Abstract B023: Using hypoxia to improve tumor infiltrating lymphocytes therapy in different subtypes of renal cell carcinoma

Abstract

BACKGROUND: Improving the long-term efficacy for advanced renal cell carcinoma (RCC) remains challenging after progression on first line therapy. Adoptive cell therapy (ACT) using tumor infiltrating lymphocytes (TIL) is a promising personalized immunotherapeutic approach to treating solid tumors. Previously, TIL therapy for clear cell RCC patients showed moderate success but did not account for the distinct immune microenvironments in different subtypes of RCC such as clear cell (ccRCC), papillary (pRCC) or unclassified (uRCC) known to have different response to immunotherapy. In addition, hypoxia plays a critical role in tumor progression and therapy resistance in RCC. Therefore, the aim of this study was to evaluate TIL expansion from different subtypes of RCC under varying oxygen concentrations. METHODS: Tumor types collected from 48 patients included ccRCC (81.25%), pRCC (16.7%) and uRCC (8.3%). Tumors were minced into fragments and cultured for 4 weeks in media supplemented with high dose IL-2 (6000 IU/mL). At the end of the 4 weeks, TIL were further expanded using a rapid expansion protocol (REP) in either 20% or 5% oxygen. TIL expansion, reactivity to autologous tumor, and phenotype were evaluated in pre-REP and post-REP samples. RESULTS: Among the ccRCC, 91.7% of the samples expanded, while 100% of the pRCC and uRCC expanded. pRCC expanded more TIL than ccRCC (1.05e8 vs 6.7e7 total TIL expanded, respectively) while uRCC expanded less than the other subtypes (2.03e7). Pre-REP reactivity against autologous tumors was high for all the subtypes (88.3%, 75% and 100% for ccRCC, pRCC and uRCC respectively). The T-cell phenotype across subtypes showed a tendency of more CD4+ T-cells and less CD8+ T-cells for pRCC and uRCC, compared to ccRCC. All subtypes that underwent REP were able to expand in both 20% and 5% O2 (hypoxia) conditions. TIL expanded in hypoxia had a significantly higher percentage of tissue resident memory T-cells (CD69+CD103+; 15.1%, p<0.0001) when compared to the pre-REP TIL population (2%) or TIL expanded at 20% O2 (3.1%). CONCLUSION: These results demonstrate the feasibility of expanding tumor-reactive TIL from different subtypes of RCC for the first time, and highlight the advantage of exposing TIL to hypoxic conditions to enhance the differentiation of resident memory T-cells in TIL products. Citation Format: Marine Potez, Mohammed Alkhouli, Johannes Ali, Michael Carter, Matthew Beatty, Shari Pilon-Thomas, Jad Chahoud. Using hypoxia to improve tumor infiltrating lymphocytes therapy in different subtypes of renal cell carcinoma [abstract]. In: Proceedings of the AACR Special Conference: Advances in Kidney Cancer Research; 2023 Jun 24-27; Austin, Texas. Philadelphia (PA): AACR; Cancer Res 2023;83(16 Suppl):Abstract nr B023.