Abstract 6675: Integration of associations of immune profiles in peripheral blood and tumor microenvironment with bladder cancer outcomes

Immune cell profiles in peripheral blood have been associated with bladder cancer outcomes, however, their association with response to immunotherapy and the tumor microenvironment is a major unresolved issue. Although tumor growth can be attenuated via the activation of tumor-infiltrating effector T cells, the relationship between tumor infiltration and immune activation remains unclear. This study explored the interaction between bladder cancer outcomes and immune profiles within peripheral blood and a tumor microenvironment (TME) based on DNA methylation profiles. Peripheral blood and the matched tumor FFPE DNA methylation profiles of 60 non-muscle-invasive bladder cancer (NMIBC) and 12 muscle-invasive bladder cancer (MIBC) patients. Cell-type deconvolution approaches were applied to estimate 12 peripheral immune cell-type proportions and 17 cell-type proportions within TME. We found a positive correlation between dendritic cell proportions in the TME with peripheral CD8T memory cell proportions (r = 0.35, P = 0.003) and a negative correlation between dendritic cell proportions in the TME with peripheral regulatory T cell proportions (r = -0.28, P = 0.021). In addition, monocyte cell proportions in TME had a positive correlation with peripheral B memory (r = 0.37, P = 0.002) and CD8T memory cell proportions (r = 0.43, P = 0.0002). To investigate associations of bladder cancer outcomes with immune cell profiles, using Cox proportional hazard models, we observed an association between the fraction of dendritic cells and the hazard of death (HR = 1.27, 95% CI = 1.06-1.53). Further, a high endothelial cell proportion was significantly associated with an increased hazard of death and tumor recurrence (HR = 1.06, 95% CI = 1.01-1.13) in TME. In addition, the peripheral neutrophil-to-lymphocyte ratio (HR = 1.49, 95% CI = 1.01-2.22), monocyte (HR = 1.17, 95% CI = 1.05-1.31), neutrophil (HR = 1.04, 95% CI = 1.01-1.07), and basophil (HR = 1.35, 95% CI = 1.01-1.81) cell proportions were associated with an increased hazard of death and tumor recurrence. Our results integrated the information on bladder cancer outcomes and cell profiles in TME and peripheral blood, providing biomarkers for estimating bladder cancer prognosis using genome-scale DNA methylation measures. Citation Format: Ji-Qing Chen, Lucas A. Salas, John K. Wiencke, Devin C. Koestler, Annette M. Molinaro, Angeline S. Andrew, John D. Seigne, Margaret R. Karagas, Karl T. Kelsey, Brock C. Christensen. Integration of associations of immune profiles in peripheral blood and tumor microenvironment with bladder cancer outcomes. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6675.