Smad2基因在人脑胶质瘤的表达及其临床意义

摘要

目的 探讨Smad2基因在人脑胶质瘤组织中的表达情况,与细胞增殖指数Ki-67及患者生存期的关系.方法 对80例人脑胶质瘤组织标本,用免疫组化SP法检测Smad2、Ki -67的蛋白表达,逆转录聚合酶链反应法( RT - PCR)测定Smad2 mRNA的转录水平.Smad2蛋白表达情况与患者生存期的关系用Kaplan -Meier生存曲线表示,并采用log - rank方法分析.结果 (1) Smad2蛋白在高级别胶质瘤(Ⅲ级和Ⅳ级)中表达水平较低级别胶质瘤(Ⅱ级)明显增高(P ＜0.001).(2)Smad2 mRNA在高级别胶质瘤(Ⅲ级和Ⅳ级)中转录水平较低级别胶质瘤(Ⅱ级)增高(P＜0.05).(3)Smad2蛋白阳性表达与Ki -67阳性表达呈正相关(r=0.812,P＜0.001).(4)将所有患者分为Smad2高表达组和低表达组,两组间生存率差异有统计学意义(P＜0.05).结论 Smad2的转录和蛋白表达水平在恶性胶质瘤中显著增高,检测Smad2表达水平有利于脑胶质瘤的恶性程度判断及对患者预后的评估.%Objective To investigate the expressions of Smad2 gene in human gliomas,and to explore whether the expression of Smad2 associate with pathologic grading and the expression of Ki - 67.Methods The expression of Smad2 mRNA was examined by reverse transcription polymerase chain reaction ( RT - PCR) and its protein was detected by SP immunohistochemistry in 80 human glioma specimens.The results were analyzed with statistic methods.The comparison of Kapan - Meier survival curves of overall survival time according to Smad2 expression was analyzed by log - rank method.Results ( 1 ) The expression of Smad2 protein increased in high grade glioma ( Ⅲ and Ⅳ ),while it decreased in low grade glioma ( Ⅱ ) significantly ( P ＜ 0.001 ).( 2 ) The level of Smad2 mRNA transcription increased in high grade glioma,while it decreased in low grade glioma ( P ＜ 0.05).(3) The expressions of Smad2 and Ki -67 had positive correlation ( r =0.812,P ＜0.001 ).(4) According to integrated optical density of Smad2,all patients were divided into two groups,Low Smad2 and High Smad2.Overall survival time was significantly different between the two groups ( P ＜ 0.05 ).Conclusion The expression of Smad2 protein and the level of mRNA transcription increases significantly in malignant gliomas.Detecting Smad2 protein or mRNA in human glioma can be used for judging the malignancy degree and the prognosis.