NOVEL METALLOPROTEINASE INHIBITORS--ROLE IN TUMOR INVASION AND METASTASIS

我们分离并鉴定了一个新的 金属蛋白酶组织抑制剂家族（TIMP家族）成员 我们称之为TIMP-2。 最近的研究表明， 迄今为止所研究的分泌72 kDa IV型胶原酶的细胞 分泌这种酶作为TIMP-2的复合物。 大多数大于 发现95%的分泌型72 kDa明胶酶以复合形式存在，因为大多数细胞 测试分泌游离TIMP-2的2-4倍。 我们的研究表明，TIMP- 2转录本离子的调节独立于TIMP-1和72 kDa的 IV型胶原酶。 我们还证明了TIMP-2是 抗血管生成。 这种影响的机制是双重的;通过 抑制内皮细胞增殖和阻断内皮细胞 细胞介导的基质蛋白水解。 TIMP-2抑制肿瘤细胞侵袭 通过体外重建的基底膜，这种抑制剂 显示红细胞增强活性（EPA）。 TIMP-2抑制 出血性卒中血脑屏障蛋白水解开放 模型 已获得TIMP-2基因组克隆，并进行部分测序。 在该基因的3'端发现了两个内含子。 该基因似乎是 单拷贝，定位于人染色体17 q25。 我们已经检查了TIMP-2蛋白的结构，并定位了TIMP-2的表达。 金属蛋白酶抑制结构域的N-末端的一半分子。 进一步亚定位已尝试使用合成肽 方法以及用于X射线衍射和NMR的蛋白质结晶， 谱

We have isolated and characterized the complete primary structure of a new member of the tissue inhibitor of metalloproteinase family (TIMP family) which we refer to as TIMP-2. Recent studies have shown that all cells studied to date which secrete the 72 kDa type IV collagenase enzyme secrete this enzyme as a complex with TIMP-2. The majority greater than 95% of secreted 72 kDa gelatinase is found in complexed form as most cells tested secrete 2-4 fold as free TIMP-2. Our studies have shown that TIMP- 2 transcript ion is regulated independently of both TIMP-1 and the 72 kDa type IV collagenase enzyme. We have also demonstrated that TIMP-2 is anti-angiogenic. The mechanism for this effect is two fold; through inhibition of endothelial cell proliferation and blocking endothelial cell-mediated matrix proteolysis. TIMP-2 inhibits tumor cell invasion through reconstituted basement membranes in vitro, and this inhibitor demonstrates erythroid potentiating activity (EPA) . TIMP-2 inhibits proteolytic opening of the blood brain barrier in hemorrhagic stroke models. TIMP-2 genomic clones have been obtained and partial sequencing has identified two introns in the 3' end of the gene. The gene appears to be single copy and is localized on human chromosome 17q25. We have examined the TIMP-2 protein structure and have localized the metalloprotease inhibitory domain to the N-terminal half of the molecule. Further sublocalization has been attempted using a synthetic peptide approach as well as protein crystallization for x-ray diffraction and NMR- spectroscopy.