Impact of a half marathon on cellular immune system, pro-inflammatory cytokine levels, and recovery behavior of breast cancer patients in the aftercare compared to healthy controls

Introduction: Exercise has beneficial effects on cancer prevention as well as on prognosis of patients with cancer. To optimize the outcomes of exercise programs, more knowledge about the underlying mechanisms is needed. This study investigates the short-term effects of a half marathon on immune cell proportions, pro-inflammatory cytokine levels, and recovery behavior of patients with breast cancer in the aftercare compared to healthy controls. Methods: Nine patients with breast cancer in the aftercare and 9 healthy age-matched controls participated in a half marathon. Blood samples were collected before, after, and 24 h after the run. Immune status was measured by flow cytometer analysis, while serum levels of the pro-inflammatory cytokines TNF-alpha, IL-6, and MIF were assessed using ELISA. Recovery behavior was determined using an ADL monitor. Results: Both groups showed a similar recovery behavior and time courses in changes of granulocytes, monocytes, lymphocytes, and cytokine serum levels. Patients revealed increased proportions of cytotoxic and memory T cells, whereas helper and naive T cells were decreased compared to healthy controls. Naive and memory T-cell proportions were not affected by the intervention. Conclusions: Patients with breast cancer in the aftercare and healthy subjects show a similarly recovery behavior and immune response to the intervention. The detected differences in T-cell subsets need further investigation. Based on the results of the study, we hypothesize that immune cell subsets with known relevance in cancer were mobilized through the intervention. We confirm that the hypothesis of a midterm anti-inflammatory effect of exercise is also valid for patients with breast cancer in the aftercare