Knockdown of CDK5 in TP53 wild type ovarian cancer cells results in increased levels of TP53 with consequent transcriptional induction of p21Cip1 and a post-translational increase of p27Kip1 that arrests cancer cells in G1 and induces apoptosis that is further enhanced by treatment with paclitaxel. The gene discussed is CDKN1A; the disease is cancer.