[Association of GSTP1 and PLCE1 gene polymorphisms with primary esophageal cancer]

To assess the association of polymorphisms of glutathione S-transferase P1 (GSTP1) and phospholipase C epsilon-1 (PLCE1) genes with the susceptibility of primary esophageal cancer and their interaction with environmental factors.

162 patients with primary esophageal cancer and 162 healthy controls were recruited in this cross-sectional study. Basic information such as gender, age, history of smoking and alcohol consumption and family history of esophageal cancer were collected. Single nucleotide polymorphisms at A105G locus of GSTP1 gene and rs3765524, rs2274223 and rs3781264 loci of PLCE1 gene were detected. A logistic regression model was established to analyze the risk factors of esophageal cancer and the interaction among the factors.

The proportions of individuals with smoking history, family history of esophageal cancer and hot diet in esophageal cancer group were higher than those in the control group (P<0.05). Conditional Logistic regression analysis showed that smoking, family history of esophageal cancer and GG genotype at the rs2274223 locus of PLCE1 gene were the risk factors for esophageal cancer (P<0.05), and AG/GG genotypes at the A105G locus of GSTP1 gene were the protective factors for esophageal cancer (P<0.05). In the two-factor interaction model, both AA genotype at A105G locus of GSTP1 gene and GG genotype at rs2274223 locus of PLCE1 gene had an interaction with smoking, and the risk of esophageal cancer has increased by 83.6% and 85.7%, respectively (P<0.05). AA genotype at A105G locus of GSTP1 gene, GG genotype at rs2274223 locus of PLCE1 gene and smoking constituted the best three-factor interaction model, and the risk of esophageal cancer has increased by 244.0% (P<0.05). Four-factor interaction model analysis showed that the risk of esophageal cancer among individuals with AA genotype at A105G locus of GSTP1 gene, GG genotype at rs2274223 locus of PLCE1 gene, smoking and family history of esophageal cancer has increased by 264.4% (P<0.05).

The AG and GG genotypes at the A105G locus of GSTP1 gene are protective factors for esophageal cancer, and the GG genotype at rs2274223 locus of PLCE1 gene is a risk factor, both of them may interact with smoking and affect the susceptibility to esophageal cancer.