p53蛋白和MDM 2 蛋白在食管鳞状细胞癌中的表达及意义

Expression of p53 and MDM 2 Protein and theirSignificance in Esophageal Carcinomas

为了探讨肿瘤抑制基因ｐ５３和癌基因ＭＤＭ２在食管鳞状细胞癌中的表达及其意义，采用免疫组织化学链菌素亲生物素蛋白过氧化物酶连接法（ＳＰ法），检测了６８例食管鳞状细胞癌中ｐ５３蛋白和ＭＤＭ２蛋白的表达，结果显示ｐ５３蛋白和ＭＤＭ２蛋白阳性率分别为６０．３％（４１／６８）和４２．６％（２９／６８），ｐ５３蛋白阳性率与食管鳞状细胞癌分级呈显著正相关（Ｐ＜０．０１），ＭＤＭ２蛋白阳性率与食管鳞状细胞癌分级呈显著负相关（Ｐ＜０．０１），并与食管鳞状细胞癌临床病理分期呈显著负相关（Ｐ＜０．０５）。在６８例食管鳞状细胞癌中，ｐ５３蛋白阳性表达者４１例，其中ｐ５３蛋白和ＭＤＭ２蛋白表达均阳性者１２例，ＭＤＭ２蛋白表达阴性者２９例；在６８例食管癌中，ＭＤＭ２蛋白阳性表达者２９例，其中ＭＤＭ２与ｐ５３蛋白均阳性者１２例，ｐ５３蛋白表达阴性者１７例，两者呈显著负相关（Ｐ＜０．０１），ｐ５３蛋白和ＭＤＭ２蛋白表达均阴性者１０例。可以认为ｐ５３蛋白和ＭＤＭ２蛋白表达可作为食管鳞状细胞癌病理分级参考指标之一，ＭＤＭ２蛋白表达还可作为食管鳞状细胞癌临床病理分期的参考指标之一，并间接证明ＭＤＭ２蛋白对ｐ５３蛋白表达具有负性调节作用。

The expression of p53 and MDM 2 proteins were detected by immunohistochemical method in 68 esophageal squamous cell carcinomas.The positive rates of p53 and MDM 2 were 60.3%(41/68) and 42.6%(29/68) respectively.p53 positive rate increased with the progression of pathological grade (P<0.01).while MDM 2 positive rate decreased with pathological grade (P<0.01) and clinical pathological stage (P<0.05).In 68 cases of esophageal carcinomas,41 cases were p53 positive,12 cases of them were p53 and MDM 2 double positive,29 of p53positive specimens did not stain for MDM 2,there was thus an inverse relationship between the expression of p53 and MDM 2 protein (P<0.01).In 68 cases of esophageal carcinomas,29 cases showed MDM 2 positive staining,12 cases of them were p53 and MDM 2 double positives,17 of MDM 2 positive specimens did not stain for p53.The authors suggest that the presence or absence of expression of p53 and MDM 2 protein is one of the reference indicators for pathological grading,and also MDM 2 protein is one of the reference indicators for clinical pathological stage in esophageal squamous cell carcinoma,the results indirectly support the theory that p53 expression is negatively regulated by the functional MDM 2 protein.