title: The marine-derived oligosaccharide sulfate (MdOS), a novel multiple tyrosine kinase inhibitor, combats tumor angiogenesis both in vitro and in vivo.
abstract: Despite the emerging success of multi-targeted protein tyrosine kinase (PTK) inhibitors in cancer therapy, significant side effects and resistance concerns seems to be avoided unlikely. The aim of the present study was to identify novel multi-targeting PTK inhibitors. The kinase enzymatic activities were measured by enzyme-linked immunosorbent assay (ELISA). The antiproliferative activities in human microvascular endothelial cells (HMECs) were evaluated by sulforhodamine (SRB) assay. The phosphorylation of kinases and their downstream molecules was probed by western blot analysis. The binding mode between MdOS and PTKs was profiled by surface plasmon resonance (SPR) approach and molecular simulation. Tube formation assay, rat aortic ring method and chicken chorioallantoic membrane assay were combined to illustrate the in vitro and in vivo anti-angiogenic effects. Results indicated that MdOS, a novel marine-derived oligosaccharide sulfate, exhibited a broad-spectrum PTK inhibitory action. At an enzymatic level, MdOS inhibited HER2, EGFR, VEGFR, PDGFR, c-Kit, FGFR1 and c-Src, with little impact on FGFR2. In cellular settings, MdOS inhibited phosphorylation of PTKs, exemplified by HER2, EGFR and VEGFR2, and downstream molecules of Erk1/2 and AKT. Further studies demonstrated that MdOS acted as an ATP-competitive inhibitor via directly binding to the residues of entrance rather than those of the ATP-binding pocket. Furthermore, MdOS inhibited proliferation and tube formation of HMECs, arrested microvessel outgrowth of rat aortic rings and hindered the neovascularization of chick allantoic membrane. Taken together, results presented here indicated that MdOS exhibited anti-angiogenic activity in a PTK-dependent manner and make it a promising agent for further evaluation in PTK-associated cancer therapy.
authors.affiliation: Division of Anti-Tumor Pharmacology, State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
authors.forename: Jingui
authors.initials: J
authors.lastname: Ma
authors.forename: Xianliang
authors.initials: X
authors.lastname: Xin
authors.forename: Linghua
authors.initials: L
authors.lastname: Meng
authors.forename: Linjiang
authors.initials: L
authors.lastname: Tong
authors.forename: Liping
authors.initials: L
authors.lastname: Lin
authors.forename: Meiyu
authors.initials: M
authors.lastname: Geng
authors.forename: Jian
authors.initials: J
authors.lastname: Ding
mesh_terms: D000818:Animals; D001011:Aorta / Q000378:metabolism; D045744:Cell Line, Tumor; D002645:Chickens; D049033:Chorioallantoic Membrane / Q000378:metabolism; D004730:Endothelium, Vascular / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D008833:Microcirculation; D009369:Neoplasms / Q000188:drug therapy / Q000378:metabolism*; D009389:Neovascularization, Pathologic; D009844:Oligosaccharides / Q000737:chemistry*; D047428:Protein Kinase Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013431:Sulfates / Q000737:chemistry*
chemical_list: D009844:Oligosaccharides; D047428:Protein Kinase Inhibitors; D013431:Sulfates; D011505:Protein-Tyrosine Kinases