International Journal of General Medicine (Jun 2023)
Identification and Validation of Hub Immune-Related Genes in Non-Alcoholic Fatty Liver Disease
Abstract
Juyi Li,1,2 Chunjia Kou,1 Tiantian Sun,3 Jia Liu,3– 5 Haiqing Zhang1,3– 5 1Department of Endocrinology, Shandong Provincial Hospital, Shandong University, Jinan, Shandong, 250021, People’s Republic of China; 2Department of Endocrinology, Geriatrics Center, The First Affiliated Hospital of Anhui University of Chinese Medicine, Hefei, Anhui, 230001, People’s Republic of China; 3Department of Endocrinology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, 250021, People’s Republic of China; 4Shandong Clinical Medical Center of Endocrinology and Metabolism, Jinan, Shandong, People’s Republic of China; 5Institute of Endocrinology and Metabolism, Shandong Academy of Clinical Medicine, Jinan, Shandong, People’s Republic of ChinaCorrespondence: Jia Liu, No. 324, Five-Jing Road, Jinan, Shandong Province, China, Email [email protected] Haiqing Zhang, No. 324, Five-Jing Road, Jinan, Shandong Province, China, Email [email protected]: Nonalcoholic fatty liver disease (NAFLD) is the most common progressive liver disease worldwide. It can cause liver cancer and possibly death. Abnormal immune infiltration is involved in the progression of NAFLD. The aim of this study was to identify and validate the hub immune-related genes in NAFLD.Methods: Microarray data were downloaded from Gene Expression Omnibus, and immune-related differentially expressed genes (IRDEGs) were obtained. A protein–protein interaction network was used to further screen. The diagnostic value of the IRDEGs was evaluated by receiver operating characteristic curves. Differences in immune infiltration levels were analyzed using single-sample gene set enrichment analysis. Hub IRDEGs were identified by correlation analysis with immune infiltration levels. Finally, molecular experiments were used to confirm the expression of the hub IRDEGs and explore their roles in NAFLD.Results: We obtained 18 IRDEGs. Five hub genes were further identified by protein–protein interaction network, receiver operating characteristic curves and correlation analysis: AQP9, BACH2, CD4, IL17RE and S100A9. Based on functional enrichment analysis, the hub genes were enriched primarily in many immune-related pathways. In NAFLD, AQP9, CD4, and IL17RE expression was significantly reduced, whereas BACH2 and S100A9 expression was elevated. PCR, oil red O staining and triglyceride detection revealed that the knock-down of BACH2 and S100A9 reduced lipid accumulation in NAFLD cells.Conclusion: This study provided insight into the profile of immune infiltration underlying NAFLD and identified AQP9, BACH2, CD4, IL17RE and S100A9 as ancillary diagnostic indicators of NAFLD. And BACH2 and S100A9 might be therapeutic targets for NAFLD.Keywords: nonalcoholic fatty liver disease, immune infiltration, BTB domain and CNC homolog 2, BACH2, S100 calcium binding protein A9, S100A9
