TP53 and cancer: In particular, miRNAs targeting the TP53 mRNA were previously established as putative gatekeepers that prevent p53 hyperactivation and some of these miRNAs are also elevated in cancer, e.g. miR-504, miR-30d, and miR-125 (Hu et al., 2010; Li et al., 2012; Banzhaf-Strathmann and Edbauer, 2014).