Here, we found that a RAB3IP-derived circRNA, termed circRAB3IP, is highly expressed in EnzR PCa cells and that increased circRAB3IP may decrease Enz sensitivity by acting as a competing endogenous RNA (ceRNA) for miR-133a-3p/miR-133b to regulate serum and glucocorticoid-regulated kinase 1 (SGK1) expression. Here, SGK1 is linked to posterior cortical atrophy.