Mutations in multiple genes encoding tumor suppressor proteins that inhibit cell growth and proliferation have been identified in endometrial cancer cells, such as TP53 (deletion) and PTEN (missense mutation) in RL95-2 cells and TP53 (missense mutation) and KRAS (missense mutation) in HEC-1-A cell [18]. The gene discussed is PTEN; the disease is endometrial cancer.