膀胱移行细胞癌中TMIP-3 CpG岛DNA甲基化的研究

Study of CpG Island Methylation of TIMP-3 Gene in Human Transi- tional Cell Carcinoma of Bladder

目的检测膀胱移行细胞癌中金属蛋白酶组织抑制因子3（tissue inhibitor of metalloproteinase 3,TIMP-3）CpG岛甲基化程度，探讨该基因CpG岛甲基化在该肿瘤中的作用及临床意义。方法收集60例膀胱移行细胞癌组织标本和30例正常膀胱粘膜标本，用甲基化特异的PCR（methylmion specific PCR，MSP）法检测TIMP-3基因CpG岛的甲基化状态。结果膀胱移行细胞癌TIMP-3基因CpG岛的甲基化发生率为45％（27／60）。而出现甲基化的膀胱癌病例，其TIMP-3的蛋白表达水平均不高。结论膀胱癌细胞TIMP-3基因的CpG岛甲基化发生率较高，检测其表达水平对膀胱移行细胞癌的诊断及预后判断具有一定的参考价值。

Objective To detect aberrant CpG island methylation of tissue inhibitor of metalloproteinase 3 （TIMP-3） gene and to discuss the function of TIMP-3 and its clinical significance in tumor. Methods Methylation of TIMP-3 gene CpG island was detected by methylation-specific PCR （MSP） in 60 samples of human bladder carcinoma （tumor group）, and 30 normal bladder samples （control group）. Results Among 60 bladder carcinoma samples, 50% （33 cases） showed CpG island methylation of TIMP-3, with low expression level of TIMP-3. Conclusion The CpG island hypermethylation of TIMP-3 is increased in bladder cancer. Detection of TIMP-3 expression level might be referred as a diagnostic and prognostic marker for transitional cell carcinoma of bladder.