Oligomeric collagen XVIII-derived endostatin requires cell surface heparan sulfate in order to induce morphological changes in endothelial and epithelial cell lines in vitro. - Clamp, A.R.; Blackhall, F.H.; Henrioud, A.; Jayson, G.C.; Javaherian, K.; Esko, J.; Gallagher, J.T.; Merry, C.L.R. (International Journal of Experimental Pathology, 2004)