人脑胶质瘤的表皮生长因子基因及蛋白表达

Gene Expression of Epidermal Growth Factor in Human Gliomas

国内首次报道采用Northern、斑点杂交和免疫组化的方法检测了50例胶质瘤、4个恶性胶质瘤体外细胞系和7例正常脑组织表皮生长因子(EGF)的表达水平。结果显示,上述组织或细胞都可表达5.0 kb的EGF mRNA片断,高恶度胶质瘤较低恶度胶质瘤和正常脑组织EGFmRNA表达水平增高,低恶度胶质瘤与正常脑组织的表达无显著差异。在50例胶质瘤中29例(58％)EGFmRNA过表达,其中多见于恶性胶质瘤。采用免疫组化检测胶质瘤ihEGF表达发现,随胶质瘤恶性程度增加,EGF阳性细胞数及着色强度亦随之增加,EGFmRNA表达与ih EGF表达及肿瘤的分级呈正相关。提示胶质瘤可以合成EGF,在胶质瘤的发生发展过程中,EGF参与或促进了其恶性进展。

EGF mRNA levels in various grade of gliomas,malignant human glioma cell lines and normal brain tissues were examined by Northern blot and dot blot,and relative expression of a 5.0kb transcript in all tissues and cell lines with different levels were found. The EGF mRNA levels in malignant glioma were considerably higher than those in low grade gliomas and normal brains,but no significant differences were observed between low grade gliomas and normal brains. The EGF mRNA overexpression was found in 29 cases out of 50 gliomas(58% ) ,most of which occurred in high grade gliomas. EGF mRNA expression was positively correlated with tumor grade and ih EGF level. There was a similar result in immunohistoche-mical study on immunoreactive human EGF(ih EGF). Not only was the number of positive cells,but the EGF staining was also different in various grade of gliomas. Both the number and the staining intensity of the EGF positive cells increased as the tumor grade rose. The results of the present study suggested that EGF can be synthesized in human gliomas. It might participate or promote the malignant transforming process of gliomas.