Objective To explore the mechanism of hypoxia on the expressions of airway remodelingassociated factors matrix metalloproteinase-9(MMP-9)and transforming growth factorβ_1(TGF-β_1)in human airway epithelial cells(16 HBE)under hypoxia.Methods We cultured 16 HBE cells under normoxia or hypoxia(20 mL/L O2)for 6,12 and 24 hours.MMP-9 and TGF-β_1 with higher expression were pretreated with epidermal growth factor receptor(EGFR)inhibitor AG1478 and hypoxia-inducible factor-1α(HIF-1α)inhibitor Lificiguat(YC-1).Cell...