title: Hypoxia-inducible factor 1 upregulation of both VEGF and ANGPTL4 is required to promote the angiogenic phenotype in uveal melanoma.
abstract: OBJECTIVE
  Expression of the hypoxia-inducible factor (HIF)-1-regulated gene product, vascular endothelial growth factor (VEGF), correlates with tumor vascularity in patients with uveal melanoma (UM). While the relationship between HIF-1 and VEGF in cancer is well-studied, their relative contribution to the angiogenic phenotype in UM has not previously been interrogated. Here we evaluate the contribution of HIF-1, VEGF, and a second HIF-1-regulated gene product, angiopoietin-like 4 (ANGPTL4), to angiogenesis in UM.
  
  
  METHODS
  UM cells were examined for expression of HIF-1α, VEGF, and ANGPTL4. Their contribution to the angiogenic potential of UM cells was assessed using the endothelial cell tubule formation and directed in vivo angiogenesis assays. These results were corroborated in tissue from UM animal models and in tissue from patients with UM.
  
  
  RESULTS
  Inhibition of VEGF partially reduced tubule formation promoted by conditioned medium from UM cells. Inhibition of ANGPTL4, which was highly expressed in hypoxic UM cells, a UM orthotopic transplant model, a UM tumor array, and vitreous samples from UM patients, inhibited the angiogenic potential of UM cells in vitro and in vivo; this effect was additive to VEGF inhibition.
  
  
  CONCLUSIONS
  Targeting both ANGPTL4 and VEGF may be required for the effective inhibition of angiogenesis in UM.
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.|The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Hu
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: Savalan
authors.initials: S
authors.lastname: Babapoor-Farrokhran
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: Murilo
authors.initials: M
authors.lastname: Rodrigues
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: Monika
authors.initials: M
authors.lastname: Deshpande
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: Brooks
authors.initials: B
authors.lastname: Puchner
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: Fabiana
authors.initials: F
authors.lastname: Kashiwabuchi
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: Syed Junaid
authors.initials: SJ
authors.lastname: Hassan
authors.affiliation: Department of Pathology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
authors.forename: Laura
authors.initials: L
authors.lastname: Asnaghi
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: James T
authors.initials: JT
authors.lastname: Handa
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: Shannath
authors.initials: S
authors.lastname: Merbs
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.|Department of Pathology, Johns Hopkins University, School of Medicine, Baltimore, MD, USA.
authors.forename: Charles G
authors.initials: CG
authors.lastname: Eberhart
authors.affiliation: Departments of Pediatrics, Medicine, Oncology, Radiation Oncology, Biological Chemistry, and Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Gregg L
authors.initials: GL
authors.lastname: Semenza
authors.affiliation: Department of Oncology and Diagnostic Sciences, Greenebaum Cancer Center, University of Maryland, Baltimore, MD, USA.
authors.forename: Silvia
authors.initials: S
authors.lastname: Montaner
authors.affiliation: Wilmer Eye Institute, Johns Hopkins School of Medicine, Baltimore, MD, USA.
authors.forename: Akrit
authors.initials: A
authors.lastname: Sodhi
mesh_terms: D000075803:Angiopoietin-Like Protein 4; D042682:Angiopoietins / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D016022:Case-Control Studies; D015687:Cell Hypoxia; D002465:Cell Movement; D049109:Cell Proliferation; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000378:metabolism / Q000473:pathology; D005260:Female; D005455:Fluorescent Antibody Technique; D005500:Follow-Up Studies; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D008545:Melanoma / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D009367:Neoplasm Staging; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000473:pathology*; D010641:Phenotype; D011379:Prognosis; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014604:Uveal Neoplasms / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism*; D023041:Xenograft Model Antitumor Assays; D000098943:Uveal Melanoma
chemical_list: C474772:ANGPTL4 protein, human; D000075803:Angiopoietin-Like Protein 4; D042682:Angiopoietins; C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D012333:RNA, Messenger; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A
keywords: angiogenesis; angiopoietin-like 4 (ANGPTL4); choroidal melanoma; hypoxia inducible factor-1α; vascular endothelial growth factor (VEGF)