Objectives: Demonstrate the induction of cyclooxygenase-2 (COX-2) in laryngeal papilloma Discuss the possible causal role of COX-2 in papilloma formation. Consider the potential for treatment of papilloma using selective COX-2 inhibitors.
Study design: Molecular biological analysis of COX-1 and COX-2 in laryngeal papilloma.
Methods: Tissue samples from five patients with recurrent respiratory papillomatosis (RRP) were analyzed by in situ hybridization, immunohistochemical staining, and reverse transcription polymerase chain reaction (RT-PCR) techniques.
Results: In situ hybridization to COX-2 mRNA showed strong autoradiographic signal surrounding fibrovascular cores. COX-1 autoradiographic signal was low intensity or nondetectable. Normal buccal mucosa biopsies showed low-density or nondetectable autoradiographic signal for both COX-1 and COX-2 mRNAs. In situ hybridization results were corroborated by RT-PCR studies. Levels of COX-2 mRNA were 13-fold more than those in normal mucosa. Immunohistochemical staining for COX-1 and COX-2 showed a similar pattern to that seen with in situ hybridization in both normal and papilloma tissues.
Conclusions: There is an elevation of COX-2 expression in papilloma tissues. This may represent a causal role of COX-2 in the formation and proliferation of laryngeal papilloma. There may also be a role for selective COX-2 inhibition for the treatment of