X-ray repair cross-complementing group 1 (XRCC1) single-nucleotide polymorphisms and the risk of salivary gland carcinomas.
BACKGROUND
X-ray repair cross complementing group 1 (XRCC1) is important in the repair of single-strand DNA breaks caused by endogenous oxidative species and exogenous carcinogens.


METHODS
This tertiary cancer center-based, case-control association study included 138 patients with salivary gland carcinoma (SGC), 50 patients with benign salivary gland tumors, and a group of 503 cancer-free control participants. Polymerase chain reaction-restriction fragment length polymorphism genotyping assays were performed on 6 XRCC1 single-nucleotide polymorphisms (SNPs). Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated in multivariate logistic regression analyses, and haplotype distributions were estimated.


RESULTS
The XRCC1 genotype distributions of patients with SGC and control participants differed significantly for both the T1915C promoter SNP (P = .047) and the Arg194Trp coding region SNP (P = .037). The polymorphic 1915C allele was significantly less frequent in patients with SGC than in the controls (34% vs 42%; P = .031). Multivariate analysis demonstrated that individuals who had the 1915 polymorphic homozygous CC genotype (OR, 0.4; 95% CI, 0.2-0.9; P = .017) had a significantly lower risk of SGC, and individuals who had the Arg194Trp heterozygous CT genotype (OR, 1.6; 95% CI, 1.0-2.6; P = .059) had a higher, borderline significant risk. The CGTTGG haplotype was associated with a higher SGC risk (OR, 3.5; 95% CI, 1.1-11.3; P = .036). No findings were significant for the patients who had benign salivary gland tumors.


CONCLUSIONS
In this study, the XRCC1 1915C allele was associated with a lower SGC risk, and the XRCC1 194Trp allele was associated with a higher SGC risk.
Ho
Tang
T
Department of Head and Neck Surgery, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
Li
Guojun
G
Lu
Jiachun
J
Zhao
Chong
C
Wei
Qingyi
Q
Sturgis
Erich M
EM
D000328:Adult; D016022:Case-Control Studies; D004268:DNA-Binding Proteins / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008875:Middle Aged; D012307:Risk Factors; D012468:Salivary Gland Neoplasms / Q000235:genetics*; D000076105:X-ray Repair Cross Complementing Protein 1
D004268:DNA-Binding Proteins; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human