Identification and interaction analysis of key genes and microRNAs in atopic dermatitis by bioinformatics analysis

Summary Background Atopic dermatitis (AD) is a skin disease that carries a major health burden, but the exact mechanism of the disease is not yet known. Aim To identify the key genes and micro (mi)RNAs in AD, and to explore their potential molecular mechanisms. Methods From the Gene Expression Omnibus (GEO) database, we downloaded microarray data for GSE32924 (mRNA profile) and GSE31408 (miRNA profile), which were analysed using GEO2R. Functional and pathway enrichment analyses were performed using the DAVID database, and the protein–protein interaction network was constructed with Cytoscape software. In addition, targets of differentially expressed miRNAs (DEMs) were predicted by the online resource miRDB. Results In total, 328 differentially expressed genes (DEGs) were identified, including 121 upregulated and 207 downregulated genes. Gene Ontology analyses showed that upregulated genes were significantly enriched in immune responses, while downregulated genes were mainly involved in epidermis development. In addition, we identified three DEMs, all of which were downregulated. Hsa‐let‐7a‐5p may target CCR7, and hsa‐miR‐26a‐5p probably targets HAS3. Conclusions We identified lists of DEGs and DEMs in AD. Bioinformatics and interaction analysis may provide new clues for further studies of AD.