Loss of wild-type p53 function through mutations of the p53 gene and other mechanisms such as overexpression of negative regulators of p53 (e.g. MDM2, MDM4, and PPM1D) has been known as a prerequisite for initiation and/or progression of many human cancers (Levine et al., 2006; Muller and Vousden, 2013; Donehower et al., 2019; Levine, 2019). This evidence concerns the gene MDM2 and cancer.