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Shah D, Patel A. Eco-friendly approaches to 1,3,4-oxadiazole derivatives: A comprehensive review of green synthetic strategies. Arch Pharm (Weinheim) 2024:e2400185. [PMID: 38877614 DOI: 10.1002/ardp.202400185] [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: 03/12/2024] [Revised: 05/10/2024] [Accepted: 05/13/2024] [Indexed: 06/16/2024]
Abstract
This review article offers an environmentally benign synthesis of 1,3,4-oxadiazole derivatives, with a focus on sustainable methodologies that have minimal impact on the environment. These derivatives, known for their diverse applications, have conventionally been associated with synthesis methods that utilize hazardous reagents and produce significant waste, thereby raising environmental concerns. The green synthesis of 1,3,4-oxadiazole derivatives employs renewable substrates, nontoxic catalysts, and mild reaction conditions, aiming to minimize the environmental impact. Innovative techniques such as catalyst-based, catalyst-free, electrochemical synthesis, green-solvent-mediated synthesis, grinding, microwave-mediated synthesis, and photosynthesis are implemented, providing benefits in terms of scalability, cost-effectiveness, and ease of purification. This review emphasizes the significance of sustainable methodologies in the synthesis of 1,3,4-oxadiazole and boots for continued exploration in this research domain.
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Affiliation(s)
- Drashti Shah
- Department of Pharmaceutical Chemistry, Ramanbhai Patel College of Pharmacy, Charotar University of Science and Technology, Anand, Gujarat, India
- Department of Pharmaceutical Chemistry, L. J. Institute of Pharmacy, L J University, Ahmedabad, India
| | - Ashish Patel
- Department of Pharmaceutical Chemistry, Ramanbhai Patel College of Pharmacy, Charotar University of Science and Technology, Anand, Gujarat, India
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2
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Pan Y, Adachi H, He X, Chen JL, Yu YT, Boutz PL. Updated Pseudo-seq Protocol for Transcriptome-Wide Detection of Pseudouridines. Bio Protoc 2024; 14:e4985. [PMID: 38737508 PMCID: PMC11082786 DOI: 10.21769/bioprotoc.4985] [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: 01/15/2024] [Revised: 04/07/2024] [Accepted: 04/09/2024] [Indexed: 05/14/2024] Open
Abstract
Pseudouridine (Ψ), the most prevalent modified base in cellular RNAs, has been mapped to numerous sites not only in rRNAs, tRNAs, and snRNAs but also mRNAs. Although there have been multiple techniques to identify Ψs, due to the recent development of sequencing technologies some reagents are not compatible with the current sequencer. Here, we show the updated Pseudo-seq, a technique enabling the genome-wide identification of pseudouridylation sites with single-nucleotide precision. We provide a comprehensive description of Pseudo-seq, covering protocols for RNA isolation from human cells, library preparation, and detailed data analysis procedures. The methodology presented is easily adaptable to any cell or tissue type with high-quality mRNA isolation. It can be used for discovering novel pseudouridylation sites, thus constituting a crucial initial step toward understanding the regulation and function of this modification. Key features • Identification of Ψ sites on mRNAs. • Updated Pseudo-seq provides precise positional and quantitative information of Ψ. • Uses a more efficient library preparation with the latest, currently available materials.
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Affiliation(s)
- Yi Pan
- University of Rochester Medical Center, Department of Biochemistry and Biophysics, Center for RNA Biology, Rochester, NY, USA
| | - Hironori Adachi
- University of Rochester Medical Center, Department of Biochemistry and Biophysics, Center for RNA Biology, Rochester, NY, USA
| | - Xueyang He
- University of Rochester Medical Center, Department of Biochemistry and Biophysics, Center for RNA Biology, Rochester, NY, USA
| | - Jonathan L. Chen
- University of Rochester Medical Center, Department of Biochemistry and Biophysics, Center for RNA Biology, Rochester, NY, USA
| | - Yi-Tao Yu
- University of Rochester Medical Center, Department of Biochemistry and Biophysics, Center for RNA Biology, Rochester, NY, USA
| | - Paul L. Boutz
- University of Rochester Medical Center, Department of Biochemistry and Biophysics, Center for RNA Biology, Rochester, NY, USA
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3
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Pascoe JE, Zygmunt A, Ehsan Z, Gurbani N. Sleep in pediatric neuromuscular disorders. Semin Pediatr Neurol 2023; 48:101092. [PMID: 38065635 DOI: 10.1016/j.spen.2023.101092] [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: 08/14/2023] [Revised: 10/06/2023] [Accepted: 10/09/2023] [Indexed: 12/18/2023]
Abstract
Sleep disordered breathing (SDB) is prevalent among children with neuromuscular disorders (NMD). The combination of respiratory muscle weakness, altered drive, and chest wall distortion due to scoliosis make sleep a stressful state in this population. Symptomatology can range from absent to snoring, nocturnal awakenings, morning headaches, and excessive daytime sleepiness. Sequelae of untreated SDB includes cardiovascular effects, metabolic derangements, and neurocognitive concerns which can be compounded by those innate to the NMD. The clinician should have a low threshold for obtaining polysomnography and recognize the nuances of individual disorders due to disproportionately impacted muscle groups such as hypoventilation in ambulating patients from diaphragm weakness. Non-invasive or invasive ventilation are the mainstay of treatment. In this review we explore the diagnosis and treatment of SDB in children with various NMD.
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Affiliation(s)
- John E Pascoe
- Division of Pulmonary and Sleep Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States.
| | - Alexander Zygmunt
- Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States; Division of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States
| | - Zarmina Ehsan
- Division of Pulmonary and Sleep Medicine, Children's Mercy-Kansas City, Kansas City, MO, United States; Department of Pediatrics, University of Missouri-Kansas City School of Medicine, Kansas City, MO, United States
| | - Neepa Gurbani
- Division of Pulmonary and Sleep Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, United States; Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, United States
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4
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Mercuri E, Osorio AN, Muntoni F, Buccella F, Desguerre I, Kirschner J, Tulinius M, de Resende MBD, Morgenroth LP, Gordish-Dressman H, Johnson S, Kristensen A, Werner C, Trifillis P, Henricson EK, McDonald CM. Safety and effectiveness of ataluren in patients with nonsense mutation DMD in the STRIDE Registry compared with the CINRG Duchenne Natural History Study (2015-2022): 2022 interim analysis. J Neurol 2023:10.1007/s00415-023-11687-1. [PMID: 37115359 PMCID: PMC10141820 DOI: 10.1007/s00415-023-11687-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 03/24/2023] [Accepted: 03/26/2023] [Indexed: 04/29/2023]
Abstract
OBJECTIVE Strategic Targeting of Registries and International Database of Excellence (STRIDE) is an ongoing, international, multicenter registry of real-world ataluren use in individuals with nonsense mutation Duchenne muscular dystrophy (nmDMD) in clinical practice. This updated interim report (data cut-off: January 31, 2022), describes STRIDE patient characteristics and ataluren safety data, as well as the effectiveness of ataluren plus standard of care (SoC) in STRIDE versus SoC alone in the Cooperative International Neuromuscular Research Group (CINRG) Duchenne Natural History Study (DNHS). METHODS Patients are followed up from enrollment for at least 5 years or until study withdrawal. Propensity score matching was performed to identify STRIDE and CINRG DNHS patients who were comparable in established predictors of disease progression. RESULTS As of January 31, 2022, 307 patients were enrolled from 14 countries. Mean (standard deviation [SD]) ages at first symptoms and at genetic diagnosis were 2.9 (1.7) years and 4.5 (3.7) years, respectively. Mean (SD) duration of ataluren exposure was 1671 (56.8) days. Ataluren had a favorable safety profile; most treatment-emergent adverse events were mild or moderate and unrelated to ataluren. Kaplan-Meier analyses demonstrated that ataluren plus SoC significantly delayed age at loss of ambulation by 4 years (p < 0.0001) and age at decline to %-predicted forced vital capacity of < 60% and < 50% by 1.8 years (p = 0.0021) and 2.3 years (p = 0.0207), respectively, compared with SoC alone. CONCLUSION Long-term, real-world treatment with ataluren plus SoC delays several disease progression milestones in individuals with nmDMD. NCT02369731; registration date: February 24, 2015.
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Affiliation(s)
- Eugenio Mercuri
- Department of Pediatric Neurology, Catholic University, Rome, Italy.
- Centro Clinico Nemo, Fondazione Policlinico Agostino Gemelli IRCCS, Rome, Italy.
| | - Andrés Nascimento Osorio
- Neuromuscular Unit, Department of Neurology and Research in Neuromuscular Diseases, Institut de Recerca Sant Joan de Déu, Center for Biomedical Research Network on Rare Diseases (CIBERER), ISCIII, Barcelona, Spain
| | - Francesco Muntoni
- UCL Great Ormond Street Institute of Child Health, London, UK
- National Institute for Health Research, Great Ormond Street Institute of Child Health Biomedical Research Centre, University College London, London, UK
| | | | | | - Janbernd Kirschner
- Department of Neuropediatrics and Muscle Disorders, Medical Center-University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Már Tulinius
- Department of Pediatrics, Gothenburg University, Queen Silvia Children's Hospital, Gothenburg, Sweden
| | | | - Lauren P Morgenroth
- Therapeutic Research in Neuromuscular Disorders Solutions (TRiNDS), Pittsburgh, PA, USA
| | - Heather Gordish-Dressman
- Center for Genetic Medicine, Children's National Health System and the George Washington, Washington, DC, USA
| | | | | | | | | | - Erik K Henricson
- University of California Davis School of Medicine, Davis, CA, USA
| | - Craig M McDonald
- University of California Davis School of Medicine, Davis, CA, USA
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5
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Spelier S, van Doorn EPM, van der Ent CK, Beekman JM, Koppens MAJ. Readthrough compounds for nonsense mutations: bridging the translational gap. Trends Mol Med 2023; 29:297-314. [PMID: 36828712 DOI: 10.1016/j.molmed.2023.01.004] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/28/2022] [Accepted: 01/19/2023] [Indexed: 02/24/2023]
Abstract
Approximately 10% of all pathological mutations are nonsense mutations that are responsible for several severe genetic diseases for which no treatment regimens are currently available. The most widespread strategy for treating nonsense mutations is by enhancing ribosomal readthrough of premature termination codons (PTCs) to restore the production of the full-length protein. In the past decade several compounds with readthrough potential have been identified. However, although preclinical results on these compounds are promising, clinical studies have not yielded positive outcomes. We review preclinical and clinical research related to readthrough compounds and characterize factors that contribute to the observed translational gap.
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Affiliation(s)
- Sacha Spelier
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, 3584, EA, Utrecht, The Netherlands; Regenerative Medicine Utrecht, University Medical Center, Utrecht University, 3584, CT, Utrecht, The Netherlands
| | - Eveline P M van Doorn
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, 3584, EA, Utrecht, The Netherlands
| | - Cornelis K van der Ent
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, 3584, EA, Utrecht, The Netherlands; Regenerative Medicine Utrecht, University Medical Center, Utrecht University, 3584, CT, Utrecht, The Netherlands
| | - Jeffrey M Beekman
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, 3584, EA, Utrecht, The Netherlands; Regenerative Medicine Utrecht, University Medical Center, Utrecht University, 3584, CT, Utrecht, The Netherlands; Center for Living Technologies, Eindhoven-Wageningen-Utrecht Alliance, Utrecht, The Netherlands
| | - Martijn A J Koppens
- Department of Pediatric Respiratory Medicine, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, 3584, EA, Utrecht, The Netherlands; Regenerative Medicine Utrecht, University Medical Center, Utrecht University, 3584, CT, Utrecht, The Netherlands; Department of Metabolic Diseases, Wilhelmina Children's Hospital, University Medical Center, Utrecht University, 3584, EA, Utrecht, The Netherlands.
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6
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Recoding of Nonsense Mutation as a Pharmacological Strategy. Biomedicines 2023; 11:biomedicines11030659. [PMID: 36979640 PMCID: PMC10044939 DOI: 10.3390/biomedicines11030659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/18/2023] [Accepted: 02/20/2023] [Indexed: 02/24/2023] Open
Abstract
Approximately 11% of genetic human diseases are caused by nonsense mutations that introduce a premature termination codon (PTC) into the coding sequence. The PTC results in the production of a potentially harmful shortened polypeptide and activation of a nonsense-mediated decay (NMD) pathway. The NMD pathway reduces the burden of unproductive protein synthesis by lowering the level of PTC mRNA. There is an endogenous rescue mechanism that produces a full-length protein from a PTC mRNA. Nonsense suppression therapies aim to increase readthrough, suppress NMD, or are a combination of both strategies. Therefore, treatment with translational readthrough-inducing drugs (TRIDs) and NMD inhibitors may increase the effectiveness of PTC suppression. Here we discuss the mechanism of PTC readthrough and the development of novel approaches to PTC suppression. We also discuss the toxicity and bioavailability of therapeutics used to stimulate PTC readthrough.
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7
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Adachi H, Pan Y, He X, Chen JL, Klein B, Platenburg G, Morais P, Boutz P, Yu YT. Targeted pseudouridylation: An approach for suppressing nonsense mutations in disease genes. Mol Cell 2023; 83:637-651.e9. [PMID: 36764303 PMCID: PMC9975048 DOI: 10.1016/j.molcel.2023.01.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/18/2022] [Accepted: 01/05/2023] [Indexed: 02/11/2023]
Abstract
Nonsense mutations create premature termination codons (PTCs), activating the nonsense-mediated mRNA decay (NMD) pathway to degrade most PTC-containing mRNAs. The undegraded mRNA is translated, but translation terminates at the PTC, leading to no production of the full-length protein. This work presents targeted PTC pseudouridylation, an approach for nonsense suppression in human cells. Specifically, an artificial box H/ACA guide RNA designed to target the mRNA PTC can suppress both NMD and premature translation termination in various sequence contexts. Targeted pseudouridylation exhibits a level of suppression comparable with that of aminoglycoside antibiotic treatments. When targeted pseudouridylation is combined with antibiotic treatment, a much higher level of suppression is observed. Transfection of a disease model cell line (carrying a chromosomal PTC) with a designer guide RNA gene targeting the PTC also leads to nonsense suppression. Thus, targeted pseudouridylation is an RNA-directed gene-specific approach that suppresses NMD and concurrently promotes PTC readthrough.
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Affiliation(s)
- Hironori Adachi
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, Rochester, NY, USA
| | - Yi Pan
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, Rochester, NY, USA
| | - Xueyang He
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, Rochester, NY, USA
| | - Jonathan L Chen
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, Rochester, NY, USA
| | - Bart Klein
- ProQR Therapeutics, Leiden, the Netherlands
| | | | | | - Paul Boutz
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, Rochester, NY, USA; Center for Biomedical Informatics and Wilmot Cancer Institute, University of Rochester Medical Center, Rochester, NY, USA.
| | - Yi-Tao Yu
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, Rochester, NY, USA.
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8
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A High-Throughput Assay for In Vitro Determination of Release Factor-Dependent Peptide Release from a Pretermination Complex by Fluorescence Anisotropy-Application to Nonsense Suppressor Screening and Mechanistic Studies. Biomolecules 2023; 13:biom13020242. [PMID: 36830611 PMCID: PMC9953321 DOI: 10.3390/biom13020242] [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: 12/27/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 02/03/2023] Open
Abstract
Premature termination codons (PTCs) account for ~12% of all human disease mutations. Translation readthrough-inducing drugs (TRIDs) are prominent among the several therapeutic approaches being used to overcome PTCs. Ataluren is the only TRID that has been approved for treating patients suffering from a PTC disease, Duchenne muscular dystrophy, but it gives variable readthrough results in cells isolated from patients suffering from other PTC diseases. We recently elucidated ataluren's mechanism of action as a competitive inhibitor of release factor complex (RFC) catalysis of premature termination and identified ataluren's binding sites on the ribosome responsible for such an inhibition. These results suggest the possibility of discovering new TRIDs, which would retain ataluren's low toxicity while displaying greater potency and generality in stimulating readthrough via the inhibition of termination. Here we present a detailed description of a new in vitro plate reader assay that we are using both to screen small compound libraries for the inhibition of RFC-dependent peptide release and to better understand the influence of termination codon identity and sequence context on RFC activity.
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9
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The Pathology of Primary Familial Brain Calcification: Implications for Treatment. Neurosci Bull 2022; 39:659-674. [PMID: 36469195 PMCID: PMC10073384 DOI: 10.1007/s12264-022-00980-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 07/10/2022] [Indexed: 12/08/2022] Open
Abstract
AbstractPrimary familial brain calcification (PFBC) is an inherited neurodegenerative disorder mainly characterized by progressive calcium deposition bilaterally in the brain, accompanied by various symptoms, such as dystonia, ataxia, parkinsonism, dementia, depression, headaches, and epilepsy. Currently, the etiology of PFBC is largely unknown, and no specific prevention or treatment is available. During the past 10 years, six causative genes (SLC20A2, PDGFRB, PDGFB, XPR1, MYORG, and JAM2) have been identified in PFBC. In this review, considering mechanistic studies of these genes at the cellular level and in animals, we summarize the pathogenesis and potential preventive and therapeutic strategies for PFBC patients. Our systematic analysis suggests a classification for PFBC genetic etiology based on several characteristics, provides a summary of the known composition of brain calcification, and identifies some potential therapeutic targets for PFBC.
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10
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Leung A, Sacristan-Reviriego A, Perdigão PRL, Sai H, Georgiou M, Kalitzeos A, Carr AJF, Coffey PJ, Michaelides M, Bainbridge J, Cheetham ME, van der Spuy J. Investigation of PTC124-mediated translational readthrough in a retinal organoid model of AIPL1-associated Leber congenital amaurosis. Stem Cell Reports 2022; 17:2187-2202. [PMID: 36084639 PMCID: PMC9561542 DOI: 10.1016/j.stemcr.2022.08.005] [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: 01/31/2022] [Revised: 08/10/2022] [Accepted: 08/12/2022] [Indexed: 10/26/2022] Open
Abstract
Leber congenital amaurosis type 4 (LCA4), caused by AIPL1 mutations, is characterized by severe sight impairment in infancy and rapidly progressing degeneration of photoreceptor cells. We generated retinal organoids using induced pluripotent stem cells (iPSCs) from renal epithelial cells obtained from four children with AIPL1 nonsense mutations. iPSC-derived photoreceptors exhibited the molecular hallmarks of LCA4, including undetectable AIPL1 and rod cyclic guanosine monophosphate (cGMP) phosphodiesterase (PDE6) compared with control or CRISPR-corrected organoids. Increased levels of cGMP were detected. The translational readthrough-inducing drug (TRID) PTC124 was investigated as a potential therapeutic agent. LCA4 retinal organoids exhibited low levels of rescue of full-length AIPL1. However, this was insufficient to fully restore PDE6 in photoreceptors and reduce cGMP. LCA4 retinal organoids are a valuable platform for in vitro investigation of novel therapeutic agents.
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Affiliation(s)
- Amy Leung
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | | | | | - Hali Sai
- UCL Institute of Ophthalmology, London EC1V 9EL, UK
| | - Michalis Georgiou
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
| | - Angelos Kalitzeos
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
| | | | | | - Michel Michaelides
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
| | - James Bainbridge
- UCL Institute of Ophthalmology, London EC1V 9EL, UK; Moorfields Eye Hospital NHS Foundation Trust, London EC1V 2PD, UK
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11
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Bowling A, Eastman A, Merlo C, Lin G, West N, Patel S, Cutting G, Sharma N. Downstream Alternate Start Site Allows N-Terminal Nonsense Variants to Escape NMD and Results in Functional Recovery by Readthrough and Modulator Combination. J Pers Med 2022; 12:jpm12091448. [PMID: 36143233 PMCID: PMC9504986 DOI: 10.3390/jpm12091448] [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: 08/09/2022] [Revised: 08/26/2022] [Accepted: 08/31/2022] [Indexed: 11/23/2022] Open
Abstract
Genetic variants that introduce premature termination codons (PTCs) have remained difficult to therapeutically target due to lack of protein product. Nonsense mediated mRNA decay (NMD) targets PTC-bearing transcripts to reduce the potentially damaging effects of truncated proteins. Readthrough compounds have been tested on PTC-generating variants in attempt to permit translation through a premature stop. However, readthrough compounds have not proved efficacious in a clinical setting due to lack of stable mRNA. Here, we investigate N-terminal variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which have been shown to escape NMD, potentially through a mechanism of alternative translation initiation at downstream AUG codons. We hypothesized that N-terminal variants in CFTR that evade NMD will produce stable transcript, allowing CFTR function to be restored by a combination of readthrough and protein modulator therapy. We investigate this using two cell line models expressing CFTR-expression minigenes (EMG; HEK293s and CFBEs) and primary human nasal epithelial (NE) cells, and we test readthrough compounds G418 and ELX-02 in combination with CFTR protein modulators. HEK293 cells expressing the variants E60X and L88X generate CFTR-specific core glycosylated products that are consistent with downstream translation initiation. Mutation of downstream methionines at codons 150 and 152 does not result in changes in CFTR protein processing in cells expressing L88X-CFTR-EMG. However, mutation of methionine at 265 results in loss of detectable CFTR protein in cells expressing E60X, L88X, and Y122X CFTR-EMGs, indicating that downstream translation initiation is occurring at the AUG codon at position M265. In HEK293 stable cells harboring L88X, treatment with readthrough compounds alone allows for formation of full-length, but misfolded CFTR protein. Upon addition of protein modulators in combination with readthrough, we observe formation of mature, complex-glycosylated CFTR. In CFBE and NE cells, addition of readthrough ELX-02 and modulator therapy results in substantial recovery of CFTR function. Our work indicates that N-terminal variants generate stable CFTR transcript due to translation initiation at a downstream AUG codon. Thus, individuals with CF bearing 5′ nonsense variants that evade NMD are ideal candidates for treatment with clinically safe readthrough compounds and modulator therapy.
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Affiliation(s)
- Alyssa Bowling
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Alice Eastman
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Christian Merlo
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins Hospital, Baltimore, MD 21205, USA
| | - Gabrielle Lin
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Natalie West
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins Hospital, Baltimore, MD 21205, USA
| | - Shivani Patel
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Johns Hopkins Hospital, Baltimore, MD 21205, USA
| | - Garry Cutting
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Neeraj Sharma
- McKusick-Nathans Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
- Correspondence:
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12
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Functional restoration of mouse Nf1 nonsense alleles in differentiated cultured neurons. J Hum Genet 2022; 67:661-668. [PMID: 35945271 DOI: 10.1038/s10038-022-01072-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/27/2022] [Accepted: 07/27/2022] [Indexed: 11/09/2022]
Abstract
Neurofibromatosis type 1 (NF1), one of the most common autosomal dominant genetic disorders, is caused by mutations in the NF1 gene. NF1 patients have a wide variety of manifestations with a subset at high risk for the development of tumors in the central nervous system (CNS). Nonsense mutations that result in the synthesis of truncated NF1 protein (neurofibromin) are strongly associated with CNS tumors. Therapeutic nonsense suppression with small molecule drugs is a potentially powerful approach to restore the expression of genes harboring nonsense mutations. Ataluren is one such drug that has been shown to restore full-length functional protein in several models of nonsense mutation diseases, as well as in patients with nonsense mutation Duchenne muscular dystrophy. To test ataluren's potential applicability to NF1 nonsense mutations associated with CNS tumors, we generated a homozygous Nf1R683X/R683X-3X-FLAG mouse embryonic stem (mES) cell line which recapitulates an NF1 patient nonsense mutation (c.2041 C > T; p.Arg681X). We differentiated Nf1R683X/R683X-3X-FLAG mES cells into cortical neurons in vitro, treated the cells with ataluren, and demonstrated that ataluren can promote readthrough of the nonsense mutation at codon 683 of Nf1 mRNA in neural cells. The resulting full-length protein is able to reduce the cellular level of hyperactive phosphorylated ERK (pERK), a RAS effector normally suppressed by the NF1 protein.
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13
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Ataluren suppresses a premature termination codon in an MPS I-H mouse. J Mol Med (Berl) 2022; 100:1223-1235. [PMID: 35857082 PMCID: PMC9329424 DOI: 10.1007/s00109-022-02232-0] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/26/2022] [Accepted: 06/28/2022] [Indexed: 11/26/2022]
Abstract
Abstarct Suppressing translation termination at premature termination codons (PTCs), termed readthrough, is a potential therapy for genetic diseases caused by nonsense mutations. Ataluren is a compound that has shown promise for clinical use as a readthrough agent. However, some reports suggest that ataluren is ineffective at suppressing PTCs. To further evaluate the effectiveness of ataluren as a readthrough agent, we examined its ability to suppress PTCs in a variety of previously untested models. Using NanoLuc readthrough reporters expressed in two different cell types, we found that ataluren stimulated a significant level of readthrough. We also explored the ability of ataluren to suppress a nonsense mutation associated with Mucopolysaccharidosis I-Hurler (MPS I-H), a genetic disease that is caused by a deficiency of α-L-iduronidase that leads to lysosomal accumulation of glycosaminoglycans (GAGs). Using mouse embryonic fibroblasts (MEFs) derived from Idua-W402X mice, we found that ataluren partially rescued α-L-iduronidase function and significantly reduced GAG accumulation relative to controls. Two-week oral administration of ataluren to Idua-W402X mice led to significant GAG reductions in most tissues compared to controls. Together, these data reveal important details concerning the efficiency of ataluren as a readthrough agent and the mechanisms that govern its ability to suppress PTCs. Key messages Ataluren promotes readthrough of PTCs in a wide variety of contexts. Ataluren reduces glycosaminoglyan storage in MPS I-H cell and mouse models. Ataluren has a bell-shaped dose–response curve and a narrow effective range.
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Huang S, Bhattacharya A, Ghelfi MD, Li H, Fritsch C, Chenoweth DM, Goldman YE, Cooperman BS. Ataluren binds to multiple protein synthesis apparatus sites and competitively inhibits release factor-dependent termination. Nat Commun 2022; 13:2413. [PMID: 35523781 PMCID: PMC9076611 DOI: 10.1038/s41467-022-30080-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 04/12/2022] [Indexed: 12/15/2022] Open
Abstract
Genetic diseases are often caused by nonsense mutations, but only one TRID (translation readthrough inducing drug), ataluren, has been approved for clinical use. Ataluren inhibits release factor complex (RFC) termination activity, while not affecting productive binding of near-cognate ternary complex (TC, aa-tRNA.eEF1A.GTP). Here we use photoaffinity labeling to identify two sites of ataluren binding within rRNA, proximal to the decoding center (DC) and the peptidyl transfer center (PTC) of the ribosome, which are directly responsible for ataluren inhibition of termination activity. A third site, within the RFC, has as yet unclear functional consequences. Using single molecule and ensemble fluorescence assays we also demonstrate that termination proceeds via rapid RFC-dependent hydrolysis of peptidyl-tRNA followed by slow release of peptide and tRNA from the ribosome. Ataluren is an apparent competitive inhibitor of productive RFC binding, acting at or before the hydrolysis step. We propose that designing more potent TRIDs which retain ataluren's low toxicity should target areas of the RFC binding site proximal to the DC and PTC which do not overlap the TC binding site.
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Affiliation(s)
- Shijie Huang
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
- GSK, 14200 Shady Grove Rd, Rockville, MD, 20850, USA
| | - Arpan Bhattacharya
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Mikel D Ghelfi
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Hong Li
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Clark Fritsch
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - David M Chenoweth
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Yale E Goldman
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Barry S Cooperman
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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Potapova NA. Nonsense Mutations in Eukaryotes. BIOCHEMISTRY. BIOKHIMIIA 2022; 87:400-412. [PMID: 35790376 DOI: 10.1134/s0006297922050029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 02/14/2022] [Accepted: 03/22/2022] [Indexed: 06/15/2023]
Abstract
Nonsense mutations are a type of mutations which results in a premature termination codon occurrence. In general, these mutations have been considered to be among the most harmful ones which lead to premature protein translation termination and result in shortened nonfunctional polypeptide. However, there is evidence that not all nonsense mutations are harmful as well as some molecular mechanisms exist which allow to avoid pathogenic effects of these mutations. This review addresses relevant information on nonsense mutations in eukaryotic genomes, characteristics of these mutations, and different molecular mechanisms preventing or mitigating harmful effects thereof.
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Affiliation(s)
- Nadezhda A Potapova
- Kharkevich Institute for Information Transmission Problems (IITP), Russian Academy of Sciences, Moscow, 127051, Russia.
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16
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Jafari E, Rezaeinasab R, Khodarahmi G. Quinazolinone-based hybrids with diverse biological activities: A mini-review. JOURNAL OF RESEARCH IN MEDICAL SCIENCES 2022; 27:68. [PMID: 36353342 PMCID: PMC9639715 DOI: 10.4103/jrms.jrms_1025_21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 02/12/2022] [Accepted: 04/04/2022] [Indexed: 11/16/2022]
Abstract
Quinazolinone and quinazoline have been shown different pharmacological activities, namely anticancer, anti-inflammatory, anti-hyperlipidemia, analgesic, antihypertensive, and antibacterial. On the other hand, molecular hybridization is a structural modification technique in the design of new ligands which consist of two or more pharmacologically active molecules in one structure. Therefore, due to the importance of the biological activities of quinazolinones for the development of new therapeutic agents, this review emphasizes current findings on various quinazolinone-based hybrids in medicinal chemistry. Moreover, it highlights the biological activities and structure-activity relationship of these hybrids.
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Schneider N, Sundaresan Y, Gopalakrishnan P, Beryozkin A, Hanany M, Levanon EY, Banin E, Ben-Aroya S, Sharon D. Inherited retinal diseases: Linking genes, disease-causing variants, and relevant therapeutic modalities. Prog Retin Eye Res 2021; 89:101029. [PMID: 34839010 DOI: 10.1016/j.preteyeres.2021.101029] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 11/11/2021] [Accepted: 11/16/2021] [Indexed: 12/11/2022]
Abstract
Inherited retinal diseases (IRDs) are a clinically complex and heterogenous group of visual impairment phenotypes caused by pathogenic variants in at least 277 nuclear and mitochondrial genes, affecting different retinal regions, and depleting the vision of affected individuals. Genes that cause IRDs when mutated are unique by possessing differing genotype-phenotype correlations, varying inheritance patterns, hypomorphic alleles, and modifier genes thus complicating genetic interpretation. Next-generation sequencing has greatly advanced the identification of novel IRD-related genes and pathogenic variants in the last decade. For this review, we performed an in-depth literature search which allowed for compilation of the Global Retinal Inherited Disease (GRID) dataset containing 4,798 discrete variants and 17,299 alleles published in 31 papers, showing a wide range of frequencies and complexities among the 194 genes reported in GRID, with 65% of pathogenic variants being unique to a single individual. A better understanding of IRD-related gene distribution, gene complexity, and variant types allow for improved genetic testing and therapies. Current genetic therapeutic methods are also quite diverse and rely on variant identification, and range from whole gene replacement to single nucleotide editing at the DNA or RNA levels. IRDs and their suitable therapies thus require a range of effective disease modelling in human cells, granting insight into disease mechanisms and testing of possible treatments. This review summarizes genetic and therapeutic modalities of IRDs, provides new analyses of IRD-related genes (GRID and complexity scores), and provides information to match genetic-based therapies such as gene-specific and variant-specific therapies to the appropriate individuals.
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Affiliation(s)
- Nina Schneider
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, 91120, Israel
| | - Yogapriya Sundaresan
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, 91120, Israel
| | - Prakadeeswari Gopalakrishnan
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, 91120, Israel
| | - Avigail Beryozkin
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, 91120, Israel
| | - Mor Hanany
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, 91120, Israel
| | - Erez Y Levanon
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Eyal Banin
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, 91120, Israel
| | - Shay Ben-Aroya
- The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan, 5290002, Israel
| | - Dror Sharon
- Department of Ophthalmology, Hadassah Medical Center, Faculty of Medicine, The Hebrew University of Jerusalem, 91120, Israel.
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Bayat F, Homami SS, Monzavi A, Talei Bavil Olyai MR. A combined molecular docking and molecular dynamics simulation approach to probing the host–guest interactions of Ataluren with natural and modified cyclodextrins. MOLECULAR SIMULATION 2021. [DOI: 10.1080/08927022.2021.1991921] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Farhad Bayat
- Deptartment of Applied Chemistry, Faculty of Science, South Tehran Branch, Islamic Azad University, Tehran, Iran
- Department of Biotechnology, Pasteur Institute of Iran, Tehran, Iran
| | - Seyed Saied Homami
- Deptartment of Applied Chemistry, Faculty of Science, South Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Amirhossein Monzavi
- Deptartment of Polymer and Textile Engineering, South Tehran Branch, Islamic Azad University, Tehran, Iran
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Triana-Fonseca P, Parada-Márquez JF, Silva-Aldana CT, Zambrano-Arenas D, Arias-Gomez LL, Morales-Fonseca N, Medina-Méndez E, Restrepo CM, Silgado-Guzmán DF, Fonseca-Mendoza DJ. Genetic Profile of the Dystrophin Gene Reveals New Mutations in Colombian Patients Affected with Muscular Dystrophinopathy. APPLICATION OF CLINICAL GENETICS 2021; 14:399-408. [PMID: 34629887 PMCID: PMC8493106 DOI: 10.2147/tacg.s317721] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/31/2021] [Indexed: 11/23/2022]
Abstract
Background Duchenne and Becker muscular dystrophies (DMD/BMD) are the most common human dystrophinopathies with recessive X-linked inheritance. Dystrophin gene deletions and duplications are the most common mutations, followed by point mutations. The aim of this study is to characterize the mutational profile of the dystrophin gene in Colombian patients with DMD/BMD. Material and Methods Mutational profiling was determined in 69 affected patients using Sanger sequencing, next-generation sequencing (NGS) and/or multiplex ligation dependent-probes amplification (MLPA). Genetic variants were classified according to molecular consequence and new variants were determined through database and literature analysis. Results Mutational profile in affected patients revealed that large deletions/duplications analyzed by MLPA accounted for 72.5% of all genetic variations. By using Sanger sequencing or NGS, we identified point mutations in 15.9% and small deletions in 11.6% of the patients. New mutations were found, most of them were point mutations or small deletions (10.1%). Conclusion Our results described the genetic profile of the dystrophin gene in Colombian patients with DMD and contribute to efforts to identify molecular variants in Latin American populations. For our population, 18.8% of cases could be treated with FDA or MDA approved molecular therapies based on specific mutations. These data contribute to the establishment of appropriate genetic counseling and potential treatment.
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Affiliation(s)
| | | | - Claudia T Silva-Aldana
- Department of Molecular Diagnosis, Genética Molecular de Colombia SAS, Bogotá, DC, Colombia
| | | | | | | | - Esteban Medina-Méndez
- Department of Molecular Diagnosis, Genética Molecular de Colombia SAS, Bogotá, DC, Colombia
| | - Carlos M Restrepo
- Center for Research in Genetics and Genomics - CIGGUR, GENIUROS Research Group, School of Medicine and Health Sciences, Universidad Del Rosario, Bogotá, DC, Colombia
| | | | - Dora Janeth Fonseca-Mendoza
- Center for Research in Genetics and Genomics - CIGGUR, GENIUROS Research Group, School of Medicine and Health Sciences, Universidad Del Rosario, Bogotá, DC, Colombia
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McDonald CM, Wei LJ, Flanigan KM, Elfring G, Trifillis P, Muntoni F. Evaluating longitudinal therapy effects via the North Star Ambulatory Assessment. Muscle Nerve 2021; 64:614-619. [PMID: 34383312 PMCID: PMC9290940 DOI: 10.1002/mus.27396] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 08/03/2021] [Accepted: 08/07/2021] [Indexed: 11/08/2022]
Abstract
INTRODUCTION/AIMS In comparative studies, treatment effects are typically evaluated at a specific time point. When data are collected periodically, an alternative, clinically meaningful approach could be used to assess the totality of treatment effects. We applied a well-developed analytical procedure for evaluating longitudinal treatment effects using North Star Ambulatory Assessment (NSAA) data for illustration. METHODS The NSAA comprises 17 scorable items/outcomes that measure changes in motor function. Using NSAA data from the published ataluren phase 3, randomized, placebo-controlled trial (NCT01826487), cumulative counts of failures to perform each item (transition from 2/1 [able/impaired] to 0 [unable]) were collected at specified time points for each patient over 48 wk. Treatment group-wise mean cumulative item failure count curves were constructed, comparing ataluren versus placebo and deflazacort versus prednisone/prednisolone among placebo-treated patients. The steeper the curve, the worse the outcome. A clinically meaningful summary of the between-group difference was provided for each comparison. RESULTS The curve was uniformly steeper for placebo than ataluren after 16 wk and for prednisone/prednisolone than deflazacort after 8 wk. The two curves in each comparison continued to diverge thereafter, indicating sustained treatment benefits over time. Using a unique analytical approach, cumulative failure rates were reduced, on average, by 27% for ataluren versus placebo (rate ratio, 0.73; 95% confidence interval [CI], 0.55-0.97; p = .027) and 28% for deflazacort versus prednisone/prednisolone (rate ratio, 0.72; 95% CI, 0.53-0.96; p = .028). DISCUSSION Unlike fixed-time analyses, this analytical approach enabled demonstration of cumulative, longitudinal treatment effects over time using repeatedly measured NSAA observations.
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Affiliation(s)
- Craig M McDonald
- Physical Medicine & Rehabilitation, University of California Davis, Davis, California, USA
| | - Lee-Jen Wei
- Harvard University, Boston, Massachusetts, USA
| | | | - Gary Elfring
- PTC Therapeutics Inc, South Plainfield, New Jersey, USA
| | | | - Francesco Muntoni
- University College London Great Ormond Street Institute of Child Health and NIHR Biomedical Research Centre, London, UK
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Ataluren-Promising Therapeutic Premature Termination Codon Readthrough Frontrunner. Pharmaceuticals (Basel) 2021; 14:ph14080785. [PMID: 34451881 PMCID: PMC8398184 DOI: 10.3390/ph14080785] [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: 07/10/2021] [Revised: 07/30/2021] [Accepted: 08/06/2021] [Indexed: 02/08/2023] Open
Abstract
Around 12% of hereditary disease-causing mutations are in-frame nonsense mutations. The expression of genes containing nonsense mutations potentially leads to the production of truncated proteins with residual or virtually no function. However, the translation of transcripts containing premature stop codons resulting in full-length protein expression can be achieved using readthrough agents. Among them, only ataluren was approved in several countries to treat nonsense mutation Duchenne muscular dystrophy (DMD) patients. This review summarizes ataluren’s journey from its identification, via first in vitro activity experiments, to clinical trials in DMD, cystic fibrosis, and aniridia. Additionally, data on its pharmacokinetics and mechanism of action are presented. The range of diseases with underlying nonsense mutations is described for which ataluren therapy seems to be promising. What is more, experiments in which ataluren did not show its readthrough activity are also included, and reasons for their failures are discussed.
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22
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Xie Z, Jiang J, Cao L, Jiang M, Yang F, Ma Z, Wang Z, Ruan C, Liu H, Zhou L. Nonsense-mediated mRNA decay efficiency influences bleeding severity in ITGA2B c.2659C > T (p.Q887X) knock-in mice. Clin Genet 2021; 100:213-218. [PMID: 33928629 DOI: 10.1111/cge.13975] [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: 01/12/2021] [Revised: 04/22/2021] [Accepted: 04/26/2021] [Indexed: 11/28/2022]
Abstract
Glanzmann's thrombasthenia (GT) is a severe hemorrhagic disease. It is caused by mutations in ITGA2B or ITGB3, which are the respective genes encoding integrin αIIb and β3. Despite widespread mutational analysis, the mechanisms underlying the extensive variability in bleeding severity observed among affected individuals remains poorly understood. In order to explore the mechanisms conferring for bleeding heterogeneity, three GT patients with ITGA2B c.2671C > T (p.Q891X) who possessed different bleeding scores were studied. Analysis showed that there was significant difference in nonsense-mediated mRNA decay (NMD) efficiency among the three patients. These differences positively correlated with their bleeding score. Next, a knock-in mouse model (KI mice) with the ITGA2B c.2659C > T (p.Q887X) was generated using CRISPR/Cas9. Importantly, this mutation is homologous to ITGA2B c.2671C > T (p.Q891X) in humans. The bleeding time of KI mice was significantly in comparison to the wide-type mice. Interestingly, bleeding was stopped after treatment with caffeine, which is a known NMD inhibitor. This suggests that NMD efficiency potentially influences bleeding severity in ITGA2B c.2659C > T (p.Q887X) KI mice.
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Affiliation(s)
- Zhanli Xie
- Department of Nuclear Medicine, Institute of Clinical Medicine Research, Suzhou Hospital (West District), Affiliated to Nanjing Medical University, Suzhou Science and Technology Town Hospital, Suzhou, China
- Hematology department, Affiliated Hospital of Nantong University, Nantong, China
| | - Jiang Jiang
- Department of Nuclear Medicine, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Lijuan Cao
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis & Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Miao Jiang
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis & Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Fei Yang
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis & Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhenni Ma
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis & Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhaoyue Wang
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis & Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Changgeng Ruan
- Jiangsu Institute of Hematology, Key Laboratory of Thrombosis & Hemostasis of Ministry of Health, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Hong Liu
- Hematology department, Affiliated Hospital of Nantong University, Nantong, China
| | - Lu Zhou
- Hematology department, Affiliated Hospital of Nantong University, Nantong, China
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Genetics, pathogenesis and therapeutic developments for Usher syndrome type 2. Hum Genet 2021; 141:737-758. [PMID: 34331125 DOI: 10.1007/s00439-021-02324-w] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 07/24/2021] [Indexed: 12/28/2022]
Abstract
Usher syndrome (USH) is a rare, autosomal recessively inherited disorder resulting in a combination of sensorineural hearing loss and a progressive loss of vision resulting from retinitis pigmentosa (RP), occasionally accompanied by an altered vestibular function. More and more evidence is building up indicating that also sleep deprivation, olfactory dysfunction, deficits in tactile perception and reduced sperm motility are part of the disease etiology. USH can be clinically classified into three different types, of which Usher syndrome type 2 (USH2) is the most prevalent. In this review, we, therefore, assess the genetic and clinical aspects, available models and therapeutic developments for USH2. Mutations in USH2A, ADGRV1 and WHRN have been described to be responsible for USH2, with USH2A being the most frequently mutated USH-associated gene, explaining 50% of all cases. The proteins encoded by the USH2 genes together function in a dynamic protein complex that, among others, is found at the photoreceptor periciliary membrane and at the base of the hair bundles of inner ear hair cells. To unravel the pathogenic mechanisms underlying USH2, patient-derived cellular models and animal models including mouse, zebrafish and drosophila, have been generated that all in part mimic the USH phenotype. Multiple cellular and genetic therapeutic approaches are currently under development for USH2, mainly focused on preserving or partially restoring the visual function of which one is already in the clinical phase. These developments are opening a new gate towards a possible treatment for USH2 patients.
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Ataluren and aminoglycosides stimulate read-through of nonsense codons by orthogonal mechanisms. Proc Natl Acad Sci U S A 2021; 118:2020599118. [PMID: 33414181 PMCID: PMC7812769 DOI: 10.1073/pnas.2020599118] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Nonsense mutations giving rise to premature stop codons (PSCs) cause many diseases, creating the need to develop safe and effective translational read-through–inducing drugs (TRIDs). The current best-characterized TRIDs are ataluren and aminoglycosides. Only ataluren has been approved for clinical use, albeit in a limited context. Here, we provide rate measurements of elementary steps in a single eukaryotic translation elongation cycle, allowing us to demonstrate that ataluren and the aminoglycoside G418 employ orthogonal mechanisms in stimulating PSC read-through: ataluren by inhibiting release factor-dependent termination of protein synthesis and G418 by increasing functional near-cognate transfer RNA mispairing, which permits continuation of synthesis. We conclude that development of new TRIDs combatting PSC diseases should prioritize those directed toward inhibiting termination. During protein synthesis, nonsense mutations, resulting in premature stop codons (PSCs), produce truncated, inactive protein products. Such defective gene products give rise to many diseases, including cystic fibrosis, Duchenne muscular dystrophy (DMD), and some cancers. Small molecule nonsense suppressors, known as TRIDs (translational read-through–inducing drugs), stimulate stop codon read-through. The best characterized TRIDs are ataluren, which has been approved by the European Medicines Agency for the treatment of DMD, and G418, a structurally dissimilar aminoglycoside. Previously [1], we applied a highly purified in vitro eukaryotic translation system to demonstrate that both aminoglycosides like G418 and more hydrophobic molecules like ataluren stimulate read-through by direct interaction with the cell’s protein synthesis machinery. Our results suggested that they might do so by different mechanisms. Here, we pursue this suggestion through a more-detailed investigation of ataluren and G418 effects on read-through. We find that ataluren stimulation of read-through derives exclusively from its ability to inhibit release factor activity. In contrast, G418 increases functional near-cognate tRNA mispairing with a PSC, resulting from binding to its tight site on the ribosome, with little if any effect on release factor activity. The low toxicity of ataluren suggests that development of new TRIDs exclusively directed toward inhibiting termination should be a priority in combatting PSC diseases. Our results also provide rate measurements of some of the elementary steps during the eukaryotic translation elongation cycle, allowing us to determine how these rates are modified when cognate tRNA is replaced by near-cognate tRNA ± TRIDs.
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Hosseini-Farahabadi S, Baradaran-Heravi A, Zimmerman C, Choi K, Flibotte S, Roberge M. Small molecule Y-320 stimulates ribosome biogenesis, protein synthesis, and aminoglycoside-induced premature termination codon readthrough. PLoS Biol 2021; 19:e3001221. [PMID: 33939688 PMCID: PMC8118496 DOI: 10.1371/journal.pbio.3001221] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 05/13/2021] [Accepted: 04/09/2021] [Indexed: 11/18/2022] Open
Abstract
Premature termination codons (PTC) cause over 10% of genetic disease cases. Some aminoglycosides that bind to the ribosome decoding center can induce PTC readthrough and restore low levels of full-length functional proteins. However, concomitant inhibition of protein synthesis limits the extent of PTC readthrough that can be achieved by aminoglycosides like G418. Using a cell-based screen, we identified a small molecule, the phenylpyrazoleanilide Y-320, that potently enhances TP53, DMD, and COL17A1 PTC readthrough by G418. Unexpectedly, Y-320 increased cellular protein levels and protein synthesis, measured by SYPRO Ruby protein staining and puromycin labeling, as well as ribosome biogenesis measured using antibodies to rRNA and ribosomal protein S6. Y-320 did not increase the rate of translation elongation and it exerted its effects independently of mTOR signaling. At the single cell level, exposure to Y-320 and G418 increased ribosome content and protein synthesis which correlated strongly with PTC readthrough. As a single agent, Y-320 did not affect translation fidelity measured using a luciferase reporter gene but it enhanced misincorporation by G418. RNA-seq data showed that Y-320 up-regulated the expression of CXC chemokines CXCL10, CXCL8, CXCL2, CXCL11, CXCL3, CXCL1, and CXCL16. Several of these chemokines exert their cellular effects through the receptor CXCR2 and the CXCR2 antagonist SB225002 reduced cellular protein levels and PTC readthrough in cells exposed to Y-320 and G418. These data show that the self-limiting nature of PTC readthrough by G418 can be compensated by Y-320, a potent enhancer of PTC readthrough that increases ribosome biogenesis and protein synthesis. They also support a model whereby increased PTC readthrough is enabled by increased protein synthesis mediated by an autocrine chemokine signaling pathway. The findings also raise the possibility that inflammatory processes affect cellular propensity to readthrough agents and that immunomodulatory drugs like Y-320 might find application in PTC readthrough therapy.
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Affiliation(s)
- Sara Hosseini-Farahabadi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Alireza Baradaran-Heravi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Carla Zimmerman
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kunho Choi
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Stephane Flibotte
- UBC/LSI Bioinformatics Facility, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michel Roberge
- Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada
- * E-mail:
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Martins-Dias P, Romão L. Nonsense suppression therapies in human genetic diseases. Cell Mol Life Sci 2021; 78:4677-4701. [PMID: 33751142 PMCID: PMC11073055 DOI: 10.1007/s00018-021-03809-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Revised: 02/06/2021] [Accepted: 03/05/2021] [Indexed: 02/06/2023]
Abstract
About 11% of all human disease-associated gene lesions are nonsense mutations, resulting in the introduction of an in-frame premature translation-termination codon (PTC) into the protein-coding gene sequence. When translated, PTC-containing mRNAs originate truncated and often dysfunctional proteins that might be non-functional or have gain-of-function or dominant-negative effects. Therapeutic strategies aimed at suppressing PTCs to restore deficient protein function-the so-called nonsense suppression (or PTC readthrough) therapies-have the potential to provide a therapeutic benefit for many patients and in a broad range of genetic disorders, including cancer. These therapeutic approaches comprise the use of translational readthrough-inducing compounds that make the translational machinery recode an in-frame PTC into a sense codon. However, most of the mRNAs carrying a PTC can be rapidly degraded by the surveillance mechanism of nonsense-mediated decay (NMD), thus decreasing the levels of PTC-containing mRNAs in the cell and their availability for PTC readthrough. Accordingly, the use of NMD inhibitors, or readthrough-compound potentiators, may enhance the efficiency of PTC suppression. Here, we review the mechanisms of PTC readthrough and their regulation, as well as the recent advances in the development of novel approaches for PTC suppression, and their role in personalized medicine.
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Affiliation(s)
- Patrícia Martins-Dias
- Department of Human Genetics, Instituto Nacional de Saúde Doutor Ricardo Jorge, Av. Padre Cruz, 1649-016, Lisbon, Portugal
- Faculty of Sciences, BioISI-Biosystems and Integrative Sciences Institute, University of Lisboa, 1749-016, Lisbon, Portugal
| | - Luísa Romão
- Department of Human Genetics, Instituto Nacional de Saúde Doutor Ricardo Jorge, Av. Padre Cruz, 1649-016, Lisbon, Portugal.
- Faculty of Sciences, BioISI-Biosystems and Integrative Sciences Institute, University of Lisboa, 1749-016, Lisbon, Portugal.
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27
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Seo K, Kim EK, Choi J, Kim DS, Shin JH. Functional recovery of a novel knockin mouse model of dysferlinopathy by readthrough of nonsense mutation. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2021; 21:702-709. [PMID: 34141825 PMCID: PMC8181533 DOI: 10.1016/j.omtm.2021.04.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 04/27/2021] [Indexed: 12/04/2022]
Abstract
Biallelic mutations in the dysferlin gene cause limb-girdle muscular dystrophy 2B or Miyoshi distal myopathy. We found that nonsense mutations are the most common mutation type among Korean patients with dysferlinopathy; more than half of the patients have at least one nonsense allele, which may be amenable to readthrough therapy. We generated a knockin mouse, dqx, harboring DYSF p.Q832∗ mutation. Homozygous dqx mice lacked dysferlin in skeletal muscle, while 2 weeks of oral ataluren restored dysferlin expression and ameliorated skeletal muscle pathology. Their physical performance improved, and protection against eccentric contractions was noted. The improvement was most evident in mice treated with oral ataluren of 0.9 mg/mL. These improvements were sustained for 8 weeks in ataluren-treated dqx mice, while the parameters of A/J mice treated with ataluren over the same period did not improve. These results support that readthrough therapy by oral ataluren may also be applicable to dysferlinopathy patients with nonsense mutation.
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Affiliation(s)
- Kyowon Seo
- Neurology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnamdo 50612, Republic of Korea
| | - Eun Kyoung Kim
- Neurology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnamdo 50612, Republic of Korea
| | - Jaeil Choi
- Neurology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnamdo 50612, Republic of Korea
| | - Dae-Seong Kim
- Neurology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnamdo 50612, Republic of Korea
| | - Jin-Hong Shin
- Neurology, Pusan National University Yangsan Hospital, Yangsan, Gyeongsangnamdo 50612, Republic of Korea
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28
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Kong R, Ma J, Hwang S, Moon YC, Welch EM, Weetall M, Colacino JM, Almstead N, Babiak J, Goodwin E. In vitro metabolism, reaction phenotyping, enzyme kinetics, CYP inhibition and induction potential of ataluren. Pharmacol Res Perspect 2021; 8:e00576. [PMID: 32196986 PMCID: PMC7083565 DOI: 10.1002/prp2.576] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/24/2020] [Accepted: 02/24/2020] [Indexed: 01/06/2023] Open
Abstract
Ataluren promotes ribosomal readthrough of premature termination codons in mRNA which result from nonsense mutations. In vitro studies were performed to characterize the metabolism and enzyme kinetics of ataluren and its interaction potential with CYP enzymes. Incubation of [14C]‐ataluren with human liver microsomes indicated that the major metabolic pathway for ataluren is via direct glucuronidation and that the drug is not metabolized via cytochrome P450 (CYP). Glucuronidation was also observed in the incubation in human intestinal and kidney microsomes, but not in human pulmonary microsomes. UGT1A9 was found to be the major uridine diphosphate glucuronosyltransferase (UGT) responsible for ataluren glucuronidation in the liver and kidney microsomes. Enzyme kinetic analysis of the formation of ataluren acyl glucuronide, performed in human liver, kidney, and intestinal microsomes and recombinant human UGT1A9, found that increasing bovine serum albumin (BSA) levels enhanced the glucuronidation Michaelis‐Menten constant (Km) and ataluren protein binding but had a minimal effect on maximum velocity (Vmax) of glucuronidation. Due to the decreased unbound Michaelis‐Menten constant (Km,u), the ataluren unbound intrinsic clearance (CLint,u) increased for all experimental systems and BSA concentrations. Human kidney microsomes were about 3.7‐fold more active than human liver microsomes, in terms of CLint,u/mg protein, indicating that the kidney is also a key organ for the metabolism and disposition of ataluren in humans. Ataluren showed no or little potential to inhibit or induce most of the CYP enzymes.
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Affiliation(s)
- Ronald Kong
- PTC Therapeutics, Inc., South Plainfield, NJ, USA
| | - Jiyuan Ma
- PTC Therapeutics, Inc., South Plainfield, NJ, USA
| | | | | | | | | | | | | | - John Babiak
- PTC Therapeutics, Inc., South Plainfield, NJ, USA
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29
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Luna S, Torices L, Mingo J, Amo L, Rodríguez-Escudero I, Ruiz-Ibarlucea P, Erramuzpe A, Cortés JM, Tejada MI, Molina M, Nunes-Xavier CE, López JI, Cid VJ, Pulido R. A global analysis of the reconstitution of PTEN function by translational readthrough of PTEN pathogenic premature termination codons. Hum Mutat 2021; 42:551-566. [PMID: 33600059 DOI: 10.1002/humu.24186] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/15/2021] [Accepted: 02/14/2021] [Indexed: 12/29/2022]
Abstract
The PTEN tumor suppressor gene is mutated with high incidence in tumors and in the germline of patients with cancer predisposition or with macrocephaly associated with autism. PTEN nonsense mutations generating premature termination codons (PTC) and producing nonfunctional truncated PTEN proteins are frequent in association with human disease. However, there are no studies addressing the restoration of full-length PTEN proteins from the PTC-mutated PTEN gene by translational readthrough. Here, we have performed a global translational and functional readthrough analysis of the complete collection of PTEN PTC somatic or hereditary mutations found in tumors or in the germline of patients (disease-associated PTEN PTCome), and we set standards for the analysis of the potential of readthrough functional reconstitution in disease-relevant genes. Our analysis indicates that prevalent pathogenic PTEN PTC mutations are susceptible to PTEN functional restoration in response to readthrough-inducing compounds. Comprehensive readthrough analyses of disease-associated PTComes will be valuable tools for the implementation of readthrough-based precision interventions in specific groups of patients.
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Affiliation(s)
- Sandra Luna
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Leire Torices
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Janire Mingo
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Laura Amo
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Isabel Rodríguez-Escudero
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, UCM & Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Madrid, Spain
| | | | - Asier Erramuzpe
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - Jesús M Cortés
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.,Ikerbasque, The Basque Foundation for Science, Bilbao, Spain
| | - María I Tejada
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain
| | - María Molina
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, UCM & Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Madrid, Spain
| | - Caroline E Nunes-Xavier
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.,Institute for Cancer Research, Oslo University Hospital, Oslo, Norway
| | - José I López
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.,Department of Pathology, Cruces University Hospital, Barakaldo, Spain
| | - Víctor J Cid
- Departamento de Microbiología y Parasitología, Facultad de Farmacia, UCM & Instituto Ramón y Cajal de Investigaciones Sanitarias (IRYCIS), Madrid, Spain
| | - Rafael Pulido
- Biocruces Bizkaia Health Research Institute, Barakaldo, Spain.,Ikerbasque, The Basque Foundation for Science, Bilbao, Spain
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30
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Lidberg KA, Annalora AJ, Jozic M, Elson DJ, Wang L, Bammler TK, Ramm S, Monteiro MB, Himmelfarb J, Marcus CB, Iversen PL, Kelly EJ. Antisense oligonucleotide development for the selective modulation of CYP3A5 in renal disease. Sci Rep 2021; 11:4722. [PMID: 33633318 PMCID: PMC7907328 DOI: 10.1038/s41598-021-84194-w] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 02/10/2021] [Indexed: 11/09/2022] Open
Abstract
CYP3A5 is the primary CYP3A subfamily enzyme expressed in the human kidney and its aberrant expression may contribute to a broad spectrum of renal disorders. Pharmacogenetic studies have reported inconsistent linkages between CYP3A5 expression and hypertension, however, most investigators have considered CYP3A5*1 as active and CYP3A5*3 as an inactive allele. Observations of gender specific differences in CYP3A5*3/*3 protein expression suggest additional complexity in gene regulation that may underpin an environmentally responsive role for CYP3A5 in renal function. Reconciliation of the molecular mechanism driving conditional restoration of functional CYP3A5*3 expression from alternatively spliced transcripts, and validation of a morpholino-based approach for selectively suppressing renal CYP3A5 expression, is the focus of this work. Morpholinos targeting a cryptic splice acceptor created by the CYP3A5*3 mutation in intron 3 rescued functional CYP3A5 expression in vitro, and salt-sensitive cellular mechanisms regulating splicing and conditional expression of CYP3A5*3 transcripts are reported. The potential for a G-quadruplex (G4) in intron 3 to mediate restored splicing to exon 4 in CYP3A5*3 transcripts was also investigated. Finally, a proximal tubule microphysiological system (PT-MPS) was used to evaluate the safety profile of morpholinos in proximal tubule epithelial cells, highlighting their potential as a therapeutic platform for the treatment of renal disease.
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Affiliation(s)
- Kevin A Lidberg
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA
| | - Andrew J Annalora
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR, USA.
| | - Marija Jozic
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR, USA
| | - Daniel J Elson
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR, USA
| | - Lu Wang
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Theo K Bammler
- Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, WA, USA
| | - Susanne Ramm
- Victorian Centre for Functional Genomics, Peter MacCallum Cancer Centre, Melbourne, Australia
| | - Maria Beatriz Monteiro
- Depto Clinica Medica, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, São Paulo, Brazil
| | | | - Craig B Marcus
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR, USA
| | - Patrick L Iversen
- Department of Environmental and Molecular Toxicology, Oregon State University, Corvallis, OR, USA
| | - Edward J Kelly
- Department of Pharmaceutics, University of Washington, Seattle, WA, USA.
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31
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Hanson B, Wood MJA, Roberts TC. Molecular correction of Duchenne muscular dystrophy by splice modulation and gene editing. RNA Biol 2021; 18:1048-1062. [PMID: 33472516 DOI: 10.1080/15476286.2021.1874161] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Duchenne muscular dystrophy (DMD) is a currently incurable X-linked neuromuscular disorder, characterized by progressive muscle wasting and premature death, typically as a consequence of cardiac failure. DMD-causing mutations in the dystrophin gene are highly diverse, meaning that the development of a universally-applicable therapy to treat all patients is very challenging. The leading therapeutic strategy for DMD is antisense oligonucleotide-mediated splice modulation, whereby one or more specific exons are excluded from the mature dystrophin mRNA in order to correct the translation reading frame. Indeed, three exon skipping oligonucleotides have received FDA approval for use in DMD patients. Second-generation exon skipping drugs (i.e. peptide-antisense oligonucleotide conjugates) exhibit enhanced potency, and also induce dystrophin restoration in the heart. Similarly, multiple additional antisense oligonucleotide drugs targeting various exons are in clinical development in order to treat a greater proportion of DMD patient mutations. Relatively recent advances in the field of genome engineering (specifically, the development of the CRISPR/Cas system) have provided multiple promising therapeutic approaches for the RNA-directed genetic correction of DMD, including exon excision, exon reframing via the introduction of insertion/deletion mutations, disruption of splice signals to promote exon skipping, and the templated correction of point mutations by seamless homology directed repair or base editing technology. Potential limitations to the clinical translation of the splice modulation and gene editing approaches are discussed, including drug delivery, the importance of uniform dystrophin expression in corrected myofibres, safety issues (e.g. renal toxicity, viral vector immunogenicity, and off-target gene editing), and the high cost of therapy.
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Affiliation(s)
- Britt Hanson
- Department of Paediatrics, University of Oxford, Oxford, UK.,Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK
| | - Matthew J A Wood
- Department of Paediatrics, University of Oxford, Oxford, UK.,MDUK Oxford Neuromuscular Centre, Oxford, UK
| | - Thomas C Roberts
- Department of Paediatrics, University of Oxford, Oxford, UK.,MDUK Oxford Neuromuscular Centre, Oxford, UK
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32
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Formulation and Stability of Ataluren Eye Drop Oily Solution for Aniridia. Pharmaceutics 2020; 13:pharmaceutics13010007. [PMID: 33375041 PMCID: PMC7822034 DOI: 10.3390/pharmaceutics13010007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/17/2020] [Accepted: 12/17/2020] [Indexed: 12/15/2022] Open
Abstract
Congenital aniridia is a rare and severe panocular disease characterized by a complete or partial iris defect clinically detectable at birth. The most common form of aniridia occurring in around 90% of cases is caused by PAX6 haploinsufficiency. The phenotype includes ptosis, nystagmus, corneal limbal insufficiency, glaucoma, cataract, optic nerve, and foveal hypoplasia. Ataluren eye drops aim to restore ocular surface PAX6 haploinsufficiency in aniridia-related keratopathy (ARK). However, there are currently no available forms of the ophthalmic solution. The objective of this study was to assess the physicochemical and microbiological stability of ataluren 1% eye drop in preservative-free low-density polyethylene (LDPE) bottle with an innovative insert that maintains sterility after opening. Because ataluren is a strongly lipophilic compound, the formulation is complex and involves a strategy based on co-solvents in an aqueous phase or an oily formulation capable of totally dissolving the active ingredient. The visual aspect, ataluren quantification by a stability-indicating chromatographic method, and microbiological sterility were analyzed. The oily formulation in castor oil and DMSO (10%) better protects ataluren hydrolysis and oxidative degradation and permits its complete solubilization. Throughout the 60 days period, the oily solution in the LDPE bottle remained clear without any precipitation or color modification, and no drug loss and no microbial development were detected. The demonstrated physical and microbiological stability of ataluren 1% eye drop formulation at 22–25 °C might facilitate clinical research in aniridia.
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33
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Poly(A)-Binding Protein Regulates the Efficiency of Translation Termination. Cell Rep 2020; 33:108399. [PMID: 33207198 DOI: 10.1016/j.celrep.2020.108399] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Revised: 09/01/2020] [Accepted: 10/27/2020] [Indexed: 11/21/2022] Open
Abstract
Multiple factors influence translation termination efficiency, including nonsense codon identity and immediate context. To determine whether the relative position of a nonsense codon within an open reading frame (ORF) influences termination efficiency, we quantitate the production of prematurely terminated and/or readthrough polypeptides from 26 nonsense alleles of 3 genes expressed in yeast. The accumulation of premature termination products and the extent of readthrough for the respective premature termination codons (PTCs) manifest a marked dependence on PTC proximity to the mRNA 3' end. Premature termination products increase in relative abundance, whereas readthrough efficiencies decrease progressively across different ORFs, and readthrough efficiencies for a PTC increase in response to 3' UTR lengthening. These effects are eliminated and overall translation termination efficiency decreases considerably in cells harboring pab1 mutations. Our results support a critical role for poly(A)-binding protein in the regulation of translation termination and also suggest that inefficient termination is a trigger for nonsense-mediated mRNA decay (NMD).
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34
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LC-MS/MS quantification of ataluren and ataluren acyl glucuronide in human plasma/urine: application in clinical studies. Bioanalysis 2020; 12:1545-1555. [PMID: 33064028 DOI: 10.4155/bio-2020-0214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background: This paper describes for the first-time analytical procedures established to resolve the challenges associated with simultaneous and direct quantification of ataluren and ataluren-O-1β-acyl glucuronide (AAG) by LC-MS/MS in human plasma and urine matrices. Methodology/results: The plasma quantification method was validated for calibration range of 12.5-12500 ng/ml for ataluren and 6.25-2500 ng/ml for AAG. The urine quantification method was validated for calibration range of 0.01-10 and 1-1000 μg/ml for ataluren and AAG, respectively. Plasma and urine samples were stabilized upon collection and through storage to prevent hydrolysis and acyl migration of AAG. Conclusion: Methods described in this paper enabled successful completion of ataluren clinical pharmacology studies for simultaneous pharmacokinetic assessment of ataluren and AAG.
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35
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Campbell C, Barohn RJ, Bertini E, Chabrol B, Comi GP, Darras BT, Finkel RS, Flanigan KM, Goemans N, Iannaccone ST, Jones KJ, Kirschner J, Mah JK, Mathews KD, McDonald CM, Mercuri E, Nevo Y, Péréon Y, Renfroe JB, Ryan MM, Sampson JB, Schara U, Sejersen T, Selby K, Tulinius M, Vílchez JJ, Voit T, Wei LJ, Wong BL, Elfring G, Souza M, McIntosh J, Trifillis P, Peltz SW, Muntoni F. Meta-analyses of ataluren randomized controlled trials in nonsense mutation Duchenne muscular dystrophy. J Comp Eff Res 2020; 9:973-984. [DOI: 10.2217/cer-2020-0095] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: Assess the totality of efficacy evidence for ataluren in patients with nonsense mutation Duchenne muscular dystrophy (nmDMD). Materials & methods: Data from the two completed randomized controlled trials (ClinicalTrials.gov: NCT00592553; NCT01826487) of ataluren in nmDMD were combined to examine the intent-to-treat (ITT) populations and two patient subgroups (baseline 6-min walk distance [6MWD] ≥300–<400 or <400 m). Meta-analyses examined 6MWD change from baseline to week 48. Results: Statistically significant differences in 6MWD change with ataluren versus placebo were observed across all three meta-analyses. Least-squares mean difference (95% CI): ITT (n = 342), +17.2 (0.2–34.1) m, p = 0.0473; ≥300–<400 m (n = 143), +43.9 (18.2–69.6) m, p = 0.0008; <400 m (n = 216), +27.7 (6.4–49.0) m, p = 0.0109. Conclusion: These meta-analyses support previous evidence for ataluren in slowing disease progression versus placebo in patients with nmDMD over 48 weeks. Treatment benefit was most evident in patients with a baseline 6MWD ≥300–<400 m (the ambulatory transition phase), thereby informing future trial design.
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Affiliation(s)
- Craig Campbell
- Schulich School of Medicine & Dentistry, Western University, London, ON, N6A 5C1, Canada
| | | | - Enrico Bertini
- Bambino Gesù Children’s Research Hospital, Rome, 00146, Italy
| | - Brigitte Chabrol
- Hôpital de la Timone, Unité de Médecine Infantile, Marseille, 13385, France
| | - Giacomo Pietro Comi
- IRCCS Fondazione Ca'Granda Ospedale Maggiore Policlinico, Dino Ferrari Centre, Department of Pathophysiology & Transplantation, University of Milan, Milan, 20122, Italy
| | - Basil T Darras
- Boston Children’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Richard S Finkel
- Children’s Hospital of Philadelphia, Philadelphia, PA 19104, USA
- St. Jude Children’s Research Hospital, Memphis, TN 38105, USA
| | | | | | | | - Kristi J Jones
- Kids Neuroscience, The Children’s Hospital at Westmead, Westmead, NSW, 2145, Australia
| | - Janbernd Kirschner
- Department of Neuropediatrics & Muscle Disorders, Medical Center, University of Freiburg, Freiburg 79110, Germany
| | - Jean K Mah
- Department of Pediatrics, Division of Pediatric Neurology, Alberta Children’s Hospital, University of Calgary, Calgary, AB T3B 6A8, Canada
| | - Katherine D Mathews
- Departments of Pediatrics & Neurology, Division of Pediatric Neurology, University of Iowa Carver College of Medicine, Iowa City, IA 52242, USA
| | - Craig M McDonald
- University of California Davis Health, Sacramento, CA 95817, USA
| | - Eugenio Mercuri
- Department of Pediatric Neurology, Catholic University, Rome, 00168, Italy
| | - Yoram Nevo
- Schneider Children’s Medical Center, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Yann Péréon
- Reference Centre for Neuromuscular Disorders AOC, Hôtel-Dieu, Nantes, 44000, France
| | - J Ben Renfroe
- Child Neurology Center of Northwest Florida, Gulf Breeze, FL 32561, USA
| | - Monique M Ryan
- The Royal Children’s Hospital, Parkville, Victoria, 3052, Australia
| | - Jacinda B Sampson
- Stanford University Medical Center, Department of Neurology & Neurological Sciences, Stanford, CA 94305, USA
| | - Ulrike Schara
- Department of Pediatric Neurology, University Hospital Essen, University of Duisburg-Essen, Essen, 45122, Germany
| | - Thomas Sejersen
- Karolinska University Hospital, Karolinska Institutet, Stockholm, 171 76, Sweden
| | - Kathryn Selby
- Division of Neurology, British Columbia Children’s Hospital, Vancouver, BC, V6H 3N1, Canada
| | - Már Tulinius
- Gothenburg University, Queen Silvia Children’s Hospital, Gothenburg, 416 85, Sweden
| | - Juan J Vílchez
- Hospital Universitario y Politécnico La Fe, CIBERER, Valencia, 46026, Spain
| | - Thomas Voit
- NIHR Great Ormond Street Hospital Biomedical Research Centre, University College London & UCL Great Ormond Street Institute of Child Health, Great Ormond Street Hospital Trust, London, WC1N 1EH, UK
| | - Lee-Jen Wei
- Harvard TH Chan School of Public Health, Harvard University, Boston, MA 02115, USA
| | - Brenda L Wong
- University of Massachusetts Medical School, UMass, Worcester, MA 01655, USA
| | - Gary Elfring
- PTC Therapeutics Inc., South Plainfield, NJ 07080, USA
| | - Marcio Souza
- PTC Therapeutics Inc., South Plainfield, NJ 07080, USA
| | | | | | | | - Francesco Muntoni
- NIHR Great Ormond Street Hospital Biomedical Research Centre, University College London & UCL Great Ormond Street Institute of Child Health, Great Ormond Street Hospital Trust, London, WC1N 1EH, UK
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36
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Pibiri I, Melfi R, Tutone M, Di Leonardo A, Pace A, Lentini L. Targeting Nonsense: Optimization of 1,2,4-Oxadiazole TRIDs to Rescue CFTR Expression and Functionality in Cystic Fibrosis Cell Model Systems. Int J Mol Sci 2020; 21:ijms21176420. [PMID: 32899265 PMCID: PMC7504161 DOI: 10.3390/ijms21176420] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/26/2020] [Accepted: 09/01/2020] [Indexed: 02/07/2023] Open
Abstract
Cystic fibrosis (CF) patients develop a severe form of the disease when the cystic fibrosis transmembrane conductance regulator (CFTR) gene is affected by nonsense mutations. Nonsense mutations are responsible for the presence of a premature termination codon (PTC) in the mRNA, creating a lack of functional protein. In this context, translational readthrough-inducing drugs (TRIDs) represent a promising approach to correct the basic defect caused by PTCs. By using computational optimization and biological screening, we identified three new small molecules showing high readthrough activity. The activity of these compounds has been verified by evaluating CFTR expression and functionality after treatment with the selected molecules in cells expressing nonsense–CFTR–mRNA. Additionally, the channel functionality was measured by the halide sensitive yellow fluorescent protein (YFP) quenching assay. All three of the new TRIDs displayed high readthrough activity and low toxicity and can be considered for further evaluation as a therapeutic approach toward the second major cause of CF.
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Affiliation(s)
- Ivana Pibiri
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università degli Studi di Palermo, Viale delle Scienze Ed. 16-17, 90128 Palermo, Italy; (R.M.); (M.T.); (A.D.L.); (A.P.)
- Correspondence: (I.P.); (L.L.); Tel.: +39-091-238-97545 (I.P.); +39-091-238-97341 (L.L.)
| | - Raffaella Melfi
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università degli Studi di Palermo, Viale delle Scienze Ed. 16-17, 90128 Palermo, Italy; (R.M.); (M.T.); (A.D.L.); (A.P.)
| | - Marco Tutone
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università degli Studi di Palermo, Viale delle Scienze Ed. 16-17, 90128 Palermo, Italy; (R.M.); (M.T.); (A.D.L.); (A.P.)
| | - Aldo Di Leonardo
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università degli Studi di Palermo, Viale delle Scienze Ed. 16-17, 90128 Palermo, Italy; (R.M.); (M.T.); (A.D.L.); (A.P.)
- Centro di OncoBiologia Sperimentale (COBS), via San Lorenzo Colli, 90145 Palermo, Italy
| | - Andrea Pace
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università degli Studi di Palermo, Viale delle Scienze Ed. 16-17, 90128 Palermo, Italy; (R.M.); (M.T.); (A.D.L.); (A.P.)
| | - Laura Lentini
- Dipartimento di Scienze e Tecnologie Biologiche, Chimiche e Farmaceutiche (STEBICEF), Università degli Studi di Palermo, Viale delle Scienze Ed. 16-17, 90128 Palermo, Italy; (R.M.); (M.T.); (A.D.L.); (A.P.)
- Correspondence: (I.P.); (L.L.); Tel.: +39-091-238-97545 (I.P.); +39-091-238-97341 (L.L.)
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Adachi H, Yu YT. Pseudouridine-mediated stop codon readthrough in S. cerevisiae is sequence context-independent. RNA (NEW YORK, N.Y.) 2020; 26:1247-1256. [PMID: 32434780 PMCID: PMC7430670 DOI: 10.1261/rna.076042.120] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2020] [Accepted: 05/19/2020] [Indexed: 05/26/2023]
Abstract
We have previously shown that when the uridine of a stop codon (UAA, UAG, or UGA) is pseudouridylated, the ribosome reads through the modified stop codon. However, it is not clear as to whether or not the pseudouridine (Ψ)-mediated readthrough is dependent on the sequence context of mRNA. Here, we use several different approaches and the yeast system to address this question. We show that when a stop codon (premature termination codon, PTC) is introduced into the coding region of a reporter mRNA at several different positions (with different sequence contexts) and pseudouridylated, we detect similar levels of readthrough. Using mutational and selection/screen analyses, we also show that the upstream sequence (relative to PTC) as well as the nucleotides surrounding the PTC (upstream and downstream) play a minimal role (if at all) in Ψ-mediated ribosome readthrough. Interestingly, we detect no suppression of NMD (nonsense-mediated mRNA decay) by targeted PTC pseudouridylation in the yeast system. Our results indicate that Ψ-mediated nonsense suppression occurs at the translational level, and that the suppression is sequence context-independent, unlike some previously characterized rare stop codon readthrough events.
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Affiliation(s)
- Hironori Adachi
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, Rochester, New York 14642, USA
| | - Yi-Tao Yu
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, Rochester, New York 14642, USA
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Konstan MW, VanDevanter DR, Rowe SM, Wilschanski M, Kerem E, Sermet-Gaudelus I, DiMango E, Melotti P, McIntosh J, De Boeck K. Efficacy and safety of ataluren in patients with nonsense-mutation cystic fibrosis not receiving chronic inhaled aminoglycosides: The international, randomized, double-blind, placebo-controlled Ataluren Confirmatory Trial in Cystic Fibrosis (ACT CF). J Cyst Fibros 2020; 19:595-601. [PMID: 31983658 PMCID: PMC9167581 DOI: 10.1016/j.jcf.2020.01.007] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 01/17/2020] [Indexed: 12/18/2022]
Abstract
BACKGROUND Ataluren was developed for potential treatment of nonsense-mutation cystic fibrosis (CF). A previous phase 3 ataluren study failed to meet its primary efficacy endpoint, but post-hoc analyses suggested that aminoglycosides may have interfered with ataluren's action. Thus, this subsequent trial (NCT02139306) was designed to assess the efficacy and safety of ataluren in patients with nonsense-mutation CF not receiving aminoglycosides. METHODS Eligible subjects with nonsense-mutation CF (aged ≥6 years; percent predicted (pp) FEV1 ≥40 and ≤90) from 75 sites in 16 countries were randomly assigned in double-blinded fashion to receive oral ataluren or matching placebo thrice daily for 48 weeks. The primary endpoint was absolute change in average ppFEV1 from baseline to the average of Weeks 40 and 48. FINDINGS 279 subjects were enrolled; 138 subjects in the ataluren arm and 136 in the placebo arm were evaluable for efficacy. Absolute ppFEV1 change from baseline did not differ significantly between the ataluren and placebo groups at Week 40 (-0.8 vs -1.8) or Week 48 (-1.7 vs -2.4). Average ppFEV1 treatment difference from baseline to Weeks 40 and 48 was 0.6 (95% CI -1.3, 2.5; p = 0.54). Pulmonary exacerbation rate per 48 weeks was not significantly different (ataluren 0.95 vs placebo 1.13; rate ratio p = 0.40). Safety was similar between groups. No life-threatening adverse events or deaths were reported. INTERPRETATION Neither ppFEV1 change nor pulmonary exacerbation rate over 48 weeks were statistically different between ataluren and placebo groups. Development of a nonsense-mutation CF therapy remains elusive.
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Affiliation(s)
- M W Konstan
- Rainbow Babies and Children's Hospital, Cleveland, OH 44106 USA; Case Western Reserve University School of Medicine, Cleveland, OH 44106 USA.
| | - D R VanDevanter
- Case Western Reserve University School of Medicine, Cleveland, OH 44106 USA
| | - S M Rowe
- Pulmonary and Critical Care Medicine, University of Alabama at Birmingham, Birmingham, AL 35249 USA
| | - M Wilschanski
- Center for Cystic Fibrosis, Hadassah Hebrew University Medical Center, Jerusalem, 91240, Israel
| | - E Kerem
- Center for Cystic Fibrosis, Hadassah Hebrew University Medical Center, Jerusalem, 91240, Israel
| | - I Sermet-Gaudelus
- Centre de Ressource et de Competence de la Mucoviscidose, Service de Pediatrie Generale, Service de Pneumologie Pediatrique, Service de Radiologie Pediatrique, Centre d'Investigation Clinique Hôpital Necker - Enfants Malades, 75015 Paris, France
| | - E DiMango
- Pulmonary, Allergy, and Critical Care Medicine, Columbia University, Department of Medicine, New York, NY 10032 USA
| | - P Melotti
- Centro Fibrosi Cistica, Azienda Ospedaliera Universitaria Integrata, Verona, Italy
| | - J McIntosh
- PTC Therapeutics, South Plainfield, NJ 07080 USA
| | - K De Boeck
- Pediatric Pulmonology and Infectious Diseases, University Hospital of Leuven, University of Leuven, Belgium
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Nonsense Suppression Therapy: New Hypothesis for the Treatment of Inherited Bone Marrow Failure Syndromes. Int J Mol Sci 2020; 21:ijms21134672. [PMID: 32630050 PMCID: PMC7369780 DOI: 10.3390/ijms21134672] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Revised: 06/29/2020] [Accepted: 06/29/2020] [Indexed: 12/13/2022] Open
Abstract
Inherited bone marrow failure syndromes (IBMFS) are a group of cancer-prone genetic diseases characterized by hypocellular bone marrow with impairment in one or more hematopoietic lineages. The pathogenesis of IBMFS involves mutations in several genes which encode for proteins involved in DNA repair, telomere biology and ribosome biogenesis. The classical IBMFS include Shwachman–Diamond syndrome (SDS), Diamond–Blackfan anemia (DBA), Fanconi anemia (FA), dyskeratosis congenita (DC), and severe congenital neutropenia (SCN). IBMFS are associated with high risk of myelodysplastic syndrome (MDS), acute myeloid leukemia (AML), and solid tumors. Unfortunately, no specific pharmacological therapies have been highly effective for IBMFS. Hematopoietic stem cell transplantation provides a cure for aplastic or myeloid neoplastic complications. However, it does not affect the risk of solid tumors. Since approximately 28% of FA, 24% of SCN, 21% of DBA, 20% of SDS, and 17% of DC patients harbor nonsense mutations in the respective IBMFS-related genes, we discuss the use of the nonsense suppression therapy in these diseases. We recently described the beneficial effect of ataluren, a nonsense suppressor drug, in SDS bone marrow hematopoietic cells ex vivo. A similar approach could be therefore designed for treating other IBMFS. In this review we explain in detail the new generation of nonsense suppressor molecules and their mechanistic roles. Furthermore, we will discuss strengths and limitations of these molecules which are emerging from preclinical and clinical studies. Finally we discuss the state-of-the-art of preclinical and clinical therapeutic studies carried out for IBMFS.
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Morais P, Adachi H, Yu YT. Suppression of Nonsense Mutations by New Emerging Technologies. Int J Mol Sci 2020; 21:ijms21124394. [PMID: 32575694 PMCID: PMC7352488 DOI: 10.3390/ijms21124394] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Revised: 06/17/2020] [Accepted: 06/18/2020] [Indexed: 12/18/2022] Open
Abstract
Nonsense mutations often result from single nucleotide substitutions that change a sense codon (coding for an amino acid) to a nonsense or premature termination codon (PTC) within the coding region of a gene. The impact of nonsense mutations is two-fold: (1) the PTC-containing mRNA is degraded by a surveillance pathway called nonsense-mediated mRNA decay (NMD) and (2) protein translation stops prematurely at the PTC codon, and thus no functional full-length protein is produced. As such, nonsense mutations result in a large number of human diseases. Nonsense suppression is a strategy that aims to correct the defects of hundreds of genetic disorders and reverse disease phenotypes and conditions. While most clinical trials have been performed with small molecules, there is an increasing need for sequence-specific repair approaches that are safer and adaptable to personalized medicine. Here, we discuss recent advances in both conventional strategies as well as new technologies. Several of these will soon be tested in clinical trials as nonsense therapies, even if they still have some limitations and challenges to overcome.
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Affiliation(s)
- Pedro Morais
- ProQR Therapeutics, Zernikedreef 9, 2333 CK Leiden, The Netherlands;
| | - Hironori Adachi
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA;
| | - Yi-Tao Yu
- Department of Biochemistry and Biophysics, Center for RNA Biology, University of Rochester Medical Center, 601 Elmwood Avenue, Rochester, NY 14642, USA;
- Correspondence: ; Tel.: +1-(585)-275-1271; Fax: +1-(585)-275-6007
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Leier A, Bedwell DM, Chen AT, Dickson G, Keeling KM, Kesterson RA, Korf BR, Marquez Lago TT, Müller UF, Popplewell L, Zhou J, Wallis D. Mutation-Directed Therapeutics for Neurofibromatosis Type I. MOLECULAR THERAPY. NUCLEIC ACIDS 2020; 20:739-753. [PMID: 32408052 PMCID: PMC7225739 DOI: 10.1016/j.omtn.2020.04.012] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/20/2020] [Accepted: 04/23/2020] [Indexed: 02/07/2023]
Abstract
Significant advances in biotechnology have led to the development of a number of different mutation-directed therapies. Some of these techniques have matured to a level that has allowed testing in clinical trials, but few have made it to approval by drug-regulatory bodies for the treatment of specific diseases. While there are still various hurdles to be overcome, recent success stories have proven the potential power of mutation-directed therapies and have fueled the hope of finding therapeutics for other genetic disorders. In this review, we summarize the state-of-the-art of various therapeutic approaches and assess their applicability to the genetic disorder neurofibromatosis type I (NF1). NF1 is caused by the loss of function of neurofibromin, a tumor suppressor and downregulator of the Ras signaling pathway. The condition is characterized by a variety of phenotypes and includes symptoms such as skin spots, nervous system tumors, skeletal dysplasia, and others. Hence, depending on the patient, therapeutics may need to target different tissues and cell types. While we also discuss the delivery of therapeutics, in particular via viral vectors and nanoparticles, our main focus is on therapeutic techniques that reconstitute functional neurofibromin, most notably cDNA replacement, CRISPR-based DNA repair, RNA repair, antisense oligonucleotide therapeutics including exon skipping, and nonsense suppression.
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Affiliation(s)
- Andre Leier
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - David M Bedwell
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Ann T Chen
- Department of Neurosurgery, Yale University, New Haven, CT 06510, USA
| | - George Dickson
- Centre of Biomedical Sciences, Department of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK
| | - Kim M Keeling
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Robert A Kesterson
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | - Bruce R Korf
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA
| | | | - Ulrich F Müller
- Department of Chemistry and Biochemistry, University of California San Diego, La Jolla, CA 92093, USA
| | - Linda Popplewell
- Centre of Biomedical Sciences, Department of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK
| | - Jiangbing Zhou
- Department of Neurosurgery, Yale University, New Haven, CT 06510, USA
| | - Deeann Wallis
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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Wang X, Shan X, Gregory-Evans K, Gregory-Evans CY. RNA-based therapies in animal models of Leber congenital amaurosis causing blindness. PRECISION CLINICAL MEDICINE 2020; 3:113-126. [PMID: 35692607 PMCID: PMC8985810 DOI: 10.1093/pcmedi/pbaa009] [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: 01/13/2020] [Revised: 03/05/2020] [Accepted: 03/10/2020] [Indexed: 11/14/2022] Open
Abstract
Abstract
Leber congenital amaurosis (LCA) is a severe, genetically heterogeneous recessive eye disease in which ~ 35% of gene mutations are in-frame nonsense mutations coding for loss-of-function premature termination codons (PTCs) in mRNA. Nonsense suppression therapy allows read-through of PTCs leading to production of full-length protein. A limitation of nonsense suppression is that nonsense-mediated decay (NMD) degrades PTC-containing RNA transcripts. The purpose of this study was to determine whether inhibition of NMD could improve nonsense suppression efficacy in vivo. Using a high-throughput approach in the recessive cep290 zebrafish model of LCA (cep290;Q1223X), we first tested the NMD inhibitor Amlexanox in combination with the nonsense suppression drug Ataluren. We observed reduced retinal cell death and improved visual function. With these positive data, we next investigated whether this strategy was also applicable across species in two mammalian models: Rd12 (rpe65;R44X) and Rd3 (rd3;R107X) mouse models of LCA. In the Rd12 model, cell death was reduced, RPE65 protein was produced, and in vivo visual function testing was improved. We establish for the first time that the mechanism of action of Amlexanox in Rd12 retina was through reduced UPF1 phosphorylation. In the Rd3 model, however, no beneficial effect was observed with Ataluren alone or in combination with Amlexanox. This variation in response establishes that some forms of nonsense mutation LCA can be targeted by RNA therapies, but that this needs to be verified for each genotype. The implementation of precision medicine by identifying better responders to specific drugs is essential for development of validated retinal therapies.
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Affiliation(s)
- Xia Wang
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver BC V5Z 3N9, Canada
| | - Xianghong Shan
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver BC V5Z 3N9, Canada
| | - Kevin Gregory-Evans
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver BC V5Z 3N9, Canada
| | - Cheryl Y Gregory-Evans
- Department of Ophthalmology and Visual Sciences, University of British Columbia, Vancouver BC V5Z 3N9, Canada
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Nonsense-Mediated mRNA Decay: Pathologies and the Potential for Novel Therapeutics. Cancers (Basel) 2020; 12:cancers12030765. [PMID: 32213869 PMCID: PMC7140085 DOI: 10.3390/cancers12030765] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/19/2020] [Accepted: 03/19/2020] [Indexed: 12/22/2022] Open
Abstract
Nonsense-mediated messenger RNA (mRNA) decay (NMD) is a surveillance pathway used by cells to control the quality mRNAs and to fine-tune transcript abundance. NMD plays an important role in cell cycle regulation, cell viability, DNA damage response, while also serving as a barrier to virus infection. Disturbance of this control mechanism caused by genetic mutations or dys-regulation of the NMD pathway can lead to pathologies, including neurological disorders, immune diseases and cancers. The role of NMD in cancer development is complex, acting as both a promoter and a barrier to tumour progression. Cancer cells can exploit NMD for the downregulation of key tumour suppressor genes, or tumours adjust NMD activity to adapt to an aggressive immune microenvironment. The latter case might provide an avenue for therapeutic intervention as NMD inhibition has been shown to lead to the production of neoantigens that stimulate an immune system attack on tumours. For this reason, understanding the biology and co-option pathways of NMD is important for the development of novel therapeutic agents. Inhibitors, whose design can make use of the many structures available for NMD study, will play a crucial role in characterizing and providing diverse therapeutic options for this pathway in cancer and other diseases.
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Liu X, Zhang Y, Zhang B, Gao H, Qiu C. Nonsense suppression induced readthrough of a novel PAX6 mutation in patient-derived cells of congenital aniridia. Mol Genet Genomic Med 2020; 8:e1198. [PMID: 32125788 PMCID: PMC7216799 DOI: 10.1002/mgg3.1198] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 02/07/2020] [Accepted: 02/14/2020] [Indexed: 12/11/2022] Open
Abstract
Background Congenital aniridia is a severe ocular abnormality characterized by incomplete formation of the iris and many other ocular complications. Most cases are caused by the paired box 6 (PAX6) gene mutations generating premature termination codons (PTCs). Methods Ophthalmic examination was performed on a Chinese pedigree with congenital aniridia. The mutation was identified by targeted next‐generation sequencing. Nonsense suppression therapy was applied on patient‐derived lymphocytes. The PAX6 expression was assayed by real‐time polymerase chain reaction and Western blot. Results Complete aniridia was complicated with horizontal nystagmus, contract, foveal hypoplasia, and microphthalmia. A novel heterozygous c.702_703delinsAT (p.Tyr234*) mutation was found in exon 9 of PAX6, generating a PTC at the homeodomain. There were about 50% reductions of both full‐length PAX6 protein and PAX6 mRNA in patient‐derived lymphocytes, indicating haploinsufficiency due to nonsense‐mediated mRNA decay. Ataluren (PTC124) and geneticin (G418) could induce about 30%–40% translational readthrough. Nonsense suppression therapy restored PAX6 protein to about 65%–70% of unaffected family controls. Conclusion Our data expanded the genetic and phenotypic variations of congenital aniridia, and showed the therapeutic effect of nonsense suppression on this disease using patient‐derived cells.
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Affiliation(s)
- Xiaoliang Liu
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Yuanyuan Zhang
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Bijun Zhang
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Haiming Gao
- Department of Clinical Genetics, Shengjing Hospital of China Medical University, Shenyang, China
| | - Chuang Qiu
- Department of Orthopaedics, Shengjing Hospital of China Medical University, Shenyang, China
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Srinivas M, Satyaveni S, Ram B. Design, Synthesis, and Biological Evaluation of 1,2,4-Oxadiazole-Isoxazole Linked Quinazoline Derivatives as Anticancer Agents. RUSS J GEN CHEM+ 2020. [DOI: 10.1134/s1070363219120260] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Mercuri E, Muntoni F, Osorio AN, Tulinius M, Buccella F, Morgenroth LP, Gordish-Dressman H, Jiang J, Trifillis P, Zhu J, Kristensen A, Santos CL, Henricson EK, McDonald CM, Desguerre I. Safety and effectiveness of ataluren: comparison of results from the STRIDE Registry and CINRG DMD Natural History Study. J Comp Eff Res 2020; 9:341-360. [PMID: 31997646 PMCID: PMC7610147 DOI: 10.2217/cer-2019-0171] [Citation(s) in RCA: 71] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Aim: Strategic Targeting of Registries and International Database of Excellence (STRIDE) is an ongoing, multicenter registry providing real-world evidence regarding ataluren use in patients with nonsense mutation Duchenne muscular dystrophy (nmDMD). We examined the effectiveness of ataluren + standard of care (SoC) in the registry versus SoC alone in the Cooperative International Neuromuscular Research Group (CINRG) Duchenne Natural History Study (DNHS), DMD genotype–phenotype/–ataluren benefit correlations and ataluren safety. Patients & methods: Propensity score matching was performed to identify STRIDE and CINRG DNHS patients who were comparable in established disease progression predictors (registry cut-off date, 9 July 2018). Results & conclusion: Kaplan–Meier analyses demonstrated that ataluren + SoC significantly delayed age at loss of ambulation and age at worsening performance in timed function tests versus SoC alone (p ≤ 0.05). There were no DMD genotype–phenotype/ataluren benefit correlations. Ataluren was well tolerated. These results indicate that ataluren + SoC delays functional milestones of DMD progression in patients with nmDMD in routine clinical practice. ClinicalTrials.gov identifier: NCT02369731. ClinicalTrials.gov identifier: NCT02369731.
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Affiliation(s)
- Eugenio Mercuri
- Department of Pediatric Neurology, Catholic University, Rome, Italy.,Centro Clinico Nemo, Policlinico Universitario A Gemelli IRCCS, Rome, Italy
| | - Francesco Muntoni
- Dubowitz Neuromuscular Centre & MRC Centre for Neuromuscular Diseases, University College London, Institute of Child Health & Great Ormond Street Hospital for Children Foundation Trust, 30 Guildford Street, London, WC1N 1EH, UK.,NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, Great Ormond Street Hospital Trust, London, UK
| | - Andrés Nascimento Osorio
- Hospital Sant Joan de Déu Unidad de Patología Neuromuscular, Universidad de Barcelona, CIBERER, ISCIII, Barcelona, Spain
| | - Már Tulinius
- Department of Pediatrics, Gothenburg University, Queen Silvia Children's Hospital, Gothenburg, Sweden
| | | | - Lauren P Morgenroth
- Therapeutic Research in Neuromuscular Disorders Solutions, Pittsburgh, PA, USA
| | - Heather Gordish-Dressman
- Center for Genetic Medicine, Children's National Health System & the George Washington, Washington, DC, USA
| | - Joel Jiang
- PTC Therapeutics Inc., South Plainfield, NJ 07080-2449, USA
| | | | - Jin Zhu
- PTC Therapeutics Inc., South Plainfield, NJ 07080-2449, USA
| | | | | | - Erik K Henricson
- University of California Davis School of Medicine, Davis, CA, USA
| | - Craig M McDonald
- University of California Davis School of Medicine, Davis, CA, USA
| | - Isabelle Desguerre
- APHP Necker - Enfants Malades Hospital, Paris V Descartes University, Neuromuscular Network FILNEMUS, Paris, France
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Screening Readthrough Compounds to Suppress Nonsense Mutations: Possible Application to β-Thalassemia. J Clin Med 2020; 9:jcm9020289. [PMID: 31972957 PMCID: PMC7073686 DOI: 10.3390/jcm9020289] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Revised: 01/08/2020] [Accepted: 01/13/2020] [Indexed: 02/07/2023] Open
Abstract
Several types of thalassemia (including β039-thalassemia) are caused by nonsense mutations in genes controlling globin production, leading to premature translation termination and mRNA destabilization mediated by the nonsense mediated mRNA decay. Drugs (for instance, aminoglycosides) can be designed to suppress premature translation termination by inducing readthrough (or nonsense suppression) at the premature termination codon. These findings have introduced new hopes for the development of a pharmacologic approach to cure this genetic disease. In the present review, we first summarize the principle and current status of the chemical relief for the expression of functional proteins from genes otherwise unfruitful for the presence of nonsense mutations. Second, we compare data available on readthrough molecules for β0-thalassemia. The examples reported in the review strongly suggest that ribosomal readthrough should be considered as a therapeutic approach for the treatment of β0-thalassemia caused by nonsense mutations. Concluding, the discovery of molecules, exhibiting the property of inducing β-globin, such as readthrough compounds, is of great interest and represents a hope for several patients, whose survival will depend on the possible use of drugs rendering blood transfusion and chelation therapy unnecessary.
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Ataluren for the Treatment of Usher Syndrome 2A Caused by Nonsense Mutations. Int J Mol Sci 2019; 20:ijms20246274. [PMID: 31842393 PMCID: PMC6940777 DOI: 10.3390/ijms20246274] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 12/05/2019] [Accepted: 12/10/2019] [Indexed: 12/18/2022] Open
Abstract
The identification of genetic defects that underlie inherited retinal diseases (IRDs) paves the way for the development of therapeutic strategies. Nonsense mutations caused approximately 12% of all IRD cases, resulting in a premature termination codon (PTC). Therefore, an approach that targets nonsense mutations could be a promising pharmacogenetic strategy for the treatment of IRDs. Small molecules (translational read-through inducing drugs; TRIDs) have the potential to mediate the read-through of nonsense mutations by inducing expression of the full-length protein. We provide novel data on the read-through efficacy of Ataluren on a nonsense mutation in the Usher syndrome gene USH2A that causes deaf-blindness in humans. We demonstrate Ataluren´s efficacy in both transiently USH2AG3142*-transfected HEK293T cells and patient-derived fibroblasts by restoring USH2A protein expression. Furthermore, we observed enhanced ciliogenesis in patient-derived fibroblasts after treatment with TRIDs, thereby restoring a phenotype that is similar to that found in healthy donors. In light of recent findings, we validated Ataluren´s efficacy to induce read-through on a nonsense mutation in USH2A-related IRD. In line with published data, our findings support the use of patient-derived fibroblasts as a platform for the validation of preclinical therapies. The excellent biocompatibility combined with sustained read-through efficacy makes Ataluren an ideal TRID for treating nonsense mutations based IRDs.
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Lommatzsch ST, Taylor-Cousar JL. The combination of tezacaftor and ivacaftor in the treatment of patients with cystic fibrosis: clinical evidence and future prospects in cystic fibrosis therapy. Ther Adv Respir Dis 2019; 13:1753466619844424. [PMID: 31027466 PMCID: PMC6487765 DOI: 10.1177/1753466619844424] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Years of tremendous study have dawned a new era for the treatment of cystic fibrosis (CF). For years CF care was rooted in the management of organ dysfunction resulting from the mal-effects of absent anion transport through the CF transmembrane regulator (CFTR) protein. CFTR, an adenosine triphosphate binding anion channel, has multiple functions, but primarily regulates the movement of chloride anions, thiocyanate and bicarbonate across luminal cell membranes. Additional roles include effects on other electrolyte channels such as the epithelial sodium channel (ENaC) and on pulmonary innate immunity. Inappropriate luminal anion movement leads to elevated sweat chloride concentrations, dehydrated airway surface liquid, overall viscous mucous production, and inspissated bile and pancreatic secretions. As a result, patients develop the well-known CF symptoms and disease-defining complications such as chronic cough, oily stools, recurrent pulmonary infections, bronchiectasis, chronic sinusitis and malnutrition. Traditionally, CF has been symptomatically managed, but over the past 6 years those with CF have been offered a new mode of therapy; CFTR protein modulation. These medications affect the basic defect in CF: abnormal CFTR function. Ivacaftor, approved for use in the United States in 2012, is the first medication in CF history to improve CFTR function at the molecular level. Its study and approval were followed by two additional CFTR modulators, lumacaftor/ivacaftor and tezacaftor/ivacaftor. To effectively use currently available CF therapies, clinicians should be familiar with the side effects of the drugs and their impacts on patient outcomes. As many new modulators are on the horizon, this information will equip providers to discuss the benefits and shortcomings of modulator therapy especially in the context of limited healthcare resources.
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Muntoni F, Desguerre I, Guglieri M, Osorio AN, Kirschner J, Tulinius M, Buccella F, Elfring G, Werner C, Schilling T, Trifillis P, Zhang O, Delage A, Santos CL, Mercuri E. Ataluren use in patients with nonsense mutation Duchenne muscular dystrophy: patient demographics and characteristics from the STRIDE Registry. J Comp Eff Res 2019; 8:1187-1200. [DOI: 10.2217/cer-2019-0086] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aim: Strategic Targeting of Registries and International Database of Excellence (STRIDE) is an ongoing, multicenter registry providing real-world evidence regarding ataluren use in patients with nonsense mutation Duchenne muscular dystrophy (DMD) in clinical practice (NCT02369731). Here, we describe the initial demographic characteristics of the registry population. Patients & methods: Patients will be followed up from enrollment for ≥5 years or until study withdrawal. Results & conclusion: As of 9 July 2018, 213 DMD boys were enrolled from 11 countries. Mean (standard deviation) ages at first symptoms and at study treatment start were 2.7 (1.7) years and 9.8 (3.7) years, respectively. Corticosteroids were used by 190 patients (89.2%) before data cut-off. Mean (standard deviation) ataluren exposure was 639.0 (362.9) days. Six patients withdrew. STRIDE is the first drug registry for patients with DMD and represents the largest real-world registry of patients with nmDMD to date.
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Affiliation(s)
- Francesco Muntoni
- Dubowitz Neuromuscular Centre & MRC Centre for Neuromuscular Diseases, University College London, Institute of Child Health & Great Ormond Street Hospital for Children Foundation Trust, 30 Guildford Street, London WC1N 1EH, UK
- NIHR Great Ormond Street Hospital Biomedical Research Centre, Great Ormond Street Institute of Child Health, University College London, Great Ormond Street Hospital Trust, London, UK
| | - Isabelle Desguerre
- APHP Necker – Enfants Malades Hospital, Paris V Descartes University, Neuromuscular Network FILNEMUS, Paris, France
| | - Michela Guglieri
- The John Walton Muscular Dystrophy Research Centre, Newcastle University & Newcastle Upon Tyne Hospitals, Newcastle Upon Tyne, UK
| | - Andrés Nascimento Osorio
- Hospital Sant Joan de Déu Unidad de Patología Neuromuscular, Universidad de Barcelona, CIBERER, ISCIII, Barcelona, Spain
| | - Janbernd Kirschner
- Medical Center – University of Freiburg, Faculty of Medicine, Freiburg, Germany
| | - Már Tulinius
- Department of Pediatrics, Gothenburg University, Queen Silvia Children’s Hospital, Gothenburg, Sweden
| | | | - Gary Elfring
- PTC Therapeutics Inc., South Plainfield, NJ 07080-2449, USA
| | | | | | | | - Olivia Zhang
- PTC Therapeutics Inc., South Plainfield, NJ 07080-2449, USA
| | | | | | - Eugenio Mercuri
- Department of Pediatric Neurology, Catholic University, Rome, Italy
- Centro Clinico Nemo, Policlinico Universitario A Gemelli IRCCS, Rome, Italy
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