Inactivation of the Arf-Mdm2-p53 tumor suppressor pathway is a necessary event for tumorigenesis. Arf controls Mdm2. which in turn regulates p53. but Arf and Mdm2 also have p53-independent functions that affect tumor development. https://www.spidertattooz.com/Essie-Garden-Variety-0-5-oz-904-p15641/