title: Expression, localization, and significance of vascular permeability/vascular endothelial growth factor in nasal polyps.
abstract: BACKGROUND
  The exact etiologic mechanisms leading to the formation of nasal polyps have remained largely obscure. A key phenomenon of this specific type of chronic inflammatory disease in nasal respiratory mucosa is remarkable edema. Vascular permeability/vascular endothelial growth factor (VPF/VEGF) plays an important role in inducing angiogenesis and modulating capillary permeability.
  
  
  OBJECTIVE
  To study the expression and localization of VPF/ VEGF as a putative key factor in nasal polyp development.
  
  
  METHODS
  Specimens of nasal polyps (n = 12) were harvested during endonasal sinus surgery in patients with polypous chronic rhinosinusitis. Specimens of healthy nasal respiratory mucosa (n = 12) served as controls and were obtained from inferior turbinates of patients undergoing surgery for nasal obstruction without signs and symptoms of inflammatory disease. Frozen sections were immunohistochemically stained for VPF/VEGF and quantitatively analyzed, using computer-based image analysis.
  
  
  RESULTS
  The expression of VPF/VEGF in specimens of nasal polyps was significantly stronger than in specimens of healthy nasal mucosa of controls. VPF/VEGF in polypous tissue was mainly localized in vascular endothelial cells, in basal membranes and perivascular spaces, and in epithelial cells.
  
  
  CONCLUSIONS
  The markedly increased expression in nasal polyps as opposed to healthy nasal mucosa suggests that VPF/VEGF may play a significant role in both the formation of nasal polyps and in the induction of heavy tissue edema. This finding is discussed with respect to the differential expression of cyclooxygenase (COX) isoenzymes-1 and -2 (COX-1 and COX-2) in nasal polyps was significantly stronger than in specimens of healthy nasal mucosa of controls. VPF/VEGF in polypous tissue was mainly localized in vascular endothelial cells, in basal membranes and perivascular spaces, and in epithelial cells. Conclusion: The markedly increased expression in nasal polyps as opposed to healthy nasal mucosa suggests that VPF/VEGF may play a significant role in both the formation of nasal polyps and in the induction of heavy tissue edema. This finding is discussed with respect to the differential expression of cyclooxygenase (COX) isoenzymes-1 and -2 (COX-1 and COX-2) in nasal polyps.
authors.affiliation: Department of Otolaryngology, Head and Neck Surgery, University of Mainz, School of Medicine, Mainz, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Gosepath
authors.forename: Juergen
authors.initials: J
authors.lastname: Brieger
authors.forename: Hans Anton
authors.initials: HA
authors.lastname: Lehr
authors.forename: Wolf J
authors.initials: WJ
authors.lastname: Mann
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism; D002199:Capillary Permeability; D004730:Endothelium, Vascular / Q000378:metabolism / Q000473:pathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D009297:Nasal Mucosa / Q000098:blood supply / Q000378:metabolism; D009298:Nasal Polyps / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000473:pathology; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis*
chemical_list: D015415:Biomarkers; D042461:Vascular Endothelial Growth Factor A