p53基因第72位密码子多态与食管癌风险

p53 gene codon 72 polymorphism and susceptibility to esophageal squamous cell carcinoma in a Chinese population

目的 研究 p5 3基因第 72位密码子 Arg/ Pro多态与食管癌遗传易感性的关系。方法 采用聚合酶链反应 -限制性片段长度多态性方法检测了 91例食管癌患者与 2 0 4名正常对照的 p5 3Arg/ Pro基因型分布及差异。结果 正常对照组 p5 3Pro等位基因频率 (0 .5 88)与病例组 (0 .480 )比较差异无显著性(P=0 .11)。但 3种 p5 3基因型频率在病例组和对照组的分布差异有显著性 ,病例组的 Pro/ Pro基因型频率 (39.6 % )显著高于对照组 (2 1.1% )。携带 Pro/ Pro纯合变异基因型者患食管癌的风险比携带 Arg/ Arg纯合野生基因型者高 2倍 [校正比值比 (odds ratio,OR)为 2 .18,95 %可信区间 (confidence interval,CI)为1.10～ 4.35。杂合子基因型 (Arg/ Pro)与食管癌的遗传易感性无关 (校正 OR=0 .84,95 % CI=0 .42～1.6 8)。吸烟增加食管癌风险 (OR=2 .30 ,95 % CI=1.30～ 4.12 ) ,但与 Pro/ Pro基因型无协同作用。结论p5 3基因第 72位密码子纯合突变是中国人的食管癌易感因素。

Objective: To investigate the relationship between p53 codon 72 polymorphism and susceptibility to esophageal squamous cell carcinoma in China. Methods The p53 genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism among 204 healthy controls and 91 patients with esophageal squamous cell carcinoma (ESCC). Results There was no significant difference between patients and controls with respect to allele frequency for the p53 Pro allele (0. 480 versus 0. 588, P=0. 11); however, the Pro/Pro genotype of p53 among cases (39.6%) was significantly (P<0. 05) more frequent than that among controls (21.1%). Subjects homozygous for the p53 Pro allele had a more than 2-fold increased risk of developing ESCC (OR=2.18; 95% CI=1.10-4.35, adjusted for age, sex, and smoking), whereas the Arg/Pro genotype was not associated with elevated risk of the cancer (adjusted OR=0.84; 95% CI=0.42-1.68). No interaction between smoking and Pro/Pro genotype was observed for risk of ESCC. Conclusion The p53 codon 72 polymorphism may play a role in susceptibility to esophageal carcinogenesis.