The Involvement of ERCC2/XPD and ERCC6/CSB Wild Type Alleles in Protection Against Aging and Cancer

Background. DNA helicases maintain genome stability, and their deficiency is associated with disorders resembling premature aging as well as contributes to carcinogenesis. Their functions are determined by the respective genes encoding nucleotide excision repair initiating proteins, e.g. XPD and CSB. Objective. The present study aimed to investigate the influence of genetic variations in ERCC2/XPD (rs1799793, rs13181) and ERCC6/CSB (rs2228526, rs2228528) loci on lifespan and developing age-related bladder cancer focusing on homozygous wild type alleles. Method. The allelic variants were identified in 354 clinically healthy controls and 418 bladder cancer patients using the PCR-RFLP method. Results. The age-depended increase in frequencies of homozygous carriers of wild-type XPD 312Asp and XPD 751Lys alleles was observed among controls, especially among subjects over 80 years (r = 0.67, p = 0.012). The statistically significant correlation was also found between the frequency of homozygous wild type alleles at all tested loci and age in healthy population over 60 years (r = 0.35, p = 0.046) suggesting the relationship between lifespan and longevity, on the one hand, and normal functioning of these genes and their products, on the other hand. Homozygous carriers of wild type alleles were less susceptible to bladder cancer, tumor invasion, increase in grade of malignancy and recurrence, but their effects were specific with respect to clinicopathological and lifestyle characteristics. Conclusion. Homozygous wild type alleles encoding XPD and CSB proteins with optimal properties were shown to affect human lifespan, risk of developing bladder cancer, its progression and recurrence under certain conditions.