Bioinformatics-Based Characterization of Key Biomarkers and Immune Infiltration in Coronary Artery Disease

Abstract Objective: This paper aims to identify potentially related genes of coronary artery disease (CAD) and determine the relationship with immune cell infiltration.Materials and methods: Three datasets (GSE42148, GSE98583, GSE12288) containing coronary heart disease and healthy people are downloaded from the Gene Expression Database (GEO). Use the "limma" package in the "R" software to screen the differentially expressed genes (DEGs) in the three sets of data respectively, use the "pheatmap" package to construct a heatmap of the DEGs, and draw the venn maps of the three sets of differential genes. The DAVID database is used for the analysis of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG). The String platform and Cytoscape software are used to perform protein interaction analysis on differential genes, create Protein-Protein Interaction (PPI) networks on DEGs, and screen hub genes. The CIBERSORTx web version tool performs immune cell infiltration analysis on sample data sets.Results: GSE42148 screened out 227 differential genes, of which 161 were up-regulated and 66 were down-regulated (p<0.05, |logFC|>1.0); GSE98583 screened out 254 differential genes, of which 141 were up-regulated and 113 were down-regulated (p<0.05, |logFC|>1.0). 68 differential genes were screened in GSE12288, of which 33 were up-regulated and 35 were down-regulated (p<0.05, |logFC|>0.38). There are 8 differential genes in the intersection of the three groups of DEGs, namely MAP7, RIPK4, BAALC, CA6, CXCL14, HIST1H2AE, MS4A3, GPR15. With the help of enrichment analysis and the construction of PPI networks, HIST1H2AE and CXCL14 were finally determined as the key biomarkers of CAD. Immune infiltration analysis suggests that B cells naive, macrophages M0 and T cells CD4 naïve are closely related to the pathogenesis of CAD.Conclusion: HIST1H2AE and CXCL14 can be used as key biomarkers of CAD. Inflammation and immune cell infiltration play a key role in the occurrence and development of CAD.