PI3K通路蛋白在难治性癫痫相关脑皮质发育畸形病灶中的表达

摘要

目的 探讨几种PI3K相关通路蛋白在难治性癫痫相关皮质发育畸形(MCD)患者脑组织内的表达情况.方法 选用2005至2008年因难治性癫痫在宣武医院行手术治疗,病理证实为MCD的43例患者脑组织标本作为病例组,包括局灶性皮质发育不良(FCD)ⅡA型、ⅡB型各11例,结节性硬化综合征(TSC)10例,神经节细胞胶质瘤11例;另选12例作为对照组.将所选病例划分为7个研究组,采用免疫组织化学EnVision二步法染色观察并比较针对TSC1、TSC2、p-mTOR、p-4E-BP1、p-p70S6K和p-S6等6种蛋白的抗体在各组的表达情况.用图像分析软件测量累积吸光度和阳性细胞面积并应用SPSS 16.0统计分析软件对各组测量值进行统计学分析.结果 TSC1和TSC2的表达部位相似,在形态异常神经元区域、气球样细胞区域、巨细胞区域、神经节细胞胶质瘤病变以及正常神经元的胞质内能观察到程度不等的细颗粒状表达.TSC1在正常神经元的表达要明显强于其他各组(P＜0.01),而TSC2在巨细胞内表达最弱(P＜0.01).p-mTOR主要表达于巨细胞内,在对照组相对正常的脑组织也可见表达,两者间的差异具有统计学意义(P＜0.01).p-4E-BP1可以在气球样细胞、巨细胞及神经节细胞胶质瘤内观察到中度阳性的表达,巨细胞着色程度强于气球样细胞,而二者的表达比神经节细胞胶质瘤弱,两两比较差异具有统计学意义(P＜0.0l).p-p70S6K主要于巨细胞内可以观察到弱至中度阳性表达,气球样细胞内偶可有弱阳性表达,两者差异具有统计学意义(P＜0.0l).p-S6明显表达于各组病例内的异常细胞成分.结论 PI3K通路至少部分参与了MCD的发生,并可能发挥了重要作用.%Objective To investigate the expression of TSC1,TSC2,p-mTOR,p-4E-BP1,p-p70S6K and p-S6 in refractory epilepsy associated malformation of cortical development (MCD) tissues.Methods A total of 43 cases of refractory epilepsy were involved in the study,and all the patients were treated in Xuanwu Hospital during 2005 -2008,including focal cortical dysplasia type Ⅱ a ( 11 cases) and type Ⅱb (11 cases),tuberous sclerosis complex (10 cases) and ganalioglioma (11 cases),and other 12 cases were used as control These cases were divided into 7 study groups and immunohistochemical EnVision method was used.To detect the location and intensity of TSC1,TSC2,p-mTOR,p-4E-BP1,p-p70S6K and p-S6 expression in every group.Then the Image-Pro Plus 6.0 image processing and analysis software were used to measure the number,area,integrating absorbance ( IA ) of positive cells in every samples.The statistical software SPSS 16.0 was used to analyze the data.Results The immunolocalization of TSC1 and TSC2 was similar.It could be observed the expression of various levels in the cytoplasm of dysmorphic neurons,balloon cells,giant cells,ganglioglioma cells and normal neurons.TSC1 staining in normal neurons was more notably than others but TSC2 staining in giant cells was weaker than other samples.p-mTOR mainly presented in giant cells,which could also be observed in astrocyte.P-4E-BP1 presented in the cytoplasm and nuclear membrane of balloon cells,giant cells and ganglioglioma cells,the staining of giant cells was stronger than balloon cells,but their staining were weaker than ganglioglioma cells.P-p70S6K mainly expressed in giant cells and less commonly presented in balloon cells.P-S6 typically presented in all abnormal glioneuronal cells and it nearly did not present in the normal neurons of N-CTX group.Conclusions PI3K pathway,at least in part,involves in the occurrence of MCD,and may play an important role in the pathogenesis.