Abstract
HER2-low expression is associated with hormone receptor (HR) expression in HR-positive breast cancer. We aimed to evaluate its association with androgen receptor (AR) among 196 patients with metastatic triple-negative breast cancer (mTNBC). Central determination of AR showed significant enrichment in HER2-low compared with HER2-0 mTNBC (mean: 33.7% vs. 21.4%, p = 0.038), whereas no significant immunological differences were observed. HER2-low/AR-positive patients trended towards longer overall survival, highlighting the potential relevance of these biomarkers.
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Acknowledgements
This study was funded by the Terri Brodeur Breast Cancer Foundation, a METAvivor Early Career Investigator Award, the Elaine and Eduardo Saverin Foundation, Mehlman Family Funds, Benderson Family Funds, Breast Cancer Research Foundation, and Susan G. Komen. The authors acknowledge Kaitlyn T. Bifolck, full-time employee of Dana-Farber Cancer Institute, for providing editorial assistance in the preparation of this manuscript.
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Conceptualization: P.T., J.C., S.M.T.; Data curation: P.T., X.C., N.T., B.B.K., S.J.S.; Formal analysis: X.C., N.T.; Funding acquisition: P.T., S.M.T.; Investigation: P.T., J.C., X.C., N.T., S.G., S.M.T., B.B.K., S.J.S.; Methodology: P.T., J.C., X.C., N.T.; Project administration: P.T., S.M.T.; Resources: P.T., S.M.T.; Software: X.C., N.T.; Supervision: P.T., S.M.T., N.T.; Validation: P.T., S.M.T., N.T.; Visualization: P.T., J.C., X.C., N.T.; Writing – original draft: P.T., J.C.; Writing – review & editing: P.T., J.C., B.B.K., X.C., B.J., A.Z., M.H., D.R., M.D., E.W., R.J., N.U.L., J.C., Y.S.C., T.L., N.T., E.A.M., S.J.S., S.G., S.M.T.
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P.T. reports consulting fees from AstraZeneca, Daiichi Sankyo, Gilead, Genentech/Roche, Novartis, Menarini/Stemline, and Eli Lilly. NUL reports institutional research support from Genentech, Pfizer, Merck, Seattle Genetics, Zion Pharmaceuticals, Olema Pharmaceuticals, and AstraZeneca; consulting honoraria from Seattle Genetics, Daiichi Sankyo, AstraZeneca, Olema Pharmaceuticals, Stemline/Menarini, Artera Inc., Eisai, and Shorla Oncology; royalties from Up to date (book); and travel support from Olema Pharmaceuticals, AstraZeneca, and Daiichi Sankyo. SMT reports consulting or advisory roles for Novartis, Pfizer/SeaGen, Merck, Eli Lilly, AstraZeneca, Genentech/Roche, Eisai, Bristol Myers Squibb/Systimmune, Daiichi Sankyo, Gilead, Blueprint Medicines, Reveal Genomics, Sumitovant Biopharma, Artios Pharma, Menarini/Stemline, Aadi Bio, Bayer, Jazz Pharmaceuticals, Natera, Tango Therapeutics, eFFECTOR, Hengrui USA, Cullinan Oncology, Circle Pharma, Arvinas, BioNTech, Johnson&Johnson/Ambrx, Launch Therapeutics, Zuellig Pharma, Bicycle Therapeutics, BeiGene Therapeutics, Mersana, Summit Therapeutics, Avenzo Therapeutics, Aktis Oncology, Celcuity, Boehringer Ingelheim, Samsung Bioepis, Olema Pharmaceuticals, Tempus, and Boundless Bio; institutional research funding from Genentech/Roche, Merck, Exelixis, Pfizer, Lilly, Novartis, Bristol Myers Squibb, AstraZeneca, Gilead, NanoString Technologies, Seattle Genetics, OncoPep, Daiichi Sankyo, Menarini/Stemline, Jazz Pharmaceuticals, and Olema Pharmaceuticals; and travel support from Eli Lilly, Gilead, Jazz Pharmaceuticals, Pfizer, Arvinas, and Roche.
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Tarantino, P., Cha, J., Binboga Kurt, B. et al. Androgen receptor expression and immune characteristics of HER2-low metastatic triple-negative breast cancer. npj Breast Cancer (2026). https://doi.org/10.1038/s41523-026-00913-4
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DOI: https://doi.org/10.1038/s41523-026-00913-4
