title: Direct and allosteric inhibition of the FGF2/HSPGs/FGFR1 ternary complex formation by an antiangiogenic, thrombospondin-1-mimic small molecule.
abstract: Fibroblast growth factors (FGFs) are recognized targets for the development of therapies against angiogenesis-driven diseases, including cancer. The formation of a ternary complex with the transmembrane tyrosine kinase receptors (FGFRs), and heparan sulphate proteoglycans (HSPGs) is required for FGF2 pro-angiogenic activity. Here by using a combination of techniques including Nuclear Magnetic Resonance, Molecular Dynamics, Surface Plasmon Resonance and cell-based binding assays we clarify the molecular mechanism of inhibition of an angiostatic small molecule, sm27, mimicking the endogenous inhibitor of angiogenesis, thrombospondin-1. NMR and MD data demonstrate that sm27 engages the heparin-binding site of FGF2 and induces long-range dynamics perturbations along FGF2/FGFR1 interface regions. The functional consequence of the inhibitor binding is an impaired FGF2 interaction with both its receptors, as demonstrated by SPR and cell-based binding assays. We propose that sm27 antiangiogenic activity is based on a twofold-direct and allosteric-mechanism, inhibiting FGF2 binding to both its receptors.
authors.affiliation: Laboratorio NMR, Istituto per lo Studio delle Macromolecole, Consiglio Nazionale delle Ricerche, Milano, Italy.
authors.forename: Katiuscia
authors.initials: K
authors.lastname: Pagano
authors.forename: Rubben
authors.initials: R
authors.lastname: Torella
authors.forename: Chiara
authors.initials: C
authors.lastname: Foglieni
authors.forename: Antonella
authors.initials: A
authors.lastname: Bugatti
authors.forename: Simona
authors.initials: S
authors.lastname: Tomaselli
authors.forename: Lucia
authors.initials: L
authors.lastname: Zetta
authors.forename: Marco
authors.initials: M
authors.lastname: Presta
authors.forename: Marco
authors.initials: M
authors.lastname: Rusnati
authors.forename: Giulia
authors.initials: G
authors.lastname: Taraboletti
authors.forename: Giorgio
authors.initials: G
authors.lastname: Colombo
authors.forename: Laura
authors.initials: L
authors.lastname: Ragona
mesh_terms: D000494:Allosteric Regulation / Q000187:drug effects; D020533:Angiogenesis Inhibitors / Q000737:chemistry / Q000494:pharmacology*; D016222:Fibroblast Growth Factor 2 / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D019812:Heparan Sulfate Proteoglycans / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D008958:Models, Molecular; D056004:Molecular Dynamics Simulation; D018716:Molecular Mimicry; D046912:Multiprotein Complexes / Q000037:antagonists & inhibitors / Q000737:chemistry; D009282:Naphthalenesulfonates / Q000737:chemistry / Q000494:pharmacology; D019906:Nuclear Magnetic Resonance, Biomolecular; D025941:Protein Interaction Mapping; D051496:Receptor, Fibroblast Growth Factor, Type 1 / Q000037:antagonists & inhibitors* / Q000737:chemistry*; D020349:Surface Plasmon Resonance; D019700:Thrombospondin 1 / Q000737:chemistry / Q000494:pharmacology
chemical_list: D020533:Angiogenesis Inhibitors; D019812:Heparan Sulfate Proteoglycans; D046912:Multiprotein Complexes; D009282:Naphthalenesulfonates; D019700:Thrombospondin 1; D016222:Fibroblast Growth Factor 2; C496348:FGFR1 protein, human; D051496:Receptor, Fibroblast Growth Factor, Type 1