PTEN and neoplasm: PTEN, a phosphatase and tensin homolog (BZS, MHAM,MMAC1, PTEN1, TEP1) is a phosphatidylinositol 3,4,5‐trisphosphate 3‐phosphatase whichacts as a tumour suppressor by reducing cellular levels of PI 3,4,5‐P, thereby toningdown activity of PDK1 and PKB.