Novel inhibitors of angiogenesis and tumor growth

Abstract

This invention provides for polypeptides that have surprising anti-angiogenic activity. These peptides are derived from Saposin B, a previously known protein involved in the hydrolysis of sphingolipids. In addition, methods of treating mammals with these anti-angiogenic polypeptides are provided, as well as the pharmaceutical compositions used to treat. Furthermore, the polypeptides of this invention can be used in fusion proteins, wherein the fusion proteins also comprise cell targeting or cytotoxic moieties. Also provided is the receptor to which these polypeptides bind.

1 - 23 . (canceled) 
     
     
         24 . An isolated protein, wherein said protein specifically binds to Saposin B and is found on the surface of cells selected from the group consisting of KS Y-1, SLK and HUVEC. 
     
     
         25 . The isolated protein of  claim 24 , wherein said protein is recombinantly expressed. 
     
     
         26 . An antibody that is specifically reactive with the isolated polypeptide of claim  7 . 
     
     
         27 . The antibody of  claim 26 , wherein said monoclonal antibody is a monoclonal antibody. 
     
     
         28 . The antibody of  claim 26 , wherein said antibody is a single chain antibody. 
     
     
         29 - 52 . (canceled)