Hepatic microRNA orchestra: a new diagnostic, prognostic and theranostic tool for hepatocarcinogenesis

MicroRNAs are evolutionary conserved single stranded non-coding RNAs with immense ability to posttranscriptionally regulate gene expression via complementary base pairing with mRNAs of more than 50% protein encoding genes. They play diverse roles in physiological and pathophysiological processes such as normal development and cancer pathogenesis respectively. Recent investigations have focused on the identification and characterization of microRNAs aberrantly expressed in cancer and their target molecules that are critically involved in the initiation, progression and development of carcinogenesis as possible diagnostic, prognostic and theranostic (Integration of biomarker use as diagnostic tools and target-specific therapies to enhance selective and individualized therapy) tools to augment conventional cancer therapeutic armamentarium. In this mini review, we bring to focus the intricate interactions between microRNAs aberrantly expressed in hepatocarcinogenesis and their interactions with the transforming growth factor beta (TGF-β)/Small mother against decapentaplegic (Smad) and the mitogen activated protein kinases (MAPKs) signaling pathways. Importantly, we highlight microRNA-Specific targets as possible biomarkers for prognosis, diagnosis and as therapeutic targets for hepatocellular carcinoma (HCC) while at the same time exploring new directions for future investigations.