【摘要】 目的探讨微卫星不稳定性 (MSI)在大肠重复癌与单发癌中的变化规律 ,及MMR、p5 3、Bax、PCNA表达与MSI的关系。 方法采用免疫组化、PCR SSLP法对 38例大肠重复癌患者的 5 1处癌灶及 35例单发大肠癌分别进行MMR、p5 3、Bax、PCNA表达的检测和 5个微卫星位点MSI检测。结果重复癌组复制错误阳性率为 5 3% (2 7/ 5 1) ,单发癌组为 17% (6 / 35 ) ,差异有显著性意义 (χ2 =11 2 5 ,P <0 0 1)。重复癌组中 ,RER+ 与MMR表达缺失有密切的相关性 ;RER+ 与 p5 3表达呈负相关 ;RER+ 组PCNA标记指数显著低于RER-组 ;RER+ 与低分化、近端大肠癌密切相关。结论MSI在大肠重复癌的发生上起着重要作用 ,MSI可作为预测大肠重复癌发生的重要标志。更多还原

【Abstract】 Objective To study microsatellite instability(MSI) in multiple primary colorectal carcinoma(MPCC) and solitary colorectal tumor(SCT), and to explore the relationship between the expression of mismatch repair(MMR)、p53、Bax、PCNA and MSI. Methods The expression of MMR、p53、Bax、 PCNAwere detected by immunohistochemical staining, and MSI at five microsatellite loci were examined by PCR-SSLP in 51 tumors from 38 MPCC patients and 35 SCT cases. Results The replication errors positive phenotype was observed in 27 of 51(53%) tumor foci from MPCC cases, and in 6 of 35(17%) SCT cases. There was an inverse correlation between replication errors (RER) positive and expression of p53; the PCNA labeling index of RER positive tumors were significantly lower than of RER negative tumors; RER positive related strongly with poor differentiation, the proclivity for proximal colon. Conclusions MSI may play an important role in the development of MPCC and may be used as a tumor marker of MPCC.更多还原