Diet, lifestyle and risk of K-ras mutation-positive and -negative colorectal adenomas.
K-ras mutation-positive (K-ras+) and -negative (K-ras-) colorectal adenomas may differ clinically and pathologically. As environmental compounds may cause mutations in the growth-related K-ras oncogene or affect clonal selection depending on mutational status, we evaluated whether the aetiology of K-ras+ and K-ras- adenomas differs. K-ras mutations in codons 12 and 13 were assessed in colorectal adenoma tissue (K-ras+: n = 81, K-ras-: n = 453). Dietary and lifestyle data were collected through questionnaires that were also administered to 709 polyp-free controls. Multiple logistic regression analyses showed that intake of vitamin B2 and monounsaturated fat were differently associated with risk of K-ras+ and K-ras- adenomas; vitamin B2 was inversely associated with K-ras- (highest vs. lowest tertile: odds ratio (OR) = 0.70, 95% confidence interval (CI) = 0.50-0.97, p trend = 0.020), but not with K-ras+ adenomas, and a positive association with monounsaturated fat was confined to K-ras- adenomas (OR = 1.57, 95% CI = 1.06-2.34, p trend = 0.029). Besides, potential, not statistically significant, differences in risk arose because red meat was distinctly positively associated with K-ras+ adenomas (OR = 1.70, 95% CI = 0.94-3.09, p trend = 0.061); total dietary and polyunsaturated fat tended to be inversely associated with risk of K-ras+ but not of K-ras- adenomas; inverse associations with dairy products, calcium, protein and tea were confined to K-ras- adenomas, and smoking was more markedly positively associated with K-ras- adenomas. No differences in risk of K-ras+ and K-ras- adenomas could be detected for other factors. In conclusion, dietary and lifestyle factors may influence risk of K-ras+ and K-ras- adenomas differently. However, epidemiological literature on diet, lifestyle and colorectal K-ras mutations is inconsistent.
Division of Human Nutrition, Wageningen University, Wageningen, The Netherlands.
Petra A
PA
Wark
Wieke
W
Van der Kuil
Janneke
J
Ploemacher
Goos N P
GN
Van Muijen
Chris J J
CJ
Mulder
Matty P
MP
Weijenberg
Frans J
FJ
Kok
Ellen
E
Kampman
D000236:Adenoma / Q000209:etiology* / Q000235:genetics; D011125:Adenomatous Polyposis Coli / Q000209:etiology; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003062:Codon; D015179:Colorectal Neoplasms / Q000209:etiology* / Q000235:genetics; D005247:Feeding Behavior; D005260:Female; D011905:Genes, ras; D006801:Humans; D008019:Life Style; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D016017:Odds Ratio; D017354:Point Mutation; D012256:Riboflavin / Q000008:administration & dosage; D018570:Risk Assessment; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects; D011795:Surveys and Questionnaires
D003062:Codon; D012256:Riboflavin