Alcohol dehydrogenase and aldehyde dehydrogenase gene polymorphisms, alcohol intake and the risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition study.

BACKGROUND/OBJECTIVES: Heavy alcohol drinking is a risk factor of colorectal cancer (CRC), but little is known on the effect of polymorphisms in the alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) on the alcohol-related risk of CRC in Caucasian populations. SUBJECTS/METHODS: A nested case-control study (1269 cases matched to 2107 controls by sex, age, study centre and date of blood collection) was conducted within the European Prospective Investigation into Cancer and Nutrition (EPIC) to evaluate the impact of rs1229984 (ADH1B), rs1573496 (ADH7) and rs441 (ALDH2) polymorphisms on CRC risk. Using the wild-type variant of each polymorphism as reference category, CRC risk estimates were calculated using conditional logistic regression, with adjustment for matching factors. RESULTS: Individuals carrying one copy of the rs1229984(A) (ADH1B) allele (fast metabolizers) showed an average daily alcohol intake of 4.3 g per day lower than subjects with two copies of the rs1229984(G) allele (slow metabolizers) (P(diff)<0.01). None of the polymorphisms was associated with risk of CRC or cancers of the colon or rectum. Heavy alcohol intake was more strongly associated with CRC risk among carriers of the rs1573496(C) allele, with odds ratio equal to 2.13 (95% confidence interval: 1.26-3.59) compared with wild-type subjects with low alcohol consumption (P(interaction)=0.07). CONCLUSIONS: The rs1229984(A) (ADH1B) allele was associated with a reduction in alcohol consumption. The rs1229984 (ADH1B), rs1573496 (ADH7) and rs441 (ALDH2) polymorphisms were not associated with CRC risk overall in Western-European populations. However, the relationship between alcohol and CRC risk might be modulated by the rs1573496 (ADH7) polymorphism.

Variety in vegetable and fruit consumption and the risk of gastric and esophageal cancer in the European Prospective Investigation into Cancer and Nutrition.

Diets high in vegetables and fruits have been suggested to be inversely associated with risk of gastric cancer. However, the evidence of the effect of variety of consumption is limited. We therefore investigated whether consumption of a variety of vegetables and fruit is associated with gastric and esophageal cancer in the European Prospective Investigation into Cancer and Nutrition study. Data on food consumption and follow-up on cancer incidence were available for 452,269 participants from 10 European countries. After a mean follow-up of 8.4 years, 475 cases of gastric and esophageal adenocarcinomas (180 noncardia, 185 cardia, gastric esophageal junction and esophagus, 110 not specified) and 98 esophageal squamous cell carcinomas were observed. Diet Diversity Scores were used to quantify the variety in vegetable and fruit consumption. We used multivariable Cox proportional hazard models to calculate risk ratios. Independent from quantity of consumption, variety in the consumption of vegetables and fruit combined and of fruit consumption alone were statistically significantly inversely associated with the risk of esophageal squamous cell carcinoma (continuous hazard ratio per 2 products increment 0.88; 95% CI 0.79-0.97 and 0.76; 95% CI 0.62-0.94, respectively) with the latter particularly seen in ever smokers. Variety in vegetable and/or fruit consumption was not associated with risk of gastric and esophageal adenocarcinomas. Independent from quantity of consumption, more variety in vegetable and fruit consumption combined and in fruit consumption alone may decrease the risk of esophageal squamous cell carcinoma. However, residual confounding by lifestyle factors cannot be excluded.

Diabetes mellitus, glycated haemoglobin and C-peptide levels in relation to pancreatic cancer risk: a study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort.

AIMS/HYPOTHESIS: There has been long-standing debate about whether diabetes is a causal risk factor for pancreatic cancer or a consequence of tumour development. Prospective epidemiological studies have shown variable relationships between pancreatic cancer risk and blood markers of glucose and insulin metabolism, overall and as a function of lag times between marker measurements (blood donation) and date of tumour diagnosis. METHODS: Pre-diagnostic levels of HbA(1c) and C-peptide were measured for 466 participants with pancreatic cancer and 466 individually matched controls within the European Prospective Investigation into Cancer and Nutrition. Conditional logistic regression models were used to estimate ORs for pancreatic cancer. RESULTS: Pancreatic cancer risk gradually increased with increasing pre-diagnostic HbA(1c) levels up to an OR of 2.42 (95% CI 1.33, 4.39 highest [≥ 6.5%, 48 mmol/mol] vs lowest [≤ 5.4%, 36 mmol/mol] category), even for individuals with HbA(1c) levels within the non-diabetic range. C-peptide levels showed no significant relationship with pancreatic cancer risk, irrespective of fasting status. Analyses showed no clear trends towards increasing hyperglycaemia (as marked by HbA(1c) levels) or reduced pancreatic beta cell responsiveness (as marked by C-peptide levels) with decreasing time intervals from blood donation to cancer diagnosis. CONCLUSIONS/INTERPRETATION: Our data on HbA(1c) show that individuals who develop exocrine pancreatic cancer tend to have moderate increases in HbA(1c) levels, relatively independently of obesity and insulin resistance-the classic and major risk factors for type 2 diabetes. While there is no strong difference by lag time, more data are needed on this in order to reach a firm conclusion.