PTEN and neoplasm: Phosphatase and Tensin Homolog (PTEN) as a multifunctional tumor suppressor negatively regulates the intracellular levels of Phosphatidylinositol-3,4,5-Trisphosphate (PIP3) in the cells and negatively regulates the AKT/Protein Kinase B (AKT/PKB) signaling pathway.