*2.1. Materials*

PFD was purchased from Tokyo Chemical Industry Co., Ltd. (Tokyo, Japan). Rabbit monoclonal anti-p21 and anti-CDK2 antibodies were purchased from Cell Signaling Technology (Danvers, MA, USA). Rabbit polyclonal anti-phospho-Akt (Ser473) and anti-Akt antibodies were purchased from Cell Signaling Technology. Mouse monoclonal anti-β-actin (clone AC-15) antibody was purchased from Sigma-Aldrich Co. (St. Louis, MO, USA). Rabbit polyclonal anti-PSA antibody was purchased from Dako Cytomation (Copenhagen, Denmark). Rabbit polyclonal anti-AR (N-20) antibody was purchased from Santa Cruz Biotechnology (Santa Cruz, CA, USA).
