LncRNA FGF7-5 and lncRNA GLRX3 together inhibits the formation of carotid plaque via regulating the miR-2681-5p/ERCC4 axis in atherosclerosis.

Atherosclerotic plaques belong to the common vascular disease in the aged, which rupture will lead to acute thromboembolic diseases, the leading cause of fatal cardiovascular events. Accumulating evidence indicates that the lncRNAs-miRNAs-mRNA regulatory network plays a critical role in atherosclerosis. Based on RNA sequencing (GSE207252), we constructed expression profiles of lncRNAs, microRNAs, and mRNA in the carotid plaque of atherosclerosis patients and analyzed differentially expressed genes (DEGs). We identified three candidate lncRNAs using two algorithms (LASSO and SVM-RFE): lnc_GLRX3, lnc_FGF7-5, and DISC1FP1). LNCipedia, TargetScan, and miRDB databases were used to predict target miRNAs of lncRNAs and target genes of miRNAs. Gene ontology (GO) functional annotation, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, and Gene Set Enrichment Analysis (GSEA) analysis of DEGs was carried out using the R package clusterProfiler. A PPI network was constructed using the STRING website and visualized by Cytoscape. According to the "MCC" method of the plug-in cytoHubba in Cytoscape, ERCC4 was the top hub gene of the PPI network. We constructed a lncRNA_FGF7-5/lncRNA_GLRX3-miR-2681-5p-ERCC4 regulatory network for carotid plaque using lncRNA-miRNA and miRNA-mRNA pairs. Next, lncRNA_FGF7-5 and lncRNA_GLRX3 targeted miR-2681-5p directly to upregulate ERCC4 expression. Silencing of lncRNA_FGF7-5 and lncRNA_GLRX3 promoted apoptosis and TP53 expression in HUVECs treated with ox-LDL; however, these effects were reversed by ERCC4-overexpression. Taken together, these findings indicated that lncRNA_FGF7-5 and lncRNA_GLRX3 together reduced atherosclerosis-induced apoptosis of HUVECs via targeting miR-2681-5p to increase ERCC4 expression, thereby preventing the formation of carotid plaque and finally inhibiting atherosclerosis progression.