Angiostatin

Angiostatin is a human protein. It is a natural angiogenesisinhibitor (i.e. it blocks the growth of new blood vessels), and it is currently underlying clinical trialsfor its use in anticancer therapy[1].

Structure

Angiostatin is a 57 kDa fragment of a larger protein, plasmin(itself a fragment of plasminogen) enclosing three to five contiguous Kringlemodules. Each module contains two small beta sheetsand three disulfide bonds.

Generation

Angiostatin is produced by autoproteolyticcleavage of plasminogen, involving extracellular disulfide bond reductionby phosphoglycerate kinase.

Biological activity

Angiostatin is known to bind a lot of proteins, especially to angiomotinand endothelial cell surface ATP synthasebut also integrins, annexinII, C-met receptor, NG2-proteoglycans, tissue-type plasminogen activator, chondroitin sulfate proteoglycans, and CD26. Also smaller fragments of angiostatin has been shown to bind several other proteins. There is still considerable uncertainty on its mechanism of action, but it seems to involve for example inhibition of endothelial cell migration, proliferationand induction of apoptosis.

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It uses material from the http://en.wikipedia.org/wiki/Angiostatin Wikipedia article Angiostatin.