Obesity and cancer risk: Emerging biological mechanisms and perspectives

The association between triglycerides and ectopic fat obesity: An inverted U-shaped curve

Background

Ectopic fat obesity and triglycerides are risk factors for diabetes and multiple cardiovascular diseases. However, there have been limited studies on the association between triglycerides and ectopic fat obesity. The purpose of this study was to explore the association between triglycerides and ectopic fat obesity.

Methods and results

In this cross-sectional study, we retrospectively analyzed 15464 adult participants recruited by Murakami Memorial Hospital (8430 men and 7034 women, average age of 43.71 ± 8.90). All patients were divided into two groups according to the threshold used to diagnose hypertriglyceridemia. The logistic regression model was used to analyze the association between triglycerides and the risk of ectopic fat obesity, and the generalized additive model was used to identify the nonlinear association. In this study population, the prevalence of ectopic fat obesity was 17.73%. After adjusting other covariables, triglycerides were positively correlated with the risk of ectopic fat obesity (OR: 1.54, 95% CI:1.41–1.69, P<0.0001). Through smooth curve fitting, we found that there was an inverted U-shaped curve association between triglycerides and ectopic fat obesity. This association remained unchanged even if the adjusted covariables were removed from the model, and the inflection point of the curve was 3.98. When triglyceride levels were ≤3.98, triglycerides were positively correlated with the risk of ectopic fat obesity (OR:1.784, 95% CI:1.611–1.975, P<0.0001). When triglyceride levels were >3.98 (right side of the inflection point), there was a negative correlation (OR:0.519, 95% CI:0.333–0.810, P = 0.0039).

Conclusions

Our research showed that there is a significant association between triglycerides and ectopic fat obesity. This relation is not a simple linear relationship but instead an inverted U-shaped curve association.

High-Fat Diet and Feeding Regime Impairs Number, Phenotype, and Cytotoxicity of Natural Killer Cells in C57BL/6 Mice

Overweight and obesity are major public health challenges worldwide. Obesity is associated with a higher risk for the development of several cancer types, but specific mechanisms underlying the link of obesity and cancer are still unclear. Natural killer (NK) cells are circulating lymphoid cells promoting the elimination of virus-infected and tumor cells. Previous investigations demonstrated conflicting results concerning the influence of obesity on functional NK cell parameters in small animal models. The aim of the present study was to clarify potential obesity-associated alterations of murine NK cells in vivo, implementing different feeding regimes. Therefore, C57BL/6 mice were fed a normal-fat diet (NFD) or high-fat diet (HFD) under restrictive and ad libitum feeding regimes. Results showed diet and feeding-regime dependent differences in body weight, visceral fat mass and plasma cytokine concentrations. Flow cytometry analyses demonstrated significant changes in total cell counts as well as frequencies of immune cell populations in peripheral blood comparing mice fed NFD or HFD in an ad libitum or restrictive manner. Mice fed the HFD showed significantly decreased frequencies of total NK cells and the mature CD11b⁺CD27⁺ NK cell subset compared to mice fed the NFD. Feeding HFD resulted in significant changes in the expression of the maturation markers KLRG1 and CD127 in NK cells. Furthermore, real-time PCR analyses of NK-cell related functional parameters in adipose tissue revealed significant diet and feeding-regime dependent differences. Most notable, real-time cytotoxicity assays demonstrated an impaired cytolytic activity of splenic NK cells toward murine colon cancer cells in HFD-fed mice compared to NFD-fed mice. In conclusion, our data demonstrate that feeding a high-fat diet influences the frequency, phenotype and function of NK cells in C57BL/6 mice. Interestingly, restricted feeding of HFD compared to ad libitum feeding resulted in a partial prevention of the obesity-associated alterations on immune cells and especially on NK cells, nicely fitting with the current concept of an advantage for interval fasting for improved health.

Obesity-related protein biomarkers for predicting breast cancer risk: an overview of systematic reviews

BACKGROUND

Based on the biological mechanisms underlying the obesity-breast cancer connections, potential protein biomarkers involved in breast cancer development have been identified, which may be helpful for the estimation of breast cancer risk. This study aimed to carry out a comprehensive overview of systematic reviews on circulating levels of obesity-related protein biomarkers for female breast cancer risk to provide a solid reference for potential breast cancer predictors.

METHODS

Comprehensive literature searches were conducted in MEDLINE, EMBASE and Cochrane Database of Systematic Reviews up to Dec 2019. The AMSTAR tool was used for the methodological quality assessment of the included systematic reviews. Evidence was reported narratively.

RESULTS

A total of 28 relevant systematic reviews which were mostly of moderate quality were included in the overview. Protein biomarkers relating to adipokines, insulin/insulin-like growth factor-1 (IGF-1) axis, inflammatory cytokines and sex hormones were investigated. Higher levels of circulating IGF-1, IGF-binding protein-3, leptin and resistin were found to be associated with an increased risk of premenopausal breast cancer; lower levels of circulating adiponectin and higher levels of circulating c-reactive protein, leptin, and resistin were found to be associated with an increased risk of postmenopausal breast cancer.

CONCLUSIONS

We found sufficient evidence on the positive associations between certain obesity-related protein biomarkers with pre- and/or postmenopausal breast cancer risk. These biomarkers could be used jointly as predictors, so as to build a comprehensive risk predictive score for female breast cancer.

PROSPERO REGISTRATION NUMBER

CRD42020175328.

Lipid Regulatory Proteins as Potential Therapeutic Targets for Ovarian Cancer in Obese Women

Obesity has become a recognized global epidemic that is associated with numerous comorbidities including type II diabetes, cardiovascular disease, hypertension, and cancer incidence and progression. Ovarian cancer (OvCa) has a unique mechanism of intra-peritoneal metastasis, already present in 80% of women at the time of diagnosis, making it the fifth leading cause of death from gynecological malignancy. Meta-analyses showed that obesity increases the risk of OvCa progression, leads to enhanced overall and organ-specific tumor burden, and adversely effects survival of women with OvCa. Recent data discovered that tumors grown in mice fed on a western diet (40% fat) have elevated lipid levels and a highly increased expression level of sterol regulatory element binding protein 1 (SREBP1). SREBP1 is a master transcription factor that regulates de novo lipogenesis and lipid homeostasis, and induces lipogenic reprogramming of tumor cells. Elevated SREBP1 levels are linked to cancer cell proliferation and metastasis. This review will summarize recent findings to provide a current understanding of lipid regulatory proteins in the ovarian tumor microenvironment with emphasis on SREBP1 expression in the obese host, the role of SREBP1 in cancer progression and metastasis, and potential therapeutic targeting of SREBPs and SREBP-pathway genes in treating cancers, particularly in the context of host obesity.

Sugar-containing beverages and their association with risk of breast, endometrial, ovarian and colorectal cancers among Canadian women

BACKGROUND

The association of sugar containing beverages (SCBs) with risk of breast, endometrial, ovarian and colorectal cancers is unclear. Therefore, we investigated these associations in the Canadian Study of Diet, Lifestyle, and Health.

METHODS

The study population comprised an age-stratified subcohort of 3185 women and 848, 161, 91 and 243 breast, endometrial, ovarian and colorectal cancer cases, respectively. We used Cox proportional hazards regression models modified for the case-cohort design to assess the associations of SCBs with risk of the aforementioned cancers.

RESULTS

Compared to SCB intake in the lowest tertile, SCB intake in the highest tertile was positively associated with endometrial cancer risk (HR_{T3 vs T1} = 1.58, 95 % CI = 1.08-2.33 and 1.78, 95 % CI = 1.12-2.81 for overall and Type 1 endometrial cancer, respectively) and ovarian cancer (HR_{T3 vs T1} = 1.76, 95 % CI: 1.09-2.83). Fruit juice intake was also positively associated with risk of Type 1endometrial (HR_{T3 vs T1} = 1.63, 95 % CI = 1.03-2.60). After excluding women with diabetes or cardiovascular diseases, we also observed sugar-sweetened beverages (SSBs) intake in the highest tertile was associated with higher risk of Type 1 endometrial cancer (HR _{T3 vs T1} = 1.65; 95 % CI: 1.03-2.64). None of the beverages was associated with risk of breast or colorectal cancer.

CONCLUSION

We conclude that, in this cohort, relatively high SCB intake was associated with higher risk of endometrial and ovarian cancers, but not of breast or colorectal cancers. Our findings also suggest that relatively high SSB and fruit juice intake are associated with higher risk of Type 1 endometrial cancer.

Adipokines, Myokines, and Cardiokines: The Role of Nutritional Interventions

It is now established that adipose tissue, skeletal muscle, and heart are endocrine organs and secrete in normal and in pathological conditions several molecules, called, respectively, adipokines, myokines, and cardiokines. These secretory proteins constitute a closed network that plays a crucial role in obesity and above all in cardiac diseases associated with obesity. In particular, the interaction between adipokines, myokines, and cardiokines is mainly involved in inflammatory and oxidative damage characterized obesity condition. Identifying new therapeutic agents or treatment having a positive action on the expression of these molecules could have a key positive effect on the management of obesity and its cardiac complications. Results from recent studies indicate that several nutritional interventions, including nutraceutical supplements, could represent new therapeutic agents on the adipo-myo-cardiokines network. This review focuses the biological action on the main adipokines, myokines and cardiokines involved in obesity and cardiovascular diseases and describe the principal nutraceutical approaches able to regulate leptin, adiponectin, apelin, irisin, natriuretic peptides, and follistatin-like 1 expression.

Roles of Adipokines in Digestive Diseases: Markers of Inflammation, Metabolic Alteration and Disease Progression

Adipose tissue is a highly dynamic endocrine tissue and constitutes a central node in the interorgan crosstalk network through adipokines, which cause pleiotropic effects, including the modulation of angiogenesis, metabolism, and inflammation. Specifically, digestive cancers grow anatomically near adipose tissue. During their interaction with cancer cells, adipocytes are reprogrammed into cancer-associated adipocytes and secrete adipokines to affect tumor cells. Moreover, the liver is the central metabolic hub. Adipose tissue and the liver cooperatively regulate whole-body energy homeostasis via adipokines. Obesity, the excessive accumulation of adipose tissue due to hyperplasia and hypertrophy, is currently considered a global epidemic and is related to low-grade systemic inflammation characterized by altered adipokine regulation. Obesity-related digestive diseases, including gastroesophageal reflux disease, Barrett's esophagus, esophageal cancer, colon polyps and cancer, non-alcoholic fatty liver disease, viral hepatitis-related diseases, cholelithiasis, gallbladder cancer, cholangiocarcinoma, pancreatic cancer, and diabetes, might cause specific alterations in adipokine profiles. These patterns and associated bases potentially contribute to the identification of prognostic biomarkers and therapeutic approaches for the associated digestive diseases. This review highlights important findings about altered adipokine profiles relevant to digestive diseases, including hepatic, pancreatic, gastrointestinal, and biliary tract diseases, with a perspective on clinical implications and mechanistic explorations.

Immune Checkpoints and CAR-T Cells: The Pioneers in Future Cancer Therapies?

Although the ever-increasing number of cancer patients pose substantial challenges worldwide, finding a treatment with the highest response rate and the lowest number of side effects is still undergoing research. Compared to chemotherapy, the relatively low side effects of cancer immunotherapy have provided ample opportunity for immunotherapy to become a promising approach for patients with malignancy. However, the clinical translation of immune-based therapies requires robust anti-tumoral immune responses. Immune checkpoints have substantial roles in the induction of an immunosuppressive tumor microenvironment and tolerance against tumor antigens. Identifying and targeting these inhibitory axes, which can be established between tumor cells and tumor-infiltrating lymphocytes, can facilitate the development of anti-tumoral immune responses. Bispecific T-cell engagers, which can attract lymphocytes to the tumor microenvironment, have also paved the road for immunological-based tumor elimination. The development of CAR-T cells and their gene editing have brought ample opportunity to recognize tumor antigens, independent from immune checkpoints and the major histocompatibility complex (MHC). Indeed, there have been remarkable advances in developing various CAR-T cells to target tumoral cells. Knockout of immune checkpoints via gene editing in CAR-T cells might be designated for a breakthrough for patients with malignancy. In the midst of this fast progress in cancer immunotherapies, there is a need to provide up-to-date information regarding immune checkpoints, bispecific T-cell engagers, and CAR-T cells. Therefore, this review aims to provide recent findings of immune checkpoints, bispecific T-cell engagers, and CAR-T cells in cancer immunotherapy and discuss the pertained clinical trials.

Terpenes with Antitumor Activity: A Patent Review

BACKGROUND

Cancer is a major public health concern, and is one of the leading causes of death globally. Surgical removal, chemotherapy or hormonal therapy, radiation therapy, or a combination of them are treatment for cancer, many of which are ineffective or have serious side effects. In view of this, there is a search for new, more effective alternatives for cancer prevention and treatment. One possible source of compounds are natural products; among them, terpenes, a large class of organic compounds, have shown promise due to their anti-inflammatory, anti-tumorigenic, and hypolipidemic properties, among others recorded in the literature.

OBJECTIVE

The study aims to use a patent review to evaluate the development and use of terpenes, or formulations containing terpenes, in new therapeutic options for the treatment of various types of cancer.

METHODS

This patent review was carried out using the specialized patent databases of WIPO and Espacenet. The selection of patents was based on the following inclusion criteria which included pre-clinical and/or clinical trials, and demonstrated anti-tumor effects.

RESULTS

Eight patents were identified, six from China, and two from Japan. In this review, all patents confirmed having good antitumor activity for many types of cancer cells. In addition, the inventors indicate more studies pre-clinical and clinical trials giving greater clarity and accurate reflection of the activity of the products studied.

CONCLUSION

Natural products are an important source of compounds for use in the fight against cancer that can act synergistically, and help in the treatment of cancer.

Evaluation of Diet Quality Among American Adult Cancer Survivors: Results From 2005-2016 National Health and Nutrition Examination Survey

BACKGROUND

Diet quality among adult cancer survivors is low, and there is minimal information on the Healthy Eating Index (HEI)-2015 score, a measure of diet quality and adherence to the 2015-2020 Dietary Guidelines for Americans, in this population.

OBJECTIVE

This study aimed to examine HEI-2015 total and component scores and associated factors among adult cancer survivors. Also, this study examined which dietary components needed the most change to improve diet quality in this population.

DESIGN

The National Health and Nutrition Examination Survey (NHANES) is an ongoing nationally representative population-based cross-sectional study that is conducted annually.

PARTICIPANTS/SETTING

In all, 1971 adults with a self-reported cancer diagnosis in their lifetime (both individuals with cancer currently and those that are cancer-free) from NHANES 2005-2016 were included in this study.

MAIN OUTCOME MEASURES

HEI-2015 total and 13 component scores were calculated using the simple scoring algorithm method from the average of 2 24-hour recalls.

STATISTICAL ANALYSES

The associations of the HEI-2015 total score with sociodemographic, lifestyle, and health-related factors were analyzed using the least square means comparisons. A multivariable survey regression model was used to identify associations with the HEI-2015 total score after adjustment for potential confounders. The 13 component scores were also compared by participant characteristics to identify target food groups for subgroup-specific nutrition intervention.

RESULTS

The average HEI-2015 total score was 55.6 (95% confidence interval = 54.8-56.4). Factors associated with the HEI-2015 total score included age, race/ethnicity, education, smoking status, body mass index, and oral health status. Overall, poor adherence to the 2015-2020 Dietary Guidelines for Americans was found for most HEI-2015 components, with Whole Grains, Greens and Beans, Sodium, and Fatty Acids components having less than 50% of the maximum possible scores.

CONCLUSIONS

Results indicate poor diet quality among American adult cancer survivors, with significant disparities observed across sociodemographic and lifestyle factors, particularly education levels, body mass index, and smoking status. Nutrition interventions for cancer survivors should consider focusing on improving diet quality by increasing intakes of whole grains and greens and beans, lowering sodium consumption, and achieving a healthy balance of fatty acids (ie, a favorable ratio of unsaturated fats to saturated fats).

D. Custódio I, Silva ATF, C. C. Ferreira I, C. Marinho E, C. Caixeta D, V. Souza A, R. Teixeira R, Araújo TG, Shivappa N, R. Hébert J, Paiva CE, S. Espíndola F, Goulart LR, C. P. Maia Y. Overweight Women with Breast Cancer on Chemotherapy Have More Unfavorable Inflammatory and Oxidative Stress Profiles

Chronic inflammation and redox imbalance are strongly influenced by diet and nutritional status, and both are risk factors for tumor development. This prospective study aimed to explore the associations between inflammatory and antioxidant markers and nutritional status in women with breast cancer undergoing chemotherapy. The women were evaluated at three times: T0, after the infusion of the first cycle; T1, after infusion of the intermediate cycle; and T2, after the infusion of the last chemotherapy cycle. The consumption of antioxidant nutrients and the Total Dietary Antioxidant Capacity reduced between T0 and T2 and the Dietary Inflammatory Index scores increased throughout the chemotherapy. Blood samples taken at the end of the chemotherapy showed lower levels of glutathione reductase and reduced glutathione, with greater quantification of the transcripts for Interleukin-6 and Tumor Necrosis Factor α. It should be emphasized that the Total Dietary Antioxidant Capacity is lower and the Dietary Inflammatory Index is higher in the group of overweight patients at the end of the follow-up, besides showing lower levels of the redox status, especially the plasma levels of glutathione reductase (p = 0.039). In addition, trends towards higher transcriptional levels of cytokines in peripheral blood were observed more often in overweight women than in non-overweight women. In this study of 55 women with breast cancer, nine (16%) with metastases, diet became more pro-inflammatory with fewer antioxidants during the chemotherapy. Briefly, we have shown that chemotherapy is critical for high-risk overweight women due to their reduced intake of antioxidant nutrients, generating greater inflammatory and oxidative stress profiles, suggesting the adoption of healthier dietary practices by women with breast cancer throughout their chemotherapy.

An in silico approach to identify and prioritize miRNAs target sites polymorphisms in colorectal cancer and obesity

Colorectal cancer (CRC) and obesity are linked clinical entities with a series of complex processes being engaged in their development. MicroRNAs (miRNAs) participate in these processes through regulating CRC and obesity‐related genes. This study aimed to develop an in silico approach to systematically identify and prioritize miRNAs target sites polymorphisms in obesity and CRC. Data from genome‐wide association studies (GWASs) were used to retrieve CRC and obesity‐associated variants. The polymorphisms that were resided in experimentally verified or computationally predicted miRNA target sites were retrieved and prioritized using a range of bioinformatics analyses. We found 6284 CRC and 38931 obesity unique variants. For CRC 33 haplotypes variants in 134 interactions were in miRNA targetome, while for obesity we found more than 935 unique interactions. Functionally prioritized SNPs revealed that, SNPs in 153 obesity and 50 CRC unique interactions were have disruptive effects on miRNA:mRNA integration by changing on target RNA secondary structure. Structural accessibility of target sites were decreased in 418 and 103 unique interactions and increased in 516 and 79 interactions, for obesity and CRC, respectively. The miRNA:mRNA hybrid stability was increased in 127 and 17 unique interactions and decreased in 33 and 24 interactions for the effect of obesity and CRC SNPs, respectively. In this study, seven SNPs with 15 interactions and three SNPs with four interactions were prioritized for obesity and CRC, respectively. These SNPs could be used for future studies for finding potential biomarkers for diagnoses, prognosis, or treatment of CRC and obesity.

Causal associations between urinary sodium with body mass, shape and composition: a Mendelian randomization study

Observational studies have found associations between urinary sodium (UNa) with obesity, body shape and composition; but the findings may be biased by residual confounding. The objective of this two-sample Mendelian randomization (MR) study was to analyze their causal associations in both sex-combined and sex-specific models. Genome-wide association studies of UNa, body mass index (BMI), BMI-adjusted waist-to-hip ratio (WHR), body fat (BF) percentage and estimated glomerular filtration rate (eGFR) were identified. We initially extracted fifty SNPs associated with UNa at significance level of 5 × 10^–8, but further removed those SNPs with potential horizontal pleiotropy. Univariable and multivariable MR with adjustment for eGFR were performed. Inverse-variance weighted MR was performed as the primary analysis, with MR-Egger methods as sensitivity analysis. The potential bidirectional association between BMI and UNa was investigated. All exposure and outcomes were continuous, and the effect measure was regression coefficients (beta) and their 95% confidence intervals (95% CI). The total sample size was up to 322 154. UNa was causally associated with increased BMI in both men [eGFR-adjusted beta 0.443 (0.163–0.724)] and women [0.594 (0.333–0.855)]. UNa caused BF percentage increase in men [0.622 (0.268–0.976)] and women [0.334 (0.007–0.662)]. UNa significantly elevated BMI-adjusted WHR in men [0.321 (0.094–0.548)], but not in women [0.170 (− 0.052 to 0.391)]. Additionally, we found that BMI causally increased UNa [0.043 (0.023–0.063)]. UNa increased BMI and BF percentage. Salt intake affects male body shape by increasing BMI-adjusted WHR, but showed no effects on female body shape. The bidirectional association between BMI and UNa suggested that salt reduction measures and weight reduction measures should be implemented simultaneously to break the vicious cycle and gain more health benefits.

Dietary and lifestyle factors effect erythrocyte PIG-A mutant frequency in humans

It is well understood that poor diet and lifestyle choices can increase the risk of cancer. It is also well documented that cancer is a disease of DNA mutations, with mutations in key genes driving carcinogenesis. Measuring these mutations in a minimally invasive way may be informative as to which exposures are harmful and thus allow us to introduce primary preventative measures, in a bid to reduce cancer incidences. Here, we have measured mutations in the phosphatidylinositol glycan class A (PIG-A) gene in erythrocytes from healthy volunteers (n = 156) and from non-cancer patients attending the local endoscopy department (n = 144). The X-linked PIG-A gene encodes an enzyme involved in glycosylphosphatidylinositol (GPI) anchor synthesis. A silencing mutation in which leads to the absence of GPI anchors on the extracellular surface which can be rapidly assessed using flow cytometry. The background level of PIG-A mutant erythrocytes was 2.95 (95% CI: 2.59-3.67) mutant cells (10-6). Older age increased mutant cell frequency (P < 0.001). There was no difference in mutant cell levels between males and females (P = 0.463) or smokers and non-smokers (P = 0.186). In the endoscopy group, aspirin users had lower mutant frequencies (P = 0.001). Further information on diet and exercise was available for the endoscopy patient group alone, where those with a higher health promotion index score had lower mutant frequencies (P = 0.011). Higher dietary intake of vegetables reduced mutant cell levels (P = 0.022). Participants who exercised for at least 1 h a week appeared to have reduced mutant frequencies than those who did not exercise, although this was not statistically significant (P = 0.099). This low background level of mutant erythrocytes in a population makes this assay an attractive tool to monitor exposures such as those associated with lifestyles and diet, as demonstrated here.

Colorectal Cancer Genetics, Incidence and Risk Factors: In Search for Targeted Therapies

Each year, colorectal cancers (CRCs) affect over a quarter of a million people. The risk of developing CRC in industrialized nations is approximately 5%. When the disease is localised, treatment success rates range from 70-90%; however, advanced CRC has a high mortality rate, consistently ranking in the top three causes of cancer-related deaths. There is a large geographic difference in global distribution, and CRC is predominantly associated with developed countries and a Western lifestyle and diet. As such, the developed world accounts for more than 63% of all cases of CRC. Geographic variations also predict cancer outcomes, which differ between racial and ethnic groups. This variation is due to inequalities in wealth, differences in the exposure to risk factors and barriers to high-quality cancer prevention, early detection and treatment. The aim of this paper was to review CRC in low- and middle-income countries such as South Africa, India, Brazil and China, and compare them with high-income countries such as the United States of America and the United Kingdom. It is important to note that these economically less developed countries, with historically low CRC rates, are experiencing an increased frequency of CRC. The review also discusses biological markers and genetic pathways involved in the development of colorectal cancer. Genes known to be responsible for the most common forms of inherited CRCs have also been identified but more remain to be identified. This would provide more candidate genes to be added to known biomarkers. CRC burden can be controlled through the widespread application of existing knowledge, such as reduced smoking habits, vaccination, early detection and promoting physical activity, accompanied by a healthy diet. An increased understanding of the molecular mechanisms and events underlying colorectal carcinogenesis will enable the development of new targets and therapeutic drugs.

Prospective Cohort Study of Pre- and Postdiagnosis Physical Activity and Endometrial Cancer Survival

PURPOSE

The aim of this study was to evaluate associations between pre- and postdiagnosis physical activity and survival in survivors of endometrial cancer by physical activity domain, intensity, dose (metabolic-equivalent task [MET]-hours/week/year), and change from pre- to postdiagnosis.

METHODS

We conducted a prospective cohort study in Alberta, Canada, of 425 women who were diagnosed with histologically confirmed invasive endometrial cancer between 2002 and 2006 and observed to 2019. The interviewer-administered Lifetime Total Physical Activity Questionnaire recorded prediagnosis (assessed at a median of 4.4 months after diagnosis) and postdiagnosis physical activity (assessed at a median of 3.4 years after diagnosis). Associations between physical activity and overall and disease-free survival were assessed using Cox proportional hazards models adjusted for age, stage, grade, treatments, body mass index, menopausal status, hormone therapy use, family history of cancer, and comorbidities.

RESULTS

After a median follow-up of 14.5 years, there were 60 deaths, including 18 endometrial cancer deaths, and 80 disease-free survival events. Higher prediagnosis recreational physical activity was statistically significantly associated with improved disease-free survival (> 14 v ≤ 8 MET-hours/week/year; hazard ratio [HR], 0.54; 95% CI, 0.30 to 0.96; P_trend = .04), but not overall survival (HR, 0.56; 95% CI, 0.29 to 1.07; P_trend = .06). Higher postdiagnosis recreational physical activity (> 13 v ≤ 5 MET-hours/week/year) was strongly associated with both improved disease-free survival (HR, 0.33; 95% CI, 0.17 to 0.64; P_trend = .001) and overall survival (HR, 0.33; 95% CI, 0.15 to 0.75; P_trend = .007). Participants who maintained high recreational physical activity levels from pre- to postdiagnosis also had improved disease-free survival (HR, 0.35; 95% CI, 0.18 to 0.69) and overall survival (HR, 0.43; 95% CI, 0.20 to 0.94) compared with those who maintained low physical activity levels.

CONCLUSION

Recreational physical activity, especially postdiagnosis, is associated with improved survival in survivors of endometrial cancer.

Therapeutic Time-restricted Feeding Reduces Renal Tumor Bioluminescence in Mice but Fails to Improve Anti-CTLA-4 Efficacy

BACKGROUND/AIM

Dietary interventions like time-restricted feeding (TRF) show promising anti-cancer properties. We examined whether therapeutic TRF alone or combined with immunotherapy would diminish renal tumor growth in mice of varying body weights.

MATERIALS AND METHODS

Young (7 week) chow-fed or older (27 week) high-fat diet (HFD)-fed BALB/c mice were orthotopically injected with renal tumor cells expressing luciferase. After tumor establishment, mice were randomized to ad libitum feeding or TRF +/- anti-CTLA-4. Body composition, tumor viability and growth, and immune responses were quantified.

RESULTS

TRF alone reduced renal tumor bioluminescence in older HFD-fed, but not young chow-fed mice. In the latter, TRF mitigated tumor-induced loss of lean- and fat-mass. However, TRF did not alter excised renal tumor weights or intratumoral immune responses and failed to improve anti-CTLA-4 outcomes in any mice.

CONCLUSION

Therapeutic TRF exhibits modest anti-cancer properties but fails to improve anti-CTLA-4 immune checkpoint blockade in murine renal cancer.

Obesity as a risk factor for thyroid cancer

PURPOSE OF REVIEW

In this review, we evaluate recent findings related to the association between obesity and thyroid cancer.

RECENT FINDINGS

During the last several decades, the prevalence of obesity and thyroid cancer have been increasing in parallel on a global scale. Current evidence suggests that the growing incidence of differentiated thyroid cancer (DTC) is pathogenically linked to the spread of obesity, but the biological mechanisms that may explain this connection have been only partially described. Furthermore, unlike other tumors, data on the impacts of obesity on the aggressiveness of DTC and response to treatment of DTC remain conflicting.

SUMMARY

Emergent knowledge regarding the links between obesity and thyroid cancer suggests a relevant role for obesity as a risk factor for DTC, with no apparent impact on its aggressiveness.

Botryosphaeran, a (1 → 3)(1 → 6)-β-D-glucan, reduces tumor development and cachexia syndrome in obese male rats by increasing insulin sensitivity and FOXO3a activity

Obesity is an important risk factor in tumor development. Botryosphaeran, a (1 → 3)(1 → 6)-β-D-glucan, produced by the fungus Botryosphaeria rhodina (MAMB-05), is a high molecular mass, water-soluble exopolysaccharide. It consists of a main chain of (1 → 3)-linked β-d-glucose units, with a degree of branching of ~22% at carbon-6 with glucose and gentiobiose residues linked through β-(1 → 6)-bonds, and presents a triple helix conformation. Botryosphaeran presents anticlastogenic, antiproliferative, pro-apoptotic and anti-obesogenic activities. This study evaluated the effects of botryosphaeran on tumor development in obesity and analyzed its mechanism of action. Obesity was induced in male Wistar rats by a high-fat/high-sugar diet. After 9 weeks, rats were divided into two groups: Obese Tumor (OT) and Obese Tumor Botryosphaeran (OTB), and inoculated with 1 × 10⁷ Walker-256 tumor cells, and treatment with botryosphaeran (30 mg/kg b.w./day via gavage for 15 days) commenced. On the 11th week, biological parameters, tumor development, metabolic profile, erythrogram and protein expression were evaluated. Botryosphaeran significantly reduced tumor growth, body-weight loss and cachexia. Furthermore, botryosphaeran decreased mesenteric fat and insulin resistance, corrected macrocytic anemia, and increased Forkhead transcription factor-3a (FOXO3a) activity. Our study demonstrated the potential role of botryosphaeran in the management of cancer in tumor-bearing obese rats by increasing insulin sensitivity and FOXO3a activity.

Adherence to Cancer Prevention Guidelines and Endometrial Cancer Risk: Evidence from a Systematic Review and Dose-Response Meta-analysis of Prospective Studies

Purpose

The evidence of adherence to cancer prevention guidelines and endometrial cancer (EC) risk has been limited and controversial. This study summarizes and quantifies the relationship between adherence to cancer prevention guidelines and EC risk.

Materials and Methods

The online databases PubMed, Web of Science, and EMBASE were searched for relevant publications up to June 2, 2020. This study had been registered at PROSPERO. The registration number is CRD42020149966. Study quality evaluation was performed based on the Newcastle-Ottawa Scale. The I² statistic was used to estimate heterogeneity among studies. Egger’s and Begg’s tests assessed potential publication bias. Summary hazard ratios (HRs) and 95% confidence intervals (CIs) for the relationship between adherence to cancer prevention guidelines score was assigned to participants by summarizing individual scores for each lifestyle-related factor. The scores ranged from least healthy (0) to most healthy (20) and the EC risk was calculated using a random-effects model.

Results

Five prospective studies (four cohort studies and one case-cohort study) consisted of 4,470 EC cases, where 597,047 participants were included. Four studies had a low bias risk and one study had a high bias risk. Summary EC HR for the highest vs. lowest score of adherence to cancer prevention guidelines was 0.54 (95% CI, 0.40 to 0.73) and had a high heterogeneity (I²=86.1%). For the dose-response analysis, an increment of 1 significantly reduced the risk of EC by 6%. No significant publication bias was detected.

Conclusion

This study suggested that adherence to cancer prevention guidelines was negatively related to EC risk.

Diet and gut microbiome interactions in gynecologic cancer

Over the last decade, there has been a dramatic surge in research exploring the human gut microbiome and its role in health and disease. It is now widely accepted that commensal microorganisms coexist within the human gastrointestinal tract and other organs, including those of the reproductive tract. These microorganisms, which are collectively known as the "microbiome", contribute to maintaining host physiology and to the development of pathology. Next generation sequencing and multi-'omics' technology has enriched our understanding of the complex and interdependent relationship that exists between the host and microbiome. Global changes in the microbiome are known to be influenced by dietary, genetic, lifestyle, and environmental factors. Accumulating data have shown that alterations in the gut microbiome contribute to the development, prognosis and treatment of many disease states including cancer primarily through interactions with the immune system. However, there are large gaps in knowledge regarding the association between the gut microbiome and gynecologic cancers, and research characterizing the reproductive tract microbiome is insufficient. Herein, we explore the mechanisms by which alterations in the gut and reproductive tract microbiome contribute to carcinogenesis focusing on obesity, hyperestrogenism, inflammation and altered tumor metabolism. The impact of the gut microbiome on response to anti-cancer therapy is highlighted with an emphasis on immune checkpoint inhibitor efficacy in gynecologic cancers. We discuss dietary interventions that are likely to modulate the metabolic and immunologic milieu as well as tumor microenvironment through the gut microbiome including intermittent fasting/ketogenic diet, high fiber diet, use of probiotics and the metabolic management of obesity. We conclude that enhanced understanding of the microbiome in gynecologic cancers coupled with thorough evaluation of metabolic and metagenomic analyses would enable us to integrate novel preventative strategies and adjunctive interventions into the care of women with gynecologic cancers.

Correlation between obesity and clinicopathological characteristics in patients with papillary thyroid cancer: a study of 1579 cases: a retrospective study

Objective

To explore the relationship between body mass index (BMI) and clinicopathological characteristics in patients with papillary thyroid carcinoma (PTC).

Methods

The clinical data of 1,579 patients with PTC, admitted to our hospital from May 2016 to March 2017, were retrospectively analyzed. According to the different BMI of patients, it can be divided into underweight recombination (BMI < 18.5 kg/m), normal body recombination (18.5 ≤ BMI < 24.0 kg/m²), overweight recombination (24.0 ≤ BMI < 28.0 kg/m²) and obesity group (BMI ≥ 28.0 kg/m²). The clinicopathological characteristics of PTC in patients with different BMIs group were compared.

Results

In our study, the risk for extrathyroidal extension (ETE), advanced T stage (T III/IV), and advanced tumor-node-metastasis stage (TNM III/IV) in the overweight group were higher, with OR (odds ratio) = 1.99(1.41-2.81), OR = 2.01(1.43-2.84), OR = 2.94(1.42-6.07), respectively, relative to the normal weight group. The risk for ETE and T III/IV stage in the obese group were higher, with OR = 1.82(1.23-2.71) and OR = 1.82(1.23-2.70), respectively, relative to the normal weight group.

Conclusion

BMI is associated with the invasiveness of PTC. There is a higher risk for ETE and TNM III/IV stage among patients with PTC in the overweight group and for ETE among patients with PTC in the obese group.

Gender medicine: Lessons from COVID-19 and other medical conditions for designing health policy

Gender-specific differences in the prevalence, incidence, comorbidities, prognosis, severity, risk factors, drug-related aspects and outcomes of various medical conditions are well documented. We present a literature review on the extent to which research in this field has developed over the years, and reveal gaps in gender-sensitive awareness between the clinical portrayal and the translation into gender-specific treatment regimens, guidelines and into gender-oriented preventive strategies and health policies. Subsequently, through the lens of gender, we describe these domains in detail for four selected medical conditions: Asthma, obesity and overweight, chronic kidney disease and coronavirus disease 2019. As some of the key gender differences become more apparent during adolescence, we focus on this developmental stage. Finally, we propose a model which is based on three influential issues: (1) Investigating gender-specific medical profiles of related health conditions, rather than a single disease; (2) The dynamics of gender disparities across developmental stages; and (3) An integrative approach which takes into account additional risk factors (ethnicity, socio-demographic variables, minorities, lifestyle habits etc.). Increasing the awareness of gender-specific medicine in daily practice and in tailored guidelines, already among adolescents, may reduce inequities, facilitate the prediction of future trends and properly address the characteristics and needs of certain subpopulations within each gender.

Different Expression of Duodenal Genes Related to Insulin Resistance Between Nonobese Women and Those with Severe Obesity

OBJECTIVE

The study aim was to identify changes in duodenal gene expression associated with the development of insulin resistance according to the BMI of women.

METHODS

Duodenal samples were assessed by microarray in four groups of women, nonobese women and women with severe obesity, with both low and high insulin resistance.

RESULTS

There was a group of shared downregulated differentially expressed genes (DEGs) related to tissue homeostasis and antimicrobial humoral response in women with higher insulin resistance both with severe obesity and without obesity. In the exclusive DEGs found in severe obesity, downregulated DEGs related to the regulation of the defense response to bacterium and cell adhesion, involving pathways related to the immune system, inflammation, and xenobiotic metabolism, were observed. In the exclusive DEGs from nonobese women with higher insulin resistance, upregulated DEGs mainly related to the regulation of lipoprotein lipase activity, very low-density lipoprotein particle remodeling, lipid metabolic process, antigen processing, and the presentation of peptide antigen were found.

CONCLUSIONS

Independent of BMI, higher insulin resistance was associated with a downregulation of duodenal DEGs mainly related to the immune system, inflammation, and xenobiotic metabolism. Also, intestinal lipoprotein metabolism may have a certain relevance in the regulation of insulin resistance in nonobese women.

Deciphering the Association Between Psoriasis and Obesity: Current Evidence and Treatment Considerations

PURPOSE OF REVIEW

Obesity and psoriasis represent chronic inflammatory states that are interconnected in a vicious cycle, sharing also a degree of synergy. In this review, we aim to decipher the various lines of evidence supporting the bidirectional association between psoriasis and obesity highlighting their pathophysiologic connections as well as we attempt to strategize a therapeutic holistic approach for obese psoriatic patients.

RECENT FINDINGS

Recent meta-analyses have shown that (1) genetically higher BMI increased the odds of psoriasis occurrence; (2) obesity is associated with higher incidence and prevalence of psoriasis as well as psoriasis severity; (3) obesity is associated with lower efficacy to anti-TNF agents and may predict biologic treatment discontinuation; and (4) weight loss through diet and physical exercise may improve pre-existing psoriasis and prevent from de novo psoriasis. Methotrexate, acitretin, and cyclosporine could worsen hypertension, liver steatosis, and dyslipidemia. Since infliximab and ustekinumab are weight adjusted, they may be ideal drugs to treat obese psoriatic patients. IL-17 inhibitors are very effective independently from body weight; however, they tend to present better clearance rates in normal weight patients. There is a paucity on weight data regarding the efficacious IL-23 inhibitors. Apremilast may induce weight loss as an adverse effect presenting also some beneficial metabolic actions. Finally, simvastatin and some antidiabetic drugs could decrease psoriasis severity. More mechanistic, observational studies and well-conducted RCTs are necessary to decipher the enigmatic link between psoriasis and obesity, and to provide evidence-based specific guidelines for the screening and management of obese psoriatic patients.

Adipocytokines: Are they the Theory of Everything?

INTRODUCTION

Adipose tissue secretes various bioactive peptides/proteins, immune molecules and inflammatory mediators which are known as adipokines or adipocytokines. Adipokines play important roles in the maintenance of energy homeostasis, appetite, glucose and lipid metabolism, insulin sensitivity, angiogenesis, immunity and inflammation. Enormous number of studies from all over the world proved that adipocytokines are involved in the pathogenesis of diseases affecting nearly all body systems, which raises the question whether we can always blame adipocytokines as the triggering factor of every disease that may hit the body.

OBJECTIVE

Our review targeted the role played by adipocytokines in the pathogenesis of different diseases affecting different body systems including diabetes mellitus, kidney diseases, gynecological diseases, rheumatologic disorders, cancers, Alzheimer's, depression, muscle disorders, liver diseases, cardiovascular and lung diseases.

METHODOLOGY

We cited more than 33 recent literature reviews that discussed the role played by adipocytokines in the pathogenesis of different diseases affecting different body systems.

CONCLUSION

More evidence is being discovered to date about the role played by adipocytokines in more diseases and extra research is needed to explore hidden roles played by adipokine imbalance on disease pathogenesis.

Is There an Obesity Paradox in Critical Illness? Epidemiologic and Metabolic Considerations

PURPOSE OF REVIEW

Obesity represents a global epidemic with serious implications in public health due to its increasing prevalence and its known association with a high morbidity and mortality burden. However, a growing number of data support a survival benefit of obesity in critical illness. This review summarizes current evidence regarding the obesity paradox in critical illness, discusses methodological issues and metabolic implications, and presents potential pathophysiologic mechanisms.

RECENT FINDINGS

Data from meta-analyses and recent studies corroborate the obesity-related survival benefit in critically ill patients as well as in selected populations such as patients with sepsis and acute respiratory distress syndrome, but not trauma. However, this finding warrants a cautious interpretation due to certain methodological limitations of these studies, such as the retrospective design, possible selection bias, the use of BMI as an obesity index, and inadequate adjustment for confounding variables. Main pathophysiologic mechanisms related to obesity that could explain this phenomenon include higher energy reserves, inflammatory preconditioning, anti-inflammatory immune profile, endotoxin neutralization, adrenal steroid synthesis, renin-angiotensin system activation, cardioprotective metabolic effects, and prevention of muscle wasting. The survival benefit of obesity in critical illness is supported from large meta-analyses and recent studies. Due to important methodological limitations, more prospective studies are needed to further elucidate this finding, while future research should focus on the pathophysiologic role of adipose tissue in critical illness.

Probiotics, Prebiotics, Synbiotics, Postbiotics, and Obesity: Current Evidence, Controversies, and Perspectives

PURPOSE OF REVIEW

In this review, we summarize current evidence on gut microbiome and obesity; we discuss the role of probiotics, prebiotics, synbiotics, and postbiotics in obesity prevention and management; and we highlight and analyze main limitations, challenges, and controversies of their use.

RECENT FINDINGS

Overall, the majority of animal studies and meta-analyses of human studies examining the use of probiotics and synbiotics in obesity has shown their beneficial effects on weight reduction and other metabolic parameters via their involvement in gut microbiota modulation. Bifidobacterium and Lactobacillus strains are still the most widely used probiotics in functional foods and dietary supplements, but next generation probiotics, such as Faecalibacterium prausnitzii, Akkermansia muciniphila, or Clostridia strains, have demonstrated promising results. On the contrary, meta-analyses of human studies on the use of prebiotics in obesity have yielded contradictory results. In animal studies, postbiotics, mainly short-chain fatty acids, may increase energy expenditure through induction of thermogenesis in brown adipose tissue as well as browning of the white adipose tissue. The main limitations of studies on biotics in obesity include the paucity of human studies; heterogeneity among the studied subgroups regarding age, gender, and lifestyle; and use of different agents with potential therapeutic effects in different formulations, doses, ratio and different pharmacodynamics/pharmacokinetics. In terms of safety, the supplementation with prebiotics, probiotics, and synbiotics has not been associated with serious adverse effects among immune-competent individuals, with the exception of the use of probiotics and synbiotics in immunocompromised patients. Further large-scale Randomized Controlled Trials (RCTs) in humans are required to evaluate the beneficial properties of probiotics, prebiotics, synbiotics, and postbiotics; their ideal dose; the duration of supplementation; and the durability of their beneficial effects as well as their safety profile in the prevention and management of obesity.

Physical activity, obesity and sedentary behavior in cancer etiology: epidemiologic evidence and biologic mechanisms

An estimated 30–40% of cancers can be prevented through changes in modifiable lifestyle and environmental risk factors known to be associated with cancer incidence. Despite this knowledge, there remains limited awareness that these associations exist. The purpose of this review article was to summarize the epidemiologic evidence concerning the contribution of physical activity, sedentary behavior, and obesity to cancer etiology and to provide an overview of the biologic mechanisms that may be operative between these factors and cancer incidence. Strong and consistent evidence exists that higher levels of physical activity reduce the risk of six different cancer sites (bladder, breast, colon, endometrial, esophageal adenocarcinoma, gastric cardia), whereas moderate evidence inversely associates physical activity with lung, ovarian, pancreatic and renal cancer, and limited evidence inversely correlates physical activity with prostate cancer. Sedentary behavior, independent of physical activity, has been shown to increase the risk of colon, endometrial, and lung cancers. Obesity is an established risk factor for 13 different cancer sites (endometrial, postmenopausal breast, colorectal, esophageal, renal/kidneys, meningioma, pancreatic, gastric cardia, liver, multiple myeloma, ovarian, gallbladder, and thyroid). The main biologic mechanisms whereby physical activity, sedentary behavior, and obesity are related to cancer incidence include an effect on endogenous sex steroids and metabolic hormones, insulin sensitivity, and chronic inflammation. Several emerging pathways related to oxidative stress, DNA methylation, telomere length, immune function, and gut microbiome are presented. Key recommendations for future research in both the epidemiology and biology of the associations between physical activity, sedentary behavior, obesity, and cancer risk are also provided.

Value of Visceral Fat Area in the Preoperative Discrimination of Peritoneal Metastasis from Gastric Cancer in Patients with Different Body Mass Index: A Prospective Study

Purpose

Although peritoneal metastasis (PM) is associated with poor prognosis in gastric cancer (GC) patients, it is difficult to discriminate preoperatively. Our previous study has demonstrated visceral fat area (VFA) is a better obesity index than body mass index (BMI) in predicting abdominal metastasis. This study aimed to further explore the relationship between obesity and PM.

Patients and Methods

VFA was retrieved for 859 consecutive patients undergoing radical gastrectomy between January 1, 2009, and December 31, 2013. A receiver operating characteristic curve analysis was used to determine the BMI-specific cutoff values for VFA. Univariate and multivariate analyses evaluating the risk factors for PM at different BMI levels were performed.

Results

The optimal cutoff values for VFA were 67.28, 88.03, and 175.32 cm² for low, normal, and high BMI patients, respectively, and 18 (15.52%), 220 (40.15%), and 61 (31.28%) patients were classified as having high VFA in each group. Univariate logistic regression revealed that the association between high VFA and PM was not dependent on BMI (odds ratio [OR]=9.048, P=0.007 for low BMI, OR=3.827, P<0.001 for normal BMI, and OR=2.460, P=0.049 for high BMI). In multivariate logistic regression analysis, high VFA (OR=3.816, P<0.001) and vascular invasion (OR=1.951, P=0.039) were independent risk factors for PM only in the normal BMI group.

Conclusion

VFA only effectively predicted PM for GC patients with normal BMI, rather than those with low and high BMI. More attentions should be paid to those GC patients with high VFA and normal BMI.

The Adipokines in Cancer Cachexia

Cachexia is a devastating pathology induced by several kinds of diseases, including cancer. The hallmark of cancer cachexia is an extended weight loss mainly due to skeletal muscle wasting and fat storage depletion from adipose tissue. The latter exerts key functions for the health of the whole organism, also through the secretion of several adipokines. These hormones induce a plethora of effects in target tissues, ranging from metabolic to differentiating ones. Conversely, the decrease of the circulating level of several adipokines positively correlates with insulin resistance, metabolic syndrome, diabetes, and cardiovascular disease. A lot of findings suggest that cancer cachexia is associated with changed secretion of adipokines by adipose tissue. In agreement, cachectic patients show often altered circulating levels of adipokines. This review reported the findings of adipokines (leptin, adiponectin, resistin, apelin, and visfatin) in cancer cachexia, highlighting that to study in-depth the involvement of these hormones in this pathology could lead to the development of new therapeutic strategies.

Obesity and Cancer: 27-Hydroxycholesterol, the Missing Link

Obesity is currently affecting more than 40% of the Americans, and if it progresses with this rate, soon one out of two Americans will be obese. Obesity is an important risk factor for several disorders including cardiovascular disease, the first cause of death in the United States. Cancer follows as the second deadliest disease, and a link between obesity and cancer has been suggested. However, it is very hard to establish an exact connection between obesity and cancers due to the multifactorial nature of obesity. Hypercholesterolemia is a comorbidity of obesity and also linked to several cancers. Recently a cholesterol metabolite 27-hydroxycholesterol (27HC) was found to be an endogenous selective estrogen receptor modulator (SERM), which opened new doors toward several interesting studies on the role of this molecule in biological disorders. It is speculated that 27HC might be the missing link in the obesity and cancer chain. Here, we explored the effects of 27-hydroxycholesterol on obesity and cancers with a focus on the SERM capacity of 27HC.

New-generation anti-obesity drugs: naltrexone/bupropion and liraglutide. An update for endocrinologists and nutritionists

The prevalence of obesity increases worldwide and has a significant economic impact on health care systems. A comprehensive program of lifestyle modification, including diet, exercise, and behavior therapy is considered the first option for achieving the significant weight loss. However, the intrinsic difficulties associated with maintenance of lifestyle changes contribute to the unsatisfactory long-term outcomes reported and weight regain in the obesity management. In this context, pharmacological approaches are useful to maximize non-pharmacological interventions in the long-term management of obesity. As add-on to lifestyle modification, pharmacological interventions are useful to facilitate clinically weight loss. In the past, anti-obesity drugs were limited. To date, the landscape has changed and naltrexone/bupropion and liraglutide have been recently added as new-generation anti-obesity drugs on obesity treatment and could represent important tools to manage of obesity. Liraglutide is a glucagon-like peptide 1 (GLP-1) receptor agonist that shares 97% homology to native GLP-1 with effects on the limbic system. The treatment with liraglutide 3.0 mg, in combination with a hypocaloric diet and increased physical activity, provides a clinically meaningful weight loss. The combination of naltrexone 32 mg and bupropion 360 mg acts on the mesolimbic reward pathway and the hypothalamic hunger system, two areas of the central nervous system. The combination of naltrexone/bupropion, an adjunct to a hypocaloric diet and increased physical activity, is approved for chronic weight management in adults with obesity or overweight and ≥1 weight-related comorbidity. In the present review, we have focused on the current evidence on two new-generation anti-obesity drugs, naltrexone/bupropion and liraglutide 3.0 mg addressing the main studies that investigated these two new drugs for obesity treatment. Furthermore, evidence on semaglutide, currently in the pipeline for potential future therapeutic use for weight loss, are reported.

Prospective cohort study of metabolic syndrome and endometrial cancer survival

OBJECTIVE

Comorbidities are known to increase endometrial cancer risk, but the separate and combined impact of these risk factors on endometrial cancer survival remains unclear. This study aimed to determine the associations between metabolic syndrome and its components with disease-free survival, overall survival, endometrial cancer-specific survival and recurrence among endometrial cancer survivors.

METHODS

Cases from a population-based case-control study who were diagnosed with primary endometrial cancer between 2002 and 2006 in Alberta, Canada were followed until death or March 20, 2019. Baseline in-person interviews, direct anthropometric measurements and fasting blood samples were used to assess metabolic syndrome (presence of ≥3 of the following: waist circumference ≥ 88 cm, fasting blood glucose ≥100 mg/dL, triglycerides ≥150 mg/dL, high-density lipoprotein cholesterol <50 mg/dL and self-reported hypertension). Cox proportional hazards regression and Fine and Gray competing risk models were used to estimate multivariate-adjusted hazard ratios (95% CI) for these associations.

RESULTS

Among 540 endometrial cancer survivors, 325 had metabolic syndrome at diagnosis and 132 had a recurrence and/or died during the median 14.2 years of follow-up (range: 0.3-16.5 years). In multivariable analyses, being diagnosed with metabolic syndrome (HR = 1.98, 95% CI = 1.07-3.67) and having an elevated waist circumference (≥88 cm; HR = 2.12, 95% CI = 1.18-3.80; HR_{per 5 cm} = 1.21, 95% CI = 1.07-1.36) were associated with worse overall survival. Additionally, increasing waist circumference (per 5 cm) was also associated worse with disease-free survival (HR_{per 5 cm} = 1.11, 95% CI = 1.00-1.24).

CONCLUSION

The metabolic syndrome, in particular central adiposity, were associated with worse overall and disease-free survival in endometrial cancer survivors.

Association of Sex Hormones with Risk of Cancers of the Pancreas, Kidney, and Brain in the UK Biobank Cohort Study

BACKGROUND

There is some evidence to suggest that endogenous levels of sex hormones might influence the etiology of cancers of the pancreas, kidney, and brain, but epidemiologic data are lacking.

METHODS

We evaluated the association of circulating levels of total and free testosterone, and of sex hormone-binding globulin (SHBG), with the risk of cancers of the pancreas, kidney, and brain, and of total and free estradiol with the risk of kidney cancer, in the UK Biobank cohort study (n = 425,793; 225 pancreatic cancers, 749 kidney cancers, 467 brain cancers). Multivariable Cox proportional hazards models were used to estimate HRs and 95% confidence intervals for the associations.

RESULTS

Testosterone and SHBG levels were not associated with risk of pancreatic cancer. Most of the associations for the other two anatomic sites were null. There were inverse associations between total testosterone and brain cancer in men and between SHBG and risk of kidney cancer in the total sample and in women. Estradiol was not associated with the risk of kidney cancer.

CONCLUSIONS

The results of this study provide little support for associations between sex hormones/SHBG and risk of cancers of the pancreas, kidney, and brain. Larger studies are warranted.

IMPACT

Although these results provide little support for roles for sex hormones and SHBG in the etiology of cancers of the pancreas, kidney, and brain, there is a need for studies with larger numbers of cases.

Weight loss normalizes enhanced expression of the oncogene survivin in visceral adipose tissue and blood leukocytes from individuals with obesity

BACKGROUND/OBJECTIVES

Survivin is an oncogene associated with a decrease in apoptosis, an increase in tumor growth, and poor clinical outcome of diverse malignancies. A correlation between obesity, cancer, and survivin is reported in the literature. To date, the impact of weight loss on change in survivin levels is understudied. This study was aimed at: (1) comparing survivin levels in adipose tissue (AT) from lean and obese animal models and evaluating changes after weight loss induced by energy restriction and/or exercise; (2) comparing survivin levels in normal weighted and obese humans and evaluating changes in survivin levels after weight loss induced by a very-low-calorie ketogenic diet (VLCKD) or bariatric surgery in AT and/or blood leukocytes (PBL/PBMCs).

SUBJECTS/METHODS

Survivin expression was evaluated in subcutaneous (SAT) and visceral (VAT) AT derived from animal models of monogenic (Zucker rats) and diet-induced obesity (Sprague Dawley rats and C57BL/6J mice) and after a 4-week weight-loss protocol of energy restriction and/or exercise. Plasma was used to measure the inflammatory status. Survivin expression was also evaluated in PBMCs from patients with obesity and compared with normal weight, in PBLs after VLCKD, and in SAT and/or PBLs after bariatric surgery.

RESULTS

Survivin expression was specifically higher in VAT from obese that lean animals, without differences in SAT. It decreased after weight loss induced by energy restriction and correlated with adiposity and inflammatory markers. In humans, the correlation between being obese and higher levels of survivin was confirmed. In obese subjects, survivin levels were reduced following weight loss after either VLCKD or bariatric surgery. Particularly, a decrease in PBMCs expression (not in SAT one) was found after surgery.

CONCLUSIONS

Weight loss is effective in decreasing survivin levels. Also, PBL/PBMC should be regarded as appropriate mirror of survivin levels in VAT for the identification of an obesity-related protumoral microenvironment.

Obesity promotes gastric cancer metastasis via diacylglycerol acyltransferase 2-dependent lipid droplets accumulation and redox homeostasis

Experimental and molecular epidemiological studies indicate important roles for adipose tissue or high-fat diet (HFD) in tumor growth and metastasis. Gastric cancer (GC) possesses a metastatic predilection for the adipocyte-rich peritoneum. However, the precise molecular relevance of HFD in the peritoneal metastasis of GC remains unclear. Here, we showed that HFD causes obvious fat accumulation and promotes peritoneal dissemination of GC in vivo. Peritoneum-derived adipocytes induces robust lipid droplet (LD) accumulation and fatty acid oxidation in GC cells through transcriptional upregulation of DGAT2 in a C/EBPα-dependent manner and prevents anoikis during peritoneal dissemination. Treatment of GC cells with FAs or coculture with adipocytes induces intracellular formation of LDs and production of NADPH to overcome oxidative stress in vitro. Importantly, overexpression of DGAT2 was identified as an independent predictor of poor survival that promotes lung and peritoneal metastasis of GC, and genetic or pharmacological inhibition of DGAT2, via disruption of lipid droplet formation in a lipid-rich environment, enhances the sensitivity of GC to anoikis in vitro and inhibits peritoneal metastasis in vivo. Overall, our findings highlight the notion that DGAT2 may be a promising therapeutic target in GC with peritoneal implantation and provide some evidence for uncovering the link between obesity and tumor metastasis.

•

Overexpression of DGAT2 is associated with poor prognosis in gastric cancer.

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DGAT2 promotes adipocyte-induced lipid droplet formation and NADPH production.

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DGAT2 promotes cell anoikis resistance by redox modification.

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DGAT2 promotes HFD-induced peritoneal dissemination and lung metastasis in vivo.

The Role of Hyperglycemia in Endometrial Cancer Pathogenesis

Endometrial cancer is one of the most common cancers in women worldwide and its incidence is increasing. Epidemiological evidence shows a strong association between endometrial cancer and obesity, and multiple mechanisms linking obesity and cancer progression have been described. However, it remains unclear which factors are the main drivers of endometrial cancer development. Hyperglycemia and type 2 diabetes mellitus are common co-morbidities of obesity, and there is evidence that hyperglycemia is a risk factor for endometrial cancer independent of obesity. This review aims to explore the association between hyperglycemia and endometrial cancer, and discuss the evidence supporting a role for increased glucose metabolism in endometrial cancer and how this phenotype may contribute to endometrial cancer growth and progression. Finally, the potential role of blood glucose lowering strategies, including drugs and bariatric surgery, for the treatment of this malignancy will be discussed.

The Role of Circulating Adiponectin and SNP276G>T at ADIPOQ Gene in BRCA-mutant Women

BACKGROUND

Environmental factors may influence the lifetime risk of cancer (penetrance) in women with a BRCA mutation.

MATERIALS AND METHODS

In 89 BRCA-mutant women, affected or unaffected by breast/ovarian cancer, we explored serum levels of adipokines and their relation with the polymorphism SNP276G>T as modulators of BRCA penetrance.

RESULTS

Affected women had significantly lower adiponectin than healthy women. Affected women with rs1501299 TT had significantly lower adiponectin and higher leptin than GT and GG genotypes. GT genotype was significantly associated with the disease status [odds ratio (OR)=3.24, 95% confidence interval (95% CI)=1.03-10.17]. Women in the lower tertile of serum adiponectin had a RR of BRCA-associated cancer of 2.80, 95% CI=1.1-7.1 (p for trend=0.03) compared with women in the higher tertile.

CONCLUSION

In the SNP rs1501299 the T allele was significantly associated with lower serum levels of adiponectin in affected women, suggesting that the T allele might be related to cancer.

Life style factors, tumor cell plasticity and cancer stem cells

Cancers are heterogeneous tissues and a layer of heterogeneity is determined by the presence of cells showing stemness traits, known as cancer stem cells (CSCs). Evidence indicates that CSCs are important players in tumor development, progression and relapse. Oncogenic transformation of normal stem cells can give rise to CSCs, but CSCs can also originate from de-differentiation of bulk tumor cells. Thus, factors promoting the increase of normal stem cell pools or stimulating the acquisition of stemness features by tumor cells can have serious consequences on cancer origin and progression. In this review, we will first give an overview of the CSC model of cancer development and we will then discuss the role of life style factors, such as high caloric diet, alcohol drinking and smoking, on the widening of stem cell pools and the induction of CSC features in tumors. Finally, we will discuss some healthy life style factors that can help to prevent cancer.

Overweight and Obesity as Independent Factors for Increased Risk of Hepatocellular Cancer-Related Mortality: A Meta-Analysis

Obesity is related to the amplified risk of developing hepatocellular cancer, but its outcome on hepatocellular cancer-related mortality remains uncertain. Hence, the present study aimed to perform a meta-analysis study to evaluate the relationship between weight and hepatocellular cancer-related deaths. Through a systematic literature search up to December 2019, 7 observational studies with 2,349,834 subjects, 4834 hepatocellular cancer-related deaths were identified reporting relationships between body mass index (BMI), and hepatocellular cancer-related mortality. Odd ratio (OR) with 95% confidence intervals (CIs) was calculated comparing obese, BML > 30kg/m², and overweight, BMI, 25-29.9 kg/m² to subjects with normal BMI using the dichotomous method with a random-effect model. In obese subjects, males (OR, 1.84; 95% CI, 1.25-2.70) and females (OR, 1.26; 95% CI, 1.11-1.44), had higher hepatocellular cancer-related mortality compared to normal BMI subjects. However, overweight males (OR, 1.12; 95% CI, 0.98-1.28) and overweight females (OR, 1.06; 95% CI, 0.95-1.18), did not have such risk with moderate heterogeneity. The extent of increased mortality was higher in obese males compared to obese females. The impact of obesity on hepatocellular cancer-related mortality was observed in all populations with less extant in the black population. Based on this meta-analysis, obesity may have an independent relationship with up to the 1.84-fold risk of hepatocellular cancer-related mortality. This relationship was more pronounced in males than in females. Key teaching pointsBeing overweight is related to the amplified risk of developing hepatocellular cancer.Obesity's affect on hepatocellular cancer-related mortality remains uncertain.Based on this meta-analysis, obesity may have an independent relationship with up to the 1.84-fold risk of hepatocellular cancer-related mortality.This relationship was more pronounced in males than in females.

Circulating omentin level, obesity and cancer risk

The aim of this study was to discuss the association between circulating omentin level and human cancer risk with special reference to obesity.

The protein S100A4 as a novel marker of insulin resistance in prepubertal and pubertal children with obesity

BACKGROUND

S100A4 is a metastasis-associated protein also reported as a promising marker for dysfunctional white adipose tissue (WAT) and insulin resistance (IR) in adult and adolescent populations.

OBJECTIVE

We aimed to evaluate the association between the protein S100A4 and obesity and IR in children and during pubertal development.

DESIGN AND METHODS

The study design consisted of three cross-sectional populations of 249, 11 and 19 prepubertal children respectively (named study population 1, 2 and 3), and a longitudinal population of 53 girls undergoing sexual maturation (study population 4). All subjects were classified into experimental groups according to their sex, obesity and IR status. All study populations counted on anthropometry, glucose, and lipid metabolism, inflammation and cardiovascular biomarkers as well as S100A4 plasma levels measured. The study population 1 was intended as the discovery population in which to elucidate the relationship between Obesity-IR and S100A4 plasma levels in prepubertal children. The cross-sectional populations 2 and 3 further counted on WAT gene expression data for investigating the molecular basis of this association. Instead, the longitudinal study population 4 presented blood whole-genome DNA methylation data at each temporal record, allowing deepening into the Obesity-IR-S1004 relationship during puberty as well as deciphering plausible epigenetic mechanisms altering S100A4 plasma levels.

RESULTS

S100A4 plasma levels were strongly associated with several metabolic and anthropometric outcomes, namely IR, in prepubertal non-diabetic obese children. We also found highly significant positive associations during the course of puberty between the increase in S100A4 levels and the increase in HOMA-IR (P = 0.0003, FDR = 0.005) and insulin levels (P = 0.0003, FDR = 0.005). Methylation in two-enhancer related CpG sites of the S100A4 region (cg07245635 and cg10447638) was associated with IR biomarkers at the prepubertal stage and with longitudinal changes in these measurements. We further reported an association between visceral WAT (vWAT) S100A4 expression and HOMA-IR, insulin levels and BMI Z-Score, but not with circulating S100A4.

CONCLUSIONS

We report for the first time the association of S100A4 with IR and WAT dysfunction in prepubertal populations as well as how the change in plasma S100A4 levels accompanies longitudinal trajectories of IR in children during pubertal development. Moreover, we propose epigenetic changes in two methylation sites and an altered S100A4 vWAT expression as plausible molecular mechanisms underlying this disturbance in obesity.

Potential Impact of BMI on the Aggressiveness of Presentation and Clinical Outcome of Differentiated Thyroid Cancer

BACKGROUND

Obesity is a risk factor for several cancers, including differentiated thyroid cancer (DTC). Moreover, it has also been investigated as a potential risk factor for aggressiveness of DTC, but the data gathered so far are conflicting. The aim of our study was to evaluate the relationship between body mass index (BMI), aggressiveness of DTC at diagnosis, and clinical outcome.

METHODS

We evaluated 1058 consecutive DTC patients treated with total thyroidectomy and enrolled at the time of first radioactive iodine (131I) treatment. Patients were divided into 4 groups based on their BMI: underweight (< 18.5 kg/m2), normal weight (18.5-24.9 kg/m2), overweight (25-29.9 kg/m2), and obese (≥ 30 kg/m2). Histological aggressiveness of DTC at the time of diagnosis and clinical outcome according to 2015 American Thyroid Association (ATA) guidelines were evaluated.

RESULTS

No differences in histological features, ATA risk of recurrence, activity of 131I administered and prevalence of 131I avid metastatic disease after first131I treatment, have been demonstrated among the groups. Furthermore, at the end of follow up (median = 5.7 years), no differences were evident in the number of further treatments performed as well as in the clinical response.

CONCLUSIONS

In our study group of Caucasian subjects, we could not demonstrate any association between BMI and aggressiveness of DTC, neither at the time of diagnosis nor during follow-up. These data indicate that postsurgical assessment and therapeutic attitude for treatment and follow-up of DTC should be based on the class of risk applied to the general population, with no concern for BMI.