Physiologische und molekulare Mechanismen der Wirkung von körperlicher Aktivität auf das Krebsrisiko und den Verlauf einer Krebserkrankung

Effects of Short-Term Unsupervised Exercise, Based on Smart Bracelet Monitoring, on Body Composition in Patients Recovering from Breast Cancer

OBJECTIVE

We aimed to investigate the effects of exercise, monitored and managed using smart bracelets, on body composition, and quality of life in breast cancer survivors.

METHODS

A before-and-after study was conducted in 109 patients who were in the recovery phase of breast cancer and attended the Breast Surgery Department of the Cancer Hospital of Fudan University up to December 2017. Patients were advised to adhere to at least 150 minutes of moderate-intensity exercise per week, and a smart bracelet was issued to each participant to record their daily exercise data for 3 months. Bioelectrical impedance analysis was used to observe the effects of short-term unsupervised exercise intervention on body composition in patients recovering from breast cancer. Patients completed the Functional Assessment of Cancer Therapy-Breast to assess health-related quality of life.

RESULTS

Weight, body mass index (BMI), body fat mass (BFM), fat mass index (FMI), percent body fat (PBF), arm circumference (AC), arm muscle circumference (AMC), and visceral fat area (VFA) were lower than baseline after exercising for 3 months based on data from the wearable devices (P < .05). The only significant improvement was found in the "additional concerns about breast cancer" category among the quality-of-life assessments (P < .05). The average walking time was negatively associated with BFM, PBF, and FMI, while the average calorie consumption due to running was positively associated with fat free mass (FFM).

CONCLUSION

In this study, we demonstrated that short-term exercise may be beneficial for postoperative breast cancer survivors. A wearable device could help patients track physical data easily and promote a healthier and more positive life.

Cancer Chemoprevention: Classic and Epigenetic Mechanisms Inhibiting Tumorigenesis. What Have We Learned So Far?

Cancers derive from step by step processes which are differentiated by the progressively accumulated mutations. For some tumors there is a clear progressive advancement from benign lesions to malignancy and for these, preventive screening programs exist. In such cases having those benign lesions are a clear indicator of predisposition while for some other cases, familial patterns of cancer incidence and the identification of mutations are the main indicators of higher risk for having the disease. For patients identified as having predisposition, chemoprevention is a goal and in some cases a possibility. Chemoprevention is the use of any compound, either natural or synthetic that abrogates carcinogenesis or tumor progression, through different mechanisms, some of which have already been described. For example, the classic mechanisms may involve activation of free radical scavenging enzymes, control of chronic inflammation, and downregulation of specific signaling pathways. More recently, epigenetics allowed further understanding of the chemopreventive potential of several agents, such as sulforaphane, green tea derived compounds, resveratrol, isoflavones, and others which we exploit in this review article. Throughout the text we discuss the properties compounds should have in order to be classified as chemopreventive ones and the challenges in translational research in this area, as lots of the success achieved in vitro cannot be translated into the clinical settings, due to several different drawbacks, which include toxicity, cost, dose definition, patient adherence, and regimen of use.

Review of Factors Related to the Thyroid Cancer Epidemic

Thyroid cancer is the most common endocrine cancer, of which the incidence has dramatically increased worldwide in the past few decades. The reasons for the observed rapid increase still are not fully understood, but evidence suggests that overdiagnosis, with the advancement in detection methods and screening policies, is not the sole driver of the substantial increase of the incidence. However, the effect of environmental/lifestyle factors remains speculative other than that of radiation exposure at a young age. This review tries to give a balanced view of debated factors leading to the thyroid cancer epidemic, to offer some alternatives in understanding the controversies, and to suggest potential directions in the search of modifiable risk factors to help reduce thyroid cancer.

Exercise after breast cancer treatment: current perspectives

Over the past 2 decades, great strides have been made in the field of exercise-oncology research, particularly with breast cancer. This area of research is particularly important since there are >2.8 million breast cancer survivors who are in need of an intervention that can offset treatment-related side effects. Noticeable reductions in physical fitness (ie, cardiopulmonary fitness and muscular strength), negative changes in body composition (ie, increase in body mass, decrease in lean body mass, and increase in fat mass), increased fatigue, depression, or anxiety are some of the common side effects of cancer treatments that negatively impact overall quality of life and increase the risk for the development of comorbidities. Exercise plays a vital role in improving cardiopulmonary function, psychological events, muscular strength, and endurance in breast cancer survivors, and thus should be considered as a key factor of lifestyle intervention to reverse negative treatment-related side effects. The purpose of this review is to address current perspectives on the benefits of aerobic and resistance exercise after breast cancer treatments. This review is focused on the well-established benefits of exercise on physical and emotional well-being, bone health, lymphedema management, and the postulated benefits of exercise on risk reduction for recurrence of breast cancer.

Exercise-induced changes in tumour LDH-B and MCT1 expression are modulated by oestrogen-related receptor alpha in breast cancer-bearing BALB/c mice

KEY POINTS

Monocarboxylate transporters (MCTs) and lactate dehydrogenase A (LDH-A) play important roles in sustaining the glycolytic phenotype seen in cancer. Endurance training improves aerobic capacity; however, whether endurance training alters the metabolic phenotype of a solid tumour, from the perspective of lactate metabolism, is yet to be proven. This study showed that endurance training decreases expression of the MCT1 basigin (CD147) and LDH-A , and also increases LDH-B expression in solid tumours and attenuates tumour lactate metabolism. Similar results for MCT1 and LDH-B were found with inhibition of the oestrogen-related receptor alpha (ERRα). The training effects were not additive to the ERRα effects on MCT1 and LDH-B expression in the tumour, which indicated that exercise-induced alterations in MCT1 and LDH-B expression were modulated by ERRα. These results suggest that endurance training could be a useful tool in cancer therapy, especially in basal-like and luminal-like breast carcinomas.

ABSTRACT

Several factors, including overexpression of lactate dehydrogenase (LDH) and monocarboxylate transporters (MCTs), promote an aerobic lactate production that allows some cancer cells to sustain higher proliferation rates in hostile environments outside the cell. To elucidate the effect of endurance training on the metabolic phenotype of solid tumours, we focused on the tumour expression of LDH-A, LDH-B, MCT1, MCT4, oestrogen-related receptor alpha (ERRα) and LDH isozymes in control (C), trained (T), control+XCT790 (CX) and trained+XCT790 (TX) mice. First, we found that the metabolically altered tumours from the trained animals exhibited lower values for lactate concentration than the control group. The decreased lactate concentration was associated with a shift in the tumour LDH isozyme profile towards LDH-1. These exercise-induced changes were also associated with decreases in the expression of the tumour MCT1, ERRα and CD147 in the trained animals. Secondly, the inhibition of ERRα by treatment of MC4-L2 human breast cancer cells with XCT790 (inverse agonist ligand of ERRα) before injection into the animals not only increased LDH-B expression in the tumour, but also decreased MCT1 expression in the CX group in comparison to the C group. The effects of ERRα inhibition were not additive to the training effects on the expressions of MCT1 and LDH-B in the solid tumours. In conclusion, our results suggest that exercise-induced suppression of ERRα expression modulates alterations in solid tumour expression of LDH-B and MCT1 and contributes towards the prevention of tumour development.

Physical activity and cancer survivorship

There has been an increase in the cancer survivor population in the United States over the past several decades primarily due to improvements in early detection of first malignancies and effective treatment modalities. A wealth of evidence has demonstrated that regular physical activity is associated with a lower risk of death, all-cause mortality, cancer recurrence, and several chronic diseases, including type 2 diabetes and cardiovascular disease, common comorbid conditions in people who have survived cancer. Physical activity also is a central component of weight management.

METHODS

This review summarizes the current physical activity recommendations and the evidence linking physical activity to improvements in weight management, physiological effects, and psychological health outcomes for cancer survivors.

RESULTS

The available literature suggests physical activity is safe and is positively associated with weight management, cardiorespiratory fitness, muscular strength and endurance, quality of life, fatigue, and other psychosocial factors in cancer survivors. Yet relationships related to specific cancer diagnoses, treatments, and underlying cardiometabolic mechanisms associated with survival have not been thoroughly examined in randomized controlled trials. Furthermore, factors that influence adherence to physical activity behaviors must be identified to develop effective exercise programs. The use of objective measures of physical activity and the standardization of reporting outcome measures within intervention trials are needed to complement this effort.

CONCLUSIONS

Healthcare providers should consider individual differences among cancer survivors and tailor physical activity programs to meet the individual needs of the patient to assist in the adoption and maintenance of a physically active lifestyle.

Nutrition and physical activity influence on breast cancer incidence and outcome

INTRODUCTION AND AIMS

To provide a current perspective on nutrition and physical activity influence on breast cancer.

METHODS AND RESULTS

A comprehensive literature review was conducted and selective presentation of findings follows. While some observational studies have associated higher dietary fat intake with higher breast cancer incidence, two full-scale randomized, clinical trials of dietary fat intake reduction programs were negative. However, a lifestyle intervention targeting fat intake reduction in the Women's Intervention Nutrition Study (WINS), resulted in weight loss and also reduced breast cancer recurrences in women with early stage disease. Observational studies evaluating specific nutrient intakes and dietary supplements have provided mixed results. Several observational studies find women with early stage breast cancer with lower 25-hydroxyvitamin D levels at higher recurrence risk, a finding requiring cautious interpretation. The lifestyle factor most strongly and consistently associated with both breast cancer incidence and breast cancer recurrence risk is physical activity. A meta-analyses of observational studies supports the concept that moderate recreational physical activity (about 3-4 h walking per week) may reduce breast cancer incidence and that women with early stage breast cancer who increased or maintain their physical activity may have lower recurrence risk as well. Feasibility of achieving increased physical activity and weight loss in women with early-stage breast cancer has been established. Two full-scale randomized clinical trials are evaluating weight loss/maintenance and increased physical activity in relation to recurrence risk in women with early-stage, resected breast cancer.

DISCUSSION/CONCLUSIONS

Dietary intake may influence breast cancer but influence is difficult to separate from influence of body weight. A consistent body of observational study evidence suggests higher physical activity has favorable influence on breast cancer incidence and outcome. While awaiting definitive evidence from ongoing randomized trials, breast cancer patients can reasonably be counseled to avoid weight gain and reduce body weight if overweight or obese and increase or maintain a moderate level of physical activity.

Does physical activity increase life expectancy? A review of the literature

Physical activity reduces many major mortality risk factors including arterial hypertension, diabetes mellitus type 2, dyslipidemia, coronary heart disease, stroke, and cancer. All-cause mortality is decreased by about 30% to 35% in physically active as compared to inactive subjects. The purpose of this paper was to synthesize the literature on life expectancy in relation to physical activity. A systematic PubMed search on life expectancy in physically active and inactive individuals was performed. In addition, articles comparing life expectancy of athletes compared to that of nonathletes were reviewed. Results of 13 studies describing eight different cohorts suggest that regular physical activity is associated with an increase of life expectancy by 0.4 to 6.9 years. Eleven studies included confounding risk factors for mortality and revealed an increase in life expectancy by 0.4 to 4.2 years with regular physical activity. Eleven case control studies on life expectancy in former athletes revealed consistently greater life expectancy in aerobic endurance athletes but inconsistent results for other athletes. None of these studies considered confounding risk factors for mortality. In conclusion, while regular physical activity increases life expectancy, it remains unclear if high-intensity sports activities further increase life expectancy.