Identifying TF-miRNA-mRNA regulatory modules in nitidine chloride treated HCC xenograft of nude mice

Nitidine chloride (NC) has reported tumor suppressive activities for various human cancers, including hepatocellular carcinoma (HCC). Nevertheless, the pharmacological mechanism of NC on HCC has not previously been elucidated. SMMC7721 HCC cell lines, before and after the treatment of NC, were injected into nude mice for a subcutaneous tumor xenograft model. MiRNA and mRNA sequencing were performed for both control and treated xenograft tissues to further analyze differential expressed miRNAs (DEmiRNAs) and mRNAs (DEmRNAs). The ten most significant DEmiRNAs were selected for prediction of transcription factors (TFs) and target genes. We constructed an interconnected network composed of TFs the ten most significant DEmiRNAs, the 100 most significant DEmRNAs, and selected target genes from online programs. Hub genes chosen from a protein-to-protein interaction network of hub genes were validated by correlation analysis, expression analysis, and Kaplan-Meier survival analysis. The five most up-regulated miRNAs (hsa-miR-628-5p, hsa-miR-767-5p, hsa-miR-767-3p, hsa-miR-1257, and hsa-miR-33b-3p) and the five most down-regulated miRNAs (hsa-miR-378d, hsa-miR-136-5p, hsa-miR-451a, hsa-miR-144-5p, and hsa-miR-378b) were singled out from the DEmiRNAs. Functional annotations indicated that potential target genes of the top five up-regulated miRNAs were mainly clustered in molecular processes concerning epithelial-to-mesenchymal transition. Hub genes, such as ITGA6 and ITGB4, were validated as up-regulated in HCC; both IFIT2 and IFIT3 were revealed by Kaplan-Meier survival curves as good prognostic factors for HCC. In summary, the regulating axes of NC-DEmiRNAs-DEmRNAs and TFs-DEmiRNAs-DEmRNAs in HCC that were discovered in this study may shed light on the possible molecular mechanism of NC in HCC.