Physical activity and advanced cancer: evidence of exercise-sensitive genes regulating prostate cancer cell proliferation and apoptosis

Levosimendan's Effects on Length-Dependent Activation in Murine Fast-Twitch Skeletal Muscle

Levosimendan's calcium sensitizing effects in heart muscle cells are well established; yet, its potential impact on skeletal muscle cells has not been evidently determined. Despite controversial results, levosimendan is still expected to interact with skeletal muscle through off-target sites (further than troponin C). Adding to this debate, we investigated levosimendan's acute impact on fast-twitch skeletal muscle biomechanics in a length-dependent activation study by submersing single muscle fibres in a levosimendan-supplemented solution. We employed our MyoRobot technology to investigate the calcium sensitivity of skinned single muscle fibres alongside their stress-strain response in the presence or absence of levosimendan (100 µM). While control data are in agreement with the theory of length-dependent activation, levosimendan appears to shift the onset of the 'descending limb' of active force generation to longer sarcomere lengths without notably improving myofibrillar calcium sensitivity. Passive stretches in the presence of levosimendan yielded over twice the amount of enlarged restoration stress and Young's modulus in comparison to control single fibres. Both effects have not been described before and may point towards potential off-target sites of levosimendan.

Crosstalk between Exercise and Immunotherapy: Current Understanding and Future Directions

Accumulated evidence highlights that exercise can modulate multiple cytokines, influencing transcriptional pathways, and reprogramming certain metabolic processes, ultimately promoting antitumor immunity and enhancing the efficacy of immune checkpoint inhibitors in cancer patients. Exploring the mechanisms behind this will, for one thing, help us uncover key factors and pathways in exercise-assisted cancer immunotherapy, offering more possibilities for future treatment methods. For another, it will support the development of more personalized and effective exercise prescriptions, thereby improving the prognosis of cancer patients.

Effects of Adjuvant Exercise and Nutrition Therapy on Muscle Fibre Biomechanics in Gastrointestinal Cancer Patients

Patients with aggressive cancer, e.g., gastrointestinal cancer, are prone (≥50% chance) to developing cancer cachexia (CC). Little is known about the effects of CC on the biomechanical function of muscle. A promising prevention strategy was found in the form of a multi-modal therapy combining mild resistance exercise (e.g., whole-body electro-myostimulation, WB-EMS) and a protein-rich diet. In a previous study of ours, this was effective in counteracting the loss of muscle mass, yet a systematic and comprehensive assessment of active and passive single muscle fibre functions was so far absent. This pilot study investigated the biomechanical function of single muscle fibres (rectus abdominis) from the biopsies of conventionally treated (pre-)cachectic cancer ((pre-)CC) patients (m = 9), those receiving the multi-modal therapy comprising WB-EMS training and protein-rich nutrition (m = 3), and a control group (m = 5). Our findings not only align with previous findings showing the absolute force loss in CC that is accelerated by atrophy but also speak in favour of a different, potentially energy- and Ca2+-homeostasis-related effect that compromises muscle contraction (F ~0.9 mN vs. F ~0.6 mN in control patients). However, myofibrillar Ca2+ sensitivity and the quality of contraction were unaltered (pCa50: 5.6-5.8). Single fibres from the (pre-)CC patients receiving WB-EMS training and protein supplementation were significantly more compliant (p < 0.001 at ≥130% of resting length L0). Those fibres displayed a similar softness to the ones from the control patients (axial compliance ~15 m/N at ≥130% L0), while single fibres from the patients with (developing) cachexia were significantly stiffer (axial compliance ~7 m/N, p < 0.001 at ≥130% L0). Adjuvant multi-modal therapy (WB-EMS training and nutritional support) contributes to maintaining the axial compliance of single fibres and potentially improves the quality of life for patients at risk of developing CC.

Revised contraindications for the use of non-medical WB-electromyostimulation. Evidence-based German consensus recommendations

Whole-body electromyostimulation has proven to be a highly effective alternative to conventional resistance-type exercise training. However, due to adverse effects in the past, very extensive contraindications have been put in place for the commercial, non-medical WB-EMS market. Considering recent positive innovations e.g., federal regulation, mandatory trainer education, revised guidelines, and new scientific studies on WB-EMS application, we believe that a careful revision of the very restrictive contraindications on WB-EMS is needed. This applies all the more because many cohorts with limited options for conventional exercise have so far been excluded. During a first meeting of an evidence-based consensus process, stakeholders from various backgrounds (e.g., research, education, application) set the priorities for revising the contraindications. We decided to focus on four categories of absolute contraindications: "Arteriosclerosis, arterial circulation disorders", "Diabetes mellitus" (DM), "Tumor and cancer" (TC), "Neurologic diseases, neuronal disorders, epilepsy". Based on scientific studies, quality criteria, safety aspects and benefit/risk assessment of the category, DM and TC were moved to the relative contraindication catalogue, while arteriosclerosis/arterial circulation disorders and neurologic diseases/neuronal disorders/epilepsy were still considered as absolute contraindications. While missing evidence suggests maintaining the status of neurologic diseases/neuronal disorders as an absolute contraindication, the risk/benefit-ratio does not support the application of WB-EMS in people with arteriosclerosis/arterial circulation diseases. Despite these very cautious modifications, countries with less restrictive structures for non-medical WB-EMS should consider our approach critically before implementing the present revisions. Considering further the largely increased amount of WB-EMS trials we advice regular updates of the present contraindication list.

Non-Athletic Cohorts Enrolled in Longitudinal Whole-Body Electromyostimulation Trials-An Evidence Map

Whole-body electromyostimulation (WB-EMS) can be considered as a time-efficient, joint-friendly, and highly customizable training technology that attracts a wide range of users. The present evidence map aims to provide an overview of different non-athletic cohorts addressed in WB-EMS research. Based on a comprehensive systematic search according to PRISMA, eighty-six eligible longitudinal trials were identified that correspond with our eligibility criteria. In summary, WB-EMS research sufficiently covers all adult age categories in males and females. Most cohorts addressed (58%) were predominately or exclusively overweight/obese, and in about 60% of them, diseases or conditions were inclusion criteria for the trials. Cohorts specifically enrolled in WB-EMS trials suffer from cancer/neoplasm (n = 7), obesity (n = 6), diabetes mellitus (n = 5), metabolic syndrome (n = 2), nervous system diseases (n = 2), chronic heart failure (n = 4), stroke (n = 1), peripheral arterial diseases (n = 2), knee arthrosis (n = 1), sarcopenia (n = 3), chronic unspecific low back pain (n = 4), and osteopenia (n = 3). Chronic kidney disease was an eligibility criterion in five WB-EMS trials. Finally, three studies included only critically ill patients, and two further studies considered frailty as an inclusion criterion. Of importance, no adverse effects of the WB-EMS intervention were reported. In summary, the evidence gaps in WB-EMS research were particular evident for cohorts with diseases of the nervous and cerebrovascular system.

A home-based lifestyle intervention program reduces the tumorigenic potential of triple-negative breast cancer cells

Translational research for the evaluation of physical activity habits and lifestyle modifications based on nutrition and exercise has recently gained attention. In this study, we evaluated the effects of serum samples obtained before and after a 12-week home-based lifestyle intervention based on nutrition and exercise in breast cancer survivors in terms of modulation of the tumorigenic potential of breast cancer cells. The home-based lifestyle intervention proposed in this work consisted of educational counselling on exercise and nutritional behaviors and in 12 weeks of structured home-based exercise. Triple-negative breast cancer cell line MDA-MB-231 was cultured in semi-solid medium (3D culture) with sera collected before (PRE) and after (POST) the lifestyle intervention program. Spheroid formation was evaluated by counting cell colonies after 3 weeks of incubation. Results show a slight but significant reduction of spheroid formation induced by serum collected POST in comparison to those obtained PRE. Moreover, statistical analyses aimed to find physiologic and metabolic parameters associated with 3D cell proliferation revealed the proliferative inducer IGF-1 as the only predictor of cell tumorigenic potential. These results highlight the importance of lifestyle changes for cancer progression control in a tertiary prevention context. Translational research could offer a useful tool to identify metabolic and physiological changes induced by exercise and nutritional behaviors associated with cancer progression and recurrence risk.

A single session of EMS training induces long-lasting changes in circulating muscle but not cardiovascular miRNA levels: a randomized crossover study

Electromyostimulation (EMS) is used to maintain or build skeletal muscle and to increase cardiopulmonary fitness. Only limited data on the molecular mechanisms induced by EMS are available and effects on circulating microRNAs (c-miRNAs) have not been reported. This study aimed to evaluate whether EMS induces long-term changes in muscle- and cardiovascular-specific c-miRNA levels. Twelve healthy participants (33.0 ± 12.0 yr, 7 women) performed a 20-min whole body EMS training and a time- and intensity-matched whole body circuit training (CT) in random order. Blood samples were drawn pre-/posttraining and at 1.5, 3, 24, 48, and 72 h to determine creatine kinase (CK) and miRNA-21-5p, -126-3p, -133a-3p, -146a-5p, -206-3p, -222-3p, and -499a-5p levels. Muscular exertion was determined using an isometric strength test, and muscle soreness/pain was assessed by questionnaire. EMS participants reported higher muscle soreness 48 and 72 h postexercise and mean CK levels after EMS increased compared with CT at 48 and 72 h (time × group P ≤ 0.01). The EMS session induced a significant elevation of myomiR-206 and -133a levels starting at 1.5 and 3 h after exercise. Both miRNAs remained elevated for 72 h with significant differences between 24 and 72 h (time × group P ≤ 0.0254). EMS did not induce changes in cardiovascular miRNAs and no elevation in any miRNA was detected following CT. Time-course analysis of muscle damage marker CK and c-miR-133a and -206 levels did not suggest a common scheme (P ≥ 0.277). We conclude that a single EMS session induces specific long-lasting changes of miR-206 and miR-133 involved in muscle proliferation and differentiation. A single EMS session does not affect primary cardiovascular miRNA-21-5p, -126-3p, -146a-5p, and -222-3p levels.NEW & NOTEWORTHY Our study describes the long-term effects of electromyostimulation (EMS) on circulating miRNA levels. The observed increase of functional myomiR-206 and -133a levels over 72 h suggests long-lasting effects on muscle proliferation and differentiation, whereas cardiovascular miRNAs appear unaffected. Our findings suggest that circulating miRNAs provide useful insight into muscle regeneration processes after EMS and may thus be used to optimize EMS training effects.

Genome-wide analysis of a cellular exercise model based on electrical pulse stimulation

Skeletal muscle communicates with other organs via myokines, which are secreted by muscle during exercise and exert various effects. Despite much investigation of the exercise, the underlying molecular mechanisms are still not fully understood. Here, we applied an in vitro exercise model in which cultured C2C12 myotubes were subjected to electrical pulse stimulation (EPS), which mimics contracting muscle. Based on the significantly up- and down-regulated genes in EPS, we constructed an in silico model to predict exercise responses at the transcriptional level. The in silico model revealed similarities in the transcriptomes of the EPS and exercised animals. Comparative analysis of the EPS data and exercised mouse muscle identified putative biomarkers in exercise signaling pathways and enabled to discover novel exercise-induced myokines. Biochemical analysis of selected exercise signature genes in muscle from exercised mice showed that EPS mimics in vivo exercise, at least in part, at the transcriptional level. Consequently, we provide a novel myokine, Amphiregulin (AREG), up-regulated both in vitro and in vivo, that would be a potential target for exercise mimetics.

Profile of Whole Body Electromyostimulation Training Users-A Pilot Study

(1) Introduction: Whole Body Electromyostimulation is a technological and time efficient personal training practiced all over the world. With the increase of practitioners in the last 10 years, the need to study more about practitioners has arisen, so this pilot study aims to trace a user profile of this method through the analysis of socio-demographic data for a better understand of the profile of people looking for this type of training to improve the effectiveness of the intervention and develop programs that are in accordance with the motivation of practitioners. (2) Methods: 270 users from 5 countries answered an online questionnaire with socio-demographic questions. Data were treated using descriptive statistics. Possible differences between sexes and between groups were analyzed by means of non-parametric statistical tests: Mann−Whitney U-test (continuous variables); in addition to studying possible dependence relationships and differences between proportions, using the Chi-square statistic with pairwise z-test using the Bonferroni correction (categorical variables). (3) Results: Middle-aged women are the main user of this type of training. The majority of WB-EMS users do another type of physical activity with significant difference between men and woman (p < 0.05) men are more active than women. Weight loss, health and wellness and muscle mass increase are the main goals of the WB-EMS users. There are significant differences in weight loss and rehabilitation between genders (p < 0.05). Women look much more than men to lose weight and men look more than women to rehabilitation. (4) Conclusions: The user profile is a physically active woman, aged 35−49 years, with normal weight and high educational level, who carries out twice weekly full body electrostimulation training with the goals of weight loss, health and/or wellness and muscle mass gain.

Muscle-Derived Cytokines Reduce Growth, Viability and Migratory Activity of Pancreatic Cancer Cells

Simple Summary

Pancreatic cancer (PC) is a highly fatal malignancy. A major reason for the poor prognosis of patients with PC is the insensitivity to most oncological treatment approaches. It is known that regular exercise reduces the cancer risk. We have already shown that serum from advanced prostate and colon cancer patients after exercise reduces growth and viability of cancer cells. The aim of this study was to identify exercise-induced cytokines in serum from patients with advanced-stage PC that regulate cancer cell proliferation and apoptosis. Our data suggest that a mild resistance exercise training in advanced PC patients induces the release of CXCL1, IL10 and CCL4 from contracting skeletal muscle. We demonstrate that these myokines inhibit growth and migration of PC cells, and induce PC cell death. With this report we provide new knowledge on the cancer-protective function of exercise in PC. Our data strongly support sport therapies for cancer patients.

Abstract

The evidence that regular physical exercise reduces the risk of developing cancer is well described. However, the interaction between physical exercise and cancer is not fully clarified yet. Several myokines released by skeletal muscle appear to have a direct anti-tumour function. There are few data on myokine secretion after exercise in patients with advanced tumours. Pancreatic cancer (PC) is a very aggressive and usually fatal cancer. To investigate the effects of exercise in PC, the blood of advanced-stage PC patients was analysed after 12 weeks of resistance training using whole-body electromyostimulation. After the 12-week training period, the patient serum inhibited the proliferation and the motility of PC cells and enhanced PC cell apoptosis. The impact of exercise training was also investigated in an exercise-mimicking in vitro model using electric pulse stimulation of human myotubes and revealed similar anti-tumour effects on PC cells, clearly indicating direct cancer-protective properties of activated skeletal muscle. Protein and gene expression analyses in plasma from exercise-trained patients and in myotube cultures after in vitro exercise showed that interleukin 10 (IL10), C-X-C motif ligand 1 (CXCL1) and C-C motif chemokine ligand 4 (CCL4) are myokines released from activated skeletal muscle. In accordance with the effects of serum from exercise-trained patients, the supplementation with recombinant IL10, CXCL1 and CCL4 impaired growth and migration of PC cells. Treatment of PC cells with these myokines upregulated caspase 3/7 expression and the cleavage of poly(ADP-ribose) polymerase, leading to enhanced PC cell death. The identification of myokines with anti-tumour properties in advanced-stage PC patients after exercise opens a new perspective in supportive therapy with sports and exercise for cancer patients.

Anti-carcinogenic effects of exercise-conditioned human serum: evidence, relevance and opportunities

Regular physical activity reduces the risk of several site-specific cancers in humans and suppresses tumour growth in animal models. The mechanisms through which exercise reduces tumour growth remain incompletely understood, but an intriguing and accumulating body of evidence suggests that the incubation of cancer cells with post-exercise serum can have powerful effects on key hallmarks of cancer cell behaviour in vitro. This suggests that exercise can impact tumour biology through direct changes in circulating proteins, RNA molecules and metabolites. Here, we provide a comprehensive narrative overview of what is known about the effects of exercise-conditioned sera on in vitro cancer cell behaviour. In doing so, we consider the key limitations of the current body of literature, both from the perspective of exercise physiology and cancer biology, and we discuss the potential in vivo physiological relevance of these findings. We propose key opportunities for future research in an area that has the potential to identify key anti-oncogenic protein targets and optimise physical activity recommendations for cancer prevention, treatment and survivorship.