• Journal of Nutrition and Health
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• v.35 no.2
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• pp.192-200
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• 2002

Conjugated linoleic acid (CLA) is a collective term for positional and geometric isomers of octadecadienoic acid in which the double bonds are conjugated. CLA has anticancer activity in a variety of animal cancer models, and cis-9, trans-11 (c9t11) and trans-10, cis-12(t10c12) CLA are the most predominant isomers present in the synthetic preparations utilized in these animal studies. To compare the ability of c9t11, t10c12 and an isomeric mixture of CLA to inhibit TSU-Prl cell growth, cells were incubated in a serum-free medium with various concentrations of these fatty acids. The isomeric mixture inhibited cell growth in a dose-dependent manner (1-3 $\mu$M) with a 41 $\pm$ 1% inhibition observed at 3 $\mu$M concentration after 48 hours. T10c12 also inhibited cell proliferation in a dote-dependent manner, However, the efficacy and potency of this isomer was much greater than that of the isomeric mixture with a 49 $\pm$ 2% inhibition observed at 0.3 $\mu$M concentration after 48 hours. By contrast, c9t11 slightly increased cell proliferation. To determine whether the growth-inhibiting effect of CLA is related to the changes in production of insulin-like growth factors (IGF) and IGF-binding proteins (IGFBP) by these cells, serum-free conditioned media were collected. Immunoblot analysis of conditioned media using a monoclonal anti-IGF-II antibody showed that both the isomeric mixture and t10c12 inhibited secretion of both mature 7,500 Mr and higher Mr forms of pro IGF-II, whereas c9t11 had no effect. Ligand blot analysis with 125I-IGF-II revealed the presence of two types of IGFBPs : 24,000 Mr IGFBP-4 and 30,000 Mr IGFBP-6. The production of IGFBP-4 slightly decreased at the highest concentrations of the isomeric mixture and t10c12. These results indicate that CLA inhibits human prostate cancer cell growth, an effect largely due to the action of t10c12. The growth inhibition may result, at least in part, from decreased production of IGF-II and IGFBP-4 by these cells.

• Journal of Life Science
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• v.20 no.11
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• pp.1738-1741
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• 2010

Caliper measurements of tumor volume have been widely used in the assessment of tumors in animal models. However, experiments based on caliper data have resulted in unreliable estimates of tumor growth, due to necrotic areas of tumor mass. To overcome this systematic bias, we engineered a new luciferase-expressing rat prostate cancer cell line (MLL-Luc) that produces bioluminescence from viable cancer cells. MLL-Luc cells showed a strong correlation between bioluminescence intensity and cell number ($R^2$=0.99) and also accurately quantified tumor growth, with reduced bioluminescence signals caused by necrotic cells in a subcutaneous MLL-Luc xenograft model. The accurate quantification of tumor growth with bioluminescence imaging (BLI) was confirmed by a better antitumor effect of combination chemotherapy, compared to that based on caliper measurements with a correlation between the bioluminescence signal and tumor volume ($R^2$=0.84). These data suggest that bioluminescent MLL xenografts are a powerful and quantitative tool for monitoring tumor growth and are useful in evaluating the efficacy of anticancer drugs, with less systematic bias.

• Journal of Physiology & Pathology in Korean Medicine
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• v.25 no.6
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• pp.968-974
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• 2011

Saussurea lappa Clarke is a well-known transitional medicine in Asia including Korea, China and Japan. It has been reported that Clarke has diverse effects such as anti-viral, anti-inflammatory, anti-cancer in human gastric cells and human prostate cancer cells. However, the anti-cancer effects and the mechanism of actions of Saussurea lappa Clarke are still unknown in breast cancer. In this study, we observed that Saussurea lappa Clarke inhibits the cell growth in a dose- and time-dependent manner in highly-metastatic MDA-MB-231 breast cancer cells. In order to examine whether Saussurea lappa Clarke suppresses cell growth inducing apoptosis cell death or cell cycle arrest, we analyzed DNA contents and cell cycle distribution using a flow cytometer and western blotting in MDA-MB-231 cells. We suggest that Saussurea lappa Clarke dose not induced apoptosis and induced G2/M phase cell cycle arrest. Moreover, Saussurea lappa Clarke also decreased the expression level of metastasis-angiogenesis releated protein such as VEGF. However, dose not changed the expression level of metastasis related protease MMP-1 in highly-metastatic MDA-MB-231 breast cancer cells. Therefore, Saussurea lappa Clarke might be good and useful chemotherapy agent highly-metastatic breast cancer patients.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6541-6548
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• 2013

Pigmented rice is mainly black, red, and dark purple, and contains a variety of flavones, tannin, polyphenols, sterols, tocopherols, ${\gamma}$-oryzanols, amino acids, and essential oils. The present study evaluated the cytotoxic effects of purple rice extracts (PREs) combined with chemotherapeutic drugs on human cancer cells and mechanisms of cell death. Methanolic (MeOH) and dichloromethane (DCM) extracts of three cultivars of purple rice in Thailand: Doisaket (DSK), Nan and Payao (PYO), were tested and compared with white rice (KK6). Cytotoxicity was determined by 3-(4, 5-dimethyl)-2, 5-diphenyltetrazolium bromide (MTT) assay in human hepatocellular carcinoma HepG2, prostate cancer LNCaP and murine normal fibroblast NIH3T3 cells. MeOH-PYO-PRE was the most cytotoxic and inhibited HepG2 cell growth more than that of LNCaP cells but was not toxic to NIH3T3 cells. When PREs were combined with paclitaxel or vinblastine, they showed additive cytotoxic effects on HepG2 and LNCaP cells, except for MeOH-PYO-PRE which showed synergistic effects on HepG2 cells when combined with vinblastine. MeOH-PYO-PRE plus vinblastine induced HepG2 cell apoptosis with loss of mitochondrial transmembrane potential (MTP) but no ROS production. MeOH-PYO-PRE-treated HepG2 cells underwent apoptosis via caspase-9 and-3 activation. The level of ${\gamma}$-oryzanol was highest in DCM-PYO-PRE (44.17 mg/g) whereas anthocyanin content was high in MeOH-PYO-PRE (5.80 mg/g). In conclusion, methanolic Payao purple rice extract was mostly toxic to human HepG2 cells and synergistically enhanced the cytotoxicity of vinblastine. Human HepG2 cell apoptosis induced by MeOH-PYO-PRE and vinblastine was mediated through a mitochondrial pathway.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.10
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• pp.4469-4475
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• 2015

Transient receptor potential melastain 7 (TRPM7) is a bifunctional protein with dual structure of both ion channel and protein kinase, participating in a wide variety of diseases including cancer. Recent researches have reported the mechanism of TRPM7 in human cancers. However, the correlation between TRPM7 and prostate cancer (PCa) has not been well studied. The objective of this study was to investigate the potential the role of TRPM7 in the apoptosis of PC-3 cells, which is the key cell of advanced metastatic PCa. In this study, we demonstrated the influence and potential function of TRPM7 on the PC-3 cells apoptosis induced by TNF-related apoptosis inducing-ligand (TRAIL). The study also found a novel up-regulated expression of TRPM7 in PC-3 cells after treating with TRAIL. Suppression of TRPM7 by TRPM7 non-specific inhibitors ($Gd^{3+}$ or 2-aminoethoxy diphenylborate (2-APB) ) not only markedly eliminated TRPM7 expression level, but also increased the apoptosis of TRAIL-treated PC-3 cells, which may be regulated by the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway accompany with up-regulated expression of cleaved Caspase-3, (TRAIL-receptor 1, death receptors 4) DR4, and (TRAIL-receptor 2, death receptors 5) DR5. Taken together, our findings strongly suggested that TRPM7 was involved in the apoptosis of PC-3 cells induced by TRAIL, indicating that TRPM7 may be applied as a therapeutic target for PCa.

• Proceedings of the Korean Society of Toxicology Conference
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• 2001.05a
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• pp.9-13
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• 2001

Genistein, a natural isoflavonoid phytoestrogen, is a strong inhibitor of protein tyrosine kinase and DNA topoisomerase II activities. Genistein has been shown to have anticancer proliferation, differentiation and chemopreventive effects. In the present study, we have addressed the mechanism of action by which genistein suppressed the proliferation of p53-null human prostate carcinoma cells.(omitted)

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.5
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• pp.2087-2092
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• 2015

Nowadays herbal-derived medicines are attracting attention as new sources of drugs with few side effects. Silibinin is a flavonoid compound with chemotheraputic effects on different cancers such as examples in the prostate, lung, colon and breast. In the present study, the cytotoxic effects of silibinin on MCF7 breast cancer cells were investigated. Apoptosis was determined by flow cytometry and the impact of silibinin on the expression of pivotal genes including Bak, P53, P21, BRCA1, BCL-X1 and ATM was analyzed. Treatment for 24h had a significant dose-dependent inhibitory effect on cell growth (p<0.05) with dose- and time- dependent induction of apoptosis (p<0.05). In addition, there were significant increases in BRCA1, ATM, Bak and Bcl-XL gene expression at the mRNA level with different concentrations of silibinin for 24 or 48 h (p<0.05). Taken together, the results suggest that silibinin inhibits the proliferation and induces apoptosis of MCF-7 cells by down-regulating Bak, P53, P21, BRCA1, BCL-Xl and thus may be considered as an effective adjuvant drug to produce a better chemopreventive response for the cancer therapy.

• Archives of Pharmacal Research
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• v.29 no.8
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• pp.633-644
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• 2006

In last couple of decades the use of natural compounds like flavonoids as chemopreventive agents has gained much attention. Our current study focuses on identifying chemopreventive flavonoids and their mechanism of action on human prostate cancer cells. Human prostate cancer cells (PC3), stably transfected with activator protein 1 (AP-1) luciferase reporter gene were treated with four main classes of flavonoids namely flavonols, flavones, flavonones, and isoflavones. The maximum AP-1 luciferase induction of about 3 fold over control was observed with $20\;{\mu}M$ concentrations of quercetin, chrysin and genistein and $50\;{\mu}M$ concentration of kaempferol. At higher concentrations, most of the flavonoids demonstrated inhibition of AP-1 activity. The MTS assay for cell viability at 24 h showed that even at a very high concentration $(500\;{\mu}M)$, cell death was minimal for most of the flavonoids. To determine the role of MAPK pathway in the induction of AP-1 by flavonoids, Western blot of phospho MAPK proteins was performed. Four out of the eight flavonoids namely kaempferol, apigenin, genistein and naringenin were used for the Western Blot analysis. Induction of phospho-JNK and phospho-ERK activity was observed after two hour incubation of PC3-AP1 cells with flavonoids. However no induction of phospho-p38 activity was observed. Furthermore, pretreating the cells with specific inhibitors of JNK reduced the AP-1 luciferase activity that was induced by genistein while pretreatment with MEK inhibitor reduced the AP-1 luciferase activity induced by kaempferol. The pharmacological inhibitors did not affect the AP-1 luciferase activity induced by apigenin and naringenin. These results suggest the possible involvement of JNK pathway in genistein induced AP-1 activity while the ERK pathway seems to play an important role in kaempferol induced AP-1 activity.

• Journal of Life Science
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• v.19 no.1
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• pp.9-14
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• 2009

The prostate cancer is the critical health problem, increasing of its related death in worldwide. Unfortunately present surgery and chemotherapeutic choices seem to be impossible in curing or controlling prostate cancer, because metastasis occasionally advances even after these potentially curative therapies. Therefore, there is immediate need to alternative chemoprevention and chemotherapeutic agents. Over one hundred species of dried medicinal herbs were tested for proliferation inhibitory effects on prostate cancer cell line, PC-3. One of them, Anthriscus sylvestris was selected because of potent anti-proliferation effect. The dried root of A. sylvestris was extracted with 100% methanol for 2-3 days and its extract was fractionated by using ethyl acetate. And ethyl acetate layer was subjected to column chromatographies on silica gel, reverse phase-18 (RP-18) and Sephadex LH-20, in turn. Finally, the pure compound was obtained by crystallization in methanol at $4^{\circ}C$ for overnight and identified as deoxypodophyllotoxin by NMR spedorscopic and physico-chemical analyses. In addition, it was confirmed that deoxypodophyllotoxin clearly inhibits the proliferation of PC-3 cells in a dose and time-dependent manner.

• Journal of Physiology & Pathology in Korean Medicine
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• v.26 no.4
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• pp.519-526
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• 2012

Recently, herbal flavonoids have been implicated for anti-cancer therapy. Flavonoids as a commonly known for their anti-oxidant activity, are contained in the herbal medicine as well as root of plants, vegetables, fruits, grains, tea, and wine. Kaempferol, a component of Polygonati rhizoma, a member of the herbal flavonoids, has been studied for anti-hypercholesterol, anti-hypertension and anti-diabetes. It is also known to be effective in anti-cancer therapy for breast, prostate and other type of cancers. However, the anti-cancer therapeutic mechanisms are pooly understood. Here, we investigated the molecular mechanism underlying kaempferol-induced anti-cancer effects using the human liver cancer cell lines, Hep3B, HepG2, and Sk-Hep-1, and human Chang liver cell as a control. As shown by the FACS analysis, measurement of caspase activity, DAPI and trypan blue staining, and DNA fragmentation assay, kaempferol induced apoptosis in the liver cancer cells with the greater potential in Hep3B cells than other liver cancer cells. In addition, we performed microarray analysis to profile the genome-wide mRNA expression regulated by kaempferol. Many of the apoptosis-related genes were significantly induced in kaempferol-treated Hep3B cells, in particular, the genes associated with MAPK cascade. Additionally, kaempferol induced the mRNA expression of genes involved in MKK7-JNK cascade, MKK3-p38 cascade, and caspase signaling pathway, which are all known to trigger apoptosis. Overall, our data suggest that kaempferol has anti-liver cancer effects by inducing apoptosis through the MKK7-JNK cascade, MKK3-p38 cascade, and caspase signaling pathways.