title: Relationship between matrix metalloproteinases MMP-2, MMP-9, tissue inhibitor of matrix metalloproteinases-1 and IL-5, IL-8 in nasal polyps.
abstract: BACKGROUND
  Nasal polyps (NP), a subgroup of chronic rhinosinusitis, are characterized by interleukin 5 (IL-5) mediated infiltration of eosinophils in sinus mucosa, leading to pseudostratified ciliated columnar epithelium, thickening of the epithelial basement membrane and tissue edema. Matrix metalloproteinases (MMP) constitute a large group of Zn2+ dependent endopeptidases with the ability to degrade extracellular matrix and are possibly responsible for the development of tissue edema in chronic sinusitis.
  
  
  OBJECTIVE
  The aim of this study was to determine the expression of MMP-2, MMP-9 and tissue inhibitor of matrix metalloproteinase-1 (TIMP-1) mRNA and to locate the distribution of MMP-2, MMP-9 and TIMP-1 by immunohistochemistry in ethmoid sinus mucosa in NP. Furthermore the correlation between IL-5 or IL-8 and MMP-2, MMP-9 or TIMP-1 is examined.
  
  
  METHODS
  Nasal polyps of 33 patients and 18 specimens of inferior turbinate mucosa were examined by real time RT-PCR for MMP-2, MMP-9, TIMP-1, IL-5 and IL-8 mRNA expression. Immunohistochemical labeling for MMP-2, MMP-9 and TIMP-1 was performed.
  
  
  RESULTS
  Differences between both locations were detectable for MMP-9 (P < 0.001) and IL-5 (P=0.003) but not for MMP-2 (P=0.278), TIMP-1 (P=0.515) and IL-8 (P=0.386). Correlation was detected only between TIMP-1 and IL-5 (r=0.422, P =0.014). Cytoplasmic staining of MMP-2 was present in the apical part of the ciliated cells, submucosal glands and in smooth muscle cells. Matrix metalloproteinase-9 was expressed in surface epithelium, in seromucous glands and in polymorphonuclear cells.
  
  
  CONCLUSIONS
  Expression of MMP-9 and IL-5 mRNA are associated with NP. The correlation between IL-5 and TIMP-1 indicates the role of TIMP-1 in maintaining the homeostasis in NP.
authors.affiliation: Department of Otorhinolaryngology, Plastic Head and Neck Surgery, University Hospital RWTH Aachen, Germany.
authors.forename: Y-S
authors.initials: YS
authors.lastname: Chen
authors.forename: T
authors.initials: T
authors.lastname: Langhammer
authors.forename: M
authors.initials: M
authors.lastname: Westhofen
authors.forename: J
authors.initials: J
authors.lastname: Lorenzen
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D015848:Interleukin-5 / Q000378:metabolism*; D016209:Interleukin-8 / Q000378:metabolism*; D008297:Male; D020778:Matrix Metalloproteinase 2 / Q000378:metabolism*; D020780:Matrix Metalloproteinase 9 / Q000378:metabolism*; D008875:Middle Aged; D009298:Nasal Polyps / Q000201:enzymology / Q000378:metabolism* / Q000473:pathology; D014018:Tissue Distribution; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism*
chemical_list: D015848:Interleukin-5; D016209:Interleukin-8; D019715:Tissue Inhibitor of Metalloproteinase-1; D020778:Matrix Metalloproteinase 2; D020780:Matrix Metalloproteinase 9