title: Genistein-induced G2/M cell cycle arrest of human intestinal colon cancer Caco-2 cells is associated with Cyclin B1 and Chk2 down-regulation.
abstract: Genistein is an isoflavonic phyto-oestrogen contained in soya beans. It is thought to display anti-cancer effects. This study was designed to investigate its effect on human intestinal colon cancer Caco-2 cells. MTT assay, flow cytometric analysis and western blotting were used to investigate the effect of genistein on cell proliferation, cell cycle progression and protein alterations of selected cell cycle-related proteins in Caco-2 cells. Our results showed that genistein and daidzein significantly suppressed cell proliferation. Genistein treatment was demonstrated to modulate cell cycle distribution through accumulation of cells at G2/M phase, with a significant decreasing effect of Cyclin B1 and Serine/threonine-protein kinase 2 (Chk2) proteins expression. However, daidzein did not alter the cell cycle progression in Caco-2 cells. All these observation strongly indicate that genistein has anti-proliferative effect in human intestinal colon cancer Caco-2 cells through the down-regulation of cell cycle check point proteins, Cyclin B1 and Chk2.
authors.affiliation: Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572, Japan, han.junkyu.gn@u.tsukuba.ac.jp.
authors.forename: Junkyu
authors.initials: J
authors.lastname: Han
authors.forename: Yui
authors.initials: Y
authors.lastname: Kurita
authors.forename: Hiroko
authors.initials: H
authors.lastname: Isoda