Importantly, microRNAs post‐transcriptionally regulate the ubiquitin‐proteasome system and it has been demonstrated that miR 221 targeting E3 ubiquitin‐protein ligase homologue (MDM2) is able to modulate p53 (TP53) in hepatocellular carcinoma.3 This evidence concerns the gene TP53 and hepatocellular carcinoma.