Pan-cancer analysis and experimental validation identify CYP19A1 as a prognostic biomarker and oncogenic driver associated with tumor immune microenvironment regulation in gastrointestinal cancers

Abstract Background: CYP19A1, which encodes the enzyme aromatase necessary for estrogen production, is known to be involved in hormone-sensitive cancers, but its role in gastrointestinal cancers is not completely clear. Methods: To examine CYP19A1 in gastrointestinal cancers, we carried out pan-cancer bioinformatics analyses using the TCGA dataset as the main source, combined with experimental validations. A systematic analysis was conducted on transcriptomic, clinical, epigenetic, immune infiltration data, functional networks, and regulatory mechanisms. Functional experiments were conducted using mouse models of