PTEN and neoplasm: The phosphatase and tensin homologue (PTEN) deleted on the chromosome 10 gene was cloned by association with the human cancer susceptibility locus at 10q23 and is a lipid phosphatase that dephosphorylates phosphatidylinositol 3,4,5-trisphosphate (PIP3) to PI(4,5)P2 and opposes the PI3K/AKT pathway, exerting tumour suppressor activity [42].