Buforin IIb induces androgen-independent prostate cancer cells apoptosis though p53 pathway in vitro

Prostate cancer (PCa) is one of the most common male cancer types, androgen-independent prostate cancer possesses poor prognosis. Buforin IIb, an attractive antibacterial peptide derived from histone H2A, showed selective cytotoxicity against most cancer cell lines. However, the molecular mechanism of buforin IIb on prostate cancer cell has still not been determined. In this study, we found buforin lIb significantly inhibited the prostate cancer cells proliferation, Furthermore, buforin IIb-induced cell apoptosis through downregulation of pro-caspase 3/8/9, poly (ADP-ribose) polymerase PARP and anti-apoptotic Bcl-2 and upregulation of proapoptotic Bax. In addition, buforin IIb increased the expression of tumor suppressor p53 and its target genes p21, fas, noxa and puma. The cytotoxicity of buforin IIb on PC-3 and Du-145 cells is decreased by p53 knockdown. In conclusion, our results indicated that buforin IIb induced PC-3 and Du-145 cell apoptosis and could be considered as a potential drug for prostate cancer.