The Impact of Exercise Training on Breast Cancer

Abstract

Abstract. Background Breast cancer is still a major medical, social and economic problem due to the increasing prevalence and unsatisfactory treatment results. In 2013, nearly 235,000 new cases of breast cancer were reported in the United States, which accounted for 29% of all malignant neoplasms and was related to 14% risk of death. Based on current trends, over 23 million of new cases will be diagnosed by the year 2030 (1).Numerous scientific reports indicate the impact of physical activity on the development of breast cancer. However, the results are not conclusive (2-9). Westerlind et al. found that in girls aged 10-15 who were more active than their peers with a sedentary lifestyle the risk for developing breast cancer decreased by 30-50% (2). Studies on animal models also confirm this thesis. Malicka et al. demonstrated that moderate intensity training reduced the number of induced tumors in rats (4). Other studies showed that in animals physically active at puberty (rodent treadmill, tunnels and ladders), the risk of developing the disease is decreased, the possible tumor development is delayed and smaller-sized tumors are observed (5-11). Currently, a longer survival time is observed in individuals after cancer treatment who regularly exercise (12)(13)(14)(15)(16)(17). Holmes et al. demonstrated a reduction in the risk of death due to breast cancer in women who exercised (3-5 hours per week) after treatment compared to women with a sedentary lifestyle (18). Other research groups have confirmed these results (19)(20)(21)(22). Walsh et al. and Daroux-Cole et al. suggested that exercise stimulated the immune system in cancer patients (23,24). Fairey et al. found an increase in the number of NK cells in the blood of women who trained and had previously undergone breast cancer treatment (13). It should also be noted that Demarzo and Garcia demonstrated an increase of breast tumor incidence in rats after intense exercise compared to untrained rats (25). Experiments on rats are a recognized model of experimental breast cancer research. The mammary gland model of rodents shows a significant similarity to the human mammary gland. In rodents, terminal end buds are the basic structures forming the mammary ridge while in humans it is the duct lobular unit which forms the 249 This article is freely accessible online.

Effect of Exercise on Breast Cancer: A Systematic Review and Meta-analysis of Animal Experiments

“…Among the included studies, 21 studies ( Steiner et al, 2013 ; Shalamzari et al, 2014 ; Alvarado et al, 2017 ; Alizadeh et al, 2018 ; Murphy et al, 2011 ; Aveseh et al, 2015 ; Leila et al, 2015 ; Malicka et al, 2015 ; Isanejad et al, 2016 ; Cui, 2017 ; Nasiri et al, 2017 ; Lyv Di et al, 2021 ; Qi et al, 2013 ; Siewierska et al, 2018 ; Siewierska et al, 2020 ; Wen et al, 2010 ; Gholamian et al, 2020 ; Vulczak et al, 2020 ; Wennerberg et al, 2020 ) reported that exercise could decrease the tumor volume, 1 ( Faustino-Rocha et al, 2016 ) reported negative effects of exercise, and 2 ( Smeda et al, 2017 ; Garritson et al, 2019 ) reported that exercise had no effect on the tumor volume.…”

Effect of Physical Training on the Levels of Sex Hormones and the Expression of Their Receptors in Rats With Induced Mammary Cancer in Secondary Prevention Model – Preliminary Study

“…The aim of our project entitled "Impact of Physical Training on the Carcinogenesis and Progression of Rat Mammary Glands" was the assessment of the impact of physical training on the course of cancer, depending on the intensity of exercise training and the examined prevention model. The results related to primary prevention were presented by Malicka et al (13), whereas initial results related to secondary prevention were presented by Siewierska et al (14). In the present article, we report the assessment of the influence of physical activity on sex hormone levels (estradiol and progesterone) and the expression of their receptors (ER, PR), as well as the level of apoptosis of tumor cells in the model of secondary prevention.…”

“…Tissue collection. Six months following MNU administration, the animals were sacrificed (13,14). All tumors in the animals that were detected on palpation were collected and measured.…”

The immunosuppressive phenotype of tumor-infiltrating neutrophils is associated with obesity in kidney cancer patients

“…Obesity, systemic metabolism, and patient fitness are emerging as influencing factors for cancer free-survival as both preemptive measures and post-operative disease progression. [16][17][18] Obesity causes a state of chronic lowgrade inflammation, where soluble factors, such as cytokines, chemokines, and growth factors are systemically modulated. This has been shown to give rise to immunosuppressive populations, notably MDSCs, as compensatory mechanisms to counteract obesity-associated diseases.…”