Abstract 2282: Predictive association of tumor cells hijacked NFATC2 activities with resistance to immune checkpoint inhibition in melanoma patients

Abstract Background: Immune checkpoint blockade (ICB) has emerged as an effective cancer therapy. However, only a small fraction of patients receives benefits whereas a significant subset of patients experienced severe or even lethal autoimmune diseases. Stratifying patients that would benefit from immunotherapy remain a highly unmet clinical need. Dysregulations of transcriptional programs have been implicated in cancer initiation and progression. To date, there is a paucity of studies on the predictive values of transcriptional factors on ICB response based on the most recently emerged ICB clinical trial datasets. We reasoned that cancer cells may hijack key transcriptional programs in hematological cells to evade the attack from immune cells and acquired tolerance to immunotherapy. Method: Herein, we used an R package singscore/1. 14. 0 to compute the TFs activity scores based on their validated gene targets (TGs). Leveraging melanoma clinical trial datasets, we analyzed the predictive association of the TF scores with resistance to anti-PD1 ICB. The R package, iGenSig was used to evaluate the potential confounding variables. Results: Our landscape correlation analysis revealed NFATC2 (Nuclear Factor Of Activated T Cells 2) -TGs as the most significant predictor of anti-PD-1 ICB resistance in melanoma. NFATCT-TGS as a predictor of anti-PD1 resistance is confounded by liver metastasis and achieved AUC range between 0. 71 to 0. 74 in three datasets (PRJEB23709, GSE160638, and Phs000452). In addition, prior anti-CTLA4 exposure (AUC=0. 87 and 0. 89) is associated with higher predictive efficacy of NFATC2-TGS than anti-CTLA4 naïve tumor (AUC=0. 61 and 0. 69) in phs000452 and GSE91061 datasets. Survival analysis revealed that NFATC2 is a better predictor of progressive-free survival (PFS; HR=5. 95), and overall survival (OS; HR= 3. 28-3. 38) in anti-CTLA4 exposed tumor than anti-CTLA4 naïve tumor (PFS: HR=1. 92, and OS; HR=1. 64-2. 17). Finally, NFATC2-TGS show strong inhibitory correlation with B cells and T cells infiltration, but strongly correlated with tumor purity. Conclusion: We demonstrate that NFATC2 TGS predicts ICB benefits in melanoma patients, and thus may guide the recruitment of melanoma patients for anti-PD1 ICB. Our data provide support to the hypothesis that melanoma acquired NFATC2 transcriptional program to avoid immune cells evasion and acquired tolerance to ICB immunotherapy Citation Format: Bashir Lawal, Yue Wang, Parisa Lotfinejad, Xiaosong Wang. Predictive association of tumor cells hijacked NFATC2 activities with resistance to immune checkpoint inhibition in melanoma patients 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 (6Suppl): Abstract nr 2282.