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bioRxiv · 10.1101/2021.09.24.461709

KEAP1 mutation in lung adenocarcinoma promotes immune evasion and immunotherapy resistance

Abstract

Lung cancer treatment has benefited greatly from the development of effective immune-based therapies. However, these strategies still fail in a large subset of patients. Tumor-intrinsic mutations can drive immune evasion via recruiting immunosuppressive populations or suppressing anti-tumor immune responses. KEAP1 is one of the most frequently mutated genes in lung adenocarcinoma patients and is associated with poor prognosis and inferior response to all therapies, including checkpoint blockade. Here, we established a novel antigenic lung cancer model and showed that Keap1-mutant tumors promote dramatic remodeling of the tumor immune microenvironment. Combining single-cell technology and depletion studies, we demonstrate that Keap1-mutant tumors diminish dendritic cell and T cell responses driving immunotherapy resistance. Importantly, analysis of KEAP1 mutant patient tumors revealed analogous decrease in dendritic cell and T cell infiltration. Our study provides new insight into the role of KEAP1 mutations in promoting immune evasion and suggests a path to novel immune-based therapeutic strategies for KEAP1 mutant lung cancer. Statement of significanceThis study establishes that tumor-intrinsic KEAP1 mutations contribute to immune evasion through suppression of dendritic cell and T cell responses, explaining the observed resistance to immunotherapy of KEAP1 mutant tumors. These results highlight the importance of stratifying patients based on KEAP1 status and paves the way for novel therapeutic strategies.

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BibTeXRIS

Zavitsanou, A. M., Hao, Y., Wu, W. L., Bartnicki, E., Pillai, R., Karakousi, T., Herrera, A., Karatza, A., Rashidfarrokhi, A., Solis, S., Ciampricotti, M., Yeaton, A. H., Ivanova, E., Wohlhieter, C. A., Buus, T. B., Poirier, J. T., Rudin, C. M., Wong, K.-K., Moreira, A. L., Khanna, K. M., Tsirigos, A., Papagiannakopoulos, T., Koralov, S. B.. 2021-09-25. KEAP1 mutation in lung adenocarcinoma promotes immune evasion and immunotherapy resistance. https://doi.org/10.1101/2021.09.24.461709

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