CDK4 and neoplasm: These data suggest that safranal potentially suppresses Pca recurrence in vivo, reduces Skp2, E2F1, NF-κB p65, p-IκBα (Ser32), c-MYC, p-Rb (Ser807), CDK4, CDK6, and CDK2, and elevates p21 and p27 in safranal-treated tumor tissues.