Abstract
Lung adenocarcinoma (LUAD) patients with elevated breast cancer susceptibility gene 1 (BRCA1) expression had markedly worse overall survival and progression-free survival compared to those with reduced BRCA1 levels. In contrast, BRCA1 expression did not correlate with survival outcomes in squamous cell carcinoma patients. The overexpression of BRCA1 was an independent risk factor for LUAD and was indicative of an immune-suppressive tumor microenvironment.