Tumor immune microenvironment of self-identified African American and non-African American triple negative breast cancer

• Published in: NPJ breast cancer Vol. 8; no. 1; p. 88
• Main Authors: Marczyk, Michal, Qing, Tao, O’Meara, Tess, Yagahoobi, Vesal, Pelekanou, Vasiliki, Bai, Yalai, Reisenbichler, Emily, Cole, Kimberly S., Li, Xiaotong, Gunasekharan, Vignesh, Ibrahim, Eiman, Fanucci, Kristina, Wei, Wei, Rimm, David L., Pusztai, Lajos, Blenman, Kim R. M.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 22.07.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 631/337/2019; 631/67/327; 631/67/580; 692/308/575; 692/4028/67/1347; African Americans; Antigen presentation; Biology; Biomedical and Life Sciences; Biomedicine; Breast cancer; Cancer Research; Cancer therapies; Cell adhesion & migration; Cell Biology; Chemotherapy; Clinical outcomes; Diabetes; Gene expression; Genomics; Hispanic Americans; Histology; Human Genetics; Hypertension; Internal medicine; Medical prognosis; Medicine; Metabolism; Mutation; Neutrophils; Oncology; Patients; Socioeconomic factors
• ISSN: 2374-4677; 2374-4677
• DOI: 10.1038/s41523-022-00449-3

Differences in the tumor immune microenvironment may result in differences in prognosis and response to treatment in cancer patients. We hypothesized that differences in the tumor immune microenvironment may exist between African American (AA) and NonAA patients, due to ancestry-related or socioeconomic factors, that may partially explain differences in clinical outcomes. We analyzed clinically matched triple-negative breast cancer (TNBC) tissues from self-identified AA and NonAA patients and found that stromal TILs, PD-L1 IHC-positivity, mRNA expression of immune-related pathways, and immunotherapy response predictive signatures were significantly higher in AA samples ( p  < 0.05; Fisher’s Exact Test, Mann–Whitney Test, Permutation Test). Cancer biology and metabolism pathways, TAM-M2, and Immune Exclusion were significantly higher in NonAA samples ( p  < 0.05; Permutation Test, Mann–Whitney Test). There were no differences in somatic tumor mutation burden. Overall, there is greater immune infiltration and inflammation in AA TNBC and these differences may impact response to immune checkpoint inhibitors and other therapeutic agents that modulate the immune microenvironment.