RRM2 associates with RRM1 to form an active RR and its accumulation plays a central role in controlling RR activity.27 RRM2 is known to play an active role in tumorigenesis28 and is a prognostic factor for cancers such as colon, breast and pancreas.29–31 These data suggest that these three genes may be involved in ACC pathogenesis and aggressiveness. Here, RRM2 is linked to adrenal cortex carcinoma.