182P Innovative nano-immunotherapy for modulating tumor-immune interactions and microbiome in pancreatic cancer

Background: Exercise training reduces tumour growth by increasing tumour-infiltrating T cell density in preclinical models.However, it remains unknown whether exercise training can modify intratumoural T cells in humans.Objective: To compare the effects of exercise training intervention versus control on human prostate intratumoural T cell density.Methods: This study is a secondary analysis of a randomised controlled trial.We randomly allocated men (age >18 years) with treatment-nave localized prostate cancer scheduled to radical prostatectomy 2:1 to exercise training intervention or control.The exercise intervention consisted of supervised, high-intensity interval bicycling four times per week from the time of randomization until prostatectomy.Intratumoural CD3 + and CD8 + T cell densities in diagnostic biopsies and post-surgical prostatectomy specimens were quantified using immunohistochemistry. Betweengroup differences in changes from baseline to follow-up were estimated using constrained baseline linear mixed-effect models.Results: A total of 30 participants were included (exercise intervention, n20; control, n10).We found no between-group differences in changes in CD3 + (mean difference [95% Cis]: e17 [e185; 150] cells/mm 2 ) or CD8 + (mean difference [95% CI]: e 16 [e206;172] cells/mm 2 ) T cells.Additionally, we found no statistically significant correlations between changes in T cell density and the number of attended exercise training sessions or changes in maximal oxygen consumption. Conclusions:In this secondary analysis of a randomised controlled trial, we found no impact of exercise training on tumour-infiltrating CD3 + and CD8 + T cell density in human prostate cancer.Clinical trial identification: Local Ethics Committee of the Capital Region of Denmark (H-18020711).All participants provided informed consent before performing any study-related procedures, and the study was preregistered at www.clinicaltrials.gov(NCT03675529).