Phosphatase and tensin homolog (PTEN) is a tumor suppressor that dephosphorylates the second messenger phosphatidylinositol 3, 4, 5-triphosphate, inhibits the PI3K/AKT pathway and reduces cyclin D1 accumulation, inducing cell cycle arrest at the G0/G1 phase. This evidence concerns the gene PTEN and neoplasm.