title: Correctors and Potentiators Rescue Function of the Truncated W1282X-Cystic Fibrosis Transmembrane Regulator (CFTR) Translation Product.
abstract: W1282X is the fifth most common cystic fibrosis transmembrane regulator (CFTR) mutation that causes cystic fibrosis. Here, we investigated the utility of a small molecule corrector/potentiator strategy, as used for ΔF508-CFTR, to produce functional rescue of the truncated translation product of the W1282X mutation, CFTR1281, without the need for read-through. In transfected cell systems, certain potentiators and correctors, including VX-809 and VX-770, increased CFTR1281activity. To identify novel correctors and potentiators with potentially greater efficacy on CFTR1281, functional screens were done of ∼30,000 synthetic small molecules and drugs/nutraceuticals in CFTR1281-transfected cells. Corrector scaffolds of 1-arylpyrazole-4-arylsulfonyl-piperazine and spiro-piperidine-quinazolinone classes were identified with up to ∼5-fold greater efficacy than VX-809, some of which were selective for CFTR1281, whereas others also corrected ΔF508-CFTR. Several novel potentiator scaffolds were identified with efficacy comparable with VX-770; remarkably, a phenylsulfonamide-pyrrolopyridine acted synergistically with VX-770 to increase CFTR1281function ∼8-fold over that of VX-770 alone, normalizing CFTR1281channel activity to that of wild type CFTR. Corrector and potentiator combinations were tested in primary cultures and conditionally reprogrammed cells generated from nasal brushings from one W1282X homozygous subject. Although robust chloride conductance was seen with correctors and potentiators in homozygous ΔF508 cells, increased chloride conductance was not found in W1282X cells despite the presence of adequate transcript levels. Notwithstanding the negative data in W1282X cells from one human subject, we speculate that corrector and potentiator combinations may have therapeutic efficacy in cystic fibrosis caused by the W1282X mutation, although additional studies are needed on human cells from W1282X subjects.
authors.affiliation: From the Departments of Medicine, peter.haggie@ucsf.edu.|Physiology.
authors.forename: Peter M
authors.initials: PM
authors.lastname: Haggie
authors.affiliation: From the Departments of Medicine.|Physiology.
authors.forename: Puay-Wah
authors.initials: PW
authors.lastname: Phuan
authors.affiliation: From the Departments of Medicine.|Physiology.
authors.forename: Joseph-Anthony
authors.initials: JA
authors.lastname: Tan
authors.affiliation: the Department of Physiology, McGill University, Montreal, Quebec H3G 1Y6, Canada.
authors.forename: Haijin
authors.initials: H
authors.lastname: Xu
authors.affiliation: the Department of Physiology, McGill University, Montreal, Quebec H3G 1Y6, Canada.
authors.forename: Radu G
authors.initials: RG
authors.lastname: Avramescu
authors.affiliation: the Department of Physiology, McGill University, Montreal, Quebec H3G 1Y6, Canada.
authors.forename: Doranda
authors.initials: D
authors.lastname: Perdomo
authors.affiliation: Pathology, and.
authors.forename: Lorna
authors.initials: L
authors.lastname: Zlock
authors.affiliation: Pediatrics, University of California, San Francisco, California 94143-0521 and.
authors.forename: Dennis W
authors.initials: DW
authors.lastname: Nielson
authors.affiliation: Pathology, and.
authors.forename: Walter E
authors.initials: WE
authors.lastname: Finkbeiner
authors.affiliation: the Department of Physiology, McGill University, Montreal, Quebec H3G 1Y6, Canada gergely.lukacs@mcgill.ca.
authors.forename: Gergely L
authors.initials: GL
authors.lastname: Lukacs
authors.affiliation: From the Departments of Medicine, alan.verkman@ucsf.edu.|Physiology.
authors.forename: Alan S
authors.initials: AS
authors.lastname: Verkman
mesh_terms: D019943:Amino Acid Substitution; D000627:Aminophenols / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D020125:Mutation, Missense; D010879:Piperazines / Q000494:pharmacology*; D015363:Quinolones / Q000494:pharmacology*; D051381:Rats; D011916:Rats, Inbred F344
chemical_list: D000627:Aminophenols; C505032:CFTR protein, human; D010879:Piperazines; D015363:Quinolones; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; C545203:ivacaftor
keywords: cystic fibrosis; cystic fibrosis transmembrane conductance regulator (CFTR); drug discovery; drug screening; small molecule