In normal tissue (41), INPP4B dephosphorylates both PI(3,4)P2 and PI(3,4,5)P3, but a concomitant loss of PTEN and INPP4B results in PI(3,4,5)P3 accumulation and enhanced AKT signaling, favoring tumor growth and progression (47). The gene discussed is INPP4B; the disease is neoplasm.