OBJECTIVEThis study aimed to explore the roles of three common single nucleotide polymorphisms in the X-ray repair cross-complementing group-1 gene (XRCC1) and of life style factors and their possible interactions in the risk of esophageal squamous cell carcinoma (ESCC) in China.

METHODSA population-based case-control study of 432 cases and 915 controls was conducted in Yangzhong County, Jiangsu Province, China. Subjects were interviewed by trained interviewers using a structured questionnaire that included questions on demographics and life style. XRCC1 genotypes were analyzed using a polymerase chain reaction based restriction fragment length polymorphism (PCR-RFLP) assay. Unconditional logistic regression analysis was used to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs) for associations of ESCC with XRCC1 polymorphisms and lifestyle-related factors.

RESULTSBoth the drinking of river water and alcohol intake history were significantly associated [SW1]with an increased risk of ESCC among men with aORs of 4.20 (95% CI: 2.90-6.07) and 2.03 (95% CI: 1.43-2.89), respectively. For women, the corresponding odds ratios were 8.37 (95% CI: 5.09-13.75) for river water drinking and 12.78 (95% CI: 2.69-60.69) for long-term stored rice intake. After the XRCC1 G28152A polymorphism was adjusted for potential confounders, subjects with GA and AA genotypes had an increased risk for ESCC (aOR: 1.21, 95% CI: 0.93-1.56), compared with subjects with a GG genotype, and a positive multiplicative interaction between intake of long-term stored rice and the XRCC1 G28152A polymorphism was observed (P=0.009).

CONCLUSIONSOur findings suggest that both lifestyle-related factors, including drinking river water, long-term stored rice and alcohol intake, and the XRCC1 G28152A polymorphism were possible risk factors for ESCC, and that the XRCC1 G28152A polymorphism modified the effect of long-term stored rice intake on the risk of ESCC among Chinese people.