ABSTRACT: To test the hypothesis that, in the Southeastern Brazilian population, the GSTT1, GSTM1 and CYP2E1 polymorphisms and putative risk factors are associated with an increased risk for gastric cancer.
We conducted a study on 100 cases of gastric cancer (GC), 100 cases of chronic gastritis (CG), and 150 controls (C). Deletion of the GSTT1 and GSTM1 genes was assessed by multiplex PCR. CYP2E1/PstI genotyping was performed using a PCR-RFLP assay.
No relationship between GSTT1/GSTM1 deletion and the c1/c2 genotype of CYP2E1 was observed among the three groups. However, a significant difference between CG and C was observed, due to a greater number of GSTT1/GSTM1 positive genotypes in the CG group. The GSTT1 null genotype occurred more frequently in Negroid subjects, and the GSTM1 null genotype in Caucasians, while the GSTM1 positive genotype was observed mainly in individuals with chronic gastritis infected with H pylori.
Our findings indicate that there is no obvious relationship between the GSTT1, GSTM1 and CYP2E1 polymorphisms and gastric cancer.
World Journal of Gastroenterology 06/2004; 10(9):1240-5. · 2.47 Impact Factor
ABSTRACT: To evaluate the influence of GSTM1 and GSTT1 null genotypes in head and neck carcinogenesis.
The frequencies of GSTM1 and GSTT1 null genotypes were evaluated by multiplex polymerase chain reaction (PCR) in 45 patients with head and neck squamous cell carcinoma and in 45 control group individuals. Both groups were composed of smokers paired by gender, age and race.
The GSTT1 null genotype was found in 24.4% of the patients and 17.7% of the control group (P= 0.606), while 44.4% of the patients and 48.8% of the control group were bearers of the GSTM1 null genotype (P=0.832). No associations between GSTT1 and GSTMI null genotypes and primary tumor sites were found.
In our study, it was impossible to establish the influence of the GSTT1 and GSTM1 null genotypes in head and neck carcinogenesis.
Revista da Associação Médica Brasileira 52(5):365-8. · 0.77 Impact Factor
ABSTRACT: Gene variability related to carcinogen activation and detoxification may interfere with susceptibility to head and neck cancer.
To investigate the relation between GSTT1 and GSTM1 null polymorphisms and the risk of head and neck squamous cell carcinoma in cigarette smokers.
A case-control study conducted at the Sao Jose do Rio Preto Medical School, Brazil. GSTM1 and GSTT1 null genotype frequencies were evaluated by multiplex PCR in 45 cigarette smokers with head and neck squamous cell carcinomas and 45 cigarette smokers without this disease.
The oral cavity was the most prevalent tumor site for squamous cell carcinoma. The GSTT1 null genotype was found in 33.3% of the Experimental Group and 23.3% of the Control Group (p= 0.311). Experimental and Control Groups had GSTM1 null genotype frequencies of 35% and 48.3% (p=0.582). No association between alcohol consumption and GSTT1 and GSTMI null genotypes was found in these groups (p-values>0.05). There were more men, and alcohol consumption was prevalent in both groups.
In this study we were unable to show a correlation between GSTM1 and GSTT1 genotypes and the development of head and neck squamous cell carcinomas in cigarette smokers.
Brazilian journal of otorhinolaryngology 72(5):654-8.