TY - JOUR
T1 - Dietary N-nitroso compounds and risk of colorectal cancer
T2 - A case-control study in Newfoundland and Labrador and Ontario, Canada
AU - Zhu, Yun
AU - Wang, Peizhon Peter
AU - Zhao, Jing
AU - Green, Roger
AU - Sun, Zhuoyu
AU - Roebothan, Barbara
AU - Squires, Josh
AU - Buehler, Sharon
AU - Dicks, Elizabeth
AU - Zhao, Jinhui
AU - Cotterchio, Michelle
AU - Campbell, Peter T.
AU - Jain, Meera
AU - Parfrey, Patrick S.
AU - Mclaughlin, John R.
N1 - Publisher Copyright:
Copyright © The Authors 2013.
PY - 2014/3/28
Y1 - 2014/3/28
N2 - Several N-nitroso compounds (NOC) have been shown to be carcinogenic in a variety of laboratory animals, but evidence of their carcinogenicity in humans is lacking. We aimed to examine the association between NOC intake and colorectal cancer (CRC) risk and possible effect modification by vitamins C and E and protein in a large case-control study carried out in Newfoundland and Labrador and Ontario, Canada. A total of 1760 case patients with pathologically confirmed adenocarcinoma and 2481 population controls were asked to complete a self-administered FFQ to evaluate their dietary intakes 1 year before diagnosis (for cases) or interview (for controls). Adjusted OR and 95% CI were calculated across the quintiles of NOC (measured by N-nitrosodimethylamine (NDMA)) intake and relevant food items using unconditional logistic regression. NDMA intake was found to be associated with a higher risk of CRC (highest v. lowest quintiles: OR 1.42, 95% CI 1.03, 1.96; P for trend=0.005), specifically for rectal carcinoma (OR 1.61, 95% CI 1.11, 2.35; P for trend=0.01). CRC risk also increased with the consumption of NDMA-containing meats when the highest tertile was compared with the lowest tertile (OR 1.47, 95% CI 1.03, 2.10; P for trend=0.20). There was evidence of effect modification between dietary vitamin E and NDMA. Individuals with high NDMA and low vitamin E intakes had a significantly increased risk than those with both low NDMA and low vitamin E intakes (OR 3.01, 95% CI 1.43, 6.51; P for interaction=0.017). The present results support the hypothesis that NOC intake may be positively associated with CRC risk in humans. Vitamin E, which inhibits nitrosation, could modify the effect of NDMA on CRC risk.
AB - Several N-nitroso compounds (NOC) have been shown to be carcinogenic in a variety of laboratory animals, but evidence of their carcinogenicity in humans is lacking. We aimed to examine the association between NOC intake and colorectal cancer (CRC) risk and possible effect modification by vitamins C and E and protein in a large case-control study carried out in Newfoundland and Labrador and Ontario, Canada. A total of 1760 case patients with pathologically confirmed adenocarcinoma and 2481 population controls were asked to complete a self-administered FFQ to evaluate their dietary intakes 1 year before diagnosis (for cases) or interview (for controls). Adjusted OR and 95% CI were calculated across the quintiles of NOC (measured by N-nitrosodimethylamine (NDMA)) intake and relevant food items using unconditional logistic regression. NDMA intake was found to be associated with a higher risk of CRC (highest v. lowest quintiles: OR 1.42, 95% CI 1.03, 1.96; P for trend=0.005), specifically for rectal carcinoma (OR 1.61, 95% CI 1.11, 2.35; P for trend=0.01). CRC risk also increased with the consumption of NDMA-containing meats when the highest tertile was compared with the lowest tertile (OR 1.47, 95% CI 1.03, 2.10; P for trend=0.20). There was evidence of effect modification between dietary vitamin E and NDMA. Individuals with high NDMA and low vitamin E intakes had a significantly increased risk than those with both low NDMA and low vitamin E intakes (OR 3.01, 95% CI 1.43, 6.51; P for interaction=0.017). The present results support the hypothesis that NOC intake may be positively associated with CRC risk in humans. Vitamin E, which inhibits nitrosation, could modify the effect of NDMA on CRC risk.
KW - Case-control studies
KW - Colorectal cancer
KW - Effect modification
KW - N-nitroso compounds
KW - Vitamin C
KW - Vitamin E
UR - http://www.scopus.com/inward/record.url?scp=84899699633&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84899699633&partnerID=8YFLogxK
U2 - 10.1017/S0007114513003462
DO - 10.1017/S0007114513003462
M3 - Article
C2 - 24160559
AN - SCOPUS:84899699633
SN - 0007-1145
VL - 111
SP - 1109
EP - 1117
JO - British Journal of Nutrition
JF - British Journal of Nutrition
IS - 6
ER -