Expression of leukotriene and its receptors in eosinophilic chronic rhinosinusitis with nasal polyps.

Background: Cysteinyl leukotriene (LT) has been proposed in the pathogenesis of chronic rhinosinusitis with nasal polyps (CRSwNP). This study sought to examine the expression of the LT receptor (LTR) in CRSwNP patients and evaluate the potential role of LTR antagonist (LTRA) in the management of eosinophilic CRSwNP (ECRS) patients.

Methods: Nasal polyps and uncinate process tissues were collected from 18 ECRS patients, 13 non-eosinophilic CRSwNP (non-ECRS) patients, and 16 control subjects. The messenger RNA (mRNA) and protein expression of LTR (cysteinyl leukotriene receptor 1 [CysLT1R] and cysteinyl leukotriene receptor 2 [CysLT2R]) was examined using quantitative reverse-transcription polymerase chain reaction (qRT-PCR), immunohistochemistry, and Western blot analysis. Moreover, the effects of LTRA and steroids on total nasal symptom scores (TNSS) of uncontrolled ECRS patients were evaluated.

Results: The mRNA and protein expression of CysLT1R and CysLT2R was significantly increased in polyp tissues compared with healthy controls (p < 0.05). Compared with the non-ECRS subset, the ECRS subset showed significantly increased expression of CysLT1R and CysLT2R, as well as leukotriene C4 (LTC4) and leukotriene D4 (LTC4) levels (p < 0.05). Moreover, combined LTRA and steroids significantly decreased TNSS more than steroids alone in uncontrolled ECRS patients (p < 0.01).

Conclusion: Our findings indicate that LTR was differentially expressed between ECRS and non-ECRS patients, and that LTRA may be used as an additional therapy for ECRS patients.