Epithelial Expressed B7-H4 Drives Differential Immunotherapy Response in Murine and Human Breast Cancer

• Autores: Wescott, EC, Sun, X, Gonzalez-Ericsson, P, Hanna, A, Taylor, BC, Sanchez, V, Bronzini, J, Opalenik, SR, Sanders, ME, Wulfkuhle, J, Gallagher, RI, Gomez, H, Isaacs, C, Bharti, V, Wilson, JT, Ballinger, TJ, Santa-Maria, CA, Shah, PD, Dees, EC, Lehmann, BD, Abramson, VG, Hirst, GL, Swigart, LB, van't, Veer, LJ, Esserman, LJ, Petricoin, EF, Pietenpol, JA, Balko, JM
• Formato: artículo
• Fecha de Publicación: 2024
• Institución: Instituto Nacional de Enfermedades Neoplásicas
• Repositorio: INEN-Institucional
• Lenguaje: inglés
• OAI Identifier: oai:repositorio.inen.sld.pe:20.500.14703/360
• Enlace del recurso: https://hdl.handle.net/20.500.14703/360
• Nivel de acceso: acceso abierto
• Materia: B7-H4; Immunotherapy; https://purl.org/pe-repo/ocde/ford#3.02.21

Combinations of immune checkpoint inhibitors (ICI, including anti-PD-1/PD-L1) and chemotherapy have been FDA approved for metastatic and early-stage triple-negative breast cancer (TNBC), but most patients do not benefit. B7-H4 is a B7 family ligand with proposed immunosuppressive functions being explored as a cancer immunotherapy target and may be associated with anti-PD-L1 resistance. However, little is known about its regulation and effect on immune cell function in breast cancers. We assessed murine and human breast cancer cells to identify regulation mechanisms of B7-H4 in vitro. We used an immunocompetent anti-PD-L1–sensitive orthotopic mammary cancer model and induced ectopic expression of B7-H4. We assessed therapy response and transcriptional changes at baseline and under treatment with anti-PD-L1. We observed B7-H4 was highly associated with epithelial cell status and transcription factors and found to be regulated by PI3K activity. EMT6 tumors with cell-surface B7-H4 expression were more resistant to immunotherapy. In addition, tumor-infiltrating immune cells had reduced immune activation signaling based on transcriptomic analysis. Paradoxically, in human breast cancer, B7-H4 expression was associated with survival benefit for patients with metastatic TNBC treated with carboplatin plus anti-PD-L1 and was associated with no change in response or survival for patients with early breast cancer receiving chemotherapy plus anti-PD-1. While B7-H4 induces tumor resistance to anti-PD-L1 in murine models, there are alternative mechanisms of signaling and function in human cancers. In addition, the strong correlation of B7-H4 to epithelial cell markers suggests a potential regulatory mechanism of B7-H4 independent of PD-L1. Significance: This translational study confirms the association of B7-H4 expression with a cold immune microenvironment in breast cancer and offers preclinical studies demonstrating a potential role for B7-H4 in suppressing response to checkpoint therapy. However, analysis of two clinical trials with checkpoint inhibitors in the early and metastatic settings argue against B7-H4 as being a mechanism of clinical resistance to checkpoints, with clear implications for its candidacy as a therapeutic target. © 2024 The Authors; Published by the American Association for Cancer Research.