title: Dual therapeutic utility of proteasome modulating agents for pharmaco-gene therapy of the cystic fibrosis airway.
abstract: Pharmacologic- and gene-based therapies have historically been developed as two independent therapeutic platforms for cystic fibrosis (CF) lung disease. Inhibition of the dysregulated epithelial Na channel (ENaC) is one pharmacologic approach to enhance airway clearance in CF. We investigated pharmacologic approaches to enhance CFTR gene delivery with recombinant adeno-associated virus (rAAV) and identified compounds that significantly improved viral transduction while simultaneously inhibiting ENaC activity through an unrelated mechanism. Treatment of human CF airway epithelia with proteasome modulating agents (LLnL and doxorubicin) at the time of rAAV2 or rAAV2/5 infection dramatically enhanced CFTR gene delivery and correction of CFTR-mediated short-circuit currents. Surprisingly, these agents also facilitated long-term (15-day) functional inhibition of ENaC currents independent of CFTR vector administration. Inhibition of ENaC activity was predominantly attributed to a doxorubicin-dependent decrease in gamma-ENaC subunit mRNA expression and an increase in gamma-ENaC promoter methylation. This is the first report to describe the identification of compounds with dual therapeutic action that are able to enhance the efficacy of CFTR gene therapy to the airway while simultaneously ameliorating primary aspects of CF disease pathophysiology. The identification of such compounds mark a new area for drug development, not only for CF, but also for other gene therapy disease targets.
authors.affiliation: Department of Anatomy and Cell Biology, University of Iowa College of Medicine, Iowa City, IA 52242, USA.
authors.forename: Liang N
authors.initials: LN
authors.lastname: Zhang
authors.forename: Phil
authors.initials: P
authors.lastname: Karp
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Gerard
authors.forename: Eric
authors.initials: E
authors.lastname: Pastor
authors.forename: Douglas
authors.initials: D
authors.lastname: Laux
authors.forename: Keith
authors.initials: K
authors.lastname: Munson
authors.forename: Ziying
authors.initials: Z
authors.lastname: Yan
authors.forename: Xiaoming
authors.initials: X
authors.lastname: Liu
authors.forename: Simon
authors.initials: S
authors.lastname: Godwin
authors.forename: Christie P
authors.initials: CP
authors.lastname: Thomas
authors.forename: Joseph
authors.initials: J
authors.lastname: Zabner
authors.forename: Huidong
authors.initials: H
authors.lastname: Shi
authors.forename: Charles W
authors.initials: CW
authors.lastname: Caldwell
authors.forename: Richard
authors.initials: R
authors.lastname: Peluso
authors.forename: Barrie
authors.initials: B
authors.lastname: Carter
authors.forename: John F
authors.initials: JF
authors.lastname: Engelhardt
mesh_terms: D000584:Amiloride / Q000494:pharmacology; D016764:Cell Polarity; D002478:Cells, Cultured; D018899:CpG Islands / Q000235:genetics; D003550:Cystic Fibrosis / Q000188:drug therapy / Q000235:genetics* / Q000378:metabolism / Q000628:therapy*; D019005:Cystic Fibrosis Transmembrane Conductance Regulator / Q000378:metabolism; D019175:DNA Methylation; D000229:Dependovirus / Q000235:genetics; D004317:Doxorubicin / Q000494:pharmacology*; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D053503:Epithelial Sodium Channels; D015316:Genetic Therapy / Q000379:methods*; D016679:Genome, Viral; D006801:Humans; D011401:Promoter Regions, Genetic / Q000235:genetics; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D061988:Proteasome Inhibitors; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D015222:Sodium Channels / Q000235:genetics / Q000378:metabolism; D013997:Time Factors
chemical_list: C505032:CFTR protein, human; D053503:Epithelial Sodium Channels; D061988:Proteasome Inhibitors; D012333:RNA, Messenger; D015222:Sodium Channels; D019005:Cystic Fibrosis Transmembrane Conductance Regulator; D000584:Amiloride; D004317:Doxorubicin; D012964:Sodium; D046988:Proteasome Endopeptidase Complex