The literature and NCBI Gene Expression Omnibus (GEO) databases were used to identify HCC-related miRNAs. Based on the rankings of a vote-strategy method, the most constantly stated dysregulated miRNAs were chosen as predictive biomarkers for HCC patients’ survival. Eligible studies were searched and sufficient data were collected for metaanalysis on prognosis. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were used to estimate the effect size. The top six upregulated and six downregulated miRNAs were identified based on 43 published miRNA profiling studies. 30 additional studies involving 2735 HCC patients with follow-up data were also included. Among the top 12 dysregulated miRNAs, miR-222, miR-25, miR-221, miR-21, miR-214, miR-199a-3p and miR-199a-5p were found to be closely associated with HCC patients’ survival. Both univariate and multivariate results suggested that the low quality of life for HCC patients was significantly related with high miR-21, miR-221, miR-25 and low miR-199a-3p, miR-214.
Based on this evidence, researchers conclude that miR-222, miR-221, miR-21 and miR-25 are significantly related with dismal prognosis for HCC patients, and miR-199a-3p and miR-214 emerged as significant predictors of unfavorable prognosis for HCC patients. These miRNAs may serve as potential candidates for HCC prognosis and therapy.