Screening of Key Genes in Severe Burn Injury at Different Stages via Analyzing Gene Expression Data.

Microarray analysis was performed to investigate the changes in gene expression profiles after severe burn injury at the early and middle stages, further discovering therapeutic targets for severe burn injury. Microarray data (GSE19743) were downloaded from Gene Expression Omnibus. First, differentially expressed genes (DEGs) at different stages were screened using limma package. Gene Ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis of DEGs were then performed using DAVID. Protein-protein interaction (PPI) networks were also constructed using String database. Additionally, transcription factor binding site was detected using the Whole-Genome rVISTA. Compared with the healthy controls, 160 DEGs were identified in patients with early-stage burn injury and 261 DEGs were obtained in patients with middle-stage burn injury. Only 10 genes showed differential expression between the early and middle stages. KEGG functional analysis indicated that DEGs detected at the early stage were mainly enriched in the immune response, kinase activity, and signaling pathways and DEGs detected at the middle stage were involved in the immune response, protein and fat metabolism, and programmed cell death pathways. Three PPI networks were constructed and hub proteins with high degrees of connection were screened, such as lactotransferrin, interleukin 8, and perforin-1. Additionally, many transcription factor binding sites that may be involved in the regulation of these DEGs were also detected. A number of DEGs were identified in patients with early- and middle-stage burn injury, which helps to deepen the understanding about the molecular mechanism underlying severe burn injury.