Racial/ethnic disparities in weight or BMI change in adulthood and pancreatic cancer incidence: The multiethnic cohort

Genetic and other risk factors for pancreatic ductal adenocarcinoma (PDAC)

Pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at an advanced stage, resulting in poor prognosis and low 5-year survival rates. While early evidence suggests increased long-term survival in those with screen-detected resectable cancers, surveillance imaging is currently only recommended for individuals with a lifetime risk of PDAC ≥ 5%. Identification of risk factors for PDAC provides opportunities for early detection, risk reducing interventions, and targeted therapies, thus potentially improving patient outcomes. Here, we summarize modifiable and non-modifiable risk factors for PDAC. We review hereditary cancer syndromes associated with risk for PDAC and their implications for patients and their relatives. In addition, other biologically relevant pathways and environmental and lifestyle risk factors are discussed. Future work may focus on elucidating additional genetic, environmental, and lifestyle risk factors that may modify PDAC risk to continue to identify individuals at increased risk for PDAC who may benefit from surveillance and risk reducing interventions.

Genetically predicted blood metabolites mediate the association between circulating immune cells and pancreatic cancer: A Mendelian randomization study

BACKGROUND

Pancreatic cancer is characterized by metabolic dysregulation and unique immunological profiles. Nevertheless, the comprehensive understanding of immune and metabolic dysregulation of pancreatic cancer remains unclear. In the present study, we aimed to investigate the causal relationship of circulating immune cells and pancreatic cancer and identify the blood metabolites as potential mediators.

METHODS

The exposure and outcome genome-wide association studies (GWAS) data used in the present study were obtained from the GWAS open-access database (https://gwas.mrcieu.ac.uk). The study used 731 circulating immune cell features, 1400 types of blood metabolites and pancreatic cancer from GWAS. We then performed bidirectional Mendelian randomization (MR) analyses to explore the causal relationships between the circulating immune cells and pancreatic cancer, and two-step MR to discover potential mediating blood metabolites in this process. All statistical analyses were performed in R software. The STROBE-MR (i.e. Strengthening the Reporting of Observational Studies in Epidemiology using Mendelian Randomization) checklist for the reporting of MR studies was also used.

RESULTS

MR analysis identified seven types of circulating immune cells causally associated with pancreatic cancer. Furthermore, there was no strong evidence that genetically predicted pancreatic cancer had an effect on these seven types of circulating immune cells. Further two-step MR analysis found 10 types of blood metabolites were causally associated with pancreatic cancer and the associations between circulating CD39+CD8+ T cells and pancreatic cancer were mediated by blood orotates with proportions of 5.18% (p = 0.016).

CONCLUSIONS

The present study provides evidence supporting the causal relationships between various circulating immune cells, especially CD39+CD8+ T cells, and pancreatic cancer, with a potential effect mediated by blood orotates. Further research is needed on additional risk factors as potential mediators and establish a comprehensive immunity-metabolism network in pancreatic cancer.

Pancreatic cancer: from early detection to personalized treatment approaches

Pancreatic cancer is notorious for its persistently poor prognosis and health outcomes, so some of the questions that may be begged are "Why is it mostly diagnosed at end stage?", "What could we possibly do with the advancing technology in today's world to detect early pancreatic cancer and intervene?", and "Are there any implementation of the existing novel imaging technologies?". Well, to start with, this is in part because the majority of patients presented would already have reached a locally advanced or metastatic stage at the time of diagnosis due to its highly aggressive characteristics and lack of symptoms. Due to this striking disparity in survival, advancements in early detection and intervention are likely to significantly increase patients' survival. Presently, screening is frequently used in high-risk individuals in order to obtain an early pancreatic cancer diagnosis. Having a thorough understanding of the pathogenesis and risk factors of pancreatic cancer may enable us to identify individuals at high risk, diagnose the disease early, and begin treatment promptly. In this review, the authors outline the clinical hurdles to early pancreatic cancer detection, describe high-risk populations, and discuss current screening initiatives for high-risk individuals. The ultimate goal of this current review is to study the roles of both traditional and novel imaging modalities for early pancreatic cancer detection. A lot of the novel imaging techniques mentioned seem promising, but they need to be put to the test on a large scale and may need to be combined with other non-invasive biomarkers before they can be widely used.

Global Burden of Pancreatic Cancer Attributable to High Body-Mass Index in 204 Countries and Territories, 1990-2019

(1) Background: This study aimed to assess the global burden of pancreatic cancer attributable to a high BMI in 1990-2019. (2) Methods: An ecological study was carried out. Data about deaths and Disability-Adjusted Life Years (DALYs) for pancreatic cancer were extracted from the Global Burden of Disease (GBD) study. The age-standardized rates (ASRs, per 100,000) were presented. In order to determine trends of pancreatic cancer burden, joinpoint regression analysis was used to calculate the average annual percent change (AAPC). (3) Results: The highest ASRs of DALYs of pancreatic cancer were found in the United Arab Emirates (47.5 per 100,000), followed by countries with about 25.0 per 100,000 (such as Hungary, Czechia, and Montenegro). From 1990 to 2019, the ASRs of deaths and DALYs of pancreatic cancer attributable to a high BMI significantly increased (p < 0.001) for both sexes in all ages, and across all SDI quintiles and all GBD regions. The highest fraction of DALYs attributable to a high BMI was found in the United States of America and China (equally about 15.0%), followed by the Russian Federation, India, Germany, and Brazil (about 5.0%, equally). (4) Conclusions: Further analytical epidemiological studies are necessary to elucidate the relationship between pancreatic cancer and a high BMI.

Pancreatic Cancer: Changing Epidemiology and New Approaches to Risk Assessment, Early Detection, and Prevention

Pancreatic cancer usually results in poor survival with limited options for treatment, as most affected individuals present with advanced disease. Early detection of preinvasive pancreatic neoplasia and identifying molecular therapeutic targets provide opportunities for extending survival. Although screening for pancreatic cancer is currently not recommended for the general population, emerging evidence indicates that pancreatic surveillance can improve outcomes for individuals in certain high-risk groups. Changes in the epidemiology of pancreatic cancer, experience from pancreatic surveillance, and discovery of novel biomarkers provide a roadmap for new strategies for pancreatic cancer risk assessment, early detection, and prevention.

Effects of physical exercise on body fat and laboratory biomarkers in cancer patients: a meta-analysis of 35 randomized controlled trials

BACKGROUND

A growing number of articles had reported the beneficial effects of physical exercise on reduced risks of cancer recurrence and mortality. However, the associations between physical exercise and laboratory biomarkers still had controversy. As we knew, this meta-analysis of randomized controlled trials (RCTs) was the first time for us to comprehensively clarify their relationships in cancer patients.

METHODS

We comprehensively searched the PubMed, Cochrane Central, EMBASE, Web of Science, and SportDiscus online databases to identify eligible articles, up to June 1, 2021. Pooled standardized mean differences (SMDs) with 95% confidence intervals (CIs) were utilized to clarify their associations. Sensitivity analysis was performed to assess the impact of the individual on overall and Begg's/Egger's plot was utilized to evaluate potential publication bias.

RESULTS

Finally, 35 randomized controlled trials (RCTs) were finally enrolled in this meta-analysis. Our results indicated that physical exercise could significantly reduce BMI (pooled SMD = -0.32 - 0.56 to -0.09)), body weight (pooled SMD = -0.31 (-0.54 to -0.08)), body fat (pooled SMD = -0.44 (-0.70 to -0.18)), waist circumference (pooled SMD = -0.50 (-0.76 to -0.23)), hip circumference (pooled SMD = -0.54 (-0.80 to -0.28)), triglyceride (pooled SMD = -0.35 (-0.69 to -0.02)), fasting insulin (pooled SMD = -0.38 (-0.54 to -0.22)), glucose (pooled SMD = -0.56 (-0.84 to -0.28)), insulin resistance (pooled SMD = -0.40 (-0.72 to -0.07)), CRP (pooled SMD = -0.97 (-1.48 to -0.46)), IGF-1 levels (pooled SMD = -0.56 (-0.83 to -0.29)) and remarkably increase IGFBP-3 levels (pooled SMD = 0.81 (0.45 to 1.17)). Further sensitivity analysis and Begg's or Egger's test suggested that our results were robust with no significant publication bias.

CONCLUSIONS

Our results shed light on the beneficial effects of physical exercise on cancer patients by means of BMI/weight change and various biomarkers alteration (insulin-glucose pathways or inflammatory biomarkers). Our results were anticipated for clinical application to improve cancer patients' prognosis.

Obesity and Pancreatic Cancer: Recent Progress in Epidemiology, Mechanisms and Bariatric Surgery

More than 30% of people in the United States (US) are classified as obese, and over 50% are considered significantly overweight. Importantly, obesity is a risk factor not only for the development of metabolic syndrome but also for many cancers, including pancreatic ductal adenocarcinoma (PDAC). PDAC is the third leading cause of cancer-related death, and 5-year survival of PDAC remains around 9% in the U.S. Obesity is a known risk factor for PDAC. Metabolic control and bariatric surgery, which is an effective treatment for severe obesity and allows massive weight loss, have been shown to reduce the risk of PDAC. It is therefore clear that elucidating the connection between obesity and PDAC is important for the identification of a novel marker and/or intervention point for obesity-related PDAC risk. In this review, we discussed recent progress in obesity-related PDAC in epidemiology, mechanisms, and potential cancer prevention effects of interventions, including bariatric surgery with preclinical and clinical studies.