Browsing by Author "Sanders, Melinda E."

Now showing 1 - 3 of 3
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    Epithelial Expressed B7-H4 Drives Differential Immunotherapy Response in Murine and Human Breast Cancer
    (American Association for Cancer Research, 2024) Wescott, Elizabeth C.; Sun, Xiaopeng; Gonzalez-Ericsson, Paula; Hanna, Ann; Taylor, Brandie C.; Sanchez, Violeta; Bronzini, Juliana; Opalenik, Susan R.; Sanders, Melinda E.; Wulfkuhle, Julia; Gallagher, Rosa I.; Gomez, Henry; Isaacs, Claudine; Bharti, Vijaya; Wilson, John T.; Ballinger, Tarah J.; Santa-Maria, Cesar A.; Shah, Payal D.; Dees, Elizabeth C.; Lehmann, Brian D.; Abramson, Vandana G.; Hirst, Gillian L.; Brown Swigart, Lamorna; van ˈt Veer, Laura J.; Esserman, Laura J.; Petricoin, Emanuel F.; Pietenpol, Jennifer A.; Balko, Justin M.; Medicine, School of Medicine
    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.
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    Multiomics in primary and metastatic breast tumors from the AURORA US network finds microenvironment and epigenetic drivers of metastasis
    (Springer Nature, 2023) Garcia-Recio, Susana; Hinoue, Toshinori; Wheeler, Gregory L.; Kelly, Benjamin J.; Garrido-Castro, Ana C.; Pascual, Tomas; De Cubas, Aguirre A.; Xia, Youli; Felsheim, Brooke M.; McClure, Marni B.; Rajkovic, Andrei; Karaesmen, Ezgi; Smith, Markia A.; Fan, Cheng; Gonzalez Ericsson, Paula I.; Sanders, Melinda E.; Creighton, Chad J.; Bowen, Jay; Leraas, Kristen; Burns, Robyn T.; Coppens, Sara; Wheless, Amy; Rezk, Salma; Garrett, Amy L.; Parker, Joel S.; Foy, Kelly K.; Shen, Hui; Park, Ben H.; Krop, Ian; Anders, Carey; Gastier-Foster, Julie; Rimawi, Mothaffar F.; Nanda, Rita; Lin, Nancy U.; Isaacs, Claudine; Marcom, P. Kelly; Storniolo, Anna Maria; Couch, Fergus J.; Chandran, Uma; Davis, Michael; Silverstein, Jonathan; Ropelewski, Alexander; Liu, Minetta C.; Hilsenbeck, Susan G.; Norton, Larry; Richardson, Andrea L.; Symmans, W. Fraser; Wolff, Antonio C.; Davidson, Nancy E.; Carey, Lisa A.; Lee, Adrian V.; Balko, Justin M.; Hoadley, Katherine A.; Laird, Peter W.; Mardis, Elaine R.; King, Tari A.; AURORA US Network; Perou, Charles M.; Medicine, School of Medicine
    The AURORA US Metastasis Project was established with the goal to identify molecular features associated with metastasis. We assayed 55 females with metastatic breast cancer (51 primary cancers and 102 metastases) by RNA sequencing, tumor/germline DNA exome and low-pass whole-genome sequencing and global DNA methylation microarrays. Expression subtype changes were observed in ~30% of samples and were coincident with DNA clonality shifts, especially involving HER2. Downregulation of estrogen receptor (ER)-mediated cell-cell adhesion genes through DNA methylation mechanisms was observed in metastases. Microenvironment differences varied according to tumor subtype; the ER+/luminal subtype had lower fibroblast and endothelial content, while triple-negative breast cancer/basal metastases showed a decrease in B and T cells. In 17% of metastases, DNA hypermethylation and/or focal deletions were identified near HLA-A and were associated with reduced expression and lower immune cell infiltrates, especially in brain and liver metastases. These findings could have implications for treating individuals with metastatic breast cancer with immune- and HER2-targeting therapies.
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    NKG2A Is a Therapeutic Vulnerability in Immunotherapy Resistant MHC-I Heterogeneous Triple-Negative Breast Cancer
    (American Association for Cancer Research, 2024) Taylor, Brandie C.; Sun, Xiaopeng; Gonzalez-Ericsson, Paula I.; Sanchez, Violeta; Sanders, Melinda E.; Wescott, Elizabeth C.; Opalenik, Susan R.; Hanna, Ann; Chou, Shu-Ting; Van Kaer, Luc; Gomez, Henry; Isaacs, Claudine; Ballinger, Tarah J.; Santa-Maria, Cesar A.; Shah, Payal D.; Dees, Elizabeth C.; Lehmann, Brian D.; Abramson, Vandana G.; Pietenpol, Jennifer A.; Balko, Justin M.; Medicine, School of Medicine
    Despite the success of immune checkpoint inhibition (ICI) in treating cancer, patients with triple-negative breast cancer (TNBC) often develop resistance to therapy, and the underlying mechanisms are unclear. MHC-I expression is essential for antigen presentation and T-cell-directed immunotherapy responses. This study demonstrates that TNBC patients display intratumor heterogeneity in regional MHC-I expression. In murine models, loss of MHC-I negates antitumor immunity and ICI response, whereas intratumor MHC-I heterogeneity leads to increased infiltration of natural killer (NK) cells in an IFNγ-dependent manner. Using spatial technologies, MHC-I heterogeneity is associated with clinical resistance to anti-programmed death (PD) L1 therapy and increased NK:T-cell ratios in human breast tumors. MHC-I heterogeneous tumors require NKG2A to suppress NK-cell function. Combining anti-NKG2A and anti-PD-L1 therapies restores complete response in heterogeneous MHC-I murine models, dependent on the presence of activated, tumor-infiltrating NK and CD8+ T cells. These results suggest that similar strategies may enhance patient benefit in clinical trials. Significance: Clinical resistance to immunotherapy is common in breast cancer, and many patients will likely require combination therapy to maximize immunotherapeutic benefit. This study demonstrates that heterogeneous MHC-I expression drives resistance to anti-PD-L1 therapy and exposes NKG2A on NK cells as a target to overcome resistance.