Indeed, numerous studies have reported that p53 directly downregulates the expression of key positive regulators of cancer in the p53 pathway, such as CD44 (ref. 63) and PCNA64,65, as well as the oncoproteins c-Myc52,66, E2F67,68, and mTORC169–71 (Supplementary Fig. 19). Here, TP53 is linked to cancer.