It is known that for both human lung adenocarcinoma [38] and colon cancer [39], the elevated expression of active cyclin A-CDK2 complexes with associated higher CDK2 kinase activity is critical in the promotion of cell cycle progression and the unrestrained proliferation of tumor cells, thereby being a predictive marker for patients’ prognosis. The gene discussed is CDK2; the disease is malignant colon neoplasm.