TP53 and neoplasm: Mouse double minute 2/X homologs (MDM2/MDMX) are the primary negative regulators of the p53 tumour suppressor.1 The p53 suppressor plays a critical role in protecting cells from malignant transformation by inducing cell-cycle arrest and apoptosis in response to DNA damage and cellular stress.1 MDM2/MDMX forms a protein–protein interaction (PPI) with the transactivation domain of p53, resulting in a complex allowing identification of this protein for degradation.2,3 Specifically, wild-type (WT) p53 features an N-terminal α-helical portion that interacts with MDM2/MDMX.