Research On The Relationship Between Polymorphisms Of XPD Gene And Lung Cancer Susceptibility

Excision repair cross-complementing group 2(ERCC2)/Xeroderma pigmentosum complementation group D(XPD),a major DNA repair protein,is involved in nucleotide excision repair and basal transcription.To determine the effect of the ERCC21XPD Lys751Gln(A35931C)at exon23 polymorphism on the risk of lung cancer in a Northern Chinese population,a hospital-based case-control study was designed consisting of 253 newly diagnosis and previously untreated subjects with lung cancer and 260 cancer-free control subjects matched on age(±5 years),gender and ethnicity.All subjects were unrelated ethnic Han Chinese.In the whole study group,the distribution of allele frequency associated with polymorphisms of ERCC2/XPD Lys751Gln(A35931C)differed between cases and controls(P=0.00). When stratifications analyzed,the variant C allele of ERCC2/XPD Lys751Gln(A35931C)was associated with increased risk of squamous carcinoma of lung(CC/AC versus AA,adjusted OR=6.36,95%CI=3.52-12.54)(P=0.00).When smoking duration were considered,presence of one or two variant C alleles was associated with increased risk for lung cancer(OR=10.67 95%CI=2.28-49.81) (P=0.00)and squamous carcinoma of lung(OR=12.16,95%CI=2.70-54.68) (P=0.00)among never smokers only,but similar findings were not seen among never smokers.These results suggest a possible gene-environment interaction,but the findings are limited due to the relatively small numbers in the subgroups.This is the first study to report a significant association of a polymorphism in ERCC2/XPD Lys751Gln(A35931C)with risk of lung cancer in northen China.Our results suggest ERCC2/XPD Lys751Gln(A35931C)C allele a potential risk factor that for squamous carcinoma of lung and increase lung cancer among smokers in this Chinese population,but larger studies are needed to confirm these findings.