Glucocorticoid Therapy Increases Cox-2 Gene Expression in Nasal Polyps in vivo (ERJ-00174-2008_R1)

¹ Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS); and Centro de Investigaciones Biomédicas en Red (CIBER) Enfermedades Respiratorias
² Servei d'Otorrinolaringologia
³ Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS); Centro de Investigaciones Biomédicas en Red (CIBER) Enfermedades Respiratorias; and Servei d'Otorrinolaringologia
⁴ Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS); Centro de Investigaciones Biomédicas en Red (CIBER) Enfermedades Respiratorias; and Servei de Pneumologia i Al.lèrgia Respiratoria, Hospital Clínic, Universitat de Barcelona, Spain

^* To whom correspondence should be addressed. E-mail: cpicado{at}ub.edu.

	Abstract

We aimed to evaluate the in vivo regulation of cyclooxygenase-2 in nasal polyps.

Sixty-five patients with nasal polyps, were randomly (3:1) treated (n=51, 33 with asthma) or not (n=14) with oral prednisone and intranasal budesonide for 2 weeks, plus intranasal budesonide for 10 additional weeks. Biopsies were obtained at baseline and after 2 and 12 weeks of treatment. All samples were analysed for cyclooxygenase-1 and cyclooxygenase-2 mRNA. Attempts were made to detect cyclooxygenase-2 protein.

At baseline, cyclooxygenase-1 and cyclooxygenase-2 expression did not differ between polyps from non-asthmatic and asthmatic patients. Cyclooxygenase-1 mRNA was unchanged by glucocorticoid treatment, while cyclooxygenase-2 mRNA increased in glucocorticoid-treated patients at week 2 (p<0.01) compared to baseline, and then decreased at week 12 (p<0.05 compared to week 2). Within subgroups, increased cyclooxygenase-2 mRNA was found at week 2 in polyps from non-asthmatic (p<0.05) and asthmatic patients (p<0.05) compared to baseline. At week 12, cyclooxygenase-2 expression remained high in non-asthmatics while it decreased in asthmatics (p<0.01 compared to week 2). Cyclooxygenase-2 protein was not detected under any circumstances.

Glucocorticoid therapy enhances cyclooxygenase-2 expression in vivo in nasal polyps, a finding that does not follow the generally accepted assumption that cyclooxygenase-2 expression is suppressed by glucocorticoids.