Studies on the mechanism of Deguelin-induced apoptosis of human prostate cancer cell lines

Objective To investigate the anticancer effects and molecular mechanism of deguelin on human prostate cancer cells PC3 and DU145 in vitro. Methods Cells were treated with either 0.1% DMSO as diluent control,wortmannin 100 nmol/L as positive control or various concentrations of deguelin ( 10 nmol/L, 100 nmol/L and 1 μmol/L). CCK-8 assay was used to identify the inhibitory effect of Deguelin on proliferation in PC3 and DU145 cells. Apoptosis was assessed through annexin V/PI donhle-labeled cytometry. The effect of deguelin on the cell cycle of PC3 and DU145 cells was studied by propidium iodide method. Western blot assay was used to detect the expression of AKT, p42/44 MAPK and their phosphorylated proteins. Results Deguelin 10 nmol/L -1 μmol/L could inhibit the proliferation of PC3 cells hut had little effect on DU145 cells. Deguelin significantly increased the percentage of G2/M phase and induced apoptosis of PC3 cells,but didn' t alter cell cycle and induce apoptosis of DU145 cells. The expression of pAKT protein was decreased in PC3 ceils treated with Deguelin hut not in DU145 cells. Conclusion Deguelin can inhibit cell growth,induce G2/M arrest and apoptosis of PC3 cells by blocking PI3K/AKT path way but has little effect on DU145 ceils. The different effects of Deguelin on PC3 and DU145 cells are caused by the different activated status of PI3K/AKT pathway between the two ceils.