Exercise and lymphocyte activation following chemotherapy for breast cancer

Effects of different types of exercise on inflammatory markers in cancer patients: A systematic review and Bayesian network meta-analysis

This systematic review and network meta-analysis (NMA) was to investigate the effects of different exercise modalities on inflammatory markers in cancer patients. Using the standardized mean difference (SMD) as the effect size, a Bayesian random-effects network meta-analysis and regression analysis were conducted. Searches were performed across five databases for randomized controlled trials (RCTs) involving cancer patients, with exercise as the intervention, reported outcomes related to inflammatory markers, and interventions lasting more than four weeks, up to June 2024. A total of 57 RCTs (3106 patients) were included. The Cochrane risk of Bias Tool was utilized to assess the RCTs, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) tool was employed to evaluate the quality of evidence. NMA results indicate that regular exercise is effective in reducing inflammation in cancer patients, with combined high-intensity aerobic and resistance exercises proving to be the most beneficial. The type, intensity, and total volume of exercise are critical factors in achieving positive outcomes. It is recommended to design exercise programs for cancer patients that combine aerobic and resistance training, with a gradual increase in intensity to ensure safety.

Effects of Exercise on Cancer-Related Fatigue in Breast Cancer Patients: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

The primary objective of this study was to assess the influence of exercise interventions on cancer-related fatigue (CRF), specifically in breast cancer patients, with the ultimate goal of establishing an optimal exercise prescription for breast cancer patients. A comprehensive search was undertaken across multiple databases, including Embase, PubMed, Cochrane Library, Web of Science, and Scopus, covering data published up to 1 September 2023. A meta-analysis was conducted to calculate the standardized mean difference (SMD) along with its corresponding 95% confidence interval (CI), thereby quantifying the effectiveness of exercise in alleviating CRF in the breast cancer patient population. Twenty-six studies met the inclusion criteria. Aerobic exercise (SMD, -0.17, p = 0.02), resistance exercise (SMD, -0.37, p = 0.0009), and combined exercise (SMD, -0.53, p < 0.0001) significantly improved CRF in breast cancer patients. In addition, exercise intervention conducted ≥3 times per week (SMD, -0.47, p = 0.0001) for >60 min per session (SMD, -0.63, p < 0.0001) and ≥180 min per week (SMD, -0.79, p < 0.0001) had greater effects on improving CRF in breast cancer patients, especially middle-aged patients (SMD, -0.42, p < 0.0001). Exercise is an effective approach to improving CRF in breast cancer patients. When devising an exercise program, the primary consideration should be the incorporation of combined exercise as the principal intervention. This entails ensuring that participants engage in the program at least three times weekly, with each session lasting for more than 60 min. The ultimate aim is to achieve a total weekly exercise duration of 180 min by progressively increasing the frequency of exercise sessions.

Combined Aerobic and Resistance Training Improves Body Composition, Alters Cardiometabolic Risk, and Ameliorates Cancer-Related Indicators in Breast Cancer Patients and Survivors with Overweight/Obesity: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Breast cancer survivors with obesity are at a high risk of cancer recurrence, comorbidity, and mortality. This review aims to systematically evaluate the effects of combined aerobic and resistance training (CART) on body composition, lipid homeostasis, inflammation, adipokines, cancer-related fatigue, sleep, and quality of life in breast cancer patients and survivors with overweight/obesity. An electronic search was conducted in PubMed, Web of Science, Scopus, Science Direct, Cochrane, and Google Scholar databases from inception up to January 8, 2024. Randomized controlled trials (RCTs) meeting the inclusion criteria were selected for the analysis. The Cochrane risk of bias tool was used to assess eligible studies, and the GRADE method to evaluate the quality of evidence. A random-effects model was used, and data were analyzed using mean (MD) and standardized mean differences (SMD) for continuous variables with 95% confidence intervals (CI). We assessed the data for risk of bias, heterogeneity, sensitivity, reporting bias, and quality of evidence. A total of 17 randomized controlled trials were included in the systematic review involving 1,148 female patients and survivors (mean age: 54.0 ± 3.4 years). The primary outcomes showed significant improvements in body mass index (SMD -0.57 kg/m2, p = 0.04), body fat (SMD -0.50%, p = 0.02), fat mass (SMD -0.63 kg, p = 0.04), hip circumference (MD -3.14 cm, p = 0.02), and fat-free mass (SMD 1.03 kg, p < 0.001). The secondary outcomes indicated significant increases in high-density lipoprotein cholesterol (MD -0.05 mmol/L, p = 0.008), natural killer cells (SMD 0.42%, p = 0.04), reductions in triglycerides (MD -81.90 mg/dL, p < 0.01), total cholesterol (SMD -0.95 mmol/L, p < 0.01), tumor necrosis factor α (SMD -0.89 pg/mL, p = 0.03), and leptin (SMD -0.63 ng/mL, p = 0.03). Also, beneficial alterations were found in cancer-related fatigue (SMD -0.98, p = 0.03), sleep (SMD -1.17, p < 0.001), and quality of life (SMD 2.94, p = 0.02) scores. There was very low to low confidence in the estimated effect of most of the outcomes. The present findings reveal that CART could be considered an adjunct therapy in supporting the conventional clinical approach observed following exercise. However, further high-quality research is needed to evaluate whether CART would be a valuable intervention to lower aggressive pharmacologic use in breast cancer patients with overweight/obesity.

The Influence of Exercise on Cancer Risk, the Tumor Microenvironment and the Treatment of Cancer

There are several modifiable factors that can be targeted to prevent and manage the occurrence and progression of cancer, and maintaining adequate exercise is a crucial one. Regular physical exercise has been shown to be a beneficial strategy in preventing cancer, potentially amplifying the effectiveness of established cancer therapies, alleviating certain cancer-related symptoms, and possibly mitigating side effects resulting from treatment. Nevertheless, the exact mechanisms by which exercise affects tumors, especially its impact on the tumor microenvironment (TME), remain uncertain. This review aims to present an overview of the beneficial effects of exercise in the context of cancer management, followed by a summary of the exercise parameters, especially exercise intensity, that need to be considered when prescribing exercise for cancer patients. Finally, we discuss the influence of exercise on the TME, including its effects on crucial immune cells (e.g., T cells, macrophages, neutrophils, natural killer cells, myeloid-derived suppressor cells, B cells), intratumor angiogenesis, and cancer metabolism. This comprehensive review provides up-to-date scientific evidence on the effects of exercise training on cancer and offers guidance to clinicians for the development of safe and feasible exercise training programs for cancer patients in clinical practice.

Effects of exercise on immune cells with tumor-specific activity in breast cancer patients and survivors: a systematic review and meta-analysis

Exercise is effective for improving the physical and psychological health of breast cancer patients. However, there is still controversy around its role on the immune system. Therefore, this systematic review and meta-analysis is aimed to evaluate the effect of chronic exercise on the number and activity of the immune cells that can contribute to anti-tumor immune responses, such as natural killers (NK) cells, CD + 4, or CD + 8. The main hypothesis of this study was that exercise could improve the immune system or, at least, there will not be a reduction in the number or activity of immune cells because of exercise. The search was conducted in the PubMed and Web of Science databases. Out of 244 studies reviewed, 10 studies met the inclusion criteria. The studies included in the meta-analyses showed mixed results and no significant (p > 0.05) positive or negative effects of exercise interventions in women with breast cancer. Therefore, the current evidence indicates that exercise does not significantly improve or reduce the immune system; thus, the prescription of exercise must not be discouraged due to the effects on the number and activity of immune system cells, but should be recommended due to the well-known benefits in quality of life, physical function or fatigue, and the absence of negative effects on the immune system. Further studies are needed to evaluate the effects according to the type of exercise, the type of cancer, or the timing of the intervention.

Physical Exercise and the Hallmarks of Breast Cancer: A Narrative Review

Growing evidence suggests that, among the different molecular/cellular pathophysiological mechanisms associated with cancer, there are 14 hallmarks that play a major role, including: (i) sustaining proliferative signaling, (ii) evading growth suppressors, (iii) activating invasion and metastasis, (iv) enabling replicative immortality, (v) inducing angiogenesis, (vi) resisting cell death, (vii) reprogramming energy metabolism, (viii) evading immune destruction, (ix) genome instability and mutations, (x) tumor-promoting inflammation, (xi) unlocking phenotypic plasticity, (xii) nonmutational epigenetic reprogramming, (xiii) polymorphic microbiomes, and (xiv) senescent cells. These hallmarks are also associated with the development of breast cancer, which represents the most prevalent tumor type in the world. The present narrative review aims to describe, for the first time, the effects of physical activity/exercise on these hallmarks. In summary, an active lifestyle, and particularly regular physical exercise, provides beneficial effects on all major hallmarks associated with breast cancer, and might therefore help to counteract the progression of the disease or its associated burden.

Behavioral factors to modulate immunotherapy efficacy in cancer

Immune checkpoint inhibitors, including anti-PD-1 and anti-CTLA-4 therapies, are used to (re)activate the immune system to treat cancer. Despite promising results, a large group of patients does not respond to checkpoint inhibition. In the vulnerability-stress model of behavioral medicine, behavioral factors, such as stress, exercise and classical pharmacological conditioning, predict cancer incidence, recurrence and the efficacy of conventional cancer treatments. Given the important role of the immune system in these processes, certain behavior may be promising to complement immune checkpoint inhibition therapy. Here, we discuss the preliminary evidence and suitability of three behavioral mechanisms, i.e. stress modulation, exercise and classical pharmacological conditioning for the benefit of immunotherapy. It is crucial to study the potential beneficial effects of behavioral strategies that support immunotherapeutic anti-tumor effects with rigorous experimental evidence, to exploit behavioral mechanisms in improving checkpoint inhibition efficacy.

Physical Activity as the Best Supportive Care in Cancer: The Clinician's and the Researcher's Perspectives

Multidisciplinary supportive care, integrating the dimensions of exercise alongside oncological treatments, is now regarded as a new paradigm to improve patient survival and quality of life. Its impact is important on the factors that control tumor development, such as the immune system, inflammation, tissue perfusion, hypoxia, insulin resistance, metabolism, glucocorticoid levels, and cachexia. An increasing amount of research has been published in the last years on the effects of physical activity within the framework of oncology, marking the appearance of a new medical field, commonly known as "exercise oncology". This emerging research field is trying to determine the biological mechanisms by which, aerobic exercise affects the incidence of cancer, the progression and/or the appearance of metastases. We propose an overview of the current state of the art physical exercise interventions in the management of cancer patients, including a pragmatic perspective with tips for routine practice. We then develop the emerging mechanistic views about physical exercise and their potential clinical applications. Moving toward a more personalized, integrated, patient-centered, and multidisciplinary management, by trying to understand the different interactions between the cancer and the host, as well as the impact of the disease and the treatments on the different organs, this seems to be the most promising method to improve the care of cancer patients.

Effects of physical exercise on body fat and laboratory biomarkers in cancer patients: a meta-analysis of 35 randomized controlled trials

BACKGROUND

A growing number of articles had reported the beneficial effects of physical exercise on reduced risks of cancer recurrence and mortality. However, the associations between physical exercise and laboratory biomarkers still had controversy. As we knew, this meta-analysis of randomized controlled trials (RCTs) was the first time for us to comprehensively clarify their relationships in cancer patients.

METHODS

We comprehensively searched the PubMed, Cochrane Central, EMBASE, Web of Science, and SportDiscus online databases to identify eligible articles, up to June 1, 2021. Pooled standardized mean differences (SMDs) with 95% confidence intervals (CIs) were utilized to clarify their associations. Sensitivity analysis was performed to assess the impact of the individual on overall and Begg's/Egger's plot was utilized to evaluate potential publication bias.

RESULTS

Finally, 35 randomized controlled trials (RCTs) were finally enrolled in this meta-analysis. Our results indicated that physical exercise could significantly reduce BMI (pooled SMD = -0.32 - 0.56 to -0.09)), body weight (pooled SMD = -0.31 (-0.54 to -0.08)), body fat (pooled SMD = -0.44 (-0.70 to -0.18)), waist circumference (pooled SMD = -0.50 (-0.76 to -0.23)), hip circumference (pooled SMD = -0.54 (-0.80 to -0.28)), triglyceride (pooled SMD = -0.35 (-0.69 to -0.02)), fasting insulin (pooled SMD = -0.38 (-0.54 to -0.22)), glucose (pooled SMD = -0.56 (-0.84 to -0.28)), insulin resistance (pooled SMD = -0.40 (-0.72 to -0.07)), CRP (pooled SMD = -0.97 (-1.48 to -0.46)), IGF-1 levels (pooled SMD = -0.56 (-0.83 to -0.29)) and remarkably increase IGFBP-3 levels (pooled SMD = 0.81 (0.45 to 1.17)). Further sensitivity analysis and Begg's or Egger's test suggested that our results were robust with no significant publication bias.

CONCLUSIONS

Our results shed light on the beneficial effects of physical exercise on cancer patients by means of BMI/weight change and various biomarkers alteration (insulin-glucose pathways or inflammatory biomarkers). Our results were anticipated for clinical application to improve cancer patients' prognosis.

The importance of physical exercise in cardiovascular fitness in breast cancer survivors. A cross-sectional study: women in Motion 2.0

PURPOSE

To compare the cardiovascular fitness of breast cancer (BC) survivors with an active lifestyle to those with a sedentary lifestyle.

METHODS

A cross-sectional study was conducted. Participants were classified into four groups: two groups of active women who performed more than 150 min/week of physical exercise, active with BC (Act-BCW) and active without BC (Act-HW); and two groups of sedentary women who performed less than 90 min/week of physical exercise, sedentary with BC (Sed-BCW) and sedentary without BC (Sed-HW). VO₂max was estimated by the 6-min walking test (6MWT); speed, isometric strength, lower body maximum strength, explosive strength, balance, and body composition were also measured. ANOVA was used to analyze group differences and post hoc comparisons were developed with the Bonferroni test.

RESULTS

A total of 92 women were recruited. Significant differences were found in VO₂max between the Act-BCW and Sed-BCW groups (MeanDif = 5.86, p < 0.001). No differences in VO₂max were observed between the active groups (MeanDif = 0.42, p = 0.753). Related body composition and fat mass levels were significantly lower in the Act-BCW group than in the sedentary groups (Sed-BCW MeanDif =  - 6.78; p = 0.012; and Sed-HW MeanDif =  - 12.07; p < 0.001).

CONCLUSIONS

Women who are Act-BCW can achieve similar values in physical condition as women who are Act-HW and have better values than women who are sedentary. Furthermore, our results suggest than physical activity level may have a greater impact in body composition than a previous history of BC.

The Effects of 16 Weeks of Exercise Training on Neutrophil Functions in Breast Cancer Survivors

Following therapy, breast cancer survivors (BCS) have an increased risk of infections because of age and cancer dysregulation of inflammation and neutrophil functions. Neutrophil functions may be improved by exercise training, although limited data exist on exercise and neutrophil functions in BCS.Sixteen BCS [mean age: 56 (SD 11) years old] completed 16 weeks of community-based exercise training and a 45-minute acute bout of cycling before (Base) and after (Final) the exercise training program. Exercise training consisted of 3 x 40 – 60 minute mixed mode aerobic exercises, comprising 10 – 30 minutes aerobic and 30 minutes resistance training. At Base and Final, we took BCS blood samples before (PRE), immediately after (POST), and 1 hour after (1Hr) acute exercise to determine neutrophil counts, phenotype, bacterial killing, IL-6, and IL-8 levels. Eleven healthy, age- and physical activity levels-matched women (Control) completed the acute bout of exercise once as a healthy response reference. Resting Responses. BCS and Controls had similar Base PRE absolute neutrophil counts [mean (SD): 3.3 (1.9) v 3.1 (1.2) x 10⁹/L, p=0.801], but BCS had lower bacterial phagocytosis [3991 (1233) v 4881 (417) MFI, p=0.035] and higher oxidative killing [6254 (1434) v 4709 (1220) MFI, p=0.005], lower CD16 [4159 (1785) v 7018 (1240) MFI, p<0.001], lower CXCR2 [4878 (1796) v 6330 (1299) MFI, p=0.032] and higher TLR2 [98 (32) v 72 (17) MFI, p=0.022] expression, while IL-6 [7.4 (5.4) v 4.0 (2.7) pg/mL, p=0.079] levels were marginally higher and IL-8 [6.0 (4.7) v 7.9 (5.0) pg/mL, p=0.316] levels similar. After 16 weeks of training, compared to Controls, BCS Final PRE phagocytosis [4510 (738) v 4881 (417) MFI, p=0.146] and TLR2 expression [114 (92) v 72 (17) MFI, p=0.148] were no longer different. Acute Exercise Responses. As compared to Controls, at Base, BCS phagocytic Pre-Post response was lower [mean difference, % (SD): 12% (26%), p=0.042], CD16 Pre-Post response was lower [12% (21%), p=0.016] while CD16 Pre-1Hr response was higher [13% (25%), p=0.022], TLR2 Pre-Post response was higher [15% (4%) p=0.002], while IL-8 Pre-Post response was higher [99% (48%), p=0.049]. As compared to Controls, following 16 weeks of training BCS phagocytic Pre-Post response [5% (5%), p=0.418], CD16 Pre-1Hr response [7% (7%), p=0.294], TLR2 Pre-Post response [6% (4%), p=0.092], and IL-8 Pre-Post response [1% (9%), p=0.087] were no longer different. Following cancer therapy, BCS may have impaired neutrophil functions in response to an acute bout of exercise that are partially restored by 16 weeks of exercise training. The improved phagocytosis of bacteria in BCS may represent an exercise-induced intrinsic improvement in neutrophil functions consistent with a reduced risk of infectious disease.

The effects of exercise training on inflammatory biomarkers in patients with breast cancer: A systematic review and meta-analysis

OBJECTIVE

Despite several studies on the effects of exercise training on inflammatory biomarkers in patients with breast cancer, no earlier study has systematically summarized their findings. Current systematic review and meta-analysis has been done on earlier clinical trials in this topic.

METHOD

Relevant studies published up to August 2021 were searched through PubMed, MEDLINE, SCOPUS, EMBASE, and Google Scholar using predefined keywords. Studies that examined the effect of exercise training on inflammatory biomarkers in adult women with breast cancer were included.

RESULT

A total of 18 studies were included. Combining 11 effect sizes, exercise training significantly reduced CRP level (WMD: -0.55; 95% CI: -1.10, -0.01). However, it had no significant influence on serum TNF-α (WMD: -0.40; 95% CI: -1.30, 0.50) and IL-6 concentrations (WMD: -0.05, 95% CI: -0.53, 0.43) in 8 and 15 studies, respectively. Pooling 7 effect sizes, we failed to find significant changes in IL-8 following exercise training (WMD: -0.65, 95% CI: -1.57, 0.28). Moreover, we reached no significant findings for serum levels of INF-ɣ (WMD: -2.66, 95% CI: -7.67, 2.36), IL-1β (WMD: 0.03, 95% CI: -0.26, 0.21), and IL-10 (WMD: -0.70, 95% CI: -2.92, 1.52). Based on subgroup analyses, best findings were reached in long-term intervention and after concurrent training.

DISCUSSION

Chronic inflammation is hypothesized to be associated with breast cancer development. We found significant reduction in CRP level following exercise training, which was more considerable after concurrent aerobic and resistance training and in long-term intervention. No significant changes were seen in serum levels of TNF-α, IL-6, IL-8, IL-10, INF-ɣ, IL-1β following exercise training. Further studies are needed to find more details.

Dudrick Research Symposium: Expanding the boundaries of cancer care through nutrition support

The 2020 Dudrick Research Symposium, entitled "Expanding the Boundaries of Cancer Care Through Nutritional Support," was held on March 30, at the American Society for Parenteral and Enteral Nutrition (ASPEN), Nutrition Science & Practice Conference. It was scheduled to take place in Tampa, Florida, but had to be held virtually. The Dudrick Symposium honors the many pivotal and innovative contributions made by the late Dr Stanley J. Dudrick, physician scientist, academic leader, and a founding member of ASPEN. This year, in addition to honoring his legacy, we honored his life. As the 2019 recipient of the Dudrick Research Scholar Award, Dr Pimiento chaired the symposium. The presentations focused on discussing the history, the present and future frontiers in the overlapping fields of nutrition support and cancer care. The late Dr John Daly opened the presentation with a moving tribute to Dr Dudrick's life and then spoke about the impact of nutrition support on surgical care and outcomes for cancer patients. Dr Pimiento discussed the role of nutraceuticals for cancer chemoprevention, and the level 1 clinical evidence surrounding this topic. Dr Kraemer explored the role of exercise physiology for optimal nutrient utilization and the overlap between targeted physical activity and nutrition support to obtain better outcomes on the cancer population. The symposium was closed by Dr Stephen Hursting, who discussed the impact of obesity in the soaring cancer rates and its relationship with clinical outcomes. In this article, we cover the presentations by Drs Pimiento and Kraemer.

Exercise training partially rescues impaired mucosal associated invariant t-cell mobilization in breast cancer survivors compared to healthy older women

Exercise may attenuate immunosenescence with aging that appears to be accelerated following breast cancer treatment, although limited data on specific cell types exists and acute and chronic exercise have been investigated independently in older adults.

PURPOSE

To determine the mucosal associated invariant T (MAIT) cell response to acute exercise before (PRE) and after (POST) 16 weeks of exercise training in breast cancer survivors (BCS) and healthy older women (CON).

METHODS

Age-matched BCS and CON performed 45 min of intermittent cycling at 60% peak power output wattage. Blood samples were obtained at rest, immediately (0 h) and 1 h after exercise to determine MAIT cell counts, frequency, and intracellular cytokine expression.

RESULTS

At PRE, MAIT cell counts were greater in CON (137%) than BCS at 0 h (46%, p < 0.001), with increased MAIT cell frequency in CON but not BCS. TNFα⁺ and IFNγ⁺ MAIT cell counts increased at 0 h by ~120% in CON (p < 0.001), while BCS counts and frequencies were unchanged. Similar deficits were observed in CD3⁺ and CD3⁺ CD8⁺ cells. At POST, exercise-induced mobilization and egress of MAIT cell counts and frequency showed trends towards improvement in BCS that approached levels in CON. Independent of group, TNFα frequency trended to improve (p = 0.053).

CONCLUSIONS

MAIT mobilization in older BCS following acute exercise was attenuated; however, exercise training may partially rescue these initial deficits, including greater sensitivity to mitogenic stimulation. Using acute exercise before and after interventions provides a unique approach to identify age- and cancer-related immuno-dysfunction that is less apparent at rest.

Identification of lncRNA Signature Associated With Pan-Cancer Prognosis

Long noncoding RNAs (lncRNAs) have emerged as potential prognostic markers in various human cancers as they participate in many malignant behaviors. However, the value of lncRNAs as prognostic markers among diverse human cancers is still under investigation, and a systematic signature based on these transcripts that related to pan-cancer prognosis has yet to be reported. In this study, we proposed a framework to incorporate statistical power, biological rationale, and machine learning models for pan-cancer prognosis analysis. The framework identified a 5-lncRNA signature (ENSG00000206567, PCAT29, ENSG00000257989, LOC388282, and LINC00339) from TCGA training studies (n = 1,878). The identified lncRNAs are significantly associated (all P ≤ 1.48E-11) with overall survival (OS) of the TCGA cohort (n = 4,231). The signature stratified the cohort into low- and high-risk groups with significantly distinct survival outcomes (median OS of 9.84 years versus 4.37 years, log-rank P = 1.48E-38) and achieved a time-dependent ROC/AUC of 0.66 at 5 years. After routine clinical factors involved, the signature demonstrated better performance for long-term prognostic estimation (AUC of 0.72). Moreover, the signature was further evaluated on two independent external cohorts (TARGET, n = 1,122; CPTAC, n = 391; National Cancer Institute) which yielded similar prognostic values (AUC of 0.60 and 0.75; log-rank P = 8.6E-09 and P = 2.7E-06). An indexing system was developed to map the 5-lncRNA signature to prognoses of pan-cancer patients. In silico functional analysis indicated that the lncRNAs are associated with common biological processes driving human cancers. The five lncRNAs, especially ENSG00000206567, ENSG00000257989 and LOC388282 that never reported before, may serve as viable molecular targets common among diverse cancers.

Natural Killer Cell Mobilization in Breast and Prostate Cancer Survivors: The Implications of Altered Stress Hormones Following Acute Exercise

Natural killer (NK) cells from the innate immune system are integral to overall immunity and also in managing the tumor burden during cancer. Breast (BCa) and prostate cancer (PCa) are the most common tumors in U.S. adults. Both BCa and PCa are frequently treated with hormone suppression therapies that are associated with numerous adverse effects including direct effects on the immune system. Regular exercise is recommended for cancer survivors to reduce side effects and improve quality of life. Acute exercise is a potent stimulus for NK cells in healthy individuals with current evidence indicating that NK mobilization in individuals with BCa and PCa is comparable. NK cell mobilization results from elevations in shear stress and catecholamine levels. Despite a normal NK cell response to exercise, increases in epinephrine are attenuated in BCa and PCa. The significance of this potential discrepancy still needs to be determined. However, alterations in adrenal hormone signaling are hypothesized to be due to chronic stress during cancer treatment. Additional compensatory factors induced by exercise are reviewed along with recommendations on standardized approaches to be used in exercise immunology studies involving oncology populations.

Effects of Regular Physical Activity on the Immune System, Vaccination and Risk of Community-Acquired Infectious Disease in the General Population: Systematic Review and Meta-Analysis

Background

Regular physical activity is the prime modality for the prevention of numerous non-communicable diseases and has also been advocated for resilience against COVID-19 and other infectious diseases. However, there is currently no systematic and quantitative evidence synthesis of the association between physical activity and the strength of the immune system.

Objective

To examine the association between habitual physical activity and (1) the risk of community-acquired infectious disease, (2) laboratory‐assessed immune parameters, and (3) immune response to vaccination.

Methods

We conducted a systemic review and meta-analysis according to PRISMA guidelines. We searched seven databases (MEDLINE, Embase, Cochrane CENTRAL, Web of Science, CINAHL, PsycINFO, and SportDiscus) up to April 2020 for randomised controlled trials and prospective observational studies were included if they compared groups of adults with different levels of physical activity and reported immune system cell count, the concentration of antibody, risk of clinically diagnosed infections, risk of hospitalisation and mortality due to infectious disease. Studies involving elite athletes were excluded. The quality of the selected studies was critically examined following the Cochrane guidelines using ROB2 and ROBINS_E. Data were pooled using an inverse variance random-effects model.

Results

Higher level of habitual physical activity is associated with a 31% risk reduction (hazard ratio 0.69, 95% CI 0.61–0.78, 6 studies, N = 557,487 individuals) of community-acquired infectious disease and 37% risk reduction (hazard ratio 0.64, 95% CI 0.59–0.70, 4 studies, N = 422,813 individuals) of infectious disease mortality. Physical activity interventions resulted in increased CD4 cell counts (32 cells/µL, 95% CI 7–56 cells/µL, 24 studies, N = 1112 individuals) and salivary immunoglobulin IgA concentration (standardised mean difference 0.756, 95% CI 0.146–1.365, 7 studies, N = 435 individuals) and decreased neutrophil counts (704 cells/µL, 95% CI 68–1340, 6 studies, N = 704 individuals) compared to controls. Antibody concentration after vaccination is higher with an adjunct physical activity programme (standardised mean difference 0.142, 95% CI 0.021–0.262, 6 studies, N = 497 individuals).

Conclusion

Regular, moderate to vigorous physical activity is associated with reduced risk of community-acquired infectious diseases and infectious disease mortality, enhances the first line of defence of the immune system, and increases the potency of vaccination.

Protocol registration

The original protocol was prospectively registered with PROSPERO (CRD42020178825).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40279-021-01466-1.

[Significance of evaluation of CD69 expression by peripheral blood lymphocytes for predicting pregnancy outcome in women with recurrent pregnancy loss]

The aim of this work was to characterize phenotypically peripheral blood T- and NK lymphocytes expressing an early marker of activation, CD69, and assess the significance of CD69 expression for predicting pregnancy outcome in women with idiopathic reccurent pregnancy loss (IRP) before and after immunocytotherapy (ICT). The study group consisted of 36 patients with IRP who became pregnant after pre-gestational allimmunization, in 30 patients the pregnancy was prolonged to the full term and ended with the birth of a viable baby, in 6 - it was terminated before 12 weeks of gestation. In the control group, 15 fertile women outside pregnancy and 11 women at 12 weeks of physiological pregnancy were examined. Assessment of the CD69 expression in women with prolonged pregnancy revealed the absence of significant differences with the control group in the content and proportion of activated lymphocytes (CD69+). In women with aborted pregnancy after pre-gestational ICT, an increase in the number of almost all analyzed lymphocyte subpopulations responding to the activation stimulus, with a clear tendency to increase the proportion of activated T- but not NK-lymphocytes was found. At 5-6 weeks, the proportion of activated lymphocytes among a subpopulation of cytotoxic T-lymphocytes (CD3+CD8+/CD3+CD8+CD69+) in these women was significantly higher than in women with prolonged pregnancy, which confirms the leading role of effector cytotoxic T-lymphocytes in rejection reactions. Thus, the studies showed the promise of evaluating the expression of the early activation marker CD69 as an additional laboratory criterion for the personable appointment of immunocytotherapy to women with a common reccurent pregnancy loss.

Physical Activity and Liver Cancer Risk: A Systematic Review and Meta-analyses

OBJECTIVE

Liver cancer is the second most common cause of death from cancer. Physical activity (PA) was found to be associated with lower risks of several types of cancer. However, the association between PA and the risk of liver cancer is still inconclusive. This systematic review and meta-analysis was aiming to summarize the association between PA and liver cancer risk.

METHODS

Literatures related were identified by searching PubMed, EMBASE, and Chinese Biomedical literature database from 1965 to 2017 without language limitation. Meta-analyses were performed using random effect model.

RESULTS

A total of 5 cohort studies involving 2 513 975 subjects were identified. The pooled relative risk of leisure-time PA with liver cancer risk was 0.92 [95% confidence interval (CI), 0.84-1.01]. There is no significant association between leisure-time PA and liver cancer risk. However, leisure-time PA significantly reduced liver cancer risk in never smokers. The pooled hazard ratio of daily total PA with liver cancer risk was 0.75 (95% CI, 0.66-0.86).

CONCLUSIONS

Daily total PA significantly reduces liver cancer risk, whereas leisure-time PA significantly reduces liver cancer risk only in never smokers.

Pre-post analysis of a social capital-based exercise adherence intervention for breast cancer survivors with moderate fatigue: a randomized controlled trial

PURPOSE

This study assessed the effectiveness of the Better Life After Cancer: Energy, Strength, and Support (BLESS) program, a 12-week social capital-based exercise adherence program for breast cancer survivors (BCS), regarding cancer-related fatigue (CRF), quality of life (QOL), physical activity, and psychosocial characteristics.

METHODS

Forty-eight BCS with moderate or high (≥ 4) CRF participated in this randomized control trial (intervention group n = 23, control group n = 25). The intervention group participated in small group sessions to activate social capital while targeting CRF in supervised physical exercises supplemented by home-based physical exercises. The control group was only given written information on exercise. A questionnaire was used to assess CRF, QOL, physical activity, depression, anxiety, sleep quality, and social capital.

RESULTS

The majority of participants had undergone surgery less than 2 years ago. After participating in BLESS, the CRF behavioral/severity domain significantly decreased (t = 2.642, p = 0.011) and physical activity significantly increased (t = - 2.049, p = 0.046) in the intervention group, in comparison with the control group; there were no significant post-intervention differences in the control group. Both groups showed improvements in sleep quality, depression, anxiety, and QOL.

CONCLUSION

The BLESS program decreased behavioral/severity in the CRF and increased physical activity after 12 weeks among BCS. Future research needs to evaluate whether the promising results on physical activity and behavioral fatigue observed in the short term will persist over time. Also, longer-term effects should be examined.

Physical Activity and Breast Cancer Prevention: Possible Role of Immune Mediators

There is strong evidence that physical activity (PA) reduces risk, recurrence, and mortality from breast cancer. Emerging data suggest that PA induces changes in inflammatory and immune mediators that may contribute to beneficial effects on breast cancer outcomes. Thus, the goal of this review was to evaluate the evidence linking the protective benefit of PA to modulation of immune responses in breast cancer. A literature search was conducted to identify studies that evaluated the impact of PA on tumor and immune outcomes in breast cancer patients and in mammary tumor models. Nineteen studies investigated the effect of PA interventions on cancer immune outcomes using preclinical breast cancer models. Tumor growth was reduced in 11 studies, unchanged in three studies, and increased in one study. Spontaneous metastasis was reduced in two studies and survival was improved in four studies. Frequently assessed immune outcomes include splenic cell number and function, circulating inflammatory cytokines, and intratumoral immune cells and inflammatory markers. Circulating inflammatory cytokine responses were heterogeneous in preclinical models. Within the tumor microenvironment (TME), several studies documented a change in the infiltration of immune cells with an increase in effector cells and a reduction in immune suppressive cells. Twenty-three studies investigated the effect of PA interventions on immune outcomes in breast cancer patients. Thirteen studies used aerobic PA interventions and 10 studies used a combination of aerobic and resistance exercise interventions. Cycling and treadmill activities were the most commonly used PA modalities. Circulating immune cells and inflammatory cytokines were the most frequently assessed immune outcomes in the clinical studies. Among the 19 studies that evaluated a PA intervention during the post treatment period, 10 reported a reduction in the levels of at least one inflammatory cytokine. No inflammatory cytokines were quantified in the three studies that evaluated a PA intervention during treatment with chemotherapy. Immune outcomes within the tumor were assessed in only one study performing a PA intervention prior to surgery. Results from preclinical and clinical studies suggest that PA exerts heterogeneous effects on inflammatory cytokines, but may alter the gene expression profile and immune infiltrates in the tumor which may result in a reduction in immunosuppressive factors. However, additional studies are needed to better understand the effect of PA on immune outcomes in the TME.

Relationships between Exercise Modality and Activity Restriction, Quality of Life, and Hematopoietic Profile in Korean Breast Cancer Survivors

This study aimed to examine the relationships between activity restriction, quality of life (QoL), and hematopoietic profile in breast cancer survivors according to exercise modality. The subjects in this study were 187 female breast cancer survivors among a total of 32,631 participants in the Korea National Health and Nutrition Examination Survey, which was conducted from 2016 to 2018. The selected subjects participated in a questionnaire survey and blood analysis. A cross-analysis was conducted to determine the relationship between participation in various modality of exercise (e.g., aerobic exercise, resistance exercise, walking exercise). The phi coefficients or Cramer’s V value for activity restriction and QoL were calculated; an independent t-test was conducted to evaluate the differences between hematopoietic profiles based on the modality of exercise. Statistically significant correlations were seen between obesity and aerobic exercise and walking frequency, as well as between diabetes and aerobic exercise and activity restriction. With respect to QoL, there was a statistically significant correlation between participation in aerobic exercise and exercise ability, participation in aerobic exercise and anxiety/depression, participation in resistance exercise and subjective health status, participation in resistance exercise and exercise ability, and participation in weekly walking exercise and self-care ability. Regarding hemodynamic changes, red blood cells increased significantly in breast cancer survivors who participated in weekly resistance exercise compared to in those who did not. In conclusion, exercise participation had a positive effect on activity restriction, QoL, and hematopoietic profile in breast cancer survivors; in particular, some modalities of aerobic exercise were more effective.

Application of physical exercise therapies in breast cancer survivors and their effects on the inflammatory profile: A narrative review

BACKGROUND

One of the adverse effects of cancer treatments is the exacerbation of inflammation, which generates numerous limitations and contributes to the development of several comorbidities and the recurrence of cancer itself. Physical exercise (PE) has been proposed as an efficient complementary strategy to combat the inflammatory effects of oncological treatments and to prevent the development of comorbidities, but its adequate application in breast cancer survivors (BCS) requires the establishment of consensuses and practical recommendations.

OBJECTIVE

This study aimed to review the randomized controlled trials that evaluated the influence of PE in the inflammatory profile of BCS.

METHODS

The search for articles published between 1999 and 2020 was done in PsycINFO, PubMed, Cochrane, Science Direct, and Scopus databases.

RESULTS

Current knowledge reveals the effectiveness of PE in the functional independence and health of BCS. Evidence of the capacity of PE to improve the inflammatory profile and the immune response in BCS has also been described. However, the heterogeneity of the studies regarding structural training variables, types of exercise, stages of intervention, and severity of the disease, still do not allow the establishment of precise guidelines for the prescription and progression of exercise to improve the inflammatory process in BCS.

DISCUSSION

. This review suggests a possible strategy to be used in the assessment, training prescription, and rehabilitation of BCS, to support the development of new studies and the work of exercise professionals in the prescription and application of physical training to improve health and inflammatory status in BCS.

Resistance training in breast cancer patients undergoing primary treatment: a systematic review and meta-regression of exercise dosage

BACKGROUND

Exercise is recognised as an adjunct therapy for breast cancer patients; however, little is known about the resistance training dose-response. We conducted a systematic review and meta-regression to examine the resistance training dose-response (i.e., volume and intensity) in breast cancer patients undergoing primary treatment.

METHODS

Searches in MEDLINE, CINAHL, and SPORTDiscus were conducted for studies published up to November 2019. Experimental studies that evaluated resistance-based exercise interventions in women with breast cancer undergoing primary treatment were included. Information about resistance training components, average change and change per week, as well as standardised mean difference were extracted, and used for meta-regression analysis. Outcome measures were upper and lower body muscle strength and body composition.

RESULTS

10 trials were included in the systematic review and 4 trials in the dose-response analysis. Resistance training weekly prescribed volume was inversely associated with increases in upper and lower body muscle strength (r² = 98.1-100%; p = 0.009), although there was no relationship between resistance training intensity and strength gains. There was insufficient data for the dose-response analysis of body mass index, percent body fat, and lean mass.

CONCLUSION

Low volume resistance training might be a suitable exercise recommendation for breast cancer patients undergoing primary treatment producing superior benefits for muscle strength compared to higher volume training, regardless of the training intensity. Low volume resistance training may provide a conservative and appropriate approach for breast cancer patients, allowing gradual progression and modification throughout the exercise program.

The PAPHIO study protocol: a randomised controlled trial with a 2 x 2 crossover design of physical activity adherence, psychological health and immunological outcomes in breast cancer survivors

BACKGROUND

The PAPHIO study; a randomized controlled trial with 2X2 crossover design will implement a self-directed physical activity program in which participants will engage in self-monitoring and receive motivational interviewing to enhance physical activity adherence. The study aims to determine the effects of 24 weeks self-directed activity combined with motivational interviewing (MI) on (i) psychological health, (ii) quality of life (QoL) and (iii) immune function in female breast cancer survivors.

METHODS

The study will recruit 64 female breast cancer survivors within 3 years of diagnosis and at least 6 months post primary treatments at Western Health Sunshine Hospital, Melbourne, Australia. They will be randomly allocated to immediate intervention (IIG group) or delayed intervention groups (DIG group) in a 1:1 ratio. All participants will be given a wearable device (Fitbit Alta HR) and undertake self-directed physical activity for 24 weeks and will receive MI for 12 weeks (IIG; during week 0 to week 12 and DIG; during week 13 to week 24). Participants' daily step count and the changes of immune cell functionality will be assessed at the beginning (week 1: T1), week 12 (T2) and week 24 (T3) of the program. Physical activity adherence will be assessed at T2 and T3. Participants will also complete four questionnaires assessing exercise self-regulation (BREQ2), exercise barrier and task self-efficacy, mental health (DASS-21) and QoL (FACT-B) at three time points (T1 to T3). Linear-mixed models will be used to assess the relationship between physical activity volume by step counting and mental health (DASS-21), QoL (FACT-B), immune biomarkers, self-regulation (BREQ2) and self-efficacy at T1, T2 and T3;between 2 groups.

DISCUSSION

We expect this physical activity intervention to be acceptable and beneficial to the participants in terms of psychological and immunological well-being with the potential outcomes to be implemented more widely at relatively low cost to these or other patient populations.

TRIAL REGISTRATION

Australian New Zealand Clinical trials Registry- ACTRN12619001271190. Prospectively registered on 13 September 2019.

How Many Steps Per Day are Necessary to Prevent Postoperative Complications Following Hepato-Pancreato-Biliary Surgeries for Malignancy?

PURPOSE

The current study was designed to investigate the association between the average preoperative physical activity and postoperative outcomes in patients undergoing surgeries for hepato-pancreato-biliary (HPB) malignancy.

METHODS

Patients who were scheduled to undergo open abdominal surgeries for HPB malignancies (major hepatectomy, pancreatoduodenectomy, or hepato-pancreatoduodenectomy) between 2016 and 2017 were included. The average steps per day were recorded by a pedometer and calculated for each patient during the preoperative waiting period. Physical activity levels were classified according to the average number of daily steps as poor (< 5000 steps/day) and good (≥ 5000 steps/day).

RESULTS

Of the 105 eligible patients, 78 met the inclusion criteria. The median number of steps per day was 6174. There were 48 patients (62%) with good physical activity and 30 patients (38%) with poor physical activity. Patients with poor physical activity revealed a significantly higher rate of major complications with Clavien grade ≥ 3 (63% vs. 35%, p = 0.016), a higher rate of infectious complications (53% vs. 23%, p = 0.006), and a longer postoperative hospital stay (median, 30 vs. 21 days, p < 0.001) compared with those with good physical activity. After a multivariate analysis, poor physical activity was identified as an independent risk factor for the development of major complications (odds ratio, 2.842, p = 0.042) and infectious complications (odds ratio, 3.844, p = 0.007).

CONCLUSIONS

The current study demonstrated that preoperative physical activity levels are associated with the incidence of major postoperative complications following HPB surgery for malignancy.

Moderate physical exercise improves lymphocyte function in melanoma-bearing mice on a high-fat diet

Background

Obesity can lead to a chronic systemic inflammatory state that increases the risk of cancer development. Therefore, this study aimed to evaluate the alterations in tumor non-infiltrated lymphocytes function and melanoma growth in animals maintained on a high-fat diet and/or moderate physical exercise program in a murine model of melanoma.

Methods

Female mice were randomly divided into eight groups: 1) normolipidic control (N), 2) normolipidic + melanoma (NM), 3) high-fat control (H), 4) high-fat + melanoma (HM), 5) normolipidic control + physical exercise (NE), 6) normolipidic melanoma + physical exercise (NEM), 7) high-fat control + physical exercise (HE), and 8) high-fat melanoma + physical exercise (HEM). After 8 weeks of diet treatment and/or moderate physical exercise protocol, melanoma was initiated by explanting B16F10 cells into one-half of the animals.

Results

Animals fed a high-fat diet presented high-energy consumption (30%) and body weight gain (H and HE vs N and NE, 37%; HM and HEM vs NM and NEM, 73%, respectively), whether or not they carried melanoma explants. Although the tumor growth rate was higher in animals from the HM group than in animals from any other sedentary group, it was reduced by the addition of a physical exercise regimen. We also observed an increase in stimulated peripheral lymphocyte proliferation and a decrease in the T-helper 1 response in the HEM group.

Conclusions

The results of the present study support the hypothesis that altering function of tumor non-infiltrated lymphocytes via exercise-related mechanisms can slow melanoma progression, indicating that the incorporation of a regular practice of moderate-intensity exercises can be a potential strategy for current therapeutic regimens in treating advanced melanoma.

Can Exercise-Induced Modulation of the Tumor Physiologic Microenvironment Improve Antitumor Immunity?

The immune system plays an important role in controlling cancer growth. However, cancers evolve to evade immune detection. Immune tolerance and active immune suppression results in unchecked cancer growth and progression. A major contributor to immune tolerance is the tumor physiologic microenvironment, which includes hypoxia, hypoglucosis, lactosis, and reduced pH. Preclinical and human studies suggest that exercise elicits mobilization of leukocytes into circulation (also known as "exercise-induced leukocytosis"), especially cytotoxic T cells and natural killer cells. However, the tumor physiologic microenvironment presents a significant barrier for these cells to enter the tumor and, once there, properly function. We hypothesize that the effect of exercise on the immune system's ability to control cancer growth is linked to how exercise affects the tumor physiologic microenvironment. Normalization of the microenvironment by exercise may promote more efficient innate and adaptive immunity within the tumor. This review summarizes the current literature supporting this hypothesis.

Physical Activity, Weight Control, and Biomarkers of Prognosis and Survival among Breast Cancer Survivors

Physical inactivity and obesity may increase risk of poor prognosis in breast cancer through effects on insulin or insulin-like growth factors or their binding proteins, insulin resistance, glucose metabolism, sex hormones, leptin and other adipokines, immunologic or inflammatory factors, oxidative stress, and Deoxyribonucleic acid (DNA) damage or repair capacity. The present review is based upon bibliographic searches in PubMed and relevant search terms. Articles published in English from January 1, 1980 through October 1, 2018 were identified using the following MeSH search terms and Boolean algebra commands: breast cancer survivors AND (insulin-like growth factor OR insulin resistance OR glucose metabolism OR sex hormones OR leptin OR adipokines OR immunologic OR inflammatory factors OR oxidative stress OR DNA repair capacity). After screening the abstracts or full texts of these articles and reviewing the references of previous review articles, a total of 66 studies met the eligibility criteria. Based upon published studies, it is difficult to determine the type or dose of exercise that affects inflammatory markers among breast cancer survivors. The optimal type of exercise, dose, and timing of physical activity needed to improve the inflammatory profile following a breast cancer diagnosis is unknown. Studies have used a range of physical activity types including aerobic, resistance training, yoga, and Tai Chi. A further issue is that existing studies of physical activity and biomarkers have included a range of disease stages. There is a need for a better understanding of the biological pathways through which physical activity and weight management increase survival in order to design targeted weight loss and exercise interventions for breast cancer survivors.

A Systematic Review and Meta-Analysis of the Safety, Feasibility, and Effect of Exercise in Women With Stage II+ Breast Cancer

OBJECTIVE

To systematically evaluate the safety, feasibility, and effect of exercise among women with stage II+ breast cancer.

DATA SOURCES

CINAHL, Cochrane, Ebscohost, MEDLINE, Pubmed, ProQuest Health and Medical Complete, ProQuest Nursing and Allied Health Source, Science Direct and SPORTDiscus were searched for articles published before March 1, 2017.

STUDY SELECTION

Randomized, controlled, exercise trials involving at least 50% of women diagnosed with stage II+ breast cancer were included.

DATA EXTRACTION

Risk of bias was assessed and adverse event severity was classified using the Common Terminology Criteria. Feasibility was evaluated by computing median (range) recruitment, withdrawal, and adherence rates. Meta-analyses were performed to evaluate exercise safety and effects on health outcomes only. The influence of intervention characteristics (mode, supervision, duration and timing) on exercise outcomes were also explored.

DATA SYNTHESIS

There were no differences in adverse events between exercise and usual care (risk difference: <0.01 ([95% CI: -0.01, 0.01], P=0.38). Median recruitment rate was 56% (1%-96%), withdrawal rate was 10% (0%-41%) and adherence rate was 82% (44%-99%). Safety and feasibility outcomes were similar, irrespective of exercise mode, supervision, duration, or timing. Effects of exercise for quality of life, fitness, fatigue, strength, anxiety, depression, body mass index and waist circumference compared with usual care were significant (standardized mean difference range: 0.17-0.77, P<0.05).

CONCLUSION

The findings support the safety, feasibility, and effects of exercise for those with stage II+ breast cancer, suggesting that national and international exercise guidelines appear generalizable to women with local, regional, and distant breast cancer.

Physical Activity, Exercise and Breast Cancer - What Is the Evidence for Rehabilitation, Aftercare, and Survival? A Review

The current scientific field of exercise interventions in breast cancer is very large. Rehabilitation focuses on restoring or improving quality of life and thus on independence and participation in life. Hence, it is important to investigate exercise interventions in the setting of rehabilitation and aftercare. It is also necessary to determine the influence of physical activity or exercise therapy on the prevention of recurrence and mortality as well as on certain side effects of the disease and its medical treatment in rehabilitation. Physical activity in rehabilitation and aftercare is feasible and safe and can be used for various purposes. Against the background of reduced fatigue, chemotherapy-induced peripheral neuropathy, cancer-related cognitive impairment, arthralgia, lymphedema, recurrence, and mortality, as well as improved quality of life, different methodological approaches and evidence can be seen. Although the overall data availability has increased, there are gaps in study documentation as well as inadequate verification of scientific approaches in rehabilitation clinics and in everyday life.

Influence of physical activity on the immune system in breast cancer patients during chemotherapy

PURPOSE

Physical activity can impact the immune system in different ways, e.g. by alteration of the humoral and cellular immune response. Physical activity at medium intensity enhances numbers of cytotoxic T cells, NK cells and macrophages in healthy people. The aim of this study was to compare the effects of endurance and resistance training on the immune system in breast cancer patients during adjuvant chemotherapy.

METHODS

In a prospective, controlled and randomized intervention exploratory trial, 12-week supervised endurance or resistance training were compared with usual care twice a week. Endpoints were the absolute numbers of the immune cells such as CD3+ T lymphocytes including CD4+- and CD8+, αβ T cells, γδT cells, CD3-/CD16+/56+ NK cells and CD19+ B cells, before and after 12 weeks of treatment. Cell numbers were analyzed using fluorescence-activated cell sorting.

RESULTS

Despite different physical interventions in all groups immune cell count decreased in CD3 T cells including TCR αβ and CD4 T cells, NK cells and CD19 B cells 12 weeks after initiation of chemotherapy and start of the physical intervention program, while the reduction of γδ T cells and CD8 T cells is less prominent in the RT and UC group.

CONCLUSION

Chemotherapy led to a decrease in nearly all measured immune cells. In this study, physical intervention with endurance or resistance training did not suppress cellular immunity any further. Larger multicenter trials are needed to evaluate the exact impact of sports intervention on immune cell subpopulations.

The Impact of Exercise Training on Breast Cancer

BACKGROUND/AIM

Physical exercise is increasingly considered by many authors to be a factor reducing the risk of cancer development and premature cancer-related death. Data indicate higher cure rates and longer times of survival in cancer patients who regularly exercise.

MATERIALS AND METHODS

A total of 50 female Sprague-Dawley rats were used in the experiment. Animals at 1 month of age were intraperitoneally injected with N-methyl-N-nitrosourea. Three months following drug administration, rats underwent supervised physical training. The animals were divided into four groups: control untrained group and 3 groups trained with different intensities - i.e. low, moderate and high. Routine histopathological examination of tumors was performed and mitotic activity was assessed by immunohistochemical expression of the Ki-67 antigen.

RESULTS

Ki-67 antigen expression was observed in all analyzed tumors. The increase in Ki-67 antigen expression correlated positively with the increase in training intensity.

CONCLUSION

It can be assumed that low-intensity physical training is safe for patients with breast cancer. However, moderate- and high-intensity training may induce tumor cell proliferation worsening patients' prognosis.

Physical activity for women with breast cancer after adjuvant therapy

BACKGROUND

Women with a diagnosis of breast cancer may experience short- and long-term disease and treatment-related adverse physiological and psychosocial outcomes. These outcomes can negatively impact prognosis, health-related quality of life (HRQoL), and psychosocial and physical function. Physical activity may help to improve prognosis and may alleviate the adverse effects of adjuvant therapy.

OBJECTIVES

To assess effects of physical activity interventions after adjuvant therapy for women with breast cancer.

SEARCH METHODS

We searched the Cochrane Breast Cancer Group (CBCG) Specialised Registry, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), the Physiotherapy Evidence Database (PEDro), SPORTDiscus, PsycINFO, ClinicalTrials.gov, and the World Health Organization (WHO) International Clinical Trials Registry Platform, on 18 September 2015. We also searched OpenGrey and Healthcare Management Information Consortium databases.

SELECTION CRITERIA

We searched for randomised and quasi-randomised trials comparing physical activity interventions versus control (e.g. usual or standard care, no physical activity, no exercise, attention control, placebo) after adjuvant therapy (i.e. after completion of chemotherapy and/or radiation therapy, but not hormone therapy) in women with breast cancer.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risk of bias, and extracted data. We contacted trial authors to ask for additional information when needed. We calculated an overall effect size with 95% confidence intervals (CIs) for each outcome and used GRADE to assess the quality of evidence for the most important outcomes.

MAIN RESULTS

We included 63 trials that randomised 5761 women to a physical activity intervention (n = 3239) or to a control (n = 2524). The duration of interventions ranged from 4 to 24 months, with most lasting 8 or 12 weeks (37 studies). Twenty-eight studies included aerobic exercise only, 21 involved aerobic exercise and resistance training, and seven used resistance training only. Thirty studies described the comparison group as usual or standard care, no intervention, or control. One-fifth of studies reported at least 20% intervention attrition and the average physical activity adherence was approximately 77%.No data were available on effects of physical activity on breast cancer-related and all-cause mortality, or on breast cancer recurrence. Analysis of immediately postintervention follow-up values and change from baseline to end of intervention scores revealed that physical activity interventions resulted in significant small-to-moderate improvements in HRQoL (standardised mean difference (SMD) 0.39, 95% CI 0.21 to 0.57, 22 studies, 1996 women; SMD 0.78, 95% CI 0.39 to 1.17, 14 studies, 1459 women, respectively; low-quality evidence), emotional function (SMD 0.21, 95% CI 0.10 to 0.32, 26 studies, 2102 women, moderate-quality evidence; SMD 0.31, 95% CI 0.09 to 0.53, 15 studies, 1579 women, respectively; low-quality evidence), perceived physical function (SMD 0.33, 95% CI 0.18 to 0.49, 25 studies, 2129 women; SMD 0.60, 95% CI 0.23 to 0.97, 13 studies, 1433 women, respectively; moderate-quality evidence), anxiety (SMD -0.57, 95% CI -0.95 to -0.19, 7 studies, 326 women; SMD -0.37, 95% CI -0.63 to -0.12, 4 studies, 235 women, respectively; low-quality evidence), and cardiorespiratory fitness (SMD 0.44, 95% CI 0.30 to 0.58, 23 studies, 1265 women, moderate-quality evidence; SMD 0.83, 95% CI 0.40 to 1.27, 9 studies, 863 women, respectively; very low-quality evidence).Investigators reported few minor adverse events.Small improvements in physical activity interventions were sustained for three months or longer postintervention in fatigue (SMD -0.43, 95% CI -0.60 to -0.26; SMD -0.47, 95% CI -0.84 to -0.11, respectively), cardiorespiratory fitness (SMD 0.36, 95% CI 0.03 to 0.69; SMD 0.42, 95% CI 0.05 to 0.79, respectively), and self-reported physical activity (SMD 0.44, 95% CI 0.17 to 0.72; SMD 0.51, 95% CI 0.08 to 0.93, respectively) for both follow-up values and change from baseline scores.However, evidence of heterogeneity across trials was due to variation in intervention components (i.e. mode, frequency, intensity, duration of intervention and sessions) and measures used to assess outcomes. All trials reviewed were at high risk of performance bias, and most were also at high risk of detection, attrition, and selection bias. In light of the aforementioned issues, we determined that the evidence was of very low, low, or moderate quality.

AUTHORS' CONCLUSIONS

No conclusions regarding breast cancer-related and all-cause mortality or breast cancer recurrence were possible. However, physical activity interventions may have small-to-moderate beneficial effects on HRQoL, and on emotional or perceived physical and social function, anxiety, cardiorespiratory fitness, and self-reported and objectively measured physical activity. The positive results reported in the current review must be interpreted cautiously owing to very low-to-moderate quality of evidence, heterogeneity of interventions and outcome measures, imprecision of some estimates, and risk of bias in many trials. Future studies with low risk of bias are required to determine the optimal combination of physical activity modes, frequencies, intensities, and durations needed to improve specific outcomes among women who have undergone adjuvant therapy.

Breast Cancer Survivors, Common Markers of Inflammation, and Exercise: A Narrative Review

Exercise may help positively improve inflammatory marker levels, therefore promoting better outcomes in breast cancer survivors. This narrative review is intended to provide an overview between inflammation and breast cancer, in addition to the effects exercise may have on common inflammatory markers that have been examined in both healthy populations and breast cancer survivors throughout the literature. The inconsistencies and gaps in the literature addressed may be important for future research to further understand the relationship between exercise and inflammation, as well as the underlying biological mechanisms that are responsible for these changes. For the purpose of organization, this review is structured into the following sections: (1) Breast Cancer Facts, Treatment-Related Side Effects, and General Exercise Benefits; (2) Effects of Exercise on Markers of Inflammation in Cancer-Free Populations; (3) Cancer and Markers of Inflammation; (4) Effects of Exercise on Markers of Inflammation in Breast Cancer Survivors; and (5) Conclusions.

Adipose tissue inflammation in breast cancer survivors: effects of a 16-week combined aerobic and resistance exercise training intervention

PURPOSE

Obesity is a leading modifiable contributor to breast cancer mortality due to its association with increased recurrence and decreased overall survival rate. Obesity stimulates cancer progression through chronic, low-grade inflammation in white adipose tissue, leading to accumulation of adipose tissue macrophages (ATMs), in particular, the pro-inflammatory M1 phenotype macrophage. Exercise has been shown to reduce M1 ATMs and increase the more anti-inflammatory M2 ATMs in obese adults. The purpose of this study was to determine whether a 16-week exercise intervention would positively alter ATM phenotype in obese postmenopausal breast cancer survivors.

METHODS

Twenty obese postmenopausal breast cancer survivors were randomized to a 16-week aerobic and resistance exercise (EX) intervention or delayed intervention control (CON). The EX group participated in 16 weeks of supervised exercise sessions 3 times/week. Participants provided fasting blood, dual-energy X-ray absorptiometry (DXA), and superficial subcutaneous abdominal adipose tissue biopsies at baseline and following the 16-week study period.

RESULTS

EX participants experienced significant improvements in body composition, cardiometabolic biomarkers, and systemic inflammation (all p < 0.03 vs. CON). Adipose tissue from EX participants showed a significant decrease in ATM M1 (p < 0.001), an increase in ATM M2 (p < 0.001), increased adipose tissue secretion of anti-inflammatory cytokines such as adiponectin, and decreased secretion of the pro-inflammatory cytokines IL-6 and TNF- α (all p < 0.055).

CONCLUSIONS

A 16-week aerobic and resistance exercise intervention attenuates adipose tissue inflammation in obese postmenopausal breast cancer survivors. Future large randomized trials are warranted to investigate the impact of exercise-induced reductions in adipose tissue inflammation and breast cancer recurrence.

Graded versus Intermittent Exercise Effects on Lymphocytes in Chronic Fatigue Syndrome

PURPOSE

There is increasing evidence of immune system dysfunction in chronic fatigue syndrome (CFS), but little is known of the regular exercise effects on immune cell parameters. This pilot study investigated the effects of graded and intermittent exercise on CD4 lymphocyte subset counts and activation compared with usual care.

METHODS

Twenty-four CFS patients (50.2 ± 10 yr) were randomized to graded exercise (GE), intermittent exercise (IE), or usual care (UC) groups; 18 sedentary non-CFS participants (50.6 ± 10 yr) were controls (CTL) for blood and immunological comparisons. Outcome measures were pre- and postintervention flow cytometric analyses of circulating lymphocyte subset cell counts; expression of CD3, CD4, CD25, and CD134; full blood counts; and V˙O2peak.

RESULTS

Preintervention, CD3 cell counts, and expression of CD4, CD25, CD134, and CD4CD25CD134 were significantly lower in GE, IE, and UC compared with CTL (P < 0.05). Total lymphocyte concentration was significantly lower in GE and IE groups compared with CTL. There were significant postintervention increases in i) expression of CD4 and CD4CD25CD134 for GE and IE, but CD25 and CD134 for IE only; ii) circulating counts of CD3 and CD4 for GE, and CD3, CD4, CD8, CD3CD4CD8, CD3CD16CD56, CD19, and CD45 for IE; iii) neutrophil concentration for GE; and iv) V˙O2peak and elapsed test time for IE and GE, V˙Epeak for IE.

CONCLUSIONS

Twelve weeks of GE and IE training significantly improved CD4 lymphocyte activation and aerobic capacity without exacerbating CFS symptoms. IE may be a more effective exercise modality with regard to enhanced CD4 activation in CFS patients.

The effects of a home-based physical activity intervention on cardiorespiratory fitness in breast cancer survivors; a randomised controlled trial

The aim of this current randomised controlled trial was to evaluate the effects of a home-based physical activity (PA) intervention on cardiorespiratory fitness in breast cancer survivors. Thirty-two post-adjuvant therapy breast cancer survivors (age = 52 ± 10 years; BMI = 27.2 ± 4.4 kg∙m²) were randomised to a six-month home-based PA intervention with face-to-face and telephone PA counselling or usual care. Cardiorespiratory fitness and self-reported PA were assessed at baseline and at six-months. Participants had a mean relative V̇O₂max of 25.3 ± 4.7 ml∙kg^-1∙min^-1, which is categorised as "poor" according to age and gender matched normative values. Magnitude-based inference analyses revealed likely at least small beneficial effects (effect sizes ≥.20) on absolute and relative V̇O₂ max (d = .44 and .40, respectively), and total and moderate PA (d = .73 and .59, respectively) in the intervention compared to the usual care group. We found no likely beneficial improvements in any other outcome. Our home-based PA intervention led to likely beneficial, albeit modest, increases in cardiorespiratory fitness and self-reported PA in breast cancer survivors. This intervention has the potential for widespread implementation and adoption, which could considerably impact on post-treatment recovery in this population.

Rehabilitation and exercise oncology program: translating research into a model of care

INTRODUCTION

The Rehabilitation and Exercise Oncology model of care (ActivOnco) was established to optimize cancer survivorship through exercise prescription and active lifestyle promotion, providing a transition of care from hospital to community. Patients having any cancer diagnosis, stage of disease, and treatment were eligible for evaluation and exercise prescription upon deterioration of performance status. The team of professionals included hospital-based physiotherapists proactively screening for rehabilitation needs, loss of functional independence, and exercise eligibility, plus exercise specialists in a community-based Wellness Centre to provide follow-up or direct access for post-treatment or non-complex patients.

METHODS

From January 2011 to December 2015, the hospital team assessed 1635 patients representing all major cancer sites, and the Wellness Centre team evaluated and prescribed exercise for 1066 participants. Primary interventions provided were education about fatigue management, physical activity promotion, exercise prescription, fracture risk reduction, referral to specialized follow-up services (for example, occupational therapy, lymphedema clinic), and coordination for mobility aids and paratransit services.

RESULTS AND CONCLUSIONS

Implementation of the ActivOnco model of care showed that exercise alone is not a panacea for all functional deterioration associated with the cancer trajectory and its treatment. However, screening to identify rehabilitation needs combined with exercise prescription can effectively improve the quality of survivorship in cancer patients. Program developments are limited by the cost of human resources, lack of hospital-based physical resources, and lack of public funding, all of which significantly limit the scope and development of appropriate services.

Breast cancer and exercise: The role of adiposity and immune markers

Currently, breast cancer accounts for a quarter of all cancers and 15% of cancer-specific deaths amongst females. The global occurrence of breast cancer has increased in the last decade whilst the mortality rate has decreased. Exercise can be beneficial to breast cancer patients through changes in adiposity and immune responses. Even though there is some evidence supporting the improvement of fat metabolism and immune function after an exercise program in breast cancer, randomized controlled studies are limited and require further comprehensive analysis in this population group. Herein, we identify the known effects of exercise programs on adiposity and immunological markers which can improve breast cancer outcomes.

Effects of Exercise on Insulin, IGF Axis, Adipocytokines, and Inflammatory Markers in Breast Cancer Survivors: A Systematic Review and Meta-analysis

Background: Insulin, IGF axis, adiponectin, and inflammatory markers are associated with breast cancer. Given that physical activity improves prognosis of breast cancer survivors, we investigated the effects of exercise on these markers as potential mediators between physical activity and breast cancer.Methods: PubMed, EMBASE, CENTRAL, CINAHL, and SportDiscus were searched up to December 3, 2015, to identify randomized controlled trials (RCT) that investigated the effect of exercise on insulin, IGF axis, and cytokines in breast cancer survivors. Weighted mean difference (WMD) was calculated using either fixed- or random-effects models on the basis of the heterogeneity of the studies.Results: A total of 18 studies involving 681 breast cancer survivors were included, and these numbers were reduced for individual biomarker analyses. We found that exercise significantly reduced fasting insulin levels [WMD, -3.46 μU/mL; 95% confidence interval (CI), -5.97 to -0.95; P = 0.007]. Furthermore, potentially meaningful but statistically nonsignificant changes were observed in insulin resistance (WMD, -0.73; 95% CI, -0.54 to 0.13; P = 0.23), adiponectin (WMD, 1.17 μg/mL; 95% CI, -0.87 to 3.20; P = 0.26), and C-reactive protein (WMD, -1.10 mg/L; 95% CI, -2.39 to 0.20; P = 0.10). Subgroup analyses showed that fasting insulin levels were significantly more impacted in studies in which intervention participants experienced a weight reduction (WMD, -7.10 μU/mL; 95% CI, -10.31 to -3.90; P < 0.001).Conclusions: Exercise reduces fasting insulin levels in breast cancer survivors. This may be due to exercise-induced reductions in body weight.Impact: Practitioners and clinicians may better help breast cancer prognosis be improved through exercise, anticipating physiological effects on cancer. Cancer Epidemiol Biomarkers Prev; 26(3); 355-65. ©2016 AACR.

Muscle Strength, Body Composition, and Physical Activity in Women Receiving Chemotherapy for Breast Cancer

There is evidence to suggest that treatment of breast cancer with chemotherapy can induce metabolic changes in skeletal muscle. Women undergoing treatment for breast cancer with certain chemotherapeutic agents can experience declines in lean body mass and muscle strength and a subsequent increase in body weight. These alterations not only can lead to declines in physical function but also predispose women to weight-related chronic illness. Excess body weight may also play a role in the development or recurrence of breast cancer. There is evidence that physical exercise may improve body composition and enhance muscular endurance, flexibility, and quality of life (QOL) in women with breast cancer. While studies of aerobic, resistance, and combinations of aerobic and resistance exercise for women with breast cancer have been conducted, most studies employed supervised aerobic exercise sessions. Few studies have examined the role of resistance exercise or the combination of resistance and aerobic exercise in maintaining or increasing muscle strength while preserving lean body mass in this population. The relatively small sample sizes and short duration of physical activity interventions in previous studies make it difficult to detect dose responses to exercise training. Physical activity interventions with larger sample sizes and of longer duration are necessary to achieve long-term health outcomes. Physical activity interventions that include the older or more obese women with breast cancer are also needed, as this population may be most at risk of functional decline and the development of chronic illness. Interventions appropriate for women treated for breast cancer who have comorbid disease are also needed. Newer, more intense chemotherapy regimens may induce a differential effect on muscle strength and body composition. However, the role of physical activity during dose-dense chemotherapy protocols has not been established.

Heart failure in chemotherapy-related cardiomyopathy: Can exercise make a difference?

Medical therapies in oncology have resulted in better survival resulting in a large population who are at risk of early and late cardiac complications of chemotherapy. Cardiotoxicity related to chemotherapy can manifest decades after treatment with a threefold higher mortality rate as compared to idiopathic dilated cardiomyopathy. The leading cause of death in cancer survivors seems to be cardiac. Early detection and intervention could prevent progression of heart failure to end stage disease requiring advanced therapies such as implantation of ventricular assist devices or cardiac transplantation. This review focuses on the role of exercise in cardioprotection in this population. The current practice of depending on ejection fraction for diagnosis of heart failure is suboptimal to detect subclinical disease. It is also important to diagnose and treat early diastolic dysfunction as this tends to lead to heart failure with preserved ejection fraction. Hence we suggest an algorithm here that is based on using strain rate and tissue Doppler imaging modalities to detect subclinical systolic and diastolic dysfunction. Further research is warranted in terms of defining exercise prescriptions in this population. Human studies with multicenter participation in randomized controlled trials should be done to elucidate the intricacies of aerobic exercise intervention in cardiotoxicity dependent heart failure. It is also necessary to assess the utility of exercise interventions in the different chemotherapeutic regimens as they impact the outcomes.

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The need for exercise prescription to prevent cardiotoxicity in chemotherapy patients

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The molecular basis of exercise as an intervention

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Summary of existing evidence

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Need for further studies on the role of exercise in different chemotherapeutic regimens

The Effect of Exercise Training on Mediators of Inflammation in Breast Cancer Survivors: A Systematic Review with Meta-analysis

Several sources of evidence indicate that exercise during and after breast cancer could positively modulate the tumor microenvironment. This meta-analysis aimed to determine the effects of exercise training on mediators of inflammation in breast cancer survivors. We searched for randomized controlled trials published from January 1990 to March 2014. An inverse variance method of meta-analysis was performed using a random effects model in the presence of statistical heterogeneity. Eight high-quality trials (n = 478) were included. Exercise improved the serum concentrations of IL6 [weighted mean difference (WMD) = -0.55 pg/mL; 95% confidence interval (CI), -1.02 to -0.09], TNFα (WMD = -0.64 pg/mL; 95% CI, -1.21 to -0.06), IL8 (MD = -0.49 pg/mL; 95% CI, -0.89 to -0.09), and IL2 (WMD = 1.03 pg/mL; 95% CI, 0.40 to 1.67). No significant differences were found in the serum concentrations of C-reactive protein (WMD = -0.15; 95% CI, -0.56 to 0.25) or IL10 (WMD = 0.41; 95% CI, -0.18 to 1.02). Exercise training positively modulates chronic low-grade inflammation in women with breast cancer, which may impact upon carcinogenic mechanisms and the tumor microenvironment. These findings align with the other positive effects of exercise for breast cancer survivors, reinforcing the appropriateness of exercise prescription in this population. Cancer Epidemiol Biomarkers Prev; 25(7); 1009-17. ©2016 AACR.

Breast cancer treatment-associated cardiovascular toxicity and effects of exercise countermeasures

Advances in breast cancer treatment have improved disease-free survival and overall survival in women with early-stage breast cancer. However, these improvements may be attenuated by the adverse cardiovascular effects associated with breast cancer adjuvant therapy. Exercise may be a potential strategy to counteract these toxicities. The purpose of this paper is to provide an overview on the adverse cardiovascular effects of breast cancer therapy as well as the evidence supporting the potential cardioprotective effects of exercise training in breast cancer patients during and after treatment. We will also discuss research gaps and avenues for future research.