The role of WEE1 as a gatekeeper for the G2/M transition suggests that it acts as a tumor suppressor gene; however, WEE1 was overexpressed in patients with hepatocellular carcinoma, medulloblastoma, and glioma, and its levels were further elevated after exposure to chemotherapy in patients with ovarian cancer [239,240,241,242]. The gene discussed is WEE1; the disease is ovarian cancer.