MicroRNAs associated with microvascular invasion in hepatocellular carcinoma and their prognostic impacts in patients undergoing hepatic resection.

Although microvascular invasion (McVI) has prognostic value for patients with hepatocellular carcinoma (HCC) who have undergone hepatic resection, few studies have investigated the relationship between McVI and the aberrant expression of microRNAs (miRNAs). The present study identified the miRNAs that were selectively expressed in HCC with McVI and investigated their prognostic value. Clinical data and the miRNA expression profiles of 372 patients with HCC were extracted from The Cancer Genome Atlas database. miRNAs that were differentially expressed between patients with McVI and those without vascular invasion (VI) were identified and investigated as potential prognostic factors for HCC. The results demonstrated that McVI was a significant predictor of shortened recurrence-free survival (RFS). The 3 year RFS rate in patients with HCC accompanied by McVI was 28.2 and 49.3% in HCC without VI (P<0.001). miRNA-141/-582/-9 were upregulated, while miRNA-675 was downregulated in patients with McVI when compared with HCC patients without VI. Log fold-changes of miRNA-141/-582/-675/-9 were 0.80 [false discovery rate (FDR), 0.005], 0.55 (FDR, 0.045), -0.99 (FDR, 0.005) and 1.22 (FDR, <0.001), respectively. Kaplan-Meier analysis indicated that the overexpression of miR-141/-582/-9 was significantly associated with poor RFS and a poor overall survival. A text mining analysis revealed that these miRNAs were significantly associated with multifaceted hallmarks of cancer, including 'invasion and metastasis'. In conclusion, the overexpression of miRNA-141/-582/-9 was associated with McVI and a poor survival in patients undergoing hepatic resection for HCC.