Abstract 101: A novel humanized mouse model recapitulates the unique TME found in patients with HIV-associated NSCLC

Abstract Among people with HIV (PWH), non-small cell lung cancer (NSCLC) is increasing in incidence, presents with more advanced disease, and portends a worse prognosis compared to the general NSCLC population. Despite effective control of viral replication with antiretroviral therapy (ART), PWH have evidence of immune dysfunction, and it is unknown whether these immune perturbations impact the tumor microenvironment (TME) to influence disease disparities.Here we preclinically model HIV-associated NSCLC using MISTRG6-A2, a humanized mouse system that is highly optimized for development of functional innate and adaptive immune cells. We compare tumor growth and immune features of HIV-infected, ART-suppressed MISTRG6-A2 hosts to uninfected hosts, with parameters informed by parallel analyses of human tissue samples obtained from PWH with NSCLC, and non-HIV controls.MISTRG6-A2 mice were engrafted with human CD34+ HSPCs from HLA-A*02-expressing donors on post-natal day 2 and intravenously infected with HIV-1 at 6 weeks of age. When HIV viral titers were >106 copies of viral RNA/ml plasma and hCD4 T cells were depleted, ART was initiated (RAL/FTC/TDF). When plasma viral RNA was undetectable and CD4 T cells recovered, NSCLC PDX tissue from HLA-A*02-expressing tumor was implanted into these HIV-infected, ART-suppressed MISTRG6-A2 mice as well as non-infected littermate controls which had received HSPCs from the same donor. HIV-infected mice displayed enhanced growth of PDX tissue (mean tumor size 206.7 mm3 vs 110.2 mm3; p < 0.05).Quantitative immunofluorescence of the TME from these hosts revealed significantly increased infiltration of CD4 and CD8 T cells in tumors of HIV-NSCLC mice (p<0.01 and 0.05, respectively); of note, enhanced T cell infiltration was restricted to tumors, with similar frequency of CD4 and CD8 T cells detected in spleen, lung and liver tissues of HIV-infected vs uninfected hosts. Staining of tumor epitopes revealed increased expression of B2M and EGFR in tumors from HIV-NSCLC mice (mean qIF scores in NSCLC vs HIV-NSCLC 3.8 × 106 vs 1.2 × 107 for B2M, p<0.001; 440 vs 1,971 for EGFR, p<0.01), consistent with our findings in samples from HIV-NSCLC tumor tissues vs NSCLC tumor tissues. Of note, elevated EGFR staining was only present in tumor tissue, not found in stromal cells or other tissues. Single cell transcriptomic analyses of the TME revealed prominent interferon and antigen presentation signatures in HIV-NSCLC tumors, as well as differential expression of immunoregulatory molecules.These results demonstrate the fidelity of the HIV-NSCLC MISTRG6-A2 system as a model for HIV-associated NSCLC and suggest EGFR-directed therapies as potentially relevant in this neglected disease. Citation Format: Melani Juric, Gabriel Kaufmann, Li Zhu, Kishu Ranjan, Kriti Agrawal, Barani Kumar Rajendran, Jyothi K. Rajashekar, Hongyu Zhao, Yuval Kluger, Brinda Emu, Kurt A. Schalper, Priti Kumar, Richard A. Flavell, Michael Chiorazzi. A novel humanized mouse model recapitulates the unique TME found in patients with HIV-associated NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 101.