Downregulation of miR-136-5p in hepatocellular carcinoma and its clinicopathological significance

The clinical significance of microRNA (miR)-136-5p in hepatocellular carcinoma (HCC) has not been verified. Therefore, in the current study, the authors aimed to explore miR-136-5p expression and its clinical significance in HCC, as well as to investigate its potential target genes function. The authors detected the levels of miR-136-5p in 101 pairs of HCC and para-cancer tissues via reverse transcription-quantitative polymerase chain reaction. Gene Expression Omnibus database and the Cancer Genome Atlas (TCGA) database were used to further verify the clinical significance of miR-136-5p expression in HCC. The target genes prediction analysis of miR-136-5p, natural language processing (NLP) analysis of HCC in PubMed and gene functional enrichment analysis were conducted. The miR-136-5p level was markedly downregulated in HCC tissue, compared to para-non-tumor tissue. MiR-136-5p expression decreased in HCC patients with metastasis (P=0.004), advance TNM stage (P<0.001), portal vein tumor embolus (P=0.007) and vaso-invasion (P=0.003), compared with those HCC patients with non-metastasis, early TNM stage, non-portal vein tumor embolus and non-vaso-invasion, respectively. In the TCGA database, downregulated miR-136-5p was also observed in HCC tissue compared to normal liver tissue (P<0.001). There were 178 genes obtained from the overlap between predicted targets and NLP analysis. GO and KEGG pathway analyses revealed some significant pathways related to cancers. Downregulation of miR-136-5p may be responsible for the carcinogenesis and aggressiveness of HCC. miR-136-5p may act as an anti-carcinoma miRNA, which is essential for HCC progression through the regulation of various signaling pathways. Thus, miR-136-5p interaction may provide a novel strategy for HCC treatment.