title: COX-2 is widely expressed in metaplastic epithelium in pulmonary fibrous disorders.
abstract: Idiopathic usual interstitial pneumonia/idiopathic pulmonary fibrosis (UIP/IPF) and asbestosis represent progressive and often fatal pulmonary fibrous disorders, whereas cryptogenic organizing pneumonia (COP), desquamative interstitial pneumonia (DIP), and respiratory bronchiolitis-interstitial lung disease (RB-ILD) usually are reversible or nonprogressive conditions. Prostaglandin E2 (PGE2) inhibits fibroblast proliferation and myofibroblast transition, its production depending on cyclooxygenase-2 (COX-2). In patients with UIP/IPF, levels of PGE2 and COX-2 are reduced in fibroblasts, and levels of PGE2 in bronchioalveolar lavage fluid may be lowered. We analyzed the immunohistochemical expression of COX-2 in UIP/IPF, asbestosis, COP, DIP, and RB-ILD. Our results show that the metaplastic epithelium in UIP/IPF, asbestosis, and COP is widely COX-2+, whereas COX-2 positivity is scant in DIP and RB-ILD. The mesenchymal cells remained negative. Our results suggest that irrespective of the underlying disease, lung injury that causes extensive fibrosis induces wide expression of COX-2 in the regenerating metaplastic epithelium.
authors.affiliation: Department of Pathology, Oulu, University, Oulu, Finland.
authors.forename: Elisa
authors.initials: E
authors.lastname: Lappi-Blanco
authors.forename: Riitta
authors.initials: R
authors.lastname: Kaarteenaho-Wiik
authors.forename: Paula K
authors.initials: PK
authors.lastname: Maasilta
authors.forename: Sisko
authors.initials: S
authors.lastname: Anttila
authors.forename: Paavo
authors.initials: P
authors.lastname: Pääkkö
authors.forename: Henrik J
authors.initials: HJ
authors.lastname: Wolff
mesh_terms: D001195:Asbestosis / Q000201:enzymology / Q000473:pathology; D001988:Bronchiolitis / Q000201:enzymology / Q000473:pathology; D018549:Cryptogenic Organizing Pneumonia / Q000201:enzymology / Q000473:pathology; D051546:Cyclooxygenase 2 / Q000378:metabolism*; D004848:Epithelium / Q000201:enzymology / Q000473:pathology; D006801:Humans; D007150:Immunohistochemistry; D017563:Lung Diseases, Interstitial / Q000201:enzymology / Q000473:pathology; D008565:Membrane Proteins / Q000378:metabolism*; D008679:Metaplasia; D011658:Pulmonary Fibrosis / Q000201:enzymology / Q000473:pathology*
chemical_list: D008565:Membrane Proteins; D051546:Cyclooxygenase 2; C496540:PTGS2 protein, human