应用激光共聚焦显微术检测脑星形细胞瘤中EphrinB2及EphB4蛋白的表达

背景与目的:EphrinB2是一种新型促血管生成因子。EphrinB2与其受体EphB4可表达于多种肿瘤细胞,并与肿瘤发生及血管生成有关。本研究旨在了解EphrinB2及EphB4蛋白在脑星形细胞瘤中的表达规律,并初步探讨其可能意义。方法:利用双标免疫荧光分别检测EphB4/EphrinB2蛋白与胶质纤维酸性蛋白(glialfibrilaryacidprotein,GFAP)或CD34蛋白在35例脑星形细胞瘤新鲜标本及人脑胶质瘤细胞系CHG-5、SHG-44中的共表达,以LeicaSP2激光共聚焦显微镜观察、摄像并分析。结果:EphB4或EphrinB2蛋白与CD34蛋白可在部分间质血管内共表达,定位于血管内皮细胞。在肿瘤细胞及两种细胞系,亦可见EphB4或EphrinB2蛋白与GFAP的共表达。在分化程度较低的SHG-44细胞中,EphB4或EphrinB2平均荧光强度分别为72.48±33.78和96.80±36.98,均强于相应分化较好的CHG-5细胞(56.7±21.7和53.6±18.8),而CHG-5细胞GFAP绿色荧光强度(47.5±16.7)较SHG-44细胞(22.3±15.3)则明显增强。结论:EphB4/EphrinB2蛋白表达可能与肿瘤细胞的分化程度有关。

Detecting protein expression of EphrinB2 ligand and its receptor EphB4 in astrocytoma using confocal laser scanning microscopy

BACKGROUND & OBJECTIVE: EphrinB2 is a novel angiogenic factor. EphrinB2 and its receptor EphB4 express in several kinds of tumor cells,and correlate with tumorigenesis and neoangiogenesis. This study was designed to explore the characteristics of EphB4 and EphrinB2 protein expression in astrocytomas. METHODS: Double labelling immunofluorescence was used to detect co-expression of EphB4/EphrinB2 with glial fibrilary acid protein (GFAP)or CD34 protein in 35 fresh glioma specimens, and 2 kinds of human glioma cell lines (CHG-5,and SHG-44). RESULTS: EphB4/EphrinB2 and CD34 proteins co-expressed in some tumor stromal microvessels, and mainly localizing in endothelial cells. Co-expression of EphB4/EphrinB2 and GFAP proteins was also noticed in tumor cells,and 2 glioma cell lines. In poorly-differentiated SHG-44 cells, the average fluorescence intensity of EphB4 was 72.48+/-33.78,and that of EphrinB2 was 96.80+/-36.98, both higher than those in well-differentiated CHG-5 cells (56.7+/-21.7, and 53.6+/-18.8). But the green fluorescence intensity of GFAP in SHG-44 cells was 22.3+/-15.3, while in CHG-5 cells was 47.5+/-16.7. CONCLUSION: Expressions of EphB4 and EphrinB2 proteins may be related to differentiation degree of tumor cells.