MicroRNAs in hepatocellular carcinoma – therapeutics and beyond: A systematic review

Hepatocellular carcinoma (HCC) causes major cancer-related deaths worldwide. The current therapeutic strategies pitted against early HCC are woefully inadequate with surgical interventions, radiation therapy, and chemotherapy to suffice for. Therefore, the quest for novel, effective, and decisive screening tools is paramount. In context, microRNAs (miRNAs) have emerged as useful biomarkers in HCC. Accordingly, PubMed, Medline, Embase, and Cochrane databases were explored for relevant literature in English with combination of keywords “microRNA and hepatocellular carcinoma,” “microRNA and diagnosis and hepatocellular carcinoma,” “microRNA and prognosis and hepatocellular carcinoma,” “microRNA and survival and hepatocellular carcinoma,” and “microRNA and therapy and hepatocellular carcinoma” that were extracted till January 2017. Manuscripts relating to long noncoding RNAs and other concomitant small molecules involved in HCC were excluded from the review. Studies revealed a plethora of miRNAs and their altered expression profiles being significantly implicated in the diagnosis, prognosis, recurrence, and overall survival in HCC. Several miRNAs are currently being tested in different phases of clinical trials. Efforts should aim at a better validation and establishment of miRNAs as powerful diagnostic and prognostic investigating aid for HCC. However, despite extensive research, a consensus on the universal set of miRNAs to be used as diagnostic, prognostic, or recurrence markers for HCC is yet to be achieved. In addition, various targeted approaches should focus to reduce the possibility of deleterious off-target effects of miRNAs. On this background, this systematic review discusses latest developments on miRNAs as a marker of diagnosis, prognosis, recurrence, overall survival as well as a therapeutic target in HCC (REVIEW registry216).