贲门癌mdm2 基因扩增及蛋白表达的研究

 目的 检测贲门癌组织中mdm2基因扩增及蛋白表达，探讨其在贲门癌发生发展中的作用，分析其临床病理意义。方法 用dPCR技术检测贲门癌组织mdm2基因扩增；用免疫组织化学技术及流式细胞术检测mdm2蛋白表达水平。结果 该组标本中18．42％有mdm2基因扩增，64．86％有mdm2蛋白过表达，其mdm2表达FJ值（1．45±0．34）明显高于正常黏膜组织的FJ值（1．00±0．13，P〈0．05）。高中分化的贲门癌组织，mdm2基因扩增率及蛋白表达水平均较低分化者高（33．30％Vs5．00，80．00％VS47．06％，P〈0．05）。结合该组标本此前已检测的p53基因突变和蛋白表达结果发现，两种基因及蛋白表达异常在本组标本中的分布有不重叠趋势。结论 dm2基因扩增和过表达是贲门癌较常见的分子改变，并可能通过抑制野生型p53基因功能参与贲门癌形成；有mdm2扩增及表达的贲门癌组织分化程度较高，提示预后较好。

Study of the Amplification and Protein Expression of Gene mdm2 in Cardia Gastric Carcinoma

Objective 　To detect the amplification and protein expression of gene mdm2 in cardia gastric carcinoma and investigate their pathological clinical value. Methods 　Gene amplifications were detected by differential Polymerase Chain Reaction (dPCR) and protein expressions were screened by flow cytometry (FCM) and immunohistochemist ry ( IHC) . Results 　Mdm2 amplifications were found in 7 of 38 case (18. 42 %) . The values ( FI) of mdm2 expression detected by FCM were 1. 45 ±0. 34 and 1. 00 ±0. 13 in cardia gastric carcinoma and normal cardia gastric mucosa respectively ( P < 0. 01) . The positive rate of immunohistochemical staining for mdm2 protein were 64. 86 % and 0. 00 % in cardia gastric carcinoma and normal cardia gast ric mucosa respectively ( P < 0. 01) . Positive cases of mdm2 gene amplification and expression in higher grade group was higher than that in the lower grade group (33. 30 % VS 5. 00 % ,80. 00 % VS 47. 06 % , P < 0. 05) . Conclusion 　Mdm2 gene amplification and expression play an active role in cardia gast ric oncogenesis. The detection of these alternations may be helpful to assess the prognosis of cardia gastric carcinoma.