Expression of transcription factors NF-κB and AP-1 in nasal polyposis


Fabiana Cardoso Pereira Valera, Department of Ophthalmology, Otorhinolaryngology and Head and Neck Surgery, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Av. Bandeirantes, 3900, 14049-900 Ribeirão Preto, SP, Brazil.


Background The treatment and prognosis of nasal polyposis (NP) may be influenced by transcription factors, but their expression is poorly understood.

Objective To determine the expression of transcription factors [(nuclear factor-κB) NF-κB and (activator protein) AP-1], cytokines [IL-1β, TNF-α and (granulocytes and macrophage colony-stimulating factor) GM-CSF], growth factor (b-FGF), chemokine (eotaxin-2) and adhesion molecule (ICAM-1) in NP in comparison with nasal mucosa controls.

Methods Cross-sectional study. Twenty biopsies of nasal polyps were compared with eight middle turbinate biopsies. p65, c-Fos, IL-1β, TNF-α, ICAM-1, b-FGF, eotaxin-2 and GM-CSF were analysed through RQ-PCR, and p65 and c-Fos were also analysed through Western blotting.

Results NF-κB expression was increased in patients with NP when compared with control mucosa (P<0.05), whereas AP-1 expression did not differ significantly between groups. Expressions of IL-1β, eotaxin-2 and b-FGF were also increased in patients with NP compared with controls (P<0.05).

Conclusions The transcription factor NF-κB is more expressed in NP than in control mucosa. This is important in NP because NF-κB can induce the transcription of cytokines, chemokines and adhesion molecules, which play an important role in the inflammatory process. Moreover, transcription factors influence the response to corticosteroids, which are the basis of NP treatment. Transcription factor AP-1 does not seem to have a significant role in the pathological process.