Low expression of ESR1 correlates with ascending aortic dilation and acute type A aortic dissection.

Background: The common genetic signatures of ascending aortic dilation and acute type A aortic dissection (AAAD) remained unclear. This study aims to investigate the role of ESR1 in ascending aortic dilation and AAAD via a multi-omics approach combining transcriptome-wide association study (TWAS) and mRNA expression profiles.

Methods: The TWAS analysis was performed by integrating expression quantitative trait loci (eQTL) data of aorta and the GWAS dataset of ascending aortic diameter using the FUSION software. Joint/Conditional Analysis was used to screen conditionally independent genes from TWAS significant regions. mRNA expression profiles were used to confirm the differential expression of ESR1 in ascending aortic dilation and AAAD. An independent mRNA expression profile dataset was used to validate the diagnostic efficiency of ESR1 expression on thoracic aortic aneurysm (TAA). Gene set enrichment analysis (GSEA) was utilized to explore the potential molecular function of ESR1 in mouse aorta. Immune infiltration analysis was performed to evaluate the association between ESR1 and immune infiltration in AAAD.

Results: ESR1 was among the top 10 most significant genes identified by TWAS of ascending aortic diameter (Z score = -7.3, P = 3.30 × 10). mRNA expression profiles confirmed the low expression of ESR1 both in ascending aortic dilation (P = 0.0361) and AAAD (P = 0.0142). The diagnostic efficiency of peripheral blood ESR1 expression on TAA was further validated by an independent mRNA expression profile dataset. GSEA showed that GO terms and KEGG pathways mainly involved in metabolism and oxidoreductase activity were enriched in aortic tissue of ERα knockout mice. The immune infiltration ration of naive CD8 + T cells was significantly lower in AAAD compared with normal aorta, and was positively correlated with ESR1 expression.

Conclusion: Low expression of ESR1 is associated with ascending aortic dilation and AAAD. Peripheral blood ESR1 expression may be a novel diagnostic biomarker of TAA. ESR1 expression is positively correlated with immune infiltration ration of naive CD8 + T cells in AAAD.