DNA repair gene polymorphisms, bulky DNA adducts in white blood cells and bladder cancer in a case-control study

Abstract

Individuals differ widely in their ability to repair DNA damage, and DNA-repair deficiency may be involved in modulating cancer risk. In a case-control study of 124 bladder-cancer patients and 85 hospital controls (urological and non-urological), 3 DNA polymorphisms localized in 3 genes of different repair pathways (XRCC1-Arg399Gln, exon 10; XRCC3-Thr241Met, exon 7; XPD-Lys751Gln, exon 23) have been analyzed. Results were correlated with DNA damage measured as 32 P-post-labeling bulky DNA adducts in white blood cells from peripheral blood. Genotyping was performed by PCR-RFLP analysis, and allele frequencies in cases/controls were as follows: XRCC1-399Gln ‫؍‬ 0.34/0.39, XRCC3-241Met ‫؍‬ 0.48/0.35 and XPD-751Gln ‫؍‬ 0.42/0.42. Odds ratios (ORs) were significantly greater than 1 only for the XRCC3 (exon 7) variant, and they were consistent across the 2 control groups. XPD and XRCC1 appear to have no impact on the risk of bladder cancer. Indeed, the effect of XRCC3 was more evident in non-smokers [OR ‫؍‬ 4.8, 95% confidence interval (CI) 1.1-21.2]. XRCC3 apparently interacted with the N-acetyltransferase type 2 (NAT-2) genotype. The effect of XRCC3 was limited to the NAT-2 slow genotype (OR ‫؍‬ 3.4, 95% CI 1.5-7.9), suggesting that XRCC3 might be involved in a common repair pathway of bulky DNA adducts. In addition, the risk of having DNA adduct levels above the median was higher in NAT-2 slow acetylators, homozygotes for the XRCC3-241Met variant allele (OR ‫؍‬ 14.6, 95% CI 1.5-138). However, any discussion of interactions should be considered preliminary because of the small numbers involved. Our results suggest that bladder-cancer risk can be genetically modulated by XRCC3, which may repair DNA cross-link lesions produced by aromatic amines and other environmental chemicals. © 2001 Wiley-Liss, Inc. Key words: bladder cancer; XRCC1; XRCC3; XPD; DNA adductsA potentially important source of interindividual variability in response to carcinogens is DNA-repair capability. Apart from rare recessive inherited syndromes such as ataxia-telangiectasia, Fanconi's anemia and Bloom's syndrome, all of which are characterized by both chromosomal instability and high risk of cancer, and xeroderma pigmentosum, characterized by extreme susceptibility to UV-induced skin cancer, 1 individuals differ widely in the ability to repair DNA damage. 2 Polymorphisms in DNA-repair genes have been described. 3,4 Their role in modulating the risk of environmentally induced cancer is potentially important but has been studied only occasionally. In particular, XPD, XRCC1 and XRCC3 have been proposed as polymorphic genes that might be involved in environmental carcinogenesis. [5][6][7][8][9][10] The XRCC1 protein is involved in the base excision-repair pathway, 11 acting apparently as a scaffold protein, facilitating the repair reaction by binding DNA ligase III at its carboxy and DNA polymerase ␤ to its amino terminus. 12 XRCC3 participates in DNA double-strand breaks/recombinational repair and belongs to an emerging family of Rad51-related prot...

DNA adduct levels and DNA repair polymorphisms in traffic-exposed workers and a general population sample

“…11 A similar, although not statistically significant, effect was possibly suggested also for XRCC1, in agreement with the studies by Lunn et al 12 and Duell et al 16 A still weaker effect was shown for XRCC3-241 polymorphism for which, however, evidence of its possible involvement in DNAadducts repair has been provided. 18 Approximately two-thirds of our study subjects had at least a Gln variant at XPD-751 polymorphic locus, and tended to show higher levels of DNA adducts than subjects with 2 normal alleles. This difference was evident among traffic-exposed workers, suggesting a role for this polymorphism at higher levels of exposure.…”

“…PCR followed by enzymatic digestion was used for the genotyping of the XRCC1-Arg399Gln (G28152A, exon 10), XRCC3-Thr241Met (C18067T, exon 7) polymorphisms and XPD-Lys751Gln (A35931C, exon 23). 14,18 All of the PCR reactions were performed in a total reaction volume of 20 l containing 10 ng of genomic DNA, 0.4 units of Taq polymerase (PE applied biosystems) in PCR buffer 1ϫ, 1.5 mM MgCl 2 , 50 mM dNTPs and 250 nM of each primer. Thermal cycling conditions were as follows: initial denaturation step at 95°C for 3 min, 35 cycles of PCR consisting of 95°C for 20 sec, 20 sec at the appropriate annealing temperature (55°C, 67°C and 60°C, respectively), 72°C for 20 sec and a final extension step at 72°C for 5 min.…”

“…Thermal cycling conditions were as follows: initial denaturation step at 95°C for 3 min, 35 cycles of PCR consisting of 95°C for 20 sec, 20 sec at the appropriate annealing temperature (55°C, 67°C and 60°C, respectively), 72°C for 20 sec and a final extension step at 72°C for 5 min. The following PCR primers and restriction enzymes were used to detect genotypes as described in Matullo et al 18 : XRCC1-Arg399Gln, primer sense 5Ј-CAAGTACAGCCAG-GTCCTAG-3Ј, antisense 5Ј-CCTTCCCTCA TCTGGAGTAC-3Ј (Nci I, Promega); XRCC3-Thr241Met, primer sense 5Ј-GCCTG-GTGGTCATCGACTC-3Ј, antisense 5Ј-ACAGGGCTCTGGAA-GGCACTGCTCAGC TCACGCACC-3Ј(Nco I, Promega); XPDLys751Gln, primer sense 5Ј-CTGCTCAGCCTGGAGCAGCTAGA ATCAGAGGAGACGCTG-3Ј, antisense 5Ј-AAGACCTTCTAGC-ACCACCG-3Ј (Pst I, Promega).…”

“…12 In particular, xeroderma pigmentosum group D (XPD, also known as ERCC2) and x-ray repair cross complementing group 1-3 (XRCC1 and XRCC3) genes have been reported to be polymorphic and might be involved in environmental carcinogenesis. [12][13][14][15][16][17][18] The XRCC1 protein participates in the BER pathway, 19 acting apparently as a scaffold protein, facilitating the repair reaction by binding DNA ligase III at its carboxy and DNA polymerase ␤ to its amino terminus. XRCC3 participates in DNA double-strand break/recombination repair and is a member of an emerging family of Rad-51-related proteins that likely participate in homologous recombination to maintain chromosome stability and repair DNA damage.…”

A variant of the DNA repair gene XRCC3 and risk of squamous cell carcinoma of the head and neck: A case‐control analysis

“…25 Although the functional relevance of this polymorphism is unknown, it was reported recently that the XRCC3 C18067T polymorphism is associated with risk for melanoma 26 and bladder cancer. 27 In our study, we hypothesized that genetic variant of XRCC3 may contribute to genetic susceptibility to SCCHN and therefore would occur at different frequencies in individuals with and without cancer. To test this hypothesis, we performed a hospital-based case-control study using a polymerase chain reaction (PCR)-single-strand conformation polymorphism (SSCP) assay to genotype the variant of XRCC3 in 367 patients with SCCHN and 354 cancer-free controls.…”