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Kamada Y, Ohnishi Y, Nakashima C, Fujii A, Terakawa M, Hamano I, Nakayamada U, Katoh S, Hirata N, Tateishi H, Fukuda R, Takahashi H, Lukacs GL, Okiyoneda T. HERC3 facilitates ERAD of select membrane proteins by recognizing membrane-spanning domains. J Cell Biol 2024; 223:e202308003. [PMID: 38722278 PMCID: PMC11082371 DOI: 10.1083/jcb.202308003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 02/22/2024] [Accepted: 03/18/2024] [Indexed: 05/12/2024] Open
Abstract
Aberrant proteins located in the endoplasmic reticulum (ER) undergo rapid ubiquitination by multiple ubiquitin (Ub) E3 ligases and are retrotranslocated to the cytosol as part of the ER-associated degradation (ERAD). Despite several ERAD branches involving different Ub E3 ligases, the molecular machinery responsible for these ERAD branches in mammalian cells remains not fully understood. Through a series of multiplex knockdown/knockout experiments with real-time kinetic measurements, we demonstrate that HERC3 operates independently of the ER-embedded ubiquitin ligases RNF5 and RNF185 (RNF5/185) to mediate the retrotranslocation and ERAD of misfolded CFTR. While RNF5/185 participates in the ERAD process of both misfolded ABCB1 and CFTR, HERC3 uniquely promotes CFTR ERAD. In vitro assay revealed that HERC3 directly interacts with the exposed membrane-spanning domains (MSDs) of CFTR but not with the MSDs embedded in liposomes. Therefore, HERC3 could play a role in the quality control of MSDs in the cytoplasm and might be crucial for the ERAD pathway of select membrane proteins.
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Affiliation(s)
- Yuka Kamada
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Yuko Ohnishi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Chikako Nakashima
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Aika Fujii
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Mana Terakawa
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Ikuto Hamano
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Uta Nakayamada
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Saori Katoh
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Noriaki Hirata
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Hazuki Tateishi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Ryosuke Fukuda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
| | - Hirotaka Takahashi
- Division of Cell-Free Sciences, Proteo-Science Center (PROS), Ehime University, Matsuyama, Japan
| | - Gergely L. Lukacs
- Department of Physiology, McGill University, Montréal, Canada
- Department of Biochemistry, McGill University, Montréal, Canada
| | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Sanda, Japan
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Okiyoneda T, Borgo C, Bosello Travain V, Pedemonte N, Salvi M. Targeting ubiquitination machinery in cystic fibrosis: Where do we stand? Cell Mol Life Sci 2024; 81:271. [PMID: 38888668 DOI: 10.1007/s00018-024-05295-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 05/16/2024] [Accepted: 05/25/2024] [Indexed: 06/20/2024]
Abstract
Cystic Fibrosis (CF) is a genetic disease caused by mutations in CFTR gene expressing the anion selective channel CFTR located at the plasma membrane of different epithelial cells. The most commonly investigated variant causing CF is F508del. This mutation leads to structural defects in the CFTR protein, which are recognized by the endoplasmic reticulum (ER) quality control system. As a result, the protein is retained in the ER and degraded via the ubiquitin-proteasome pathway. Although blocking ubiquitination to stabilize the CFTR protein has long been considered a potential pharmacological approach in CF, progress in this area has been relatively slow. Currently, no compounds targeting this pathway have entered clinical trials for CF. On the other hand, the emergence of Orkambi initially, and notably the subsequent introduction of Trikafta/Kaftrio, have demonstrated the effectiveness of molecular chaperone-based therapies for patients carrying the F508del variant and even showed efficacy against other variants. These treatments directly target the CFTR variant protein without interfering with cell signaling pathways. This review discusses the limits and potential future of targeting protein ubiquitination in CF.
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Affiliation(s)
- Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo, 669-1330, Japan.
| | - Christian Borgo
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy
- Department of Medicine, University of Padova, 35128, Padova, Italy
| | | | - Nicoletta Pedemonte
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genoa, Italy
| | - Mauro Salvi
- Department of Biomedical Sciences, University of Padova, 35131, Padova, Italy.
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Taniguchi S, Berenger F, Doi Y, Mimura A, Yamanishi Y, Okiyoneda T. Ligand-based virtual-screening identified a novel CFTR ligand which improves the defective cell surface expression of misfolded ABC transporters. Front Pharmacol 2024; 15:1370676. [PMID: 38666024 PMCID: PMC11043560 DOI: 10.3389/fphar.2024.1370676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Accepted: 04/01/2024] [Indexed: 04/28/2024] Open
Abstract
Cystic fibrosis (CF) is a monogenetic disease caused by the mutation of CFTR, a cAMP-regulated Cl- channel expressing at the apical plasma membrane (PM) of epithelia. ∆F508-CFTR, the most common mutant in CF, fails to reach the PM due to its misfolding and premature degradation at the endoplasmic reticulum (ER). Recently, CFTR modulators have been developed to correct CFTR abnormalities, with some being used as therapeutic agents for CF treatment. One notable example is Trikafta, a triple combination of CFTR modulators (TEZ/ELX/IVA), which significantly enhances the functionality of ΔF508-CFTR on the PM. However, there's room for improvement in its therapeutic effectiveness since TEZ/ELX/IVA doesn't fully stabilize ΔF508-CFTR on the PM. To discover new CFTR modulators, we conducted a virtual screening of approximately 4.3 million compounds based on the chemical structures of existing CFTR modulators. This effort led us to identify a novel CFTR ligand named FR3. Unlike clinically available CFTR modulators, FR3 appears to operate through a distinct mechanism of action. FR3 enhances the functional expression of ΔF508-CFTR on the apical PM in airway epithelial cell lines by stabilizing NBD1. Notably, FR3 counteracted the degradation of mature ΔF508-CFTR, which still occurs despite the presence of TEZ/ELX/IVA. Furthermore, FR3 corrected the defective PM expression of a misfolded ABCB1 mutant. Therefore, FR3 may be a potential lead compound for addressing diseases resulting from the misfolding of ABC transporters.
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Affiliation(s)
- Shogo Taniguchi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Nishinomiya, Japan
| | - Francois Berenger
- Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa, Japan
| | - Yukako Doi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Nishinomiya, Japan
| | - Ayana Mimura
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Nishinomiya, Japan
| | - Yoshihiro Yamanishi
- Department of Complex Systems Science, Graduate School of Informatics, Nagoya University, Graduate School of Informatics, Nagoya University, Nagoya, Japan
| | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Nishinomiya, Japan
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Ferreira FC, Amaral MD, Bacalhau M, Lopes-Pacheco M. PTI-801 (posenacaftor) shares a common mechanism with VX-445 (elexacaftor) to rescue p.Phe508del-CFTR. Eur J Pharmacol 2024; 967:176390. [PMID: 38336013 DOI: 10.1016/j.ejphar.2024.176390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 01/05/2024] [Accepted: 02/01/2024] [Indexed: 02/12/2024]
Abstract
The deletion of a phenylalanine at position 508 (p.Phe508del) in the CFTR anion channel is the most prevalent variant in people with Cystic Fibrosis (CF). This variant impairs folding and stability of the CF transmembrane conductance regulator (CFTR) protein, resulting in its defective trafficking and premature degradation. Over the last years, therapeutic accomplishments have been attained in developing small molecules that partially correct p.Phe508del-CFTR defects; however, the mechanism of action (MoA) of these compounds has only started to be uncovered. In this study, we employed biochemical, fluorescence microscopy, and functional assays to examine the efficacy and properties of PTI-801, a newly developed p.Phe508del-CFTR corrector. To exploit its MoA, we assessed PTI-801 effects in combination with low temperature, genetic revertants of p.Phe508del-CFTR (the in cis p.Val510Asp, p.Gly550Glu, p.Arg1070Trp, and 4RK) and other correctors. Our results demonstrated that PTI-801 rescues p.Phe508del-CFTR processing, PM trafficking, and channel function (upon agonist stimulation) with greater correction effects in combination with ABBV-2222, FDL-169, VX-661, or VX-809, but not with VX-445. Although PTI-801 exhibited no potentiator activity on low temperature- and corrector-rescued p.Phe508del-CFTR, this compound displayed similar behavior to that of VX-445 on genetic revertants. Such evidence associated with the lack of additivity when PTI-801 and VX-445 were combined indicates that they share a common binding site to correct p.Phe508del-CFTR defects. Despite the high efficacy of PTI-801 in combination with ABBV-2222, FDL-169, VX-661, or VX-809, these dual corrector combinations only partially restored p.Phe508del-CFTR conformational stability, as shown by the lower half-life of the mutant protein compared to that of WT-CFTR. In summary, PTI-801 likely shares a common MoA with VX-445 in rescuing p.Phe508del-CFTR, thus being a feasible alternative for the development of novel corrector combinations with greater capacity to rescue mutant CFTR folding and stability.
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Affiliation(s)
- Filipa C Ferreira
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016, Lisbon, Portugal
| | - Margarida D Amaral
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016, Lisbon, Portugal
| | - Mafalda Bacalhau
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016, Lisbon, Portugal
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016, Lisbon, Portugal.
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Borgo C, D’Amore C, Capurro V, Tomati V, Pedemonte N, Bosello Travain V, Salvi M. SUMOylation Inhibition Enhances Protein Transcription under CMV Promoter: A Lesson from a Study with the F508del-CFTR Mutant. Int J Mol Sci 2024; 25:2302. [PMID: 38396982 PMCID: PMC10889535 DOI: 10.3390/ijms25042302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Revised: 02/02/2024] [Accepted: 02/11/2024] [Indexed: 02/25/2024] Open
Abstract
Cystic fibrosis (CF) is a genetic disorder caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR), a selective anion channel expressed in the epithelium of various organs. The most frequent mutation is F508del. This mutation leads to a misfolded CFTR protein quickly degraded via ubiquitination in the endoplasmic reticulum. Although preventing ubiquitination stabilizes the protein, functionality is not restored due to impaired plasma membrane transport. However, inhibiting the ubiquitination process can improve the effectiveness of correctors which act as chemical chaperones, facilitating F508del CFTR trafficking to the plasma membrane. Previous studies indicate a crosstalk between SUMOylation and ubiquitination in the regulation of CFTR. In this study, we investigated the potential of inhibiting SUMOylation to increase the effects of correctors and enhance the rescue of the F508del mutant across various cell models. In the widely used CFBE41o-cell line expressing F508del-CFTR, inhibiting SUMOylation substantially boosted F508del expression, thereby increasing the efficacy of correctors. Interestingly, this outcome did not result from enhanced stability of the mutant channel, but rather from augmented cytomegalovirus (CMV) promoter-mediated gene expression of F508del-CFTR. Notably, CFTR regulated by endogenous promoters in multiple cell lines or patient cells was not influenced by SUMOylation inhibitors.
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Affiliation(s)
- Christian Borgo
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy; (C.B.); (C.D.)
| | - Claudio D’Amore
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy; (C.B.); (C.D.)
| | - Valeria Capurro
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147 Genova, Italy; (V.C.); (V.T.); (N.P.)
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147 Genova, Italy; (V.C.); (V.T.); (N.P.)
| | - Nicoletta Pedemonte
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147 Genova, Italy; (V.C.); (V.T.); (N.P.)
| | | | - Mauro Salvi
- Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy; (C.B.); (C.D.)
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Ferreira FC, Buarque CD, Lopes-Pacheco M. Organic Synthesis and Current Understanding of the Mechanisms of CFTR Modulator Drugs Ivacaftor, Tezacaftor, and Elexacaftor. Molecules 2024; 29:821. [PMID: 38398574 PMCID: PMC10891718 DOI: 10.3390/molecules29040821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2023] [Revised: 02/02/2024] [Accepted: 02/06/2024] [Indexed: 02/25/2024] Open
Abstract
The monogenic rare disease Cystic Fibrosis (CF) is caused by mutations in the gene encoding the CF transmembrane conductance (CFTR) protein, an anion channel expressed at the apical plasma membrane of epithelial cells. The discovery and subsequent development of CFTR modulators-small molecules acting on the basic molecular defect in CF-have revolutionized the standard of care for people with CF (PwCF), thus drastically improving their clinical features, prognosis, and quality of life. Currently, four of these drugs are approved for clinical use: potentiator ivacaftor (VX-770) alone or in combination with correctors lumacaftor, (VX-809), tezacaftor (VX-661), and elexacaftor (VX-445). Noteworthily, the triple combinatorial therapy composed of ivacaftor, tezacaftor, and elexacaftor constitutes the most effective modulator therapy nowadays for the majority of PwCF. In this review, we exploit the organic synthesis of ivacaftor, tezacaftor, and elexacaftor by providing a retrosynthetic drug analysis for these CFTR modulators. Furthermore, we describe the current understanding of the mechanisms of action (MoA's) of these compounds by discussing several studies that report the key findings on the molecular mechanisms underlying their action on the CFTR protein.
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Affiliation(s)
- Filipa C. Ferreira
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
| | - Camilla D. Buarque
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro 22435-900, RJ, Brazil
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, 1749-016 Lisbon, Portugal
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Riepe C, Wąchalska M, Deol KK, Amaya AK, Porteus MH, Olzmann JA, Kopito RR. Small-molecule correctors divert CFTR-F508del from ERAD by stabilizing sequential folding states. Mol Biol Cell 2024; 35:ar15. [PMID: 38019608 PMCID: PMC10881158 DOI: 10.1091/mbc.e23-08-0336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 11/13/2023] [Accepted: 11/20/2023] [Indexed: 12/01/2023] Open
Abstract
Over 80% of people with cystic fibrosis (CF) carry the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride ion channel at the apical plasma membrane (PM) of epithelial cells. F508del impairs CFTR folding causing it to be destroyed by endoplasmic reticulum associated degradation (ERAD). Small-molecule correctors, which act as pharmacological chaperones to divert CFTR-F508del from ERAD, are the primary strategy for treating CF, yet corrector development continues with only a rudimentary understanding of how ERAD targets CFTR-F508del. We conducted genome-wide CRISPR/Cas9 knockout screens to systematically identify the molecular machinery that underlies CFTR-F508del ERAD. Although the ER-resident ubiquitin ligase, RNF5 was the top E3 hit, knocking out RNF5 only modestly reduced CFTR-F508del degradation. Sublibrary screens in an RNF5 knockout background identified RNF185 as a redundant ligase and demonstrated that CFTR-F508del ERAD is robust. Gene-drug interaction experiments illustrated that correctors tezacaftor (VX-661) and elexacaftor (VX-445) stabilize sequential, RNF5-resistant folding states. We propose that binding of correctors to nascent CFTR-F508del alters its folding landscape by stabilizing folding states that are not substrates for RNF5-mediated ubiquitylation.
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Affiliation(s)
- Celeste Riepe
- Department of Biology, Stanford University, Stanford, CA 94305
| | - Magda Wąchalska
- Department of Biology, Stanford University, Stanford, CA 94305
| | - Kirandeep K. Deol
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720
- Chan Zuckerberg Biohub Network, San Francisco, CA 94158
| | - Anais K. Amaya
- Department of Pediatrics, Stanford University, Stanford, CA 94305
| | | | - James A. Olzmann
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA 94720
- Chan Zuckerberg Biohub Network, San Francisco, CA 94158
| | - Ron R. Kopito
- Department of Biology, Stanford University, Stanford, CA 94305
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Krasnova M, Efremova A, Mokrousova D, Bukharova T, Kashirskaya N, Kutsev S, Kondratyeva E, Goldshtein D. Advances in the Study of Common and Rare CFTR Complex Alleles Using Intestinal Organoids. J Pers Med 2024; 14:129. [PMID: 38392563 PMCID: PMC10890655 DOI: 10.3390/jpm14020129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/15/2024] [Accepted: 01/19/2024] [Indexed: 02/24/2024] Open
Abstract
Complex alleles (CAs) arise when two or more nucleotide variants are present on a single allele. CAs of the CFTR gene complicate the cystic fibrosis diagnosis process, classification of pathogenic variants, and determination of the clinical picture of the disease and increase the need for additional studies to determine their pathogenicity and modulatory effect in response to targeted therapy. For several different populations around the world, characteristic CAs of the CFTR gene have been discovered, although in general the prevalence and pathogenicity of CAs have not been sufficiently studied. This review presents examples of using intestinal organoid models for assessments of the two most common and two rare CFTR CAs in individuals with cystic fibrosis in Russia.
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Affiliation(s)
- Maria Krasnova
- Research Centre for Medical Genetics, Moscow 115522, Russia
| | - Anna Efremova
- Research Centre for Medical Genetics, Moscow 115522, Russia
| | | | | | - Nataliya Kashirskaya
- Research Centre for Medical Genetics, Moscow 115522, Russia
- Moscow Regional Research and Clinical Institute ("MONIKI"), Schepkina Street, 61/2, 1, Moscow 129110, Russia
| | - Sergey Kutsev
- Research Centre for Medical Genetics, Moscow 115522, Russia
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da Silva LVRF, Athanazio RA, Tonon CR, Ferreira JC, Tanni SE. Use of elexacaftor+tezacaftor+ivacaftor in individuals with cystic fibrosis and at least one F508del allele: a systematic review and meta-analysis. J Bras Pneumol 2024; 49:e20230187. [PMID: 38198345 PMCID: PMC10760416 DOI: 10.36416/1806-3756/e20230187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 08/11/2023] [Indexed: 01/12/2024] Open
Abstract
OBJECTIVE To evaluate the effect of treatment with the combination of three cystic fibrosis transmembrane conductance regulator (CFTR) modulators-elexacaftor+tezacaftor+ivacaftor (ETI)-on important clinical endpoints in individuals with cystic fibrosis. METHODS This was a systematic review and meta-analysis of randomized clinical trials that compared the use of ETI in individuals with CF and at least one F508del allele with that of placebo or with an active comparator such as other combinations of CFTR modulators, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations and the Patients of interest, Intervention to be studied, Comparison of interventions, and Outcome of interest (PICO) methodology. We searched the following databases: MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov from their inception to December 26th, 2022. The risk of bias was assessed using the Cochrane risk-of-bias tool, and the quality of evidence was based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE). RESULTS We retrieved 54 studies in the primary search. Of these, 6 met the inclusion criteria and were analyzed (1,127 patients; 577 and 550 in the intervention and control groups, respectively). The meta-analysis revealed that the use of ETI increased FEV1% [risk difference (RD), +10.47%; 95% CI, 6.88-14.06], reduced the number of acute pulmonary exacerbations (RD, -0.16; 95% CI, -0.28 to -0.04), and improved quality of life (RD, +14.93; 95% CI, 9.98-19.89) and BMI (RD, +1.07 kg/m2; 95% CI, 0.90-1.25). Adverse events did not differ between groups (RD, -0.03; 95% CI, -0.08 to 0.01), and none of the studies reported deaths. CONCLUSIONS Our findings demonstrate that ETI treatment substantially improves clinically significant, patient-centered outcomes.
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Affiliation(s)
- Luiz Vicente Ribeiro Ferreira da Silva
- . Unidade de Pneumologia Pediátrica, Instituto da Criança e do Adolescente, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | - Rodrigo Abensur Athanazio
- . Divisão de Pneumologia, Instituto do Coração - InCor - Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | | | - Juliana Carvalho Ferreira
- . Divisão de Pneumologia, Instituto do Coração - InCor - Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo (SP) Brasil
| | - Suzana Erico Tanni
- . Departamento de Clínica Médica, Faculdade de Medicina de Botucatu, Botucatu, (SP) Brasil
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Kamada Y, Tateishi H, Nakayamada U, Hinata D, Iwasaki A, Zhu J, Fukuda R, Okiyoneda T. UBE3C Facilitates the ER-Associated and Peripheral Degradation of Misfolded CFTR. Cells 2023; 12:2741. [PMID: 38067172 PMCID: PMC10706245 DOI: 10.3390/cells12232741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 11/24/2023] [Accepted: 11/28/2023] [Indexed: 12/18/2023] Open
Abstract
The ubiquitin E3 ligase UBE3C promotes the proteasomal degradation of cytosolic proteins and endoplasmic reticulum (ER) membrane proteins. UBE3C is proposed to function downstream of the RNF185/MBRL ER-associated degradation (ERAD) branch, contributing to the ERAD of select membrane proteins. Here, we report that UBE3C facilitates the ERAD of misfolded CFTR, even in the absence of both RNF185 and its functional ortholog RNF5 (RNF5/185). Unlike RNF5/185, UBE3C had a limited impact on the ubiquitination of misfolded CFTR. UBE3C knockdown (KD) resulted in an additional increase in the functional ∆F508-CFTR channels on the plasma membrane when combined with the RNF5/185 ablation, particularly in the presence of clinically used CFTR modulators. Interestingly, although UBE3C KD failed to attenuate the ERAD of insig-1, it reduced the ERAD of misfolded ∆Y490-ABCB1 and increased cell surface expression. UBE3C KD also stabilized the mature form of ∆F508-CFTR and increased the cell surface level of T70-CFTR, a class VI CFTR mutant. These results suggest that UBE3C plays a vital role in the ERAD of misfolded CFTR and ABCB1, even within the RNF5/185-independent ERAD pathway, and it may also be involved in maintaining the peripheral quality control of CFTR.
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Affiliation(s)
| | | | | | | | | | | | | | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1330, Japan; (Y.K.); (H.T.); (U.N.); (D.H.); (A.I.); (J.Z.); (R.F.)
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11
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Riepe C, Wąchalska M, Deol KK, Amaya AK, Porteus MH, Olzmann JA, Kopito RR. Small molecule correctors divert CFTR-F508del from ERAD by stabilizing sequential folding states. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.15.556420. [PMID: 37745470 PMCID: PMC10515913 DOI: 10.1101/2023.09.15.556420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
Over 80% of people with cystic fibrosis (CF) carry the F508del mutation in the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride ion channel at the apical plasma membrane (PM) of epithelial cells. F508del impairs CFTR folding causing it to be destroyed by endoplasmic reticulum associated degradation (ERAD). Small molecule correctors, which act as pharmacological chaperones to divert CFTR-F508del from ERAD, are the primary strategy for treating CF, yet corrector development continues with only a rudimentary understanding of how ERAD targets CFTR-F508del. We conducted genome-wide CRISPR/Cas9 knockout screens to systematically identify the molecular machinery that underlies CFTR-F508del ERAD. Although the ER-resident ubiquitin ligase, RNF5 was the top E3 hit, knocking out RNF5 only modestly reduced CFTR-F508del degradation. Sublibrary screens in an RNF5 knockout background identified RNF185 as a redundant ligase, demonstrating that CFTR-F508del ERAD is highly buffered. Gene-drug interaction experiments demonstrated that correctors tezacaftor (VX-661) and elexacaftor (VX-445) stabilize sequential, RNF5-resistant folding states. We propose that binding of correctors to nascent CFTR-F508del alters its folding landscape by stabilizing folding states that are not substrates for RNF5-mediated ubiquitylation.
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Affiliation(s)
- Celeste Riepe
- Department of Biology, Stanford University, Stanford, CA, USA 94305
| | - Magda Wąchalska
- Department of Biology, Stanford University, Stanford, CA, USA 94305
| | - Kirandeep K. Deol
- Department of Molecular and Cell Biology, University of California, Berkeley, CA USA 94720
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA USA 94720
- Chan Zuckerberg Biohub, San Francisco, CA, USA 94158
| | - Anais K. Amaya
- Department of Pediatrics, Stanford University, Stanford, CA, USA 94305
| | | | - James A. Olzmann
- Department of Molecular and Cell Biology, University of California, Berkeley, CA USA 94720
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, CA USA 94720
- Chan Zuckerberg Biohub, San Francisco, CA, USA 94158
| | - Ron R. Kopito
- Department of Biology, Stanford University, Stanford, CA, USA 94305
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12
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Taniguchi S, Ono Y, Doi Y, Taniguchi S, Matsuura Y, Iwasaki A, Hirata N, Fukuda R, Inoue K, Yamaguchi M, Tashiro A, Egami D, Aoki S, Kondoh Y, Honda K, Osada H, Kumeta H, Saio T, Okiyoneda T. Identification of α-Tocopherol succinate as an RFFL-substrate interaction inhibitor inducing peripheral CFTR stabilization and apoptosis. Biochem Pharmacol 2023; 215:115730. [PMID: 37543348 DOI: 10.1016/j.bcp.2023.115730] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/06/2023] [Accepted: 07/31/2023] [Indexed: 08/07/2023]
Abstract
The E3 ubiquitin ligase RFFL is an apoptotic inhibitor highly expressed in cancers and its knockdown suppresses cancer cell growth and sensitizes to chemotherapy. RFFL also participates in peripheral protein quality control which removes the functional cell surface ΔF508-CFTR channel and reduces the efficacy of pharmaceutical therapy for cystic fibrosis (CF). Although RFFL inhibitors have therapeutic potential for both cancer and CF, they remain undiscovered. Here, a chemical array screening has identified α-tocopherol succinate (αTOS) as an RFFL ligand. NMR analysis revealed that αTOS directly binds to RFFL's substrate-binding region without affecting the E3 enzymatic activity. Consequently, αTOS inhibits the RFFL-substrate interaction, ΔF508-CFTR ubiquitination and elimination from the plasma membrane of epithelial cells, resulting in the increased functional CFTR channel. Among the α-tocopherol (αTOL) analogs we tested, only αTOS inhibited the RFFL-substrate interaction and increased the cell surface ΔF508-CFTR, depending on RFFL expression. Similarly, the unique proapoptotic effect of αTOS was dependent on RFFL expression. Thus, unlike other αTOL analogs, αTOS acts as an RFFL protein-protein interaction inhibitor which may explain its unique biological properties among αTOL analogs. Moreover, αTOS may act as a CFTR stabilizer, a novel class of drugs that extend cell surface ΔF508-CFTR lifetime.
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Affiliation(s)
- Sachiho Taniguchi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Yuji Ono
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Yukako Doi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Shogo Taniguchi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Yuta Matsuura
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Ayuka Iwasaki
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Noriaki Hirata
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Ryosuke Fukuda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan
| | - Keitaro Inoue
- Department of Bioscience and Bioinformatics, Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology, Fukuoka 820-8502, Japan
| | - Miho Yamaguchi
- Department of Bioscience and Bioinformatics, Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology, Fukuoka 820-8502, Japan
| | - Anju Tashiro
- Department of Bioscience and Bioinformatics, Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology, Fukuoka 820-8502, Japan
| | - Daichi Egami
- Department of Bioscience and Bioinformatics, Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology, Fukuoka 820-8502, Japan
| | - Shunsuke Aoki
- Department of Bioscience and Bioinformatics, Graduate School of Computer Science and Systems Engineering, Kyushu Institute of Technology, Fukuoka 820-8502, Japan
| | - Yasumitsu Kondoh
- Chemical Resource Development Unit, RIKEN Center for Sustainable Resource Science, Saitama 351-0198, Japan
| | - Kaori Honda
- Chemical Resource Development Unit, RIKEN Center for Sustainable Resource Science, Saitama 351-0198, Japan
| | - Hiroyuki Osada
- Chemical Resource Development Unit, RIKEN Center for Sustainable Resource Science, Saitama 351-0198, Japan
| | - Hiroyuki Kumeta
- Faculty of Advanced Life Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Tomohide Saio
- Institute of Advanced Medical Sciences, Tokushima University, Tokushima 770-8503, Japan
| | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1337, Japan.
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13
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Oliver KE, Carlon MS, Pedemonte N, Lopes-Pacheco M. The revolution of personalized pharmacotherapies for cystic fibrosis: what does the future hold? Expert Opin Pharmacother 2023; 24:1545-1565. [PMID: 37379072 PMCID: PMC10528905 DOI: 10.1080/14656566.2023.2230129] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/16/2023] [Accepted: 06/23/2023] [Indexed: 06/29/2023]
Abstract
INTRODUCTION Cystic fibrosis (CF), a potentially fatal genetic disease, is caused by loss-of-function mutations in the gene encoding for the CFTR chloride/bicarbonate channel. Modulator drugs rescuing mutant CFTR traffic and function are now in the clinic, providing unprecedented breakthrough therapies for people with CF (PwCF) carrying specific genotypes. However, several CFTR variants are unresponsive to these therapies. AREA COVERED We discussed several therapeutic approaches that are under development to tackle the fundamental cause of CF, including strategies targeting defective CFTR mRNA and/or protein expression and function. Alternatively, defective chloride secretion and dehydration in CF epithelia could be restored by exploiting pharmacological modulation of alternative targets, i.e., ion channels/transporters that concur with CFTR to maintain the airway surface liquid homeostasis (e.g., ENaC, TMEM16A, SLC26A4, SLC26A9, and ATP12A). Finally, we assessed progress and challenges in the development of gene-based therapies to replace or correct the mutant CFTR gene. EXPERT OPINION CFTR modulators are benefiting many PwCF responsive to these drugs, yielding substantial improvements in various clinical outcomes. Meanwhile, the CF therapy development pipeline continues to expand with the development of novel CFTR modulators and alternative therapeutic strategies with the ultimate goal of providing effective therapies for all PwCF in the foreseeable future.
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Affiliation(s)
- Kathryn E. Oliver
- Department of Pediatrics, Emory University School of Medicine, Atlanta, Georgia, USA
- Center for Cystic Fibrosis and Airways Disease Research, Emory University and Children’s Healthcare of Atlanta, Atlanta, Georgia, USA
| | - Marianne S. Carlon
- Laboratory of Respiratory Diseases and Thoracic Surgery (BREATHE), Department of Chronic Diseases and Metabolism, KU Leuven, Leuven, Belgium
- Center for Molecular Medicine, KU Leuven, Leuven, Belgium
| | | | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
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14
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Bongiorno R, Ludovico A, Moran O, Baroni D. Elexacaftor Mediates the Rescue of F508del CFTR Functional Expression Interacting with MSD2. Int J Mol Sci 2023; 24:12838. [PMID: 37629017 PMCID: PMC10454486 DOI: 10.3390/ijms241612838] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Revised: 08/09/2023] [Accepted: 08/11/2023] [Indexed: 08/27/2023] Open
Abstract
Cystic fibrosis (CF) is one of the most frequent lethal autosomal recessive diseases affecting the Caucasian population. It is caused by loss of function variants of the cystic fibrosis transmembrane conductance regulator (CFTR), a membrane protein located on the apical side of epithelial cells. The most prevalent CF-causing mutation, the deletion of phenylalanine at position 508 (F508del), is characterized by folding and trafficking defects, resulting in the decreased functional expression of the protein on the plasma membrane. Two classes of small-molecule modulators, termed potentiators and correctors, respectively, have been developed to rescue either the gating or the cellular processing of defective F508del CFTR. Kaftrio, a next-generation triple-combination drug, consisting of the potentiator ivacaftor (VX770) and the two correctors tezacaftor (VX661) and elexacaftor (VX445), has been demonstrated to be a life-changing therapeutic modality for the majority of people with CF worldwide. While the mechanism of action of VX770 and VX661 is almost known, the precise mechanism of action and binding site of VX445 have not been conclusively determined. We investigated the activity of VX445 on mutant F508del to identify the protein domains whose expression is mostly affected by this corrector and to disclose its mechanisms of action. Our biochemical analyses revealed that VX445 specifically improves the expression and the maturation of MSD2, heterologously expressed in HEK 293 cells, and confirmed that its effect on the functional expression of defective F508del CFTR is additive either with type I or type II CFTR correctors. We are confident that our study will help to make a step forward in the comprehension of the etiopathology of the CF disease, as well as to give new information for the development and testing of combinations of even more effective correctors able to target mutation-specific defects of the CFTR protein.
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Affiliation(s)
| | | | | | - Debora Baroni
- Istituto di Biofisica, CNR, Via De Marini, 6, 16149 Genova, Italy; (R.B.); (A.L.); (O.M.)
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15
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Graeber SY, Balázs A, Ziegahn N, Rubil T, Vitzthum C, Piehler L, Drescher M, Seidel K, Rohrbach A, Röhmel J, Thee S, Duerr J, Mall MA, Stahl M. Personalized CFTR Modulator Therapy for G85E and N1303K Homozygous Patients with Cystic Fibrosis. Int J Mol Sci 2023; 24:12365. [PMID: 37569738 PMCID: PMC10418744 DOI: 10.3390/ijms241512365] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2023] [Revised: 07/28/2023] [Accepted: 07/31/2023] [Indexed: 08/13/2023] Open
Abstract
CFTR modulator therapy with elexacaftor/tezacaftor/ivacaftor (ETI) has been approved for people with CF and at least one F508del allele in Europe. In the US, the ETI label has been expanded to 177 rare CFTR mutations responsive in Fischer rat thyroid cells, including G85E, but not N1303K. However, knowledge on the effect of ETI on G85E or N1303K CFTR function remains limited. In vitro effects of ETI were measured in primary human nasal epithelial cultures (pHNECs) of a G85E homozygous patient and an N1303K homozygous patient. Effects of ETI therapy in vivo in these patients were assessed using clinical outcomes, including multiple breath washout and lung MRI, and the CFTR biomarkers sweat chloride concentration (SCC), nasal potential difference (NPD) and intestinal current measurement (ICM), before and after initiation of ETI. ETI increased CFTR-mediated chloride transport in G85E/G85E and N1303K/N1303K pHNECs. In the G85E/G85E and the N1303K/N1303K patient, we observed an improvement in lung function, SCC, and CFTR function in the respiratory and rectal epithelium after initiation of ETI. The approach of combining preclinical in vitro testing with subsequent in vivo verification can facilitate access to CFTR modulator therapy and enhance precision medicine for patients carrying rare CFTR mutations.
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Affiliation(s)
- Simon Y. Graeber
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
- Berlin Institute of Health (BIH) at Charité–Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Anita Balázs
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Niklas Ziegahn
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
| | - Tihomir Rubil
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Constanze Vitzthum
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Linus Piehler
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Marika Drescher
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Kathrin Seidel
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Alexander Rohrbach
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Jobst Röhmel
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
- Berlin Institute of Health (BIH) at Charité–Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Stephanie Thee
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
- Berlin Institute of Health (BIH) at Charité–Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Julia Duerr
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
| | - Marcus A. Mall
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
- Berlin Institute of Health (BIH) at Charité–Universitätsmedizin Berlin, 10117 Berlin, Germany
| | - Mirjam Stahl
- Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Charité–Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, 13353 Berlin, Germany
- German Centre for Lung Research (DZL), Associated Partner Site, 13353 Berlin, Germany
- Berlin Institute of Health (BIH) at Charité–Universitätsmedizin Berlin, 10117 Berlin, Germany
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16
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Brusa I, Sondo E, Pesce E, Tomati V, Gioia D, Falchi F, Balboni B, Ortega Martínez JA, Veronesi M, Romeo E, Margaroli N, Recanatini M, Girotto S, Pedemonte N, Roberti M, Cavalli A. Innovative Strategy toward Mutant CFTR Rescue in Cystic Fibrosis: Design and Synthesis of Thiadiazole Inhibitors of the E3 Ligase RNF5. J Med Chem 2023. [PMID: 37440686 PMCID: PMC10388311 DOI: 10.1021/acs.jmedchem.3c00608] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/15/2023]
Abstract
In cystic fibrosis (CF), deletion of phenylalanine 508 (F508del) in the CF transmembrane conductance regulator (CFTR) is associated to misfolding and defective gating of the mutant channel. One of the most promising CF drug targets is the ubiquitin ligase RNF5, which promotes F508del-CFTR degradation. Recently, the first ever reported inhibitor of RNF5 was discovered, i.e., the 1,2,4-thiadiazol-5-ylidene inh-2. Here, we designed and synthesized a series of new analogues to explore the structure-activity relationships (SAR) of this class of compounds. SAR efforts ultimately led to compound 16, which showed a greater F508del-CFTR corrector activity than inh-2, good tolerability, and no toxic side effects. Analogue 16 increased the basal level of autophagy similar to what has been described with RNF5 silencing. Furthermore, co-treatment with 16 significantly improved the F508del-CFTR rescue induced by the triple combination elexacaftor/tezacaftor/ivacaftor in CFBE41o- cells. These findings validate the 1,2,4-thiadiazolylidene scaffold for the discovery of novel RNF5 inhibitors and provide evidence to pursue this unprecedented strategy for the treatment of CF.
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Affiliation(s)
- Irene Brusa
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Elvira Sondo
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Emanuela Pesce
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Dario Gioia
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Federico Falchi
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Beatrice Balboni
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | | | - Marina Veronesi
- Structural Biophysics and Translational Pharmacology Facility, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Elisa Romeo
- Structural Biophysics and Translational Pharmacology Facility, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Natasha Margaroli
- Structural Biophysics and Translational Pharmacology Facility, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Maurizio Recanatini
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
| | - Stefania Girotto
- Structural Biophysics and Translational Pharmacology Facility, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | | | - Marinella Roberti
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
| | - Andrea Cavalli
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
- Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
- Centre Européen de Calcul Atomique et Moléculaire, EPFL CECAM, 1015 Lousanne, Switzerland
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17
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Kleinfelder K, Villella VR, Hristodor AM, Laudanna C, Castaldo G, Amato F, Melotti P, Sorio C. Theratyping of the Rare CFTR Genotype A559T in Rectal Organoids and Nasal Cells Reveals a Relevant Response to Elexacaftor (VX-445) and Tezacaftor (VX-661) Combination. Int J Mol Sci 2023; 24:10358. [PMID: 37373505 DOI: 10.3390/ijms241210358] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 06/12/2023] [Accepted: 06/15/2023] [Indexed: 06/29/2023] Open
Abstract
Despite the promising results of new CFTR targeting drugs designed for the recovery of F508del- and class III variants activity, none of them have been approved for individuals with selected rare mutations, because uncharacterized CFTR variants lack information associated with the ability of these compounds in recovering their molecular defects. Here we used both rectal organoids (colonoids) and primary nasal brushed cells (hNEC) derived from a CF patient homozygous for A559T (c.1675G>A) variant to evaluate the responsiveness of this pathogenic variant to available CFTR targeted drugs that include VX-770, VX-809, VX-661 and VX-661 combined with VX-445. A559T is a rare mutation, found in African-Americans people with CF (PwCF) with only 85 patients registered in the CFTR2 database. At present, there is no treatment approved by FDA (U.S. Food and Drug Administration) for this genotype. Short-circuit current (Isc) measurements indicate that A559T-CFTR presents a minimal function. The acute addition of VX-770 following CFTR activation by forskolin had no significant increment of baseline level of anion transport in both colonoids and nasal cells. However, the combined treatment, VX-661-VX-445, significantly increases the chloride secretion in A559T-colonoids monolayers and hNEC, reaching approximately 10% of WT-CFTR function. These results were confirmed by forskolin-induced swelling assay and by western blotting in rectal organoids. Overall, our data show a relevant response to VX-661-VX-445 in rectal organoids and hNEC with CFTR genotype A559T/A559T. This could provide a strong rationale for treating patients carrying this variant with VX-661-VX-445-VX-770 combination.
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Affiliation(s)
- Karina Kleinfelder
- Cystic Fibrosis Laboratory "D. Lissandrini", Department of Medicine, Division of General Pathology, University of Verona, 37134 Verona, Italy
| | - Valeria Rachela Villella
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, 80138 Napoli, Italy
- CEINGE-Advanced Biotechnologies Franco Salvatore, 80145 Naples, Italy
| | - Anca Manuela Hristodor
- Cystic Fibrosis Centre, Azienda Ospedaliera Universitaria Integrata Verona, 37126 Verona, Italy
| | - Carlo Laudanna
- Cystic Fibrosis Laboratory "D. Lissandrini", Department of Medicine, Division of General Pathology, University of Verona, 37134 Verona, Italy
| | - Giuseppe Castaldo
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, 80138 Napoli, Italy
- CEINGE-Advanced Biotechnologies Franco Salvatore, 80145 Naples, Italy
| | - Felice Amato
- Department of Molecular Medicine and Medical Biotechnologies, University of Naples Federico II, 80138 Napoli, Italy
| | - Paola Melotti
- Cystic Fibrosis Centre, Azienda Ospedaliera Universitaria Integrata Verona, 37126 Verona, Italy
| | - Claudio Sorio
- Cystic Fibrosis Laboratory "D. Lissandrini", Department of Medicine, Division of General Pathology, University of Verona, 37134 Verona, Italy
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18
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Amistadi S, Maule G, Ciciani M, Ensinck MM, De Keersmaecker L, Ramalho AS, Guidone D, Buccirossi M, Galietta LJV, Carlon MS, Cereseto A. Functional restoration of a CFTR splicing mutation through RNA delivery of CRISPR adenine base editor. Mol Ther 2023; 31:1647-1660. [PMID: 36895161 PMCID: PMC10277887 DOI: 10.1016/j.ymthe.2023.03.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2022] [Revised: 01/07/2023] [Accepted: 03/03/2023] [Indexed: 03/11/2023] Open
Abstract
Cystic fibrosis (CF) is a genetic disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The 2789+5G>A CFTR mutation is a quite frequent defect causing an aberrant splicing and a non-functional CFTR protein. Here we used a CRISPR adenine base editing (ABE) approach to correct the mutation in the absence of DNA double-strand breaks (DSB). To select the strategy, we developed a minigene cellular model reproducing the 2789+5G>A splicing defect. We obtained up to 70% editing in the minigene model by adapting the ABE to the PAM sequence optimal for targeting 2789+5G>A with a SpCas9-NG (NG-ABE). Nonetheless, the on-target base correction was accompanied by secondary (bystander) A-to-G conversions in nearby nucleotides, which affected the wild-type CFTR splicing. To decrease the bystander edits, we used a specific ABE (NG-ABEmax), which was delivered as mRNA. The NG-ABEmax RNA approach was validated in patient-derived rectal organoids and bronchial epithelial cells showing sufficient gene correction to recover the CFTR function. Finally, in-depth sequencing revealed high editing precision genome-wide and allele-specific correction. Here we report the development of a base editing strategy to precisely repair the 2789+5G>A mutation resulting in restoration of the CFTR function, while reducing bystander and off-target activities.
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Affiliation(s)
- Simone Amistadi
- University of Trento, Department of Computational, Cellular and Integrative Biology, Laboratory of Molecular Virology, 38123 Trento, Italy
| | - Giulia Maule
- University of Trento, Department of Computational, Cellular and Integrative Biology, Laboratory of Molecular Virology, 38123 Trento, Italy.
| | - Matteo Ciciani
- University of Trento, Department of Computational, Cellular and Integrative Biology, Laboratory of Molecular Virology, 38123 Trento, Italy
| | - Marjolein M Ensinck
- KU Leuven, Department of Pharmaceutical and Pharmacological Sciences, Laboratory for Molecular Virology and Gene Therapy, 3000 Leuven, Belgium
| | - Liesbeth De Keersmaecker
- KU Leuven, Department of Pharmaceutical and Pharmacological Sciences, Laboratory for Molecular Virology and Gene Therapy, 3000 Leuven, Belgium
| | - Anabela S Ramalho
- CF Research Lab, Woman and Child Unit, Department of Development and Regeneration, KU Leuven, 3000 Leuven, Belgium
| | - Daniela Guidone
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy
| | | | - Luis J V Galietta
- Telethon Institute of Genetics and Medicine, 80078 Pozzuoli, Italy; Department of Translational Medical Sciences, University of Napoli "Federico II," 80138 Napoli, Italy
| | - Marianne S Carlon
- KU Leuven, Department of Pharmaceutical and Pharmacological Sciences, Laboratory for Molecular Virology and Gene Therapy, 3000 Leuven, Belgium; KU Leuven, Department of Chronic Diseases and Metabolism, BREATHE Laboratory, 3000 Leuven, Belgium
| | - Anna Cereseto
- University of Trento, Department of Computational, Cellular and Integrative Biology, Laboratory of Molecular Virology, 38123 Trento, Italy.
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19
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Barros P, Matos AM, Matos P, Jordan P. YES1 Kinase Mediates the Membrane Removal of Rescued F508del-CFTR in Airway Cells by Promoting MAPK Pathway Activation via SHC1. Biomolecules 2023; 13:949. [PMID: 37371529 DOI: 10.3390/biom13060949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 05/26/2023] [Accepted: 06/01/2023] [Indexed: 06/29/2023] Open
Abstract
Recent developments in CFTR modulator drugs have had a significant transformational effect on the treatment of individuals with Cystic Fibrosis (CF) who carry the most frequent F508del-CFTR mutation in at least one allele. However, the clinical effects of these revolutionary drugs remain limited by their inability to fully restore the plasma membrane (PM) stability of the rescued mutant channels. Here, we shed new light on the molecular mechanisms behind the reduced half-life of rescued F508del-CFTR at the PM of airway cells. We describe that YES1 protein kinase is enriched in F508del-CFTR protein PM complexes, and that its interaction with rescued channels is mediated and dependent on the adaptor protein YAP1. Moreover, we show that interference with this complex, either by depletion of one of these components or inhibiting YES1 activity, is sufficient to significantly improve the abundance and stability of modulator-rescued F508del-CFTR at the surface of airway cells. In addition, we found that this effect was mediated by a decreased phosphorylation of the scaffold protein SHC1, a key regulator of MAPK pathway activity. In fact, we showed that depletion of SHC1 or inhibition of MAPK pathway signaling was sufficient to improve rescued F508del-CFTR surface levels, whereas an ectopic increase in pathway activation downstream of SHC1, through the use of a constitutively active H-RAS protein, abrogated the stabilizing effect of YES1 inhibition on rescued F508del-CFTR. Taken together, our findings not only provide new mechanistic insights into the regulation of modulator-rescued F508del-CFTR membrane stability, but also open exciting new avenues to be further explored in CF research and treatment.
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Affiliation(s)
- Patrícia Barros
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- BioISI-Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, 1749-016 Lisboa, Portugal
| | - Ana M Matos
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- BioISI-Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, 1749-016 Lisboa, Portugal
| | - Paulo Matos
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- BioISI-Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, 1749-016 Lisboa, Portugal
| | - Peter Jordan
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- BioISI-Biosystems & Integrative Sciences Institute, Faculty of Sciences, University of Lisboa, 1749-016 Lisboa, Portugal
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20
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Taniguchi S, Fukuda R, Okiyoneda T. The multiple ubiquitination mechanisms in CFTR peripheral quality control. Biochem Soc Trans 2023:233016. [PMID: 37140364 DOI: 10.1042/bst20221468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/11/2023] [Accepted: 04/18/2023] [Indexed: 05/05/2023]
Abstract
The cystic fibrosis transmembrane conductance regulator (CFTR) is a cAMP-regulated anion channel, which is expressed on the apical plasma membrane (PM) of epithelial cells. Mutations in the CFTR gene cause cystic fibrosis (CF), one of the most common genetic diseases among Caucasians. Most CF-associated mutations result in misfolded CFTR proteins that are degraded by the endoplasmic reticulum quality control (ERQC) mechanism. However, the mutant CFTR reaching the PM through therapeutic agents is still ubiquitinated and degraded by the peripheral protein quality control (PeriQC) mechanism, resulting in reduced therapeutic efficacy. Moreover, certain CFTR mutants that can reach the PM under physiological conditions are degraded by PeriQC. Thus, it may be beneficial to counteract the selective ubiquitination in PeriQC to enhance therapeutic outcomes for CF. Recently, the molecular mechanisms of CFTR PeriQC have been revealed, and several ubiquitination mechanisms, including both chaperone-dependent and -independent pathways, have been identified. In this review, we will discuss the latest findings related to CFTR PeriQC and propose potential novel therapeutic strategies for CF.
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Affiliation(s)
- Shogo Taniguchi
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1330, Japan
| | - Ryosuke Fukuda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1330, Japan
| | - Tsukasa Okiyoneda
- Department of Biomedical Sciences, School of Biological and Environmental Sciences, Kwansei Gakuin University, Hyogo 669-1330, Japan
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21
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Terlizzi V, Pesce E, Capurro V, Tomati V, Lena M, Pastorino C, Bocciardi R, Zara F, Centrone C, Taccetti G, Castellani C, Pedemonte N. Clinical Consequences and Functional Impact of the Rare S737F CFTR Variant and Its Responsiveness to CFTR Modulators. Int J Mol Sci 2023; 24:ijms24076576. [PMID: 37047546 PMCID: PMC10095403 DOI: 10.3390/ijms24076576] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2023] [Revised: 03/28/2023] [Accepted: 03/30/2023] [Indexed: 04/05/2023] Open
Abstract
S737F is a Cystic Fibrosis (CF) transmembrane conductance regulator (CFTR) missense variant. The aim of our study was to describe the clinical features of a cohort of individuals carrying this variant. In parallel, by exploiting ex vivo functional and molecular analyses on nasal epithelia derived from a subset of S737F carriers, we evaluated its functional impact on CFTR protein as well as its responsiveness to CFTR modulators. We retrospectively collected clinical data of all individuals bearing at least one S737F CFTR variant and followed at the CF Centre of Tuscany region (Italy). Nasal brushing was performed in cooperating individuals. At study end clinical data were available for 10 subjects (mean age: 14 years; range 1–44 years; 3 adult individuals). Five asymptomatic subjects had CF, 2 were CRMS/CFSPID and 3 had an inconclusive diagnosis. Ex vivo analysis on nasal epithelia demonstrated different levels of CF activity. In particular, epithelia derived from asymptomatic CF subjects and from one of the subjects with inconclusive diagnosis showed reduced CFTR activity that could be rescued by treatment with CFTR modulators. On the contrary, in the epithelia derived from the other two individuals with an inconclusive diagnosis, the CFTR-mediated current was similar to that observed in epithelia derived from healthy donors. In vitro functional and biochemical analysis on S737F-CFTR expressed in immortalized bronchial cells highlighted a modest impairment of the channel activity, that was improved by treatment with ivacaftor alone or in combination with tezacaftor/elexacaftor. Our study provide evidence towards the evaluation of CFTR function on ex vivo nasal epithelial cell models as a new assay to help clinicians to classify individuals, in presence of discordance between clinical picture, sweat test and genetic profile.
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Affiliation(s)
- Vito Terlizzi
- Department of Paediatric Medicine, Meyer Children’s Hospital IRCCS, Cystic Fibrosis Regional Reference Center, 50139 Florence, Italy
| | - Emanuela Pesce
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Valeria Capurro
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Mariateresa Lena
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, 16126 Genova, Italy
| | - Cristina Pastorino
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | - Renata Bocciardi
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, 16126 Genova, Italy
| | - Federico Zara
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DINOGMI), University of Genoa, 16126 Genova, Italy
| | - Claudia Centrone
- Diagnostic Genetics Unit, Careggi University Hospital, 50134 Florence, Italy
| | - Giovanni Taccetti
- Department of Paediatric Medicine, Meyer Children’s Hospital IRCCS, Cystic Fibrosis Regional Reference Center, 50139 Florence, Italy
| | - Carlo Castellani
- UOSD Centro Fibrosi Cistica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
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22
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Tümmler B. Post-approval studies with the CFTR modulators Elexacaftor-Tezacaftor—Ivacaftor. Front Pharmacol 2023; 14:1158207. [PMID: 37025483 PMCID: PMC10072268 DOI: 10.3389/fphar.2023.1158207] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 03/07/2023] [Indexed: 03/31/2023] Open
Abstract
Triple combination therapy with the CFTR modulators elexacaftor (ELX), tezacaftor (TEZ) and ivacaftor (IVA) has been qualified as a game changer in cystic fibrosis (CF). We provide an overview of the body of literature on ELX/TEZ/IVA published between November 2019 and February 2023 after approval by the regulators. Recombinant ELX/TEZ/IVA-bound Phe508del CFTR exhibits a wild type conformationin vitro, but in patient’s tissue a CFTR glyoisoform is synthesized that is distinct from the wild type and Phe508del isoforms. ELX/TEZ/IVA therapy improved the quality of life of people with CF in the real-life setting irrespective of their anthropometry and lung function at baseline. ELX/TEZ/IVA improved sinonasal and abdominal disease, lung function and morphology, airway microbiology and the basic defect of impaired epithelial chloride and bicarbonate transport. Pregnancy rates were increasing in women with CF. Side effects of mental status changes deserve particular attention in the future.
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Affiliation(s)
- Burkhard Tümmler
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hannover Medical School, Hannover, Germany
- *Correspondence: Burkhard Tümmler,
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23
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Hwang TC, Braakman I, van der Sluijs P, Callebaut I. Structure basis of CFTR folding, function and pharmacology. J Cyst Fibros 2023; 22 Suppl 1:S5-S11. [PMID: 36216744 DOI: 10.1016/j.jcf.2022.09.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2022] [Revised: 09/19/2022] [Accepted: 09/26/2022] [Indexed: 11/05/2022]
Abstract
The root cause of cystic fibrosis (CF), the most common life-shortening genetic disease in the Caucasian population, is the loss of function of the CFTR protein, which serves as a phosphorylation-activated, ATP-gated anion channel in numerous epithelia-lining tissues. In the past decade, high-throughput drug screening has made a significant stride in developing highly effective CFTR modulators for the treatment of CF. Meanwhile, structural-biology studies have succeeded in solving the high-resolution three-dimensional (3D) structure of CFTR in different conformations. Here, we provide a brief overview of some striking features of CFTR folding, function and pharmacology, in light of its specific structural features within the ABC-transporter superfamily. A particular focus is given to CFTR's first nucleotide-binding domain (NBD1), because folding of NBD1 constitutes a bottleneck in the CFTR protein biogenesis pathway, and ATP binding to this domain plays a unique role in the functional stability of CFTR. Unraveling the molecular basis of CFTR folding, function, and pharmacology would inspire the development of next-generation mutation-specific CFTR modulators.
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Affiliation(s)
- Tzyh-Chang Hwang
- Institute of Pharmacology, School of Medicine, National Yang Ming Chiao Tung University, Taiwan; Department of Medical Pharmacology and Physiology, Dalton Cardiovascular Research Center, University of Missouri, Columbia, MO, USA
| | - Ineke Braakman
- Cellular Protein Chemistry, Bijvoet Centre for Biomolecular Research, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Peter van der Sluijs
- Cellular Protein Chemistry, Bijvoet Centre for Biomolecular Research, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Isabelle Callebaut
- Sorbonne Université, Muséum National d'Histoire Naturelle, UMR CNRS 7590, Institut de Minéralogie, de Physique des Matériaux et de Cosmochimie, IMPMC, 75005 Paris, France.
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24
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Stanke F, Pallenberg ST, Tamm S, Hedtfeld S, Eichhorn EM, Minso R, Hansen G, Welte T, Sauer-Heilborn A, Ringshausen FC, Junge S, Tümmler B, Dittrich AM. Changes in cystic fibrosis transmembrane conductance regulator protein expression prior to and during elexacaftor-tezacaftor-ivacaftor therapy. Front Pharmacol 2023; 14:1114584. [PMID: 36778025 PMCID: PMC9911415 DOI: 10.3389/fphar.2023.1114584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 01/16/2023] [Indexed: 01/28/2023] Open
Abstract
Background: Defects in expression, maturation or function of the epithelial membrane glycoprotein CFTR are causative for the progressive disease cystic fibrosis. Recently, molecular therapeutics that improve CFTR maturation and functional defects have been approved. We aimed to verify whether we could detect an improvement of CFTR protein expression and maturation by triple therapy with elexacaftor-tezacaftor-ivacaftor (ELX/TEZ/IVA). Methods: Rectal suction biopsies of 21 p.Phe508del homozygous or compound heterozygous CF patients obtained pre- and during treatment with ELX/TEZ/IVA were analyzed by CFTR Western blot that was optimized to distinguish CFTR glycoisoforms. Findings: CFTR western immunoblot analysis revealed that-compared to baseline-the levels of CFTR protein increased by at least twofold in eight out of 12 patients upon treatment with ELX/TEZ/IVA compared to baseline (p < 0.02). However, polydispersity of the mutant CFTR protein was lower than that of the fully glycosylated wild type CFTR Golgi isoform, indicating an incompletely glycosylated p.Phe508el CFTR protein isoform C* in patients with CF which persists after ELX/TEZ/IVA treatment. Interpretation: Treatment with ELX/TEZ/IVA increased protein expression by facilitating the posttranslational processing of mutant CFTR but apparently did not succeed in generating the polydisperse spectrum of N-linked oligosaccharides that is characteristic for the wild type CFTR band C glycoisoform. Our results caution that the lower amounts or immature glycosylation of the C* glycoisoform observed in patients' biomaterial might not translate to fully restored function of mutant CFTR necessary for long-term provision of clinical benefit.
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Affiliation(s)
- Frauke Stanke
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hannover Medical School, Hannover, Germany,*Correspondence: Frauke Stanke,
| | - Sophia T. Pallenberg
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Stephanie Tamm
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hannover Medical School, Hannover, Germany
| | - Silke Hedtfeld
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Ella M. Eichhorn
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Rebecca Minso
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Gesine Hansen
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hannover Medical School, Hannover, Germany
| | - Tobias Welte
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hannover Medical School, Hannover, Germany,Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany
| | | | - Felix C. Ringshausen
- Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hannover Medical School, Hannover, Germany,Department of Respiratory Medicine, Hannover Medical School, Hannover, Germany
| | - Sibylle Junge
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany
| | - Burkhard Tümmler
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hannover Medical School, Hannover, Germany
| | - Anna-Maria Dittrich
- Department of Pediatric Pneumology, Allergology and Neonatology, Hannover Medical School, Hannover, Germany,Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), German Center for Lung Research, Hannover Medical School, Hannover, Germany
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25
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Tomati V, Costa S, Capurro V, Pesce E, Pastorino C, Lena M, Sondo E, Di Duca M, Cresta F, Cristadoro S, Zara F, Galietta LJ, Bocciardi R, Castellani C, Lucanto MC, Pedemonte N. Rescue by elexacaftor-tezacaftor-ivacaftor of the G1244E cystic fibrosis mutation's stability and gating defects are dependent on cell background. J Cyst Fibros 2022:S1569-1993(22)01425-4. [DOI: 10.1016/j.jcf.2022.12.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 11/23/2022] [Accepted: 12/13/2022] [Indexed: 12/23/2022]
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26
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Bacalhau M, Ferreira FC, Kmit A, Souza FR, da Silva VD, Pimentel AS, Amaral MD, Buarque CD, Lopes-Pacheco M. Identification of novel F508del-CFTR traffic correctors among triazole derivatives. Eur J Pharmacol 2022; 938:175396. [PMID: 36410419 DOI: 10.1016/j.ejphar.2022.175396] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 11/14/2022] [Accepted: 11/15/2022] [Indexed: 11/21/2022]
Abstract
The most prevalent cystic fibrosis (CF)-causing mutation - F508del - impairs the folding of CFTR protein, resulting in its defective trafficking and premature degradation. Small molecules termed correctors may rescue F508del-CFTR and therefore constitute promising pharmacotherapies acting on the fundamental cause of the disease. Here, we screened a collection of triazole compounds to identify novel F508del-CFTR correctors. The functional primary screen identified four hit compounds (LSO-18, LSO-24, LSO-28, and LSO-39), which were further validated and demonstrated to rescue F508del-CFTR processing, plasma membrane trafficking, and function. To interrogate their mechanism of action (MoA), we examined their additivity to the clinically approved drugs VX-661 and VX-445, low temperature, and genetic revertants of F508del-CFTR. Rescue of F508del-CFTR processing and function by LSO-18, LSO-24, and LSO-28, but not by LSO-39, was additive to VX-661, whereas LSO-28 and LSO-39, but not LSO-18 nor LSO-24, were additive to VX-445. All compounds under investigation demonstrated additive rescue of F508del-CFTR processing and function to low temperature as well as to rescue by genetic revertants G550E and 4RK. Nevertheless, none of these compounds was able to rescue processing nor function of DD/AA-CFTR, and LSO-39 (similarly to VX-661) exhibited no additivity to genetic revertant R1070W. From these findings, we suggest that LSO-39 (like VX-661) has a putative binding site at the NBD1:ICL4 interface, LSO-18 and LSO-24 seem to share the MoA with VX-445, and LSO-28 appears to act by a different MoA. Altogether, these findings represent an encouraging starting point to further exploit this chemical series for the development of novel CFTR correctors.
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Affiliation(s)
- Mafalda Bacalhau
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Filipa C Ferreira
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Arthur Kmit
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Felipe R Souza
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil
| | - Verônica D da Silva
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil
| | - André S Pimentel
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil
| | - Margarida D Amaral
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal
| | - Camilla D Buarque
- Department of Chemistry, Pontifical Catholic University of Rio de Janeiro (PUC-Rio), Rio de Janeiro, Brazil
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisbon, Lisbon, Portugal.
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27
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Fiedorczuk K, Chen J. Molecular structures reveal synergistic rescue of Δ508 CFTR by Trikafta modulators. Science 2022; 378:284-290. [PMID: 36264792 PMCID: PMC9912939 DOI: 10.1126/science.ade2216] [Citation(s) in RCA: 59] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The predominant mutation causing cystic fibrosis, a deletion of phenylalanine 508 (Δ508) in the cystic fibrosis transmembrane conductance regulator (CFTR), leads to severe defects in CFTR biogenesis and function. The advanced therapy Trikafta combines the folding corrector tezacaftor (VX-661), the channel potentiator ivacaftor (VX-770), and the dual-function modulator elexacaftor (VX-445). However, it is unclear how elexacaftor exerts its effects, in part because the structure of Δ508 CFTR is unknown. Here, we present cryo-electron microscopy structures of Δ508 CFTR in the absence and presence of CFTR modulators. When used alone, elexacaftor partially rectified interdomain assembly defects in Δ508 CFTR, but when combined with a type I corrector, did so fully. These data illustrate how the different modulators in Trikafta synergistically rescue Δ508 CFTR structure and function.
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Affiliation(s)
- Karol Fiedorczuk
- Laboratory of Membrane Biology and Biophysics, The Rockefeller University, New York, NY 10065, USA
| | - Jue Chen
- Laboratory of Membrane Biology and Biophysics, The Rockefeller University, New York, NY 10065, USA,Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA,Corresponding author.
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28
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Pharmacological chaperone-rescued cystic fibrosis CFTR-F508del mutant overcomes PRAF2-gated access to endoplasmic reticulum exit sites. Cell Mol Life Sci 2022; 79:530. [PMID: 36167862 DOI: 10.1007/s00018-022-04554-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 09/08/2022] [Accepted: 09/09/2022] [Indexed: 11/03/2022]
Abstract
The endoplasmic reticulum exit of some polytopic plasma membrane proteins (PMPs) is controlled by arginin-based retention motifs. PRAF2, a gatekeeper which recognizes these motifs, was shown to retain the GABAB-receptor GB1 subunit in the ER. We report that PRAF2 can interact on a stoichiometric basis with both wild type and mutant F508del Cystic Fibrosis (CF) Transmembrane Conductance Regulator (CFTR), preventing the access of newly synthesized cargo to ER exit sites. Because of its lower abundance, compared to wild-type CFTR, CFTR-F508del recruitment into COPII vesicles is suppressed by the ER-resident PRAF2. We also demonstrate that some pharmacological chaperones that efficiently rescue CFTR-F508del loss of function in CF patients target CFTR-F508del retention by PRAF2 operating with various mechanisms. Our findings open new therapeutic perspectives for diseases caused by the impaired cell surface trafficking of mutant PMPs, which contain RXR-based retention motifs that might be recognized by PRAF2.
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Berical A, Lee RE, Lu J, Beermann ML, Le Suer JA, Mithal A, Thomas D, Ranallo N, Peasley M, Stuffer A, Bukis K, Seymour R, Harrington J, Coote K, Valley H, Hurley K, McNally P, Mostoslavsky G, Mahoney J, Randell SH, Hawkins FJ. A multimodal iPSC platform for cystic fibrosis drug testing. Nat Commun 2022; 13:4270. [PMID: 35906215 PMCID: PMC9338271 DOI: 10.1038/s41467-022-31854-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Accepted: 07/06/2022] [Indexed: 01/27/2023] Open
Abstract
Cystic fibrosis is a monogenic lung disease caused by dysfunction of the cystic fibrosis transmembrane conductance regulator anion channel, resulting in significant morbidity and mortality. The progress in elucidating the role of CFTR using established animal and cell-based models led to the recent discovery of effective modulators for most individuals with CF. However, a subset of individuals with CF do not respond to these modulators and there is an urgent need to develop novel therapeutic strategies. In this study, we generate a panel of airway epithelial cells using induced pluripotent stem cells from individuals with common or rare CFTR variants representative of three distinct classes of CFTR dysfunction. To measure CFTR function we adapt two established in vitro assays for use in induced pluripotent stem cell-derived airway cells. In both a 3-D spheroid assay using forskolin-induced swelling as well as planar cultures composed of polarized mucociliary airway epithelial cells, we detect genotype-specific differences in CFTR baseline function and response to CFTR modulators. These results demonstrate the potential of the human induced pluripotent stem cell platform as a research tool to study CF and in particular accelerate therapeutic development for CF caused by rare variants.
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Affiliation(s)
- Andrew Berical
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA, 02118, USA
- The Pulmonary Center and Department of Medicine, Boston University and Boston Medical Center, Boston, MA, 02118, USA
| | - Rhianna E Lee
- Marsico Lung Institute and Cystic Fibrosis Research Center, Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Junjie Lu
- Cystic Fibrosis Foundation, Lexington, MA, 02421, USA
| | - Mary Lou Beermann
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA, 02118, USA
| | - Jake A Le Suer
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA, 02118, USA
| | - Aditya Mithal
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA, 02118, USA
| | - Dylan Thomas
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA, 02118, USA
| | - Nicole Ranallo
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA, 02118, USA
| | - Megan Peasley
- Cystic Fibrosis Foundation, Lexington, MA, 02421, USA
| | - Alex Stuffer
- Cystic Fibrosis Foundation, Lexington, MA, 02421, USA
| | | | | | | | - Kevin Coote
- Cystic Fibrosis Foundation, Lexington, MA, 02421, USA
| | | | - Killian Hurley
- Department of Medicine, Royal College of Surgeons in Ireland, Education and Research Centre, Beaumont Hospital, Dublin, Ireland
- Tissue Engineering Research Group, Royal College of Surgeons in Ireland, Dublin, Ireland
| | - Paul McNally
- RCSI University of Medicine and Health Sciences, Dublin, Ireland
- Children's Health Ireland, Dublin, Ireland
| | - Gustavo Mostoslavsky
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA, 02118, USA
| | - John Mahoney
- Cystic Fibrosis Foundation, Lexington, MA, 02421, USA
| | - Scott H Randell
- Marsico Lung Institute and Cystic Fibrosis Research Center, Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
- Department of Cell Biology and Physiology, University of North Carolina at Chapel Hill, Chapel Hill, NC, 27599, USA
| | - Finn J Hawkins
- Center for Regenerative Medicine of Boston University and Boston Medical Center, Boston, MA, 02118, USA.
- The Pulmonary Center and Department of Medicine, Boston University and Boston Medical Center, Boston, MA, 02118, USA.
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A Splice Switch in SIGIRR Causes a Defect of IL-37-Dependent Anti-Inflammatory Activity in Cystic Fibrosis Airway Epithelial Cells. Int J Mol Sci 2022; 23:ijms23147748. [PMID: 35887095 PMCID: PMC9318995 DOI: 10.3390/ijms23147748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 07/05/2022] [Accepted: 07/12/2022] [Indexed: 11/23/2022] Open
Abstract
Cystic fibrosis (CF) is a hereditary disease typically characterized by infection-associated chronic lung inflammation. The persistent activation of toll-like receptor (TLR) signals is considered one of the mechanisms for the CF hyperinflammatory phenotype; however, how negative regulatory signals of TLRs associate with CF inflammation is still elusive. Here, we showed that the cell surface expression of a single immunoglobulin interleukin-1 receptor (IL-1R)-related molecule (SIGIRR), a membrane protein essential for suppressing TLRs- and IL-1R-dependent signals, was remarkably decreased in CF airway epithelial cells compared to non-CF cells. Notably, CF airway epithelial cells specifically and highly expressed a unique, alternative splice isoform of the SIGIRR that lacks exon 8 (Δ8-SIGIRR), which results in the production of a C-terminal truncated form of the SIGIRR. Δ8-SIGIRR was expressed intracellularly, and its over-expression abolished the cell surface expression and function of the full-length SIGIRR (WT-SIGIRR), indicating its dominant-negative effect leading to the deficiency of anti-inflammatory activity in CF cells. Consistently, IL-37, a ligand for the SIGIRR, failed to suppress viral dsRNA analogue poly(I:C)-dependent JNK activation and IL-8 production, confirming the reduction in the functional WT-SIGIRR expression in the CF cells. Together, our studies reveal that SIGIRR-dependent anti-inflammatory activity is defective in CF airway epithelial cells due to the unique splicing switch of the SIGIRR gene and provides the first evidence of IL-37-SIGIRR signaling as a target of CF airway inflammation.
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Braccia C, Christopher JA, Crook OM, Breckels LM, Queiroz RML, Liessi N, Tomati V, Capurro V, Bandiera T, Baldassari S, Pedemonte N, Lilley KS, Armirotti A. CFTR Rescue by Lumacaftor (VX-809) Induces an Extensive Reorganization of Mitochondria in the Cystic Fibrosis Bronchial Epithelium. Cells 2022; 11:1938. [PMID: 35741067 PMCID: PMC9222197 DOI: 10.3390/cells11121938] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 06/07/2022] [Accepted: 06/12/2022] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Cystic Fibrosis (CF) is a genetic disorder affecting around 1 in every 3000 newborns. In the most common mutation, F508del, the defective anion channel, CFTR, is prevented from reaching the plasma membrane (PM) by the quality check control of the cell. Little is known about how CFTR pharmacological rescue impacts the cell proteome. METHODS We used high-resolution mass spectrometry, differential ultracentrifugation, machine learning and bioinformatics to investigate both changes in the expression and localization of the human bronchial epithelium CF model (F508del-CFTR CFBE41o-) proteome following treatment with VX-809 (Lumacaftor), a drug able to improve the trafficking of CFTR. RESULTS The data suggested no stark changes in protein expression, yet subtle localization changes of proteins of the mitochondria and peroxisomes were detected. We then used high-content confocal microscopy to further investigate the morphological and compositional changes of peroxisomes and mitochondria under these conditions, as well as in patient-derived primary cells. We profiled several thousand proteins and we determined the subcellular localization data for around 5000 of them using the LOPIT-DC spatial proteomics protocol. CONCLUSIONS We observed that treatment with VX-809 induces extensive structural and functional remodelling of mitochondria and peroxisomes that resemble the phenotype of healthy cells. Our data suggest additional rescue mechanisms of VX-809 beyond the correction of aberrant folding of F508del-CFTR and subsequent trafficking to the PM.
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Affiliation(s)
- Clarissa Braccia
- D3 PharmaChemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy; (C.B.); (T.B.)
| | - Josie A. Christopher
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK; (J.A.C.); (O.M.C.); (L.M.B.); (R.M.L.Q.)
| | - Oliver M. Crook
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK; (J.A.C.); (O.M.C.); (L.M.B.); (R.M.L.Q.)
- Department of Statistics, University of Oxford, 29 St Giles’, Oxford OX1 3LB, UK
| | - Lisa M. Breckels
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK; (J.A.C.); (O.M.C.); (L.M.B.); (R.M.L.Q.)
| | - Rayner M. L. Queiroz
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK; (J.A.C.); (O.M.C.); (L.M.B.); (R.M.L.Q.)
| | - Nara Liessi
- Analytical Chemistry Facility, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy;
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147 Genova, Italy; (V.T.); (V.C.); (S.B.)
| | - Valeria Capurro
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147 Genova, Italy; (V.T.); (V.C.); (S.B.)
| | - Tiziano Bandiera
- D3 PharmaChemistry, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy; (C.B.); (T.B.)
| | - Simona Baldassari
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147 Genova, Italy; (V.T.); (V.C.); (S.B.)
| | - Nicoletta Pedemonte
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147 Genova, Italy; (V.T.); (V.C.); (S.B.)
| | - Kathryn S. Lilley
- Cambridge Centre for Proteomics, Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QR, UK; (J.A.C.); (O.M.C.); (L.M.B.); (R.M.L.Q.)
| | - Andrea Armirotti
- Analytical Chemistry Facility, Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy;
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Theratyping of the Rare CFTR Variants E193K and R334W in Rectal Organoid-Derived Epithelial Monolayers. J Pers Med 2022; 12:jpm12040632. [PMID: 35455747 PMCID: PMC9027586 DOI: 10.3390/jpm12040632] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/29/2022] [Accepted: 04/01/2022] [Indexed: 12/17/2022] Open
Abstract
Background: The effect of presently available CFTR modulator combinations, such as elexacaftor (ELX), tezacaftor (TEZ), and ivacaftor (IVA), on rare CFTR alleles is often unknown. Several assays have been developed, such as forskolin-induced swelling (FIS), to evaluate the rescue of such uncommon CFTR alleles both by established and novel modulators in patient-derived primary cell cultures (organoids). Presently, we assessed the CFTR-mediated electrical current across rectal organoid-derived epithelial monolayers. This technique, which allows separate measurement of CFTR-dependent chloride or bicarbonate transport, was used to assess the effect of ELX/TEZ/IVA on two rare CFTR variants. Methods: Intestinal organoid cultures were established from rectal biopsies of CF patients carrying the rare missense mutations E193K or R334W paired with F508del. The effect of the CFTR modulator combination ELX/TEZ/IVA on CFTR-mediated Cl− and HCO3− secretion was assessed in organoid-derived intestinal epithelial monolayers. Non-CF organoids were used for comparison. Clinical biomarkers (sweat chloride, FEV1) were monitored in patients receiving modulator therapy. Results: ELX/TEZ/IVA markedly enhanced CFTR-mediated bicarbonate and chloride transport across intestinal epithelium of both patients. Consistent with the rescue of CFTR function in cultured intestinal cells, ELX/TEZ/IVA therapy improved biomarkers of CFTR function in the R334W/F508del patient. Conclusions: Current measurements in organoid-derived intestinal monolayers can readily be used to monitor CFTR-dependent epithelial Cl− and HCO3− transport. This technique can be explored to assess the functional consequences of rare CFTR mutations and the efficacy of CFTR modulators. We propose that this functional CFTR assay may guide personalized medicine in patients with CF-like clinical manifestations as well as in those carrying rare CFTR mutations.
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Seisel Q, Lakumpa I, Josse E, Vivès E, Varilh J, Taulan-Cadars M, Boisguérin P. Highway to Cell: Selection of the Best Cell-Penetrating Peptide to Internalize the CFTR-Stabilizing iCAL36 Peptide. Pharmaceutics 2022; 14:pharmaceutics14040808. [PMID: 35456644 PMCID: PMC9032934 DOI: 10.3390/pharmaceutics14040808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/28/2022] [Accepted: 03/31/2022] [Indexed: 11/23/2022] Open
Abstract
Therapeutic peptides have regained interest as they can address unmet medical needs and can be an excellent complement to pharmaceutic small molecules and other macromolecular therapeutics. Over the past decades, correctors and potentiators of the cystic fibrosis transmembrane conductance regulator (CFTR), a chloride ion channel causing cystic fibrosis (CF) when mutated, were developed to reduce the symptoms of the patients. In this context, we have previously designed a CFTR-stabilizing iCAL36 peptide able to further increase the CFTR amount in epithelial cells, thereby resulting in a higher CFTR activity. In the present study, optimization of the peptidyl inhibitor was performed by coupling five different cell-penetrating peptides (CPP), which are Tat, dTat, TatRI (retro-inverso), MPG, and Penetratin. Screening of the internalization properties of these CPP-iCAL36 peptides under different conditions (with or without serum or endocytosis inhibitors, etc.) was performed to select TatRI as the optimal CPP for iCAL36 delivery. More importantly, using this TatRI-iCAL36 peptide, we were able to reveal for the first time an additive increase in the CFTR amount in the presence of VX-445/VX-809 compared to VX-445/VX-809 treatment alone. This finding is a significant contribution to the development of CFTR-stabilizing peptides in addition to currently used treatments (small-molecule correctors or potentiators) for CF patients.
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Affiliation(s)
- Quentin Seisel
- CRBM, University of Montpellier, CNRS UMR 5237, 34000 Montpellier, France
| | - Israpong Lakumpa
- CRBM, University of Montpellier, CNRS UMR 5237, 34000 Montpellier, France
| | - Emilie Josse
- PhyMedExp, Bâtiment Crastes de Paulet, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
| | - Eric Vivès
- PhyMedExp, Bâtiment Crastes de Paulet, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
| | - Jessica Varilh
- PhyMedExp, Institut Universitaire de Recherche Clinique, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
| | - Magali Taulan-Cadars
- PhyMedExp, Institut Universitaire de Recherche Clinique, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
| | - Prisca Boisguérin
- PhyMedExp, Bâtiment Crastes de Paulet, University of Montpellier, INSERM U1046, CNRS UMR 9214, 34000 Montpellier, France
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Brusa I, Sondo E, Falchi F, Pedemonte N, Roberti M, Cavalli A. Proteostasis Regulators in Cystic Fibrosis: Current Development and Future Perspectives. J Med Chem 2022; 65:5212-5243. [PMID: 35377645 PMCID: PMC9014417 DOI: 10.1021/acs.jmedchem.1c01897] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In cystic fibrosis (CF), the deletion of phenylalanine 508 (F508del) in the CF transmembrane conductance regulator (CFTR) leads to misfolding and premature degradation of the mutant protein. These defects can be targeted with pharmacological agents named potentiators and correctors. During the past years, several efforts have been devoted to develop and approve new effective molecules. However, their clinical use remains limited, as they fail to fully restore F508del-CFTR biological function. Indeed, the search for CFTR correctors with different and additive mechanisms has recently increased. Among them, drugs that modulate the CFTR proteostasis environment are particularly attractive to enhance therapy effectiveness further. This Perspective focuses on reviewing the recent progress in discovering CFTR proteostasis regulators, mainly describing the design, chemical structure, and structure-activity relationships. The opportunities, challenges, and future directions in this emerging and promising field of research are discussed, as well.
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Affiliation(s)
- Irene Brusa
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy.,Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
| | - Elvira Sondo
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genova, Italy
| | | | | | - Marinella Roberti
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy
| | - Andrea Cavalli
- Department of Pharmacy and Biotechnology, University of Bologna, 40126 Bologna, Italy.,Computational & Chemical Biology, Istituto Italiano di Tecnologia, 16163 Genova, Italy
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Principi E, Sondo E, Bianchi G, Ravera S, Morini M, Tomati V, Pastorino C, Zara F, Bruno C, Eva A, Pedemonte N, Raffaghello L. Targeting of Ubiquitin E3 Ligase RNF5 as a Novel Therapeutic Strategy in Neuroectodermal Tumors. Cancers (Basel) 2022; 14:cancers14071802. [PMID: 35406574 PMCID: PMC8997491 DOI: 10.3390/cancers14071802] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 01/27/2023] Open
Abstract
RNF5, an endoplasmic reticulum (ER) E3 ubiquitin ligase, participates to the ER-associated protein degradation guaranteeing the protein homeostasis. Depending on tumor model tested, RNF5 exerts pro- or anti-tumor activity. The aim of this study was to elucidate the controversial role of RNF5 in neuroblastoma and melanoma, two neuroectodermal tumors of infancy and adulthood, respectively. RNF5 gene levels are evaluated in publicly available datasets reporting the gene expression profile of melanoma and neuroblastoma primary tumors at diagnosis. The therapeutic effect of Analog-1, an RNF5 pharmacological activator, was investigated on in vitro and in vivo neuroblastoma and melanoma models. In both neuroblastoma and melanoma patients the high expression of RNF5 correlated with a better prognostic outcome. Treatment of neuroblastoma and melanoma cell lines with Analog-1 reduced cell viability by impairing the glutamine availability and energy metabolism through inhibition of F1Fo ATP-synthase activity. This latter event led to a marked increase in oxidative stress, which, in turn, caused cell death. Similarly, neuroblastoma- and melanoma-bearing mice treated with Analog-1 showed a significant delay of tumor growth in comparison to those treated with vehicle only. These findings validate RNF5 as an innovative drug target and support the development of Analog-1 in early phase clinical trials for neuroblastoma and melanoma patients.
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Affiliation(s)
- Elisa Principi
- Center of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Elvira Sondo
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Giovanna Bianchi
- Stem Cell Laboratory and Cell Therapy Center, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Silvia Ravera
- Experimental Medicine Department, University of Genova, 16132 Genova, Italy
| | - Martina Morini
- Laboratory of Molecular Biology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | - Cristina Pastorino
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DI-NOGMI), University of Genoa, 16132 Genoa, Italy
| | - Federico Zara
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DI-NOGMI), University of Genoa, 16132 Genoa, Italy
| | - Claudio Bruno
- Center of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
- Department of Neurosciences, Rehabilitation, Ophthalmology, Genetics, Maternal and Child Health (DI-NOGMI), University of Genoa, 16132 Genoa, Italy
| | - Alessandra Eva
- Laboratory of Molecular Biology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
| | | | - Lizzia Raffaghello
- Center of Translational and Experimental Myology, IRCCS Istituto Giannina Gaslini, 16147 Genoa, Italy
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Borgo C, D'Amore C, Capurro V, Tomati V, Sondo E, Cresta F, Castellani C, Pedemonte N, Salvi M. Targeting the E1 ubiquitin-activating enzyme (UBA1) improves elexacaftor/tezacaftor/ivacaftor efficacy towards F508del and rare misfolded CFTR mutants. Cell Mol Life Sci 2022; 79:192. [PMID: 35292885 PMCID: PMC8924136 DOI: 10.1007/s00018-022-04215-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Revised: 02/16/2022] [Accepted: 02/21/2022] [Indexed: 02/08/2023]
Abstract
The advent of Trikafta (Kaftrio in Europe) (a triple-combination therapy based on two correctors—elexacaftor/tezacaftor—and the potentiator ivacaftor) has represented a revolution for the treatment of patients with cystic fibrosis (CF) carrying the most common misfolding mutation, F508del-CFTR. This therapy has proved to be of great efficacy in people homozygous for F508del-CFTR and is also useful in individuals with a single F508del allele. Nevertheless, the efficacy of this therapy needs to be improved, especially in light of the extent of its use in patients with rare class II CFTR mutations. Using CFBE41o- cells expressing F508del-CFTR, we provide mechanistic evidence that targeting the E1 ubiquitin-activating enzyme (UBA1) by TAK-243, a small molecule in clinical trials for other diseases, boosts the rescue of F508del-CFTR induced by CFTR correctors. Moreover, TAK-243 significantly increases the F508del-CFTR short-circuit current induced by elexacaftor/tezacaftor/ivacaftor in differentiated human primary airway epithelial cells, a gold standard for the pre-clinical evaluation of patients’ responsiveness to pharmacological treatments. This new combinatory approach also leads to an improvement in CFTR conductance on cells expressing other rare CF-causing mutations, including N1303K, for which Trikafta is not approved. These findings show that Trikafta therapy can be improved by the addition of a drug targeting the misfolding detection machinery at the beginning of the ubiquitination cascade and may pave the way for an extension of Trikafta to low/non-responding rare misfolded CFTR mutants.
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Affiliation(s)
- Christian Borgo
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy.
| | - Claudio D'Amore
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy
| | - Valeria Capurro
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genova, Italy
| | - Valeria Tomati
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genova, Italy
| | - Elvira Sondo
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genova, Italy
| | - Federico Cresta
- Centro Fibrosi Cistica, IRCCS Istituto Giannina Gaslini, Genova, Italy
| | - Carlo Castellani
- Centro Fibrosi Cistica, IRCCS Istituto Giannina Gaslini, Genova, Italy
| | - Nicoletta Pedemonte
- UOC Genetica Medica, IRCCS Istituto Giannina Gaslini, Via Gerolamo Gaslini 5, 16147, Genova, Italy.
| | - Mauro Salvi
- Department of Biomedical Sciences, University of Padova, Via Ugo Bassi 58/B, 35131, Padova, Italy.
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37
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The L467F-F508del Complex Allele Hampers Pharmacological Rescue of Mutant CFTR by Elexacaftor/Tezacaftor/Ivacaftor in Cystic Fibrosis Patients: The Value of the Ex Vivo Nasal Epithelial Model to Address Non-Responders to CFTR-Modulating Drugs. Int J Mol Sci 2022; 23:ijms23063175. [PMID: 35328596 PMCID: PMC8952007 DOI: 10.3390/ijms23063175] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2022] [Revised: 03/10/2022] [Accepted: 03/14/2022] [Indexed: 12/16/2022] Open
Abstract
Loss-of-function mutations of the CFTR gene cause cystic fibrosis (CF) through a variety of molecular mechanisms involving altered expression, trafficking, and/or activity of the CFTR chloride channel. The most frequent mutation among CF patients, F508del, causes multiple defects that can be, however, overcome by a combination of three pharmacological agents that improve CFTR channel trafficking and gating, namely, elexacaftor, tezacaftor, and ivacaftor. This study was prompted by the evidence of two CF patients, compound heterozygous for F508del and a minimal function variant, who failed to obtain any beneficial effects following treatment with the triple drug combination. Functional studies on nasal epithelia generated in vitro from these patients confirmed the lack of response to pharmacological treatment. Molecular characterization highlighted the presence of an additional amino acid substitution, L467F, in cis with the F508del variant, demonstrating that both patients were carriers of a complex allele. Functional and biochemical assays in heterologous expression systems demonstrated that the double mutant L467F-F508del has a severely reduced activity, with negligible rescue by CFTR modulators. While further studies are needed to investigate the actual prevalence of the L467F-F508del allele, our results suggest that this complex allele should be taken into consideration as plausible cause in CF patients not responding to CFTR modulators.
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Taniguchi S, Ito Y, Kiritani H, Maruo A, Sakai R, Ono Y, Fukuda R, Okiyoneda T. The Ubiquitin Ligase RNF34 Participates in the Peripheral Quality Control of CFTR (RNF34 Role in CFTR PeriQC). Front Mol Biosci 2022; 9:840649. [PMID: 35355508 PMCID: PMC8959631 DOI: 10.3389/fmolb.2022.840649] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 01/18/2022] [Indexed: 11/27/2022] Open
Abstract
The peripheral protein quality control (periQC) system eliminates the conformationally defective cystic fibrosis transmembrane conductance regulator (CFTR), including ∆F508-CFTR, from the plasma membrane (PM) and limits the efficacy of pharmacological therapy for cystic fibrosis (CF). The ubiquitin (Ub) ligase RFFL is responsible for the chaperone-independent ubiquitination and lysosomal degradation of CFTR in the periQC. Here, we report that the Ub ligase RNF34 participates in the CFTR periQC in parallel to RFFL. An in vitro study reveals that RNF34 directly recognizes the CFTR NBD1 and selectively promotes the ubiquitination of unfolded proteins. RNF34 was localized in the cytoplasm and endosomes, where RFFL was equally colocalized. RNF34 ablation increased the PM density as well as the mature form of ∆F508-CFTR rescued at low temperatures. RFFL ablation, with the exception of RNF34 ablation, increased the functional PM expression of ∆F508-CFTR upon a triple combination of CFTR modulators (Trikafta) treatment by inhibiting the K63-linked polyubiquitination. Interestingly, simultaneous ablation of RNF34 and RFFL dramatically increased the functional PM ∆F508-CFTR by inhibiting the ubiquitination in the post-Golgi compartments. The CFTR-NLuc assay demonstrates that simultaneous ablation of RNF34 and RFFL dramatically inhibits the degradation of mature ∆F508-CFTR after Trikafta treatment. Therefore, these results suggest that RNF34 plays a crucial role in the CFTR periQC, especially when there is insufficient RFFL. We propose that simultaneous inhibition of RFFL and RNF34 may improve the efficacy of CFTR modulators.
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Rescue of Mutant CFTR Trafficking Defect by the Investigational Compound MCG1516A. Cells 2022; 11:cells11010136. [PMID: 35011698 PMCID: PMC8750248 DOI: 10.3390/cells11010136] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 12/20/2021] [Accepted: 12/22/2021] [Indexed: 01/27/2023] Open
Abstract
Although some therapeutic progress has been achieved in developing small molecules that correct F508del-CFTR defects, the mechanism of action (MoA) of these compounds remain poorly elucidated. Here, we investigated the effects and MoA of MCG1516A, a newly developed F508del-CFTR corrector. MCG1516A effects on wild-type (WT) and F508del-CFTR were assessed by immunofluorescence microscopy, and biochemical and functional assays both in cell lines and in intestinal organoids. To shed light on the MoA of MCG1516A, we evaluated its additivity to the FDA-approved corrector VX-661, low temperature, genetic revertants of F508del-CFTR (G550E, R1070W, and 4RK), and the traffic-null variant DD/AA. Finally, we explored the ability of MCG1516A to rescue trafficking and function of other CF-causing mutations. We found that MCG1516A rescues F508del-CFTR with additive effects to VX-661. A similar behavior was observed for WT-CFTR. Under low temperature incubation, F508del-CFTR demonstrated an additivity in processing and function with VX-661, but not with MCG1516A. In contrast, both compounds promoted additional effects to low temperature to WT-CFTR. MCG1516A demonstrated additivity to genetic revertant R1070W, while VX-661 was additive to G550E and 4RK. Nevertheless, none of these compounds rescued DD/AA trafficking. Both MCG1516A and VX-661 rescued CFTR processing of L206W- and R334W-CFTR with greater effects when these compounds were combined. In summary, the absence of additivity of MCG1516A to genetic revertant G550E suggests a putative binding site for this compound on NBD1:NBD2 interface. Therefore, a combination of MCG1516A with compounds able to rescue DD/AA traffic, or mimicking the actions of revertant R1070W (e.g., VX-661), could enhance correction of F508del-CFTR defects.
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Angyal D, Bijvelds MJC, Bruno MJ, Peppelenbosch MP, de Jonge HR. Bicarbonate Transport in Cystic Fibrosis and Pancreatitis. Cells 2021; 11:cells11010054. [PMID: 35011616 PMCID: PMC8750324 DOI: 10.3390/cells11010054] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 12/20/2021] [Accepted: 12/21/2021] [Indexed: 12/12/2022] Open
Abstract
CFTR, the cystic fibrosis (CF) gene-encoded epithelial anion channel, has a prominent role in driving chloride, bicarbonate and fluid secretion in the ductal cells of the exocrine pancreas. Whereas severe mutations in CFTR cause fibrosis of the pancreas in utero, CFTR mutants with residual function, or CFTR variants with a normal chloride but defective bicarbonate permeability (CFTRBD), are associated with an enhanced risk of pancreatitis. Recent studies indicate that CFTR function is not only compromised in genetic but also in selected patients with an acquired form of pancreatitis induced by alcohol, bile salts or smoking. In this review, we summarize recent insights into the mechanism and regulation of CFTR-mediated and modulated bicarbonate secretion in the pancreatic duct, including the role of the osmotic stress/chloride sensor WNK1 and the scaffolding protein IRBIT, and current knowledge about the role of CFTR in genetic and acquired forms of pancreatitis. Furthermore, we discuss the perspectives for CFTR modulator therapy in the treatment of exocrine pancreatic insufficiency and pancreatitis and introduce pancreatic organoids as a promising model system to study CFTR function in the human pancreas, its role in the pathology of pancreatitis and its sensitivity to CFTR modulators on a personalized basis.
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Graeber SY, Vitzthum C, Pallenberg ST, Naehrlich L, Stahl M, Rohrbach A, Drescher M, Minso R, Ringshausen FC, Rueckes-Nilges C, Klajda J, Berges J, Yu Y, Scheuermann H, Hirtz S, Sommerburg O, Dittrich AM, Tümmler B, Mall MA. Effects of Elexacaftor/Tezacaftor/Ivacaftor Therapy on CFTR Function in Patients with Cystic Fibrosis and One or Two F508del Alleles. Am J Respir Crit Care Med 2021; 205:540-549. [PMID: 34936849 DOI: 10.1164/rccm.202110-2249oc] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
RATIONALE The CFTR modulator combination elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) was shown to improve clinical outcomes and sweat chloride concentration (SCC) in patients with cystic fibrosis (CF) and one or two F508del alleles. However, the effect of ELX/TEZ/IVA on CFTR function in the airways and intestine has not been studied. OBJECTIVES To assess the effect of ELX/TEZ/IVA on CFTR function in airway and intestinal epithelia in patients with CF and one or two F508del alleles aged 12 years and older. METHODS This prospective observational multicenter study assessed clinical outcomes including FEV1 %predicted and body mass index, and the CFTR biomarkers SCC, nasal potential difference (NPD) and intestinal current measurement (ICM) before and 8-16 weeks after initiation of ELX/TEZ/IVA. MEASUREMENTS AND MAIN RESULTS A total of 107 patients with CF including 55 patients with one F508del and a minimal function mutation and 52 F508del homozygous patients were enrolled in this study. In patients with one F508del allele, NPD and ICM showed that ELX/TEZ/IVA improved CFTR function in nasal epithelia to a level of 46.5% (IQR, 27.5-72.4; P<0.001) and in intestinal epithelia to 41.8% of normal (IQR, 25.1-57.6; P<0.001). In F508del homozygous patients, ELX/TEZ/IVA exceeded improvement of CFTR function observed with TEZ/IVA and increased CFTR-mediated Cl- secretion to a level of 47.4% of normal (IQR, 19.3-69.2; P<0.001) in nasal and to 45.9% (IQR, 19.7-66.6; P<0.001) in intestinal epithelia. CONCLUSIONS Treatment with ELX/TEZ/IVA results in effective improvement of CFTR function in airway and intestinal epithelia in patients with CF and one or two F508del alleles.
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Affiliation(s)
- Simon Y Graeber
- Charité Universitätsmedizin Berlin, 14903, Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Berlin, Germany.,Berlin Institute of Health, 522475, Berlin, Germany.,German Center for Lung Research, 542891, associated partner, Berlin, Germany
| | - Constanze Vitzthum
- Charité Universitätsmedizin Berlin, 14903, Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Berlin, Germany.,German Center for Lung Research, 542891, associated partner, Berlin, Germany
| | - Sophia T Pallenberg
- Hannover Medical School, 9177, Department of Pediatric Pneumology, Allergology and Neonatology, Hannover, Germany.,German Center for Lung Research, 542891, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Hannover, Germany
| | - Lutz Naehrlich
- Justus-Liebig-University Giessen, Department of Pediatrics, Giessen, Germany.,German Center for Lung Research, 542891, Universities of Giessen and Marburg Lung Center (UGMLC), Giessen, Germany
| | - Mirjam Stahl
- Charité Universitätsmedizin Berlin, 14903, Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Berlin, Germany.,Berlin Institute of Health, 522475, Berlin, Germany.,German Center for Lung Research, 542891, associated partner, Berlin, Germany
| | - Alexander Rohrbach
- Charité Universitätsmedizin Berlin, 14903, Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Berlin, Germany
| | - Marika Drescher
- Charité Universitätsmedizin Berlin, 14903, Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Berlin, Germany.,German Center for Lung Research, 542891, associated partner, Berlin, Germany
| | - Rebecca Minso
- Hannover Medical School, 9177, Department of Pediatric Pneumology, Allergology and Neonatology, Hannover, Germany
| | - Felix C Ringshausen
- Hannover Medical School, 9177, Department of Respiratory Medicine, Hannover, Germany.,German Center for Lung Research, 542891, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Hannover, Germany
| | | | - Jan Klajda
- Justus-Liebig-University Giessen, Department of Pediatrics, Giessen, Germany
| | - Julian Berges
- University of Heidelberg, 9144, Department of Pediatrics, Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Heidelberg, Germany.,University of Heidelberg, 9144, Department of Translational Pulmonology, Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
| | - Yin Yu
- University of Heidelberg, 9144, Department of Pediatrics, Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Heidelberg, Germany.,University of Heidelberg, 9144, German Centre for Lung Research (DZL), Translational Lung Research Center Heidelberg (TLRC), Department of Translational Pulmonology, Heidelberg, Germany
| | - Heike Scheuermann
- University of Heidelberg, 9144, Department of Pediatrics, Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Heidelberg, Germany.,University of Heidelberg, 9144, Department of Translational Pulmonology, Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
| | - Stephanie Hirtz
- University of Heidelberg, 9144, Department of Pediatrics, Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Heidelberg, Germany.,University of Heidelberg, 9144, Department of Translational Pulmonology, Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
| | - Olaf Sommerburg
- University of Heidelberg, 9144, Department of Pediatrics, Division of Pediatric Pulmonology and Allergy and Cystic Fibrosis Center, Heidelberg, Germany.,University of Heidelberg, 9144, Department of Translational Pulmonology, Translational Lung Research Center Heidelberg (TLRC), German Center for Lung Research (DZL), Heidelberg, Germany
| | - Anna-Maria Dittrich
- Hannover Medical School, 9177, Department of Pediatric Pneumology, Allergology and Neonatology, Hannover, Germany.,German Center for Lung Research, 542891, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Hannover, Germany
| | - Burkhard Tümmler
- Hannover Medical School, 9177, Department of Pediatric Pneumology, Allergology and Neonatology, Hannover, Germany.,German Center for Lung Research, 542891, Biomedical Research in Endstage and Obstructive Lung Disease Hannover (BREATH), Hannover, Germany
| | - Marcus A Mall
- Charité Universitätsmedizin Berlin, 14903, Department of Pediatric Respiratory Medicine, Immunology and Critical Care Medicine and Cystic Fibrosis Center, Berlin, Germany.,Berlin Institute of Health, 522475, Berlin, Germany.,German Center for Lung Research, 542891, associated partner, Berlin, Germany;
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Hryciw DH, Jackson CA, Shrestha N, Parsons D, Donnelley M, McAinch AJ. Role for animal models in understanding essential fatty acid deficiency in cystic fibrosis. Cell Mol Life Sci 2021; 78:7991-7999. [PMID: 34741185 PMCID: PMC11072998 DOI: 10.1007/s00018-021-04014-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Revised: 10/11/2021] [Accepted: 10/25/2021] [Indexed: 10/19/2022]
Abstract
Essential fatty acid deficiency has been observed in most patients with Cystic Fibrosis (CF); however, pancreatic supplementation does not restore the deficiency, suggesting a different pathology independent of the pancreas. At this time, the underlying pathological mechanisms are largely unknown. Essential fatty acids are obtained from the diet and processed by organs including the liver and intestine, two organs significantly impacted by mutations in the cystic fibrosis transmembrane conductance regulator gene (Cftr). There are several CF animal models in a variety of species that have been developed to investigate molecular mechanisms associated with the CF phenotype. Specifically, global and systemic mutations in Cftr which mimic genotypic changes identified in CF patients have been generated in mice, rats, sheep, pigs and ferrets. These mutations produce CFTR proteins with a gating defect, trafficking defect, or an absent or inactive CFTR channel. Essential fatty acids are critical to CFTR function, with a bidirectional relationship between CFTR and essential fatty acids proposed. Currently, there are limited analyses on the essential fatty acid status in most of these animal models. Of interest, in the mouse model, essential fatty acid status is dependent on the genotype and resultant phenotype of the mouse. Future investigations should identify an optimal animal model that has most of the phenotypic changes associated with CF including the essential fatty acid deficiencies, which can be used in the development of therapeutics.
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Affiliation(s)
- Deanne H Hryciw
- School of Environment and Science, Griffith University, Nathan, QLD, Australia.
- Centre for Planetary Health and Food Security, Griffith University, Nathan, QLD, Australia.
- Institute for Health and Sport, Victoria University, Melbourne, VIC, Australia.
| | - Courtney A Jackson
- School of Environment and Science, Griffith University, Nathan, QLD, Australia
| | - Nirajan Shrestha
- School of Pharmacy and Medical Sciences, Griffith University, Southport, QLD, Australia
| | - David Parsons
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- Respiratory and Sleep Medicine, Women's and Children's Hospital, North Adelaide, SA, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Martin Donnelley
- Adelaide Medical School, University of Adelaide, Adelaide, SA, Australia
- Respiratory and Sleep Medicine, Women's and Children's Hospital, North Adelaide, SA, Australia
- Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
| | - Andrew J McAinch
- Institute for Health and Sport, Victoria University, Melbourne, VIC, Australia
- Australian Institute for Musculoskeletal Science (AIMSS), Victoria University, St. Albans, VIC, Australia
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Comprehensive Analysis of Combinatorial Pharmacological Treatments to Correct Nonsense Mutations in the CFTR Gene. Int J Mol Sci 2021; 22:ijms222111972. [PMID: 34769402 PMCID: PMC8584557 DOI: 10.3390/ijms222111972] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 10/29/2021] [Accepted: 11/02/2021] [Indexed: 12/11/2022] Open
Abstract
Cystic fibrosis (CF) is caused by loss of function of the CFTR chloride channel. A substantial number of CF patients carry nonsense mutations in the CFTR gene. These patients cannot directly benefit from pharmacological correctors and potentiators that have been developed for other types of CFTR mutations. We evaluated the efficacy of combinations of drugs targeting at various levels the effects of nonsense mutations: SMG1i to protect CFTR mRNA from nonsense-mediated decay (NMD), G418 and ELX-02 for readthrough, VX-809 and VX-445 to promote protein maturation and function, PTI-428 to enhance CFTR protein synthesis. We found that the extent of rescue and sensitivity to the various agents is largely dependent on the type of mutation, with W1282X and R553X being the mutations most and least sensitive to pharmacological treatments, respectively. In particular, W1282X-CFTR was highly responsive to NMD suppression by SMG1i but also required treatment with VX-445 corrector to show function. In contrast, G542X-CFTR required treatment with readthrough agents and VX-809. Importantly, we never found cooperativity between the NMD inhibitor and readthrough compounds. Our results indicate that treatment of CF patients with nonsense mutations requires a precision medicine approach with the design of specific drug combinations for each mutation.
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Pinto MC, Silva IAL, Figueira MF, Amaral MD, Lopes-Pacheco M. Pharmacological Modulation of Ion Channels for the Treatment of Cystic Fibrosis. J Exp Pharmacol 2021; 13:693-723. [PMID: 34326672 PMCID: PMC8316759 DOI: 10.2147/jep.s255377] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 06/30/2021] [Indexed: 12/12/2022] Open
Abstract
Cystic fibrosis (CF) is a life-shortening monogenic disease caused by mutations in the gene encoding the CF transmembrane conductance regulator (CFTR) protein, an anion channel that transports chloride and bicarbonate across epithelia. Despite clinical progress in delaying disease progression with symptomatic therapies, these individuals still develop various chronic complications in lungs and other organs, which significantly restricts their life expectancy and quality of life. The development of high-throughput assays to screen drug-like compound libraries have enabled the discovery of highly effective CFTR modulator therapies. These novel therapies target the primary defect underlying CF and are now approved for clinical use for individuals with specific CF genotypes. However, the clinically approved modulators only partially reverse CFTR dysfunction and there is still a considerable number of individuals with CF carrying rare CFTR mutations who remain without any effective CFTR modulator therapy. Accordingly, additional efforts have been pursued to identify novel and more potent CFTR modulators that may benefit a larger CF population. The use of ex vivo individual-derived specimens has also become a powerful tool to evaluate novel drugs and predict their effectiveness in a personalized medicine approach. In addition to CFTR modulators, pro-drugs aiming at modulating alternative ion channels/transporters are under development to compensate for the lack of CFTR function. These therapies may restore normal mucociliary clearance through a mutation-agnostic approach (ie, independent of CFTR mutation) and include inhibitors of the epithelial sodium channel (ENaC), modulators of the calcium-activated channel transmembrane 16A (TMEM16, or anoctamin 1) or of the solute carrier family 26A member 9 (SLC26A9), and anionophores. The present review focuses on recent progress and challenges for the development of ion channel/transporter-modulating drugs for the treatment of CF.
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Affiliation(s)
- Madalena C Pinto
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Iris A L Silva
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Miriam F Figueira
- Marsico Lung Institute/Cystic Fibrosis Center, University of North Carolina at Chapel Hill, Chapel Hill, NC, USA
| | - Margarida D Amaral
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
| | - Miquéias Lopes-Pacheco
- Biosystems & Integrative Sciences Institute (BioISI), Faculty of Sciences, University of Lisboa, Lisboa, Portugal
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Becq F, Mirval S, Carrez T, Lévêque M, Billet A, Coraux C, Sage E, Cantereau A. The rescue of F508del-CFTR by elexacaftor/tezacaftor/ivacaftor (Trikafta) in human airway epithelial cells is underestimated due to the presence of ivacaftor. Eur Respir J 2021; 59:13993003.00671-2021. [PMID: 34266939 DOI: 10.1183/13993003.00671-2021] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 06/25/2021] [Indexed: 11/05/2022]
Abstract
Trikafta, currently the leading therapeutic in Cystic Fibrosis (CF), has demonstrated a real clinical benefit. This treatment is the triple combination therapy of two folding correctors elexacaftor/tezacaftor (VX445/VX661) plus the gating potentiator ivacaftor (VX770). In this study, our aim was to compare the properties of F508del-CFTR in cells treated with either lumacaftor (VX809), tezacaftor, elexacaftor, elexacaftor/tezacaftor with or without ivacaftor. We studied F508del-CFTR function, maturation and membrane localisation by Ussing chamber and whole-cell patch clamp recordings, Western blot and immunolocalization experiments. With human primary airway epithelial cells and the cell lines CFBE and BHK expressing F508del, we found that, whereas the combination elexacaftor/tezacaftor/ivacaftor was efficient in rescuing F508del-CFTR abnormal maturation, apical membrane location and function, the presence of ivacaftor limits these effects. The basal F508del-CFTR short-circuit current was significantly increased by elexacaftor/tezacaftor/ivacaftor and elexacaftor/tezacaftor compared to other correctors and non-treated cells, an effect dependent on ivacaftor and cAMP. These results suggest that the level of the basal F508del-CFTR current might be a marker for correction efficacy in CF cells. When cells were treated with ivacaftor combined to any correctors, the F508del-CFTR current was unresponsive to the subsequently acute addition of ivacaftor unlike the CFTR potentiators genistein and Cact-A1 which increased elexacaftor/tezacaftor/ivacaftor and elexacaftor/tezacaftor-corrected F508del-CFTR currents. These findings show that ivacaftor reduces the correction efficacy of Trikafta. Thus, combining elexacaftor/tezacaftor with a different potentiator might improve the therapeutic efficacy for treating CF patients.
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Affiliation(s)
- Frédéric Becq
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, France
| | - Sandra Mirval
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, France
| | - Thomas Carrez
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, France.,ManRos therapeutics, Presqu'île de Perharidy, Roscoff, France
| | - Manuella Lévêque
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, France
| | - Arnaud Billet
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, France
| | - Christelle Coraux
- INSERM UMR-S 1250, Université de Reims-Champagne Ardenne, Reims, France
| | - Edouard Sage
- INRAE UMR 0892, Université Versailles-Saint-Quentin-en-Yvelines, Versailles, France.,Service de chirurgie thoracique et transplantation pulmonaire, Hôpital Foch, Suresnes, France
| | - Anne Cantereau
- Laboratoire Signalisation et Transports Ioniques Membranaires, Université de Poitiers, France
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A Precision Medicine Approach to Optimize Modulator Therapy for Rare CFTR Folding Mutants. J Pers Med 2021; 11:jpm11070643. [PMID: 34357110 PMCID: PMC8307171 DOI: 10.3390/jpm11070643] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Revised: 06/30/2021] [Accepted: 07/05/2021] [Indexed: 12/23/2022] Open
Abstract
Trikafta, a triple-combination drug, consisting of folding correctors VX-661 (tezacaftor), VX-445 (elexacaftor) and the gating potentiator VX-770 (ivacaftor) provided unprecedented clinical benefits for patients with the most common cystic fibrosis (CF) mutation, F508del. Trikafta indications were recently expanded to additional 177 mutations in the CF transmembrane conductance regulator (CFTR). To minimize life-long pharmacological and financial burden of drug administration, if possible, we determined the necessary and sufficient modulator combination that can achieve maximal benefit in preclinical setting for selected mutants. To this end, the biochemical and functional rescue of single corrector-responsive rare mutants were investigated in a bronchial epithelial cell line and patient-derived human primary nasal epithelia (HNE), respectively. The plasma membrane density of P67L-, L206W- or S549R-CFTR corrected by VX-661 or other type I correctors was moderately increased by VX-445. Short-circuit current measurements of HNE, however, uncovered that correction comparable to Trikafta was achieved for S549R-CFTR by VX-661 + VX-770 and for P67L- and L206W-CFTR by the VX-661 + VX-445 combination. Thus, introduction of a third modulator may not provide additional benefit for patients with a subset of rare CFTR missense mutations. These results also underscore that HNE, as a precision medicine model, enable the optimization of mutation-specific modulator combinations to maximize their efficacy and minimize life-long drug exposure of CF patients.
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