title: A SEMA3E mutant resistant to cleavage by furins (UNCL-SEMA3E) inhibits choroidal neovascularization.
abstract: Abnormal subretinal choroidal neovascularization (CNV) is a major cause of blindness in exudative age-related macular degeneration (AMD). Current anti-angiogenic treatments by VEGF sequestering agents have been successful, but a significant proportion of patients do not respond well to these treatments, and the response of others diminishes over time, suggesting that additional anti-angiogenic agents that function by separate mechanisms may be of use to such patients. We have previously found that a point mutated form of semaphorin-3E resistant to cleavage by furin like pro-protein convertases (UNCL-Sema3E) displays potent anti-angiogenic properties. We therefore determined if UNCL-Sema3E has potential as an inhibitor of CNV formation. We chose to study UNCL-Sema3E rather than wild type sema3E because unlike full length sema3E, the major p61-Sema3E peptide that is produced by cleavage of sema3E with furin like pro-protein convertases activates signal transduction mediated by the ErbB2 receptor and can promote tumor metastasis in addition to its anti-angiogenic activity. UNCL-Sema3E inhibited efficiently vascular endothelial growth factor-A (VEGF), platelet derived growth factor (PDGF) and basic fibroblast growth factor (bFGF) signaling in human umbilical vein derived endothelial cells (HUVEC) and to a lesser extent hepatocyte growth factor (HGF) signal transduction. CNV that was induced in the eyes of C57 black mice by laser photocoagulation was inhibited by 65% (P < 0.01) following a single bolus intra-vitreal injection of 5 μg UNCL-Sema3E. This inhibitory effect was similar to the inhibition produced by a single bolus intra-vitreal injection of 5 μg aflibercept. A similar inhibition of CNV was observed following the injection of UNCL-Sema3E into the eyes of Long-Evans rats. However, a higher dose of UNCL-Sema3E (125 μg), partially due to the larger volume of the vitreous cavity of rats, was required to achieve maximal inhibition of CNV. Injection of UNCL-Sema3E into eyes of healthy mice did not have any adverse effect on retinal function as assessed by optic kinetic reflex (OKR) or by electroretinogram (ERG) assays nor did UNCL-Sema3E injection affect the structure of the retina as determined using histology. To conclude, our results suggest that UNCL-Sema3E may be useful for the treatment of exudative AMD, which does not respond well to conventional anti-VEGF therapy.
authors.affiliation: Cancer Research and Vascular Biology Center, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel.
authors.forename: Shira
authors.initials: S
authors.lastname: Toledano
authors.affiliation: Second Hospital of Jilin University, Changchun, Jilin Province, 130041, PR China; Department of Ophthalmology and Visual Sciences, University of Louisville, KY, USA.
authors.forename: Huayi
authors.initials: H
authors.lastname: Lu
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Louisville, KY, USA.
authors.forename: Agustina
authors.initials: A
authors.lastname: Palacio
authors.affiliation: Cancer Research and Vascular Biology Center, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel.
authors.forename: Boaz
authors.initials: B
authors.lastname: Kigel
authors.affiliation: Cancer Research and Vascular Biology Center, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel.
authors.forename: Ofra
authors.initials: O
authors.lastname: Kessler
authors.affiliation: Department of Ophthalmology, Rambam Medical Center, Haifa, Israel.
authors.forename: Gilad
authors.initials: G
authors.lastname: Allon
authors.affiliation: Department of Ophthalmology, Rambam Medical Center, Haifa, Israel. Electronic address: yorehb@gmail.com.
authors.forename: Yoreh
authors.initials: Y
authors.lastname: Barak
authors.affiliation: Cancer Research and Vascular Biology Center, The Bruce Rappaport Faculty of Medicine, Technion, Israel Institute of Technology, Haifa, Israel. Electronic address: gera@tx.technion.ac.il.
authors.forename: Gera
authors.initials: G
authors.lastname: Neufeld
authors.affiliation: Department of Ophthalmology and Visual Sciences, University of Louisville, KY, USA; Department of Ophthalmology and Visual Sciences, University of Massachusetts School of Medicine, USA. Electronic address: s.schaal@umassmed.edu.
authors.forename: Shlomit
authors.initials: S
authors.lastname: Schaal
mesh_terms: D000818:Animals; D020256:Choroidal Neovascularization / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D003598:Cytoskeletal Proteins; D004195:Disease Models, Animal; D006023:Glycoproteins / Q000008:administration & dosage* / Q000235:genetics; D006801:Humans; D058449:Intravitreal Injections; D008565:Membrane Proteins / Q000008:administration & dosage* / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D017354:Point Mutation; D016601:RNA-Binding Proteins / Q000008:administration & dosage* / Q000235:genetics; D051381:Rats; D020318:Rats, Long-Evans; D039961:Semaphorins
chemical_list: D003598:Cytoskeletal Proteins; D006023:Glycoproteins; D008565:Membrane Proteins; D016601:RNA-Binding Proteins; C111150:Sema3e protein, mouse; D039961:Semaphorins; C416052:Unc50 protein, rat
keywords: Age related macular degeneration; Angiogenesis; Choroidal neovascularization; Semaphorin