Role of aerobic exercise training on tumor‐infiltrated immune cells

• Published in: The FASEB journal 2022-05, Vol.36 (S1), p.n/a
• Main Authors: Voltarelli, Vanessa A., Amano, Mariane T., Camargo, Anamaria A., Brum, Patricia C.
• Format: Article
• Language: English
• ISSN: 0892-6638; 1530-6860
• DOI: 10.1096/fasebj.2022.36.S1.R4462

Background Despite the remarkable treatment progress in the last decades, cancer remains the second leading cause of death in the world. Therefore, strategies capable of attenuating tumor initiation, progression and aggressiveness are important for reducing incidence and mortality caused by cancer. Considering this, it is well known that aerobic exercise training (AET) promotes several beneficial adaptations in the body, and it has emerged as a possible strategy to attenuate tumor progression. However, the mechanisms underlining the beneficial effects of AET on tumor progression are still unclear. Aim: Therefore, this study intended to evaluate whether AET could positively modify the tumor microenvironment, favoring infiltration of “antitumor” immune cells, and/or reducing the amount of “protumor” immune cells, consequently attenuating tumor progression. Methods To test this, Balb/c mice were submitted to a moderate intensity AET (60% of maximal aerobic capacity, 5 days/week, 1 hour/day, in a treadmill) for 1 month before being inoculated with 1x106 CT26 colon carcinoma cells (subcutaneous injection). The AET protocol was maintained during tumor progression, and the last exercise session was performed 48 hours before animals were sacrificed (9 days after tumor cells inoculation). Tumor volume and body weight were measured daily. Experimental groups were divided into control (healthy sedentary mice), CT26 SED (sedentary tumor‐bearing mice) and CT26 TR (trained tumor‐bearing mice). Tumors were harvested at day 9 and digested with collagenase IV and DNAse. After that, tumor leukocytes were separated by a Percoll gradient. Tumor‐infiltrated dendritic cells, macrophages, natural killer cells (NK), and T lymphocytes were measured by flow cytometry. Statistical analysis: Anova One‐way, Duncan post hoc, p