人脑星形细胞肿瘤CD133和巢蛋白阳性细胞的分布特征

Distribution characteristics of CD133-positive and nestin-positive cells in human astrocytoma

目的探讨CDl33和巢蛋白阳性细胞在人脑星形细胞肿瘤中的分布特征。方法采集不同级别星形细胞肿瘤标本31例,免疫组织化学染色检测其胶质瘤干细胞标志物CD133和巢蛋白表达水平,光学显微镜下观察CD133和巢蛋白阳性细胞在不同级别星形细胞肿瘤中的分布特征。结果不同级别肿瘤之间和同一肿瘤不同区域之间CD133阳性细胞的分布呈现极大变异性,低级别星形细胞肿瘤完全不表达或仅单个细胞表达,高级别星形细胞肿瘤成簇表达,其特异性分布特征为CDl33阳性细胞围绕微血管分布,单个细胞贴附于血管外壁,在肿瘤周围水肿区域亦可呈散在分布而不贴附于血管外壁;簇状或:巢状分布的CD133阳性细胞均位于近血管区域,CD133阳性细胞形态亦不尽一致,无论是新生发芽的肿瘤性血管内皮细胞还是成熟的血管内皮细胞均不表达CD133。巢蛋白阳性细胞在不同级别肿瘤之间和同一肿瘤不同区域之间具有与CD133阳性细胞相似的分布特征,但新生发芽的肿瘤性血管内皮细胞巢蛋白表达阳性;变性肿瘤中巢蛋白阳性细胞可呈"开屏状"分布,而CD133阳性细胞未见类似分布。结论 CD133和巢蛋白阳性细胞在人脑星形细胞肿瘤中呈现近微血管分布和富集于肿瘤周围水肿区域的分布特征,新生发芽的肿瘤性血管内皮细胞巢蛋白表达阳性。

Objective To explore the distribution characteristics of CD133-positive and nestinpositive cells in human astrocytoma. Methods Thirty-one specimens of human astrocytoma with different World Health Organization （WHO） grades were collected. Immunohistochemistry was used to detect the expressions of glioma stem cells （GSCs） markers： CD133 and nestin. Light microscope was applied to analyse the distribution characteristics of CD133- positive and nestinpositive ceils of astrocytoma in different WHO grades. Results 1） The distribution of CD133-positive ceils varied significantly in human astrocytoma of different WHO grades and in different areas of the same tumor, and the distribution characteristics were specific. No positive cells or single- positive cells scattered in astrocytoma of low grades while positive cells in cluster were found in astrocytoma of high grades. The positive cells generally distributed around microvessels, and the single-positive cells usually adhered to external wall of blood vessels. The single-positive ceils also scattered in the peritumoral edema areas, but did not adhere to the external wall of blood vessels. The cluster-like or nest-like distribution of single-positive cells were generally near to the blood vessel areas. The morphology of CD133-positive cells was also different. There was no expression of CD133 in newly germinated tumor vascular endothelial cells or in mature vascular endothelial cells. 2） The distribution of nestinpositive cells in human astroeytoma of different WHO grades and in different areas of the same tumor had similar distribution characteristics as CD133- positive ceils, but nestin could be also expressed in newly germinated tumor vascular endothelial cells.Furthermore, nestin-positive cells sometimes gathered radially around blood vessels in astrocytoma, but similar distribution characteristic was not found in CD133-positive cells. Conclusion CD133-positive and nestin-positive cells in human astrocytoma distribute around microvessels and enrich in the peritumoral edema areas; furthermore, newly germinated tumor vascular endothelial cells are usually nestin-positive cells.