The aim of the current study was therefore to investigate the effect of EGF on mucin MUC5AC expression and define the involvement of PI3K and TMEM16A in mediating the EGF-induced MUC5AC expression in primary nasal epithelial cell cultures derived from polyp tissue of CRSwNP patients. This evidence concerns the gene MUC5AC and chronic rhinosinusitis with nasal polyps.