Objective:To study the treatment effects of androgen receptor(AR)antagonist combined with class I histone deacetylase(HDAC)inhibitors on prostate tumorosphere,and to investigate the possible molecular mechanisms involved in the process. Methods:Prostate cancer LNCaP and 22RV1 cells were cultured in serum-free suspension condition,and the obtained two tumorosphere stem-like cells were treated with AR antagonist MDV3100 with or without the presence of HDAC class I inhibitor MS-275 to study the morphology change and the ability of cell clone formation in monolayer culture condition. Then,quantitative real-time fluorescence polymerase chain reaction(qRT-PCR)was utilized to analyze cancer stem cell marker CD133 expression,and Western blot was used to detect the levels of DNA damage marker H2A.X(p-H2A.X),the cleavage of poly ADP-ribose polymerase(PARP),β-catenin,proto-oncogene c-Myc and cyclin D1. Results:Treatment with MDV3100 alone inhibited CD133 expression in tumorosphere cells. Combination treatment of MDV3100 with MS-275 reduced the number of tumorosphere,inhibited CD133 transcription,enhanced the level of both PARP cleavage and p-H2A.X,decreased expression of β-catenin,c-Myc and cyclin D1. Conclusion:Compared with the treatment of MDV3100 alone,combination treatment of MDV3100 with MS-275 significantly inhibited cancer stem-like tumorosphere cell formation and promoted apoptotic cell death. The drugs-reduced over activation of Wnt/β-catenin/c-Myc/cyclin D1 pathway was possibly involved in the antitumor process. These results provide guidance for clinical application of MDV3100 and MS-275 in prostate cancer management of personal medicine.