Cyclooxygenase 1 and cyclooxygenase 2 expression is abnormally regulated in human nasal polyps.
BACKGROUND
There is evidence that impairment of prostanoid metabolism might be involved in the pathogenesis of nasal polyps (NPs). Prostanoids are synthesized by 2 cyclooxygenase (Cox) enzymes, one constitutive (Cox-1) and another inducible (Cox-2).


OBJECTIVE
The aim of these studies was to investigate Cox-1 and Cox-2 regulation in NPs of aspirin-tolerant human patients compared with that seen in nasal mucosa (NM).


METHODS
Cultured explants from human NPs and healthy mucosa from patients undergoing polypectomy and corrective nasal surgery, respectively, were examined for Cox-1 and Cox-2 expression by means of semiquantitative competitive PCR and Western blotting.


RESULTS
Cox-1 mRNA was spontaneously upregulated in cultured NM but not in NPs. A spontaneous but delayed upregulation of Cox-2 mRNA was found in NPs (24 hours) compared with that seen in NM (6 hours). After cytokine stimulation (IFN-gamma, IL-1beta, and TNF-alpha), the induction of Cox-2 mRNA and protein was also faster in NM (1 hour) than in NPs (4 hours).


CONCLUSIONS
These data showing an abnormal regulation of Cox-1 and Cox-2 in NPs from aspirin-tolerant patients reinforce the concept that prostanoid metabolism might be important in the pathogenesis of inflammatory nasal diseases and suggest a potential role for this alteration in the formation of NPs.
Mullol
Joaquim
J
Institut d'Investigacions Biomèdiques August Pi I Sunyer, Institut Clínic de Pneumologia I Cirurgia Toràcica, Hospital Clínic, Barcelona, Spain.
Fernàndez-Morata
Joan C
JC
Roca-Ferrer
Jordi
J
Pujols
Laura
L
Xaubet
Antoni
A
Benitez
Pedro
P
Picado
Cesar
C
D000293:Adolescent; D000328:Adult; D000368:Aged; D046508:Culture Techniques; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism*; D008565:Membrane Proteins; D008875:Middle Aged; D009297:Nasal Mucosa / Q000201:enzymology; D009298:Nasal Polyps / Q000201:enzymology* / Q000378:metabolism; D011451:Prostaglandin-Endoperoxide Synthases / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D012016:Reference Values; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D007375:Interleukin-1; D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496511:PTGS1 protein, human; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases