Distance-based delivery of exercise for people treated for breast, prostate or colorectal cancer: a study protocol for a randomised controlled trial of EX-MED Cancer Sweden

BACKGROUND

Regular exercise has been shown to have beneficial health effects in cancer survivors, including improving quality of life and other important health outcomes. However, providing people with cancer with easily accessible, high-quality exercise support and programs is a challenge. Therefore, there is a need to develop easily accessible exercise programs that draw upon the current evidence. Supervised, distance-based exercise programs have the benefit of reaching out to many people whilst providing the support of an exercise professional. The aim of the EX-MED Cancer Sweden trial is to examine the effectiveness of a supervised, distance-based exercise program, in people previously treated for breast, prostate, or colorectal cancer, on health-related quality of life (HRQoL), as well as other physiological and patient-reported health outcomes.

METHODS

The EX-MED Cancer Sweden trial is a prospective randomised controlled trial including 200 people that have completed curative treatment for breast, prostate, or colorectal cancer. Participants are randomly allocated to an exercise group or a routine care control group. The exercise group will participate in a supervised, distanced-based exercise program delivered by a personal trainer who has undertaken specialised exercise oncology education modules. The intervention consists of a combination of resistance and aerobic exercises with participants completing two 60-min sessions per week for 12 weeks. The primary outcome is HRQoL (EORTC QLQ-C30) assessed at baseline, 3- (end of intervention and primary endpoint) and 6-months post-baseline. Secondary outcomes are physiological (cardiorespiratory fitness, muscle strength, physical function, body composition) and patient-reported outcomes (cancer-related symptoms, fatigue, self-reported physical activity), and self-efficacy of exercise. Furthermore, the trial will explore and describe the experiences of participation in the exercise intervention.

DISCUSSION

The EX-MED Cancer Sweden trial will provide evidence regarding the effectiveness of a supervised, distance-based exercise program for survivors of breast, prostate, and colorectal cancer. If successful, it will contribute to the implementation of flexible and effective exercise programs as part of the standard of care for people following cancer treatment, which is likely to contribute to a reduction in the burden of cancer on the individual, health care system and society.

TRIAL REGISTRATION

www.

CLINICALTRIALS

gov NCT05064670. Registered on October 1, 2021.

Exercise reduces intramuscular stress and counteracts muscle weakness in mice with breast cancer

BACKGROUND

Patients with breast cancer exhibit muscle weakness, which is associated with increased mortality risk and reduced quality of life. Muscle weakness is experienced even in the absence of loss of muscle mass in breast cancer patients, indicating intrinsic muscle dysfunction. Physical activity is correlated with reduced cancer mortality and disease recurrence. However, the molecular processes underlying breast cancer-induced muscle weakness and the beneficial effect of exercise are largely unknown.

METHODS

Eight-week-old breast cancer (MMTV-PyMT, PyMT) and control (WT) mice had access to active or inactive in-cage voluntary running wheels for 4 weeks. Mice were also subjected to a treadmill test. Muscle force was measured ex vivo. Tumour markers were determined with immunohistochemistry. Mitochondrial biogenesis and function were assessed with transcriptional analyses of PGC-1α, the electron transport chain (ETC) and antioxidants superoxide dismutase (Sod) and catalase (Cat), combined with activity measurements of SOD, citrate synthase (CS) and β-hydroxyacyl-CoA-dehydrogenase (βHAD). Serum and intramuscular stress levels were evaluated by enzymatic assays, immunoblotting, and transcriptional analyses of, for example, tumour necrosis factor-α (TNF-α) and p38 mitogen-activated protein kinase (MAPK) signalling.

RESULTS

PyMT mice endured shorter time and distance during the treadmill test (~30%, P < 0.05) and ex vivo force measurements revealed ~25% weaker slow-twitch soleus muscle (P < 0.001). This was independent of cancer-induced alteration of muscle size or fibre type. Inflammatory stressors in serum and muscle, including TNF-α and p38 MAPK, were higher in PyMT than in WT mice (P < 0.05). Cancer-induced decreases in ETC (P < 0.05, P < 0.01) and antioxidant gene expression were observed (P < 0.05). The exercise intervention counteracted the cancer-induced muscle weakness and was accompanied by a less aggressive, differentiated tumour phenotype, determined by increased CK8 and reduced CK14 expression (P < 0.05). In PyMT mice, the exercise intervention led to higher CS activity (P = 0.23), enhanced β-HAD and SOD activities (P < 0.05), and reduced levels of intramuscular stressors together with a normalization of the expression signature of TNFα-targets and ETC genes (P < 0.05, P < 0.01). At the same time, the exercise-induced PGC-1α expression, and CS and β-HAD activity was blunted in muscle from the PyMT mice as compared with WT mice, indicative that breast cancer interfere with transcriptional programming of mitochondria and that the molecular adaptation to exercise differs between healthy mice and those afflicted by disease.

CONCLUSIONS

Four-week voluntary wheel running counteracted muscle weakness in PyMT mice which was accompanied by reduced intrinsic stress and improved mitochondrial and antioxidant profiles and activities that aligned with muscles of healthy mice.

Long-Term Favorable Effects of Physical Exercise on Burdensome Symptoms in the OptiTrain Breast Cancer Randomized Controlled Trial

Purpose: We evaluate longitudinal changes in symptom clusters and core burdensome symptoms in breast cancer patients who participated in the OptiTrain trial. Methods: 240 women were randomized to 16 weeks of supervised exercise (RT-HIIT or AT-HIIT) or usual care (UC) during adjuvant chemotherapy. Symptom clusters were composed using the Memorial Symptom Assessment Scale (MSAS), assessed at baseline, 16 weeks and 12 months later. Three symptom clusters were formed. Results: Three symptom clusters were identified: "emotional," "treatment-related toxicity," and "physical," with core burdensome symptoms present over time. At 16 weeks, the reported burdens of "feeling sad" (RT-HIIT vs UC: effect size [ES] = -0.69; AT-HIIT vs UC: ES = -0.56) and "feeling irritable" (ES = -0.41 RT-HIIT; ES = -0.31 AT-HIIT) were significantly lower in both intervention groups compared with UC. At 12 months, the AT-HIIT group continued to have significantly lower scores for the core burdensome symptoms "feeling sad" (ES = -0.44), "feeling irritable" (ES = -0.44), and "changes in the way food tastes" (ES = -0.53) compared with UC. No between-group differences were found for physical symptoms. Conclusion: We identified 3 symptom clusters in breast cancer patients during and after adjuvant chemotherapy, composed of "emotional," "treatment-related toxicity," and "physical" symptoms. After treatment completion up to 12 months post-baseline, patients in the physical exercise groups reported lower symptom burden scores for emotional symptoms, compared with UC. Our findings indicate a preserved and long-term beneficial effect of physical exercise on self-reported emotional well-being in chemotherapy-treated breast cancer patients.

High intensity exercise during breast cancer chemotherapy - effects on long-term myocardial damage and physical capacity - data from the OptiTrain RCT

BACKGROUND

Adjuvant systemic breast cancer treatment improves disease specific outcomes, but also presents with cardiac toxicity. In this post-hoc exploratory analysis of the OptiTrain trial, the effects of exercise on cardiotoxicity were monitored by assessing fitness and biomarkers over the intervention and into survivorship. Methods; Women starting chemotherapy were randomized to 16-weeks of resistance and high-intensity interval training (RT-HIIT), moderate-intensity aerobic and high-intensity interval training (AT-HIIT), or usual care (UC). Outcome measures included plasma troponin-T (cTnT), Nt-pro-BNP and peak oxygen uptake (VO_2peak), assessed at baseline, post-intervention, and at 1- and 2-years.

RESULTS

For this per-protocol analysis, 88 women met criteria for inclusion. Plasma cTnT increased in all groups post-intervention. At the 1-year follow-up, Nt-pro-BNP was lower in the exercise groups compared to UC. At 2-years there was a drop in VO_2peak for patients with high cTnT and Nt-pro-BNP. Fewer patients in the RT-HIIT group fulfilled biomarker risk criteria compared to UC (OR 0.200; 95% CI = 0.055-0.734).

CONCLUSIONS

In this cohort, high-intensity exercise was associated with lower levels of NT-proBNP 1-year post-baseline, but not with cTnT directly after treatment completion. This may, together with the preserved VO_2peak in patients with low levels of biomarkers, indicate a long-term cardioprotective effect of exercise.

TRIAL REGISTRATION

Clinicaltrials. govNCT02522260 , Registered 13th of august 2015 - Retrospectively Registered.

Sense of coherence and its relationship to participation, cancer-related fatigue, symptom burden, and quality of life in women with breast cancer participating in the OptiTrain exercise trial

PURPOSE

This study examined the Sense of Coherence (SOC) of patients participating in the randomized controlled 'Optimal Training for Women with Breast Cancer' (OptiTrain) study and assessed how patient characteristics were associated with SOC. Secondary aims were to assess the association between SOC and patients' participation in this study and to determine whether SOC moderates the effect of the 16-week exercise intervention on fatigue, quality of life (QoL), and symptom burden in women with breast cancer undergoing chemotherapy.

METHODS

Modified Poisson regression analyses were conducted to determine the relative risk of weak-normal SOC versus strong SOC in terms of exercise session attendance, study and intervention dropout, and long absence rates. Analyses of covariance were performed to assess whether SOC moderated the effect of the exercise intervention (pinteraction ≤ 0.10).

RESULTS

Two hundred and forty women with early breast cancer (mean age 53 ± 10) participated in the OptiTrain study. Women with strong SOC reported less fatigue, lower symptom burden, and higher QoL. Women with weak-normal SOC were significantly more likely to drop out from the OptiTrain study and tended to have slightly poorer exercise session attendance. Women with breast cancer and weaker SOC benefitted as much from the exercise intervention, in terms of fatigue and QoL, as those with stronger SOC (pinteraction > 0.10).

CONCLUSIONS

Strong SOC appears to be associated with a more positive subjective state of health. Women with weak-normal SOC may need additional support to encourage participation and adherence in exercise trials. Assessing SOC may assist clinicians to identify and provide extra support for participants with weak SOC, who may be less inclined to participate in exercise programs.

Cytotoxic T-cells mediate exercise-induced reductions in tumor growth

Exercise has a wide range of systemic effects. In animal models, repeated exertion reduces malignant tumor progression, and clinically, exercise can improve outcome for cancer patients. The etiology of the effects of exercise on tumor progression are unclear, as are the cellular actors involved. We show here that in mice, exercise-induced reduction in tumor growth is dependent on CD8+ T cells, and that metabolites produced in skeletal muscle and excreted into plasma at high levels during exertion in both mice and humans enhance the effector profile of CD8+ T-cells. We found that activated murine CD8+ T cells alter their central carbon metabolism in response to exertion in vivo, and that immune cells from trained mice are more potent antitumor effector cells when transferred into tumor-bearing untrained animals. These data demonstrate that CD8+ T cells are metabolically altered by exercise in a manner that acts to improve their antitumoral efficacy.

Doxorubicin-induced skeletal muscle atrophy: Elucidating the underlying molecular pathways

Aim

Loss of skeletal muscle mass is a common clinical finding in cancer patients. The purpose of this meta‐analysis and systematic review was to quantify the effect of doxorubicin on skeletal muscle and report on the proposed molecular pathways possibly leading to doxorubicin‐induced muscle atrophy in both human and animal models.

Methods

A systematic search of the literature was conducted in PubMed, EMBASE, Web of Science and CENTRAL databases. The internal validity of included studies was assessed using SYRCLE’s risk of bias tool.

Results

Twenty eligible articles were identified. No human studies were identified as being eligible for inclusion. Doxorubicin significantly reduced skeletal muscle weight (ie EDL, TA, gastrocnemius and soleus) by 14% (95% CI: 9.9; 19.3) and muscle fibre cross‐sectional area by 17% (95% CI: 9.0; 26.0) when compared to vehicle controls. Parallel to negative changes in muscle mass, muscle strength was even more decreased in response to doxorubicin administration. This review suggests that mitochondrial dysfunction plays a central role in doxorubicin‐induced skeletal muscle atrophy. The increased production of ROS plays a key role within this process. Furthermore, doxorubicin activated all major proteolytic systems (ie calpains, the ubiquitin‐proteasome pathway and autophagy) in the skeletal muscle. Although each of these proteolytic pathways contributes to doxorubicin‐induced muscle atrophy, the activation of the ubiquitin‐proteasome pathway is hypothesized to play a key role. Finally, a limited number of studies found that doxorubicin decreases protein synthesis by a disruption in the insulin signalling pathway.

Conclusion

The results of the meta‐analysis show that doxorubicin induces skeletal muscle atrophy in preclinical models. This effect may be explained by various interacting molecular pathways. Results from preclinical studies provide a robust setting to investigate a possible dose‐response, separate the effects of doxorubicin from tumour‐induced atrophy and to examine underlying molecular pathways. More research is needed to confirm the proposed signalling pathways in humans, paving the way for potential therapeutic approaches.

Effects of Exercise on Chemotherapy Completion and Hospitalization Rates: The OptiTrain Breast Cancer Trial

BACKGROUND

Exercise during chemotherapy is suggested to provide clinical benefits, including improved chemotherapy completion. Despite this, few randomized controlled exercise trials have reported on such clinical endpoints. From the OptiTrain trial we previously showed positive effects on physiological and health-related outcomes after 16 weeks of supervised exercise in patients with breast cancer undergoing chemotherapy. Here, we examined the effects of exercise on rates of chemotherapy completion and hospitalization, as well as on blood cell concentrations during chemotherapy.

PATIENTS AND METHODS

Two hundred forty women scheduled for chemotherapy were randomized to 16 weeks of resistance and high-intensity interval training (RT-HIIT), moderate-intensity aerobic and high-intensity interval training (AT-HIIT), or usual care (UC). Outcomes included chemotherapy completion, hospitalization, hemoglobin, lymphocyte, thrombocyte, and neutrophil concentrations during chemotherapy.

RESULTS

No significant between-groups differences were found in the proportion of participants who required dose reductions (RT-HIIT vs. UC: odds ratio [OR], 1.08; AT-HIIT vs. UC: OR, 1.39), or average relative dose intensity of chemotherapy between groups (RT-HIIT vs. UC: effect size [ES], 0.08; AT-HIIT vs. UC: ES, -0.07). A significantly lower proportion of participants in the RT-HIIT group (3%) were hospitalized during chemotherapy compared with UC (15%; OR, 0.20). A significantly lower incidence of thrombocytopenia was found for both RT-HIIT (11%) and AT-HIIT (10%) versus UC (30%; OR, 0.27; OR, 0.27).

CONCLUSION

No beneficial effects of either RT-HIIT or AT-HIIT on chemotherapy completion rates were found. However, combined resistance training and high-intensity interval training were effective to reduce hospitalization rates, and both exercise groups had a positive effect on thrombocytopenia. These are important findings with potential positive implications for the health of women with breast cancer and costs associated with treatment-related complications.

IMPLICATIONS FOR PRACTICE

Completing the prescribed chemotherapy regimen is strongly associated with a good prognosis for patients with primary breast cancer. Despite this, treatment-induced side effects make it necessary to reduce or alter the treatment regimen and can also lead to hospitalization. Exercise during chemotherapy is suggested to provide clinical benefits, including improved chemotherapy completion. This study showed that combined resistance and high-intensity interval training during chemotherapy resulted in lower hospitalization rates and a lower incidence of thrombocytopenia in women with breast cancer undergoing chemotherapy. However, no beneficial effects of either exercise program on chemotherapy completion rates were found, which is in contrast to previous findings in this population. The findings reported in the current article have positive implications for the health of women with breast cancer and costs associated with treatment-related complications.

Influence of Hyperoxic-Supplemented High-Intensity Interval Training on Hemotological and Muscle Mitochondrial Adaptations in Trained Cyclists

Background: Hyperoxia (HYPER) increases O₂ carrying capacity resulting in a higher O₂ delivery to the working muscles during exercise. Several lines of evidence indicate that lactate metabolism, power output, and endurance are improved by HYPER compared to normoxia (NORM). Since HYPER enables a higher exercise power output compared to NORM and considering the O₂ delivery limitation at exercise intensities near to maximum, we hypothesized that hyperoxic-supplemented high-intensity interval training (HIIT) would upregulate muscle mitochondrial oxidative capacity and enhance endurance cycling performance compared to training in normoxia. Methods: 23 trained cyclists, age 35.3 ± 6.4 years, body mass 75.2 ± 9.6 kg, height 179.8 ± 7.9 m, and VO₂max 4.5 ± 0.7 L min^-1 performed 6 weeks polarized and periodized endurance training on a cycle ergometer consisting of supervised HIIT sessions 3 days/week and additional low-intensity training 2 days/week. Participants were randomly assigned to either HYPER (F_IO₂ 0.30; n = 12) or NORM (F_IO₂ 0.21; n = 11) breathing condition during HIIT. Mitochondrial respiration in permeabilized fibers and isolated mitochondria together with maximal and submaximal VO₂, hematological parameters, and self-paced endurance cycling performance were tested pre- and posttraining intervention. Results: Hyperoxic training led to a small, non-significant change in performance compared to normoxic training (HYPER 6.0 ± 3.7%, NORM 2.4 ± 5.0%; p = 0.073, ES = 0.32). This small, beneficial effect on the self-paced endurance cycling performance was not explained by the change in VO₂max (HYPER 1.1 ± 3.8%, NORM 0.0 ± 3.7%; p = 0.55, ES = 0.08), blood volume and hemoglobin mass, mitochondrial oxidative phosphorylation capacity (permeabilized fibers: HYPER 27.3 ± 46.0%, NORM 16.5 ± 49.1%; p = 0.37, ES = 3.24 and in isolated mitochondria: HYPER 26.1 ± 80.1%, NORM 15.9 ± 73.3%; p = 0.66, ES = 0.51), or markers of mitochondrial content which were similar between groups post intervention. Conclusions: This study showed that 6 weeks hyperoxic-supplemented HIIT led to marginal gain in cycle performance in already trained cyclists without change in VO₂max, blood volume, hemoglobin mass, mitochondrial oxidative phosphorylation capacity, or exercise efficiency. The underlying mechanisms for the potentially meaningful performance effects of hyperoxia training remain unexplained and may raise ethical questions for elite sport.

Two-year follow-up of the OptiTrain randomised controlled exercise trial

Purpose

The aim of this study was to determine if there were any differences in health-related outcomes and physical activity (PA) between the two OptiTrain exercise groups and usual care (UC), 2 years post-baseline.

Methods

The OptiTrain study was a three-arm randomised controlled trial comparing 16 weeks of concurrent aerobic high-intensity interval training (HIIT) and progressive resistance exercise (RT-HIIT) or concurrent HIIT and continuous moderate-intensity aerobic exercise (AT-HIIT) to UC in 206 patients with breast cancer undergoing chemotherapy. Eligible participants were approached 2 years following baseline to assess cancer-related fatigue, quality of life, symptoms, muscle strength, cardiorespiratory fitness, body mass, PA, sedentary behaviour, and sick leave.

Results

The RT-HIIT group reported lower total cancer-related fatigue, (− 1.37, 95% CI − 2.70, − 0.04, ES = − 0.06) and cognitive cancer-related fatigue (− 1.47, 95% CI − 2.75, − 0.18, ES = − 0.28), and had higher lower limb muscle strength (12.09, 95% CI 3.77, 20.40, ES = 0.52) than UC at 2 years. The AT-HIIT group reported lower total symptoms (− 0.23, 95% CI − 0.42, − 0.03, ES = − 0.15), symptom burden (− 0.30, 95% CI − 0.60, − 0.01, ES = − 0.19), and body mass − 2.15 (− 3.71, − 0.60, ES = − 0.28) than UC at 2 years.

Conclusion

At 2 years, the exercise groups were generally experiencing positive differences in cancer-related fatigue (RT-HIIT), symptoms (AT-HIIT), and muscle strength (RT-HIIT) to UC. The findings provide novel evidence that being involved in an exercise program during chemotherapy can have long-term benefits for women with breast cancer, but that strategies are needed to create better pathways to support patients to maintain physical activity levels.

Trial registration

Clinicaltrials.gov registration number: NCT02522260. Trial registered on 9 June 2015. https://clinicaltrials.gov/ct2/show/NCT02522260. Retrospectively registered.

Exercise training during chemotherapy preserves skeletal muscle fiber area, capillarization, and mitochondrial content in patients with breast cancer

Exercise has been suggested to ameliorate the detrimental effects of chemotherapy on skeletal muscle. The aim of this study was to compare the effects of different exercise regimens with usual care on skeletal muscle morphology and mitochondrial markers in patients being treated with chemotherapy for breast cancer. Specifically, we compared moderate-intensity aerobic training combined with high-intensity interval training (AT-HIIT) and resistance training combined with high-intensity interval training (RT-HIIT) with usual care (UC). Resting skeletal muscle biopsies were obtained pre- and postintervention from 23 randomly selected women from the OptiTrain breast cancer trial who underwent RT-HIIT, AT-HIIT, or UC for 16 wk. Over the intervention, citrate synthase activity, muscle fiber cross-sectional area, capillaries per fiber, and myosin heavy chain isoform type I were reduced in UC, whereas RT-HIIT and AT-HIIT were able to counteract these declines. AT-HIIT promoted up-regulation of the electron transport chain protein levels vs. UC. RT-HIIT favored satellite cell count vs. UC and AT-HIIT. There was a significant association between change in citrate synthase activity and self-reported fatigue. AT-HIIT and RT-HIIT maintained or improved markers of skeletal muscle function compared with the declines found in the UC group, indicating a sustained trainability in addition to the preservation of skeletal muscle structural and metabolic characteristics during chemotherapy. These findings highlight the importance of supervised exercise programs for patients with breast cancer during chemotherapy.-Mijwel, S., Cardinale, D. A., Norrbom, J., Chapman, M., Ivarsson, N., Wengström, Y., Sundberg, C. J., Rundqvist, H. Exercise training during chemotherapy preserves skeletal muscle fiber area, capillarization, and mitochondrial content in patients with breast cancer.

Highly favorable physiological responses to concurrent resistance and high-intensity interval training during chemotherapy: the OptiTrain breast cancer trial

Background

Advanced therapeutic strategies are often accompanied by significant adverse effects, which warrant equally progressive countermeasures. Physical exercise has proven an effective intervention to improve physical function and reduce fatigue in patients undergoing chemotherapy. Effects of high-intensity interval training (HIIT) in this population are not well established although HIIT has proven effective in other clinical populations. The aim of the OptiTrain trial was to examine the effects of concurrent resistance and high-intensity interval training (RT-HIIT) or concurrent moderate-intensity aerobic and high-intensity interval training (AT-HIIT), to usual care (UC) on pain sensitivity and physiological outcomes in patients with breast cancer during chemotherapy.

Methods

Two hundred and forty women were randomized to 16 weeks of RT-HIIT, AT-HIIT, or UC. Outcomes: cardiorespiratory fitness, muscle strength, body mass, hemoglobin levels, and pressure-pain threshold.

Results

Pre- to post-intervention, RT-HIIT (ES = 0.41) and AT-HIIT (ES = 0.42) prevented the reduced cardiorespiratory fitness found with UC. Handgrip strength (surgery side: RT-HIIT vs. UC: ES = 0.41, RT-HIIT vs. AT-HIIT: ES = 0.28; non-surgery side: RT-HIIT vs. UC: ES = 0.35, RT-HIIT vs. AT-HIIT: ES = 0.22) and lower-limb muscle strength (RT-HIIT vs. UC: ES = 0.66, RT-HIIT vs. AT-HIIT: ES = 0.23) were significantly improved in the RT-HIIT. Increases in body mass were smaller in RT-HIIT (ES = − 0.16) and AT-HIIT (ES = − 0.16) versus UC. RT-HIIT reported higher pressure-pain thresholds than UC (trapezius: ES = 0.46, gluteus: ES = 0.53) and AT-HIIT (trapezius: ES = 0.30).

Conclusion

Sixteen weeks of RT-HIIT significantly improved muscle strength and reduced pain sensitivity. Both exercise programs were well tolerated and were equally efficient in preventing increases in body mass and in preventing declines in cardiorespiratory fitness. These results highlight the importance of implementing a combination of resistance and high-intensity interval training during chemotherapy for women with breast cancer.

Adding high-intensity interval training to conventional training modalities: optimizing health-related outcomes during chemotherapy for breast cancer: the OptiTrain randomized controlled trial

Purpose

Exercise training is an effective and safe way to counteract cancer-related fatigue (CRF) and to improve health-related quality of life (HRQoL). High-intensity interval training has proven beneficial for the health of clinical populations. The aim of this randomized controlled trial was to compare the effects of resistance and high-intensity interval training (RT–HIIT), and moderate-intensity aerobic and high-intensity interval training (AT–HIIT) to usual care (UC) in women with breast cancer undergoing chemotherapy. The primary endpoint was CRF and the secondary endpoints were HRQoL and cancer treatment-related symptoms.

Methods

Two hundred and forty women planned to undergo chemotherapy were randomized to supervised RT–HIIT, AT–HIIT, or UC. Measurements were performed at baseline and at 16 weeks. Questionnaires included Piper Fatigue Scale, EORTC-QLQ-C30, and Memorial Symptom Assessment Scale.

Results

The RT–HIIT group was superior to UC for CRF: total CRF (p = 0.02), behavior/daily life (p = 0.01), and sensory/physical (p = 0.03) CRF. Role functioning significantly improved while cognitive functioning was unchanged for RT–HIIT compared to declines shown in the UC group (p = 0.04). AT–HIIT significantly improved emotional functioning versus UC (p = 0.01) and was superior to UC for pain symptoms (p = 0.03). RT–HIIT reported a reduced symptom burden, while AT–HIIT remained stable compared to deteriorations shown by UC (p < 0.01). Only RT–HIIT was superior to UC for total symptoms (p < 0.01).

Conclusions

16 weeks of resistance and HIIT was effective in preventing increases in CRF and in reducing symptom burden for patients during chemotherapy for breast cancer. These findings add to a growing body of evidence supporting the inclusion of structured exercise prescriptions, including HIIT, as a vital component of cancer rehabilitation.

Trial registration

Clinicaltrials.gov Registration Number: NCT02522260.

Cutaneous exposure to hypoxia does not affect skin perfusion in humans

AIM

Experiments have indicated that skin perfusion in mice is sensitive to reductions in environmental O₂ availability. Specifically, a reduction in skin-surface PO₂ attenuates transcutaneous O₂ diffusion, and hence epidermal O₂ supply. In response, epidermal HIF-1α expression increases and facilitates initial cutaneous vasoconstriction and subsequent nitric oxide-dependent vasodilation. Here, we investigated whether the same mechanism exists in humans.

METHODS

In a first experiment, eight males rested twice for 8 h in a hypobaric chamber. Once, barometric pressure was reduced by 50%, while systemic oxygenation was preserved by O₂ -enriched (42%) breathing gas (Hypoxia_Skin ), and once barometric pressure and inspired O₂ fraction were normal (Control₁ ). In a second experiment, nine males rested for 8 h with both forearms wrapped in plastic bags. O₂ was expelled from one bag by nitrogen flushing (Anoxia_Skin ), whereas the other bag was flushed with air (Control₂ ). In both experiments, skin blood flux was assessed by laser Doppler on the dorsal forearm, and HIF-1α expression was determined by immunohistochemical staining in forearm skin biopsies.

RESULTS

Skin blood flux during Hypoxia_Skin and Anoxia_Skin remained similar to the corresponding Control trial (P = 0.67 and P = 0.81). Immunohistochemically stained epidermal HIF-1α was detected on 8.2 ± 6.1 and 5.3 ± 5.7% of the analysed area during Hypoxia_Skin and Control₁ (P = 0.30) and on 2.3 ± 1.8 and 2.4 ± 1.8% during Anoxia_Skin and Control₂ (P = 0.90) respectively.

CONCLUSION

Reductions in skin-surface PO₂ do not affect skin perfusion in humans. The unchanged epidermal HIF-1α expression suggests that epidermal O₂ homoeostasis was not disturbed by Hypoxia_Skin /Anoxia_Skin , potentially due to compensatory increases in arterial O₂ extraction.

Optitrain: a randomised controlled exercise trial for women with breast cancer undergoing chemotherapy

BACKGROUND

Women with breast cancer undergoing chemotherapy suffer from a range of detrimental disease and treatment related side-effects. Exercise has shown to be able to counter some of these side-effects and improve physical function as well as quality of life. The primary aim of the study is to investigate and compare the effects of two different exercise regimens on the primary outcome cancer-related fatigue and the secondary outcomes muscle strength, function and structure, cardiovascular fitness, systemic inflammation, skeletal muscle gene activity, health related quality of life, pain, disease and treatment-related symptoms in women with breast cancer receiving chemotherapy. The second aim is to examine if any effects are sustained 1, 2, and 5 years following the completion of the intervention and to monitor return to work, recurrence and survival. The third aim of the study is to examine the effect of attendance and adherence rates on the effects of the exercise programme.

METHODS

This study is a randomised controlled trial including 240 women with breast cancer receiving chemotherapy in Stockholm, Sweden. The participants are randomly allocated to either: group 1: Aerobic training, group 2: Combined resistance and aerobic training, or group 3: usual care (control group). During the 5-year follow-up period, participants in the exercise groups will receive a physical activity prescription. Measurements for endpoints will take place at baseline, after 16 weeks (end of intervention) as well as after 1, 2 and 5 years.

DISCUSSION

This randomised controlled trial will generate substantial information regarding the effects of different types of exercise on the health of patients with breast cancer undergoing chemotherapy. We expect that dissemination of the knowledge gained from this study will contribute to developing effective long term strategies to improve the physical and psychosocial health of breast cancer survivors.

TRIAL REGISTRATION

OptiTrain - Optimal Training Women with Breast Cancer (OptiTrain), NCT02522260 ; Registration: June 9, 2015, Last updated version Feb 29, 2016. Retrospectively registered.

Physical Activity During and After Adjuvant Treatment for Breast Cancer: An Integrative Review of Women's Experiences

Background: In oncology, physical activity (PA) is recognized to improve psychological and physiological functions. Motivating women with breast cancer to sustain a physically active lifestyle is important for promoting positive health after diagnosis. To review and synthesize what is known about how women with breast cancer experience supervised and unsupervised PA during and after adjuvant treatment. PubMed, PsycINFO, and CINAHL were searched, yielding 994 citations. The final review included 17 articles published between 2004 and 2014 in English. The CASP (Critical Appraisal Skills Programme) instrument was used to appraise quality. Results: Exercise is experienced as a positive element with multiple benefits. However, maintaining a physically active lifestyle during and after chemotherapy is sometimes challenging. Reported benefits of PA include feeling empowered, and improving and reclaiming health. Facilitators to PA comprised exercising with peers and skilled instructors. Barriers included social factors and lack of information. Conclusions: Findings highlight the importance of incorporating PA programs from a patient experience perspective as routine treatment. Health care professionals play a crucial “gateway” role in providing information on implementation and benefits of PA. Providing support and educated advice about how to safely start or continue regular PA to minimize symptoms, reduce morbidity, and increase well-being during or after treatment is vital for women with breast cancer. Implications for Practice: Health care professionals need increased knowledge of the breast cancer patients’ perspectives on facilitators and barriers to PA during and after treatment, in order to provide sufficient support for women to stay physically active during a breast cancer illness.

Abstract 836: Effect of voluntary running on metastasis in a mouse model of breast cancer

Introduction: Emerging evidence states that regular physical exercise provides a risk reduction for breast cancer by approximately 25%. In addition, recent studies suggest that physical activity may also have an effect on recurrence and mortality. Mouse models are suitable tools to study anti-neoplastic mechanisms.

Aim: to evaluate the effect of voluntary running on tumor initiation, growth and metastasis in the Polyoma Middle T (PyMT) model of breast cancer.

Methods: PyMT mice were housed with access either to wirelessly recording running wheels or locked control wheels. Running distances and tumor volumes were recorded. At 12 weeks, mice were sacrificed. Mammary glands were histologically staged and pulmonary metastases were quantified. In a follow up study, pre-trained mice were injected intravenously with tumor cells derived from the PyMT model and after an additional 10 weeks of voluntary running, pulmonary metastases were quantified.

Results: PyMT mice ran significantly more than wildtype mice (6.4 vs 3.4 km/day). No significant effects of voluntary running on tumor- initiation, volume or stage were found. However, a trend for reduced metastasis was observed. After intravenous injections of tumor cells, runners had a significantly lower pulmonary metastasis frequency than non-runners.

Conclusion: In this aggressive breast cancer model, an average of 6 km/day of voluntary running did not induce any effect on tumor formation or growth. However, the findings suggest that physical activity has impact on the metastatic process.

Citation Format: Sara Mijwel, Helene Rundqvist, Carolin Lindholm, Carina Strell, Pernilla Roswall, Kristian Pietras, Randall S. Johnson, Arne Östman. Effect of voluntary running on metastasis in a mouse model of breast cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 836.

Abstract A65: Effect of voluntary running on metastasis in a mouse model of breast cancer

Introduction: Breast cancer is one of the most common neoplastic diseases. Emerging evidence states that regular physical exercise provides a risk reduction for breast cancer by approximately 25 %. In addition, recent studies suggest that physical activity may also have an effect on recurrence and mortality. Mouse models are suitable tools to study anti-neoplastic mechanisms.

Aim: To evaluate the effect of voluntary running on tumor initiation, growth and metastasis in mouse models of breast cancer.

Methods: From 4 weeks of age, MMTV-PyMT mice were housed with access either to wirelessly recording running wheels or locked control wheels. Running distances and tumor volumes were recorded. At 12 weeks, mice were sacrificed and mammary glands were histologically staged and pulmonary metastases were quantified. In a follow up study, pre-trained mice were injected intravenously with tumor cells derived from the PyMT model and after an additional 10 weeks of voluntary running, pulmonary metastases were quantified.

Results: PyMT mice ran significantly more than wildtype mice (6.4 vs 3.4 km/day). No significant effects of voluntary running on tumor- initiation, volume or stage were found. However, a trend for reduced metastasis was observed. Significant reductions in pulmonary metastasis frequency were found in runners after intravenous injections of tumor cells. Metastases of running mice displayed a reduced proliferation score.

Discussion: In this aggressive breast cancer model, an average of 6 km/day of voluntary running produces little effect on tumor formation and growth. However, the findings suggest that physical activity has impact on the metastatic process.

Citation Format: Helene Rundqvist, Sara Mijwel, Emil Ahlstedt, Carolin Lindholm, Carina Strell, Pernilla Roswall, Kristian Pietras, Randall Johnson, Arne Ostman. Effect of voluntary running on metastasis in a mouse model of breast cancer. [abstract]. In: Proceedings of the Twelfth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2013 Oct 27-30; National Harbor, MD. Philadelphia (PA): AACR; Can Prev Res 2013;6(11 Suppl): Abstract nr A65.

Effect of acute exercise on prostate cancer cell growth

Physical activity is associated with reduced risk of several cancers, including aggressive prostate cancer. The mechanisms mediating the effects are not yet understood; among the candidates are modifications of endogenous hormone levels. Long-term exercise is known to reduce serum levels of growth stimulating hormones. In contrast, the endocrine effects of acute endurance exercise include increased levels of mitogenic factors such as GH and IGF-1. It can be speculated that the elevation of serum growth factors may be detrimental to prostate cancer progression into malignancy. The incentive of the current study is to evaluate the effect of acute exercise serum on prostate cancer cell growth. We designed an exercise intervention where 10 male individuals performed 60 minutes of bicycle exercise at increasing intensity. Serum samples were obtained before (rest serum) and after completed exercise (exercise serum). The established prostate cancer cell line LNCaP was exposed to exercise or rest serum. Exercise serum from 9 out of 10 individuals had a growth inhibitory effect on LNCaP cells. Incubation with pooled exercise serum resulted in a 31% inhibition of LNCaP growth and pre-incubation before subcutaneous injection into SCID mice caused a delay in tumor formation. Serum analyses indicated two possible candidates for the effect; increased levels of IGFBP-1 and reduced levels of EGF. In conclusion, despite the fear of possible detrimental effects of acute exercise serum on tumor cell growth, we show that even the short-term effects seem to add to the overall beneficial influence of exercise on neoplasia.