ABSTRACT: ObjectiveTo study the relation among methylenetetrahydrofolate reductase (MTHFR) C677T genotypes, dietary habits and the risk of stomach
MethodsA case-control study was conducted with 107 cases of SC and 200 population -based controls in Chuzhou district, Huaian. Jiangsu
province, China. The epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of
the subjects, MTHFR genotypes were detected by PCR-RFLP.
Results(1) The prevalence of the MTHFR C/T or T/T genotypes was found to be significantly different between controls (68.5%) and
SC cases (79.4%. P =0.0416), the increased risk had an adjusted OR of 1.79 (95%CI: 1.01 -3.19). (2) Among subjects who had
a low intake of garlic or Chinese onion, MTHFR C/T or T/T genotypes significantly increased the risk of developing SC. Among
non-tea drinkers or among subjects who had a frequent intake of meat, the carriers of the MTHFR C/T or T/T genotypes had a
higher risk of SC than individuals with the C/C type MTHFR.
ConclusionThe polymorphism of MTHFR C677T was associated with increased risk of developing SC, and that individuals with differing genotypes
may have different susceptibilities to SC, based on their exposure level to environmental factors.
Chinese Journal of Clinical Oncology 04/2012; 1(3):162-166.
ABSTRACT: In order to study the relation between polymorphisms of methylenetetrahydrofolate reductase C677T (MTHFR) and susceptibility of stomach cancer (SC).
We conducted a case-control study with 107 cases of SC and 200 population-based controls in Huaian city of Jiangsu province, China. The epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects. MTHFR genotypes were detected by PCR-RFLP method.
(1) The frequency of MTHFR variant genotypes (C/T + T/T) among the cases (79.4%) was significantly higher than the controls (68.5%) (P = 0.041 6); the crude OR for SC was 1.78 (95% CI: 0.99 - 3.22). After adjustment for sex and age, the OR for SC was 1.89 (95% CI: 1.08 - 3.32). (2) Subjects who had MTHFR variant genotypes and having smoking habit were at a significantly higher risk of developing SC (OR = 7.72, 95% CI: 2.23 - 26.79) compared with those who had wild-type homozygotes (C/C) genotype and no smoking habit. Individuals who had variant genotypes and who had habit of frequent alcohol drinking were at an increased risk of developing SC (OR = 3.08, 95% CI: 1.30 - 7.23) compared with those with C/C genotype and low consumption of alcohol. As compared with subjects with C/C genotype and low consumption of alcohol and no smoking habit, individuals who had variant genotypes and who had habits of frequent alcohol drinking and smoking had 12.96 (95% CI: 2.76 - 70.46) folds risk developing SC.
These results in the present study suggested that the polymorphisms of MTHFR C677T was associated with risk of developing SC, and there was a coordinated effect between MTHFR genotypes and habits of smoking and alcohol drinking in the development of SC.
Zhonghua liu xing bing xue za zhi = Zhonghua liuxingbingxue zazhi 09/2002; 23(4):289-92.
ABSTRACT: Because cytochrome P-450 2E1 (CYP2E1) is involved in metabolic activation of environmental chemical carcinogens, gene polymorphisms that alter its functions may be associated with cancer susceptibility. However, previous studies have revealed disconcordant results with regard to cancer risk. To investigate gene-environment interactions with the RsaI polymorphism of CYP2E1 in terms of risk of esophageal and stomach cancers, we conducted a case-control study with 93 esophageal and 98 stomach cancer cases and 196 population-based controls in a high-endemic area for these cancers of China. We assayed genomic DNA samples for RFLPs in the CYP2E1 by PCR amplification, followed by digestion with RsaI, and collected information on environmental factors by a questionnaire approach. Odds ratios were estimated with an unconditional logistic model, after adjustment for potential confounding factors. The proportional distribution of the homozygous common RsaI alleles did not differ between cancer cases of the esophagus (59.1%) and stomach (59.2%), and controls (61.7%). However, we found a significant positive interaction between the heterozygous and homozygous RsaI rare alleles and ever-smoking in the odds ratio for stomach cancer (P = 0.015). The interaction between the gene polymorphism and dietary factors, such as garlic consumption, was not observed in both cancer cases. These results suggest that gene-environment interactions between the CYP2E1 polymorphism and smoking may have the potential to alter the susceptibility for cancer development in the stomach.
Cancer Epidemiology Biomarkers & Prevention 02/2002; 11(1):29-34. · 4.12 Impact Factor