Sun C, et al. - The researchers carried out a systematic review and meta-analysis to study the clinical value of microRNAs (miRNAs) in human cholangiocarcinoma (CCA) both for all available miRNAs and single miRNA. In this meta-analysis, 34 studies including 12 diagnostic studies and 22 prognostic studies were eligible for inclusion. The findings from the present study suggested that miRNAs might provide a new approach for clinical application. For diagnosis and prognosis of CCA, miR-21 could be a promising biomarker, since it predicts shorter OS in CCA patients.