PTEN and neoplasm: PTEN (phosphatase and tensin homolog) is a tumor suppressor that dephosphorylates PIP3 and negatively regulates the phosphoinositide 3-kinase (PI3K) pathway [8] that, when lost, leads to constitutive activation of PI3K, which acts downstream to activate protein kinase B (AKT) and mTOR (mammalian target of rapamycin) signaling [8,38] pathways that are involved in the regulation of cell growth, survival, and proliferation [39] and protein synthesis [38], respectively.