Obesity as a risk factor for certain types of cancer

Theory of Food: Unravelling the Lifelong Impact of Childhood Dietary Habits on Adult Food Preferences across Different Diet Groups

The study investigates the behavioral manifestations of the "Theory of Food" (ToF), a novel theoretical framework centered on the early development of food perceptions. The ToF posits that childhood experiences with food shape cognitive networks influencing adult dietary choices. Stemming from the "Theory of Mind," the ToF hypothesizes that individuals construct an associative world of food images and representations mirroring the socio-cognitive world shaped by proper theory of mind development. The study, involving 249 healthy adults, employs the Cognitive Food Preference Questionnaire (CFPQ) and the Adult Food Preference Profile (AFPP) to explore the correlation between childhood and adult food preferences across diet groups (omnivores, vegetarians, and vegans). Results reveal robust correlations in omnivores, varied patterns in vegetarians, and mixed outcomes in vegans. Notably, omnivores show correlations in grains, fast food, dairy products, vegetables, meat, soft drinks, and snack consumption. Vegetarians exhibit correlations in grains, fast food, dairy products, vegetables, snacks, and, surprisingly, meat consumption. Vegans display correlations in grains, fast food, vegetables, and snacks. The study suggests that childhood dietary habits tend to influence adult food choices, offering insights for future research in the field of theory of food (ToF).

An Overview of Cancer in Djibouti: Current Status, Therapeutic Approaches, and Promising Endeavors in Local Essential Oil Treatment

Djibouti, a developing economy, grapples with significant socioeconomic obstacles and the prevalence of infectious pathologies, including certain forms of neoplasms. These challenges are exacerbated by limited access to affordable medical technologies for diagnosis, coupled with a lack of preventive interventions, particularly in disadvantaged areas. The attention devoted to local phytotherapeutic treatments underscores the uniqueness of Djibouti's flora, resulting from its distinctive geographical position. International focus specifically centers on harnessing this potential as a valuable resource, emphasizing the phytoconstituents used to counter pathologies, notably carcinomas. This comprehensive overview covers a broad spectrum, commencing with an examination of the current state of knowledge, namely an in-depth investigation of oncological risk factors. Essential elements of control are subsequently studied, highlighting the fundamental prerequisites for effective management. The significance of dietary habits in cancer prevention and support is explored in depth, while traditional methods are examined, highlighting the cultural significance of indigenous essential oil therapies and encouraging further research based on the promising results.

Maternal obesity driven changes in collagen linearity of breast extracellular matrix induces invasive mammary epithelial cell phenotype

Obesity has been linked with numerous health issues as well as an increased risk of breast cancer. Although effects of direct obesity in patient outcomes is widely studied, effects of exposure to obesity-related systemic influences in utero have been overlooked. In this study, we investigated the effect of multigenerational obesity on epithelial cell migration and invasion using decellularized breast tissues explanted from normal female mouse pups from a diet induced multigenerational obesity mouse model. We first studied the effect of multigenerational diet on the mechanical properties, adipocyte size, and collagen structure of these mouse breast tissues, and then, examined the migration and invasion behavior of normal (KTB-21) and cancerous (MDA-MB-231) human mammary epithelial cells on the decellularized matrices from each diet group. Breast tissues of mice whose dams had been fed with high-fat diet exhibited larger adipocytes and thicker and curvier collagen fibers, but only slightly elevated elastic modulus and inflammatory cytokine levels. MDA-MB-231 cancer cell motility and invasion were significantly greater on the decellularized matrices from mice whose dams were fed with high-fat diet. A similar trend was observed with normal KTB-21 cells. Our results showed that the collagen curvature was the dominating factor on this enhanced motility and stretching the matrices to equalize the collagen fiber linearity of the matrices ameliorated the observed increase in cell migration and invasion in the mice that were exposed to a high-fat diet in utero. Previous studies indicated an increase in serum leptin concentration for those children born to an obese mother. We generated extracellular matrices using primary fibroblasts exposed to various concentrations of leptin. This produced curvier ECM and increased breast cancer cell motility for cells seeded on the decellularized ECM generated with increasing leptin concentration. Our study shows that exposure to obesity in utero is influential in determining the extracellular matrix structure, and that the resultant change in collagen curvature is a critical factor in regulating the migration and invasion of breast cancer cells.

STAT3 signaling in prostate cancer progression and therapy resistance: An oncogenic pathway with diverse functions

The categorization of cancers demonstrates that prostate cancer is the most common malignancy in men and it causes high death annually. Prostate cancer patients are diagnosed mainly via biomarkers such as PSA test and patients show poor prognosis. Prostate cancer cells rapidly diffuse into different parts of body and their metastasis is also a reason for death. Current therapies for prostate cancer patients include chemotherapy, surgery and radiotherapy as well as targeted therapy. The progression of prostate cancer cells is regulated by different factors that STAT3 signaling is among them. Growth factors and cytokines such as IL-6 can induce STAT3 signaling and it shows carcinogenic impact. Activation of STAT3 signaling occurs in prostate cancer and it promotes malignant behavior of tumor cells. Induction of STAT3 signaling increases glycolysis and proliferation of prostate cancer cells and prevents apoptosis. Furthermore, STAT3 signaling induces EMT mechanism in increasing cancer metastasis. Activation of STAT3 signaling stimulates drug resistance and the limitation of current works is lack of experiment related to role of STAT3 signaling in radio-resistance in prostate tumor. Calcitriol, capsazepine and β-elemonic are among the compounds capable of targeting STAT3 signaling and its inhibition in prostate cancer therapy. In addition to natural products, small molecules targeting STAT3 signaling have been developed in prostate cancer therapy.

Effect of Acupuncture on Simple Obesity and Serum Levels of Prostaglandin E and Leptin in Sprague-Dawley Rats

Aim

The study is aimed at investigating the curative effect of acupuncture on simple obesity and its influence on serum levels of prostaglandin E and leptin in Sprague-Dawley (SD) rats.

Methods

In the study, there are 50 male SD rats. We took 10 as healthy controls and fed 40 with a diet of high fat for 8 weeks. After the 40 rat model was established successfully, we fed 10 rats in the model group with a normal diet and treated 10 rats in the acupuncture group by acupuncture. During the experiment, the body fat and body length of rats were measured weekly, and Lee's index was calculated. After the treatment, the levels of leptin, prostaglandin E, C-reactive protein (CRP), triacylglycerol (TG), cholesterol (CHO), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were detected, and the liver fat morphology was observed by electron microscope.

Results

Acupuncture significantly downregulated the serum levels of CRP, TG, CHO, LDL, leptin, and prostaglandin E and upregulated the serum levels of HDL in rats with simple obesity.

Conclusion

On basis of these results, it was found that acupuncture could boost fat metabolism and weight loss by inhibiting the production of leptin and prostaglandin E.

Transformation of SOX9+ cells by Pten deletion synergizes with steatotic liver injury to drive development of hepatocellular and cholangiocarcinoma

SOX9 (Sex-determining region Y Box 9) is a well-characterized transcription factor that is a marker for progenitor cells in various tissues. In the liver, cells delineated by SOX9 are responsible for regenerating liver parenchyma when cell proliferation is impaired following chronic injury. However, whether these SOX9+ cells play a role in liver carcinogenesis has not been fully understood, although high SOX9 expression has been linked to poor survival outcome in liver cancer patients. To address this question, we developed a liver cancer mouse model (PtenloxP/loxP; Sox9-CreERT+; R26RYFP) where tumor suppressor Pten (phosphatase and tensin homolog deleted on chromosome ten) is deleted in SOX9+ cells following tamoxifen injection. In this paper, we employ lineage-tracing to demonstrate the tumorigenicity potential of the Pten-, SOX9+ cells. We show that these cells are capable of giving rise to mixed-lineage tumors that manifest features of both hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (CCA). Our results suggest that PTEN loss induces the transformation of SOX9+ cells. We further show that to activate these transformed SOX9+ cells, the presence of liver injury is crucial. Liver injury, induced by hepatotoxin 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) or high-fat diet (HFD), substantially increases tumor incidence and accelerates liver carcinogenesis from SOX9+ cells in Pten null mice but not in control mice. We further examine the mechanisms underlying tumor formation in this model to show that concurrent with the induction of niche signal (i.e., Wnt signaling), liver injury significantly stimulates the expansion of tumor-initiating cells (TICs). Together, these data show that (1) SOX9+ cells have the potential to become TICs following the primary transformation (i.e. Pten deletion) and that (2) liver injury is necessary for promoting the activation and proliferation of transformed SOX9+ cells, resulting in the genesis of mixed-lineage liver tumors.

LDL cholesterol promotes the proliferation of prostate and pancreatic cancer cells by activating the STAT3 pathway

Hypercholesterolemia has been found to be closely linked with a significant increase in both cancer incidence and mortality. However, the exact correlation between serum cholesterol levels and cancer has not been completely deciphered. Here we analyzed the effect of low-density lipoprotein (LDL) cholesterol on prostate and pancreatic cancer cells. We noted that LDL induced a substantial STAT3 activation and JAK1, JAK2, Src activation in diverse prostate and pancreatic tumor cells. Moreover, LDL promoted cancer cell proliferation, migration, and invasion as well as upregulated the expression of diverse oncogenic gene products. However, deletion of LDL-activated STAT3 in LNCaP and PANC-1 cells and reduced LDL-induced cell viability. Simvastatin (SV) treatment also alleviated LDL-induced cell viability and migration ability in both the prostate and pancreatic tumor cells. These results demonstrate that LDL-induced STAT3 activation may exert a profound effect on the proliferation and survival of tumor cells.

Obesity and esophageal cancer: GERD, Barrett´s esophagus, and molecular carcinogenic pathways

INTRODUCTION

Increases in the rates of esophageal adenocarcinoma (EAC) have paralleled rises in the prevalence of overweight and obesity. Despite not being fully understood, obesity-related EAC seems to have different carcinogenic pathways.

AREAS COVERED

This comprehensive review will thoroughly evaluate the current literature, describing the underlying mechanisms that help understanding the strong association between obesity and esophageal cancer.

EXPERT COMMENTARY

The risk of esophageal cancer among obese individuals could be partially explained by several factors: high prevalence of GERD; linear association between central adiposity and Barrett´s esophagus development; low levels of adiponectin and high levels of leptin that alter cell proliferation processes; insulin-resistant state that creates a tumorigenesis environment; and changes in the esophageal microbiota due to unhealthy dietary habits that promote carcinogenesis. In addition, a large proportion of obese patients are undergoing sleeve gastrectomy which can worsen GERD or cause de novo reflux, esophagitis, and Barrett´s metaplasia.

Treating cancer with phosphatidylinositol-3-kinase inhibitors: increasing efficacy and overcoming resistance

The discovery of the phosphatidylinositol-3-kinase (PI3K) pathway was a major advance in understanding growth factor signaling. The high frequency of PI3K pathway mutations in many cancers has encouraged a new field targeting cancer driver mutations. Although there have been many successes, targeting PI3K itself has proven challenging, in part because of its multiple isoforms with distinct roles. Despite promising preclinical results, development of PI3K inhibitors as pharmacologic anticancer agents has been limited by modest single-agent efficacy and significant adverse effects. If we could overcome these limitations, PI3K inhibitors would be a powerful cancer-fighting tool. Data from phase III clinical trials yields insight into some of the problems with PI3K inhibitors. Recent advances have shed light on the mechanisms of tumor resistance to PI3K inhibitors via feedback pathways that cause elevated insulin levels that then activate the same PI3K pathways that are the targets of inhibition. Improving our understanding of the complex regulatory feedback pathways that activate in response to PI3K inhibition will reveal ways to increase the efficacy of PI3K inhibitors and reduce adverse effects, increasing the usefulness of this class as a treatment option for multiple cancer types.

Use of various obesity measurement and classification methods in occupational safety and health research: a systematic review of the literature

BACKGROUND

This study systematically examined obesity research in occupational safety and health regarding the use of various obesity measurement and classification methods.

METHODS

A systematic search of the PubMed database on English language publications from 2000 to 2015 using related keywords and search of citations resulted in selection of 126 studies. They were categorized into two groups based on their main research question: 1) general physical or mental work-related functioning; and 2) task or body part specific functioning.

RESULTS

Regardless of the study group, body mass index (BMI) was the most frequently used measure. Over 63% of the studies relied solely on BMI to define obesity. In only 22% of the studies, body fat was directly measured by methods such as dual energy x-ray absorptiometry. Abdominal obesity was defined using waist circumference in recent years, and waist-hip ratio in earlier years. Inconsistent cut-offs have also been used across studies investigating similar topics.

CONCLUSIONS

Few authors acknowledged the limitations of using indirect obesity measures. This is in part due to the limited understanding of some occupational safety and health researchers regarding the complex issues surrounding obesity classification and also the mixed recommendations over the past 2-3 decades and across populations. Efforts need to be made to promote appropriate obesity measurement and reporting in this field.

Cancer, the mind and the person: what we know about the causes of cancer

At a time when patients are challenged to cope adaptively with both the diagnosis and treatment of cancer, clinicians need to respond appropriately to the many inevitable questions about the causes of cancer and contributing factors, including ‘Is this my fault?’. The evidence guiding answers to such questions has been confounded by many methodological challenges, but personality, stress and life events are no longer considered causes of cancer. However, social isolation, untreated depression and social deprivation continue to influence quality of life and reduce cancer survival times. Psychiatry might play a role in promoting lifestyle changes that reduce the risk of cancer, but more importantly it can influence disease progression by optimising patients' adaptation to the many challenges that cancer brings.

Metabesity and urological cancers

Metabolic syndrome is one of today's most important health problems. Due to increased prevalence of metabolic syndrome in society, studies done on this topic have increased in number. Although metabolic syndrome was previously considered to be important only for cardiovascular health, it has been learned that with new data, human health is compromised more thoroughly by metabolic syndrome and is also a danger to malignancy. As a result, a new definition in the form of metabesity has been introduced. In this review, available information on metabesity and urological cancers is presented.

In middle-aged and old obese patients, training intervention reduces leptin level: A meta-analysis

BACKGROUND

Leptin is one of the major adipokines in obesity that indicates the severity of fat accumulation. It is also an important etiological factor of consequent cardiometabolic and autoimmune disorders. Aging has been demonstrated to aggravate obesity and to induce leptin resistance and hyperleptinemia. Hyperleptinemia, on the other hand, may promote the development of age-related abnormalities. While major weight loss has been demonstrated to ameliorate hyperleptinemia, obese people show a poor tendency to achieve lasting success in this field. The question arises whether training intervention per se is able to reduce the level of this adipokine.

OBJECTIVES

We aimed to review the literature on the effects of training intervention on peripheral leptin level in obesity during aging, in order to evaluate the independent efficacy of this method. In the studies that were included in our analysis, changes of adiponectin levels (when present) were also evaluated.

DATA SOURCES

3481 records were identified through searching of PubMed, Embase and Cochrane Library Database. Altogether 19 articles were suitable for analyses.

STUDY ELIGIBILITY CRITERIA

Empirical research papers were eligible provided that they reported data of middle-aged or older (above 45 years of age) overweight or obese (body mass index above 25) individuals and included physical training intervention or at least fitness status of groups together with corresponding blood leptin values.

STATISTICAL METHODS

We used random effect models in each of the meta-analyses calculating with the DerSimonian and Laird weighting methods. I-squared indicator and Q test were performed to assess heterogeneity. To assess publication bias Egger's test was applied. In case of significant publication bias, the Duval and Tweedie's trim and fill algorithm was used.

RESULTS

Training intervention leads to a decrease in leptin level of middle-aged or older, overweight or obese male and female groups, even without major weight loss, indicated by unchanged serum adiponectin levels. Resistance training appears to be more efficient in reducing blood leptin level than aerobic training alone.

CONCLUSIONS

Physical training, especially resistance training successfully reduces hyperleptinemia even without diet or major weight loss.

Orally Administered Berberine Modulates Hepatic Lipid Metabolism by Altering Microbial Bile Acid Metabolism and the Intestinal FXR Signaling Pathway

Previous studies suggest that the lipid-lowering effect of berberine (BBR) involves actions on the low-density lipoprotein receptor and the AMP-activated protein kinase signaling pathways. However, the implication of these mechanisms is unclear because of the low bioavailability of BBR. Because the main action site of BBR is the gut and intestinal farnesoid X receptor (FXR) plays a pivotal role in the regulation of lipid metabolism, we hypothesized that the effects of BBR on intestinal FXR signaling pathway might account for its pharmacological effectiveness. Using wild type (WT) and intestine-specific FXR knockout (FXR^int-/-) mice, we found that BBR prevented the development of high-fat-diet-induced obesity and ameliorated triglyceride accumulation in livers of WT, but not FXR^int-/- mice. BBR increased conjugated bile acids in serum and their excretion in feces. Furthermore, BBR inhibited bile salt hydrolase (BSH) activity in gut microbiota, and significantly increased the levels of tauro-conjugated bile acids, especially tauro-cholic acid(TCA), in the intestine. Both BBR and TCA treatment activated the intestinal FXR pathway and reduced the expression of fatty-acid translocase Cd36 in the liver. These results indicate that BBR may exert its lipid-lowering effect primarily in the gut by modulating the turnover of bile acids and subsequently the ileal FXR signaling pathway. In summary, we provide the first evidence to suggest a new mechanism of BBR action in the intestine that involves, sequentially, inhibiting BSH, elevating TCA, and activating FXR, which lead to the suppression of hepatic expression of Cd36 that results in reduced uptake of long-chain fatty acids in the liver.

Immunohistochemical Expression of Leptin in Non Melanoma Skin Cancer

INTRODUCTION

Obesity in adults is associated with numerous health disorders including some forms of cancer. Various epidemiological studies have found a link between excess adiposity and malignant melanoma; however, the association with non melanoma skin cancer is questionable. Leptin is a hormone produced mainly by the adipose tissue and its serum level may reflect body mass index. Leptin is reported to promote proliferation and angiogenesis and deregulate apoptosis, therefore facilitates the process of carcinogenesis.

AIM

The current study tried to assess leptin localization and expression in non melanoma skin cancer to verify its possible role in pathogenesis of this cancer.

MATERIALS AND METHODS

This study was carried out on 13 Basal Cell Carcinoma (BCC) cases and 14 Squamous Cell Carcinoma (SCC) cases together with 19 normal skin biopsies as a control group using immunohistochemical method.

RESULTS

Leptin was expressed in 52.6% of the normal epidermis with pure cytoplasmic and both cytoplasmic and nuclear staining patterns. All cases of SCC (100%) and two cases of BCC (15.4%) showed leptin expression in tumour cells whereas nuclear expression was in favour of SCC. Stromal expression of leptin was seen in both SCC (57.1%) and BCC (38.5%) without significant differences. Percentage of leptin expression by tumour cells in SCC showed positive linear correlation with tumour size (p=0.02) and microvessel density (p=0.000). Stromal expression of leptin in SCC was associated with large tumour size (p=0.04), advanced stage (p=0.01) and tumours arising in sites other than head and neck (p=0.01).

CONCLUSION

Leptin could have a more important role in pathogenesis of cutaneous SCC rather than BCC that may reflect the trivial role of obesity in induction of BCC. The expression of leptin by tumour and stromal cells of SCC could co-operate in its progression by promoting angiogenesis with subsequently acquiring large tumour size and then advanced stage.

Lifelong exposure to dietary isoflavones reduces risk of obesity in ovariectomized Wistar rats

SCOPE

Traditional Asian diet rich in soy isoflavones (ISOs) is discussed to be linked to a lower obesity prevalence. In lifelong and short-term exposure scenarios we investigated effects of an ISO-rich diet on the body composition and development of obesity in female rats.

METHODS AND RESULTS

Female Wistar rats grew up on ISO-free or ISO-rich control diet (CON ISO: 467 mg/kg diet). Starting postnatal day 83, ovariectomized and intact animals received high calorie Western diet (WD) in the absence or presence of ISO (WD ISO: 431 mg/kg diet) for 12 weeks to induce obesity or maintained on respective control diet (CON). One group starting ISO exposure after ovariectomy mimics short-term ISO exposure in postmenopausal Western women. Lifelong but not short-term ISO exposure resulted in reduced body weight, visceral fat mass, serum leptin, and smaller adipocytes. ISO decreased hepatic SREBP-1c, ACC, FAS, and PPARγ mRNA expression in nonobese animals. Moreover, ovariectomy reduced skeletal muscle weight, which was antagonized by both short-term and lifelong ISO exposure.

CONCLUSION

Our results indicate that in female rats lifelong but not short-term ISO intake reduces the risk to develop obesity. Furthermore, lifelong and short-term ISO exposure may antagonize loss of skeletal muscle mass induced by ovariectomy.

Cardiorespiratory fitness in survivors of cervical, endometrial, and ovarian cancers: The Cooper Center Longitudinal Study

BACKGROUND

Cardiorespiratory fitness (CRF), a strong predictor of mortality, is impaired among cancer patients. There is limited data, however, regarding CRF levels in women diagnosed with gynecologic cancers.

METHODS

We compared CRF among ovarian, endometrial, and cervical cancer cases (n=89) to age-matched controls (n=89) in the Cooper Center Longitudinal Study (CCLS). CRF was evaluated by a maximal treadmill exercise tolerance test using a modified-Balke protocol. Conditional logistic regression was used to test for case-control differences in cardiorespiratory fitness, after controlling for age and body mass index, and adhering to the matched pairs design.

RESULTS

The mean ages of cancer cases and controls were 50.9 years and 51.1 years, respectively (p=0.81). Peak METs (1 MET=3.5 mL kg(-1)min(-1)) were 9.2 ± 2.0 in cancer cases compared to 10.0 ± 2.2 in controls (p=0.03). When stratifying by type of cancer, peak METs were 8.9 ± 2.2, 8.4 ± 1.9, 9.5 ± 2.0 for patients with ovarian, endometrial, and cervical cancer, respectively. A gynecological cancer diagnosis was associated with greater odds of having 1-MET lower CRF compared to controls (OR 1.31, 95% CI: 1.05-1.64, p=0.018), after controlling for age and BMI.

CONCLUSION

Gynecologic cancer survivors were more likely to have a 1-MET lower CRF than controls. Given a 1-MET change in CRF is associated with a significant, we advocate for more robust research regarding CRF in gynecologic cancer patients.

Long-term hyperphagia and caloric restriction caused by low- or high-density husbandry have differential effects on zebrafish postembryonic development, somatic growth, fat accumulation and reproduction

In recent years, the zebrafish (Danio rerio) has emerged as an alternative vertebrate model for energy homeostasis and metabolic diseases, including obesity and anorexia. It has been shown that diet-induced obesity (DIO) in zebrafish shares multiple pathophysiological features with obesity in mammals. However, a systematic and comprehensive analysis of the different pathways of energy expenditure in obese and starved fish had been missing thus far. Here, we carry out long-term ad libitum feeding (hyperphagia) and caloric restriction studies induced by low- or high-density husbandry, respectively, to investigate the impact of caloric intake on the timing of scale formation, a crucial step of postembryonic development and metamorphosis, and on somatic growth, body weight, fat storage and female reproduction. We show that all of them are positively affected by increased caloric intake, that middle-aged fish develop severe DIO, and that the body mass index (BMI) displays a strict linear correlation with whole-body triglyceride levels in adult zebrafish. Interestingly, juvenile fish are largely resistant to DIO, while BMI and triglyceride values drop in aged fish, pointing to aging-associated anorexic effects. Histological analyses further indicate that increased fat storage in white adipose tissue involves both hyperplasia and hypertrophy of adipocytes. Furthermore, in ovaries, caloric intake primarily affects the rate of oocyte growth, rather than total oocyte numbers. Finally, comparing the different pathways of energy expenditure with each other, we demonstrate that they are differentially affected by caloric restriction / high-density husbandry. In juvenile fish, scale formation is prioritized over somatic growth, while in sexually mature adults, female reproduction is prioritized over somatic growth, and somatic growth over fat storage. Our data will serve as a template for future functional studies to dissect the neuroendocrine regulators of energy homeostasis mediating differential energy allocation.

Breast Cancer Risk Associated with Estrogen Exposure and Truncating Mutation Location in BRCA1/2 Carriers

BACKGROUND

Mutations in BRCA1/2 confer a high risk of breast cancer, but literature values of this risk vary. A genotype-phenotype correlation has been found in both genes, and the effect of reproductive factors differs according to mutation location. Therefore, we hypothesize that such a variation may exist for other factors related to estrogen exposure.

METHODS

We used a weighted Cox regression model to assess variation in breast cancer risk with these factors using location of mutation in homogeneous breast cancer risk region of BRCA1/2 in the GENEPSO study.

RESULTS

We found that late age at menarche reduced breast cancer risk by 31% and that among BRCA1 carriers, a long or a short menstrual cycle increased risk (by 65% and 73%, respectively). Among premenopausal women, overweight was associated with a 45% decrease in risk whereas underweight was associated with an increased risk (HR, 2.40). A natural menopause, mainly after age 50, was associated with a high breast cancer risk (HR, 2.46), and a significant interaction between menopause status and the location of mutations was found leading up to 10% variation in absolute risk according to the age at menopause.

CONCLUSIONS

As observed in the general population, a late menarche, a long or a short menstrual cycle, over- or underweight, and being postmenopausal were associated with breast cancer risk in BRCA1/2 carriers. The association with the menopause was observed only when the mutation was located in the "high-risk" zones.

IMPACT

Taking into account modifier factors, location of mutation might be important for the clinical management of BRCA1/2 mutation carriers.

Leptin influences estrogen metabolism and accelerates prostate cell proliferation

AIM

The present study was designed to investigate the effect of leptin on estrogen metabolism in prostatic cells.

MAIN METHODS

Malignant (PC-3) and benign (BPH-1) human prostate cells were treated with 17-β-hydroxyestradiol (1 μM) alone or in combination with leptin (0.4, 4, 40 ng/ml) for 72 h. Cell proliferation assay, immunocytochemical staining of estrogen receptor (ER), liquid chromatography-tandem mass spectrometry method (LC-MS) and semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) were used.

KEY FINDINGS

Cell proliferation assay demonstrated that leptin caused significant growth potentiation in both cells. Immunocytochemical staining showed that leptin significantly increased the expression of ER-α and decreased that of ER-β in PC-3 cells. LC-MS method revealed that leptin increased the concentration 4-hydroxyestrone and/or decreased that of 2-methoxyestradiol, 4-methoxyestradiol and 2-methoxyestrone. Interestingly, RT-PCR showed that leptin significantly up-regulated the expression of aromatase and cytochrome P450 1B1 (CYP1B1) enzymes; however down-regulated the expression of catechol-o-methyltransferase (COMT) enzyme.

SIGNIFICANCE

These data indicate that leptin-induced proliferative effect in prostate cells might be partly attributed to estrogen metabolism. Thus, leptin might be a novel target for therapeutic intervention in prostatic disorders.

Obesity and cancer: the role of vitamin D

Background

It is estimated that 20% of all cancer cases are caused by obesity. Vitamin D is thought to be one of the mechanisms underlying this association. This review aims to summarise the evidence for the mediating effect of vitamin D on the link between obesity and cancer.

Methods

Three literature searches using PubMed and Embase were conducted to assess whether vitamin D plays an important role in the pathway between obesity and cancer: (1) obesity and cancer; (2) obesity and vitamin D; and (3) vitamin D and cancer. A systematic review was performed for (1) and (3), whereas a meta-analysis including random effects analyses was performed for (2).

Results

(1) 32 meta-analyses on obesity and cancer were identified; the majority reported a positive association between obesity and risk of cancer. (2) Our meta-analysis included 12 original studies showing a pooled relative risk of 1.52 (95% CI: 1.33-1.73) for risk of vitamin D deficiency (<50 nmol/L) in obese people (body mass index >30 kg/m²). (3) 21 meta-analyses on circulating vitamin D levels and cancer risk were identified with different results for different types of cancer.

Conclusion

There is consistent evidence for a link between obesity and cancer as well as obesity and low vitamin D. However, it seems like the significance of the mediating role of vitamin D in the biological pathways linking obesity and cancer is low. There is a need for a study including all three components while dealing with bias related to dietary supplements and vitamin D receptor polymorphisms.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2407-14-712) contains supplementary material, which is available to authorized users.

Measuring stages of change, perceived barriers and self efficacy for physical activity in Saudi Arabia

BACKGROUND

The benefits of physical activity are well established and recognized to prevent adults from many chronic diseases and particularly some forms of cancers.

OBJECTIVES

The present study was conducted to investigate the present status of physical activity among Saudi adults in Al-Ahsa, and to examine the association between the stages of change for physical activity and perceived barriers, and self efficacy.

METHODS

A cross- sectional study of 242 subjects (118 males and 124 females) attending health centers aged between 20-56 years, were personally interviewed for demographic data, anthropometric measurement, physical activity level, stages of change for physical activity, self efficacy and perceived barriers.

RESULTS

Forty eight percent of the females were overweight and 16.9% of the males were obese with no significant difference between the genders for BMI categories. More than half of the females were inactive and 39% of the males were physically active with a significant difference (P=0.007). Twenty percent of the males were in maintenance stage, while similar percentage of the females were in contemplation stage. However the majority of the subjects were in pre-contemplation stage with a significant difference across the stages. Males had a higher mean score of self efficacy and less external barriers of physical activity. The major barrier among the females was lack of time (7.2±1.4) and in the males, lack of motivation (7.7±1.4). The females had less internal (21.2±3.8) barriers comparable to the males (23.08±4.7). Both genders had a significant relationship between stages of changes of physical activity and perceived barriers (internal and external), but in the females no significant difference across the stages was observed for self efficacy unlike the males who had a significant difference for self efficacy and self efficacy categories.

CONCLUSION

The present study provided useful data on stages of change for physical activity and some psychosocial factors (self efficacy and perceived barriers) that can help to tailor strategies aiming at increasing physical activity level according to self efficacy and to the barriers detected, to prevent many chronic diseases including certain types of cancer in Saudi Arabia.

Abdominal obesity, independent from caloric intake, accounts for the development of intestinal tumors in Apc(1638N/+) female mice

To determine whether visceral fat (VF), independent of other confounders, is causally linked to intestinal tumorigenesis, we surgically removed visceral fat in Apc(1638/N+) mice. At 15 weeks of age, male and female Apc(1638/N+) mice were randomized to one of three groups: ad libitum, visceral fat removal (VF-) and ad libitum fed, or caloric restriction, and were studied for effects on tumorigenesis and survival. As compared with ad libitum, VF- and caloric restriction reduced macroadenomas to a similar extent (P < 0.05), but only caloric restriction significantly improved survival (P < 0.05). Given that a significant group × gender interaction was observed, we next examined males and females separately. In females, macroadenomas were markedly attenuated by VF- (1.33 ± 0.23 mean ± SE; P < 0.05), but not by caloric restriction (2.35 ± 0.25; P = 0.71), as compared with ad libitum (2.50 ± 0.34). In males, however, caloric restriction (1.71 ± 0.26; P < 0.01), but not VF- (2.94 ± 0.42; P = 0.29), reduced macroadenomas, as compared with ad libitum males (3.47 ± 0.30). In females, both VF- (P = 0.05) and caloric restriction (P < 0.01) improved survival, but not in male mice (P = 0.15). The benefits observed with caloric restriction were consistent with favorable metabolic adaptations, but protection conferred in VF- females was despite lower adiponectin levels (P < 0.05), and failure to reduce body mass, total adiposity, glucose, insulin, leptin, and chemokine (C-X-C motif) ligand 1 (CXCL-1) levels. In conclusion, these data provide the first causal evidence linking visceral fat to intestinal cancer risk, and suggest that factors, other than known metabolic mediators, may impact tumor development. Furthermore, these data emphasize that strategies designed to deplete visceral fat stores in humans should be considered in the prevention of intestinal cancer. Cancer Prev Res; 6(3); 177-87. ©2012 AACR.

Percentage of body fat assessment using bioelectrical impedance analysis and dual-energy X-ray absorptiometry in a weight loss program for obese or overweight Chinese adults

The current study aimed to compare the estimates of body fat percentage (%BF) by performing bioelectrical impedance analysis (BIA) and dual energy X-ray absorptiometry (DXA) in a sample of obese or overweight Chinese adults who participated in a weight-loss randomized control trial stratified by gender to determine whether or not BIA is a valid measurement tool. Among 189 adults [73 males, 116 females; age = 41 to 74 years; mean body mass index (BMI) = 27.3 kg/m(2)], assessments of %BF at the baseline and six months from the baseline were conducted by performing BIA and DXA. Bland-Altman analyses and multiple regression analyses were used to assess the relationships between %BFBIA and %BFDXA. Compared with DXA, BIA underestimated %BF [in males: 4.6, -2.4 to 11.7 (mean biases, 95% limit of agreement) at the baseline, 1.4, -7.4 to 10.2 at the endpoint, and 3.2, -4.8 to 11.3 in changes; in females: 5.1, -2.4 to 12.7; 2.2, -6.1 to 10.4; and 3.0, -4.8 to 10.7, respectively]. For males and females, %BFDXA proved to be a significant predictor of the difference between DXA and BIA at the baseline, the endpoint, and in changes when BMI and age were considered (in males: p<0.01 and R (2) = 23.1%, 24.1%, 20.7%, respectively; for females: p<0.001 and R (2) = 40.4%, 48.8%, 25.4%, respectively). The current study suggests that BIA provides a relatively accurate prediction of %BF in individuals with normal weight, overweight, or obesity after the end of weight-loss program, but less accurate prediction of %BF in obese individuals at baseline or weight change during the weight-loss intervention program.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, The Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, the Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Obesity and US mortality risk over the adult life course

In this study, we analyzed age variation in the association between obesity status and US adult mortality risk. Previous studies have found that the association between obesity and mortality risk weakens with age. We argue that existing results were derived from biased estimates of the obesity-mortality relationship because models failed to account for confounding influences from respondents' ages at survey and/or cohort membership. We employed a series of Cox regression models in data from 19 cross-sectional, nationally representative waves of the US National Health Interview Survey (1986-2004), linked to the National Death Index through 2006, to examine age patterns in the obesity-mortality association between ages 25 and 100 years. Findings suggest that survey-based estimates of age patterns in the obesity-mortality relationship are significantly confounded by disparate cohort mortality and age-related survey selection bias. When these factors are accounted for in Cox survival models, the obesity-mortality relationship is estimated to grow stronger with age.

Clinical practice guidelines for the perioperative nutritional, metabolic, and nonsurgical support of the bariatric surgery patient--2013 update: cosponsored by American Association of Clinical Endocrinologists, the Obesity Society, and American Society for Metabolic & Bariatric Surgery

The development of these updated guidelines was commissioned by the AACE, TOS, and ASMBS Board of Directors and adheres to the AACE 2010 protocol for standardized production of clinical practice guidelines (CPG). Each recommendation was re-evaluated and updated based on the evidence and subjective factors per protocol. Examples of expanded topics in this update include: the roles of sleeve gastrectomy, bariatric surgery in patients with type-2 diabetes, bariatric surgery for patients with mild obesity, copper deficiency, informed consent, and behavioral issues. There are 74 recommendations (of which 56 are revised and 2 are new) in this 2013 update, compared with 164 original recommendations in 2008. There are 403 citations, of which 33 (8.2%) are EL 1, 131 (32.5%) are EL 2, 170 (42.2%) are EL 3, and 69 (17.1%) are EL 4. There is a relatively high proportion (40.4%) of strong (EL 1 and 2) studies, compared with only 16.5% in the 2008 AACE-TOS-ASMBS CPG. These updated guidelines reflect recent additions to the evidence base. Bariatric surgery remains a safe and effective intervention for select patients with obesity. A team approach to perioperative care is mandatory with special attention to nutritional and metabolic issues.

Effect of physical activity and sedentary behavior on serum prostate-specific antigen concentrations: results from the National Health and Nutrition Examination Survey (NHANES), 2003-2006

OBJECTIVE

To examine the association between accelerometer-derived sedentary and physical activity and prostate-specific antigen (PSA) in a nationally representative sample of men in the United States.

PARTICIPANTS AND METHODS

Data from the 2003-2004 and 2005-2006 National Health and Nutrition Examination Survey cycles were used in the present study, with data from 1672 adult male participants used in the analyses. The manuscript was prepared between July 7, 2012, and September 26, 2012. Sedentary and physical activity was objectively measured using an accelerometer. Covariates included various demographic, dietary, biological, and immunologic variables including age, height, weight, body mass index, race/ethnicity, marital status, education, and poverty-income ratio; dietary fiber, fat, protein, and carbohydrate intake and total energy intake; vitamin C and vitamin E; alcohol intake; medication use; concentrations of cotinine, total cholesterol, and high-density lipoprotein cholesterol; blood pressure (elevated or not elevated); diabetes; C-reactive protein; and white blood cell count and number of basophils and eosinophils.

RESULTS

Only after controlling for all covariates, for every 1-hour increase in sedentary behavior, participants were 16% more likely to have an elevated PSA concentration (odds ratio, 1.16 [95% CI, 1.06-1.27]; P=.001). For every 1-hour increase in light physical activity, participants were 18% less likely to have an elevated PSA concentration (odds ratio, 0.82 [95% CI, 0.68-1.00]; P=.05).

CONCLUSION

Individuals who engage in more sedentary behavior and lower levels of light physical activity have higher PSA concentrations. Future studies are needed to better identify the potential underlying mechanisms delineating the association between sedentary and physical activity and PSA concentration.

A cross-sectional analysis of the association between night-only or rotating shift work and overweight/obesity among female nurses and midwives

OBJECTIVE

To examine the associations between shift work types and overweight/obesity among female nurses and midwives.

METHODS

A cross-sectional study. Measurement included exposure variables: rotating shift work and night-only shift work; outcome variables: overweight and obesity; and potential confounding and associated variables: modifiable lifestyle factors, general health status, menopausal status, and work pattern.

RESULTS

Among the 2086 participants, almost 60% were overweight/obese (31.7% overweight; 27.1% obese). After we adjusted the selected confounders, we found that rotating shift workers were 1.02 times more likely to be overweight/obese than day workers (P = 0.007; 95% confidence interval [95% CI], 1.004 to 1.03; and P = 0.02; 95% CI: 1.004 to 1.04, respectively). Night-only shift work was found to be significantly associated with obesity only (P = 0.031; relative risk, 1.02; 95% CI, 1.002 to 1.04).

CONCLUSIONS

Rotating shift work was associated with both overweight and obesity; and night-only shift work was associated with obesity, not overweight.

Body composition, C-reactive protein, carotid artery remodeling and subclinical atherosclerosis in a general Taiwanese population

Obesity, an escalating problem worldwide, increases the risk of serious disease, particularly atherosclerosis. A community-based cross-sectional study was designed to screen for undetected atherosclerosis. High-sensitivity C-reactive protein (hs-CRP), the presence of the metabolic syndrome (MetS), and ultrasound studies to detect fatty liver and measure carotid intimal-medial thickness were performed. A total of 1,005 subjects (595 men and 410 women; mean age of 52.4 ± 11.1 years) were included in the final study cohort. 237 subjects (23.7%) fulfilled National Cholesterol Education Program Adult Treatment Panel ATP-III criteria for MetS. Significant differences between female and male subjects were noted in body mass index (BMI), % body fat mass (Fat%), waist-to-hip ratio, waist circumference, fasting glucose levels, triglyceride levels, fatty liver, and carotid artery changes (P < 0.05). When female subjects were classified by hs-CRP levels, significant differences were reported among the three groups in age, BMI, Fat%, waist-to-hip ratio, waist circumference, blood pressure, fasting glucose, HDL, triglycerides, fatty liver grade and common carotid artery changes (P < 0.05). In this study, high hs-CRP was associated with increased cholesterol and cardiovascular changes supporting the idea that it may be a useful biomarker for detecting early asymptomatic vascular and coronary heart disease resulting from obesity.

The adipocyte-derived hormone leptin has proliferative actions on androgen-resistant prostate cancer cells linking obesity to advanced stages of prostate cancer

Background. Because obesity may be a risk factor for prostate cancer, we investigated proliferative effects of adipocytes-derived hormone leptin on human prostate cancer cells and assessed the role of mitogen-activated protein kinase (MAPK) signaling pathway in mediating these actions. Material and Methods. Three human prostate cancer cell lines were treated with increasing doses of recombinant leptin. Cell growth was measured under serum-free conditions using a spectrophotometric assay. Further, Western blotting was applied to detect the phosphorylation of an ERK1/2, and a specific inhibitor of MAPK (PD98059; 40 μM) was used. Results. In both androgen-resistant cell lines DU145 and PC-3, cell growth was dose-dependently increased by leptin after 24 hrs and 48 hrs of incubation, whereas leptin's proliferative effects on androgen-sensitive cell line LNCaP was less pronounced. Further, leptin caused dose-dependent ERK1/2 phosphorylation in both androgen-resistant cell lines, and pretreatment of these cells with PD98059 inhibited these responses. Conclusions. Leptin may be a potential link between obesity and risk of progression of prostate cancer. Thus, studies on leptin and obesity association to prostate cancer should differentiate patients according to androgen sensitivity.

Leptin promotes human glioblastoma growth through activating Signal Transducers and Activators of Transcription 3 signaling

Leptin plays an important role in cancer development and progression. However, its role on human glioblastoma cell line U87 growth and the underlying mechanism remains unexplored. In this study, we assessed the effect of leptin on U87 cells proliferation in vitro and in vivo, elucidating its underlying mechanism. The results showed that leptin significantly promoted U87 tumor cells growth in a time-and-dose-dependent manner. Leptin increased cell DNA synthesis and promoted G(0)/G(1) phase to S phase transition, but without any influence on cell apoptosis. In addition, leptin treatment resulted in phosphorylation of Signal Transducers and Activators of Transcription 3 (STAT3) on Tyr705, the key transcription factor in Janus-Activated Kinase (JAK)/STAT3 signaling pathway. All the data suggest that the JAK/STAT3 signaling pathway may be involved in promoting U87 glioblastoma growth mediated by leptin, which may be a target for anti-neoplastic treatments for glioblastoma.

Process Evaluation of a Lifestyle Intervention in Primary Care

The Groningen Overweight and Lifestyle (GOAL) intervention effectively prevents weight gain. The present study describes a process evaluation in which 214 participants in the intervention group received a structured questionnaire within 7 months (a median of 5 months) after the end of the intervention. The authors investigated the content of the intervention (on basis of the participants’ recall), the participants’ satisfaction of the intervention, the participants’ satisfaction with the nurse practitioners (NPs), and the determinants of the participants’ satisfaction. In general, the results show that the content corresponded well with the protocol for the intervention, except for the number of telephone calls and the percentage of participants with individualized goals for a healthy lifestyle. The overall satisfaction of the participants was high, and success and perceived success and a low educational level were important determinants for a higher overall satisfaction grade. Furthermore, the NP was considered to be an expert and motivational to learning and keeping up a healthy lifestyle. The authors therefore conclude that the GOAL study is feasible and indicates that the NP is well equipped to treat these patients. However, it is recommended to reinforce the advice given and the lifestyle goals after the first contact sessions.

The association between shift work and unhealthy weight: a cross-sectional analysis from the Nurses and Midwives' e-cohort Study

OBJECTIVE

To examine the association between shift work and unhealthy weight among female nurses and midwives.

METHODS

A cross-sectional study. Measurement outcomes included shift work, unhealthy weight (underweight: body mass index [BMI] < 18.5; overweight: BMI 25.0 to 29.9; obesity: BMI > 30.0), diet quality, physical-activity level, alcohol consumption, and smoking status.

RESULTS

Among the 2494 participants (1259 day and 1235 shift workers), only 1% of the participants were underweight, 31.8% were overweight, and 26.9% were obese. After adjusting the selected confounders, shift workers were 1.15 times more likely to be overweight/obese than day workers (P = 0.013, 95% confidence interval, 1.03 to 1.28; P = 0.02, 95% confidence interval, 1.02 to 1.30, respectively).

CONCLUSIONS

Shift work is associated with higher risk of being overweight/obese. Longitudinal studies are being undertaken to better understand the causal relationship between shift work and unhealthy weight.

Leptin activates STAT3 and ERK1/2 pathways and induces endometrial cancer cell proliferation

Obesity is an established risk factor for endometrial cancer. Leptin, a secreted protein of the ob gene by white adipose tissue, plays an important role in the regulation of food intake and energy consumption in the brain and acts as a potential growth stimulator in normal and neoplastic cancer cells. However, a direct role for leptin in endometrial cancer has not been demonstrated. In the present study, the effect of leptin on the proliferation of Ishikawa endometrial cancer cells was investigated as well as the possible mechanism(s) underlying this action in endometrial cancers which express both short and long isoforms of leptin receptors. The expression of leptin receptor (ObRb) in Ishikawa cells was detected by RT-PCR and Western blotting. The cells after serum starvation, were treated by leptin with various concentrations (0, 10, 50, 100, 150 ng/mL) for different durations (6, 12, 24 h). The effect of leptin treatment on cell proliferation was examined by MTT assay. Meanwhile, inhibitory effect of Janus tyrosine kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) inhibitor AG490 or extracellular signal-regulated kinase 1/2 (ERK1/2) inhibitor PD98059 on the proliferation of Ishikawa cells induced by leptin was also studied. Ishikawa cells were treated with 100 ng/mL leptin for various periods (0, 20, 40, 60 min), and the levels of STAT3 phosphorylation and ERK1/2 phosphorylation were examined by Western blotting. The results showed that leptin induced the phosphorylation of STAT3 and the activation of ERK1/2 in a time- and dose-dependent manner in the Ishikawa endometrial cancer cells. Blocking STAT3 phosphorylation with the inhibitor AG490, or blocking ERK1/2 activation by the specific ERK1/2 kinase inhibitor, PD98059, abolished leptin-induced proliferation of Ishikawa cells. In addition, leptin was found to potently induce the invasion of endometrial cancer cells in a Matrigel invasion assay. Leptin-stimulated invasion was effectively blocked by pharmacological inhibitors of STAT3 (AG490) and ERK1/2 kinase (PD98059). These results suggested that leptin promotes endometrial cancer growth and invasiveness by activating STAT3 and ERK1/2 signaling pathways and therefore blocking its action at the receptor level can be a rational therapeutic strategy.