• Journal of Life Science
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• v.20 no.4
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• pp.561-571
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• 2010

Colon cancer is one of the most common malignancies in the western world and the second leading cause of cancer death in Korea. Epidemiology studies have shown a reduced incidence of colon cancer among populations consuming a large quantity of ${\omega}3$-polyunsaturated fatty acids (${\omega}3$-PUFA) of marine origin. Recently, it has been found that ${\omega}3$-PUFA has an antineoplastic effect in several cancers. This study was designed to investigate the mechanism of the anti-invasive effect of ${\omega}3$-PUFA in colon cancer. ${\omega}3$-PUFA, docosahexaenoic acids (DHA) and eicosapentaenoic acid (EPA) treatment resulted in a dose-dependent inhibition of cell growth in SW480 human colon cancer cells. In contrast, arachidonic acid (AA), a ${\omega}6$-PUFA, exhibited no significant effect. This action likely involves apoptosis, given that DHA treatment increased apoptotic cells in TUNEL assay. Moreover, invasiveness of SW480 cells was inhibited following treatment of DHA in a dose-dependent manner; in contrast, AA had no effect. The levels of MMP-9 and MMP-2 mRNA decreased after DHA pretreatment. MMP-9 and MMP-2 promoter activities were also inhibited by DHA treatment. The levels of NF-kB and p-IkB protein were down-regulated by DHA pretreatment in a dose dependent manner. In addition, DHA inhibited NF-kB promoter reporter activities. These findings suggest that ${\omega}3$-PUFA may inhibit cancer cell invasion by inhibition of MMPs via reduction of NF-kB in colon cancer. In conclusion, ${\omega}3$-PUFA could be used for chemoprevention and treatment of human colon cancer.

• Journal of Life Science
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• v.19 no.11
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• pp.1581-1590
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• 2009

Hizikia fusiforme is a kind of brown edible seaweed that mainly grows in the temperate seaside areas of the northwest pacific, including Korea, Japan and China, and has been widely used as a health food for hundreds of years. Recently, H. fusiforme has been known to exert pharmacological activities including antioxidant, antimutagenic and anticoagulant activities. However, the molecular mechanisms of H. fusiforme in malignant cells have not been clearly elucidated yet. In this study, the effects of ethyl alcohol extract of H. fusiforme (EAHF) on the anti-proliferative effects of MDA-MB-231 and MCF-7 human breast cancer cells were investigated. EAHF treatment resulted in a concentration-dependent growth inhibition by including apoptosis in MDA-MB-231 cells and G1 phase arrest in MCF-7 cells, which could be proved by MTT assay, DAPI staining, agarose gel electrophoresis and flow cytometry analysis. In MDA-MB-231 cells, the increase in apoptosis induced by EAHF treatment correlated with up-regulation of pro-apoptotic Bax expression. EAHF treatment induced the proteolytic activation of caspase-3 and caspase-9, and a concomitant inhibition of poly (ADP-ribose) polymerase, $\beta$-catenin, phospholipase-${\gamma}1$ protein and DNA fragmentation factor 45/inhibitor of caspase-activated DNase. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of H. fusiforme.

• Journal of Life Science
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• v.20 no.7
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• pp.1054-1065
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• 2010

SH21B is a natural composition composed of seven herbs: Scutellaria baicalensis Georgi, Prunus armeniaca Maxim, Ephedra sinica Stapf, Acorus gramineus Soland, Typha orientalis Presl, Polygala tenuifolia Willd and Nelumbo nucifera Gaertner (Ratio 3:3:3:3:3:2:2). In our previous study, we reported that SH21B inhibited adipogenesis and fat accumulation in 3T3-L1 cells through modulation of various regulators in the adipogenesis pathway. The aim of this study was to analyze the transcriptome profiles for the anti-adipogenic effects of SH21B in 3T3-L1 cells. Total RNAs from SH21B-treated 3T3-L1 cells were reverse-transcribed into cDNAs and hybridized to Affymetrix Mouse Gene 1.0 ST array. From microarray analyses, we identified 2,568 genes of which expressions were changed more than two-fold by SH21B, and the clustering analyses of these genes resulted in 9 clusters. Three clusters among the 9 showed down-regulation by SH21B (cluster 4, cluster 6 and cluster 9), and two clusters showed up-regulation by SH21B (cluster 7 and cluster 8) during the adipogenesis of 3T3-L1 cells. It was found that many genes related to cell proliferation and adipogenesis were included in these clusters. Clusters 4, 6 and 9 included genes which were related with adipogenesis induction and cell cycle arrest. Clusters 7 and 8 included genes related to cell proliferation as well as adipogenesis inhibition. These results suggest that the mechanisms of the anti-adipogenic effects of SH21B may be the modulation of genes involved in cell proliferation and adipogenesis.