MDM2 and cancer: While factors that mediate transcriptional regulation at the P1 promoter on MDM2 still remain underexplored, it has been reported that oncoproteins such as the N-myc proto-oncogene (MYCN) can regulate MDM2 transcription through the P2 promoter leading to the overexpression of MDM2 in cancers such as neuroblastoma [10,13,14].