Integrated analysis of clinical significance and functional involvement of microRNAs in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common lethal cancers worldwide. To explore the potential prognosis-associated microRNAs (miRNAs) for HCC patients, we performed integrated analyses on the miRNA expression profiles from The Cancer Genome Atlas project. Genome-wide overall survival (OS)- and progression-free survival (PFS)-associated miRNA screening were performed by multivariate Cox proportional hazards regression analyses. A five-miRNA expression signature (miR-148a, miR-3677-3p, miR-744*, miR-210, and miR-3613-5p) was identified as an indicator for HCC OS (p < .0001; hazard ratio [HR] = 2.631). In addition, a seven-miRNA expression signature (miR-127-5p, miR-146a, miR-152, miR-193a-3p, miR-331-5p, miR-500a*, and miR-550a*) was identified as a predictor for HCC PFS (p < .0001; HR = 2.608). This systematic analysis suggested that both the OS- and PFS-associated signatures have better performance in HCC survival prediction than the conventional clinicopathological parameters. Further functional enrichment analysis of the corresponding genes targeted by these signature miRNAs revealed their biological significance in the PI3K-Akt signaling pathway. In conclusion, our present study identified a five-miRNA OS-associated signature and a seven-miRNA PFS-associated signature as HCC prognostic biomarkers with potential clinical significance, which could enable the development of novel targeted therapeutic strategies for HCC treatment.