Del Maestro R F, Vaithilingam I S, McDonald W
Department of Clinical Neurological Sciences, Victoria Hospital Research Institute, University of Western Ontario, London, Canada.
J Neurooncol. 1995;24(1):75-81. doi: 10.1007/BF01052662.
The key event associated with the initiation of angiogenesis is the localized degradation of the vascular basement membrane. Because of its complex structure, any remodelling and/or modification of the basement membrane must involve the co-ordinated function of a number of different enzyme systems. Type IV collagen is a major protein component (60-90%) of the basement membrane and its degradation is crucial to the initiation of angiogenesis. This study has focused on the mechanisms by which C6 astrocytoma cells degrade human type IV collagen. C6 astrocytoma cells use components of two major degradative pathways to degrade collagen type IV. The major matrix metalloproteinase identified is the activated form (68-KDa) of gelatinase A (72-KDa matrix metalloproteinase) and a serine sensitive 1000-KDa collagenase type IV degrading activity which appears to have the characteristics of a novel extracellular proteasome.
与血管生成起始相关的关键事件是血管基底膜的局部降解。由于其结构复杂，基底膜的任何重塑和/或修饰都必须涉及多种不同酶系统的协同作用。IV型胶原是基底膜的主要蛋白质成分（60 - 90%），其降解对于血管生成的起始至关重要。本研究聚焦于C6星形细胞瘤细胞降解人IV型胶原的机制。C6星形细胞瘤细胞利用两条主要降解途径的成分来降解IV型胶原。鉴定出的主要基质金属蛋白酶是明胶酶A（72 kDa基质金属蛋白酶）的活化形式（68 kDa）以及一种对丝氨酸敏感的1000 kDa IV型胶原酶降解活性，其似乎具有新型细胞外蛋白酶体的特征。
