title: Endothelial-like malignant glioma cells in dynamic three dimensional culture identifies a role for VEGF and FGFR in a tumor-derived angiogenic response.
abstract: OBJECTIVE
  Recent studies have observed that cells from high-grade glial tumors are capable of assuming an endothelial phenotype and genotype, a process termed 'vasculogenic mimicry' (VM). Here we model and manipulate VM in dynamic 3-dimensional (3D) glioma cultures.
  
  
  METHODS
  The Rotary Cell Culture System (RCCS) was used to derive large macroscopic glioma aggregates, which were sectioned for immunohistochemistry and RNA extracted prior to angiogenic array-PCR.
  
  
  RESULTS
  A 3D cell culture induced microenvironment (containing only glial cells) is sufficient to promote expression of the endothelial markers CD105, CD31 and vWF in a proportion of glioma aggregates in vitro. Many pro-angiogenic genes were upregulated in glioma aggregates and in primary explants and glioma cells were capable of forming tubular-like 3D structures under endothelial-promoting conditions. Competitive inhibition of either vascular endothelial growth factor or fibroblast growth factor receptor was sufficient to impair VM and downregulate the tumor-derived angiogenic response, whilst impairing tumor cell derived tubule formation. Glioma xenografts using the same cells reveal tumor-derived vessel-like structures near necrotic areas, consistent with widespread tumor-derived endothelial expression in primary glioma tissue.
  
  
  CONCLUSIONS
  Our findings support studies indicating that tumor-derived endothelial cells arise in gliomas and describe a dynamic 3D culture as a bona fide model to interrogate the molecular basis of this phenomenon in vitro. Resistance to current anti-angiogenic therapies and the contribution of tumor derived endothelial cells to such resistance are amenable to study using the RCCS.
authors.affiliation: Children's Brain Tumor Research Centre, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: Stuart J
authors.initials: SJ
authors.lastname: Smith
authors.affiliation: Children's Brain Tumor Research Centre, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: Jennifer H
authors.initials: JH
authors.lastname: Ward
authors.affiliation: Children's Brain Tumor Research Centre, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: Christopher
authors.initials: C
authors.lastname: Tan
authors.affiliation: Children's Brain Tumor Research Centre, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: Richard G
authors.initials: RG
authors.lastname: Grundy
authors.affiliation: Children's Brain Tumor Research Centre, School of Medicine, University of Nottingham, Nottingham, UK.
authors.forename: Ruman
authors.initials: R
authors.lastname: Rahman
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D042783:Endothelial Cells / Q000378:metabolism / Q000473:pathology; D005910:Glioma / Q000098:blood supply* / Q000378:metabolism / Q000473:pathology; D064593:Heterografts; D006801:Humans; D051379:Mice; D008819:Mice, Nude; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000473:pathology; D017468:Receptors, Fibroblast Growth Factor / Q000378:metabolism*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism*
chemical_list: D017468:Receptors, Fibroblast Growth Factor; C467484:VEGFA protein, human; D042461:Vascular Endothelial Growth Factor A
keywords: angiogenesis; glioma; rotary cell culture system; tumor-derived endothelium; vasculogenic mimicry