Aberrant expression of miR-663 and transforming growth factor-β1 in nasal polyposis in children

The aim of the present study was to investigate the expression of microRNA (miR)-663 and its regulatory effects on the pathogenesis of nasal polyposis in children. Nasal polyp tissue, as well as serum and peripheral blood eosinophils were collected from 35 children diagnosed with nasal polypectomy between August 2013 and August 2015. As a control, the inferior nasal concha, serum and peripheral blood eosinophils were collected from 46 patients with nasal septal deviation complicated by inferior turbinate hypertrophy or patients with simple inferior turbinate hypertrophy who had undergone surgical removal of the inferior nasal concha. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to measure the expression of miR-663 and transforming growth factor-β1 (TGF-β1) in the nasal polyp tissue, serum and peripheral blood eosinophils of patients with nasal polyposis and controls. Western blotting was used to measure the expression of TGF-β1 protein in nasal tissue and eosinophils and an enzyme-linked immunosorbent assay was used to measure serum level of TGF-β1 protein. A dual luciferase reporter assay was used to determine whether TGF-β1 was a target gene of miR-663. Compared with the control group, levels of TGF-β1 mRNA and protein were significantly increased in all three types of specimens from pediatric patients with nasal polyposis (P<0.05). miR-663 expression was significantly decreased in nasal polyp tissue and peripheral blood eosinophils (P<0.05). The dual luciferase reporter assay confirmed that TGF-β1 was a target gene of miR-663. The current study suggests that the upregulation of TGF-β1 may be associated with the downregulation of miR-663 in nasal polyposis in children. miR-663 may have regulatory effects on the pathogenesis of nasal polyposis by regulating TGF-β1 and may be developed as a genetic marker of nasal polyposis in children.