MHC II antigen presentation pathway expression in triple-negative breast cancer.

Abstract

1066 Background: The purpose of this study was to identify gene expression differences between triple negative breast cancer (TNBC) tumors from patients who did or did not have disease relapse. Methods: 47 snap frozen macro-dissected primary TNBC tumors from treatment-naive patients, with an adequate follow up (greater than 24 months), were analyzed using RNA-seq to identify gene expression differences between patients with disease relapse and patients who did not relapse. In addition, archived de-identified primary TNBC tumors underwent standard immunohistochemical analysis with anti-CD74 and anti-HLA-DPB1 antibodies. Results: Database included 22 patients with disease relapse and 25 who did not relapse. 24 genes had significantly higher expression in tumor tissue from patients who did not relapse and 11 of these genes were integral members of the MHC II antigen presentation pathway. The 24 gene signature was significantly associated with progression free survival (PFS) (HR = 0.24; log rank p = 0.00016)....