Genes coding for the glutatione S-transferase M1 (GSTM1) and Theta 1 (GSTT1) proteins are polymorphic in humans and these genes are absent, or homozygous null, in 10-60% of different ethnic populations.
These enzymes catalyze the conjugation of glutathione to numerous carcinogenic chemicals and previous epidemiologic studies have associated the null genotypes of these GST genes with higher risk of cancer.
In this study the frequency of GSTM1 and GSTT1 null genotypes was determined in Japanese patients with gastric adenocarcinoma and colorectal adenocarcinoma and compared to frequencies determined in a community-based control group.
The frequency of the null GSTM1 genotype in patients with gastric adenocarcinoma (56.8%) showed a statistically significant increase compared to the control group frequency (43.6%) (odds ratio (OR)=1.70 ; 95% CI, 1.05-2.76).
The frequency of GSTM1 null individuals was also higher among all colorectal adenocarcinoma cases, but this increase did not reach statistical significance.
After grouping by tumor site, the GSTM1 null genotype was a risk factor among the subgroup with distal colorectal tumors (61.1%) (OR=2.03 ; 95% CI, 1.06-3.90).
No consistent difference was observed between smoking patients and corresponding controls for the frequency of the GSTM1 null genotype for either cancer, although a large risk (OR=5.76 ; 95% CI 1.18-28.3) was associated with the GSTM1 null genotype in the low smoking group of gastric adenocarcinoma patients. (...)
Mots-clés Pascal : Glutathione transferase, Transferases, Enzyme, Polymorphisme, Génétique, Adénocarcinome, Côlon, Rectum, Estomac, Homme, Japonais, Prédisposition, Facteur risque, Génotype, Epidémiologie, Tumeur maligne, Estomac pathologie, Intestin pathologie, Appareil digestif pathologie, Gène GSTM1, Gène GSTT1
Mots-clés Pascal anglais : Glutathione transferase, Transferases, Enzyme, Polymorphism, Genetics, Adenocarcinoma, Colon, Rectum, Stomach, Human, Japanese, Predisposition, Risk factor, Genotype, Epidemiology, Malignant tumor, Gastric disease, Intestinal disease, Digestive diseases
Notice produite par :
Inist-CNRS - Institut de l'Information Scientifique et Technique
Cote : 96-0437392
Code Inist : 002B13B01. Création : 10/04/1997.