胃癌中E-cad的表达及启动子甲基化的临床意义

目的探讨E-cad（上皮型钙黏素）在胃癌和癌旁组织中的表达及其启动子甲基化状态与胃癌发生、发展、转移和预后等生物学特性的关系。方法应用免疫组织化学SP法和MSP（甲基化特异PCR法）,检测38例癌旁组织和72例胃癌组织中E-cad的表达情况及其启动子甲基化状态。结果癌旁组织均表达E-cad,而胃癌组织E-cad阴性表达率为63.89%（46/72）,其表达缺失与胃癌的分化程度、临床分期、肿瘤浸润深度密切相关（P〈0.05）。在癌旁组织中无E-cad启动子甲基化,而胃癌组织E-cad启动子甲基化发生率为56.94%（41/72）。随着肿瘤的去分化,临床分期增高,肿瘤浸润深度增加和淋巴转移E-cad启动子甲基化率逐渐增加（P〈0.05）。结论E-cad表达缺失和启动子甲基化与胃癌的发生、发展及预后密切相关,启动子甲基化是E-cad表达缺失的重要原因。

Expression of E-cad and Its Promoter Methylation Status in Gastric Carcinoma

Objective To investigate the protein expression of E-cad and its promoter methylation status to evaluate their clinical value in gastric carcinoma.Methods 38 cases of para-cancinoma tissue and 72 cases of gastric carcinoma were studied by immunohistochemical SP method and Methylation-Specific-PCR(MSP).Results The negative rate of E-cad was 0 and 63.89%(46/72) in para-cancinoma tissue and gastric carcinoma;its expression was releted with clinical stage,tumor invasion depth and grade(P<0.05).The methylation rate of E-cad promoter was 0 and 56.94%(41/72) in paracancinoma tissue and gastric carcinoma.Its methylation status was associated with clinical stage,tumor invasion depth,lymph metastasis and grade.Conclusion E-cad loss and its promoter methylation may play an important role in gastric carcinogenesis,progression and worse prognosis in gastric cancer,the promoter methylation may be the key reason for E-cad negative expression.