Dietary intake of branched-chain amino acids and pancreatic cancer risk in a case-control study from Italy

Circulating branched-chain amino acids (BCAAs), a subgroup of the nine essential amino acids, have been associated to pancreatic cancer risk. The aim of this study is to estimate the relation between BCAA intake from diet and pancreatic cancer risk.We analysed data from a multicentric Italian case-control study, including 326 pancreatic cancer cases and 652 controls, matched to cases by study centre, sex and age. A validated food-frequency questionnaire was used to collect the participants' usual diet before cancer diagnosis (or hospital admission for controls) and to compute dietary intakes of various nutrients, including BCAAs. Odds ratios (ORs) and corresponding confidence intervals (CIs) were computed through logistic regression models conditioned on the matching variables and adjusted for major confounding factors, including total energy intake.We found a positive association between the BCAA intake and pancreatic cancer risk (OR for the third quartile=1.88, 95% CI=1.08-3.26; OR for the fourth quartile =2.17, 95% CI=1.17-4.06), with a significant trend in risk. The association persisted after excluding subjects with diabetes and family history of pancreatic cancer, and across strata of selected covariates.These data support and quantify the association between dietary BCAAs and pancreatic cancer, previously suggested by studies on circulating BCAAs.

Flavonoids and bladder cancer risk

PURPOSE

Flavonoids have drawn attention because of their antioxidant capacity and anti-carcinogenic effect in various types of cancer. A limited number of studies has investigated their potential effect on the risk of bladder cancer, with inconsistent results.

METHODS

We analyzed data from an Italian case-control study including 690 incident bladder cancer cases and 665 controls admitted to the same network of hospitals for acute, non-neoplastic, non tobacco-related diseases. Subjects were interviewed using a reproducible and validated food-frequency questionnaire. We applied data on food and beverage composition to estimate the intake of isoflavones, anthocyanidins, flavan-3-ols, flavanones, flavones and flavonols. We estimated odds ratios (ORs) through multiple logistic regression models, including terms for potential confounding factors, including tobacco smoking and total energy intake.

RESULTS

We found an inverse association between isoflavones (OR for the highest compared to the lowest quintile of intake = 0.56, 95% CI 0.37-0.84) and flavones (OR = 0.64, 95% CI 0.44-0.95) and bladder cancer. Non-significant inverse association was found for flavan-3-ols (OR = 0.70), flavonols (OR = 0.85) and total flavonoids (OR = 0.76). The results were consistent for non-muscle-invasive and muscle-invasive bladder cancers.

CONCLUSIONS

Our data indicate an inverse association between isoflavones and flavones with respect to bladder cancer risk.