It has been demonstrated that after the application of different chemotherapeutic agents (cisplatin, camptothecin, etoposide, paclitaxel and vindesine), up to 10% of the tumour cells enter a non-proliferative state reversible upon the overexpression of cyclin-dependent kinase Cdc2/Cdk1 [111]. The gene discussed is CDK1; the disease is neoplasm.