Restoration of p53 function in melanoma, often expressing inactivated wildtype p53, and in other tumors can be archived by targeting its antagonists, E3 ligase Mdm2, Mdm4, Mdmx, and inhibitors of apoptosis stimulating protein of p53 (iASPPs) [31] or through direct p53 activators [32]. This evidence concerns the gene MDM4 and melanoma.