Resistance Exercise and Skeletal Muscle-Related Outcomes in Patients with Cancer: A Systematic Review.

BACKGROUND: Skeletal muscle loss is prevalent throughout the cancer continuum and correlates with morbidity and mortality. Resistance exercise has been trialed to mitigate skeletal muscle loss. This systematic review summarizes and qualitatively synthesizes the effects of resistance exercise on muscle-related outcomes in adult cancer populations, including skeletal muscle mass, performance and muscle-related biomarkers. METHODS: The systematic review protocol was developed in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). We searched electronic databases including AMED, CENTRAL, CINAHL, CIRRIE, EMBASE, MEDLINE, PEDro, REHABDATA, Scopus, and SPORTDiscus (from inception to December 2021).We included randomized controlled trials that investigated the effects of resistance exercise on muscle-related outcomes in adult cancer populations. Interventions that involved any resistance exercise were included. Muscle-related outcomes were categorized as skeletal muscle mass (e.g., lean mass, appendicular muscle mass), muscle performance (e.g., muscle strength, physical function), and muscle-related biomarkers (e.g., muscle cells, metabolic/inflammatory markers). Risk of bias (RoB) was assessed using the Cochrane ROB tool. RESULTS: 02 studies from 101 randomized controlled trials were included. The majority of studies focused on breast cancer (46%) and those who completed treatment (43%). Resistance exercise interventions were largely 3-4 months long (48%), combined with aerobic exercise (56%), at a vigorous intensity (25%), and in-person/supervised settings (57%). Among the studies that assessed muscle mass, performance, and biomarkers (n = 42, 83, and 22, respectively), resistance exercise interventions improved upper/lower body or appendicular muscle mass (67-100%), muscle strength (61-68%), and physical function (74-100%). Most biomarkers did not show significant changes (75-100%) or showed inconsistent results. CONCLUSIONS: Generally, resistance exercise had positive effects on skeletal muscle mass and performance with an absence of negative effects compared to controls. Our findings demonstrated that resistance exercise may be an effective strategy to attenuate deterioration or exert improvements in muscle mass and performance outcomes.

Penicillin Binding Protein 7/8 Is a Potential Drug Target in Carbapenem-Resistant Acinetobacter baumannii.

Limited therapeutic options dictate the need for new classes of antimicrobials active against carbapenem-resistant Acinetobacter baumannii. Presented data confirm and extend penicillin binding protein 7/8 (PBP 7/8) as a high-value target in the CR A. baumannii strain HUMC1. PBP 7/8 was essential for optimal growth/survival of HUMC1 in ex vivo human ascites and in a rat subcutaneous abscess model; in a mouse pneumonia model, the absence of PBP 7/8 decreased lethality 11-fold. The loss of PBP 7/8 resulted in increased permeability, sensitivity to complement, and lysozyme-mediated bactericidal activity. These changes did not appear to be due to alterations in the cellular fatty acid composition or capsule production. However, a decrease in lipid A and an increase in coccoidal cells and cell aggregation were noted. The compromise of the stringent permeability barrier in the PBP 7/8 mutant was reflected by an increased susceptibility to several antimicrobials. Importantly, expression of ampC was not significantly affected by the loss of PBP 7/8 and serial passage of the mutant strain in human ascites over 7 days did not yield revertants possessing a wild-type phenotype. In summary, these data and other features support PBP 7/8 as a high-value drug target for extensively drug-resistant and CR A. baumannii. Our results guide next-stage studies; the determination that the inactivation of PBP 7/8 results in an increased sensitivity to lysozyme enables the design of a high-throughput screening assay to identify small molecule compounds that can specifically inhibit PBP 7/8 activity.

Efficacy of resistive exercise on skeletal muscle-related outcomes in cancer survivors: a systematic review protocol.

BACKGROUND: Symptom burden and adverse treatment effects can negatively impact physical function, health-related outcomes, and quality of life in cancer survivors. Resistive exercise that improves skeletal muscle function can ameliorate these complications, but the central role of the skeletal muscle in mediating improvements in patient-related outcomes has not been explored. This protocol describes the rationale and methods for a systematic review that aims to determine the effects of resistive exercise on the skeletal muscle hypertrophy, muscle performance, and muscle-related biomarkers in cancer survivors. METHODS: A systematic review will be conducted on peer-reviewed randomized controlled trials (RCTs) that employ resistive exercise interventions for cancer survivors. The following electronic databases will be searched: AMED, CENTRAL, CINAHL, CIRRIE, EMBASE, MEDLINE, PEDro, REHABDATA, Scopus, and SPORTDiscus. Studies will be considered for inclusion if they present quantitative data in adult cancer survivors on skeletal muscle characteristics (e.g., muscle mass), muscle performance (e.g., strength), or skeletal muscle-related biomarkers (e.g., myocellular satellite cells). Secondary outcomes will be physical function (e.g., stair climb) and patient-reported outcomes (e.g., fatigue). Data will be reported through a narrative that describes study design, participants, interventions, and outcome characteristics. DISCUSSION: This systematic review will help clarify the influence of resistive exercise on factors relating to the skeletal muscle in adult cancer survivors. Findings may provide insight into optimal exercise selection for evidence-based practice. SYSTEMATIC REVIEW REGISTRATION: PROSPERO: #277791 [under review].

Effect of exercise on tumor markers - Is exercise anti-tumorigenic in humans?: A scoping review of preliminary clinical investigations.

It has been increasingly conceptualized that exercise may be able to suppress cancer progression itself based on the preclinical evidence suggesting various mechanisms. The challenges exist in investigating the effects of exercise on tumor progression in human settings. Circulating or tissue-driven tumor markers can be a useful and cost-effective tool in monitoring the progression of some cancers. This scoping review summarized the current evidence on the use of tumor markers in clinical exercise oncology trials. A total of 14 studies were identified, and tumor markers included prostate-specific antigen for prostate cancer, carcinoembryonic antigen and circulating tumor cells for colorectal cancer, and Ki-67 for breast cancer. Treatment settings and exercise prescriptions were highly heterogeneous, while most studies did not find significant exercise-mediated effects on tumor markers. Nevertheless, we provide an insight into the utility and considerations in using tumor markers in clinical exercise oncology research.

The Effect of Exercise and Nutritional Interventions on Body Composition in Patients with Advanced or Metastatic Cancer: A Systematic Review.

Advanced and metastatic cancers significantly alter body composition, leading to decreased lean mass and variable effects on fat mass. These effects on body composition are associated with significant physical dysfunction and poor prognosis in patients with cancer. Whilst exercise and nutritional interventions are likely to be of benefit in counteracting these effects, relatively little is known about using such interventions in patients with advanced or metastatic cancer. Therefore, in this systematic review we examine the effect of exercise and combined exercise and nutritional interventions on lean mass and fat mass among patients diagnosed with advanced or metastatic cancer. Following PRISMA guidelines, we identified 20 articles from PubMed, EMBASE, CINAHL, Cochrane CENTRAL, PEDro, SPORTDiscus, and REHABDATA. Overall, advanced or metastatic cancer populations comprising of mixed cancer types were most commonly examined (n = 8) with exercise or combined exercise and nutritional interventions being well-tolerated with few adverse effects. Both intervention approaches may preserve lean mass, while only combined interventions may lead to alterations in fat mass. However, further exercise and nutritional studies are needed to definitively understand their effects on body composition. As exercise and nutrition-related research continues in this understudied population, the knowledge gained will help guide supportive clinical treatments.

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.