Sensitivity analyses were also performed.The rs2267437 polymorphism was associated with a significant increase in risks of overall cancers, breast cancer, renal cell carcinoma and hepatocellular carcinoma, and it could increase the cancer risk in Asian population; the rs5751129 polymorphism could increase the cancer risk in overall cancers; the rs132770 polymorphism was associated with the increased renal cell carcinoma risk; furthermore, the rs132793 polymorphism could decrease breast cancer risk and increase risks in "other cancers".Overall, the results provided evidences that the single nucleotide polymorphisms in XRCC6 promoter region might play different roles in various cancers, indicating different cancers have different tumorigenesis mechanisms.
Compared with the Ku70-1310CC genotype, the CG and CG/GG genotypes had a significantly increased risk of RCC [adjusted odds ratio (OR) = 1.47, 95% confidence interval (CI) = 1.16-1.87 for CG and OR = 1.47, 95% CI = 1.16-1.86 for CG/GG].
These results suggested that the Ku70A-31G polymorphism is involved in the etiology of RCC and, thus, may be a marker for genetic susceptibility to RCC in the Chinese populations.
These evidence suggests that the XRCC6T-991C genotype together with its mRNA expression are involved in the etiology of RCC and may be a marker for susceptibility to RCC in the population of Taiwan.