Identification of 8-miRNAs as biomarkers for nonalcoholic fatty liver disease.

Nonalcoholic fatty liver disease (NAFLD) poses serious threats to humans. Several studies have studied the biomarkers associated with NAFLD; however, the results vary because of the differences in the sequencing platform, sample selection, and filter conditions. This study aimed to explore the key microRNAs (miRNAs) of NAFLD by a systematic bioinformatics analysis. A total of 10 qualified NAFLD miRNA data sets were selected through a literature review. Signature miRNAs were identified by overlap comparison. The target genes of miRNAs were predicted by TargetScan software and functional enrichment, and transcription factor (TF) binding analysis of target genes was carried out by the database for annotation, visualization, and integrated discovery and Tfacts database, respectively. A total of three upregulated miRNAs and five downregulated miRNAs were identified in the NAFLD tissue. The target genes of upregulated miRNAs mainly enriched in the RNA polymerase II promoter transcriptional regulation, chromatin remodeling process, and O-glycan synthesis, circadian rhythm, and endocytosis; the target genes of downregulated miRNAs mainly enriched in the transcriptional regulation of DNA as a template, negative regulation process of protein phosphorylation, and Fc epsilon RI signaling pathways, Ras signaling pathways and the interaction between cytokines and cytokines. Besides, 136 interactions were formed between 62 TFs and 45 target genes of upregulated miRNA, whereas 157 interactions were formed between 72 TFs and 45 target genes of downregulated miRNA. Both contained 102 TFs, and 32 TFs were present in both target genes. To summarize, we identified an eight-miRNA set as a signature for NAFLD, which will benefit the clinical treatment of NAFLD.