Nutrition, metabolic factors and cancer risk

Mixed Treatments Comparison of Oral Nutrition Interventions for Blood Immune Cell Parameters in Cancer Patients: Systematic Review and Network Meta-Analysis

Oral nutrition interventions are commonly applied as an assistant therapeutic approach, which could affect the balance of the immunological response but with mixed evidence. The objective of this study is to identify the potential of different oral nutrition interventions for blood immune cell parameters in cancer patients. Randomized controlled trials, which were published in peer-reviewed journals in the language of English, and which identified the effects of different oral nutrition interventions on cancer patients, were screened and included in the databases of PubMed, Medline, Embase, and Web of Science. White blood cell count (WBC), lymphocyte count, CD4/CD8, and neutrophil count were selected as outcome measures. For the result, 11 trials were included. The agreement between authors reached a kappa value of 0.78. Beta-carotene supplementation has a high potential in inducing a positive effect on blood immune cell parameters for cancer patients (first positive for WBC and CD4/CD8, second positive for lymphocyte count), as well as a combination of physical exercise and hypocaloric healthy eating intervention (first positive for lymphocyte and neutrophil count, second positive for WBC). Oral nutrition supplementations with a single substance have less potential to provide a positive effect on blood immune cell parameters for cancer patients (glutamine: 0.30 and 0.28 to be the last selection for WBCs and lymphocytes; Omega 3: 0.37 to be the last selection for WBCs; Protein: 0.44 to be the last selection for lymphocytes; Zinc: 0.60 to be the last selection for neutrophils). In conclusion, the programs of immunonutrition therapy for different cancer patients might be different. The past perception that mixed oral nutritional supplementations are superior to oral nutritional supplements with a single substance might be wrong and the selection of oral nutritional supplementation need cautiousness. A combination of physical exercise might have a positive effect but also needs a higher level of evidence. Registration Number: CRD42021286396.

Evaluation of blood pressure in pediatric survivors of acute lymphoblastic leukemia and healthy children; A case-control study

Background:

The exact prevalence of hypertension in children surviving acute lymphoblastic leukemia (ALL) has not been fully estimated. The aim of this study was to investigate the prevalence of arterial hypertension (AH) and to determine the risk factors for the development of AH in children surviving ALL with current treatments.

Materials and Methods:

A total of 150 patients (84 males, 66 females, with an age range of 1–16 years) were included in the study. Demographic and clinical information of patients were initially recorded. Hypertension is defined as average systolic blood pressure (BP) and/or diastolic BP that is greater than the 95^th percentile for gender, age, and height.

Results:

The mean age at the assessment of BP was 11.3 and 9.8 years in the ALL and control group, respectively. A total of 20.6% of survivors of ALL and 10% of controls had high BP. Most patients in both groups had normal BP (65.3% patients in ALL group and 75.4% subjects in the control group). The number of patients with hypertension was significantly higher in ALL patients as compared with the control group (P = 0.026).

Conclusion:

The prevalence of AH in children surviving ALL is higher than in children in the general population, which emphasizes the need for regular monitoring of BP in children surviving ALL and intervention in the lifestyle of this population. Careful follow-up of BP status is warranted for long-term survivors of childhood cancer.

Breast Cancer Primary Prevention and Diet: An Umbrella Review

Introduction: Many studies have been published, but none have pooled the useful evidence available in the literature to produce guidelines and health policies promoting healthy eating styles to prevent breast cancer (BC). The present study aimed to summarize the evidence produced to date, taking a judicious, critical approach to the quality of the studies analyzed. Methods: An umbrella review method was adopted, which is a systematic review of second-level studies, meta-analyses and literature reviews. Results: In all, 48 studies were considered: 32 meta-analyses, 4 pooled analyses, 5 systematic reviews, and 7 qualitative reviews. A higher intake of total meat, or red or processed meats, or foods with a high glycemic index, or eggs would seem to be associated with a higher risk of BC. Some foods, such as vegetables, would seem instead to have an inverse association with BC risk. One meta-analysis revealed an inverse association between citrus fruit and mushroom consumption and BC. Some nutrients, such as calcium, folate, vitamin D, lignans and carotenoids, also seem to be inversely associated with BC risk. The evidence is still conflicting as concerns exposure to other dietary elements (e.g., polyunsaturated fatty acids, dairy foods). Conclusion: Nutrition is one of the most modifiable aspects of people's lifestyles and dietary choices can affect health and the risk of cancer. Overall, adhering to a healthy eating style may be associated with a significant reduction in the risk of BC.

Regulation of pancreatic cancer TRAIL resistance by protein O-GlcNAcylation

TRAIL-activating therapy is promising in treating various cancers, including pancreatic cancer, a highly malignant neoplasm with poor prognosis. However, many pancreatic cancer cells are resistant to TRAIL-induced apoptosis despite their expression of intact death receptors (DRs). Protein O-GlcNAcylation is a versatile posttranslational modification that regulates various biological processes. Elevated protein O-GlcNAcylation has been recently linked to cancer cell growth and survival. In this study, we evaluated the role of protein O-GlcNAcylation in pancreatic cancer TRAIL resistance, and identified higher levels of O-GlcNAcylation in TRAIL-resistant pancreatic cancer cells. With gain- and loss-of-function of the O-GlcNAc-adding enzyme, O-GlcNActransferase (OGT), we determined that increasing O-GlcNAcylation rendered TRAIL-sensitive cells more resistant to TRA-8-induced apoptosis, while inhibiting O-GlcNAcylation promoted TRA-8-induced apoptosis in TRAIL-resistance cells. Furthermore, we demonstrated that OGT knockdown sensitized TRAIL-resistant cells to TRA-8 therapy in a mouse model in vivo. Mechanistic studies revealed direct O-GlcNAc modifications of DR5, which regulated TRA-8-induced DR5 oligomerization. We further defined that DR5 O-GlcNAcylation was independent of FADD, the adapter protein for the downstream death-inducing signaling. These studies have demonstrated an important role of protein O-GlcNAcylation in regulating TRAIL resistance of pancreatic cancer cells; and uncovered the contribution of O-GlcNAcylation to DR5 oligomerization and thus mediating DR-inducing signaling.

Dietary compounds and cutaneous malignant melanoma: recent advances from a biological perspective

Cutaneous malignant melanoma is a heterogeneous disease, being the consequence of specific genetic alterations along several molecular pathways. Despite the increased knowledge about the biology and pathogenesis of melanoma, the incidence has grown markedly worldwide, making it extremely important to develop preventive measures. The beneficial role of correct nutrition and of some natural dietary compounds in preventing malignant melanoma has been widely demonstrated. This led to numerous studies investigating the role of several dietary attitudes, patterns, and supplements in the prevention of melanoma, and ongoing research investigates their impact in the clinical management and outcomes of patients diagnosed with the disease. This article is an overview of recent scientific advances regarding specific dietary compounds and their impact on melanoma development and treatment.

Suppressed OGT expression inhibits cell proliferation and modulates EGFR expression in renal cell carcinoma

Purpose

O-linked N-acetylglucosamine (O-GlcNAc or O-GlcNAcylation) is a post-translational modification, which plays a vital role in the progression of various cancers. The purpose of the present study was to assess O-GlcNAcylation in human renal cell carcinoma (RCC).

Methods

O-GlcNAcylation levels and O-GlcNAc-transferase (OGT) expression in human RCC cell lines and 10 paired clinical tissues were detected by Western blot and Immunohistochemis-try. Then, the effects of O-GlcNAcylation on RCC cell proliferation in vitro were investigated by Cell Counting Kit-8 assay. A xenograft assay was performed to assess the in vivo effects of OGT knockdown in RCC cells. Cell apoptosis and cell cycle assays were performed by flow cytometry. Co-immunoprecipitation assays were used to assess epidermal growth factor receptor (EGFR) O-GlcNAcylation and the interaction between OGT and EGFR.

Results

O-GlcNAcylation levels and OGT expression were increased in RCC, and the high amounts correlated with poor patient prognosis. OGT knockdown significantly suppressed RCC cell proliferation in vitro and in vivo. Notably, EGFR was modulated by O-GlcNAcylation and directly interacted with OGT.

Conclusion

These findings provide novel insights into the oncogenic roles of O-GlcNAcylation and OGT in the development of RCC, indicating that OGT might be used as a target for RCC therapy in the future.

Suppressed OGT expression inhibits cell proliferation while inducing cell apoptosis in bladder cancer

Background

This study aimed to explore hyper-O-linked N-acetylglucosaminylation (O-GlcNAcylation) with an elevation of the expression of O-linked-β-N-acetylglucosamine transferase (OGT) in human bladder cancer.

Methods

Immunohistochemical staining for OGT and O-GlcNAcylation was performed in 20 paired human bladder cancer and adjacent normal tissues, as well as in human bladder cancer tissue microarrays (N = 169). The expression level of OGT and O-GlcNAcylation in cell lines were detected using the Western blot analysis. The effects of O-GlcNAcylation on the cell proliferation of bladder cancer were detected using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and clone formation assays. Cell apoptosis and cell cycle analysis were detected using flow cytometry. The autophagy of bladder cancer cells was investigated using the Western blot analysis, and GFP–LC3 plasmid was used to detect the autophagic flux. MTT assay was performed to detect the sensitivity of bladder cancer cells to cisplatin after OGT knockdown.

Results

The expression of OGT and the O-GlcNAcylation were upregulated in bladder cancer tissues and cell lines. O-GlcNAcylation and OGT were observed in nucleus and cytoplasm and found to be higher in muscle-invasive bladder cancer (MIBC) than in non-muscle-invasive bladder cancer (NMIBC). Reducing hyper-O-GlcNAcylation by OGT knockdown inhibited the proliferation of bladder cancer cells in vitro and xenograft tumor growth in vivo, triggered apoptosis, as well as led to cell cycle arrest. It also increased autophagy in bladder cancer cells. This study demonstrated increased autophagy pro-survival, but not pro-death. Reducing hyper-O-GlcNAcylation by OGT knockdown facilitated the chemosensitivity of bladder cancer cells to cis-platinum.

Conclusions

The data indicated that hyper-O-GlcNAcylation enhanced oncogenic phenotypes and was involved in DNA damage response in bladder cancer.

Hypothalamic AMPK and energy balance

AMP-activated protein kinase (AMPK) is the main cellular energy sensor. Activated following a depletion of cellular energy stores, AMPK will restore the energy homoeostasis by increasing energy production and limiting energy waste. At a central level, the AMPK pathway will integrate peripheral signals (mostly hormones and metabolites) through neuronal networks. Hypothalamic AMPK is directly implicated in feeding behaviour, brown adipose tissue (BAT) thermogenesis and browning of white adipose tissue (WAT). It also participates in other metabolic functions: glucose and muscle metabolisms, as well as hepatic function. Numerous anti-obesity and/or antidiabetic agents, such as nicotine, metformin and liraglutide, are known to induce their effects through a modulation of AMPK pathway, either at central or at peripheral levels. Moreover, the weight-gaining side effects of antipsychotic drugs, such as olanzapine, are also mediated by hypothalamic AMPK. Therefore, considering hypothalamic AMPK as a therapeutic target in metabolic diseases appears as an interesting strategy due to its implication in feeding and energy expenditure, the two sides of the energy balance equation.

The roles of PPARs in human diseases

Peroxisome proliferator-activated receptors (PPARs), as members of nuclear hormone receptor superfamily, can be activated by binding natural or synthetic ligands. The use of related ligands has revealed many potential roles for PPARs in the pathogenesis of some human metabolic disorders and inflammatory-related disease. Based on the previous studies, this review primarily concluded the current progress of knowledge regarding the specific biological activity of PPARs in cancers, atherosclerosis, and type 2 diabetes mellitus, providing a foundation for the potential therapeutic use of PPAR ligands in human diseases.

O-Linked N-Acetylglucosamine Transiently Elevates in HeLa Cells during Mitosis

O-linked N-acetylglucosamine (O-GlcNAc) is a dynamic post-translational modification of serine and threonine residues on nuclear and cytoplasmic proteins. O-GlcNAc modification influences many cellular mechanisms, including carbohydrate metabolism, signal transduction and protein degradation. Multiple studies also showed that cell cycle might be modulated by O-GlcNAc. Although the role of O-GlcNAc in the regulation of some cell cycle processes such as mitotic spindle organization or histone phosphorylation is well established, the general behaviour of O-GlcNAc regulation during cell cycle is still controversial. In this study, we analysed the dynamic changes of overall O-GlcNAc levels in HeLa cells using double thymidine block. O-GlcNAc levels in G₁, S, G₂ and M phase were measured. We observed that O-GlcNAc levels are significantly increased during mitosis in comparison to the other cell cycle phases. However, this change could only be detected when mitotic cells were enriched by harvesting round shaped cells from the G₂/M fraction of the synchronized cells. Our data verify that O-GlcNAc is elevated during mitosis, but also emphasize that O-GlcNAc levels can significantly change in a short period of time. Thus, selection and collection of cells at specific cell-cycle checkpoints is a challenging, but necessary requirement for O-GlcNAc studies.

EJE PRIZE 2017: Hypothalamic AMPK: a golden target against obesity?

AMP-activated protein kinase (AMPK) is a cellular gauge that is activated under conditions, such as low energy, increasing energy production and reducing energy waste. Centrally, the AMPK pathway is a canonical route regulating energy homeostasis, by integrating peripheral signals, such as hormones and metabolites, with neuronal networks. Current evidence links hypothalamic AMPK with feeding, brown adipose tissue (BAT) thermogenesis and browning of white adipose tissue (WAT), as well as muscle metabolism, hepatic function and glucose homeostasis. The relevance of these data is interesting from a therapeutic point of view as several agents with potential anti-obesity and/or antidiabetic effects, some currently in clinical use, such as nicotine, metformin and liraglutide are known to act through AMPK, either peripherally or centrally. Furthermore, the orexigenic and weight-gaining effects of the worldwide use of antipsychotic drugs (APDs), such as olanzapine, are also mediated by hypothalamic AMPK. Overall, this evidence makes hypothalamic AMPK signaling an interesting target for the drug development, with its potential for controlling both sides of the energy balance equation, namely feeding and energy expenditure through defined metabolic pathways.

Preventive Healthcare: A Neural Network Analysis of Behavioral Habits and Chronic Diseases

The research aims to explore the association between behavioral habits and chronic diseases, and to identify a portfolio of risk factors for preventive healthcare. The data is taken from the Behavioral Risk Factor Surveillance System (BRFSS) database of the Centers for Disease Control and Prevention, for the year 2012. Using SPSS Modeler, we deploy neural networks to identify strong positive and negative associations between certain chronic diseases and behavioral habits. The data for 475,687 records from BRFS database included behavioral habit variables of consumption of soda and fruits/vegetables, alcohol, smoking, weekly working hours, and exercise; chronic disease variables of heart attack, stroke, asthma, and diabetes; and demographic variables of marital status, income, and age. Our findings indicate that with chronic conditions, behavioral habits of physical activity and fruit and vegetable consumption are negatively associated; soda, alcohol, and smoking are positively associated; and income and age are positively associated. We contribute to individual and national preventive healthcare by offering a portfolio of significant behavioral risk factors that enable individuals to make lifestyle changes and governments to frame campaigns and policies countering chronic conditions and promoting public health.

Physical Activity Protects the Human Brain against Metabolic Stress Induced by a Postprandial and Chronic Inflammation

In recent years, it has become clear that chronic systemic low-grade inflammation is at the root of many, if not all, typically Western diseases associated with the metabolic syndrome. While much focus has been given to sedentary lifestyle as a cause of chronic inflammation, it is less often appreciated that chronic inflammation may also promote a sedentary lifestyle, which in turn causes chronic inflammation. Given that even minor increases in chronic inflammation reduce brain volume in otherwise healthy individuals, the bidirectional relationship between inflammation and sedentary behaviour may explain why humans have lost brain volume in the last 30,000 years and also intelligence in the last 30 years. We review evidence that lack of physical activity induces chronic low-grade inflammation and, consequently, an energy conflict between the selfish immune system and the selfish brain. Although the notion that increased physical activity would improve health in the modern world is widespread, here we provide a novel perspective on this truism by providing evidence that recovery of normal human behaviour, such as spontaneous physical activity, would calm proinflammatory activity, thereby allocating more energy to the brain and other organs, and by doing so would improve human health.

Higher body mass index may be a predictor of extrathyroidal extension in patients with papillary thyroid microcarcinoma

Recently, higher body mass index (BMI) has been associated with aggressive pathologic features of papillary thyroid carcinoma. The aim of this study was to clarify the relationship between BMI and aggressive pathologic features of papillary thyroid microcarcinoma (PTMC) and to evaluate whether the BMI can be a prognostic factor of PTMC. This retrospective study included 612 PTMC patients who underwent surgical excision at a referral center between April 2006 and December 2007. Patients were grouped according to BMI (<25 or ≥25 kg/m2). Multivariable logistic regression analysis was performed to determine independent predictors of aggressive pathologic features (advanced stage, extrathyroidal extension, and lymph node metastasis), with adjustment for age, gender, tumor size, multifocality, thyroid stimulating hormone (TSH) level, and BMI (value/group). PTMC patients with a BMI≥25 kg/m2 showed significantly higher prevalences of extrathyroidal extension, advanced pathologic TNM stage, and male gender, compared to those of patients with a BMI<25 kg/m2. Lymph node metastasis and mean TSH level were not significantly different between the two BMI subgroups. In multivariable analysis, the BMI≥25 kg/m2 group was positively associated with the presence of extrathyroidal extension (adjusted odds ratio 1.49, P=0.05). Higher BMI was associated with extrathyroidal extension in PTMC patients. This study suggests that the BMI could be considered as a prognostic factor for predicting the presence of extrathyroidal extension and it may help decide the appropriate surgical extent for PTMC patients.

A survey of etiologic hypotheses among testicular cancer researchers

Basic research results can provide new ideas and hypotheses to be examined in epidemiological studies. We conducted a survey among testicular cancer researchers on hypotheses concerning the etiology of this malignancy. All researchers on the mailing list of Copenhagen Testis Cancer Workshops and corresponding authors of PubMed-indexed articles identified by the search term 'testicular cancer' and published within 10 years (in total 2750 recipients) were invited to respond to an e-mail-based survey. Participants of the 8th Copenhagen Testis Cancer Workshop in May 2014 were subsequently asked to rate the plausibility of the suggested etiologic hypotheses on a scale of 1 (very implausible) to 10 (very plausible). This report describes the methodology of the survey, the score distributions by individual hypotheses, hypothesis group, and the participants' major research fields, and discuss the hypotheses that scored as most plausible. We also present plans for improving the survey that may be repeated at a next international meeting of experts in testicular cancer. Overall 52 of 99 (53%) registered participants of the 8th Copenhagen Testis Cancer Workshop submitted the plausibility rating form. Fourteen of 27 hypotheses were related to exposures during pregnancy. Hypotheses with the highest mean plausibility ratings were either related to pre-natal exposures or exposures that might have an effect during pregnancy and in post-natal life. The results of the survey may be helpful for triggering more specific etiologic hypotheses that include factors related to endocrine disruption, DNA damage, inflammation, and nutrition during pregnancy. The survey results may stimulate a multidisciplinary discussion about new etiologic hypotheses of testicular cancer.

Cross-sectional associations of acylation stimulating protein (ASP) and adipose tissue gene expression with estradiol and progesterone in pre- and postmenopausal women

OBJECTIVE

Sex steroid hormones play an important regulatory role in fat metabolism and obesity. We hypothesized involvement of interactions between ovarian hormones with acylation stimulating protein (ASP).

DESIGN, PATIENTS AND MEASUREMENTS

In 392 women with wide age (18-69 years) and body size (BMI: 17 to 90 kg/m(2) ) ranges, fasting plasma levels of ASP, ovarian hormones, glucose, adiponectin and lipids/apolipoproteins were assessed, along with determination of metabolic syndrome (MS) features. Gene expression of C3 (ASP precursor) and related receptors C5L2, C3aR and C5aR in subcutaneous and omental adipose tissues was measured in a subset.

RESULTS

Acylation stimulating protein correlated negatively with concentrations of estradiol (P < 0·0001), adiponectin (P < 0·001) and apolipoprotein A1 (P < 0·001) and positively with apolipoprotein B levels (P < 0·001), systolic blood pressure (P < 0·001), waist circumference (P < 0·001), and triglyceride concentrations (P < 0·01). In age-matched groups of lean, overweight, metabolically healthy obese (MHO) and obese with metabolic syndrome (MSO), there was a stepwise increase in ASP levels (P < 0·001) while concentrations of adiponectin (P < 0·0001) and estradiol (P < 0·001) but not those of progesterone decreased. Progesterone but not estradiol levels correlated positively with C3 gene expression in omental adipose tissue (P < 0·05) and negatively with C5L2 expression in both omental (P < 0·01) and subcutaneous (P < 0·05) adipose tissues.

CONCLUSION

Our results are consistent with the concept that sex hormones differentially influence circulating ASP and adipose tissue gene expression of its related proteins in a depot-specific manner. ASP may play a role in the regulation of regional fat metabolism through interactions with sex hormones in women.

Potential chemoprevention activity of pterostilbene by enhancing the detoxifying enzymes in the HT-29 cell line

Detoxifying enzymes are present in most epithelial cells of the human gastrointestinal tract where they protect against xenobiotics which may cause cancer. Induction of examples such as glutathione S-transferase (GST) and its thiol conjugate, glutathione (GSH) as well as NAD(P)H: quinoneoxidoreductase (NQO1) facilitate the excretion of carcinogens and thus preventing colon carcinogenesis. Pterostilbene, an analogue of resveratrol, has demonstrated numerous pharmacological activities linked with chemoprevention. This study was conducted to investigate the potential of pterostilbene as a chemopreventive agent using the HT-29 colon cancer cell line to study the modulation of GST and NQO1 activities as well as the GSH level. Initially, our group, established the optimum dose of 24 hours pterostilbene treatment using MTT assays. Then, effects of pterostilbene (0-50 μM) on GST and NQO1 activity and GSH levels were determined using GST, NQO1 and Ellman assays, respectively. MTT assay of pterostilbene (0-100 μM) showed no cytotoxicity toward the HT-29 cell line. Treatment increased GST activity in the cell line significantly (p<0.05) at 12.5 and 25.0 μM. In addition, treatment at 50 μM increased the GSH level significantly (p<0.05). Pterostilbene also enhanced NQO1 activity significantly (p<0.05) at 12.5 μM and 50 μM. Hence, pterostilbene is a potential chemopreventive agent capable of modulation of detoxifiying enzyme levels in HT-29 cells.

[Protein O-GlcNAcylation and regulation of cell signalling: involvement in pathophysiology]

O-GlcNAcylation corresponds to the addition of N-acetyl glucosamine (GlcNAc) on serine or threonine residues of cytosolic and nuclear proteins. This reversible post-translational modification regulates protein phosphorylation, sub-cellular localisation, stability and activity. Only two enzymes, OGT (O-linked N-acetyl-glucosaminyltransferase) and OGA (O-linked N-acetyl-β-D glucosaminidase), control the addition and removal of GlcNAc from more than a thousand of proteins. Alternative splicing generates different isoforms of OGT and OGA, and address these enzymes to different sub-cellular compartments (mitochondria, cytosol...), restraining their action to specific subsets of substrates. Moreover, interaction with adaptor proteins may also help address these enzymes to specific substrates. Alterations in protein O-GlcNAcylation have been observed in a number of important human diseases, such as Alzheimer, cancer and diabetes. A reciprocal relationship between Tau protein phosphorylation and O-GlcNAcylation has been observed, and decreased O-GlcNAcylation in the brain of patients with Alzheimer diseases may favour Tau aggregation, destabilisation of microtubules and neuronal alterations. Alterations in OGT/OGA expression levels, and in protein O-GlcNAcylation, have been described in different types of cancer, and much evidence indicates that O-GlcNAcylation may participate in abnormal proliferation and migration of cancer cells. O-GlcNAcylation of transcription factors and signalling effectors may also participate in defects observed in diabetes. Indeed, in situation of chronic hyperglycaemia, abnormal O-GlcNAcylation may have deleterious effect on insulin secretion and action, resulting in further impairment of glucose homeostasis. Therefore, O-GlcNAcylation appears to be a major regulator of cellular activities and may play an important part in different human diseases. However, because of the large spectrum of OGT and OGA substrates, targeting O-GlcNAc for treatment of these diseases will be a highly challenging task.

Small molecule adenosine 5'-monophosphate activated protein kinase (AMPK) modulators and human diseases

Adenosine 5'-monophosphate activated protein kinase (AMPK) is a master sensor of cellular energy status that plays a key role in the regulation of whole-body energy homeostasis. AMPK is a serine/threonine kinase that is activated by upstream kinases LKB1, CaMKKβ, and Tak1, among others. AMPK exists as αβγ trimeric complexes that are allosterically regulated by AMP, ADP, and ATP. Dysregulation of AMPK has been implicated in a number of metabolic diseases including type 2 diabetes mellitus and obesity. Recent studies have associated roles of AMPK with the development of cancer and neurological disorders, making it a potential therapeutic target to treat human diseases. This review focuses on the structure and function of AMPK, its role in human diseases, and its direct substrates and provides a brief synopsis of key AMPK modulators and their relevance in human diseases.

Body size, physical activity, early-life energy restriction, and associations with methylated insulin-like growth factor-binding protein genes in colorectal cancer

BACKGROUND

We investigated body size, physical activity, and early-life energy restriction in relation to colorectal tumors with and without methylated insulin-like growth factor-binding protein (IGFBP) genes, which are putative tumor-suppressor genes.

METHODS

We determined IGFBP2, IGFBP3, and IGFBP7 promoter CpG island hypermethylation in tumors of 733 colorectal cancer cases from the Netherlands Cohort Study (N = 120,852). Participants self-reported lifestyle and dietary factors at baseline in 1986. Using a case-cohort approach (N subcohort = 5,000), we estimated hazard ratios (HR) for colorectal cancer by extent of IGFBP methylation.

RESULTS

Comparison of the highest versus lowest sex-specific tertiles of adult body mass index (BMI) gave multivariable-adjusted HRs [95% confidence intervals (CI)] for colorectal cancers with 0 (18.7%), 1 (29.5%), 2 (32.4%), and 3 (19.5%) methylated genes of 1.39 (0.88-2.19), 1.11 (0.77-1.62), 1.67 (1.17-2.38), and 2.07 (1.29-3.33), respectively. Other anthropometric measures and physical activity were not associated with colorectal cancer risk by extent of IGFBP methylation, except height in sex-specific analyses for women. Exposure to energy restriction during the Dutch Hunger Winter versus nonexposure gave HRs (95% CIs) for colorectal cancers with 0, 1, 2, and 3 methylated genes of 1.01 (0.67-1.53), 1.03 (0.74-1.44), 0.72 (0.52-0.99), and 0.50 (0.32-0.78), respectively.

CONCLUSIONS

Adult BMI, height (in women only), and early-life energy restriction were associated with the risk of having a colorectal tumor characterized by IGFBP methylation.

IMPACT

Body size may particularly increase the risk of IGFBP gene-methylated colorectal tumors; this finding might facilitate more targeted approaches to prevent obesity-related colorectal cancers.

Dash of faith: a faith-based participatory research pilot study

The Dash of Faith pilot used a community-based participatory research approach to design an experiential dietary intervention based on two African-American churches, one intervention and one comparison. Congregation members identified components that were incorporated into 12 weekly and 4 monthly sessions, with a goal of increasing fruit and vegetable and lowering fat intake. At 2 months, a marginally significant (p = 0.07) increase in fruit and vegetable consumption was observed in the intervention group but was not maintained at study conclusion. We propose that these mixed findings may be attributable, in part, to bias introduced by the participatory nature of the design.

O-GlcNAcylation stabilizes β-catenin through direct competition with phosphorylation at threonine 41

Dysfunctions in Wnt signaling increase β-catenin stability and are associated with cancers, including colorectal cancer. In addition, β-catenin degradation is decreased by nutrient-dependent O-GlcNAcylation. Human colon tumors and colons from mice fed high-carbohydrate diets exhibited higher amounts of β-catenin and O-GlcNAc relative to healthy tissues and mice fed a standard diet, respectively. Administration of the O-GlcNAcase inhibitor thiamet G to mice also increased colonic expression of β-catenin. By ETD-MS/MS, we identified 4 O-GlcNAcylation sites at the N terminus of β-catenin (S23/T40/T41/T112). Furthermore, mutation of serine and threonine residues within the D box of β-catenin reduced O-GlcNAcylation by 75%. Interestingly, elevating O-GlcNAcylation in human colon cell lines drastically reduced phosphorylation at T41, a key residue of the D box responsible for β-catenin stability. Analyses of β-catenin O-GlcNAcylation mutants reinforced T41 as the most crucial residue that controls the β-catenin degradation rate. Finally, inhibiting O-GlcNAcylation decreased the β-catenin/α-catenin interaction necessary for mucosa integrity, whereas O-GlcNAcase silencing improved this interaction. These results suggest that O-GlcNAcylation regulates not only the stability of β-catenin, but also affects its localization at the level of adherens junctions. Accordingly, we propose that O-GlcNAcylation of β-catenin is a missing link between the glucose metabolism deregulation observed in metabolic disorders and the development of cancer.

Physical activity, sex steroid, and growth factor concentrations in pre- and post-menopausal women: a cross-sectional study within the EPIC cohort

PURPOSE

Increased physical activity (PA) is associated with a reduced risk of several cancers. PA may reduce cancer risk by changing endogenous hormones levels, but relatively little research has focused on this topic. The purpose of this study was to elucidate the relation between PA and endogenous hormone concentrations.

METHODS

A cross-sectional analysis of 798 pre- and 1,360 post-menopausal women included as controls in case-control studies on endogenous hormones (steroids, progesterone, sex-hormone-binding globulin (SHBG), and growth factors) levels, and cancer risk nested within European Prospective Investigation into Cancer and Nutrition cohort was performed. Multivariate regression analyses were performed to compare geometric mean levels of hormones and SHBG by categories of PA.

RESULTS

In pre-menopausal women, active women had 19 % significantly lower concentrations of androstenedione, 14 % lower testosterone, and 20 % lower free testosterone than inactive women, while no differences were observed for estrogens, progesterone, SHBG, and growth factors. In post-menopausal women, active women had 18 % significantly lower estradiol and 20 % lower free estradiol concentrations than inactive women, while no differences were observed for the other hormones and SHBG. More vigorous forms of physical activity were associated with higher insulin-like growth factor-I concentrations. Adjustment for body mass index did not alter the associations. Overall, the percentage of variance in hormone concentrations explained by PA levels was <2 %.

CONCLUSIONS

Our results support the hypothesis of an influence, although small in magnitude, of PA on sex hormone levels in blood, independent of body size.

A review on the role of L-carnitine in the management of tamoxifen side effects in treated women with breast cancer

L-carnitine is an antioxidant and is found to be a protective agent against many diseases including cancer. This review illustrates the possible role of L-carnitine as an add-on therapy to breast cancer patients maintained on tamoxifen. The objectives of carnitine treatment are diverse: improving tamoxifen-related side effects, offering better cancer prognosis by reducing the risk of developing cancer recurrence or metastasis, and modulating the growth factors which may be, in part, a prospective illustration to overcome tamoxifen resistance. So, it could be recommended to supplement L-carnitine to breast cancer patients starting tamoxifen treatment.

O-GlcNAcylation-inducing treatments inhibit estrogen receptor α expression and confer resistance to 4-OH-tamoxifen in human breast cancer-derived MCF-7 cells

O-GlcNAcylation (addition of N-acetyl-glucosamine on serine or threonine residues) is a post-translational modification that regulates stability, activity or localization of cytosolic and nuclear proteins. O-linked N-acetylgluocosmaine transferase (OGT) uses UDP-GlcNAc, produced in the hexosamine biosynthetic pathway to O-GlcNacylate proteins. Removal of O-GlcNAc from proteins is catalyzed by the β-N-Acetylglucosaminidase (OGA). Recent evidences suggest that O-GlcNAcylation may affect the growth of cancer cells. However, the consequences of O-GlcNAcylation on anti-cancer therapy have not been evaluated. In this work, we studied the effects of O-GlcNAcylation on tamoxifen-induced cell death in the breast cancer-derived MCF-7 cells. Treatments that increase O-GlcNAcylation (PUGNAc and/or glucosoamine) protected MCF-7 cells from death induced by tamoxifen. In contrast, inhibition of OGT expression by siRNA potentiated the effect of tamoxifen on cell death. Since the PI-3 kinase/Akt pathway is a major regulator of cell survival, we used BRET to evaluate the effect of PUGNAc+glucosamine on PIP₃ production. We observed that these treatments stimulated PIP₃ production in MCF-7 cells. This effect was associated with an increase in Akt phosphorylation. However, the PI-3 kinase inhibitor LY294002, which abolished the effect of PUGNAc+glucosamine on Akt phosphorylation, did not impair the protective effects of PUGNAc+glucosamine against tamoxifen-induced cell death. These results suggest that the protective effects of O-GlcNAcylation are independent of the PI-3 kinase/Akt pathway. As tamoxifen sensitivity depends on the estrogen receptor (ERα) expression level, we evaluated the effect of PUGNAc+glucosamine on the expression of this receptor. We observed that O-GlcNAcylation-inducing treatment significantly reduced the expression of ERα mRNA and protein, suggesting a potential mechanism for the decreased tamoxifen sensitivity induced by these treatments. Therefore, our results suggest that inhibition of O-GlcNAcylation may constitute an interesting approach to improve the sensitivity of breast cancer to anti-estrogen therapy.

Lipid profile among Moroccan overweight women and breast cancer: a case-control study

BACKGROUND

Breast cancer has become the most common type of cancer in Morocco. In 2005, 127 new cases in women, representing 33.5% of female cancers, were added to the National Center of Oncology registry. The incidence of breast cancer is higher in Morocco than in the three other Maghreb countries, and it is significantly lower than in Western countries where it stands at over 80 cases per 100,000 people.

PURPOSE

This 2-year long case-control study was conducted to assess the causal relationship between the lipid profile of overweight Moroccan women and breast cancer risk.

PATIENTS AND METHODS

Overweight female patients with breast cancer (n = 400) were compared to 400 healthy controls at the National Institute of Oncology of Rabat. The epidemiological data on the disease and physical activity were gathered by interviewing the patients who had their lipid profile measured (total cholesterol, triglycerides, high density lipoprotein cholesterol, and low density lipoprotein cholesterol). Body mass index was used to determine if patients were overweight.

RESULTS

Univariate analysis revealed a significant association between breast cancer and high body mass index (odds ratio [OR] = 1.31; 95% confidence interval [CI] = 1.25-1.37), menopause (OR = 2.68; 95% CI = 2-3.55), lack of physical activity (OR = 0.26; 95% CI = 0.21-0.31), and triglyceridemia (OR = 3.78; 95% CI = 2.73-5.23). Multivariate analysis revealed that the statistically significant increase in breast cancer risk was associated with a higher body mass index (OR = 1.11; 95% CI = 1.04-1.18), menopause (OR = 9.11; 95% CI = 4.76-17.47), and high triglyceride levels (OR = 4.5; 95% CI = 2.94-6.88). However, a protective effect for physical activity was detected (OR = 0.35; 95% CI = 0.26-0.48).

CONCLUSION

This study suggests that there is a connection between hypertriglyceridemia, obesity, and breast cancer risk and confirms a protective role for physical activity on breast cancer risk.

Hormonal, metabolic, and inflammatory profiles and endometrial cancer risk within the EPIC cohort--a factor analysis

A "Western" lifestyle characterized by physical inactivity and excess weight is associated with a number of metabolic and hormonal dysregulations, including increased circulating estrogen levels, hyperinsulinemia, hyperglycemia, and chronic inflammation. The same hormonal and metabolic axes might mediate the association between this lifestyle and the development of endometrial cancer. Using data collected within the European Prospective Investigation into Cancer and Nutrition (EPIC), a prospective cohort study carried out in 10 European countries during 1992-2000, we conducted a factor analysis to delineate important components that summarize the variation explained by a set of biomarkers and to examine their association with endometrial cancer risk. Prediagnostic levels of testosterone, androstenedione, dehydroepiandrosterone sulfate, sex hormone-binding globulin, estrone, estradiol, C-peptide, insulin-like growth factor-binding proteins 1 and 2, adiponectin, high- and low-density lipoprotein cholesterol, glucose, triglycerides, tumor necrosis factor (TNF) α, soluble TNF receptors 1 and 2, C-reactive protein, interleukin-6, and interleukin-1 receptor antagonist were measured in 233 incident endometrial cancer cases and 446 matched controls. Factor analysis identified 3 components associated with postmenopausal endometrial cancer risk that could be labeled "insulin resistance/metabolic syndrome," "steroids," and "inflammation" factors. A fourth component, "lipids," was not significantly associated with endometrial cancer. In conclusion, besides the well-known associations of risk with sex hormones and insulin-regulated physiological axes, our data further support the hypothesis that inflammation factors play a role in endometrial carcinogenesis.

Associations between body mass index and clinico-pathological characteristics of papillary thyroid cancer

OBJECTIVE

Epidemiological studies have demonstrated that excess weight increases the risk of thyroid cancer. However, the associations between excess weight and prognostic factors for thyroid cancer are uncertain. We evaluated the relationships between body mass index (BMI) and clinico-pathological features and outcomes of papillary thyroid cancer (PTC).

PATIENTS AND METHODS

Retrospective analysis of 2057 patients with PTC was performed. Patients were grouped according to BMI (underweight, normal weight, overweight and obesity)-based World Health Organization standardized categories. Logistic regression models were used to assess the relationships between BMI and clinico-pathological features of PTC. A Cox proportional hazards model was used to examine the association between BMI and disease recurrence.

RESULTS

A 5-kg/m(2) increase in BMI was associated with PTC tumours larger than 1 cm [odds ratio (OR) 1.31, P < 0.001], with microscopic extrathyroidal invasion (OR 1.23, P = 0.006), and with advanced tumour-node-metastasis (TNM) stage (OR, 1.30, P = 0.003), which is independent of confounding variables such as gender, age, serum TSH, total cholesterol and fasting glucose level. The multivariate-adjusted OR [95% confidence intervals (CI)] in the overweight (25.0-29.9 kg/m(2)) and obese (BMI ≥ 30) groups for tumours larger than 1 cm were 1.41 (1.10-1.81) and 2.17 (1.23-3.82), respectively, compared to the normal weight group (BMI 18.5-24.9). The multivariate-adjusted OR (95% CI) for microscopic extrathyroidal extension in the obesity group was 1.88 (1.06-3.32), and the OR for advanced TNM stage in the overweight group was 1.35 (1.02-1.79) compared to the normal weight group. During follow-up (median, 84 month; range, 1-185), 43 patients (2.1%) experienced recurrence. There were no significant differences in recurrence of PTCs among BMI groups.

CONCLUSIONS

Higher BMI was strongly associated with larger tumour size, extrathyroidal invasion and advanced TNM stage of PTCs. However, there was no difference in recurrence rate among BMI groups. This study suggests that excess weight is associated with aggressive features of PTCs. Further studies with long-term follow-up are needed to confirm this finding.

O-GlcNAcylation: A New Cancer Hallmark?

O-linked N-acetylglucosaminylation (O-GlcNAcylation) is a reversible post-translational modification consisting in the addition of a sugar moiety to serine/threonine residues of cytosolic or nuclear proteins. Catalyzed by O-GlcNAc-transferase (OGT) and removed by O-GlcNAcase, this dynamic modification is dependent on environmental glucose concentration. O-GlcNAcylation regulates the activities of a wide panel of proteins involved in almost all aspects of cell biology. As a nutrient sensor, O-GlcNAcylation can relay the effects of excessive nutritional intake, an important cancer risk factor, on protein activities and cellular functions. Indeed, O-GlcNAcylation has been shown to play a significant role in cancer development through different mechanisms. O-GlcNAcylation and OGT levels are increased in different cancers (breast, prostate, colon…) and vary during cell cycle progression. Modulating their expression or activity can alter cancer cell proliferation and/or invasion. Interestingly, major oncogenic factors have been shown to be directly O-GlcNAcylated (p53, MYC, NFκB, β-catenin…). Furthermore, chromatin dynamics is modulated by O-GlcNAc. DNA methylation enzymes of the Tet family, involved epigenetic alterations associated with cancer, were recently found to interact with and target OGT to multi-molecular chromatin-remodeling complexes. Consistently, histones are subjected to O-GlcNAc modifications which regulate their function. Increasing number of evidences point out the central involvement of O-GlcNAcylation in tumorigenesis, justifying the attention received as a potential new approach for cancer treatment. However, comprehension of the underlying mechanism remains at its beginnings. Future challenge will be to address directly the role of O-GlcNAc-modified residues in oncogenic-related proteins to eventually propose novel strategies to alter cancer development and/or progression.

Critical review: vegetables and fruit in the prevention of chronic diseases

BACKGROUND

Vegetables and fruit provide a significant part of human nutrition, as they are important sources of nutrients, dietary fibre, and phytochemicals. However, it is uncertain whether the risk of certain chronic diseases can be reduced by increased consumption of vegetables or fruit by the general public, and what strength of evidence has to be allocated to such an association.

METHODS

Therefore, a comprehensive analysis of the studies available in the literature and the respective study results has been performed and evaluated regarding obesity, type 2 diabetes mellitus, hypertension, coronary heart disease (CHD), stroke, cancer, chronic inflammatory bowel disease (IBD), rheumatoid arthritis (RA), chronic obstructive pulmonary disease (COPD), asthma, osteoporosis, eye diseases, and dementia. For judgement, the strength of evidence for a risk association, the level of evidence, and the number of studies were considered, the quality of the studies and their estimated relevance based on study design and size.

RESULTS

For hypertension, CHD, and stroke, there is convincing evidence that increasing the consumption of vegetables and fruit reduces the risk of disease. There is probable evidence that the risk of cancer in general is inversely associated with the consumption of vegetables and fruit. In addition, there is possible evidence that an increased consumption of vegetables and fruit may prevent body weight gain. As overweight is the most important risk factor for type 2 diabetes mellitus, an increased consumption of vegetables and fruit therefore might indirectly reduces the incidence of type 2 diabetes mellitus. Independent of overweight, there is probable evidence that there is no influence of increased consumption on the risk of type 2 diabetes mellitus. There is possible evidence that increasing the consumption of vegetables and fruit lowers the risk of certain eye diseases, dementia and the risk of osteoporosis. Likewise, current data on asthma, COPD, and RA indicate that an increase in vegetable and fruit consumption may contribute to the prevention of these diseases. For IBD, glaucoma, and diabetic retinopathy, there was insufficient evidence regarding an association with the consumption of vegetables and fruit.

CONCLUSIONS

This critical review on the associations between the intake of vegetables and fruit and the risk of several chronic diseases shows that a high daily intake of these foods promotes health. Therefore, from a scientific point of view, national campaigns to increase vegetable and fruit consumption are justified. The promotion of vegetable and fruit consumption by nutrition and health policies is a preferable strategy to decrease the burden of several chronic diseases in Western societies.

IGF-1 deficiency in combination with a low basic hBD-2 and hBD-3 gene expression might counteract malignant transformation in pleomorphic adenomas in vitro

This study investigated the IGF-1-influence on oncological relevant genes in pleomorphic adenomas. Therefore A64-tumor cells were stimulated by recombinant IGF-1. After RNA-extraction, transcript levels of hBD-1, hBD-2, hBD-3, DEFA1/3, DEFA4, S100A4, Psoriasin, DOC-1, EGF, EGFR, and IGFR were analyzed by qRT-PCR at t = 0, 4, 8, 24, 48, and 72 hr. The gene-products were visualized by immunostaining. A64-tumor-cells were deficient for hBD-1 and IGF-1. IGF-1 downregulates hBD-2 and hBD-3 without influencing hBD-1-expression. IGF-1 only slightly affects DEFA1/3-, DEFA4-, S100A4-, Psoriasin-, DOC-1-, EGF-, EGFR-, and IGFR-gene-expression. IGF-1-deficiency combined with low basic hBD-2-gene-expression and hBD-3-gene-expression might counteract, whereas hBD-1-deficiency promotes malignant transformation in pleomorphic adenomas.

Physical activity, energy restriction, and the risk of pancreatic cancer: a prospective study in the Netherlands

BACKGROUND

Because of their influence on insulin concentrations, we hypothesized that both physical activity and energy restriction may reduce the risk of pancreatic cancer.

OBJECTIVE

We examined the associations between physical activity, proxies for energy restriction, and pancreatic cancer risk.

DESIGN

The Netherlands Cohort Study consisted of 120,852 individuals who completed a baseline questionnaire in 1986. After 13.3 y of follow-up, 408 cases were available for analysis. Self-reported information on physical activity was collected. Three indicators were used as proxies for energy restriction: father's employment status during the Economic Depression (1932-1940) and place of residence during the World War II years (1940-1944) and the Hunger winter (1944-1945).

RESULTS

For past sports activities, we observed a significantly decreased risk of pancreatic cancer (HR: 0.80; 95% CI: 0.64, 0.99). Proxies for energy restriction were not related to pancreatic cancer risk. When the results for energy restriction were stratified by height, a significant multiplicative interaction was observed for the Economic Depression period (P = 0.002). Shorter individuals (height less than the sex-specific median adult height) with an unemployed father during the Economic Depression period had a significantly lower cancer risk (HR: 0.31; 95% CI: 0.14, 0.66) than did taller individuals with an employed father. No significant interactions were observed for exposure to energy restriction during the World War II years and the Hunger winter.

CONCLUSIONS

Our results suggest a modestly decreased risk of pancreatic cancer associated with past sports activity. With respect to proxies for energy restriction, our findings suggest that shorter individuals exposed to energy restriction during adolescence may have a reduced risk, whereas taller individuals may not.

Clinical and nutritional status of surgical patients with and without malignant diseases: cross-sectional study

CONTEXT

Malnutrition is frequently observed in inpatients with malignant diseases and may contribute to longer hospital stays.

OBJECTIVE

To compare the nutritional status, lymphocyte count, hemoglobin values and length of hospital stay of patients with and without malignant diseases.

METHODS

This comparative study assessed indicators of nutritional status, namely body mass index, recent weight loss, lymphocyte count, hemoglobin and length of hospital stay, of 928 surgical patients with and without malignant diseases (50.2% females and 49.8% males). The chi-square test was used to compare proportions and the Mann-Whitney test was used to compare continuous measurements between two groups. The significance level was set at 5%.

RESULTS

Patients with malignant diseases had longer hospital stays (P<0.0001), furthermore, a higher percentage of patients with malignant diseases had body mass index <18.5 (P<0.0001) and experienced recent weight changes (P<0.0002). Lymphocyte count also differed statistically between the groups (P = 0.0131), which lower levels were identified among patients with malignant diseases.

CONCLUSION

The lymphocyte count, hemoglobin values and weight loss are important findings of nutritional depletion in patients with malignant diseases.

The burden of cancer risk in Canada's indigenous population: a comparative study of known risks in a Canadian region

BACKGROUND

Canadian First Nations, the largest of the Aboriginal groups in Canada, have had lower cancer incidence and mortality rates than non-Aboriginal populations in the past. This pattern is changing with increased life expectancy, a growing population, and a poor social environment that influences risk behaviors, metabolic conditions, and disparities in screening uptake. These factors alone do not fully explain differences in cancer risk between populations, as genetic susceptibility and environmental factors also have significant influence. However, genetics and environment are difficult to modify. This study compared modifiable behavioral risk factors and metabolic-associated conditions for men and women, and cancer screening practices of women, between First Nations living on-reserve and a non-First Nations Manitoba rural population (Canada).

METHODS

The study used data from the Canadian Community Health Survey and the Manitoba First Nations Regional Longitudinal Health Survey to examine smoking, binge drinking, metabolic conditions, physical activity, fruit/vegetable consumption, and cancer-screening practices.

RESULTS

First Nations on-reserve had significantly higher rates of smoking (P < 0.001), binge drinking (P < 0.001), obesity (P < 0.001) and diabetes (P < 0.001), and less leisure-time physical activity (P = 0.029), and consumption of fruits and vegetables (P < 0.001). Sex differences were also apparent. In addition, First Nations women reported significantly less uptake of mammography screening (P < 0.001) but similar rates for cervical cancer screening.

CONCLUSIONS

Based on the findings of this retrospective study, the future cancer burden is expected to be high in the First Nations on-reserve population. Interventions, utilizing existing and new health and social authorities, and long-term institutional partnerships, are required to combat cancer risk disparities, while governments address economic disparities.

Metabolic syndrome and pancreatic cancer risk: a case-control study in Italy and meta-analysis

We assessed the relation between metabolic syndrome (MetS), its components, and pancreatic cancer risk in an Italian case-control study and performed a meta-analysis of epidemiological studies published up to February 2011. The case-control study included 326 patients with incident pancreatic cancer and 652 controls admitted to the same hospitals for acute, non-neoplastic conditions. MetS was defined as having at least 3 conditions among diabetes, drug-treated hypertension, hyperlipidemia, and body mass index at least 25 kg/m(2) at age 30 years. We computed multivariate odds ratios (ORs) and the corresponding 95% confidence intervals (CIs) from logistic regression models adjusted for tobacco smoking, education, and other sociodemographic variables. For the meta-analysis, we calculated summary relative risks (RRs) using random-effects models. The OR of pancreatic cancer in the case-control study was 2.36 (95% CI, 1.43-3.90) for diabetes, 0.77 (95% CI, 0.55-1.08) for hypertension, 1.38 (95% CI, 0.94-2.01) for hypercholesterolemia, and 1.27 (95% CI, 0.91-1.78) for being overweight at age 30 years. The risk was significantly increased for subjects with 3 or more MetS components (OR = 2.13, 95% CI 1.01-4.49) compared with subjects with no component, the estimates being consistent among strata of sex, age, and alcohol consumption. The meta-analysis included 3 cohort studies and our case-control study, and found a summary RR of 1.55 (95% CI, 1.19-2.01) for subjects with MetS. Metabolic syndrome is related to pancreatic cancer risk. Diabetes is the key component related to risk.

AMP-activated protein kinase modulators: a patent review (2006 - 2010)

INTRODUCTION

AMPK is a key player in the regulation of energy balance at both the cellular and whole-body levels, placing it at the center stage in studies of metabolic disorders. Recently, AMPK has also been identified as a potential target for either therapy or prevention of some types of cancer. Thus, identification of AMPK modulators for possible use as novel therapeutic drugs, both for treatment of metabolic disorders and cancer, will have a high commercial potential.

AREAS COVERED

This review covers the structures and activities of AMPK modulators described in the patent literature since 2006. The patents reviewed include those for direct and/or indirect activators of AMPK, and novel pharmaceutical compounds with potential for use in the prevention and/or treatment of metabolic disorders, and cancer targeting AMPK.

EXPERT OPINION

Targeting of AMPK appears to be an attractive strategy in the treatment of metabolic disorders. However, some detrimental effects of AMPK have also been reported, including a possible tumor-promoting effect in some settings and a heart disease-causing effect. Moreover, activation of AMPK in the hypothalamus may cause undesired consequences, such as an increase in feeding and body weight gain. These effects, therefore, must be carefully assessed for the development of therapeutic drugs targeting AMPK.

Dietary fiber, carbohydrates, glycemic index, and glycemic load in relation to breast cancer prognosis in the HEAL cohort

BACKGROUND

Dietary intake of fiber, carbohydrate, glycemic index (GI), and glycemic load (GL) may influence breast cancer survival, but consistent and convincing evidence is lacking.

METHODS

We investigated associations of dietary fiber, carbohydrates, GI, and GL with breast cancer prognosis among n = 688 stage 0 to IIIA breast cancer survivors in the Health, Eating, Activity, and Lifestyle (HEAL) study. Premenopausal and postmenopausal women from Western Washington State, Los Angeles County, and New Mexico participated. Usual diet was assessed with a food frequency questionnaire. Total mortality, breast cancer mortality, nonfatal recurrence, and second occurrence data were obtained from SEER (Surveillance, Epidemiology, and End Results) registries and medical records. Cox proportional hazards regression estimated multivariate-adjusted hazard ratios and 95% confidence intervals (CI).

RESULTS

During a median of 6.7 years follow-up after diagnosis, n = 106 total deaths, n = 83 breast cancer-specific deaths, and n = 82 nonfatal recurrences were confirmed. We observed an inverse association between fiber intake and mortality. Multivariate-adjusted hazard rate ratios (HRR) comparing high to low intake were 0.53 (95% CI 0.23-1.23) and 0.75 (95% CI 0.43-1.31). A threshold effect was observed whereby no additional benefit was observed for intakes of 9 g/d or more. Fiber intake was suggestively inversely associated with breast cancer-specific mortality (HRR = 0.68, 95% CI 0.27-1.70) and risk of nonfatal recurrence or second occurrence (HRR = 0.68, 95% CI 0.27-1.70), but results were not statistically significant.

CONCLUSION

Dietary fiber was associated with a nonsignificant inverse association with breast cancer events and total mortality. Further studies to assess and confirm this relationship are needed in order to offer effective dietary strategies for breast cancer patients.

IMPACT

Increasing dietary fiber may an effective lifestyle modification strategy for breast cancer survivors.

Metabolic factors and the risk of pancreatic cancer: a prospective analysis of almost 580,000 men and women in the Metabolic Syndrome and Cancer Project

BACKGROUND

The aim of this study was to investigate the association between factors in metabolic syndrome (MetS; single and combined) and the risk of pancreatic cancer.

METHODS

The Metabolic Syndrome and Cancer Project is a pooled cohort containing data on body mass index, blood pressure, and blood levels of glucose, cholesterol, and triglycerides. During follow-up, 862 individuals were diagnosed with pancreatic cancer. Cox proportional hazards analysis was used to calculate relative risks (RR) with 95% confidence intervals using the above-mentioned factors categorized into quintiles and transformed into z-scores. All z-scores were summarized and a second z-transformation creating a composite z-score for MetS was done. All risk estimates were calibrated to correct for a regression dilution bias.

RESULTS

The trend over quintiles was positively associated with the risk of pancreatic cancer for mid-blood pressure (mid-BP) and glucose in men and for body mass index, mid-BP, and glucose in women. The z-score for the adjusted mid-BP (RR, 1.10; 1.01-1.20) and the calibrated z-score for glucose (RR, 1.37; 1.14-1.34) were positively associated with pancreatic cancer in men. In women, a positive association was found for calibrated z-scores for mid-BP (RR, 1.34; 1.08-1.66), for the calibrated z-score for glucose (RR, 1.98; 1.41-2.76), and for the composite z-score for MetS (RR, 1.58; 1.34-1.87).

CONCLUSION

Our study adds further evidence to a possible link between abnormal glucose metabolism and risk of pancreatic cancer.

IMPACT

To our knowledge, this is the first study on MetS and pancreatic cancer using prediagnostic measurements of the examined factors.

Insulin resistance and lower plasma adiponectin increase malignancy risk in nondiabetic continuous ambulatory peritoneal dialysis patients

End-stage renal disease patients have a higher risk for developing cancer. Although several causes for this increased risk have been proposed, the risk factors for cancer development in this population have not been elucidated. The aim of this study was to determine whether metabolic derangements, including insulin resistance and altered adipokines, increase the risk of developing malignancies in peritoneal dialysis (PD) patients, who are vulnerable to metabolic disorders because of excessive glucose absorbed from the dialysate. Study subjects comprised 106 nondiabetic PD patients who had been on PD for a minimum of 3 months with no overt malignancy. Baseline anthropometry, fasting glucose, insulin, and adiponectin were measured. The development of malignancy was evaluated during the follow-up period. During the mean follow-up of 47.0 ± 23.7 months, malignancy occurred in 15 patients (14.2%). The most common site of cancer was the kidney (26.7%), followed by thyroid (13.3%) and stomach (13.3%). Baseline insulin levels and homeostasis model assessment of insulin resistance were significantly higher, whereas plasma adiponectin levels were significantly lower, in patients who developed malignancy. Cox proportional hazards analysis revealed that insulin levels, homeostasis model assessment of insulin resistance, and lower adiponectin were independent predictors of malignancy. These findings demonstrate that insulin resistance and lower adiponectin levels could be risk factors for malignancy in nondiabetic PD patients.

A strong genetic association between the tumor necrosis factor locus and proliferative vitreoretinopathy: the retina 4 project

OBJECTIVE

To assess the genetic contribution to proliferative vitreoretinopathy (PVR) and report the strong association observed in the tumor necrosis factor (TNF) locus.

DESIGN

As a component of The Retina 4 Project, a case-controlled, candidate gene association study in the TNF locus was conducted.

PARTICIPANTS AND CONTROLS

Blood from 450 patients with (138 cases) and without (312 controls) post-rhegmatogenous retinal detachment (RD) PVR was genotyped to determine polymorphisms located in the TNFα gene.

METHODS

Single nucleotide polymorphisms (SNPs) with correlation coefficients of ≥ 0.8 and a minor allelic frequency of ≥ 10% were studied. Functional SNPs or SNPs previously described in association with other inflammatory diseases were also added for analysis. The SNPlex Genotyping System (Applied Biosystems, Foster City, CA) was used for genotyping. Single nucleotide polymorphism and haplotype analyses were performed. Bioinformatic tools were used to evaluate those SNPs that were significantly associated.

MAIN OUTCOME MEASURES

Single and haplotypic significant associations with PVR.

RESULTS

A total of 11 common tag SNPs in the following genes were analyzed: lymphotoxin alpha (LTA), TNFα, leukocyte-specific transcript 1 (LST1), and the activating natural killer receptor p30 (NCR3). After permutation, there was a significant association in the non-synonymous polymorphism rs2229094(T→C) in the LTA gene (P = 0.0283), which encodes a cysteine to arginine change in the signal peptide. This marker was also present in all significant haplotypic associations and was not observed in any nonsignificant associations. When this SNP was analyzed using bioinformatic tools, the hydropathy profile changed, as well as the transmembrane region and the splicing site predictions.

CONCLUSIONS

The strong association found in the rs2229094(T→C) of the LTA gene may indicate an important role of this polymorphism in the development of PVR. If supported in extended studies, the rs2229094(T→C) may have significant implications regarding the genetic risk of the retinal repairing process.

[Effect of lifestyle counseling given by health personnel on the changes in dietary habits of Hungarian women treated for cancer]

The aim of this study was to investigate the changes in dietary habits in women with gynecological or breast cancer, and to analyze the role of some demographic factors, type of the malignant tumor, and the role of medical staff's advice in dietary behavior change of these women, after the diagnosis of cancer. A self-administered questionnaire-based retrospective study was performed, and 155 randomly selected patients, treated for gynecological or breast cancer, were involved. A self-developed questionnaire was used to measure the socio-demographic characteristics, the circumstances of visiting the physician, therapy, present health status and lifestyle before and after the diagnosis of neoplasm. More than three-fourths of the women reported changes in nutrition after the diagnosis of cancer. The consumption of fruits and vegetables increased in the highest proportion (70.3%). Women with higher education changed their diet in higher proportion (p=0.031) compared to women with lower education. Women who were advised to change their lifestyle by their therapists were about four times more likely (OR: 3.87; CI: 1.40-10.69 ) to change their nutrition. Patients with breast cancer changed three times more likely (OR: 3.21; CI: 1.05-9.84) their dietary habits than patients with gynecological cancer. The most influential proven factor to make cancer patients alter their diet was being advised for this by physicians. Thus, our study proved that physicians and nurses have a very important role in changing their cancer patients' nutritional habits into a healthier one.

Lifestyle, anthropometric, and obesity-related physiologic determinants of insulin-like growth factor-1 in the Third National Health and Nutrition Examination Survey (1988-1994)

PURPOSE

Epidemiologic studies suggest that insulin-like growth factor-1 (IGF-1) is associated with obesity and, more recently, cancer. This study investigates multiple lifestyle, physiologic, and anthropometric determinants of circulating IGF-1 concentrations.

METHODS

Nationally representative data were used from the cross-sectional Third National Health and Nutrition Examination (NHANES III, 1988-1994) survey, which measured IGF-1 concentrations in blood, from a subsample of participants who were examined in the morning. After exclusion of persons with missing data, 6,058 men and women 20 years of age or older were included in the study.

RESULTS

The mean IGF-1 concentrations were 260 ng/mL in the entire population and were higher among men as compared with women (278.8 vs. 241.3 ng/mL; p<0.0001). IGF-1 decreased with increasing age (p<0.0001), body mass index (p<0.0001), and waist circumference (p<0.0001). Individuals with metabolic syndrome had lower IGF-1 concentrations after adjustment for covariates (p=0.0008). IGF-1 was inversely associated with increasing number of metabolic syndrome abnormalities (p=0.0008). All associations were stronger among women compared with men except across concentrations of glucose. IGF-1 concentrations did not vary by any other lifestyle or physiologic factors.

CONCLUSIONS

Age, adiposity, hyperglycemia, and metabolic syndrome influenced circulating IGF-1 concentrations. Diet and physical activity had no impact on IGF-1 in this nationally representative population.

Physical activity and hematologic cancer prevention

This chapter presents the epidemiologic evidence on the association between physical activity and hematologic cancers and related hypothesized biologic mechanisms. Some preliminary indications of a protective role for physical activity for non-Hodgkin's lymphoma, leukemia, multiple myeloma, and Hodgkin's lymphoma exist, but the level of epidemiologic evidence is still insufficient to make any definitive conclusions regarding the nature of these associations. Several plausible biologic mechanisms underlying the possible associations between physical activity and hematologic cancers have been proposed, including enhancement of immune function, reduction in obesity, improvement of antioxidant defense systems, impact on metabolic hormones, and anti-inflammatory effects. Future studies should improve the estimation of physical activity by using more reliable, valid, and comprehensive measurement tools, assessing all components of physical activity (type, intensity, and time period), and conducting intervention studies to evaluate the effect of physical activity on various biomarkers of cancer in order to provide further insight into plausible biologic mechanisms underlying the possible association between physical activity and hematologic cancers.

Blood glucose and risk of incident and fatal cancer in the metabolic syndrome and cancer project (me-can): analysis of six prospective cohorts

BACKGROUND

Prospective studies have indicated that elevated blood glucose levels may be linked with increased cancer risk, but the strength of the association is unclear. We examined the association between blood glucose and cancer risk in a prospective study of six European cohorts.

METHODS AND FINDINGS

The Metabolic syndrome and Cancer project (Me-Can) includes cohorts from Norway, Austria, and Sweden; the current study included 274,126 men and 275,818 women. Mean age at baseline was 44.8 years and mean follow-up time was 10.4 years. Excluding the first year of follow-up, 18,621 men and 11,664 women were diagnosed with cancer, and 6,973 men and 3,088 women died of cancer. We used Cox regression models to calculate relative risk (RR) for glucose levels, and included adjustment for body mass index (BMI) and smoking status in the analyses. RRs were corrected for regression dilution ratio of glucose. RR (95% confidence interval) per 1 mmol/l increment of glucose for overall incident cancer was 1.05 (1.01-1.10) in men and 1.11 (1.05-1.16) in women, and corresponding RRs for fatal cancer were 1.15 (1.07-1.22) and 1.21 (1.11-1.33), respectively. Significant increases in risk among men were found for incident and fatal cancer of the liver, gallbladder, and respiratory tract, for incident thyroid cancer and multiple myeloma, and for fatal rectal cancer. In women, significant associations were found for incident and fatal cancer of the pancreas, for incident urinary bladder cancer, and for fatal cancer of the uterine corpus, cervix uteri, and stomach.

CONCLUSIONS

Data from our study indicate that abnormal glucose metabolism, independent of BMI, is associated with an increased risk of cancer overall and at several cancer sites. Our data showed stronger associations among women than among men, and for fatal cancer compared to incident cancer. Please see later in the article for the Editors' Summary.