Mammalian heparanase: Gene cloning, expression and function in tumor progression and metastasis
Mammalian heparanase: Gene cloning, expression and function in tumor progression and metastasis
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DOI：
10.1038/10518
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发表时间：
1999-07-01
期刊：
影响因子：
82.9
通讯作者：
Pecker, I
中科院分区：
文献类型：
--
作者：
Vlodavsky, I;Friedmann, Y;Pecker, I
硫酸肝素蛋白聚糖与许多细胞外基质成分、生长因子和酶相互作用。内糖苷型肝素酶裂解对硫酸肝素的降解影响多种生物过程。我们从人肝癌和胎盘中纯化了一个50 kda的肝素酶，并克隆了该酶的cDNA和编码基因。克隆的cDNA在昆虫和哺乳动物细胞中表达得到65 kda和50 kda的重组肝素酶蛋白。50kda酶是一种n端加工酶，活性至少是65kda酶的100倍。肝素酶mRNA和蛋白在乳腺癌、结肠癌和肝癌的转移细胞系和标本中优先表达。转染肝素酶cDNA的低转移性小鼠t -淋巴瘤和黑色素瘤细胞在体内获得了高度转移的表型，反映在大量的肝脏和肺部定植。据我们所知，这是第一个克隆的哺乳动物肝素酶，并为其在肿瘤转移中的作用提供了直接证据。肝素酶基因的克隆使开发特异性分子探针能够用于癌症转移和自身免疫性疾病的早期检测和治疗。
Heparan sulfate proteoglycans interact with many extracellular matrix constituents, growth factors and enzymes. Degradation of heparan sulfate by endoglycosidic heparanase cleavage affects a variety of biological processes. We have purified a 50-kDa heparanase from human hepatoma and placenta, and now report cloning of the cDNA and gene encoding this enzyme. Expression of the cloned cDNA in insect and mammalian cells yielded 65-kDa and 50-kDa recombinant heparanase proteins. The 50-kDa enzyme represents an N-terminally processed enzyme, at least 100-fold more active than the 65-kDa form. The heparanase mRNA and protein are preferentially expressed in metastatic cell lines and specimens of human breast, colon and liver carcinomas. Low metastatic murine T-lymphoma and melanoma cells transfected with the heparanase cDNA acquired a highly metastatic phenotype in vivo, reflected by a massive liver and lung colonization. This represents the first cloned mammalian heparanase, to our knowledge, and provides direct evidence for its role in tumor metastasis. Cloning of the heparanase gene enables the development of specific molecular probes for early detection and treatment of cancer metastasis and autoimmune disorders.