TP53 and cancer: Accordingly, miRNAs of the let‐7 family are downregulated in various types of cancer (Johnson et al, 2005; Roush & Slack, 2008) and several regulate p53 signaling, cell proliferation, and/or tumorigenicity (Yu et al, 2007; Suh et al, 2012; Wang et al, 2012; Li et al, 2014; Subramanian et al, 2015).