PTEN and prostate neoplasm: Signaling through the PI3K/Akt phosphorylation cascade has been demonstrated to be a frequent event in prostate tumors that harbor the inactivated lipid phosphatase tumor suppressor gene PTEN. It has been indicated that increased signaling through the PI3K/Akt signaling pathway, as a consequence of the loss of functional PTEN, is able to drive tumor progression.