As far as the interaction between P53 and MDM2/MDMX is concern, several reports suggest that MDM2 antagonists might not be effective in tumors overexpressing MDMX, highlighting the potential of a concomitant and simultaneous targeting of the two oncosuppressor that have led to the development of “dual inhibitors” of MDM2 and MDMX for cancer therapy [123, 124]. This evidence concerns the gene MDM2 and cancer.