XRCC1基因多态性与食管鳞癌放疗敏感相关性分析

The relationship between gene polymorphism and the sensitivity of radio therapy for the patients with esophageal squamous cell carcinoma

目的了解食管鳞癌患者的X射线交错互补修复基因1(X-ray repair cross complementing group1,XRCC1)的4个单核苷酸多态性(single nucleotide polymorphisms,SNP)位点的分布情况及其与放疗敏感性的关系。方法提取175例食管鳞癌患者外周血DNA,通过特异性引物PCR扩增XR CC1的4个SNP所在基因片段,测序及BLAST多态性分析,并与放疗结果相结合,分析SNP与放疗疗效的相关性。结果175例食管鳞癌患者中有112例能成功扩增并测序XR CC1中4个SNP位点。112例患者全组放疗近期有效率为84.8%,其中,4个SNP位点均未变异的基因型组有效率为74.3%,有1个以上SNP变异的基因型组有效率为89.6%(χ^(2)=4.389,P=0.036);单独第4个SNP位点(G28152 A,Arg399Gln)变异的基因型组和所有含第4个SNP位点变异组有效率分别为91.2%和91.5%,与未变异的基因型组比较差异有统计学意义(χ^(2)=4.014,P=0.045和X2=4.451,P=0.035)。结论XRCC1中SNP变异基因型组与食管鳞癌患者放疗敏感性相关。其中,第4个SNP位点变异的基因型可能是放疗敏感的预测指标。

Objective To detect four single nucleotide polymorphisms(SNP)of X-ray repair cross complementing group 1(XRCC1)in the patients with esophageal squamous cell cancer(ESCC),and learn the distribution of genotypes of four SNPs among the patients with ESCC.To study the relationship between four SNPs of XRCC1 and the sensitivity of radio therapy for the patients with ESCC for clinical history diagnosis.Method The DNA was extracted the whole blood from 175 cases ESCC patients.The complete XRCC1 gene sequence was amplified with three pairs of primers,and then sequenced in Invitrogen Biotechnology Co.Ltd.The BLAST 2.0 software online were used to analyze and identify mismatches.To analysis the relationship between four SNPs of XRCC1 and the effectiveness of radio sensitivity by connecting the result of radio therapy.Results 112 complete XRCC1 genes were successfully amplified and sequenced in 175 cases of in the patients with ESCC.The response rate of radiotherapy is 84.8%among 112 cases.The distribution of genotypes of the SNPs among the radiosensitive and radio-resistant in the sensitivity of radio therapy for the patients with ESCC,genotype frequency with and without variation of the four SNPs in XRCC1 genes was statistic different(χ^(2)=4.389,P=0.036).Among the different genotype group,only group with mutation of G28152 A has statistic different sensitivity to the radiotherapy for ESCC,compared with group with no mutations of the four SNP in XRCC1 gene(χ^(2)=4.014,P=0.045),and all of the groups containing the fourth mutatio of G28152 A has statistic different sensitivity to compared with group with no mutations of the four SNP in XRCC1 gene(χ^(2)=4.451,P=0.035).Conclusion The polymorphism of four SNPs of XRCC1 are associated with the sensitivity of radio therapy for the patients with ESCC.The fourth SNP is the gene type of sensitivity of radio therapy and predictive ability.