Potential prognostic value of hsa-miR-18a in hepatocellular carcinoma and the underlying key down-stream gene CHRM2: a comprehensive bioinformatic analysis*

Abstract Background Hepatocellular carcinoma (HCC) is still the fourth leading cause of cancer-related death. Better prognosticators are warranted for HCC. Hsa-miR-18a has been considered implicated in the pathogenesis of several tumors including HCC. Methods Bioinformatic analyses were conducted to predict target genes and carry out enrichment analysis. Validated downstream genes of hsa-miR-18a were obtained from PubMed database. Differential expression analysis was conducted within the “edgeR” R package based on the TCGA datasets. Survival analysis was performed by Kaplan-Meier survival analysis. All the visualizations were implemented by R. Results Bioinformatic analysis obtained a total of 90 target genes of hsa-miR-18a and revealed that target genes were involved in pathways essential for cancer onset and development such as cell cycle and PI3K/AKT signaling pathway. A review of literatures found target genes of miR-18a indeed participating in the biological processes of HCC. CHRM2 was identified as a special gene after the intersection analysis of TCGA differentially expressed genes (DEGs) and predicted target genes. Survival analysis validated that hsa-miR-18a and CHRM2 significantly affected the prognosis of HCC patients. Conclusion There is a strong association between hsa-miR-18a with tumors including HCC via participating essential tumor-promoting pathways including cell cycle, PI3K/AKT signaling pathway, etc. Furthermore, high miR-18a expression and low CHRM2 expression could lead to a poor prognosis in HCC. In conclusion, miR-18a could serve as an expectational prognostic biomarker in HCC.