Differential Expression of the Aryl Hydrocarbon Receptor and Transforming Growth Factor Beta 1 in Chronic Rhinosinusitis with Nasal Polyps with Allergic Rhinitis

<b><i>Objective:</i></b> This study aimed to determine the aryl hydrocarbon receptor (AhR) and transforming growth factor beta 1 (TGF-β1) expression levels in chronic rhinosinusitis (CRS) and their possible correlation with allergic state and tissue remodeling. <b><i>Methods:</i></b> Patients were enrolled and divided into the following groups: CRS without nasal polyps (NP) without allergic rhinitis (AR) (CRSsNPsAR; <i>n</i> = 20), CRS with NP with AR (CRSwNPwAR; <i>n</i> = 20), CRS with NP without AR (CRSwNPsAR; <i>n</i> = 20), and controls (<i>n</i> = 15). Tissue samples were analyzed by Masson trichrome staining for collagen, while the location and expression of AhR and TGF-β1 were analyzed by immunohistochemistry, quantitative reverse transcription polymerase chain reaction (qRT-PCR), and Western blotting. <b><i>Results:</i></b> The collagen amounts as well as AhR and TGF-β1 mRNA and protein expression levels were significantly increased in the CRSsNPsAR group compared with the CRSwNP (CRSwNPsAR and CRSwNPwAR) samples (<i>p</i> < 0.01). However, higher collagen amounts (<i>p</i> < 0.05) and higher TGF-β1 (<i>p</i> < 0.05) but lower AhR expression levels (<i>p</i> < 0.05) were detected in the CRSwNPwAR versus the CRSwNPsAR patients. Both AhR and TGF-β1 expression were positively correlated with the collagen level in CRS samples (<i>p</i> < 0.01). <b><i>Conclusions:</i></b> Elevated AhR expression may be involved in the progression of tissue remodeling in CRSsNPsAR similar to TGF-β1 expression. Conversely, lower AhR expression may be involved in allergic reactions in CRSwNPwAR.