CDKN1A and prostate carcinoma: Cell cycle arrest at the G1 phase is caused by reducing the binding of cyclin E to cdk2 and increasing the binding of cyclin D1 to WAF1/p21 and KIP1/p27, which inactivates the cyclin‐cdk complexes active in the G0/G1 phase of the cell cycle and induces apoptosis in human prostate carcinoma cells [51].