KCNJ5 and neoplasm: CYP11B2 is specifically expressed in ZG, and 17α-hydroxylase/17,20-lyase (CYP17A1) is expressed in ZF and ZR in the normal adult adrenal gland; however, APA with a KCNJ5 mutation typically has predominant clear cells (ZF-like cells) [59], and expression of both CYP11B2 and CYP17A1 is found within the same tumor [60,61].