In this study, we aim to identify the genes responsible for colorectal cancer risk behind the loci identified in genome-wide association studies (GWAS). These genes may be candidate targets for ...developing new strategies for prevention or therapy. We analyzed the association of genotypes for 26 GWAS single nucleotide polymorphisms (SNPs) with the expression of genes within a 2 Mb region (cis-eQTLs). Affymetrix Human Genome U219 expression arrays were used to assess gene expression in two series of samples, one of healthy colonic mucosa (n = 47) and other of normal mucosa adjacent to colon cancer (n = 97, total 144). Paired tumor tissues (n = 97) were also analyzed but did not provide additional findings. Partial Pearson correlation (r), adjusted for sample type, was used for the analysis. We have found Bonferroni-significant cis-eQTLs in three loci: rs3802842 in 11q23.1 associated to C11orf53, COLCA1 (C11orf92) and COLCA2 (C11orf93; r = 0.60); rs7136702 in 12q13.12 associated to DIP2B (r = 0.63) and rs5934683 in Xp22.3 associated to SHROOM2 and GPR143 (r = 0.47). For loci in chromosomes 11 and 12, we have found other SNPs in linkage disequilibrium that are more strongly associated with the expression of the identified genes and are better functional candidates: rs7130173 for 11q23.1 (r = 0.66) and rs61927768 for 12q13.12 (r = 0.86). These SNPs are located in DNA regions that may harbor enhancers or transcription factor binding sites. The analysis of trans-eQTLs has identified additional genes in these loci that may have common regulatory mechanisms as shown by the analysis of protein-protein interaction networks.
Vitamins and essential minerals are micronutrients that are essential for the normal functioning of the human body. However, they may lead to adverse health effects if consumed in excess. The concept ...of a tolerable upper intake level (UL) is a science-based reference value, which was introduced to support policy-makers and other relevant actors in managing the risks of excess nutrient intake. EFSA's principles for establishing ULs for vitamins and minerals were originally developed by the Scientific Committee on Food in 2000. Since then, experience has been gained and the scientific field developed. This guidance from the EFSA Panel on Nutrition, Novel Foods and Food Allergens provides an updated framework to support EFSA's UL assessments. It covers aspects related to the planning of the risk assessment (problem formulation and definition of methods) and its implementation (evidence retrieval, appraisal, synthesis, integration, uncertainty analysis). As in the previous framework, the general principles developed for the risk assessment of chemicals in food are applied (hazard identification, hazard characterisation, intake assessment, risk characterisation). Peculiar to nutrients are their biochemical and physiological roles and the specific and selective mechanisms that maintain the systemic homoeostasis and body burden of the nutrient. These must be considered when conducting a risk assessment of nutrients. This document constitutes a draft guidance that will be applied in EFSA's assessments during a 1-year pilot phase and be revised and complemented as necessary. Before finalisation of the guidance, a public consultation will be launched.
Introduction
Amyloid beta (Aβ) pathology is an Alzheimer's disease early hallmark. Here we assess the value of longitudinal self‐ and informant reports of cognitive decline to predict Aβ positron ...emission tomography (PET) outcome in cognitively unimpaired middle‐aged individuals.
Methods
A total of 261 participants from the ALFA+ study underwent 18Fflutemetamol PET and Subjective Cognitive Decline Questionnaire (SCD‐Q) concurrently, and 3 years before scan. We used logistic regressions to evaluate the ability of SCD‐Q scores (self and informant) to predict Aβ PET visual read, and repeated analysis of variance to assess whether changes in SCD‐Q scores relate to Aβ status.
Results
Self‐perception of decline in memory (odds ratio OR = 1.2), and informant perception of executive decline (OR = 1.6), increased the probability of a positive scan. Informant reports 3 years before scanning predicted Aβ PET outcome. Longitudinal increase of self‐reported executive decline was predictive of Aβ in women (P = .003).
Discussion
Subjective reports of cognitive decline are useful to predict Aβ and may improve recruitment strategies.
It is unclear whether diet, and in particular certain foods or nutrients, are associated with lung cancer risk. We assessed associations of 92 dietary factors with lung cancer risk in 327 790 ...participants in the European Prospective Investigation into Cancer and Nutrition (EPIC). Cox regression yielded adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) per SD higher intake/day of each food/nutrient. Correction for multiple comparisons was performed using the false discovery rate and identified associations were evaluated in the Netherlands Cohort Study (NLCS). In EPIC, 2420 incident lung cancer cases were identified during a median of 15 years of follow‐up. Higher intakes of fibre (HR per 1 SD higher intake/day = 0.91, 95% CI 0.87‐0.96), fruit (HR = 0.91, 95% CI 0.86‐0.96) and vitamin C (HR = 0.91, 95% CI 0.86‐0.96) were associated with a lower risk of lung cancer, whereas offal (HR = 1.08, 95% CI 1.03‐1.14), retinol (HR = 1.06, 95% CI 1.03‐1.10) and beer/cider (HR = 1.04, 95% CI 1.02‐1.07) intakes were positively associated with lung cancer risk. Associations did not differ by sex and there was less evidence for associations among never smokers. None of the six associations with overall lung cancer risk identified in EPIC were replicated in the NLCS (2861 cases), however in analyses of histological subtypes, inverse associations of fruit and vitamin C with squamous cell carcinoma were replicated in the NLCS. Overall, there is little evidence that intakes of specific foods and nutrients play a major role in primary lung cancer risk, but fruit and vitamin C intakes seem to be inversely associated with squamous cell lung cancer.
What's new?
Lung cancer is the leading cause of cancer death worldwide, and while smoking is the most significant factor affecting lung cancer risk, other environmental and genetic factors may contribute. Here, the authors looked for an association between the foods people eat and their lung cancer risk. Using an approach they call a diet‐wide association study, modelled after genome‐wide association studies, they evaluated 92 individual food and nutrient intakes for association with lung cancer risk. No major associations were detected for lung cancer overall, but higher fruit and vitamin C intakes were associated with lower squamous cell lung cancer risk.
Dysregulation of transcriptional programs leads to cell malfunctioning and can have an impact in cancer development. Our study aims to characterize global differences between transcriptional ...regulatory programs of normal and tumor cells of the colon.
Affymetrix Human Genome U219 expression arrays were used to assess gene expression in 100 samples of colon tumor and their paired adjacent normal mucosa. Transcriptional networks were reconstructed using ARACNe algorithm using 1,000 bootstrap replicates consolidated into a consensus network. Networks were compared regarding topology parameters and identified well-connected clusters. Functional enrichment was performed with SIGORA method. ENCODE ChIP-Seq data curated in the hmChIP database was used for in silico validation of the most prominent transcription factors.
The normal network contained 1,177 transcription factors, 5,466 target genes and 61,226 transcriptional interactions. A large loss of transcriptional interactions in the tumor network was observed (11,585; 81% reduction), which also contained fewer transcription factors (621; 47% reduction) and target genes (2,190; 60% reduction) than the normal network. Gene silencing was not a main determinant of this loss of regulatory activity, since the average gene expression was essentially conserved. Also, 91 transcription factors increased their connectivity in the tumor network. These genes revealed a tumor-specific emergent transcriptional regulatory program with significant functional enrichment related to colorectal cancer pathway. In addition, the analysis of clusters again identified subnetworks in the tumors enriched for cancer related pathways (immune response, Wnt signaling, DNA replication, cell adherence, apoptosis, DNA repair, among others). Also multiple metabolism pathways show differential clustering between the tumor and normal network.
These findings will allow a better understanding of the transcriptional regulatory programs altered in colon cancer and could be an invaluable methodology to identify potential hubs with a relevant role in the field of cancer diagnosis, prognosis and therapy.
Glyceraldehyde‐derived advanced glycation end products (glycer‐AGEs) could contribute to colorectal cancer development and progression due to their pro‐oxidative and pro‐inflammatory properties. ...However, the association of glycer‐AGEs with mortality after colorectal cancer diagnosis has not been previously investigated. Circulating glycer‐AGEs were measured by competitive ELISA. Multivariable Cox proportional hazards models were used to calculate hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) for associations of circulating glycer‐AGEs concentrations with CRC‐specific and all‐cause mortality among 1034 colorectal cancer (CRC) cases identified within the European Prospective Investigation into Cancer and Nutrition (EPIC) study between 1993 and 2013. During a mean of 48 months of follow‐up, 529 participants died (409 from CRC). Glycer‐AGEs were statistically significantly positively associated with CRC‐specific (HRQ5 vs Q1 = 1.53, 95% CI: 1.04‐2.25, Ptrend = .002) and all‐cause (HRQ5 vs Q1 = 1.62, 95% CI: 1.16‐2.26, Ptrend < .001) mortality among individuals with CRC. There was suggestion of a stronger association between glycer‐AGEs and CRC‐specific mortality among patients with distal colon cancer (per SD increment: HRproximal colon = 1.02, 95% CI: 0.74‐1.42; HRdistal colon = 1.51, 95% CI: 1.20‐1.91; Peffect modification = .02). The highest HR was observed among CRC cases in the highest body mass index (BMI) and glycer‐AGEs category relative to lowest BMI and glycer‐AGEs category for both CRC‐specific (HR = 1.78, 95% CI: 1.02‐3.01) and all‐cause mortality (HR = 2.15, 95% CI: 1.33‐3.47), although no statistically significant effect modification was observed. Our study found that prediagnostic circulating glycer‐AGEs are positively associated with CRC‐specific and all‐cause mortality among individuals with CRC. Further investigations in other populations and stratifying by tumor location and BMI are warranted.
What's new?
Eating foods high in sugar has been associated with risk of colorectal cancer (CRC). As the body processes dietary sugars, it generates compounds called glyceraldehyde‐derived advanced glycation end products (glycer‐AGEs). Here, the authors investigated the relationship between glycer‐AGEs and CRC mortality. In an analysis of 1034 CRC cases from the EPIC cohort, they found that prediagnostic circulating glycer‐AGEs were associated with both CRC‐specific and all‐cause mortality.
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•Inheriting longer telomere length (TL) increases life expectancy.•TL is associated with Alzheimer’s disease but no other neurodegenerative diseases.•Diverse biological aging ...mechanisms might be involved in neurodegenerative diseases.
Telomere length (TL) is a biomarker of biological aging. Shorter telomeres have been associated with mortality and increased rates of age-related diseases. However, observational studies are unable to conclude whether TL is causally associated with those outcomes. Mendelian randomization (MR) was developed for assessing causality using genetic variants in epidemiological research. The objective of this study was to test the potential causal role of TL in neurodegenerative disorders and life expectancy through MR analysis. Summary level data were extracted from the most recent genome-wide association studies for TL, Alzheimer’s disease (AD), Parkinson’s disease, Frontotemporal dementia, Amyotrophic Lateral Sclerosis, Progressive Supranuclear Palsy and life expectancy. MR estimates revealed that longer telomeres inferred a protective effect on risk of AD (OR = 0.964; adjusted p-value = 0.039). Moreover, longer telomeres were significantly associated with increased life expectancy (βIVW = 0.011; adjusted p-value = 0.039). Sensitivity analyses suggested evidence for directional pleiotropy in AD analyses. Our results showed that genetically predicted longer TL may increase life expectancy and play a protective causal effect on AD. We did not observe significant causal relationships between longer TL and other neurodegenerative diseases. This suggests that the involvement of TL on specific biological mechanisms might differ between AD and life expectancy, with respect to that in other neurodegenerative diseases. Moreover, the presence of pleiotropy may reflect the complex interplay between TL homeostasis and AD pathophysiology. Further observational studies are needed to confirm these results.