Association of Body Composition With Survival and Treatment Efficacy in Castration-Resistant Prostate Cancer

Voluntary Exercise Attenuates Tumor Growth in a Preclinical Model of Castration-Resistant Prostate Cancer

Purpose

To examine the effects of voluntary exercise training on tumor growth and explore the underlying intratumoral molecular pathways and processes responsible for the beneficial effects of VWR on tumor initiation and progression in a mouse model of Castration-Resistant Prostate Cancer (CRPC).

Methods

Male immunodeficient mice (SCID) were castrated and subcutaneously inoculated with human CWR-22RV1 cancer cells to construct CRPC xenograft model before randomly assigned to either voluntary wheel running (VWR) or sedentary (SED) group (n=6/group). After three weeks, tumor tissues were collected. Tumor size was measured and calculated. mRNA expression of markers of DNA replication, Androgen Receptor (AR) signaling, and mitochondrial dynamics was determined by RT-PCR. Protein expression of mitochondrial content and dynamics was determined by western blotting. Finally, RNA-sequencing analysis was performed in the tumor tissues.

Results

Voluntary wheel running resulted in smaller tumor volume at the initial stage and attenuated tumor progression throughout the time course (P < 0.05). The reduction of tumor volume in VWR group was coincided with lower mRNA expression of DNA replication markers ( MCM2 , MCM6 , and MCM7 ), AR signaling ( ELOVL5 and FKBP5 ) and regulatory proteins of mitochondrial fission (Drp1 and Fis1) and fusion (MFN1 and OPA1) when compared to the SED group (P<0.05). More importantly, RNA sequencing data further revealed that pathways related to pathways related to angiogenesis, extracellular matrix formation and endothelial cell proliferation were downregulated.

Conclusions

Three weeks of VWR was effective in delaying tumor initiation and progression, which coincided with reduced transcription of DNA replication, AR signaling targets and mitochondrial dynamics. We further identified reduced molecular pathways/processes related to angiogenesis that may be responsible for the delayed tumor initiation and progression by VWR.

The impact of sarcopenia on clinical outcomes in men with metastatic castrate-resistant prostate cancer

INTRODUCTION

Sarcopenia is common in men with metastatic castrate-resistant prostate cancer (mCRPC) and has been largely assessed opportunistically through computed-tomography (CT) scans, excluding measures of muscle function. Therefore, the impact of a comprehensive assessment of sarcopenia on clinical outcomes in men with mCRPC is poorly understood. The objectives of this study were to comprehensively assess sarcopenia through CT scans and measures of muscle function and examine its impact on severe treatment toxicity, time to first emergency room (ER) visit, disease progression, and overall mortality in men initiating chemotherapy or androgen receptor-targeted axis (ARAT) therapy for mCRPC.

METHODS

This was a secondary analysis of a prospective observational study of men with mCRPC at the Princess Margaret Cancer Centre between July 2015-May 2021. Participants were classified as sarcopenic if they had CT-based low muscle mass or low muscle density, a grip strength and gait speed score of <35.5kg and <0.8m/s, respectively, prior to treatment initiation. The impact of sarcopenia on severe treatment toxicity was assessed using multivariable logistic regression. Multivariable Cox regression models were used to determine the impact of sarcopenia on risk of visiting the ER, prostate-specific antigen progression, radiographic progression, and overall mortality.

RESULTS

A total of 110 men (mean age: 74.6) were included in the analysis. At baseline, 30 (27.3%) were classified as sarcopenic. Sarcopenia was a significant predictor of severe toxicity (aOR = 6.26, 95%CI = 1.17-33.58, P = 0.032) and ER visits (aHR = 4.41, 95%CI = 1.26-15.43, p = 0.020) in men initiating ARAT but not in men initiating chemotherapy. Sarcopenia was also a predictor of radiographic progression (aHR = 2.39, 95%CI = 1.06-5.36, p = 0.035) and overall mortality (aHR = 2.44, 95%CI = 1.17-5.08, p = 0.018) regardless of treatment type.

CONCLUSIONS

Baseline sarcopenia predicts radiographic progression and overall mortality in men with mCRPC regardless of the type of treatment and may also predict severe treatment toxicity and ER visits in men initiating ARAT.

Voluntarily wheel running inhibits the growth of CRPC xenograft by inhibiting HMGB1 in mice

INTRODUCTION

Exercise has been proved to reduce the risk of recurrence and mortality of cancer. Emerging evidence indicated that exercise may regulate both systematical and local metabolism, immunity and other ways. Although the role of exercise in inhibiting castration-resistant prostate cancer is well established, the underlying mechanism remains unclear.

METHOD

Twenty C57BL/6 male mice were used to construct CRPC xenograft models and randomly divided into exercise group (n = 10) and control group (n = 10). After exercised with voluntarily wheel running for 21 days, the mice were sacrificed and the tumor tissues and serum were collected. TUNEL staining was used to detect the apoptosis of tumor cells. The expression of PI3K signal pathway and apoptosis related proteins were detected by Western blot. The expression of AR and HMGB1 were examined by Western blot and Immunohistochemical staining. IFN-γ, TNF-α, TGF-β, IL-4, IL-6, IL-10 in serum was examined using ELISA kits.

RESULTS

Voluntarily wheel running inhibited the growth of CRPC xenografts, inhibited the proliferation of tumor cells and promoted the apoptosis of tumor cells. HMGB1 levels in serum and tumor tissues were significantly reduced after exercise, which enhanced local immunity by inducing more leukocyte infiltration and inhibited systemic inflammatory response by regulating cytokines.

CONCLUSION

Voluntary wheel running can down-regulate the expression of HMGB1 in serum and transplanted tumor tissues, inhibit proliferation and promote apoptosis of tumor cells, enhance immune cell infiltration and systemic inflammatory response, and regulate local anti-tumor effects in tumor microenvironment.

Associations of Total Body Fat Mass and Skeletal Muscle Index with All-Cause and Cancer-Specific Mortality in Cancer Survivors

Purpose: The importance of body composition on cancer outcomes is of great clinical interest. Measures of body composition that differentiate fat mass from skeletal muscle mass can help redefine our understanding of body composition for cancer survival. We investigated whether the risk of all-cause and cancer-specific mortality differ by levels of total fat mass and sarcopenia status in cancer survivors. Our secondary aim was a subgroup analysis assessing the role of race within these associations. Methods: Participants included 1682 adult cancer survivors who had undergone a dual-energy X-ray absorptiometry (DXA) examination to measure body composition, from the 1999-2006 and 2011-2018 National Health and Nutrition Examination Survey (NHANES). Total fat mass was categorized into tertiles (we assessed high vs. low tertiles), and sarcopenia was considered as having an appendicular skeletal muscle mass index less than 7.26 kg/m2 for males and less than 5.45 kg/m2 for females. Multivariable Cox proportional hazard models estimated the adjusted hazard ratio (aHR) and 95% confidence interval (CI). Results: The mean age of study participants was 61.9 years, and they were followed up for an average of 9.67 years. The prevalence of sarcopenia was 25.0% (N = 304), and 33.4% (N = 561) had a high total fat mass. Participants with a higher fat mass (aHR = 1.30, 95% CI = 1.06-1.61) and with sarcopenia (aHR = 1.51, 95% CI = 1.22-1.88) had a 30% and 51% increased risk of all-cause mortality compared to participants with a low fat mass and with no sarcopenia, respectively. Further, sarcopenia (aHR = 1.74, 95% CI = 1.23-2.29) was associated with a higher risk of cancer-specific mortality in cancer survivors. The association between sarcopenia and all-cause mortality was twice as strong in Black people (aHR = 2.99, 95% CI = 1.39-6.06) compared to White people (aHR = 1.53, 95% CI = 1.19-1.95). Conclusions: Our findings show the opposing relations of fat mass and appendicular skeletal muscle mass index with mortality in a national sample of cancer survivors, and that the relationships may differ by race. These results emphasize the importance of maintaining a healthy body composition among cancer survivors.

Relationships of body composition and adipocytokines with outcomes in metastatic castration-resistant prostate cancer patients receiving docetaxel chemotherapy

We evaluated the relationships of body composition and serum adipocytokine levels with progression-free survival (PFS) and overall survival (OS) in metastatic castration-resistant prostate cancer (mCRPC) patients receiving docetaxel. The medical records of mCRPC patients who received docetaxel between January 2011 and December 2015 at Fudan University Shanghai Cancer Center (Shanghai, China) were reviewed. The following body composition parameters were calculated using computed tomography: skeletal muscle index (SMI), visceral adipose tissue index (VATI), and subcutaneous adipose tissue index (SATI). Pretreatment serum adipocytokine levels, including interleukin 6, insulin, leptin, monocyte chemoattractant protein-1, adiponectin, and resistin, were measured using the multiplex bead-based immunoassays. Cox regression and Kaplan-Meier methods were used for survival analyses. Of the 453 mCRPC patients initially identified, 105 were included in the analysis. High VATI group patients had longer PFS (median, 10 months vs 7 months, P = 0.008) and OS (median, 24 months vs 15 months, P = 0.017), compared with low VATI group patients. SMI and SATI were not significantly associated with PFS or OS. Of the six detected adipocytokines, only leptin was associated with mCRPC prognosis. High leptin group patients had shorter PFS (median, 7 months vs 12 months, P = 0.0018) and OS (median, 17 months vs 22 months, P = 0.042), compared with low leptin group patients. Multivariate analysis showed that a high VATI was an independent protective factor for PFS and OS, while a high leptin level was an independent risk factor for PFS and OS. Therefore, VATI and serum leptin levels could provide important information concerning mCRPC prognosis.

Prognostic Impact of Sarcopenia in Patients with Advanced Prostate Carcinoma: A Systematic Review

Prostate cancer (PCa) is the second most common cancer in men and the fifth leading cause of death from cancer. The possibility of sarcopenia being a prognostic factor in advanced PCa patients has recently become a subject of interest. The aim of the present study was to evaluate the prognostic value of sarcopenia in advanced prostate carcinoma. A systematic review was conducted in Medline, EMBASE, and Web of Science (March, 2021). The quality of studies was assessed using the Quality in Prognosis Studies tool. Meta-analyses for overall, cancer-specific, and progression-free survival were performed. Nine studies (n = 1659) were included. Sarcopenia was borderline associated with a shorter overall survival (HR = 1.20, 95% CI: 1.01, 1.44, P = 0.04, I2 = 43%) but was significantly associated with progression-free survival (HR = 1.61, 95% CI: 1.26, 2.06, P < 0.01; k = 3; n = 588). Available evidence supports sarcopenia as an important prognostic factor of progression-free survival in patients with advanced PCa. However, sarcopenia has a weak association with a shorter overall survival. The evidence on the role of sarcopenia in prostate-cancer-specific survival is insufficient and supports the need for further research. Patient summary: The literature was reviewed to determine whether the loss of muscle mass (sarcopenia) affects the survival in patients with advanced PCa. Patients with advanced PCa and sarcopenia were found to have a shorter progression-free survival (the length of time during and after treatment of a cancer that the patient lives with the disease but it does not get worse), but sarcopenia did not have much influence on the overall survival and cancer-specific survival (the length of time from either the date of diagnosis or the start of treatment to the date of death due to the cancer).

MRI-measured adipose features as predictive factors for detection of prostate cancer in males undergoing systematic prostate biopsy: a retrospective study based on a Chinese population

In this study, we retrospectively evaluated the data of 901 men undergoing ultrasonography-guided systematic prostate biopsy between March 2013 and May 2022. Adipose features, including periprostatic adipose tissue (PPAT) thickness and subcutaneous fat thickness, were measured using MRI before biopsy. Prediction models of all PCa and clinically significant PCa (csPCa) (Gleason score higher than 6) were established based on variables selected by multivariate logistic regression and prediction nomograms were constructed. Patients with PCa had higher PPAT thickness (4.64 [3.65-5.86] vs. 3.54 [2.49-4.51] mm, p < 0.001) and subcutaneous fat thickness (29.19 [23.05-35.95] vs. 27.90 [21.43-33.93] mm, p = 0.013) than those without PCa. Patients with csPCa had higher PPAT thickness (4.78 [3.80-5.88] vs. 4.52 [3.80-5.63] mm, p = 0.041) than those with non-csPCa. Adding adipose features to the prediction models significantly increased the area under the receiver operating characteristics curve for the prediction of all PCa (0.850 vs. 0.819, p < 0.001) and csPCa (0.827 vs. 0.798, p < 0.001). Based on MRI-measured adipose features and clinical parameters, we established two nomograms that were simple to use and could improve patient selection for prostate biopsy in Chinese population.

Adiposity and cancer survival: a systematic review and meta-analysis

PURPOSE

The increasing availability of clinical imaging tests (especially CT and MRI) that directly quantify adipose tissue has led to a rapid increase in studies examining the relationship of visceral, subcutaneous, and overall adiposity to cancer survival. To summarize this emerging body of literature, we conducted a systematic review and meta-analysis of imaging-measured as well as anthropometric proxies for adipose tissue distribution and cancer survival across a wide range of cancer types.

METHODS

Using keywords related to adiposity, cancer, and survival, we conducted a systematic search of the literature in PubMed and MEDLINE, Embase, and Web of Science Core Collection databases from database inception to 30 June 2021. We used a random-effect method to calculate pooled hazard ratios (HR) and corresponding 95% confidence intervals (CI) within each cancer type and tested for heterogeneity using Cochran's Q test and the I2 test.

RESULTS

We included 203 records for this review, of which 128 records were utilized for quantitative analysis among 10 cancer types: breast, colorectal, gastroesophageal, head and neck, hepatocellular carcinoma, lung, ovarian, pancreatic, prostate, and renal cancer. We found that imaging-measured visceral, subcutaneous, and total adiposity were not significantly associated with increased risk of overall mortality, death from primary cancer, or cancer progression among patients diagnosed with these 10 cancer types; however, we found significant or high heterogeneity for many cancer types. For example, heterogeneity was similarly high when the pooled HRs (95% CI) for overall mortality associated with visceral adiposity were essentially null as in 1.03 (0.55, 1.92; I2 = 58%) for breast, 0.99 (0.81, 1.21; I2 = 71%) for colorectal, versus when they demonstrated a potential increased risk 1.17 (0.85, 1.60; I2 = 78%) for hepatocellular carcinoma and 1.62 (0.90, 2.95; I2 = 84%) for renal cancer.

CONCLUSION

Greater adiposity at diagnosis (directly measured by imaging) is not associated with worse survival among cancer survivors. However, heterogeneity and other potential limitations were noted across studies, suggesting differences in study design and adiposity measurement approaches, making interpretation of meta-analyses challenging. Future work to standardize imaging measurements and data analyses will strengthen research on the role of adiposity in cancer survival.

Body composition change during neoadjuvant chemotherapy for breast cancer

Background

Sarcopenia is receiving attention in oncology as a predictor of increased chemotherapy toxicities. Research into body composition change during neoadjuvant chemotherapy for breast cancer is both urgently needed and generally lacking. This study assessed sarcopenia prevalence before and after neoadjuvant chemotherapy using CT imaging, evaluated body composition changes during neoadjuvant chemotherapy, and determined predictors of sarcopenia status after neoadjuvant chemotherapy for breast cancer.

Materials and Methods

In this retrospective, descriptive study, we used data collected from 2017 to 2020 to measure body composition parameters on cross-sectional CT slices for 317 Korean women with breast cancer patients before and at completion of neoadjuvant chemotherapy. Changes in skeletal muscle index, visceral fat index, subcutaneous fat index, and sarcopenia were assessed and correlated, and multivariate logistic regression was conducted to identify predictive factors associated with sarcopenia status at completion of neoadjuvant chemotherapy.

Results

Of the 80 breast cancer patients (25.2%) who had sarcopenia before beginning neoadjuvant chemotherapy, 64 (80.0%) retained their sarcopenia status after chemotherapy. Weight, body mass index, body surface area, and visceral fat index showed significant increases after neoadjuvant chemotherapy; notably, only skeletal muscle index significantly decreased, showing a reduction of 0.44 cm2/m2 (t (316) = 2.15, p &lt;.5). Lower skeletal muscle index at baseline was associated with greater loss of muscle mass during neoadjuvant chemotherapy (r = −.24, p &lt;.001). Multivariate logistic regression showed that baseline sarcopenia status was the only significant predictor of sarcopenia status after neoadjuvant chemotherapy (p &lt;.001). Specifically, the log odds of sarcopenia after neoadjuvant chemotherapy were 3.357 higher in the baseline sarcopenia group than in the group without baseline sarcopenia (β = 3.357, p &lt;.001).

Conclusion

Sarcopenia during neoadjuvant chemotherapy can be obscured by an increasing proportion of fat in body composition if clinical assessment focuses on only body mass index or body surface area rather than muscle mass. For breast cancer patients who have sarcopenia when they begin neoadjuvant chemotherapy, the risk of muscle mass loss during treatment is alarmingly high. To reduce masking of muscle mass loss during treatment, comprehensive evaluation of body composition, beyond body surface area assessment, is clearly needed.

Interventions for Improving Body Composition in Men with Prostate Cancer: A Systematic Review and Network Meta-analysis

PURPOSE

To perform a systematic review and network meta-analysis to investigate the most effective intervention for improving body composition outcomes in prostate cancer patients during or after treatment.

METHODS

A systematic search was undertaken in multiple databases from inception to December 2020. Randomized clinical trials examining the effects of exercise/physical activity and/or nutrition interventions on body composition and body weight measures in prostate cancer patients were included. The primary endpoints were both whole-body and regional fat mass and lean mass measures, with body weight and BMI as secondary outcomes. A frequentist random-effects network meta-analysis was undertaken to examine the clustering effect of intervention modalities or control groups on the outcomes of interest. The study protocol is publicly available on PROSPERO (CRD42020202339).

RESULTS

Fifty articles describing 47 trials (n = 3207) were included. Resistance training and combined resistance and aerobic exercise were the most effective interventions to reduce body fat percentage (-0.9%; 95% confidence interval [CI], -1.4% to -0.3%) and fat mass (-0.5 kg; 95% CI, -0.9 to -0.1 kg), respectively. For whole-body and regional lean mass, combined resistance and aerobic exercise + healthy diet (0.6 kg; 95% CI, 0.1 to 1.0 kg) and resistance training alone (0.7 kg, 95% CI: 0.4 to 1.0 kg) were the best intervention, respectively. A low-fat diet was the most effective for reducing body weight immediately after or at follow-up, while no intervention promoted significant reductions in BMI.

CONCLUSIONS

These results indicate that a resistance-based exercise program alone or combined with a general healthy diet are the most effective interventions for improving overall body composition in men with prostate cancer.

Associations of fat and muscle mass with overall survival in men with prostate cancer: a systematic review with meta-analysis

BACKGROUND

To systematically review and analyse the associations between fat and muscle mass measures with overall survival in men with prostate cancer.

METHODS

A systematic search was conducted in CINAHL, Cochrane Library, EMBASE, PubMed, and Web of Science databases from inception to December 2020, while abstracts from the American Society of Clinical Oncology (ASCO), Clinical Oncology Society of Australia (COSA), and the American College of Sports Medicine (ACSM) conferences were searched from 2014 to 2020. Eligible articles examined the association of body composition measures, such as fat mass (e.g., fat mass, visceral adipose tissue (VAT), subcutaneous adipose tissue (SAT), and VAT/SAT) and muscle mass measures, with overall survival in prostate cancer patients at any treatment stage. The primary endpoint was overall survival. Random-effect meta-analysis was conducted for studies reporting multivariable or univariable analysis assessing the associations of fat mass measures (i.e., fat mass, VAT, SAT, VAT/SAT) and muscle mass measures with overall survival.

RESULTS

Sixteen cohort studies that comprised 4807 men with prostate cancer were included. Total adiposity (hazard ratio (HR) 0.98, 95% CI: 0.75-1.28, p = 0.888) and VAT (HR 1.03, 95% CI: 0.74-1.43, p = 0.873) were not significantly associated with overall survival, while higher subcutaneous adipose tissue levels were associated with higher survival (HR 0.68, 95% CI: 0.54-0.84, p = 0.001). Greater mortality risk was found in patients with localised (HR 1.91, 95% CI: 1.40-2.62, p < 0.001) and advanced disease (HR 1.43, 95% CI: 1.07-1.92, p = 0.020) presenting with low levels of muscle mass compared to those presenting with high levels.

DISCUSSION

These results indicate that although overall adiposity should be cautiously interpreted in regards to survival, high muscle mass and SAT, and low VAT/SAT ratio values are associated with overall survival in men with prostate cancer.

Dietary interventions to improve body composition in men treated with androgen deprivation therapy for prostate cancer: a solution for the growing problem?

BACKGROUND

Androgen deprivation therapy (ADT) has adverse effects on body composition, including muscle wasting and body fat accumulation, which may be attenuated by nutrition therapy. This systematic review summarises available evidence on the effects of dietary interventions on lean mass, fat mass and body mass index (BMI) in men treated with ADT for prostate cancer.

METHODS

MEDLINE, Embase, Web of Science and ClinicalTrials.org were searched from inception through December 2020. We included all controlled trials evaluating effects of supplementation or dietary interventions on body composition in men with prostate cancer receiving continuous ADT. Methodological quality of the studies was assessed using the Cochrane Collaboration's risk of bias tool. Meta-analysis was performed using a random effects model to calculate standardised mean differences between intervention and comparator groups. (PROSPERO; CRD42020185777).

RESULTS

Eleven studies (n = 536 participants) were included. Seven studies investigated the effects of dietary advice interventions, e.g. individual or group counselling, and four studies included a nutritional supplement. Eight studies combined the dietary intervention with exercise. Nine studies reported sufficient data for inclusion in the meta-analysis. Dietary advice and supplementation interventions combined were not associated with significant changes in lean mass (0.05 kg; 95% CI: -0.17, 0.26; p = 0.674; n = 355), fat mass (-0.22 kg; 95% CI: -0.45, 0.01; p = 0.064; n = 336) or BMI (-0.16 kg*m-2; 95% CI: -0.37, 0.04; p = 0.121; n = 399). Dietary advice interventions alone were associated with a significant fat mass reduction (-0.29 kg; 95% CI: -0.54, -0.03; p = 0.028; n = 266).

CONCLUSIONS

Most studies were dietary advice interventions targeting caloric restriction, which showed the potential to reduce fat mass but did not increase lean mass in men treated with ADT. Future interventions should investigate whether a combination of dietary advice and protein supplementation with concomitant resistance exercise could counteract ADT-induced muscle wasting.

Exercise in advanced prostate cancer elevates myokine levels and suppresses in-vitro cell growth

BACKGROUND

Altering the systemic milieu through exercise has been proposed as a potential mechanism underlying exercise-driven tumour suppression. It is not yet known whether men with advanced prostate cancer can elicit such adaptations following a program of exercise. The purpose is to examine myokine levels of serum acquired from metastatic castrate-resistant prostate cancer (mCRPC) patients recruited to the INTERVAL-GAP4 trial before and after 6 months of exercise and its tumour-suppressive effect.

METHODS

Twenty-five men with mCRPC (age = 74.7 ± 7.1 yrs) were randomised to supervised multimodal (aerobic and resistance) exercise (EX) or self-directed exercise control group (CON). Body composition was assessed using dual-energy x-ray absorptiometry (DXA), and fasting blood in a rested state was collected at baseline and at 6 months. Serum levels of myokines (SPARC, OSM, decorin, IGF-1, and IGFBP-3) were measured. Serum was applied to the prostate cancer cell line DU145, and growth was assessed for 72 h.

RESULTS

No significant change in body composition was observed. Adjusted serum OSM (P = 0.050) and relative OSM (P = 0.083), serum SPARC (P = 0.022) and relative SPARC (P = 0.025) increased in EX compared to CON. The area under curve (AUC) over 72 h showed a significant reduction in DU145 growth after applying post-intervention serum from the EX vs CON (P = 0.029).

CONCLUSION

Elevated myokine expressions and greater tumour-suppressive effects of serum after 6 months of periodised and autoregulated supervised exercise was observed in men with mCRPC. Exercise-induced systemic changes may slow disease progression in men with advanced prostate cancer.

Potential Role of Exercise Induced Extracellular Vesicles in Prostate Cancer Suppression

Physical exercise is increasingly recognized as a valuable treatment strategy in managing prostate cancer, not only enhancing supportive care but potentially influencing disease outcomes. However, there are limited studies investigating mechanisms of the tumor-suppressive effect of exercise. Recently, extracellular vesicles (EVs) have been recognized as a therapeutic target for cancer as tumor-derived EVs have the potential to promote metastatic capacity by transferring oncogenic proteins, integrins, and microRNAs to other cells and EVs are also involved in developing drug resistance. Skeletal muscle has been identified as an endocrine organ, releasing EVs into the circulation, and levels of EV-containing factors have been shown to increase in response to exercise. Moreover, preclinical studies have demonstrated the tumor-suppressive effect of protein and microRNA contents in skeletal muscle-derived EVs in various cancers, including prostate cancer. Here we review current knowledge of the tumor-derived EVs in prostate cancer progression and metastasis, the role of exercise in skeletal muscle-derived EVs circulating levels and the alteration of their contents, and the potential tumor-suppressive effect of skeletal muscle-derived EV contents in prostate cancer. In addition, we review the proposed mechanism of exercise in the uptake of skeletal muscle-derived EVs in prostate cancer.

Exercise-induced myokines and their effect on prostate cancer

Exercise is recognized by clinicians in the field of clinical oncology for its potential role in reducing the risk of certain cancers and in reducing the risk of disease recurrence and progression; yet, the underlying mechanisms behind this reduction in risk are not fully understood. Studies applying post-exercise blood serum directly to various types of cancer cell lines provide insight that exercise might have a role in inhibiting cancer growth via altered soluble and cell-free blood contents. Myokines, which are cytokines produced by muscle and secreted into the bloodstream, might offer multiple benefits to cellular metabolism (such as a reduction in insulin resistance, improved glucose uptake and reduced adiposity), and blood myokine levels can be altered with exercise. Alterations in the levels of myokines such as IL-6, IL-15, IL-10, irisin, secreted protein acidic risk in cysteine (SPARC), myostatin, oncostatin M and decorin might exert a direct inhibitory effect on cancer growth via inhibiting proliferation, promoting apoptosis, inducing cell-cycle arrest and inhibiting the epithermal transition to mesenchymal cells. The association of insulin resistance, hyperinsulinaemia and hyperlipidaemia with obesity can create a tumour-favourable environment; exercise-induced myokines can manipulate this environment by regulating adipose tissue and adipocytes. Exercise-induced myokines also have a critical role in increasing cytotoxicity and the infiltration of immune cells into the tumour.

CT-based assessment of body composition following neoadjuvant chemohormonal therapy in patients with castration-naïve oligometastatic prostate cancer

BACKGROUND

The purpose of this study is to assess the body composition changes in men with recently diagnosed oligometastatic prostate cancer following neoadjuvant chemohormonal therapy. Further, we evaluated whether CT-based body composition parameters are associated with biochemical recurrence or imaging progression.

MATERIAL AND METHODS

Recently diagnosed castration-naïve oligometastatic prostate cancer patients who received neoadjuvant docetaxel chemotherapy and androgen deprivation treatment (ADT) before prostatectomy and consolidation of local and oligometastatic disease (total eradication therapy), as part of a phase-II prospective clinical trial were included. Body composition parameters including cross-sectional areas of the psoas muscle, total, visceral, and subcutaneous adipose tissue were measured on serial CT scans obtained before and following completion of neoadjuvant treatment.

RESULTS

A total of 22 prostate cancer patients were included (median age 58 years, median Gleason score 8). The median time intervals between commencement of neoadjuvant chemohormonal therapy and first and second follow-up CTs were 3 and 12 months, respectively. Compared to the baseline scan, there were significant declines in psoas muscle cross-sectional areas with estimated percentage declines of -13.9% (IQR: 7.6%-16.5%, p < .001) and -13.2% (IQR: 6%-11.2%, p < .001) on first and second follow-up CTs. There were significant increases in subcutaneous adipose tissue following neoadjuvant chemohormonal therapy with percentage increases of +8.9% (IQR: 5.1%-21.5%, p = .002) and +18.9% (IQR: 6.1%-33.8%, p < .001), respectively. The median follow-up was 34.5 months. The estimated 2-year prostate-specific antigen progression-free and radiologic progression-free survival were 95.5%. No significant association between baseline or percentage change in body composition parameters and disease progression were identified.

CONCLUSIONS

Our findings showed a significant reduction in muscle mass and an increase in subcutaneous adiposity in men treated with neoadjuvant docetaxel and ADT, more pronounced on the first follow-up scan after completion of neoadjuvant treatment. Body composition parameters were not found to be significant predictors of disease progression in our cohort.