Exploration of biomarkers from a pilot weight management study for men undergoing radical prostatectomy

Global trends in the management of cancer through obesity reduction: a bibliometric based systematic literature review

Background

The escalating prevalence of obesity poses increased risk for public health, including an increasing incidence of cancer. The association between obesity and cancer has become an area of increasing concern and investigation. Literature on the treatment of obesity leading to a reduction in the incidence of cancer and as an adjunct to cancer-directed therapy is beginning to emerge. We conducted a bibliometric analysis to study the current trends in published literature.

Objectives

The aims of the study were to explore the evolving landscape of obesity-related cancer management and identify the current areas of active research in the field.

Methods

We searched the SCOPUS database on December 11, 2023, to identify the content and patterns of the literature published on the subject of 'treatment of obesity to prevent or treat cancers' using keywords, '(obesity OR overweight OR 'Body Mass Index' OR 'body weight') AND (cancer OR neoplasm) AND (prevention OR 'bariatric surgery' OR 'weight loss' OR 'weight reduction')' in the title, abstract or the author-supplied keywords. After removing non-English and non-journal articles, a manual search was carried out to ensure relevance to the research question. The 'bibliometric package' version R 4.3.2 binaries for macOS 11 (Big Sur) and higher, signed and notarised packages, were used to extract data.

Results

Over the study period, a total of 724 documents were published, 624 were subjected to manual screening and 95 were identified for analysis. An increase in the number of articles was seen from 2017 onward. 'Bradford's law' was applied, and 5 core journals published 33/95 (34.7%) of all articles and received 1,808/4,399 citations (41.1%). The vast majority of articles, reported on the use of bariatric surgery for weight reduction as a method for cancer prevention and as an adjunct to cancer-directed treatment.

Conclusion

The treatment of obesity seems to be emerging as a strategy for the prevention and treatment of cancer. The field is relatively new, publications have begun to emerge in the last 10 years, and there is a growing interest in bariatric surgery as a method to prevent obesity-related cancers.

Intentional weight reduction before surgery - A systematic review

INTRODUCTION

Obesity may increase complexity of surgical procedures and increase the risk of perioperative complications. Weight reduction by the use of low energy diet (LED, ≤1200 kcal/day) or very low energy diet (VLED, ≤800 kcal/day) can reduce postoperative complications after bariatric surgery, but for most other types of surgery the evidence for its use remains uncertain. The aim of this systematic review was therefore to evaluate the scientific evidence in general for this routine.

METHODS

The Medline, Embase, Web of Science and Cochrane databases were searched up until November 20, 2024 using the Cochrane risk of bias assessment tool for observational studies and the NIH quality assessment of controlled intervention studies for randomized trials. Operation time, surgeon's perceived difficulty, intraoperative complications, postoperative complications and relevant efficacy measures for specific procedures were considered as endpoints. A random-effects model was used to pool effect sizes for the main analyses.

RESULTS

A total of 7053 studies were identified. After screening by title and abstract, followed by full text, 18 studies (9 RCTs and 9 observational studies) remained for the analyses including 854 patients who received the intervention and 979 controls. Preoperative LED/VLED resulted in an overall shorter operation time (standard mean difference 0.36, 95 % CI 0.14-0.59, p = 0.002), and reduced risk of postoperative complications after bariatric surgery, cholecystectomy, colorectal surgery and hernia repair (pooled RR 0.63, 95%CI 0.51-0.79, p < 0.001). Heterogeneity between studies was high for operation time but very low for complications. No difference was seen for intraoperative complications, while the data did not allow further analyses on perceived difficulty of surgery or efficacy outcomes.

CONCLUSION

The results support the use of LED/VLED for short-term preoperative weight reduction in patients with obesity planned for bariatric surgery and for those undergoing cholecystectomy, colorectal surgery and hernia repair. Further studies including a comparable control group are needed to evaluate its routine use for other surgical procedures.

REGISTRATION

The protocol of this study was preregistered at the International Prospective Register of Systematic Reviews, PROSPERO.

Impact of Weight Management on Obesity-Driven Biomarkers of Prostate Cancer Progression

PURPOSE

Excess body and visceral fat increase the risk of death from prostate cancer (PCa). This phase II study aimed to test whether weight reduction by > 5% total body weight counteracts obesity-driven PCa biomarkers.

MATERIALS AND METHODS

Forty men scheduled for prostatectomy were randomized into intervention (n = 20) or control (n = 20) arms. Intervention participants followed a weight management program for 4 to 16 weeks before and 6 months after surgery. Control participants received standardized educational materials. All participants attended visits at baseline, 1 week before surgery, and 6 months after surgery. Circulating immune cells, cytokines, and chemokines were evaluated. Weight loss, body composition/distribution, quality of life, and nutrition literacy were assessed. Prostate tissue samples obtained from biopsy and surgery were analyzed.

RESULTS

From baseline to surgery (mean = 5 weeks), the intervention group achieved 5.5% of weight loss (95% CI, 4%-7%). Compared to the control, the intervention also reduced insulin, total cholesterol, LDL cholesterol, leptin, leptin:adiponectin ratio, and visceral adipose tissue. The intervention group had reduced c-peptide, plasminogen-activator-inhibitor-1, and T cell count from baseline to surgery. Myeloid-derived suppressor cells were not statistically different by group. Intervention group anthropometrics improved, including visceral and overall fat loss. No prostate tissue markers changed significantly. Quality of life measures of general and emotional health improved in the intervention group. The intervention group maintained or kept losing to a net loss of 11% initial body weight (95% CI, 8%-14%) at the study end.

CONCLUSIONS

Our study demonstrated improvements in body composition, PCa biomarkers, and quality of life with a weight management intervention.

White adipose tissue-derived factors and prostate cancer progression: mechanisms and targets for interventions

Obesity represents an important risk factor for prostate cancer, driving more aggressive disease, chemoresistance, and increased mortality. White adipose tissue (WAT) overgrowth in obesity is central to the mechanisms that lead to these clinical observations. Adipose stromal cells (ASCs), the progenitors to mature adipocytes and other cell types in WAT, play a vital role in driving PCa aggressiveness. ASCs produce numerous factors, especially chemokines, including the chemokine CXCL12, which is involved in driving EMT and chemoresistance in PCa. A greater understanding of the impact of WAT in obesity-induced progression of PCa and the underlying mechanisms has begun to provide opportunities for developing interventional strategies for preventing or offsetting these critical events. These include weight loss regimens, therapeutic targeting of ASCs, use of calorie restriction mimetic compounds, and combinations of compounds as well as specific receptor targeting strategies.