PIK3CA encodes p110α, an isoform of the 110-kDa catalytic subunit of the class 1A phosphatidylinositol-3-kinase (PI3K). The PI3K−Akt−mTOR pathway is one of the most frequently hyperactivated signaling cascades in tumor cells. Enhanced Akt signaling induces a Warburg phenotype and increases the coupling of glycolysis to the mitochondrial citric acid cycle which yields intermediates for biosynthetic pathways and NADH as the primary electron donor for OXPHOS (reviewed in50). The gene discussed is PIK3CA; the disease is neoplasm.