The polymorphismXRCC1Arg194Trp and 8-hydroxydeoxyguanosine increased susceptibility to arsenic-related renal cell carcinoma
This study was designed to explore the relationship between X-ray repair cross-complementing group 1 (XRCC1) gene polymorphisms and renal cell carcinoma (RCC) and to investigate whether individuals with an XRCC1 risk genotype, a high level of 8-OHdG or a high urinary total arsenic concentration have a modified odds ratio (OR) of RCC. We recruited 180 RCC patients and 360 age- and sex-matched controls from a hospital-based pool. Image-guided biopsy or surgical resection of renal tumors was performed on RCC patients for pathological verification. Genomic DNA was used to examine the genotype of XRCC1(Arg399Gln), XRCC1(Arg194Trp), XRCC3(Thr241Met) and XPD(Lys751Gln) by PCR-RFLP. Liquid chromatography with tandem mass spectrometry was used to determine urinary 8-OHdG levels. A HPLC-HG-AAS was used to determine the concentrations of urinary arsenic species. Participants with the genotype XRCC1(Arg194Trp) Arg/Trp + Trp/Trp had a significantly higher OR of RCC than those with the Arg/Arg genotype; the OR and 95% confidence interval was 0.66 (0.45–0.97) after multivariate adjustment. The OR of RCC for the combined effect of high urinary 8-OHdG levels and high urinary total arsenic concentration in individuals with a XRCC1(Arg194Trp) Arg/Trp + Trp/Trp genotype was higher than in patients with an Arg/Arg genotype, which was evident in a dose response manner. In conclusion, this is the first study to show that the XRCC1 Arg194 allele is a predicting factor for RCC. The more risk factors (high urinary 8-OHdG levels, high urinary total arsenic concentrations, and XRCC1 Arg194 allele) that were present, the higher the OR of RCC.