摘要目的 探讨脑肿瘤干细胞(BTSC)标记物CD133、Nestin和血管内皮细胞标记物CD31在脑胶质瘤中的表达.方法 (1)按照世界卫生组织(WHO)2000年的神经系统肿瘤分类分级标准所有标本分为Ⅱ级18例,Ⅲ级23例,Ⅳ级24例,采用免疫组织化学SP法检测CD133和Nestin在65例胶质瘤组织中的表达.(2)采用免疫荧光双染法检测CD133/CD31、Nestin/CD31和CD133/Nestin共表达情况.计算CD133~+肿瘤干细胞、CD133~+血管、Nestin~+肿瘤干细胞和Nestin~+血管所占的百分率,并进行统计学分析.结果 CD133~+肿瘤干细胞或Nestin~+肿瘤干细胞在各级别胶质瘤中均有表达,并且均可表达于血管内皮细胞.低级别组中,在CD133~+肿瘤干细胞或Nestin~+肿瘤干细胞分布的区域可见CD133~+血管或Nestin~+血管分布较少.在高级别组中,该区域则有丰富的CD133~+血管或Nestin~+血管分布,同时可见肿瘤干细胞包绕着血管生长.并且,CD133~+细胞或Nestin~+细胞的百分比与CD133~+血管(r=0.945,P<0.01)或Nestin~+血管(r=0.727,P<0.01)的表达呈正相关.免疫荧光双染可见,CD133~+细胞或Nestin~+细胞均聚集于CD31~+血管周围,并且,CD133~+/CD31~+、Nestin~+/CD31~+细胞共表达于血管内皮细胞.结论 在脑胶质瘤组织中,血管内皮细胞可表达肿瘤干细胞的标记物,因此认为,肿瘤内微血管可能来源于肿瘤干细胞的分化,并且肿瘤干细胞聚集于微血管周围生长呈巢状分布.随着肿瘤病理级别的升高,CD133~+肿瘤干细胞或Nestin~+肿瘤干细胞的百分比与CD133~+血管或Nestin~+血管的表达呈正相关.

abstractsObjective To investigate the expressions of putative brain tumor stem cell (BTSC) marker CD133, Nestin and blood vessel endothelial cell marker CD31 in 65 cases of formalin fixed paraffin embedded gliomas. The relationship of BTSC distribution with micro-blood vessels was analyzed using morphometry. Methods (1) The expression levels of Nestin and CD133 proteins were detected using SABC immunohistochemical analysis. Then we calculated the percentage of CD133~+ cells, CD133~+ blood vessels,Nestin~+ cells and Nestin~+ blood vessels among 65 tumors, grade Ⅱ(n=18), grade Ⅲ(n=23) and grade Ⅳ (n=24), according to WHO 2000 classification of nervous system tumors. (2) Double immunofluorescence staining was used to detect the co-expressions of CD133/CD31, CD133/Nestin and Nestin/CD31. Then the correlation of two different marked cells with the corresponding positive vascular endothelial cells were determined. Results CD133~+cells and Nestin~+cells could be observed in all glioma tissues. Furthermore they could also be observed expressing in the endothelial cells. In low-grade group,there were fewer CD133~+ blood vessels or Nestin~+blood vessels in the regions which CD133~+ cells or Nestin~+ cells distributed compared with the high-grade group. The CD133~+/CD31~+ and Nestin~+/CD31~+ cells could be found co-expressed in the endothelial cells by using double immunofluorescence staining.Positive correlation was observed between the CD133~+cells and CD133~+ blood vessels(r=0.945, P < 0.01). It was similar to the correlation between the Nestin~+ blood vessels and Nestin~+ cells (r=0. 727,P<0.01). Conclusion In gliomas, the endothelial cells express brain tumor stem cells markers.Therefore the capillaries in gliomas may come from the differentiation of BTSCs. And the BTSCs are accumulated around the capillaries. Along with the rank of tumor grades, positive correlation is observed between CD133~+ cells or Nestin~+ cells with the corresponding blood vessels.