Coordinated Transcriptional Repression of CAV1 and CAV2 in Thoracic Aortic Aneurysm: A microRNA Regulatory Network...

Background: Thoracic aortic aneurysm (TAA) is a potentially life-threatening degenerative disease whose principal danger arises from progressive aortic dilation with the attendant risk of rupture and dissection and which is characterized by extracellular matrix breakdown, smooth muscle loss, and endothelial dysfunction. Caveolae, plasma membrane microdomains built from caveolins (CAV1-3) and cavins (CAVIN1-4), govern nitric oxide (NO) signaling, endocytosis, and mechanotransduction. We hypothesized that downregulation of caveolae-associated genes, driven in part by microRNAs, contributes to endothelial failure and vascular remodeling in TAA. Methods: Normalized transcriptomic expression values for five caveolae-associated genes were retrieved from the GSE26155 dataset (43 TAA and 43 control aortas) using GEO2R. Differential expression was assessed for CAV1, CAV2, CAV3, CAVIN1, and CAVIN2, and Spearman correlation with Deming regression explored inter-gene relationships. Functional enrichment (Enrichr) and experimentally validated microRNA-target interactions (miRTarBase) were used to infer regulatory and mechanistic networks. CpG island mapping and gene-gene interactome construction (GeneMANIA) complemented the analyses. Results: CAV1 and CAV2 were downregulated in TAA at nominal significance (CAV1, p = 0.0225; CAV2, p = 0.0361); after Benjamini-Hochberg correction across the five candidate genes both differences attenuated to a consistent trend (q approximately 0.09), while the two caveolins were strongly co-expressed (Spearman r = 0.527, p < 0.001; Deming CAV2 = 1.881 × CAV1-0.892), indicating coordinated transcriptional regulation. Network analysis linked both genes to NOS3, NOSTRIN, EGFR, HRAS, and RAC1, consistent with impaired endothelial nitric oxide and GTPase signaling. Gene Ontology enrichment highlighted endothelial proliferation, nitric oxide metabolism, calcium homeostasis, vesicle organization, and MAPK regulation. Database-supported analysis (miRTarBase) identified miR-93-5p, miR-199a-3p, miR-203a-3p, and the miR-29 family as experimentally validated candidate repressors of CAV1/CAV2. Conclusions: This integrative transcriptomic and microRNA analysis identifies coordinated CAV1 and CAV2 downregulation as a candidate molecular event in thoracic aortic aneurysm, associated with caveolar loss, endothelial dysfunction, and disrupted nitric oxide homeostasis. The CAV1/CAV2-microRNA axis represents a candidate mechanistic signature warranting further investigation as a potential therapeutic target in aortic disease.