title: Identification of cyclins A1, E1 and vimentin as downstream targets of heme oxygenase-1 in vascular endothelial growth factor-mediated angiogenesis.
abstract: Angiogenesis is an essential physiological process and an important factor in disease pathogenesis. However, its exploitation as a clinical target has achieved limited success and novel molecular targets are required. Although heme oxygenase-1 (HO-1) acts downstream of vascular endothelial growth factor (VEGF) to modulate angiogenesis, knowledge of the mechanisms involved remains limited. We set out identify novel HO-1 targets involved in angiogenesis. HO-1 depletion attenuated VEGF-induced human endothelial cell (EC) proliferation and tube formation. The latter response suggested a role for HO-1 in EC migration, and indeed HO-1 siRNA negatively affected directional migration of EC towards VEGF; a phenotype reversed by HO-1 over-expression. EC from Hmox1(-/-) mice behaved similarly. Microarray analysis of HO-1-depleted and control EC exposed to VEGF identified cyclins A1 and E1 as HO-1 targets. Migrating HO-1-deficient EC showed increased p27, reduced cyclin A1 and attenuated cyclin-dependent kinase 2 activity. In vivo, cyclin A1 siRNA inhibited VEGF-driven angiogenesis, a response reversed by Ad-HO-1. Proteomics identified structural protein vimentin as an additional VEGF-HO-1 target. HO-1 depletion inhibited VEGF-induced calpain activity and vimentin cleavage, while vimentin silencing attenuated HO-1-driven proliferation. Thus, vimentin and cyclins A1 and E1 represent VEGF-activated HO-1-dependent targets important for VEGF-driven angiogenesis.
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: Andrea
authors.initials: A
authors.lastname: Bauer
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: Hayley
authors.initials: H
authors.lastname: Mylroie
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: C Clare
authors.initials: CC
authors.lastname: Thornton
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: Damien
authors.initials: D
authors.lastname: Calay
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: Graeme M
authors.initials: GM
authors.lastname: Birdsey
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: Allan P
authors.initials: AP
authors.lastname: Kiprianos
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: Garrick K
authors.initials: GK
authors.lastname: Wilson
authors.affiliation: Instituto Gulbenkian de Ciência, 2780-156 Oeiras, Portugal.
authors.forename: Miguel P
authors.initials: MP
authors.lastname: Soares
authors.affiliation: King's British Heart Foundation Centre, King's College London, London, UK.
authors.forename: Xiaoke
authors.initials: X
authors.lastname: Yin
authors.affiliation: King's British Heart Foundation Centre, King's College London, London, UK.
authors.forename: Manuel
authors.initials: M
authors.lastname: Mayr
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Randi
authors.affiliation: Vascular Sciences, Imperial Centre for Translational and Experimental Medicine, National Heart and Lung Institute, Imperial College London, Hammersmith Hospital, London, UK.
authors.forename: Justin C
authors.initials: JC
authors.lastname: Mason
mesh_terms: D043925:Angiogenesis Inducing Agents / Q000494:pharmacology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D056750:Cyclin A1 / Q000235:genetics*; D019927:Cyclin E / Q000235:genetics*; D051357:Cyclin-Dependent Kinase 2 / Q000378:metabolism; D053595:Embryonic Stem Cells / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D051547:Heme Oxygenase-1 / Q000235:genetics* / Q000378:metabolism; D061307:Human Umbilical Vein Endothelial Cells; D006801:Humans; D051379:Mice; D040901:Proteomics; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology*; D014746:Vimentin / Q000235:genetics*
chemical_list: D043925:Angiogenesis Inducing Agents; D056750:Cyclin A1; D019927:Cyclin E; D042461:Vascular Endothelial Growth Factor A; D014746:Vimentin; D051547:Heme Oxygenase-1; D051357:Cyclin-Dependent Kinase 2