In a subgroup analysis by ethnicity, GSTT1 null genotype was correlated with a significantly increased risk of esophageal cancer among Asians (OR = 1.33; 95% CI 1.12-1.58; <i>P</i> < 0.05), instead of Caucasians or Africans (OR = 0.91; 95% CI 0.65-1.26; <i>P</i> > 0.05 for Caucasians and OR = 1.32; 95% CI 0.98-1.77; <i>P</i> > 0.05 for Africans).
Analyses of the GSTT1 polymorphisms indicated a positive correlation between the GSTT1 null genotype and the EC risk (OR = 1.233, 95% CI = 1.044-1.455, p for heterogeneity <0.001).
In this study, we assessed the association of functional polymorphisms in GSTM1 and GSTT1 with esophageal cancer in Kashmir, India, an area with a high incidence of esophageal squamous cell carcinoma (ESCC).
A significant association of GSTM1 null genotype with esophageal cancer was observed in a younger age group in Assam (OR-2.7, 95 % CI, 1.48-5.01), and in Delhi population association was observed in smokers with GSTT1 null genotype (OR-2.5, 95 % CI, 1.04-6.07), and alcoholics having GSTM1 null genotype (OR-2.6, 95 % CI, 0.99-6.77).
Subgroup analyses by ethnicity showed there was an obvious association between GSTT1 null genotype and increased risk of esophageal cancer in East Asians (OR = 1.24, 95 % CI 1.10-1.39, P < 0.001), but not in Caucasians (OR = 0.89, 95 % CI 0.71-1.11, P = 0.300).
The cumulative meta-analysis showed a trend of an obvious association between GSTT1 null genotype and esophageal cancer risk as information accumulated by year.
The results showed that GSTM1 null genotype and GSTT1 null genotype were significantly associated with increased risk for esophageal cancer in Chinese population.
Genetic polymorphisms of GSTM1, GSTT1 and GSTP1 in association with some environmental factors and their impact on esophageal cancer susceptibility were assessed in the Iranian population.
A case-control study was performed in 135 EC patients and 195 healthy controls to analyze association of polymorphisms in glutathione S-transferase (GST) mu (GSTM1), GST theta (GSTT1), GST pi (GSTP1), GSTM3, Cytochrome P450 (CYP)1A1, and CYP2E1 genes with susceptibility to EC as well as their interaction with environmental factors such as smoking and high consumption of salted tea in Kashmir valley.
ALDH2, MTHFR C677T, CYP1A1 Ile/Val, CYP1A1MspI, CYP2E1, GSTP1, GSTM1 and GSTT1 were examined by meta-analyses and significant relations were found between ALDH2*1*2 and the CYP1A1 Val allele and increased risk of esophageal cancer.
GSTM1, GSTT1, GSTP1 and CYP1A1 genetic polymorphisms and susceptibility to esophageal cancer in a French population: different pattern of squamous cell carcinoma and adenocarcinoma.