AKT1 and neoplasm: Since the discovery of protein kinase B (PKB, also known as Akt) 25 years ago [91] and the identification of phosphatidylinositol 3-kinases (PI3K) as its upstream regulator [92], PI3K/Akt acts as a central node of many signaling pathways, such as immune modulation, tumor cell proliferation, and apoptosis.