title: Proprotein convertase inhibition promotes ciliated cell differentiation - a potential mechanism for the inhibition of Notch1 signalling by decanoyl-RVKR-chloromethylketone.
abstract: Chronic repetitive rounds of injury and repair in the airway lead to airway remodelling, including ciliated cell loss and mucous cell hyperplasia. Airway remodelling is mediated by many growth and differentiation factors including Notch1, which are proteolytically processed by proprotein convertases (PCs). The present study evaluated a novel approach for controlling basal cell-type determination based on the inhibition of PCs. It was found that decanoyl-RVKR-chloromethylketone (CMK), a PC inhibitor, promotes ciliated cell differentiation and has no effect on the ciliary beat frequency in air-liquid interface (ALI) cultures of human nasal epithelial cells (HNECs). Comparative microarray analysis revealed that CMK considerably increases ciliogenesis-related gene expression. Use of cell-permeable and cell-impermeable PC inhibitors suggests that intracellular PCs regulate basal cell-type determination in ALI culture. Furthermore, CMK effect on ciliated cell differentiation was reversed by a Notch inhibitor N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT). CMK inhibited the processing of Notch1, a key regulator of basal cell differentiation toward secretory cell lineages in the airway epithelium, and down-regulated the expression of Notch1 target genes together with furin, a PC. Specific lentiviral shRNA-mediated knockdown of furin resulted in reduced Notch1 processing and increased numbers of ciliated cells in HNECs. Moreover, CMK inhibited Notch1 processing and promoted regeneration and ciliogenesis of the mouse nasal respiratory epithelium after ZnSO4injury. These observations suggest that PC inhibition promotes airway ciliated cell differentiation, possibly through suppression of furin-mediated Notch1 processing. © 2016 The Authors Journal of Tissue Engineering and Regenerative Medicine Published by John Wiley & Sons Ltd.
authors.affiliation: Research Centre for Human Natural Defence System, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Sang-Nam
authors.initials: SN
authors.lastname: Lee
authors.affiliation: Research Centre for Human Natural Defence System, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: In-Suk
authors.initials: IS
authors.lastname: Choi
authors.affiliation: Department of Otorhinolaryngology, School of Medicine, Ajou University, Seoul, Korea.
authors.forename: Hyun Jun
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Clinical Research Division, Korea Institute of Oriental Medicine, Seoul, Korea.
authors.forename: Eun Jin
authors.initials: EJ
authors.lastname: Yang
authors.affiliation: Department of Otorhinolaryngology-Head and Neck Surgery, Chung-Ang University College of Medicine, Seoul, Korea.
authors.forename: Hyun Jin
authors.initials: HJ
authors.lastname: Min
authors.affiliation: Research Centre for Human Natural Defence System, Yonsei University College of Medicine, Seoul, Korea.|Department of Otorhinolaryngology, Yonsei University College of Medicine, Seoul, Korea.|The Airway Mucus Institute, Yonsei University College of Medicine, Seoul, Korea.
authors.forename: Joo-Heon
authors.initials: JH
authors.lastname: Yoon
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology*; D002454:Cell Differentiation / Q000187:drug effects*; D002923:Cilia / Q000378:metabolism; D004847:Epithelial Cells / Q000166:cytology / Q000378:metabolism*; D045683:Furin / Q000378:metabolism; D006801:Humans; D009297:Nasal Mucosa / Q000166:cytology / Q000378:metabolism*; D043484:Proprotein Convertases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology*; D051881:Receptor, Notch1 / Q000378:metabolism*
chemical_list: D000590:Amino Acid Chloromethyl Ketones; C497761:NOTCH1 protein, human; D011500:Protein Synthesis Inhibitors; D051881:Receptor, Notch1; D043484:Proprotein Convertases; C468731:FURIN protein, human; D045683:Furin
keywords: airway remodelling; basal progenitor cells; ciliated cell differentiation; cultured human nasal epithelial cells; notch1; proprotein convertases