Association Study On Single Nucleotide Polymorphism In XRCC1,ERCC1 And Concurrent Chemoradiotherapy Response And Survival In Esophageal Squamous Cell Carcinoma

Objective To investigate whether the single nucleotide polymerphisms(SNP) in DNA repair gene XRCC1(X-ray cross-complementing group1), ERCC1(Excision repair cross-complementing group 1) were associated with the short term effect, metastasis or recurrence and the survival of the concurrent chemoradiotherapy in esophageal squamous cell carcinoma(ESCC).Methods The single nucleotide polymorphisms(SNP) in DNA repair gene XRCCl-399 and ERCC1-118 of the 50 esophageal squamous cell carcinoma patients(ESCC) who received the concurrent chemoradiotherapy were assessed with 5, nuclease allelic discrimination assay(Taq Man) by real-time PCR.The genotypes were tested for an association with the short term effect,metastasis or recurrence and the survival of the concurrent chemoradiotherapy.Results The 50 ESCC patients were treated with concurrent chemoradiotherapy. The complete response(CR) rate in patients with XRCC1-399 A/A genotype was higher than XRCC1-399 G/G genotype. The complete response(CR) rate in patients with ERCC1-118 carrying one or two C allele(C/C or C/T genotype) was higher than ERCC1-118 without carrying the C allele(T/T genotype), There was a significant difference between them(P=0.014, P=0.040). During the follow-up period, the risk of metastasis or recurrence in patients with XRCC1-399 A/A genotype was effectively lower than the XRCC1-399 G/G genotype(P=0.031), while ERCC1-118 gene polymorphism has nothing to do with the risk of metastasis or recurrence(P=0.886). Combined with the univariate and multivariable analysis of Cox hazard regression model suggested that ERCC1-118 gene polymorphism is closely related with the survival time, the average survival time of the patients with ERCC1-118 carrying one or two C allele(C/C or C/T genotypes) was more significantly prolonged than ERCC1-118 without carrying C(T / T genotype)(HR=12.96, 95%CI=3.08~54.61, P<0.001; HR=11.71, 95%CI=3.06~44.83, P<0.001), while the polymorphism of XRCC1-399 gene was not connect with the survival time(P=0.283,P=0.208).Conclusion The complete response rate in ESCC patients with XRCC1-399 A/A genotype who were treated with concurrent chemoradiotherapy was higher,and the risk of metastasis or recurrence in those patients was effectively lower. The complete response rate in ESCC patients with ERCC1-118 carrying one or two C allele(C/C or C/T genotype) who were treated with concurrent chemoradiotherapy was higher.,and the average survival time in those patients was more significantly prolonged.