Abstract
An association between genetic polymorphisms in encoding X-ray repair cross complementing group 1 (XRCC1) and encoding xeroderma pigmentosum group D (XPD) and risks of non-small-cell lung cancer (NSCLC) in East Chinese Han population has been observed. Herein we hypothesized that genetic polymorphisms in these two DNA repair genes are likely to be important in the NSCLC in Chinese nonsmoking female patients. We recruited 327 nonsmoking female patients with NSCLC and 342 individuals with benign lung diseases or healthy controls. Genotype frequencies of XRCC1 T-77C, Arg194Trp, Arg280His and Arg399Gln, Pro206Pro, and XPD Asp312Asn and Lys751Gln were calculated after Polymerase Chain Reaction amplification and sequencing. Generalized multifactor dimensionality reduction (GMDR) was used to detect the interactive effect of XRCC1 and XPD gene polymorphisms. The ratio of cooking oil mist exposure history and soot exposure history, and the gene frequencies of XRCC1 T-77C TC + CC, XRCC1 AG + GG, XRCC1 399Gln/Gln, and XPD 751Gln/Gln were higher in female patients with NSCLC than those with benign lung diseases or healthy controls. The haplotypes of XRCC1 T-Arg-Arg-Gln and XRCC1 C-Arg-Arg-Arg were positively associated with the NSCLC occurrence in nonsmoking female patients. GMDR discovered that there was an interactive model of XRCC1 and XPD genes in multiple gene loci. Logistic regression analysis showed that XRCC1 T-77C, XRCC1 Pro206Pro polymorphism, cooking oil mist and soot exposure history and tumor-node-metastasis (TNM) stage were related to NSCLC occurrence for nonsmoking female patients. Taken together, XRCC1 and XPD polymorphisms, cooking oil mist, and soot exposure history may be interactively correlated with NSCLC incidence for nonsmoking female patients.