indicates that waltonitone (WT), a triterpene extracted from medicinal plants, inhibits the proliferation of A549 cells in a concentration- and time-dependent manner.

Furthermore, the treatment of A549 cells with waltonitone altered the expression of miRNAs. It was found that 27 miRNAs were differentially expressed in waltonitone-treated cells, of which 8 miRNAs target genes related to cell proliferation and apoptosis.

In summary, results demonstrate that waltonitone has a significant inhibitory effect on the proliferation of A549 cells. It is possible that up-regulation of Bax/Bcl-2 and regulation of expression of specific miRNAs play a role in inhibition of proliferation and induction of apoptosis in waltonitone-treated cells. Waltonitone can be applied to lung carcinoma as a chemotherapeutic candidate.

Hepatocellular Carcinoma

WT could inhibit the BEL-7402 cells growth, induce the S-phase cell-cycle arrest, and activate Akt and ERK1/2 phosporylation. Moreover, the cell growth inhibition and S-phase cell-cycle arrest induction of WT on BEL-7402 cells could be blocked by Akt and ERK1/2 inhibitors.

WT induces cell-cycle arrest and inhibits the cell growth on BEL-7402 cells by modulating Akt and ERK1/2 phosphorylation (Zhang et al., 2009b).

References

Zhang Y, Zhang GB, Xu XM, et al. (2012). Suppression of growth of A549 lung cancer cells by waltonitone and its mechanisms of action. Oncol Rep, 28(3):1029-35. doi: 10.3892/or.2012.1869.


Zhang Z, Wang S, Qiu H, Duan C, Ding K, Wang Z (a). (2009). Waltonitone induces human hepatocellular carcinoma cells apoptosis in vitro and in vivo. Cancer Lett, 286(2):223-31. doi: 10.1016/j.canlet.2009.05.023.


Zhang Z, Duan C, Ding K, Wang Z (b). (2009). WT inhibit human hepatocellular carcinoma BEL-7402 cells growth by modulating Akt and ERK1/2 phosphorylation. Zhongguo Zhong Yao Za Zhi, 34(24):3277-80.

Oleanolic Acid (OA)

Cancer:
Pancreatic, hepatocellular carcinoma, prostate, lung, gastric, breast

Action: Radio-sensitizer, pro-apoptotic with 5-FU

Oleanolic acid (OA), a pentacyclic triterpenoid isolated from several plants, including Rosa woodsii (Lindl.), Prosopis glandulosa (Torr.), Phoradendron juniperinum (Engelm. ex A. Gray), Syzygium claviflorum (Roxburgh), Hyptis capitata (Jacq.) and Ternstromia gymnanthera (L.) exhibits potential anti-tumor activity against many tumor cell lines. Mistletoe contains water-insoluble triterpenoids, mainly oleanolic acid, that have anti-tumorigenic effects (StrŸh et al., 2013).

Pancreatic Cancer

Results of a study by Wei et al. (2012) showed that the proliferation of Panc-28 cells was inhibited by OA in a concentration-dependent manner, with an IC50 (The half maximal inhibitory concentration) value of 46.35 µg ml−1. The study also showed that OA could induce remarkable apoptosis and revealed that OA could induce Reactive Oxygen Species (ROS) generation, mitochondrial depolarization, release of cytochrome C, lysosomal membrane permeabilization and leakage of cathepin B. Further study confirmed that ROS scavenger vitamin C could reverse the apoptosis induced by OA in Panc-28 cells.

These results provide evidence that OA arrests the cell-cycle and induces apoptosis, possibly via ROS-mediated mitochondrial and a lysosomal pathway in Panc-28 cell.

The effects of the combination of OA and 5-fluorouracil (5-FU) on Panc-28 human pancreatic cells showed that combined use synergistically potentiated cell death effects on these cells, and that the pro-apoptotic effects were also increased. The expression of apoptosis related proteins was also affected in cells treated with the combination of OA and 5-FU, including activation of caspases-3 and the expression of Bcl-2/Bax, survivin and NF-κB (Wei et al., 2012).

Radio-sensitizer

The combined treatment of radiation with OA significantly decreased the clonogenic growth of tumor cells and enhanced the numbers of intracellular MN compared to irradiation alone. Furthermore, it was found that the synthesis of cellular GSH was inhibited concomitantly with the down-regulation of γ-GCS activity. Therefore, the utilization of OA as a radio-sensitizing agent for irradiation-inducing cell death offers a potential therapeutic approach to treat cancer (Wang et al., 2013).

Prostate Cancer, Lung Cancer, Gastric Cancer, Breast Cancer

Twelve derivatives of oleanolic acid (OA) have been synthesized and evaluated for their inhibitory activities against the growth of prostate PC3, breast MCF-7, lung A549, and gastric BGC-823 cancer cells by MTT assays. Within these series of derivatives, compound 17 exhibited the most potent cytotoxicity against PC3 cell line (IC50=0.39 µM) and compound 28 displayed the best activity against A549 cell line (IC50=0.22 µM). SAR analysis indicates that H-donor substitution at C-3 position of oleanolic acid may be advantageous for improvement of cytotoxicity against PC3, A549 and MCF-7 cell lines (Hao et al., 2013).

Hepatocellular Carcinoma

OA induced G2/M cell-cycle arrest through p21-mediated down-regulation of cyclin B1/cdc2. Cyclooxygenase-2 (COX-2) and p53 were involved in OA-exerted effect, and extracellular signal-regulated kinase-p53 signaling played a central role in OA-activated cascades responsible for apoptosis and cell-cycle arrest. OA demonstrated significant anti-tumor activities in hepatocellular carcinoma (HCC) in vivo and in vitro models. These data provide new insights into the mechanisms underlying the anti-tumor effect of OA (Wang et al., 2013).

References

Hao J, Liu J, Wen X, Sun H. (2013). Synthesis and cytotoxicity evaluation of oleanolic acid derivatives. Bioorg Med Chem Lett, 23(7):2074-7. doi: 10.1016/j.bmcl.2013.01.129.


StrŸh CM, JŠger S, Kersten A, et al. (2013). Triterpenoids amplify anti-tumoral effects of mistletoe extracts on murine B16.f10 melanoma in vivo. PLoS One, 8(4):e62168. doi: 10.1371/journal.pone.0062168.


Wang J, Yu M, Xiao L, et al. (2013). Radio-sensitizing effect of oleanolic acid on tumor cells through the inhibition of GSH synthesis in vitro. Oncol Rep, 30(2):917-24. doi: 10.3892/or.2013.2510.


Wang X, Bai H, Zhang X, et al. (2013). Inhibitory effect of oleanolic acid on hepatocellular carcinoma via ERK-p53-mediated cell-cycle arrest and mitochondrial-dependent apoptosis. Carcinogenesis, 34(6):1323-30. doi: 10.1093/carcin/bgt058.


Wei JT, Liu M, Liuz, et al. (2012). Oleanolic acid arrests cell-cycle and induces apoptosis via ROS-mediated mitochondrial depolarization and lysosomal membrane permeabilization in human pancreatic cancer cells. Journal of Applied Toxicology, 33(8):756–765. doi: 10.1002/jat.2725


Wei J, Liu H, Liu M, et al. (2012). Oleanolic acid potentiates the anti-tumor activity of 5-fluorouracil in pancreatic cancer cells. Oncol Rep, 28(4):1339-45. doi: 10.3892/or.2012.1921.

Moscatilin

Cancers:
Colon, lung, placenta, stomach, breast metastasis

Action: Anti-angiogenic, anti-metastatic, anti-tubulin, cytostatic, cytotoxic, cell-cycle arrest, anti-inflammatory

Stomach Cancer, Lung Cancer, Placental

The efficacy of using moscatilin, a natural anti-platelet agent extracted from the stems of Dendrobrium loddigesii, as an anti-cancer agent was studied. Results demonstrated that moscatilin exerts potent cytotoxic effect against cancer cell lines derived from different tissue origins, including those from the placenta, stomach, and lung, but not those from the liver. In addition, the mechanism of action of moscatilin may be related to its ability to induce a G2 phase arrest in responsive cells.

However, unlike some G2 arresting agents, moscatilin has no detectable inhibitory effect on cyclin B–cdc-2 kinase activity. Thus, the precise nature of its cytotoxic mechanism remains to be determined.

Results suggest that moscatilin is potentially efficacious for chemo-prevention and/or chemotherapy against some types of cancer (Ho & Chen, 2003).

Colorectal Cancer

The growth inhibition of moscatilin was screened on several human cancer cell lines. The effect of moscatilin on tubulin was detected in vitro. Following moscatilin treatment on colorectal HCT-116 cells, c-Jun NH(2)-terminal protein kinase (JNK) and caspase activation was studied by Western blot analysis, and DNA damage was done by Comet assay. Moscatilin induced a time-dependent arrest of the cell-cycle at G2/M, with an increase of cells at sub-G1. Moscatilin inhibited tubulin polymerization, suggesting that it might bind to tubulins. A parallel experiment showed that SP600125 significantly inhibits Taxol and vincristine induced HCT-116 cell apoptosis. This suggests that the JNK activation may be a common mechanism for tubulin-binding agents.

Collectively, results suggest that moscatilin induces apoptosis of colorectal HCT-116 cells via tubulin depolymerization and DNA damage leading to the activation of JNK and mitochondria-involved intrinsic apoptosis pathway (Chen et al., 2008).

Anti-inflammatory

Results showed that moscatilin (10-100 microM) had a significant inhibition in a concentration-dependent manner on pro-inflammatory enzymes (COX-2 and iNOS) expression and macrophage activation under LPS (100 ng/mL) treatment.

Hypoxia-inducible factor 1 (HIF-1) alpha was reported to initiate inflammation under cytokine stimulation or hypoxic conditions. Moscatilin had significant inhibition on HIF-1 expression via down-regulation of HIF-1 mRNA without affecting cell viability, translation machinery, or proteasome-mediated degradation of HIF-1. Collective data demonstrarted that moscatilin inhibited both COX-2 and iNOS expressions after LPS treatment in RAW264.7. Furthermore, moscatilin's inhibitory effect appears to be dependent on the repression of HIF-1alpha accumulation and NF-kappaB activation (Liu et al., 2010).

Lung Cancer; Angiogenesis

Moscatilin significantly inhibited growth of lung cancer cell line A549 (NSCLC) and suppressed growth factor-induced neovascularization. In addition, VEGF- and bFGF-induced cell proliferation, migration, and tube formation of HUVECs was markedly inhibited by moscatilin. Western blotting analysis of cell signaling molecules indicated that moscatilin inhibited ERK1/2, Akt, and eNOS signaling pathways in HUVECs.

Results suggest that inhibition of angiogenesis by moscatilin may be a major mechanism in cancer therapy (Tsai et al., 2010).

Lung Cancer

Investigation demonstrated that non-toxic concentrations of moscatilin were able to inhibit human non-small-cell lung cancer H23 cell migration and invasion. The inhibitory effect of moscatilin was associated with an attenuation of endogenous reactive oxygen species (ROS), in which hydroxyl radical was identified as a dominant species in the suppression of filopodia formation.

Results indicate a novel molecular basis of moscalitin inhibiting lung cancer cell motility and invasion. Moscalitin may have promising anti-metastatic potential as an agent for lung cancer therapy (Kowitdamrong, Chanvorachote, Sritularak & Pongrakhananon, 2013).

Breast Cancer; Metastasis

Moscatilin, derived from the orchid Dendrobrium loddigesii, has shown anti-cancer activity. The mechanism by which moscatilin suppresses the migration and metastasis of human breast cancer MDA-MB-231 cells in vitro and in vivo was evaluated.

Moscatilin was found to significantly inhibit breast cancer MDA-MB-231 cell migration by using scratch assays and Boyden chambers.

In an MDA-MB-231 metastatic animal model, moscatilin (100 mg/kg) significantly suppressed breast cancer metastasis to the lungs and reduced the number of metastatic lung nodules and lung weight without causing any toxicity.

Results indicated that moscatilin inhibited MDA-MB-231 cell migration via Akt- and Twist-dependent pathways, consistent with moscatilin's anti-metastatic activity in vivo. Therefore, moscatilin may be an effective compound for the prevention of human breast cancer metastasis (Pai et al., 2013).

References

Chen TH, Pan SL, Guh JH, et al. (2008). Moscatilin induces apoptosis in human colorectal cancer cells: a crucial role of c-Jun NH2-terminal protein kinase activation caused by tubulin depolymerization and DNA damage. Clinical Cancer Research, 14(13), 4250-4258. doi: 10.1158/1078-0432.CCR-07-4578.


Ho CK, Chen CC. (2003). Moscatilin from the orchid Dendrobrium loddigesii is a potential anti-cancer agent. Cancer Investigation, 21(5), 729-736.


Kowitdamrong A, Chanvorachote P, Sritularak B, Pongrakhananon V. (2013). Moscatilin inhibits lung cancer cell motility and invasion via suppression of endogenous reactive oxygen species. BioMed Research International., 2013, 765894. doi: 10.1155/2013/765894.


Liu YN, Pan SL, Peng CY, et al. (2010). Moscatilin repressed lipopolysaccharide-induced HIF-1alpha accumulation and NF-kappaB activation in murine RAW264.7 cells. Shock, 33(1), 70-5. doi: 10.1097/SHK.0b013e3181a7ff4a.


Pai HC, Chang LH, Peng CY, et al. (2013). Moscatilin inhibits migration and metastasis of human breast cancer MDA-MB-231 cells through inhibition of Akt and Twist signaling pathway.

Journal of Molecular Medicine (Berlin), 91(3), 347-56. doi: 10.1007/s00109-012-0945-5.

Tsai AC, Pan SL, Liao CH, et al. (2010). Moscatilin, a bibenzyl derivative from the India orchid Dendrobrium loddigesii, suppresses tumor angiogenesis and growth in vitro and in vivo. Cancer Letters, 292(2), 163-70. doi: 10.1016/j.canlet.2009.11.020.

Dauricine

Cancer: Prostate, urinary system, breast, lung

Action: MDR

Lung Cancer

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

Prostate Cancer

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

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

Breast Cancer

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

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

Breast Cancer; MDR

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

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

MDR

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

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

References

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

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

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

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

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

Shikonin

Cancer: Sarcoma-180, lung, melanoma, leukemia

Action: Anti-inflammatory, inhibits angiogenesis, MDR

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

Melanoma

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

Anti-inflammatory

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

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

Leukemia, MDR

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

Lung Cancer

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

MDR

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

References

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


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


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


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


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


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


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

Isorhamnetin

Cancer:
Lung, colon, acute myeloid leukemia, T lymphoma, Ehrlich carcinoma, gastric, esophageal squamous cell, chronic myelogenous leukemia

Action: Dox-induced cardiotoxicity, anti-oxidant

Isorhamnetin, the anti-tumor component of Hippophae rhamnoides Linn, is also a member of the ßavonoid class of compounds. Its chemical name is 3,5,7-trihydroxy-2-(4-hydroxy-3-methoxyphenyl) chromen-4-one and its molecular formula is C16H12O7.

Lung Cancer

Isorhamnetin shows good inhibitory effects on human lung adenocarcinoma A549 cells, human colon cancer HT-29 cells, human chronic myeloid leukemia K562 cells, human acute myeloid leukemia HL-60 cells, mouse T lymphoma YAC-1 cells and mouse Ehrlich carcinoma. In terms of its mechanism of action, it seems that isorhamnetin simultaneously reduces the expression of Bcl-2 and increases the expression of Bax, which activates caspase-9 and its downstream factor caspase-3, thus resulting in cell death (Zhu et al. 2005).

Colorectal Cancer

It was demonstrated that isorhamnetin prevents colorectal tumorigenesis. Dietary isorhamnetin decreased mortality, tumor number, and tumor burden by 62%, 35%, and 59%, respectively. Magnetic resonance imaging, histopathology, and immunohistochemical analysis revealed that dietary isorhamnetin resolved the DSS-induced inflammatory response faster than control diet.

These observations suggest the chemo-protective effects of isorhamnetin in colon cancer are linked to its anti-inflammatory activities and its inhibition of oncogenic Src activity and consequential loss of nuclear β-catenin, activities that are dependent on CSK expression (Saud et al., 2013).

Gastric Cancer

The potential effects of isorhamnetin (IH), a 3'-O-methylated metabolite of quercetin, were investigated on the peroxisome proliferator-activated receptor γ (PPAR-γ) signaling cascade using proteomics technology platform, gastric cancer (GC) cell lines, and xenograft mice model.

It was observed that IH exerted a strong anti-proliferative effect and increased cytotoxicity in combination with chemotherapeutic drugs. IH also inhibited the migratory/invasive properties of gastric cancer cells, which could be reversed in the presence of PPAR-γ inhibitor.

Using molecular docking analysis, Ramachandran et al. (2013) demonstratd that IH formed interactions with seven polar residues and six nonpolar residues within the ligand-binding pocket of PPAR-γ that are reported to be critical for its activity and could competitively bind to PPAR-γ. IH significantly increased the expression of PPAR-γ in tumor tissues obtained from xenograft model of GC. Overall, these findings clearly indicate that anti-tumor effects of IH may be mediated through modulation of the PPAR-γ activation pathway in GC.

Cardiac-protective; Doxorubicin

Isorhamnetin is a natural anti-oxidant with obvious cardiac-protective effect. Its action against doxorubicin-induced cardotoxicity and underlying mechanisms were investigated. Doxorubicin (Dox) is an anthracycline antibiotic for cancer therapy with limited usage due to cardiotoxicity. The aim of this study is to investigate the possible protective effect of isorhamnetin against Dox-induced cardiotoxicity and its underlying mechanisms. In an in vivo investigation, rats were intraperitoneally (i.p.) administered with Dox to duplicate the model of Dox-induced chronic cardiotoxicity.

Daily pre-treatment with isorhamnetin (5 mg/kg, i.p.) for 7 days was found to reduce Dox-induced myocardial damage significantly, including the decline of cardiac index, decrease in the release of serum cardiac enzymes, and amelioration of heart vacuolation. In vitro studies on H9c2 cardiomyocytes, isorhamnetin was effective to reduce Dox-induced cell toxicity. Isorhamnetin also potentiated the anti-cancer activity of Dox in MCF-7, HepG2 and Hep2 cells. These findings indicated that isorhamnetin can be used as an adjuvant therapy for the long-term clinical use of Dox (Sun et al., 2013).

Chronic Myelogenous Leukemia

The isorhamnetin 3-o-robinobioside and its original extract, ethyl acetate extract, from Nitraria retusa leaves, were evaluated for their ability to induce anti-oxidant and anti-genotoxic effects in human chronic myelogenous leukemia cell line. They were shown to have a great anti-oxidant and anti-genotoxic potential on human chronic myelogenous leukemia cell line K562 (Boubaker et al., 2012).

Esophageal Cancer

The flavonol aglycone isorhamnetin shows anti-proliferative activity in a variety of cancer cells and it inhibits the proliferation of human esophageal squamous carcinoma Eca-109 cells in vitro (Shi et al., 2012).

Cancer:
Actions: Overcomes MDR; P-glycoproteins, breast cancer resistance proteins (BCRP), efflux transporters

Flavonoid isorhamnetin occurs in various plants and herbs, and demonstrates various biological effects in humans. This work will clarify the isorhamnetin absorption mechanism using the Caco-2 monolayer cell model. The isorhamnetin transport characteristics at different concentrations, pHs, temperatures, tight junctions and potential transporters were systemically investigated.

Isorhamnetin was poorly absorbed by both passive diffusion and active transport mechanisms. Both trans- and paracellular pathways were involved during isorhamnetin transport. Active transport under an ATP-dependent transport mechanism was mediated by the organic anion transporting peptide (OATP); isorhamnetin’s permeability from the apical to the basolateral side significantly decreased after estrone-3-sulfate was added (p<0.01).

Efflux transporters, P-glycoproteins (P-gp), breast cancer resistance proteins (BCRP) and multidrug resistance proteins (MRPs) participated in the isorhamnetin transport process. Among them, the MRPs (especially MRP2) were the main efflux transporters for isorhamnetin; transport from the apical to the basolateral side increased 10.8-fold after adding an MRP inhibitor (MK571).

References

Boubaker J, Ben Sghaier M, Skandrani I, et al. (2012). Isorhamnetin 3-O-robinobioside from Nitraria retusa leaves enhance anti-oxidant and anti-genotoxic activity in human chronic myelogenous leukemia cell line K562. BMC Complement Altern Med, 12:135. doi: 10.1186/1472-6882-12-135.


Ramachandran L, Manu KA, Shanmugam MK, et al. (2013). Isorhamnetin inhibits proliferation and invasion and induces apoptosis through the modulation of peroxisome proliferator-activated receptor γ activation pathway in gastric cancer. J Biol Chem, 288(26):18777. doi: 10.1074/jbc.A112.388702.


Saud SM, Young MR, Jones-Hall YL, et al. (2013). Chemo-preventive activity of plant flavonoid isorhamnetin in colorectal cancer is mediated by oncogenic Src and β -catenin. Cancer Res, 73:5473.


Shi C, Fan LY, Cai Z, Liu YY, Yang CL. (2012). Cellular stress response in Eca-109 cells inhibits apoptosis during early exposure to isorhamnetin. Neoplasma, 59(4):361-9. doi: 10.4149/neo_2012_047.


Sun J, Sun G, Meng X, et al. (2013). Isorhamnetin protects against doxorubicin-induced cardiotoxicity in vivo and in vitro. PLoS One, 8(5):e64526. doi: 10.1371/journal.pone.0064526.


Zhu L, Wang ZR, Zhou LM, et al. (2005). Effects and mechanisms of isorhamnetin on lung carcinoma. Space Med Med Eng (Chin), 18:381-383.


Duan J, Xie Y, Luo H, Li G, Wu T, Zhang T. (2014) Transport characteristics of isorhamnetin across intestinal Caco-2 cell monolayers and the effects of transporters on it. Food Chem Toxicol. 2014 Apr;66:313-20. doi: 10.1016/j.fct.2014.02.003.

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.

Fucoidan

Cancer:
Lymphoma, prostate, hepatocellular carcinoma, breast, colorectal

Action: Chemotherapy protective

Fucoidan is a ulphated polysaccharide found in brown seaweed, including Sargassum thunbergii [(Mertens ex Roth) Kuntze] and Fucus vesiculosus (L.).

Lymphoma

Fucoidan, a sulfated polysaccharide in brown seaweed, was found to inhibit proliferation and induce apoptosis in human lymphoma HS-Sultan cell lines. Fucoidan-induced apoptosis was accompanied by the activation of caspase-3 and was partially prevented by pre-treatment with a pan-caspase inhibitor, z-VAD-FMK. The neutralizing antibody, Dreg56, against human l-selectin, did not prevent the inhibitory effect of fucoidan on the proliferation of IM9 and MOLT4 cells, both of which express l-selectin; thus it is possible fucoidan induced apoptosis through different receptors. These results demonstrate that fucoidan has direct anti-cancer effects on human HS-Sultan cells through caspase and ERK pathways (Aisa et al., 2005).

Colorectal Cancer; Chemotherapy

A total of 20 patients with unresectable advanced or recurrent colorectal cancer scheduled to undergo treatment with FOLFOX or FOLFIRI were randomly allocated into a fucoidan treatment group (n=10) and a control group without fucoidan treatment (n=10). Results showed that fucoidan regulated the occurrence of fatigue during chemotherapy. Chemotherapy with fucoidan was continued for a longer period than chemotherapy without fucoidan. Additionally, the survival of patients with fucoidan treatment was longer than that of patients without fucoidan, although the difference was not significant.

Thus, fucoidan may enable the continuous administration of chemotherapeutic drugs for patients with unresectable advanced or recurrent colorectal cancer, and as a result, the prognosis of such patients is prolonged (Ikeguchi et al., 2011).

Prostate Cancer

Fucoidan obtained from Undaria pinnatifida induced the apoptosis of PC-3 cells by activating both intrinsic and extrinsic pathways. The induction of apoptosis was accompanied by the activation of extracellular signal-regulated kinase mitogen-activated protein kinase (ERK1/2 MAPK) and the inactivation of p38 MAPK and phosphatidylinositol 3-kinase (PI3K)/Akt. In addition, fucoidan also induced the up-regulation of p21Cip1/Waf and down-regulation of E2F-1 cell-cycle-related proteins. Furthermore, in the Wnt/β-catenin pathway, fucoidan activated GSK-3β that resulted in the decrease of β-catenin level, followed by the decrease of c-myc and cyclin D1 expressions, target genes of β-catenin in PC-3 cells. The data support that fucoidan might have potential for the treatment of prostate cancer (Boo et al., 2013).

Hepatocellular Carcinoma

Fucoidan isolated from U. pinnatifida induced apoptosis in human hepatocellular carcinoma SMMC-7721 cells via the ROS-mediated mitochondrial pathway. SMMC-7721 cells exposed to fucoidan displayed growth inhibition and several typical features of apoptotic cells, such as chromatin condensation and marginalization, and a decrease in the number of mitochondria, and in mitochondrial swelling and vacuolation (Yang et al., 2013).

Breast Cancer

Fucoidan exerts its anti-cancer activity through down-regulation of Wnt/β-catenin signaling. Fucoidan may be an effective therapy for the chemoprevention and treatment of mouse breast cancer. Fucoidan significantly inhibited cell growth, increased cell death, and induced G1 cell- cycle arrest in breast cancer 4T1 cells. Fucoidan also reduced β-catenin expression and T cell factor/lymphoid-enhancing factor reporter activity. Furthermore, fucoidan down-regulated the expression of downstream target genes such as c-myc, cyclin D1, and survivin (Xue et al., 2013).

References

Aisa Y, Miyakawa Y, Nakazato T, Shibata H, et al. (2005). Fucoidan induces apoptosis of human HS-Sultan cells accompanied by activation of caspase-3 and down-regulation of ERK Pathways. Am. J. Hematol, 78:7–14. doi: 10.1002/ajh.20182.


Boo HJ, Hong JY, Kim SC, et al. (2013). The anti-cancer effect of fucoidan in PC-3 prostate cancer cells. Mar Drugs, 11(8):2982-99. doi: 10.3390/md11082982.


Ikeguchi M, Yamamoto M, Arai Y, et al. (2011). Fucoidan reduces the toxicities of chemotherapy for patients with unresectable advanced or recurrent colorectal cancer. Oncology Letters, 2(2). doi: 10.3892/ol.2011.254.


Xue M, Ge Y, Zhang J, et al. (2013). Fucoidan inhibited 4T1 mouse breast cancer cell growth in vivo and in vitro via down-regulation of Wnt/β -catenin signaling. Nutr Cancer, 65(3):460-8. doi: 10.1080/01635581.2013.757628.


Yang L, Wang P, Wang H, et al. (2013). Fucoidan derived from Undaria pinnatifida induces apoptosis in human hepatocellular carcinoma SMMC-7721 cells via the ROS-mediated mitochondrial pathway. Mar Drugs, 11(6):1961-76. doi: 10.3390/md11061961.