• Archives of Pharmacal Research
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• v.25 no.5
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• pp.685-690
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• 2002

The mitogen-stimulated serine/threonine kinase $p70^{S6k}$ plays an important role in the progression of cells from $G_0/G$_1$$ to S phase of the cell cycle by translational up-regulation of a family of mRNA transcripts family of mRNA transcripts which contain polypyrimidine tract at their 5 transcriptional start site. Here, we report that $p70^{S6k}$ was constitutively phosphorylated and activated to various degrees in serum-deprived AGS, A2058, HT-1376, MG63, MCF7, MDA-MB-435S, MDA-MB-231 and MB-157. Rapamycin treatment induced a significant dephosphorylation and inactivation of $p70^{S6k}$ in all cancer cell lines, while wortmannin, a specific inhibitor of PI3-K, caused a mild dephosphorylation of $p70^{S6k}$ in AGS, MDA-MB-435S and MB-157. In addition, SQ20006, methylxanthine phosphodiesterase inhibitor, reduced the phosphorylation of $p70^{S6k}$ in all cancer cells tested. Consistent with inhibitory effect of rapamycin on $p70^{S6k}$ activity, rapamycin inhibited [$^3H$]-thymidine incorporation and increased the number of cells at $G_{0}G_{1}$ phase. Furthermore, these inhibitory effects were accompanied by the decrease in growth of cancer cells. Taken together, the results indicate that the antiproliferative activity of rapamycin might be attributed to cell cycle arrest at $G_{0}G_{1}$ phase in human cancer cells through the inhibition of constitutively activated $p70^{S6k}$ of cancer cells and suggest $p70^{S6k}$ as a potential target for therapeutic strategies aimed at preventing or inhibiting tumor growth.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.4
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• pp.395-401
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• 2006

In this study, we investigated anticarcinogenic effects of extracts from Gloiopeltis tenax (GT). GT was extracted with methanol (GTM), which was then further fractionated into four fractions by using solvent fractionation method, affording methanol (GTMM), hexane (GTMH), butanol (GTMB) and aqueous (GTMA) soluble fractions. We determined the cytotoxic effects of these fractions on cancer cells by MTT assay. Among various fractions of GT, the GTMM showed the strongest cytotoxic effect at concentration of $150{\mu}g/mL$, displaying 95.97% on HepG2 cell lines and 93.64% on HT-29 cell lines, respectively. And, the anti-proliferative effect of GT was accompanied by a marked in increase of levels of Bad, Bax, Bok and Bak protein and activation of caspase-3, caspase-7 and PARP protein. Also, we observed quinone reductase (QR) induced effects in all fraction layers of GT on HepG2 cells. The QR induced effects of the GTMM and GTMB on HepG2 cells at concentration of $60{\mu}g/mL$ showing inductive indexes of 2.86 and 2.04 compared to the control value of 1.0.

• Food Science and Preservation
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• v.14 no.2
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• pp.220-225
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• 2007

This study was performed to measure the antioxidative, antimutagenic, and cytotoxic properties of Prunus armeniaca using the DPPH (1, 1-diphenyl-2-picrylhydrazyl) free radical donating method, the Ames test, and cytotoxicity measurements, respectively. Electron-donating abilities were 48.3, 43.9, 14.8 and 12.9 per g dry matter of P. armeniaca seed (PAS), P. armeniaca flesh(PAF), butylated hydroxytoluene, and ${\alpha}-tocopherol$, respectively. The direct antimutagenic effects of an ethanol extract of P. armeniaca were examined in Ames tests using Salmonella typhimurium TA98 and TA100 as reporter organisms. In the Ames test, the ethanol extract of P. armenicaca alone did not exhibit any mutagenicity but the extract did show substantial inhibitory effects against mutations induced by N-methyl-N'-nitro-N-nitrosoguanidine(MNNG) and 4-nitroquinoline-1-oxide(4NQO). The ethanol extract of PAS(200g dry matter/plate) inhibited strain TA98 mutagenesis induced by 4NQO by ca. 37.9%, and mutation inhibition values of 42.1% and 69.4%, respectively, were observed when 4NQO and MNNG acted on the TA100 strain. The cytotoxic effects of ethanol extracts of P. armeniaca against cell lines of human lung carcinoma(A549), human breast adenocarcinoma(MCF-7), human hepatocellular carcinoma(Hep3B), human cervical adenocarcinoma(HeLa), and human gastric carcinoma(AGS) rose with increases in extract concentration. An ethanol extract(4mg/mL dry matter) of PAF showed strong cytotoxicities of 88.2%, 58%, 72.8%, 89.4%, and 91.9% against A549, AGS, MCF-7, HeLa, and Hep3B cells, respectively. In contrast, the same extract showed only 13 37% cytotoxicity for a nomal human kiney cell line(293). It is suggested that P. armeniaca possesses useful antioxidative, antimutagenic, and anticancer properties.

• Microbiology and Biotechnology Letters
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• v.34 no.2
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• pp.143-149
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• 2006

A extract from Spirulina platensis of seawater and freshwater was obtained by using the water and ethanol. Extraction yields of seawater S. platensis were observed about 3% higher than freshwater S. platensis. Cytotoxicity (HEK293) and inhibition ratio of cancer cell line (A549, AGS, MCF7, Hep3B) in adding of the extracts from the S. platensis of seawater and freshwater were measured by SRB assay. Cytotoxicity of all of the extracts in adding 1.0 mg/ml was below 26%. Ctotoxicity of the extracts from the seawater S. platensis were about 6% less than freshwater S. platensis. Inhibition ratio of cancer cell growth was inhibited by adding 1.0 mg/ml of the extracts that was obtained about 80%. Inhibition effect of cancer cell growth in adding seawater S. platensis was observed higher than freshwater S. platensis. Differentiation ratio of HL-60 cells in adding the extracts of seawater S. platensis was observed highly that was 160.9%.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.964-969
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• 2000

Di-(2-ethylhexyl) adipate(DEHA) has been used extensively as a plasticizer in the manufacture of plastic products such as PVC films. Though, phthalate esters plasticizers have been known to induce endocrine system-mediated responses, few studies have been conducted for the screening of estrogenic activity of DEHA, an adipate plasticizer. This study was initiated to evaluate the estrogenic activity of DEHA by in vitro E-screen assay and in vivo uterotrophic assay. MCF-7 human breast cancer cells were treated with $DEHA(5{\times}10^{-9}{\sim}5{\times}10^{-4}\;M)$, for 144 hr, and cell proliferation was determined by sulforhodamine B(SRB) assay. DEHA dissolved in corn oil was administered subcutaneously to ovariectomized(OVX) female Sprague-Dawley rats at dosage levels of 0, 2, 20 and 200 mg/kg/day for three consecutive days. Rats were sacrificed 24 hr after final treatment and vagina and uterus(wet and blotted) weights were obtained. E-screen assayed DEHA did not generate cell proliferation at treated concentrations$(5{\times}10^{-9}{\sim}5{\times}10^{-4}\;M)$, whereas 17 ${\beta}-estradiol$(E2), the positive control, induced cell proliferation at low concentrations$(5{\times}10^{-14}{\sim}5{\times}10^{-9}\;M)$. In the uterotrophic assay, DEHA did not change vagina and uterus(wet and blotted) weights at dosage levels up to 200 mg/kg/day treatment. These results demonstrated that DEHA did not exhibit the estrogenic activity as determined by in vitro E-screen assay and in vivo uterotrophic assay.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.3
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• pp.295-301
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• 2012

This study was carried out to determine the biological activities of Wa-song (Orostachys japonicus) hot water extracts. Four types of extract samples were prepared, including Wa-song, traditional plants mixture [PM; mixture of Baekbokryung (Poria cocos), Changchul (Atractylodis rhizoma), and Sa-in (Amomum xanthoides)], and two different ratio composites of these (mixture of PM and Wa-song extract, 1:1 (v/v); PMO-1 and 1:3 (v/v); PMO-3). Their biological activities were measured using various in vitro assays. Total phenolic and flavonoid contents of PM were higher compared to those of Wa-song, and those of PMO-1 were higher than those of PMO-3. Further, PMO-1 contained higher ABTS and DPPH radical scavenging, reducing power, and nitrite scavenging activities than PMO-3. On the contrary, PMO-3 contained higher tyrosinase and inhibitory activities of MCF-7 and HT-29 cancer cells than PMO-1. According to the results, biological activities of PMOs were significantly higher than those of Wa-song extract and PM in in vitro assays. Therefore, we expect that PMOs could show higher biological activities than Wa-song extract alone in vivo.

• Korean Journal of Medicinal Crop Science
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• v.12 no.4
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• pp.304-308
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• 2004

Immune enhancing activities of water and ethanol extracts of Hypericum perforatum L. (HP) were examined. HP extracts inhibited the growth of human hepatocarcinoma, human gastric cancer cell and human breast cancer cells in concentration-dependent mammers over a concentration range of $0.05{\sim}1.0\;mg/ml$, showing inhibiton of more than 80% with the concentration of 1.0 mg/ml. However, HP the same concentration. Overall selectivity of the extracts on the three human cancer lines was over 3.5, which is higher than those from the conventional herbs. The growth of human immune B and T cells was enhanced up to 1.4 to 2.0 folds by the addition of the extracts for 4 days, compared to controls. Ethanol extracts of HP after 6 days incubation increased the secretions of tumor necrosis factor-alpha $(TNF-{\alpha})$ from T cells and interleukin-6 (IL-6) from B cells to 6.7 pg/cell and 6.8 pg/cell, respectively. These results suggest that HP has a potent immune enhancing effect.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.22-39
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• 2003

Biological activity of phenolic compounds in seeds and leaves of safflower (Carthamu tinctorius L.) were evaluated using several in vitro and in vivo assays. Six phenolic constituents were isolated from the seeds and identified as N-feruloylserotonia, N- (p-coumaroyl)serotonin, matairesinol, 8′-hydroxyarctigenin, acacetin 7-O-$\beta$-D-glucoside (tilianine) and acacetin. Six phenolic compounds exhibited considerable antioxidative activity, and especially two serotonins showed potent DPPH radical scavenging activity and antiperoxidative activity against rat liver microsomal lipid peroxidation induced by the hydroxyl radical generated via a Fenton-type reaction. Additionally, six phenolic compounds possessed comparable cytotoxicity against three cancer cells, Hela cell, MCF-7 and HepG2 cell, and particularly acacetin and its glycosides had the most potent cytotoxicity. Moreover, we found that feeding safflower seeds attenuated bone loss, and lowered levels of plasma and liver lipids in ovariectomized rats. Serotonins, lignans and flavones stimulated proliferation of the osteoblast-like cells in a dose-dependent manner (10$^{-15}$ ~10$^{-6}$ M), as potently as E$_2$ (17$\beta$-estradiol). Particularly, serotonins were mainly responsible for bone-protecting and lipid lowering effects in ovariectomized rats. Meanwhile, eight flavonoids, including a novel quercetin-7-O-(6"-O-acetyl)-$\beta$-D-glucopyranoside and seven kown flavonoids, luteolin quercetin, luteolin 7-O-$\beta$-D-glucopyranoside, luteolin-7-O-(6"-O-acetyl)-$\beta$-D-gluco-pyranoside, quercetin 7-O- -glucopyranoside, acacetin 7-O-$\beta$-D-glucuronide and apigenin-6-C-$\beta$-D-glucopyranosyl-8-C-$\beta$-D-glucopyranoside were first isolated and identified from safflower leaf. Among these flavonoids, luteolin-acetyl-glucoside and $\beta$quercetin- acetyl-glucoside showed potent antioxidative activities against 2-deoxyribose degradation and lipid peroxidation in rat liver microsomes. Luteolin, quercetin and their corresponding glycosides also exhibited strong antioxidative activity, while acacetin glucuronide and apigenin-6, 8-di-C-glucoside were relatively less active. Finally, changes in phenolic compositions were also determined by HPLC in the safflower seed and leaf during growth stages and roasting process to produce standardized supplement powerds. These results suggest that phenolic compounds in the roasted safflower seed and leaf may be useful as potential sources of therapeutic agents against several pathological disorders such as carcinogenesis, atherosclerosis and osteoporosis.

• Preventive Nutrition and Food Science
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• v.1 no.2
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• pp.220-226
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• 1996

To investigate the effect of long chain n-3 polyunsaturated fatty acids on breast cancer cell growth, estrogen-dependent MCF-7 human breast cancer cells were cultured serum-free DMEM media containing 0.5$\mu\textrm{g}$/ml of differnet kinds of fatty acids; linoleic acid(LA), arachidonic acid(AA), eicosapentaenoic acid(EPA) and docosahexaenoic acid acid(DHA) and 1, 0.1, 0.2, 0.5and 1.0ng/ml 17$\beta$-estradiol as well as 10$\mu\textrm{g}$/mi insulin and 1.25 mg/ml delipidized bovine serum albumin for 3 days. Cell growth monitored by MTT assay was lower in DHA and EPA treatments as compared to LA treatment, but not with AA treatment. Estrogen concentrations at which cell growth was initially stimulated were 0.1ng/ml for LA and DHA treatments and 0.2ng/ml for EPA and AA treatments, but the degree of stimulation was 25~30% lower in DHA and EPA treatments than in LA treatment. Fatty acid analysis showed that each fatty acid in culture medium was well incoporated into celluar lipid. Protein kinase C activity of cells was most elevated in LA treatment from 2 to 8 hours of culture followed by DHA, EPA, and AA treatments. It is concluded that inhibitions of n-3 DHA and EPA on breast cancer cell growth as compard with n-6 LA is mediated via changes in membrane fatty acid composition reducing estrogen sensitivity and increasing protein kinase C activity.

• BMB Reports
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• v.45 no.3
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• pp.159-164
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• 2012

CD99 is known to be involved in the regulation of cell-cell adhesion. However, it remains unclear whether CD99 controls cell-extracellular matrix adhesion. In this study, the effects of CD99 activation on cell-extracellular matrix adhesion were investigated. It was found that engagement of CD99 with the stimulating antibody YG32 downregulated the adhesion of MCF-7 cells to fibronectin, laminin and collagen IV in a dose-dependent manner. The CD99 effect on cell-ECM adhesion was inhibited by overexpression of the dominant negative form of CD99 or CD99 siRNA transfection. Treatment of cells with $Mn^{2+}$ or by ${\beta}_1$ integrin-stimulating antibody restored the inhibitory effect of CD99 on cell-ECM adhesion. Cross-linking CD99 inactivated ${\beta}_1$ integrin through conformational change. CD99 activation caused dephosphorylation at Tyr-397 in FAK, which was restored by the ${\beta}_1$ stimulating antibody. Taken together, these results provide the first evidence that CD99 inhibits cell-extracellular matrix adhesion by suppressing ${\beta}_1$ integrin affinity.