Oxidative Stress and Fitness Changes in Cancer Patients after Exercise Training

The interplay of exercise and polyphenols in cancer treatment: A focus on oxidative stress and antioxidant mechanisms

Exercise has been demonstrated to induce an elevated production of free radicals, leading to the onset of oxidative stress. Numerous studies highlight the positive impacts of aerobic exercise, primarily attributed to the increase in overall antioxidant capacity. The evidence suggests that engaging in aerobic exercise contributes to a reduction in the likelihood of advanced cancer and mortality. Oxidative stress occurs when there is an imbalance between the generation of free radicals and the collective antioxidant defense system, encompassing both enzymatic and nonenzymatic antioxidants. Typically, oxidative stress triggers the formation of reactive oxygen or nitrogen species, instigating or advancing various issues in cancers and other diseases. The pro-oxidant-antioxidant balance serves as a direct measure of this imbalance in oxidative stress. Polyphenols contain a variety of bioactive compounds, including flavonoids, flavanols, and phenolic acids, conferring antioxidant properties. Previous research highlights the potential of polyphenols as antioxidants, with documented effects on reducing cancer risk by influencing processes such as proliferation, angiogenesis, and metastasis. This is primarily attributed to their recognized antioxidant capabilities. Considering the extensive array of signaling pathways associated with exercise and polyphenols, this overview will specifically focus on oxidative stress, the antioxidant efficacy of polyphenols and exercise, and their intricate interplay in cancer treatment.

Influence of Amino Acids and Exercise on Muscle Protein Turnover, Particularly in Cancer Cachexia

Cancer cachexia is a multifaceted syndrome that impacts individuals with advanced cancer. It causes numerous pathological changes in cancer patients, such as inflammation and metabolic dysfunction, which further diminish their quality of life. Unfortunately, cancer cachexia also increases the risk of mortality in affected individuals, making it an important area of focus for cancer research and treatment. Several potential nutritional therapies are being tested in preclinical and clinical models for their efficacy in improving muscle metabolism in cancer patients. Despite promising results, no special nutritional therapies have yet been validated in clinical practice. Multiple studies provide evidence of the benefits of increasing muscle protein synthesis through an increased intake of amino acids or protein. There is also increasing evidence that exercise can reduce muscle atrophy by modulating protein synthesis. Therefore, the combination of protein intake and exercise may be more effective in improving cancer cachexia. This review provides an overview of the preclinical and clinical approaches for the use of amino acids with and without exercise therapy to improve muscle metabolism in cachexia.

Independent and joint associations of estimated cardiorespiratory fitness and its dynamic changes and obesity with the risk of hypertension: A prospective cohort

Our aim was to examine the independent and joint associations of estimated cardiorespiratory fitness (CRF) and its changes and obesity with risk of hypertension in a rural Chinese population. A prospective cohort including 9848 adults without hypertension at baseline was enrolled. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were estimated by logistic regression models. Restricted cubic splines were used to model the dose-response relationship. During 6 years follow-up, 2,019 individuals developed hypertension. A negative association between estimated CRF and hypertension incidence was observed, with the risk being 0.87 (0.84-0.90) per MET increment. For estimated CRF change, the risks of hypertension were 1.50 (1.27-1.77) and 0.75 (0.59-0.97) for decreasers and increasers, respectively, compared to maintainers. Joint analyses showed individuals in the overweight/obesity-fourth quartile of estimated CRF had a 2.08 times higher risk of hypertension than those in the normal weight-first quartile (Pinteraction < 0.05). Those overweight/obesity-decreasers had the highest risk (OR: 2.19, 95%CI: 1.71-2.81; Pinteraction < 0.05) compared to the normal-maintainers. Similar results for abdominal obesity were also observed. Estimated CRF and its dynamic changes showed a negative association with hypertension incidence in the rural Chinese population.

A bench to bedside perspective on anthracycline chemotherapy-mediated cardiovascular dysfunction: challenges and opportunities. A symposium review

Cardiovascular diseases (CVD) are the leading cause of death worldwide and the risk of developing CVD is markedly increased following anthracycline chemotherapy treatment. Anthracyclines are an essential component of the cancer treatment regimen used for common forms of cancer in male and female children, adolescents, young adults, and older adults. Increased CVD risk with anthracyclines occurs, in part, due to vascular dysfunction-impaired endothelial function and arterial stiffening. These features of vascular dysfunction also play a major role in other common disorders observed following anthracycline treatment, including chronic kidney disease, dementia, and exercise intolerance. However, the mechanisms by which anthracycline chemotherapy induces and sustains vascular dysfunction are incompletely understood. This budding area of biomedical research is termed cardio-oncology, which presents the unique opportunity for collaboration between physicians and basic scientists. This symposium, presented at Experimental Biology 2022, provided a timely update on this important biomedical research topic. The speakers presented observations made at levels from cells to mice to humans treated with anthracycline chemotherapeutic agents using an array of translational research approaches. The speaker panel included a diverse mix of female and male investigators and unique insight from a cardio-oncology physician-scientist. Particular emphasis was placed on challenges and opportunities in this field as well as mechanisms that could be viewed as therapeutic targets leading to novel treatment strategies.

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.

The association of cardiorespiratory fitness and the risk of hypertension: a systematic review and dose-response meta-analysis

Established evidence has indicated a negative correlation between cardiorespiratory fitness (CRF) and hypertension risk. In this study, we performed a meta-analysis to investigate the categorical and dose-response relationship between CRF and hypertension risk and the effects of CRF changes on hypertension risk reduction. The PubMed, Web of Science, and Embase databases were searched for relevant studies. The summarized relative risk (RR) and 95% confidence interval (95% CI) were estimated using the DerSimonian and Laird random effect model, and the dose-response relationship between CRF and hypertension risk was characterized using generalized least-squares regression and restricted cubic splines. Nine cohorts describing 110,638 incident hypertension events among 1,618,067 participants were included in this study. Compared with the lowest category of CRF, the RR of hypertension was 0.63 (95% CI: 0.56-0.70) for the highest CRF category and 0.85 (95% CI: 0.80-0.91) for the moderate category of CRF. For a 1-metabolic equivalent increment in CRF, the pooled RR of hypertension was 0.92 (95% CI: 0.90-0.94) in the total population. The RR of hypertension was 0.71 (95% CI: 0.64-0.79) for participants with CRF increased compared with those whose CRF was decreased over time. In conclusion, our meta-analysis supports the widely held notion of a negative dose-dependent relationship between CRF and hypertension risk.

Nutritional and Exercise Interventions in Cancer-Related Cachexia: An Extensive Narrative Review

One of the common traits found in cancer patients is malnutrition and cachexia, which affects between 25% to 60% of the patients, depending on the type of cancer, diagnosis, and treatment. Given the lack of current effective pharmacological solutions for low muscle mass and sarcopenia, holistic interventions are essential to patient care, as well as exercise and nutrition. Thus, the present narrative review aimed to analyze the nutritional, pharmacological, ergonutritional, and physical exercise strategies in cancer-related cachexia. The integration of multidisciplinary interventions could help to improve the final intervention in patients, improving their prognosis, quality of life, and life expectancy. To reach these aims, an extensive narrative review was conducted. The databases used were MedLine (PubMed), Cochrane (Wiley), Embase, PsychINFO, and CinAhl. Cancer-related cachexia is a complex multifactorial phenomenon in which systemic inflammation plays a key role in the development and maintenance of the symptomatology. Pharmacological interventions seem to produce a positive effect on inflammatory state and cachexia. Nutritional interventions are focused on a high-energy diet with high-density foods and the supplementation with antioxidants, while physical activity is focused on strength-based training. The implementation of multidisciplinary non-pharmacological interventions in cancer-related cachexia could be an important tool to improve traditional treatments and improve patients' quality of life.

Modulating Tumour Hypoxia in Prostate Cancer Through Exercise: The Impact of Redox Signalling on Radiosensitivity

Prostate cancer is a complex disease affecting millions of men globally. Radiotherapy (RT) is a common treatment modality although treatment efficacy is dependent upon several features within the tumour microenvironment (TME), especially hypoxia. A hypoxic TME heightens radioresistance and thus disease recurrence and treatment failure continues to pose important challenges. However, the TME evolves under the influence of factors in systemic circulation and cellular crosstalk, underscoring its potential to be acutely and therapeutically modified. Early preclinical evidence suggests exercise may affect tumour growth and some of the benefits drawn, could act to radiosensitise tumours to treatment. Intracellular perturbations in skeletal muscle reactive oxygen species (ROS) stimulate the production of numerous factors that can exert autocrine, paracrine, and endocrine effects on the prostate. However, findings supporting this notion are limited and the associated mechanisms are poorly understood. In light of this preclinical evidence, we propose systemic changes in redox signalling with exercise activate redox-sensitive factors within the TME and improve tumour hypoxia and treatment outcomes, when combined with RT. To this end, we suggest a connection between exercise, ROS and tumour growth kinetics, highlighting the potential of exercise to sensitise tumour cells to RT, and improve treatment efficacy.

Exercise and Oxidative Stress Biomarkers among Adult with Cancer: A Systematic Review

Evidence shows that exercise can have a favourable effect in cancer patients. The exercise’s clinical benefits are likely to concern multiple interrelated biological pathways, among which oxidative stress plays a key role. Regular training can induce an adaptive response that strengthens the antioxidative status of the body. To formulate public health recommendations regarding the optimal exercise prescription for cancer patients, a detailed understanding is needed regarding the effect of exercise on variables linked to oxidative stress and antioxidant status of patients. The goal of this systematic review, based on PRISMA, was to explore and critically analyse the evidence regarding the efficacy of exercise on oxidative stress biomarkers among people with cancer. Study search was conducted in the following databases: PubMed, Cochrane, CINAHL, Embase, PEDro, and SPORTDiscus. The studies’ quality was assessed with the Cochrane risk-of-bias tool and STROBE scale. After identification and screening steps, 10 articles were included. The findings provide an encouraging picture of exercise, including resistance training and aerobic activities, in people with cancer. The exercise improved the indicators of the total antioxidant capacity, increased the antioxidant enzymes’ activity, or reduced the biomarkers of oxidative damage in various forms of cancer such as breast, lung, head, and neck. Regarding oxidative DNA damage, the role of exercise intervention has been difficult to assess. The heterogeneity of study design and the plethora of biomarkers measured hampered the comparison of the articles. This limited the possibility of establishing a comprehensive conclusion on the sensitivity of biomarkers to estimate the exercise’s benefits. Further high-quality studies are required to provide data regarding oxidative stress biomarkers responding to exercise. This information will be useful to assess the efficacy of exercise in people with cancer and support the appropriate prescription of exercise in anticancer strategy.

Exercise Cardio-Oncology: Exercise as a Potential Therapeutic Modality in the Management of Anthracycline-Induced Cardiotoxicity

Anthracyclines are one of the most effective chemotherapy agents and have revolutionized cancer therapy. However, anthracyclines can induce cardiac injuries through ‘multiple-hits', a series of cardiovascular insults coupled with lifestyle risk factors, which increase the risk of developing short- and long-term cardiac dysfunction and cardiovascular disease that potentially lead to premature mortality following cancer remission. Therefore, the management of anthracycline-induced cardiotoxicity is a serious unmet clinical need. Exercise therapy, as a non-pharmacological intervention, stimulates numerous biochemical and physiologic adaptations, including cardioprotective effects, through the cardiovascular system and cardiac muscles, where exercise has been proposed to be an effective clinical approach that can protect or reverse the cardiotoxicity from anthracyclines. Many preclinical and clinical trials demonstrate the potential impacts of exercise on cardiotoxicity; however, the underlying mechanisms as well as how to implement exercise in clinical settings to improve or protect against long-term cardiovascular disease outcomes are not clearly defined. In this review, we summarize the current evidence in the field of “exercise cardio-oncology” and emphasize the utilization of exercise to prevent and manage anthracycline-induced cardiotoxicities across high-risk and vulnerable populations diagnosed with cancer.

Exercise training improves postural steadiness in cancer survivors undergoing chemotherapy

BACKGROUND

Cancer and cancer treatments negatively affect somatosensory, vestibular, and visual inputs that regulate postural stability and balance, increasing the risk of falling. Exercise training has been shown to mitigate other negative side effects of cancer treatments, such as reducing peripheral neuropathy.

RESEARCH QUESTION

How does 12 weeks of supervised exercise training influence postural stability in cancer survivors who receive chemotherapy?

METHODS

Postural stability of cancer survivors (n = 25; mass = 79.0 ± 22.6 kg; height = 1.66 ± 0.08 m; age = 61 ± 10 years) receiving chemotherapy was assessed prior to and following a 12-week individualized exercise training program by quantifying changes in center of pressure data. A series of 2-factor (pre/post x condition) analysis of variance with repeated measures were used to identify differences between conditions and pre- and post- training program on time and frequency domain measures.

RESULTS

Mediolateral root mean square excursion (p = 0.040; es = 0.20) and resultant mean frequency (p = 0.044; es = 0.29) of the center of pressure trajectory were found to be significantly different between pre- and post-training program. Further, participants dealt better with perturbations after completing the training program by reducing mediolateral root mean square excursion and 95 % confidence ellipse when visual stimulus was removed.

SIGNIFICANCE

Supervised exercise training in cancer patients undergoing chemotherapy improves postural stability in the mediolateral direction. Given that mediolateral movement of the center of pressure has previously been associated with fallers in other populations, exercise training during cancer treatments may be beneficial.

Nutraceuticals and Exercise against Muscle Wasting during Cancer Cachexia

Cancer cachexia (CC) is a debilitating multifactorial syndrome, involving progressive deterioration and functional impairment of skeletal muscles. It affects about 80% of patients with advanced cancer and causes premature death. No causal therapy is available against CC. In the last few decades, our understanding of the mechanisms contributing to muscle wasting during cancer has markedly increased. Both inflammation and oxidative stress (OS) alter anabolic and catabolic signaling pathways mostly culminating with muscle depletion. Several preclinical studies have emphasized the beneficial roles of several classes of nutraceuticals and modes of physical exercise, but their efficacy in CC patients remains scant. The route of nutraceutical administration is critical to increase its bioavailability and achieve the desired anti-cachexia effects. Accumulating evidence suggests that a single therapy may not be enough, and a bimodal intervention (nutraceuticals plus exercise) may be a more effective treatment for CC. This review focuses on the current state of the field on the role of inflammation and OS in the pathogenesis of muscle atrophy during CC, and how nutraceuticals and physical activity may act synergistically to limit muscle wasting and dysfunction.

Effect of Exercise Training on Exercise Tolerance and Level of Oxidative Stress for Head and Neck Cancer Patients Following Chemotherapy

Background

Chemotherapy decreases fitness performance via repression of cardiopulmonary function and oxidative stress. This study was designed to investigate whether exercise intervention could improve exercises capacity and reduce systemic oxidative stress in patients with head and neck (H&N) cancer receiving chemotherapy.

Methods

This is a single-center study. Forty-two H&N cancer patients who were undergoing chemotherapy were recruited in this study. An 8-week exercise intervention was performed by conducting the combination of aerobic and resistance exercise 3 days a week. The exercise training was conducted by a physiotherapist. The exercise capacity and exercise responses were measured from blood pressure (BP) and heart rate (HR). Oxidative stress markers from human plasma, such as total antioxidant capacity, 8-hydroxy-2'-deoxyguanosine, malondialdehyde, and carbonyl content, were tested by activity kits.

Results

We provide compelling evidence that exercise training ameliorated exercise responses and increased exercise capacity by repressing resting BP and increasing 1- and 3-min BP recovery. We also found the resting HR was reduced, and the 1- and 3-min HR recovery was increased after exercise training. In addition, the rating of perceived exertion after the peak exercise was reduced after exercise intervention. We also found that exercise training repressed oxidative stress markers by elevation of total antioxidant capacity and suppression of 8-OHd and carbonyl content in plasma.

Discussion

We clearly demonstrate that exercise can promote exercise capacity and reduce oxidative stress in H&N cancer patients receiving chemotherapy, which might guide new therapeutic approaches for cancer patients, especially those undergoing chemotherapy.

Chronic fatigue in myelodysplastic syndromes: Looking beyond anemia

Chronic fatigue is the most common and severe symptom in myelodysplastic syndromes (MDS) and has a strong negative association with health-related quality of life (HRQoL). Despite anemia being the most common objective manifestation of MDS, and the associated link between anemia and fatigue, evidence on treatments which temporarily mitigate anemia is equivocal regarding the effects on fatigue. Furthermore, previous work has found weak associations between anemia and chronic fatigue in MDS. As such, given that improving HRQoL is one of the primary treatment aims in MDS, further work is required to identify other potential contributors to chronic fatigue in these patients. In addition to anemia, MDS is associated with numerous other deviations in physiological homeostasis and has negative psychological consequences with links to chronic fatigue. Accordingly, the present review provides several potential aetiologic agents relevant to chronic fatigue in MDS which can be used to guide future research in this field.

Effect of C242T Polymorphism in the Gene Encoding the NAD(P)H Oxidase p22phox Subunit and Aerobic Fitness Levels on Redox State Biomarkers and DNA Damage Responses to Exhaustive Exercise: A Randomized Trial

NAD(P)H oxidases (NOXs) constitute a principal source of cellular reactive oxygen species (ROS) and contribute to exercise-induced ROS production in the skeletal muscle. Here, we aimed to investigate the effect of single-bout exhaustive exercise on redox state biomarkers and oxidative DNA damage based on the C242T polymorphism in the gene encoding NOXs subunit p22^phox (CYBA) and aerobic fitness levels. We enrolled 220 healthy adults in their 20s (men, n = 110; women, n = 110), who were divided into CC genotype and T allele groups through the analysis of the CYBA C242T polymorphism. Furthermore, maximum oxygen uptake (VO₂max) was evaluated to divide subjects into high fitness (HF; 70th percentile for aerobic fitness) and mid-range fitness (MF; 40-60th percentile for aerobic fitness) groups, with a total of 32 subjects assigned to four groups (eight subjects per group): CC genotype and HF group (CC + HF), CC genotype and MF group (CC + MF), T allele and HF group (T + HF), and T allele and MF group (T + MF). All subjects performed treadmill running exercise at 85% of VO₂max until exhaustion. Plasma lactate, malondialdehyde (MDA), superoxide dismutase (SOD), and lymphocyte DNA damage (tail DNA percentage [TD], tail length [TL], and the tail moment [TM]) were measured in the blood samples obtained immediately before (IBE), immediately after (IAE), and 30 min after exercise (30 MAE). Plasma lactate levels, SOD activities, and lymphocyte DNA damage markers (TD, TL, and TM) were significantly increased at IAE than that at IBE and significantly decreased at 30 MAE (p < 0.05). All groups displayed increased plasma MDA levels at IAE rather than at IBE, with CC + MF being significantly higher than T + HF (p < 0.05); only the CC + HF and T + HF groups exhibited a significant reduction at 30 MAE (p < 0.05). Moreover, TL at IAE was significantly higher in the CC + MF group than in the T + HF group (p < 0.05), and significantly higher in the CC + MF and CC + HF groups than in the T + HF group at 30 MAE (p < 0.05). TM was significantly higher in the T + MF than in the T + HF group at IAE (p < 0.05) and that of CC + MF was significantly higher than CC + HF and T + HF values at IAE and 30 MAE (p < 0.05). These results suggest that single-bout exhaustive exercise could induce peripheral fatigue and the accumulation of temporary redox imbalance and oxidative DNA damage. Moreover, high aerobic fitness levels combined with the T allele may protect against exercise-induced redox imbalance and DNA damage.

Oncology and Cardiac Rehabilitation: An Underrated Relationship

Cancer and cardiovascular diseases are globally the leading causes of mortality and morbidity. These conditions are closely related, beyond that of sharing many risk factors. The term bidirectional relationship indicates that cardiovascular diseases increase the likelihood of getting cancer and vice versa. The biological and biochemical pathways underlying this close relationship will be analyzed. In this new overlapping scenario, physical activity and exercise are proven protective behaviors against both cardiovascular diseases and cancer. Many observational studies link an increase in physical activity to a reduction in either the development or progression of cancer, as well as to a reduction in risk in cardiovascular diseases, a non-negligible cause of death for long-term cancer survivors. Exercise is an effective tool for improving cardio-respiratory fitness, quality of life, psychological wellbeing, reducing fatigue, anxiety and depression. Finally, it can counteract the toxic effects of cancer therapy. The protection obtained from physical activity and exercise will be discussed in the various stages of the cancer continuum, from diagnosis, to adjuvant therapy, and from the metastatic phase to long-term effects. Particular attention will be paid to the shelter against chemotherapy, radiotherapy, cardiovascular risk factors or new onset cardiovascular diseases. Cardio-Oncology Rehabilitation is an exercise-based multi-component intervention, starting from the model of Cardiac Rehabilitation, with few modifications, to improve care and the prognosis of a patient's cancer. The network of professionals dedicated to Cardiac Rehabilitation is a ready-to-use resource, for implementing Cardio-Oncology Rehabilitation.

Effect of strength training and antioxidant supplementation on perceived and performance fatigability in breast cancer survivors: a randomized, double-blinded, placebo-controlled study

This randomized, double-blinded, placebo-controlled study aimed to investigate the effect of strength training (ST) combined with vitamin C and E supplementation on perceived and performance fatigability in breast cancer survivors (BCS). Twenty-five BCS were randomly assigned to 1 of 2 groups: vitamins (VIT; n = 12; 51.0 ± 9.0 years) or placebo (PLA; n = 13; 48.2 ± 8.3 years). Both groups performed a 10-week ST protocol, twice a week. The VIT group was supplemented with vitamins C (500 mg/day) and E (180 mg/day) and the PLA group with polydextrose (1 g/day), once a day after breakfast. At the beginning and at the end of the training period, perceived fatigability was assessed using Multidimensional Fatigue Inventory (MFI)-20 (general fatigue and physical fatigue). Performance fatigability was assessed during 30 maximal isokinetic knee extensions at 120°/s. General fatigue decreased similarly in the VIT (p = 0.004) and PLA (p = 0.011) groups. Physical fatigue decreased similarly in the VIT (p = 0.011) and PLA (p = 0.001) groups. Performance fatigability also decreased similarly in the VIT (p = 0.026) and PLA (p < 0.001) groups. There was no difference between groups at any moment (p > 0.05). In summary, antioxidant supplementation does not add any positive synergistic effect to ST in terms of improving perceived or performance fatigability in BCS. This clinical trial is registered in the Brazilian Clinical Trials Registry, number RBR-843pth (UTN no.: U1111-1222-6511). Novelty ST with maximal repetitions reduces perceived and performance fatigability of BCS. Vitamins C and E supplementation does not add any positive synergistic effect to ST in terms of reducing fatigability in BCS.

Exercise shapes redox signaling in cancer

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

Cost Savings Analysis of Individualized Exercise Oncology Programs

Background: The physical and economic toll of cancer make it a high health priority. The rising cost of cancer care is now a primary focus for patients, payers, and providers. Escalating costs of clinical trials and national drug regulations have led the median monthly costs of cancer drugs to rise from less than $100 in 1965 to 1969, to more than $5000 in 2005 to 2009, stressing the importance of finding innovative ways to reduce cost burden. In the present study, we report the economic evaluation of an individualized exercise oncology program beginning early after diagnosis. Methods: An independent research group, ASCEND Innovations, retrospectively analyzed patient records to statistically demonstrate the impact of exercise oncology during cancer treatment. All patients completed 12 weeks of prescribed, individualized exercise that included cardiovascular, strength training, and flexibility components. The 3 primary hospital measures leveraged for statistical comparison before and after supportive care enrollment were number of encounters, number of readmissions, and average total charges, as well as emergency room visits and length of hospital stay (P < .05). Results: The resulting dataset consisted of 1493 total hospital encounters for 147 unique patients. The results statistically demonstrate a positive effect of exercise oncology during cancer care, in terms of reductions in overall cost per patient pre- to post-intervention. Conclusions: Individualized exercise oncology programs should be employed as part of the national standard of care for individuals battling cancer, in order to improve patient outcome and reduce cost burden.

Effects of Aerobic Exercise on Oxidative Stress in Patients Diagnosed with Cancer: A Narrative Review

Background: Oxidative stress (OS) can bring about an imbalance between the production of free radicals (pro-oxidants) and their elimination by protective mechanisms (antioxidants). Exercise and/or physical activity (PA) may provide a mechanism to control the variation and equilibrium between pro-oxidants and antioxidants.

Purpose: The purpose of this narrative review is to investigate the evidence regarding the effect of exercise and/or PA on OS among individuals diagnosed with cancer. 

Methods: A narrative review study design involved a literature search (August 2016) across the databases: Cumulative Index of Nursing and Allied Health Literature (CINAHL), Cochrane, Excerpta Medica database (Embase), and PubMed. Articles included those published from January 2000 - August 2016; inclusive of the search terms “cancer” AND “neoplasm” AND “oncology” AND “oxidative stress” AND “exercise” AND “physical activity”; written in the English language; and utilizing human subjects. The references of the selected articles were then reviewed to identify any qualifying articles. A modified Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) review of each article was completed by two investigators.

Results: Eight articles met the final inclusion criteria. Moderate exercise may provide protective mechanisms against OS via increased antioxidant activity, while exhaustive exercise may be responsible for increased levels of OS, increasing the risk for malignancy. While increased OS levels are utilized by current oncologic therapies to damage malignant and premalignant cells, they also damage healthy cells (cardiac, nerve, and lymphatic).

Conclusion: Moderate levels of exercise and/or PA may provide preventative and protective qualities against the negative side effects associated with increased OS from cancer treatment.

Exercise as Adjunct Therapy in Cancer

Data from observational studies indicate that both physical activity as well as exercise (ie, structured physical activity) is associated with reductions in the risk of recurrence and cancer mortality after a diagnosis of certain forms of cancer. Emerging evidence from preclinical studies indicates that physical activity/exercise paradigms regulate intratumoral vascular maturity and perfusion, hypoxia, and metabolism and augments the antitumor immune response. Such responses may, in turn, enhance response to standard anticancer treatments. For instance, exercise improves efficacy of chemotherapeutic agents, and there is rationale to believe that it will also improve radiotherapy response. This review overviews the current preclinical as well as clinical evidence supporting exercise modulation of therapeutic response and postulated biological mechanisms underpinning such effects. We also examine the implications for tumor response to radiation, chemotherapy, and immunotherapy.

Energy balance and gastrointestinal cancer: risk, interventions, outcomes and mechanisms

Obesity increases the risk of multiple gastrointestinal cancers and worsens disease outcomes. Conversely, strong inverse associations have emerged between physical activity and colon cancer and possibly other gastrointestinal malignancies. The effect of weight loss interventions - such as modifications of diet and/or physical activity or bariatric surgery - remains unclear in patients who are obese and have gastrointestinal cancer, although large clinical trials are underway. Human intervention studies have already shed light on potential mechanisms underlying the energy balance-cancer relationship, with preclinical models supporting emerging pathway effects. Central to interventions that reduce obesity or increase physical activity are pluripotent cancer-preventive effects (including reduced systemic and adipose tissue inflammation and angiogenesis, altered adipokine levels and improved insulin resistance) that directly interface with the hallmarks of cancer. Other mechanisms, such as DNA repair, oxidative stress and telomere length, immune function, effects on cancer stem cells and the microbiome, could also contribute to energy balance effects on gastrointestinal cancers. Although some mechanisms are well understood (for instance, systemic effects on inflammation and insulin signalling), other areas remain unclear. The current state of knowledge supports the need to better integrate mechanistic approaches with preclinical and human studies to develop effective, personalized diet and exercise interventions to reduce the burden of obesity on gastrointestinal cancer.

Effects of an Exercise Intervention on Cancer-Related Fatigue and Its Relationship to Markers of Oxidative Stress

Background: Although the underlying mechanisms of cancer-related fatigue (CRF) are not fully characterized, treatment-associated oxidative stress may play a role. The purpose of this study was to determine the effect of an exercise intervention on the relationship between CRF and oxidative stress. Methods: Upon cessation of radiation or chemotherapy, 8 cancer patients participated in a 10-week exercise intervention (EX), while 7 continued standard care (CON). Blood draws and fatigue questionnaires were administered to cancer patients before and after the intervention as well as to 7 age-matched individuals with no cancer history. Changes in plasma 8-hydroxy-deoxyguanosine (8-OHdG), protein carbonyls, antioxidant capacity, and fatigue were compared between groups. Correlations between CRF and oxidative stress were evaluated. Results: Mean total fatigue scores decreased significantly (5.0 ± 2.2 to 2.6 ± 1.5, P < .05) in EX, but not in CON. Antioxidant capacity significantly increased (+41%; P < .05) and protein carbonyls significantly decreased (−36%; P < .05) in EX, but not in CON. Increases in antioxidant capacity were significantly correlated with reductions in affective (r = −.49), sensory (r = −.47), and cognitive fatigue (r = −.58). Changes in total (r = .46) and affective (r = .47) fatigue exhibited significant correlations with changes in 8-OHdG over time, while behavioral (r = .46) and sensory (r = .47) fatigue changes were significantly correlated with protein carbonyls. Conclusions: Oxidative stress may be implicated in CRF, while improved antioxidant capacity following an exercise intervention may play a role in mitigating CRF in cancer survivors.

Evaluation of the effects of a clinically implemented exercise program on physical fitness, fatigue, and depression in cancer survivors

PURPOSE

Despite national recommendations, exercise programs are still not clinically implemented as standard of care for cancer survivors. This investigation examined the effects of a clinically implemented and personalized exercise program on physical fitness, fatigue, and depression in a diverse population of cancer survivors. The association of various participant characteristics on program performance was also examined.

METHODS

Data were collected from 170 cancer survivors who had participated in a clinical exercise program. Any cancer type was included and survivors were either undergoing medical treatment or had completed treatment (< 6 months prior to program initiation). Baseline and post program measures of estimated VO₂peak, grip strength, fatigue, and depression were compared in survivors who completed the program follow-up. Multiple regressions were performed to investigate the association of age, gender, body mass index (BMI), and medical treatment status on baseline and change scores in outcome measures, as well as program adherence.

RESULTS

All measures improved in participants who completed the program (p < 0.01). Age, gender, and BMI were associated with baseline measures of estimated VO₂peak and grip strength (p < 0.01), and age was inversely associated with baseline fatigue (p = 0.02). Only BMI was inversely associated with change in estimated VO₂peak (p < 0.01). No participant characteristics or baseline measures were predictive of program adherence (p > 0.05).

CONCLUSION

This investigation provides evidence that a personalized, clinical exercise program can be effective at improving physical fitness, fatigue, and depression in a diverse population of cancer survivors.

Combined aerobic and resistance exercise training for improving reproductive function in infertile men: a randomized controlled trial

This randomized controlled trial was conducted to examine the effects of 24 weeks of combined aerobic and resistance exercise training on seminal markers of inflammation and oxidative stress as well as markers of male reproductive function and reproductive performance in infertile patients. Of a total of 1296 infertile patients (aged 25–40 years) who were screened, 556 were randomly assigned to exercise (n = 278) and nonexercise (n = 278) groups. Semen samples were taken before and at 12 and 24 weeks as well as 7 and 30 days post-intervention. The training program reduced seminal proinflammatory cytokines (interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor alpha) and markers of oxidative stress (reactive oxygen species, malondialdehyde, and 8-isoprostane) (P < 0.05). Additional improvements were also achieved in seminal antioxidant defense system (superoxide dismutase, catalase, and total antioxidant capacity) (P < 0.05). Training-induced changes in inflammation and oxidative stress status correlated with favorable improvements in semen parameters, sperm DNA integrity, and pregnancy rate (P < 0.05). In conclusion, these results support the evidence for the favorable effects of combined aerobic and resistance exercise training in male factor infertility.