Key Genes and Biological Pathways in Pulmonary Arterial Hypertension Related to Endoplasmic Reticulum Stress Identified by Bioinformatics.

Abstract: Pulmonary arterial hypertension (PAH) is a cardiopulmonary vascular condition with an unclear pathogenesis. Targeting endoplasmic reticulum (ER) stress has been suggested as a novel treatment approach for PAH, but the mechanisms involving ER stress-related genes in PAH are not well understood. Microarray data for PAH and ER stress-related genes were analyzed. Differential and Venn analyses identified 17 differentially expressed ER stress-related genes in PAH. Candidate drugs targeting these genes were predicted using the CMap database. A protein-protein interaction (PPI) network was constructed, and hub genes (LCN2, IGF1, VCAM1, EDN1, HMOX1, TLR4) with complex interplays were identified using the STRING database and Cytoscape plugins. The clinical diagnostic performance of the hub genes was evaluated using ROC curves. The GeneMANIA Web site was utilized to predict enriched pathways associated with the hub genes and their functionally similar genes. MiRNAs and transcription factors targeting the hub genes were predicted using the Networkanalyst Web site. The immune levels in control samples and PAH samples were assessed using various algorithms. Nine drug candidates were found to potentially target the identified ER stress-related genes. The hub genes and their correlated genes were significantly enriched in immune-related pathways. The PAH group showed increased immune cell infiltration, indicating a heightened immune response. This study sheds light on the role of ER stress-associated hub genes in PAH and proposes potential drugs targeting these genes. These findings provide valuable insights into PAH mechanisms and support the exploration of ER stress as a therapeutic target.