Engaging in exercise while undergoing radiotherapy (RT) has been reported to be safe and achievable. The impact of exercise training (ET) on RT efficiency is however largely unknown. Our study aims to investigate the interactions between ET and RT on prostate cancer growth. Athymic mice received a subcutaneous injection of PPC‐1 cells and were randomly assigned to either cancer control, cancer ET, cancer RT, or cancer RT combined with ET (CaRT‐ET). Mice were sacrificed 24 days post‐injection. All three intervention groups had reduced tumor size, the most important decrease being observed in CaRT‐ET mice. Apoptotic marker cleaved caspase‐3 was not modified by ET, but enhanced with RT. Importantly, this increase was the highest when the two strategies were combined. Furthermore, NK1.1 staining and gene expression of natural killer (NK) cell receptors Klrk1 and Il2rβ were not affected by ET alone but were increased with RT, this effect being potentiated when combined with ET. Overall, our study shows that (a) ET enhances RT efficiency by potentiating NK cell infiltration, and (b) while ET alone and ET combined with RT both reduce tumor growth, the mechanisms mediating these effects are different.

In this paper of the special issue dedicated for the Olympics 2020, we put the light on an exciting facet of exercise-oncology, which may still be unknown to some audience. Accumulating convincing evidences show that exercise reduces cancer progression and recurrence mainly in colon and breast cancer patients. Interestingly, the positive effects of exercise on cancer outcomes were mainly observed when patients practiced vigorous exercise of 6 METs or more. At the molecular level, experimental studies highlighted that regular vigorous exercise could reduce tumor growth by driving changes in immune system, metabolism, hormones, systemic inflammation, angiogenesis and redox status. In the present review, we describe the main redox-sensitive mechanisms mediated by exercise. These redox mechanisms are of particular therapeutic interest as they may explain the emerging preclinical findings proving that the association of vigorous exercise with chemotherapy or radiotherapy improves the anti-cancer responses of both interventions. Clinical and preclinical studies converge to support the practice of exercise as an adjuvant therapy that improves cancer outcomes. The understanding of the underpinning molecular mechanisms of exercise in cancer can open new avenues to improve cancer care in patients.

Background: Physical activity (PA) is now considered an adjuvant therapy in cancer treatment; nevertheless, multiple barriers could reduce PA engagement during treatment. Active video games (AVGs) lead to the achievement of mild- to moderate-intensity PA and represent a promising tool for regular movement and exercise. Objective: This paper aims to review the current literature and provide updated content on the physiological and psychological effects of AVG-based interventions in patients with cancer undergoing treatment. Methods: Four electronic databases were investigated. Studies reporting on AVG interventions delivered to patients undergoing treatment were included. A total of 21 articles (17 interventions) were identified for data extraction and quality assessment. Results: A total of 362 patients with cancer participated in the studies (number of participants 3-70). The majority underwent treatment for breast, lung, prostate, hematologic, or oral or laryngeal cancer. The types and stages of cancer varied in all studies. Participants ranged in age from 3 to 93 years. Four studies included patients with pediatric cancer. The duration of interventions ranged from 2 to 16 weeks, with a minimum of 2 sessions per week and a maximum of 1 daily session. Sessions were supervised in 10 studies, and 7 included home-based interventions. AVG interventions improved endurance, quality of life, cancer-related fatigue, and self-efficacy. Effects were mixed on strength, physical function, and depression. AVGs did not affect activity level, body composition, or anxiety. Compared with standard physiotherapy, physiological effects were lower or similar, and psychological effects were higher or similar. Conclusions: Overall, our results suggest that AVGs can be recommended to patients undergoing cancer treatment, given the physiological and psychological benefits. When AVGs are proposed, supervision of the sessions should be considered as it can limit dropouts. In the future, it is important to develop AVGs that combine endurance and muscle strengthening, with the possibility of achieving moderate to high exercise intensity, depending on the physical abilities of the patients, as indicated in the World Health Organization’s recommendations.