Induction of G2/M cell cycle arrest and apoptosis by cotreatment with selenite and genistein in LNCaP and PC3 cells. A and B: The MTT assay of cell viability of LNCaP cells and PC3 cells treated with selenite (Sel), genistein (Gen), or in combination for 5 days. C and D: Flow cytometry analysis of the G2/M population in LNCaP cells and PC3 cells treated with selenite, genistein, or in combination for 24 h. E and F: Flow cytometric analysis of Annexin V-positive apoptotic cell population in LNCaP cells and PC3 cells treated with selenite, genistein, or in combination for 48 h. Data were obtained from 3 independent experiments and the results shown are mean ± SD. Means with different letters above bars indicate significant differences (P < 0.05) in each panel. DMSO, dimethyl sulfoxide.