microRNAs in liver disease: from diagnostics to therapeutics.

There is a need to identify effective biomarkers for diagnosis, prognosis and prediction of treatment efficacy for many liver diseases such as hepatocellular cancer, and chronic viral hepatitis. The identification of disease-specific alterations in microRNA expression and the ability to detect microRNAs in the circulation provide the basis for identifying novel clinically effective treatments and biomarkers. Knowledge regarding miRNA in human liver disease may eventually lead to serum or tissue biomarkers with clinical utility. A selection of relevant studies is reviewed. There are major challenges that need to be addressed prior to clinical application such as the need for careful validation of diagnostic miRNA candidates in well described clinical cohorts, and technical issues such as quantitation and standardization of assays. The rapid progress in therapeutic interventions using miRNA based strategies for chronic hepatitis C and hepatocellular cancer provides optimism for novel approaches that will build on the existing and emerging knowledge regarding miRNA in liver diseases.