Our experiments showed that CDK4, CDK6, CDK2, cyclinD1 and phosphorylated Rb were downregulated, while p27 and p15 were increased, by inhibiting USP14 expression or its activity in androgen-responsive prostate cancer cells; and conversely, the exactly opposite changes were induced by USP14 overexpression. Here, CDK4 is linked to Familial prostate cancer.