Περίληψη:
Previous studies have shown inconsistent associations of folate intake
and polymorphisms of the methylenetetrahydrofolate reductase (MTHFR)
gene with gastric cancer risk. Our nested case-control study within the
European Prospective Investigation into Cancer and Nutrition cohort is
the first prospective study of blood folate levels and gastric cancer.
Gastric cancer cases (n = 247) and controls (n = 631) were matched for
study center, age, sex, and time of blood donation. Two common single
nucleotide polymorphisms of the MTHFR gene were determined, as were
plasma concentrations of folate, cobalamin (vitamin B12), total
homocysteine, and methylmalonic acid (cobalamin deficiency marker) in
prediagnostic plasma. Risk measures were calculated with conditional
logistic regression. Although no relations were observed between plasma
folate or total homocysteine concentrations and gastric cancer, we
observed a trend toward lower risk of gastric cancer with increasing
cobalamin concentrations (odds ratio, 0.79 per SD increase in cobalamin;
P = 0.01). Further analyses showed that the inverse association between
cobalamin and gastric cancer was confined to cancer cases with low
pepsinogen A levels (marker of severe chronic atrophic gastritis) at the
time of blood sampling. The 677 C -> T MTHFR polymorphism was not
associated with gastric cancer, but we observed an increased risk with
the variant genotype of the 1298 A -> C polymorphism (odds ratio, 1.47
for CC versus AA; P = 0.04). In conclusion, we found no evidence of a
role of folate in gastric cancer etiology. However, we observed
increased gastric cancer risk at low cobalamin levels that was most
likely due to compromised cobalamin status in atrophic gastritis
preceding gastric cancer.
Συγγραφείς:
Vollset, Stein Emil
Igland, Jannicke
Jenab, Mazda and
Fredriksen, Ase
Meyer, Klaus
Eussen, Simone
Gjessing, Hakon
K.
Ueland, Per Magne
Pera, Guillem
Sala, Nuria
Agudo,
Antonio
Capella, Gabriel
Del Giudice, Giuseppe
Palli,
Domenico
Boeing, Heiner
Weikert, Cornelia
Bueno-de-Mesquita,
H. Bas
Carneiro, Fatima
Pala, Valeria
Vineis, Paolo and
Tumino, Rosario
Panico, Salvatore
Berglund, Goran
Manjer,
Jonas
Stenling, Roger
Hallmans, Goran
Martinez, Carmen and
Dorronsoro, Miren
Barricarte, Aurelio
Navarro, Carmen and
Quiros, Jose R.
Allen, Naomi
Key, Timothy J.
Bingham, Sheila
and Linseisen, Jakob
Kaaks, Rudolf
Overvad, Kim
Tjonneland,
Anne
Buchner, Frederike L.
Peeters, Petra H. M.
Numans,
Mattijs E.
Clavel-Chapelon, Francoise
Boutron-Ruault,
Marie-Christine
Trichopoulou, Antonia
Lund, Eiliv
Slimani,
Nadia
Ferrari, Pietro
Riboli, Elio
Gonzalez, Carlos A.
