Frame M C, Freshney R I, Vaughan P F, Graham D I, Shaw R
Br J Cancer. 1984 Mar;49(3):269-80. doi: 10.1038/bjc.1984.44.
The phenotypic expression of cells derived from human anaplastic astrocytomas, rat glioma, normal human adult and foetal brain tissue have been examined for differentiated and malignancy-associated properties. Glial fibrillary acidic protein (GFAP), high affinity glutamate and gamma-amino butyric acid (GABA) uptake and glutamine synthetase were used as indicators of astroglial differentiation. Plasminogen activator and tumour angiogenesis factor were the malignancy-associated markers. The normal adult brain-derived lines showed some differentiated astroglial features and expressed low levels of the malignancy-associated properties. The foetal cultures contained highly differentiated astroglia while the glioma lines showed considerable phenotypic heterogeneity from highly differentiated to undifferentiated. The least differentiated glioma cells exhibited the highest plasminogen activator activities. The density-dependent control of phenotypic expression was also investigated. High affinity GABA uptake, and GFAP in rat C6 glioma cultures, increased with increasing monolayer cell density, events probably mediated by an increase in the formation of cell-cell contacts at confluence. Plasminogen activator activity decreased with increasing cell density.
对源自人间变性星形细胞瘤、大鼠神经胶质瘤、正常成人及胎儿脑组织的细胞的表型表达进行了检测，以了解其分化及与恶性肿瘤相关的特性。胶质纤维酸性蛋白（GFAP）、高亲和力谷氨酸和γ-氨基丁酸（GABA）摄取以及谷氨酰胺合成酶被用作星形胶质细胞分化的指标。纤溶酶原激活物和肿瘤血管生成因子是与恶性肿瘤相关的标志物。源自正常成人大脑的细胞系表现出一些分化的星形胶质细胞特征，并表达低水平的与恶性肿瘤相关的特性。胎儿培养物中含有高度分化的星形胶质细胞，而神经胶质瘤细胞系则表现出从高度分化到未分化的显著表型异质性。分化程度最低的神经胶质瘤细胞表现出最高的纤溶酶原激活物活性。还研究了表型表达的密度依赖性控制。在大鼠C6神经胶质瘤培养物中，高亲和力GABA摄取和GFAP随着单层细胞密度的增加而增加，这些事件可能是由汇合时细胞间接触形成的增加介导的。纤溶酶原激活物活性随着细胞密度的增加而降低。
