CDK1 and prostate cancer: ISL induces cell apoptosis in prostate cancer cells through G2/M cell cycle arrest with concomitant downregulation of cyclin B1, CDK1 (p-Thr14, p-Tyr15, and p-Thr161) (after 48 h of treatment, the IC50 of ISL on PC-3 and 22RV1 is 19.6 and 36.6 μM, respectively) [114].