肝细胞肝癌CDH1基因启动子C／A单核苷酸多态性与蛋白表达的关系

Relationship between-160C/A polymorphism in CDHlgene promoter and protein expression in hepatocellular carcinoma

目的探讨原发性肝细胞肝癌CDHl基因启动子-160位点的C／A单核苷酸多态性（SNP）与其蛋白表达的关系。方法以34例肝癌手术病人为对象，DNA直接测序法检测其血液标本中CDH1基因启动子-160位点C／ASNP，免疫组化法检测组织标本中CDH1的蛋白产物——上皮钙黏素（E-cadherin）的表达情况，比较分析C／ASNP与E—cadherin表达的关系。结果E—cadherin高表达组18例（52．9％），低表达组16例（47．1％），两组的基因型出现率CC与CA，AA比较差异均有统计学意义（P（0．05），CA与AA间差异无统计学意义（P〉0．05），A、C等位基因频率在两组差异有统计学意义（P〈O．05）。结论CDH1基因启动子-160位点的C／ASNP在肝癌E-cadherin表达中可能发挥重要作用，且A等位基因的出现与E—cadherin表达下调相关。

Objective To investigate the relationship between-160C/A single nucleotide polymorphism（SNP） in the CDH1 gene promoter and protein expression in hepatocellular carcinoma. Methods Samples were taken from 34 patients with hepatocellular carcinoma and -160 C/A SNP of CDHI gene promoter was detected by blood specimens adopting direct DNA sequencing. The expression of E-cadherin which encoded by CDH1 gene was determined by paraffin-embedded tissue using immunohistochemistry and the association Between -160 C/A SNP and protein expression was analyzed. Results The high and low expression of E-cadherin was observed in 18 cases（52.9%） and 16 cases（47.1%）. In these two groups, the difference of the incidence between CC genotype and CA, AA genotype was statistically significant（P〈0.05） whereas there was no marked difference between CA and AA genotype. The difference of both A and C allele frequency was significant（P〈0.05）. Conclusion The -160 C/A SNP of the CDH1 gene promoter may play an important role in regulating the expression of E-eadherin in hepatocellular carcinoma and the incidence of A allele is associated with down-regulation of E cadherin expression.