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Andrea ZA, Matteo FY, Alessandra B, Carlo PS. Molecular mechanisms and therapeutic strategies for neuromuscular diseases. Cell Mol Life Sci 2024; 81:198. [PMID: 38678519 PMCID: PMC11056344 DOI: 10.1007/s00018-024-05229-9] [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: 01/02/2024] [Revised: 03/14/2024] [Accepted: 04/07/2024] [Indexed: 05/01/2024]
Abstract
Neuromuscular diseases encompass a heterogeneous array of disorders characterized by varying onset ages, clinical presentations, severity, and progression. While these conditions can stem from acquired or inherited causes, this review specifically focuses on disorders arising from genetic abnormalities, excluding metabolic conditions. The pathogenic defect may primarily affect the anterior horn cells, the axonal or myelin component of peripheral nerves, the neuromuscular junction, or skeletal and/or cardiac muscles. While inherited neuromuscular disorders have been historically deemed not treatable, the advent of gene-based and molecular therapies is reshaping the treatment landscape for this group of condition. With the caveat that many products still fail to translate the positive results obtained in pre-clinical models to humans, both the technological development (e.g., implementation of tissue-specific vectors) as well as advances on the knowledge of pathogenetic mechanisms form a collective foundation for potentially curative approaches to these debilitating conditions. This review delineates the current panorama of therapies targeting the most prevalent forms of inherited neuromuscular diseases, emphasizing approved treatments and those already undergoing human testing, offering insights into the state-of-the-art interventions.
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Affiliation(s)
- Zambon Alberto Andrea
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Institute for Experimental Neurology, Inspe, Milan, Italy
- Neurology Department, San Raffaele Scientific Institute, Milan, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | - Falzone Yuri Matteo
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Institute for Experimental Neurology, Inspe, Milan, Italy
- Neurology Department, San Raffaele Scientific Institute, Milan, Italy
| | - Bolino Alessandra
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Institute for Experimental Neurology, Inspe, Milan, Italy
- Vita-Salute San Raffaele University, Milan, Italy
| | - Previtali Stefano Carlo
- Division of Neuroscience, IRCCS San Raffaele Scientific Institute, Institute for Experimental Neurology, Inspe, Milan, Italy.
- Neurology Department, San Raffaele Scientific Institute, Milan, Italy.
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2
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Klementieva NV, Lunev EA, Shmidt AA, Loseva EM, Savchenko IM, Svetlova EA, Galkin II, Polikarpova AV, Usachev EV, Vassilieva SG, Marina VI, Dzhenkova MA, Romanova AD, Agutin AV, Timakova AA, Reshetov DA, Egorova TV, Bardina MV. RNA Interference Effectors Selectively Silence the Pathogenic Variant GNAO1 c.607 G > A In Vitro. Nucleic Acid Ther 2024; 34:90-99. [PMID: 38215303 DOI: 10.1089/nat.2023.0043] [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] [Indexed: 01/14/2024] Open
Abstract
RNA interference (RNAi)-based therapeutics hold the potential for dominant genetic disorders, enabling sequence-specific inhibition of pathogenic gene products. We aimed to direct RNAi for the selective suppression of the heterozygous GNAO1 c.607 G > A variant causing GNAO1 encephalopathy. By screening short interfering RNA (siRNA), we showed that GNAO1 c.607G>A is a druggable target for RNAi. The si1488 candidate achieved at least twofold allelic discrimination and downregulated mutant protein to 35%. We created vectorized RNAi by incorporating the si1488 sequence into the short hairpin RNA (shRNA) in the adeno-associated virus (AAV) vector. The shRNA stem and loop were modified to improve the transcription, processing, and guide strand selection. All tested shRNA constructs demonstrated selectivity toward mutant GNAO1, while tweaking hairpin structure only marginally affected the silencing efficiency. The selectivity of shRNA-mediated silencing was confirmed in the context of AAV vector transduction. To conclude, RNAi effectors ranging from siRNA to AAV-RNAi achieve suppression of the pathogenic GNAO1 c.607G>A and discriminate alleles by the single-nucleotide substitution. For gene therapy development, it is crucial to demonstrate the benefit of these RNAi effectors in patient-specific neurons and animal models of the GNAO1 encephalopathy.
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Affiliation(s)
- Natalia V Klementieva
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
| | - Evgenii A Lunev
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Anna A Shmidt
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | | | - Irina M Savchenko
- Marlin Biotech LLC, Sochi, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Ekaterina A Svetlova
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
| | - Ivan I Galkin
- Marlin Biotech LLC, Sochi, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Anna V Polikarpova
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
| | - Evgeny V Usachev
- Laboratory of Translational Biomedicine, Gamaleya National Research Center for Epidemiology, Moscow, Russia
| | - Svetlana G Vassilieva
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
| | | | - Marina A Dzhenkova
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
| | - Anna D Romanova
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
| | - Anton V Agutin
- State Budgetary Healthcare Institution of Moscow Region "Balashikha Hospital," Balashikha, Russia
| | - Anna A Timakova
- Institute for Regenerative Medicine, Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | | | - Tatiana V Egorova
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
| | - Maryana V Bardina
- Laboratory of Modeling and Gene Therapy of Hereditary Diseases, Institute of Gene Biology Russian Academy of Sciences, Moscow, Russia
- Marlin Biotech LLC, Sochi, Russia
- Center for Precision Genome Editing and Genetic Technologies for Biomedicine, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
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3
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Cohen J, Huang S, Koczwara KE, Woods KT, Ho V, Woodman KG, Arbiser JL, Daman K, Lek M, Emerson CP, DeSimone AM. Flavones provide resistance to DUX4-induced toxicity via an mTor-independent mechanism. Cell Death Dis 2023; 14:749. [PMID: 37973788 PMCID: PMC10654915 DOI: 10.1038/s41419-023-06257-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 10/10/2023] [Accepted: 10/31/2023] [Indexed: 11/19/2023]
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is among the most common of the muscular dystrophies, affecting nearly 1 in 8000 individuals, and is a cause of profound disability. Genetically, FSHD is linked to the contraction and/or epigenetic de-repression of the D4Z4 repeat array on chromosome 4, thereby allowing expression of the DUX4 gene in skeletal muscle. If the DUX4 transcript incorporates a stabilizing polyadenylation site the myotoxic DUX4 protein will be synthesized, resulting in muscle wasting. The mechanism of toxicity remains unclear, as many DUX4-induced cytopathologies have been described, however cell death does primarily occur through caspase 3/7-dependent apoptosis. To date, most FSHD therapeutic development has focused on molecular methods targeting DUX4 expression or the DUX4 transcript, while therapies targeting processes downstream of DUX4 activity have received less attention. Several studies have demonstrated that inhibition of multiple signal transduction pathways can ameliorate DUX4-induced toxicity, and thus compounds targeting these pathways have the potential to be developed into FSHD therapeutics. To this end, we have screened a group of small molecules curated based on their reported activity in relevant pathways and/or structural relationships with known toxicity-modulating molecules. We have identified a panel of five compounds that function downstream of DUX4 activity to inhibit DUX4-induced toxicity. Unexpectedly, this effect was mediated through an mTor-independent mechanism that preserved expression of ULK1 and correlated with an increase in a marker of active cellular autophagy. This identifies these flavones as compounds of interest for therapeutic development, and potentially identifies the autophagy pathway as a target for therapeutics.
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Affiliation(s)
- Justin Cohen
- Department of Genetics, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Shushu Huang
- Department of Genetics, Yale School of Medicine, New Haven, CT, 06510, USA
| | | | - Kristen T Woods
- Wellstone Muscular Dystrophy Program, Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Li Weibo Institute for Rare Disease Research University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Vincent Ho
- Department of Genetics, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Keryn G Woodman
- Department of Genetics, Yale School of Medicine, New Haven, CT, 06510, USA
| | | | - Katelyn Daman
- Wellstone Muscular Dystrophy Program, Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Li Weibo Institute for Rare Disease Research University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Monkol Lek
- Department of Genetics, Yale School of Medicine, New Haven, CT, 06510, USA
| | - Charles P Emerson
- Wellstone Muscular Dystrophy Program, Department of Neurology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Li Weibo Institute for Rare Disease Research University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Alec M DeSimone
- Department of Genetics, Yale School of Medicine, New Haven, CT, 06510, USA.
- Modalis Therapeutics, Waltham, MA, USA.
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4
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Duranti E, Villa C. Influence of DUX4 Expression in Facioscapulohumeral Muscular Dystrophy and Possible Treatments. Int J Mol Sci 2023; 24:ijms24119503. [PMID: 37298453 DOI: 10.3390/ijms24119503] [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: 04/20/2023] [Revised: 05/23/2023] [Accepted: 05/29/2023] [Indexed: 06/12/2023] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) represents the third most common form of muscular dystrophy and is characterized by muscle weakness and atrophy. FSHD is caused by the altered expression of the transcription factor double homeobox 4 (DUX4), which is involved in several significantly altered pathways required for myogenesis and muscle regeneration. While DUX4 is normally silenced in the majority of somatic tissues in healthy individuals, its epigenetic de-repression has been linked to FSHD, resulting in DUX4 aberrant expression and cytotoxicity in skeletal muscle cells. Understanding how DUX4 is regulated and functions could provide useful information not only to further understand FSHD pathogenesis, but also to develop therapeutic approaches for this disorder. Therefore, this review discusses the role of DUX4 in FSHD by examining the possible molecular mechanisms underlying the disease as well as novel pharmacological strategies targeting DUX4 aberrant expression.
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Affiliation(s)
- Elisa Duranti
- School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy
| | - Chiara Villa
- School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy
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5
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Tihaya MS, Mul K, Balog J, de Greef JC, Tapscott SJ, Tawil R, Statland JM, van der Maarel SM. Facioscapulohumeral muscular dystrophy: the road to targeted therapies. Nat Rev Neurol 2023; 19:91-108. [PMID: 36627512 DOI: 10.1038/s41582-022-00762-2] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/07/2022] [Indexed: 01/11/2023]
Abstract
Advances in the molecular understanding of facioscapulohumeral muscular dystrophy (FSHD) have revealed that FSHD results from epigenetic de-repression of the DUX4 gene in skeletal muscle, which encodes a transcription factor that is active in early embryonic development but is normally silenced in almost all somatic tissues. These advances also led to the identification of targets for disease-altering therapies for FSHD, as well as an improved understanding of the molecular mechanism of the disease and factors that influence its progression. Together, these developments led the FSHD research community to shift its focus towards the development of disease-modifying treatments for FSHD. This Review presents advances in the molecular and clinical understanding of FSHD, discusses the potential targeted therapies that are currently being explored, some of which are already in clinical trials, and describes progress in the development of FSHD-specific outcome measures and assessment tools for use in future clinical trials.
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Affiliation(s)
- Mara S Tihaya
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Karlien Mul
- Department of Neurology, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Judit Balog
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Jessica C de Greef
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Stephen J Tapscott
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, Rochester, NY, USA
| | - Jeffrey M Statland
- Department of Neurology, University of Kansas Medical Center, Kansas City, KS, USA
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6
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Azzag K, Bosnakovski D, Tungtur S, Salama P, Kyba M, Perlingeiro RCR. Transplantation of PSC-derived myogenic progenitors counteracts disease phenotypes in FSHD mice. NPJ Regen Med 2022; 7:43. [PMID: 36056021 PMCID: PMC9440030 DOI: 10.1038/s41536-022-00249-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Accepted: 08/08/2022] [Indexed: 12/02/2022] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is a genetically dominant progressive myopathy caused by improper silencing of the DUX4 gene, leading to fibrosis, muscle atrophy, and fatty replacement. Approaches focused on muscle regeneration through the delivery of stem cells represent an attractive therapeutic option for muscular dystrophies. To investigate the potential for cell transplantation in FSHD, we have used the doxycycline-regulated iDUX4pA-HSA mouse model in which low-level DUX4 can be induced in skeletal muscle. We find that mouse pluripotent stem cell (PSC)-derived myogenic progenitors engraft in muscle actively undergoing DUX4-mediated degeneration. Donor-derived muscle tissue displayed reduced fibrosis and importantly, engrafted muscles showed improved contractile specific force compared to non-transplanted controls. These data demonstrate the feasibility of replacement of diseased muscle with PSC-derived myogenic progenitors in a mouse model for FSHD, and highlight the potential for the clinical benefit of such a cell therapy approach.
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Affiliation(s)
- Karim Azzag
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Darko Bosnakovski
- Lillehei Heart Institute, Department of Pediatrics, University of Minnesota, Minneapolis, MN, USA
| | - Sudheer Tungtur
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Peter Salama
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Michael Kyba
- Lillehei Heart Institute, Department of Pediatrics, University of Minnesota, Minneapolis, MN, USA.,Stem Cell Institute, University of Minnesota, Minneapolis, MN, USA
| | - Rita C R Perlingeiro
- Lillehei Heart Institute, Department of Medicine, University of Minnesota, Minneapolis, MN, USA. .,Stem Cell Institute, University of Minnesota, Minneapolis, MN, USA.
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7
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Lu-Nguyen N, Dickson G, Malerba A, Popplewell L. Long-Term Systemic Treatment of a Mouse Model Displaying Chronic FSHD-like Pathology with Antisense Therapeutics That Inhibit DUX4 Expression. Biomedicines 2022; 10:biomedicines10071623. [PMID: 35884928 PMCID: PMC9313434 DOI: 10.3390/biomedicines10071623] [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: 06/10/2022] [Revised: 07/03/2022] [Accepted: 07/05/2022] [Indexed: 11/29/2022] Open
Abstract
Silencing the expression of the double homeobox 4 (DUX4) gene offers great potential for the treatment of facioscapulohumeral muscular dystrophy (FSHD). Several research groups have recently reported promising results using systemic antisense therapy in a transgenic small animal model of FSHD, the ACTA1-MCM/FLExDUX4 mouse model. However, the treatment was applied in non-DUX4-induced mice or shortly after DUX4 activation, which resulted in conditions that do not correctly represent the situation in a clinic. Here, we generated progressive FSHD-like pathology in ACTA1-MCM/FLExDUX4 mice and then treated the animals with vivoPMO-PACS4, an antisense compound that efficiently downregulates DUX4. To best mimic the translation of this treatment in clinical settings, the systemic antisense oligonucleotide administration was delayed to 3 weeks after the DUX4 activation so that the pathology was established at the time of the treatment. The chronic administration of vivoPMO-PACS4 for 8 weeks downregulated the DUX4 expression by 60%. Consequently, the treated mice showed an increase by 18% in body-wide muscle mass and 32% in muscle strength, and a reduction in both myofiber central nucleation and muscle fibrosis by up to 29% and 37%, respectively. Our results in a more suitable model of FSHD pathology confirm the efficacy of vivoPMO-PACS4 administration, and highlight the significant benefit provided by the long-term treatment of the disease.
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Affiliation(s)
- Ngoc Lu-Nguyen
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham TW20 0EX, UK; (N.L.-N.); (G.D.)
| | - George Dickson
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham TW20 0EX, UK; (N.L.-N.); (G.D.)
| | - Alberto Malerba
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham TW20 0EX, UK; (N.L.-N.); (G.D.)
- Correspondence: (A.M.); (L.P.)
| | - Linda Popplewell
- Department of Biological Sciences, School of Life Sciences and the Environment, Royal Holloway University of London, Egham TW20 0EX, UK; (N.L.-N.); (G.D.)
- National Horizons Centre, Teesside University, Darlington DL1 1HG, UK
- Correspondence: (A.M.); (L.P.)
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8
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Fan Z, Jiang C, Wang Y, Wang K, Marsh J, Zhang D, Chen X, Nie L. Engineered extracellular vesicles as intelligent nanosystems for next-generation nanomedicine. NANOSCALE HORIZONS 2022; 7:682-714. [PMID: 35662310 DOI: 10.1039/d2nh00070a] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Extracellular vesicles (EVs), as natural carriers of bioactive cargo, have a unique micro/nanostructure, bioactive composition, and characteristic morphology, as well as fascinating physical, chemical and biochemical features, which have shown promising application in the treatment of a wide range of diseases. However, native EVs have limitations such as lack of or inefficient cell targeting, on-demand delivery, and therapeutic feedback. Recently, EVs have been engineered to contain an intelligent core, enabling them to (i) actively target sites of disease, (ii) respond to endogenous and/or exogenous signals, and (iii) provide treatment feedback for optimal function in the host. These advances pave the way for next-generation nanomedicine and offer promise for a revolution in drug delivery. Here, we summarise recent research on intelligent EVs and discuss the use of "intelligent core" based EV systems for the treatment of disease. We provide a critique about the construction and properties of intelligent EVs, and challenges in their commercialization. We compare the therapeutic potential of intelligent EVs to traditional nanomedicine and highlight key advantages for their clinical application. Collectively, this review aims to provide a new insight into the design of next-generation EV-based theranostic platforms for disease treatment.
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Affiliation(s)
- Zhijin Fan
- School of Medicine, South China University of Technology, Guangzhou 510006, P. R. China.
- Research Center of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, P. R. China
| | - Cheng Jiang
- School of Life and Health Sciences, The Chinese University of Hong Kong, Shenzhen 518172, China
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Yichao Wang
- Department of Clinical Laboratory Medicine, Tai Zhou Central Hospital (Taizhou University Hospital), Taizhou 318000, P. R. China
| | - Kaiyuan Wang
- Department of Pharmaceutics, Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, 110016, P. R. China
| | - Jade Marsh
- Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Da Zhang
- The United Innovation of Mengchao Hepatobiliary Technology Key Laboratory of Fujian Province, Mengchao Hepatobiliary Hospital of Fujian Medical University, Fuzhou 350025, P. R. China.
| | - Xin Chen
- School of Chemical Engineering and Technology, Shaanxi Key Laboratory of Energy Chemical Process Intensification, Institute of Polymer Science in Chemical Engineering, Xi'an Jiao Tong University, Xi'an 710049, P. R. China.
| | - Liming Nie
- Research Center of Medical Sciences, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou 510080, P. R. China
- School of Medicine, South China University of Technology, Guangzhou 510006, P. R. China.
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9
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Himeda CL, Jones PL. FSHD Therapeutic Strategies: What Will It Take to Get to Clinic? J Pers Med 2022; 12:jpm12060865. [PMID: 35743650 PMCID: PMC9225474 DOI: 10.3390/jpm12060865] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 05/17/2022] [Accepted: 05/20/2022] [Indexed: 12/10/2022] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is arguably one of the most challenging genetic diseases to understand and treat. The disease is caused by epigenetic dysregulation of a macrosatellite repeat, either by contraction of the repeat or by mutations in silencing proteins. Both cases lead to chromatin relaxation and, in the context of a permissive allele, pathogenic misexpression of DUX4 in skeletal muscle. The complex nature of the locus and the fact that FSHD is a toxic, gain-of-function disease present unique challenges for the design of therapeutic strategies. There are three major DUX4-targeting avenues of therapy for FSHD: small molecules, oligonucleotide therapeutics, and CRISPR-based approaches. Here, we evaluate the preclinical progress of each avenue, and discuss efforts being made to overcome major hurdles to translation.
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10
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Stavrou M, Kagiava A, Choudury SG, Jennings MJ, Wallace LM, Fowler AM, Heslegrave A, Richter J, Tryfonos C, Christodoulou C, Zetterberg H, Horvath R, Harper SQ, Kleopa KA. A translatable RNAi-driven gene therapy silences PMP22/Pmp22 genes and improves neuropathy in CMT1A mice. J Clin Invest 2022; 132:159814. [PMID: 35579942 PMCID: PMC9246392 DOI: 10.1172/jci159814] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2022] [Accepted: 05/12/2022] [Indexed: 11/17/2022] Open
Abstract
Charcot-Marie-Tooth disease type 1A (CMT1A), the most common inherited demyelinating peripheral neuropathy, is caused by PMP22 gene duplication. Overexpression of WT PMP22 in Schwann cells destabilizes the myelin sheath, leading to demyelination and ultimately to secondary axonal loss and disability. No treatments currently exist that modify the disease course. The most direct route to CMT1A therapy will involve reducing PMP22 to normal levels. To accomplish this, we developed a gene therapy strategy to reduce PMP22 using artificial miRNAs targeting human PMP22 and mouse Pmp22 mRNAs. Our lead therapeutic miRNA, miR871, was packaged into an adeno-associated virus 9 (AAV9) vector and delivered by lumbar intrathecal injection into C61-het mice, a model of CMT1A. AAV9-miR871 efficiently transduced Schwann cells in C61-het peripheral nerves and reduced human and mouse PMP22 mRNA and protein levels. Treatment at early and late stages of the disease significantly improved multiple functional outcome measures and nerve conduction velocities. Furthermore, myelin pathology in lumbar roots and femoral motor nerves was ameliorated. The treated mice also showed reductions in circulating biomarkers of CMT1A. Taken together, our data demonstrate that AAV9-miR871–driven silencing of PMP22 rescues a CMT1A model and provides proof of principle for treating CMT1A using a translatable gene therapy approach.
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Affiliation(s)
- Marina Stavrou
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Alexia Kagiava
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Sarah G Choudury
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, United States of America
| | - Matthew J Jennings
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
| | - Lindsay M Wallace
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, United States of America
| | - Allison M Fowler
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, United States of America
| | - Amanda Heslegrave
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, London, United Kingdom
| | - Jan Richter
- Department of Molecular Virology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Christina Tryfonos
- Department of Molecular Virology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Christina Christodoulou
- Department of Molecular Virology, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Henrik Zetterberg
- Institute of Laboratory Medicine, Göteborgs University, Göteborg, Sweden
| | - Rita Horvath
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, United Kingdom
| | - Scott Q Harper
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, United States of America
| | - Kleopas A Kleopa
- Neuroscience Department, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
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11
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Lu-Nguyen N, Malerba A, Antoni Pineda M, Dickson G, Popplewell LJ. Improving molecular and histopathology in diaphragm muscle of the double transgenic ACTA1-MCM/FLExDUX4 mouse model of FSHD with systemic antisense therapy. Hum Gene Ther 2022; 33:923-935. [PMID: 35078334 DOI: 10.1089/hum.2021.251] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is a rare muscle dystrophy causing muscle weakness initially in the face, shoulders and upper arms, and extended to lower body muscles as the disease progresses. Respiratory restriction in FSHD is increasingly reported to be more common and severe than previously thought, with the involvement of diaphragm weakness in pulmonary insufficiency being under debate. As aberrant expression of the double homeobox 4 (DUX4) gene is the prime cause of FSHD, we and others have developed numerous strategies and reported promising results on downregulating DUX4 expression in both cellular and animal models of FSHD. However, the effect of DUX4 and anti-DUX4 approaches on diaphragm muscle has not been elucidated. Here we show that toxic DUX4 expression causes pathology that affects the diaphragm of ACTA1-MCM/FLExDUX4 mouse model of FSHD at both molecular and histological levels. Of importance, a systemic antisense treatment that suppresses DUX4 and target genes expression by 50% significantly improves muscle regeneration and muscle fibrosis, and prevents modification in myofiber type composition, supporting its development as a treatment for FSHD.
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Affiliation(s)
- Ngoc Lu-Nguyen
- Royal Holloway University of London, 3162, Department of Biological Sciences, Egham, Surrey, United Kingdom of Great Britain and Northern Ireland;
| | - Alberto Malerba
- Royal Holloway University of London, 3162, Department of Biological Sciences, Egham, Surrey, United Kingdom of Great Britain and Northern Ireland;
| | - Marina Antoni Pineda
- Royal Holloway University of London, 3162, Department of Biological Sciences, Egham, Surrey, United Kingdom of Great Britain and Northern Ireland;
| | - George Dickson
- Royal Holloway University of London, 3162, Department of Biological Sciences, Egham, Surrey, United Kingdom of Great Britain and Northern Ireland;
| | - Linda J Popplewell
- Royal Holloway University of London, 3162, Department of Biological Sciences, Egham, Surrey, United Kingdom of Great Britain and Northern Ireland;
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12
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Jagannathan S, de Greef JC, Hayward LJ, Yokomori K, Gabellini D, Mul K, Sacconi S, Arjomand J, Kinoshita J, Harper SQ. Meeting report: the 2021 FSHD International Research Congress. Skelet Muscle 2022; 12:1. [PMID: 35039091 PMCID: PMC8762812 DOI: 10.1186/s13395-022-00287-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 12/21/2021] [Indexed: 03/15/2023] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is the second most common genetic myopathy, characterized by slowly progressing and highly heterogeneous muscle wasting with a typical onset in the late teens/early adulthood [1]. Although the etiology of the disease for both FSHD type 1 and type 2 has been attributed to gain-of-toxic function stemming from aberrant DUX4 expression, the exact pathogenic mechanisms involved in muscle wasting have yet to be elucidated [2–4]. The 2021 FSHD International Research Congress, held virtually on June 24–25, convened over 350 researchers and clinicians to share the most recent advances in the understanding of the disease mechanism, discuss the proliferation of interventional strategies and refinement of clinical outcome measures, including results from the ReDUX4 trial, a phase 2b clinical trial of losmapimod in FSHD [NCT04003974].
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Affiliation(s)
- Sujatha Jagannathan
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, CO, 80045, USA
| | - Jessica C de Greef
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Lawrence J Hayward
- Department of Neurology and Wellstone Center for FSHD, University of Massachusetts Medical School, Worcester, MA, 01655, USA
| | - Kyoko Yokomori
- Department of Biological Chemistry, School of Medicine, University of California, Irvine, CA, 92697, USA
| | - Davide Gabellini
- Division of Genetics and Cell Biology, IRCCS San Raffaele Scientific Institute, Milan, Italy
| | - Karlien Mul
- Department of Neurology, Donders Institute for Brain, Cognition, and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Sabrina Sacconi
- Nice University Hospital/Institute of Research on Cancer and Aging of Nice, Nice, France
| | | | | | - Scott Q Harper
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH, 43205, USA.
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13
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Saad NY, Al-Kharsan M, Garwick-Coppens SE, Chermahini GA, Harper MA, Palo A, Boudreau RL, Harper SQ. Human miRNA miR-675 inhibits DUX4 expression and may be exploited as a potential treatment for Facioscapulohumeral muscular dystrophy. Nat Commun 2021; 12:7128. [PMID: 34880230 PMCID: PMC8654987 DOI: 10.1038/s41467-021-27430-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 11/18/2021] [Indexed: 01/02/2023] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is a potentially devastating myopathy caused by de-repression of the DUX4 gene in skeletal muscles. Effective therapies will likely involve DUX4 inhibition. RNA interference (RNAi) is one powerful approach to inhibit DUX4, and we previously described a RNAi gene therapy to achieve DUX4 silencing in FSHD cells and mice using engineered microRNAs. Here we report a strategy to direct RNAi against DUX4 using the natural microRNA miR-675, which is derived from the lncRNA H19. Human miR-675 inhibits DUX4 expression and associated outcomes in FSHD cell models. In addition, miR-675 delivery using gene therapy protects muscles from DUX4-associated death in mice. Finally, we show that three known miR-675-upregulating small molecules inhibit DUX4 and DUX4-activated FSHD biomarkers in FSHD patient-derived myotubes. To our knowledge, this is the first study demonstrating the use of small molecules to suppress a dominant disease gene using an RNAi mechanism.
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Affiliation(s)
- Nizar Y. Saad
- grid.240344.50000 0004 0392 3476Center for Gene Therapy, the Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH USA
| | - Mustafa Al-Kharsan
- grid.240344.50000 0004 0392 3476Center for Gene Therapy, the Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH USA ,grid.266832.b0000 0001 2188 8502Department of Neurology, University of New Mexico Health Sciences Center, Albuquerque, NM USA
| | - Sara E. Garwick-Coppens
- grid.240344.50000 0004 0392 3476Center for Gene Therapy, the Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH USA
| | - Gholamhossein Amini Chermahini
- grid.240344.50000 0004 0392 3476Center for Gene Therapy, the Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH USA
| | - Madison A. Harper
- grid.240344.50000 0004 0392 3476Center for Gene Therapy, the Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH USA
| | - Andrew Palo
- grid.240344.50000 0004 0392 3476Center for Gene Therapy, the Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH USA
| | - Ryan L. Boudreau
- grid.214572.70000 0004 1936 8294Department of Internal Medicine, Fraternal Order of Eagles Diabetes Research Center, Abboud Cardiovascular Research Center, Carver College of Medicine, University of Iowa, Iowa City, IA USA
| | - Scott Q. Harper
- grid.240344.50000 0004 0392 3476Center for Gene Therapy, the Abigail Wexner Research Institute at Nationwide Children’s Hospital, Columbus, OH USA ,grid.261331.40000 0001 2285 7943Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH USA
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14
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Mitra S, Gumusgoz E, Minassian BA. Lafora disease: Current biology and therapeutic approaches. Rev Neurol (Paris) 2021; 178:315-325. [PMID: 34301405 DOI: 10.1016/j.neurol.2021.06.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 05/21/2021] [Accepted: 06/16/2021] [Indexed: 12/19/2022]
Abstract
The ubiquitin system impacts most cellular processes and is altered in numerous neurodegenerative diseases. However, little is known about its role in neurodegenerative diseases due to disturbances of glycogen metabolism such as Lafora disease (LD). In LD, insufficiently branched and long-chained glycogen forms and precipitates into insoluble polyglucosan bodies (Lafora bodies), which drive neuroinflammation, neurodegeneration and epilepsy. LD is caused by mutations in the gene encoding the glycogen phosphatase laforin or the gene coding for the laforin interacting partner ubiquitin E3 ligase malin. The role of the malin-laforin complex in regulating glycogen structure remains with full of gaps. In this review we bring together the disparate body of data on these two proteins and propose a mechanistic hypothesis of the disease in which malin-laforin's role to monitor and prevent over-elongation of glycogen branch chains, which drive glycogen molecules to precipitate and accumulate into Lafora bodies. We also review proposed connections between Lafora bodies and the ensuing neuroinflammation, neurodegeneration and intractable epilepsy. Finally, we review the exciting activities in developing therapies for Lafora disease based on replacing the missing genes, slowing the enzyme - glycogen synthase - that over-elongates glycogen branches, and introducing enzymes that can digest Lafora bodies. Much more work is needed to fill the gaps in glycogen metabolism in which laforin and malin operate. However, knowledge appears already adequate to advance disease course altering therapies for this catastrophic fatal disease.
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Affiliation(s)
- S Mitra
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - E Gumusgoz
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
| | - B A Minassian
- Division of Neurology, Department of Pediatrics, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA.
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15
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Blokhuis AM, Deenen JCW, Voermans NC, van Engelen BGM, Kievit W, Groothuis JT. The socioeconomic burden of facioscapulohumeral muscular dystrophy. J Neurol 2021; 268:4778-4788. [PMID: 34043041 PMCID: PMC8563627 DOI: 10.1007/s00415-021-10591-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 03/19/2021] [Accepted: 05/03/2021] [Indexed: 12/23/2022]
Abstract
BACKGROUND Promising genetic therapies are being investigated in facioscapulohumeral muscular dystrophy (FSHD). However, the current cost of illness is largely unknown. OBJECTIVE This study aimed at determining the socioeconomic burden of FSHD. METHODS Adult patients with FSHD from the Dutch FSHD registry were invited to complete a questionnaire on medical consumption, work productivity and health-related quality of life (HR-QoL) using the EQ-5D-5L. Associated costs were calculated from a societal perspective. A generalized linear model was fitted to the data to investigate whether level of mobility was related to annual costs of illness. RESULTS 172 patients with FSHD completed the questionnaire (response rate 65%). The per-patient annual direct medical costs of FSHD were estimated at €12,077, direct non-medical costs at €9179 and indirect costs at €5066, adding up to a total cost of illness of €26,322 per patient per year. The direct costs of illness were €21,256, approximately five times higher than the mean per-capita health expenditures in the Netherlands. Major cost-driving factors were formal home care and informal care. A decreased level of mobility was associated with higher direct costs of illness. HR-QoL was significantly reduced in patients with FSHD with a median health utility value of 0.63. CONCLUSIONS We show that FSHD is associated with substantial direct and indirect socioeconomic costs as well as a reduction in HR-QoL. These findings are important for health care decision makers and aids in allocation of research funds and evaluation of the cost-effectiveness of novel therapies.
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Affiliation(s)
- Anna M Blokhuis
- Department of Rehabilitation, Sint Maartenskliniek, Nijmegen, The Netherlands. .,Donders Institute for Brain, Cognition and Behaviour, Department of Rehabilitation, Radboud university medical center, Nijmegen, The Netherlands.
| | - Johanna C W Deenen
- Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Radboud university medical center, Nijmegen, The Netherlands
| | - Nicol C Voermans
- Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Radboud university medical center, Nijmegen, The Netherlands
| | - Baziel G M van Engelen
- Donders Institute for Brain, Cognition and Behaviour, Department of Neurology, Radboud university medical center, Nijmegen, The Netherlands
| | - Wietske Kievit
- Department for Health Evidence, Radboud Institute for Health Sciences, Radboud university medical center, Nijmegen, The Netherlands
| | - Jan T Groothuis
- Donders Institute for Brain, Cognition and Behaviour, Department of Rehabilitation, Radboud university medical center, Nijmegen, The Netherlands
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16
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Karpukhina A, Tiukacheva E, Dib C, Vassetzky YS. Control of DUX4 Expression in Facioscapulohumeral Muscular Dystrophy and Cancer. Trends Mol Med 2021; 27:588-601. [PMID: 33863674 DOI: 10.1016/j.molmed.2021.03.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Revised: 03/10/2021] [Accepted: 03/16/2021] [Indexed: 12/13/2022]
Abstract
DUX4, a gene encoding a transcription factor involved in early embryogenesis, is located within the D4Z4 subtelomeric repeat on chromosome 4q35. In most healthy somatic tissues, DUX4 is heavily repressed by multiple genetic and epigenetic mechanisms, and its aberrant expression is linked to facioscapulohumeral muscular dystrophy (FSHD) where it has been extensively studied. Recently, DUX4 expression has been implicated in oncogenesis, although this is much less explored. In this review, we discuss multiple levels of control of DUX4 expression, including enhancer-promoter interactions, DNA methylation, histone modifications, noncoding RNAs, and telomere positioning effect. We also connect disparate data on intrachromosomal contacts involving DUX4 and emphasize the feedback loops in DUX4 regulation. Finally, we bridge data on DUX4 in FSHD and cancer and discuss prospective approaches for future FSHD therapies and the potential outcomes of DUX4 inhibition in cancer.
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Affiliation(s)
- Anna Karpukhina
- UMR 9018, CNRS, Université Paris Saclay, Institut Gustave Roussy, Villejuif F-94805, France; Koltzov Institute of Developmental Biology, Moscow 117334, Russia; Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow 119991, Russia
| | - Eugenia Tiukacheva
- UMR 9018, CNRS, Université Paris Saclay, Institut Gustave Roussy, Villejuif F-94805, France
| | - Carla Dib
- UMR 9018, CNRS, Université Paris Saclay, Institut Gustave Roussy, Villejuif F-94805, France; Stanford University School of Medicine, Stanford, CA 94305-510, USA
| | - Yegor S Vassetzky
- UMR 9018, CNRS, Université Paris Saclay, Institut Gustave Roussy, Villejuif F-94805, France; Koltzov Institute of Developmental Biology, Moscow 117334, Russia.
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17
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Abstract
Increased understanding of disease pathophysiology and advances in gene therapies and drug technologies are revolutionizing treatment of muscular dystrophies and motor neuron disorders (MNDs). New drugs have been approved for Duchenne muscular dystrophy, spinal muscular atrophy, and amyotrophic lateral sclerosis. For other diseases, new targets have been identified, and new therapies are in clinical trials. The impact of such therapies will be fully understood only in the next decades. Cost burden and accessibility are major challenges in the wide application of new drugs. This article reviews advances in gene therapies, newly approved drugs, and therapeutic promises in muscular dystrophies and MNDs.
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18
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Schätzl T, Kaiser L, Deigner HP. Facioscapulohumeral muscular dystrophy: genetics, gene activation and downstream signalling with regard to recent therapeutic approaches: an update. Orphanet J Rare Dis 2021; 16:129. [PMID: 33712050 PMCID: PMC7953708 DOI: 10.1186/s13023-021-01760-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 02/25/2021] [Indexed: 12/12/2022] Open
Abstract
Whilst a disease-modifying treatment for Facioscapulohumeral muscular dystrophy (FSHD) does not exist currently, recent advances in complex molecular pathophysiology studies of FSHD have led to possible therapeutic approaches for its targeted treatment. Although the underlying genetics of FSHD have been researched extensively, there remains an incomplete understanding of the pathophysiology of FSHD in relation to the molecules leading to DUX4 gene activation and the downstream gene targets of DUX4 that cause its toxic effects. In the context of the local proximity of chromosome 4q to the nuclear envelope, a contraction of the D4Z4 macrosatellite induces lower methylation levels, enabling the ectopic expression of DUX4. This disrupts numerous signalling pathways that mostly result in cell death, detrimentally affecting skeletal muscle in affected individuals. In this regard different options are currently explored either to suppress the transcription of DUX4 gene, inhibiting DUX4 protein from its toxic effects, or to alleviate the symptoms triggered by its numerous targets.
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Affiliation(s)
- Teresa Schätzl
- Institute of Precision Medicine, Medical and Life Sciences Faculty, Furtwangen University, Jakob-Kienzle-Straße 17, 78054, Villingen-Schwenningen, Germany
| | - Lars Kaiser
- Institute of Precision Medicine, Medical and Life Sciences Faculty, Furtwangen University, Jakob-Kienzle-Straße 17, 78054, Villingen-Schwenningen, Germany
- Institute of Pharmaceutical Sciences, University of Freiburg, Albertstraße 25, 79104, Freiburg i. Br., Germany
| | - Hans-Peter Deigner
- Institute of Precision Medicine, Medical and Life Sciences Faculty, Furtwangen University, Jakob-Kienzle-Straße 17, 78054, Villingen-Schwenningen, Germany.
- EXIM Department, Fraunhofer Institute IZI, Leipzig, Schillingallee 68, 18057, Rostock, Germany.
- Faculty of Science, Tuebingen University, Auf der Morgenstelle 8, 72076, Tübingen, Germany.
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19
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Lim KRQ, Yokota T. Genetic Approaches for the Treatment of Facioscapulohumeral Muscular Dystrophy. Front Pharmacol 2021; 12:642858. [PMID: 33776777 PMCID: PMC7996372 DOI: 10.3389/fphar.2021.642858] [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: 12/16/2020] [Accepted: 02/01/2021] [Indexed: 12/26/2022] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant disorder characterized by progressive, asymmetric muscle weakness at the face, shoulders, and upper limbs, which spreads to the lower body with age. It is the third most common inherited muscular disorder worldwide. Around 20% of patients are wheelchair-bound, and some present with extramuscular manifestations. FSHD is caused by aberrant expression of the double homeobox protein 4 (DUX4) gene in muscle. DUX4 codes for a transcription factor which, in skeletal muscle, dysregulates numerous signaling activities that culminate in cytotoxicity. Potential treatments for FSHD therefore aim to reduce the expression of DUX4 or the activity of its toxic protein product. In this article, we review how genetic approaches such as those based on oligonucleotide and genome editing technologies have been developed to achieve these goals. We also outline the challenges these therapies are facing on the road to translation, and discuss possible solutions and future directions.
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Affiliation(s)
- Kenji Rowel Q. Lim
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Toshifumi Yokota
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
- The Friends of Garrett Cumming Research and Muscular Dystrophy Canada, HM Toupin Neurological Science Research Chair, Edmonton, AB, Canada
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20
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Cohen J, DeSimone A, Lek M, Lek A. Therapeutic Approaches in Facioscapulohumeral Muscular Dystrophy. Trends Mol Med 2021; 27:123-137. [PMID: 33092966 PMCID: PMC8048701 DOI: 10.1016/j.molmed.2020.09.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 09/14/2020] [Accepted: 09/15/2020] [Indexed: 01/13/2023]
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common types of muscular dystrophy, affecting roughly one in 8000 individuals. The complex underlying genetics and poor mechanistic understanding has caused a bottleneck in therapeutic development. Until the discovery of DUX4 and its causal role in FSHD, most trials were untargeted with limited results. Emerging approaches can learn from these early trials to increase their chance of success. Here, we explore the evolution of FSHD clinical trials from nonspecific anabolic or anti-inflammatory/oxidant strategies to cutting-edge molecular therapies targeting DUX4, and we discuss the importance of clinical outcome measures. With combined advances across multiple facets of FSHD research, the field is now poised to accelerate the process of therapeutic discovery and testing.
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Affiliation(s)
- Justin Cohen
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Alec DeSimone
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Monkol Lek
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA
| | - Angela Lek
- Department of Genetics, Yale School of Medicine, New Haven, CT, USA.
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21
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Kotowska-Zimmer A, Pewinska M, Olejniczak M. Artificial miRNAs as therapeutic tools: Challenges and opportunities. WILEY INTERDISCIPLINARY REVIEWS-RNA 2021; 12:e1640. [PMID: 33386705 DOI: 10.1002/wrna.1640] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 12/02/2020] [Accepted: 12/07/2020] [Indexed: 12/21/2022]
Abstract
RNA interference (RNAi) technology has been used for almost two decades to study gene functions and in therapeutic approaches. It uses cellular machinery and small, designed RNAs in the form of synthetic small interfering RNAs (siRNAs) or vector-based short hairpin RNAs (shRNAs), and artificial miRNAs (amiRNAs) to inhibit a gene of interest. Artificial miRNAs, known also as miRNA mimics, shRNA-miRs, or pri-miRNA-like shRNAs have the most complex structures and undergo two-step processing in cells to form mature siRNAs, which are RNAi effectors. AmiRNAs are composed of a target-specific siRNA insert and scaffold based on a natural primary miRNA (pri-miRNA). siRNAs serve as a guide to search for complementary sequences in transcripts, whereas pri-miRNA scaffolds ensure proper processing and transport. The dynamics of siRNA maturation and siRNA levels in the cell resemble those of endogenous miRNAs; therefore amiRNAs are safer than other RNAi triggers. Delivered as viral vectors and expressed under tissue-specific polymerase II (Pol II) promoters, amiRNAs provide long-lasting silencing and expression in selected tissues. Therefore, amiRNAs are useful therapeutic tools for a broad spectrum of human diseases, including neurodegenerative diseases, cancers and viral infections. Recent reports on the role of sequence and structure in pri-miRNA processing may contribute to the improvement of the amiRNA tools. In addition, the success of a recently initiated clinical trial for Huntington's disease could pave the way for other amiRNA-based therapies, if proven effective and safe. This article is categorized under: RNA Processing > Processing of Small RNAs Regulatory RNAs/RNAi/Riboswitches > RNAi: Mechanisms of Action RNA in Disease and Development > RNA in Disease.
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Affiliation(s)
- Anna Kotowska-Zimmer
- Department of Genome Engineering, Institute of Bioorganic Chemistry PAS, Poznan, Poland
| | - Marianna Pewinska
- Department of Genome Engineering, Institute of Bioorganic Chemistry PAS, Poznan, Poland
| | - Marta Olejniczak
- Department of Genome Engineering, Institute of Bioorganic Chemistry PAS, Poznan, Poland
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22
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Current Genetic Survey and Potential Gene-Targeting Therapeutics for Neuromuscular Diseases. Int J Mol Sci 2020; 21:ijms21249589. [PMID: 33339321 PMCID: PMC7767109 DOI: 10.3390/ijms21249589] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 12/08/2020] [Accepted: 12/14/2020] [Indexed: 12/17/2022] Open
Abstract
Neuromuscular diseases (NMDs) belong to a class of functional impairments that cause dysfunctions of the motor neuron-muscle functional axis components. Inherited monogenic neuromuscular disorders encompass both muscular dystrophies and motor neuron diseases. Understanding of their causative genetic defects and pathological genetic mechanisms has led to the unprecedented clinical translation of genetic therapies. Challenged by a broad range of gene defect types, researchers have developed different approaches to tackle mutations by hijacking the cellular gene expression machinery to minimize the mutational damage and produce the functional target proteins. Such manipulations may be directed to any point of the gene expression axis, such as classical gene augmentation, modulating premature termination codon ribosomal bypass, splicing modification of pre-mRNA, etc. With the soar of the CRISPR-based gene editing systems, researchers now gravitate toward genome surgery in tackling NMDs by directly correcting the mutational defects at the genome level and expanding the scope of targetable NMDs. In this article, we will review the current development of gene therapy and focus on NMDs that are available in published reports, including Duchenne Muscular Dystrophy (DMD), Becker muscular dystrophy (BMD), X-linked myotubular myopathy (XLMTM), Spinal Muscular Atrophy (SMA), and Limb-girdle muscular dystrophy Type 2C (LGMD2C).
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23
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Rashnonejad A, Amini-Chermahini G, Taylor NK, Wein N, Harper SQ. Designed U7 snRNAs inhibit DUX4 expression and improve FSHD-associated outcomes in DUX4 overexpressing cells and FSHD patient myotubes. MOLECULAR THERAPY-NUCLEIC ACIDS 2020; 23:476-486. [PMID: 33510937 PMCID: PMC7807095 DOI: 10.1016/j.omtn.2020.12.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 12/06/2020] [Indexed: 12/21/2022]
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) arises from epigenetic changes that de-repress the DUX4 gene in muscle. The full-length DUX4 protein causes cell death and muscle toxicity, and therefore we hypothesize that FSHD therapies should center on inhibiting full-length DUX4 expression. In this study, we developed a strategy to accomplish DUX4 inhibition using U7-small nuclear RNA (snRNA) antisense expression cassettes (called U7-asDUX4). These non-coding RNAs were designed to inhibit production or maturation of the full-length DUX4 pre-mRNA by masking the DUX4 start codon, splice sites, or polyadenylation signal. In so doing, U7-asDUX4 snRNAs operate similarly to antisense oligonucleotides. However, in contrast to oligonucleotides, which are limited by poor uptake in muscle and a requirement for lifelong repeated dosing, U7-asDUX4 snRNAs can be packaged within myotropic gene therapy vectors and may require only a single administration when delivered to post-mitotic cells in vivo. We tested several U7-asDUX4s that reduced DUX4 expression in vitro and improved DUX4-associated outcomes. Inhibition of DUX4 expression via U7-snRNAs could be a new prospective gene therapy approach for FSHD or be used in combination with other strategies, like RNAi therapy, to maximize DUX4 silencing in individuals with FSHD.
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Affiliation(s)
- Afrooz Rashnonejad
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA
| | - Gholamhossein Amini-Chermahini
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA
| | - Noah K Taylor
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA
| | - Nicolas Wein
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA.,Department of Pediatrics, The Ohio State University, Columbus, OH, USA
| | - Scott Q Harper
- Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, 700 Children's Drive, Columbus, OH 43205, USA.,Department of Pediatrics, The Ohio State University, Columbus, OH, USA
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24
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DeSimone AM, Cohen J, Lek M, Lek A. Cellular and animal models for facioscapulohumeral muscular dystrophy. Dis Model Mech 2020; 13:13/10/dmm046904. [PMID: 33174531 PMCID: PMC7648604 DOI: 10.1242/dmm.046904] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is one of the most common forms of muscular dystrophy and presents with weakness of the facial, scapular and humeral muscles, which frequently progresses to the lower limbs and truncal areas, causing profound disability. Myopathy results from epigenetic de-repression of the D4Z4 microsatellite repeat array on chromosome 4, which allows misexpression of the developmentally regulated DUX4 gene. DUX4 is toxic when misexpressed in skeletal muscle and disrupts several cellular pathways, including myogenic differentiation and fusion, which likely underpins pathology. DUX4 and the D4Z4 array are strongly conserved only in primates, making FSHD modeling in non-primate animals difficult. Additionally, its cytotoxicity and unusual mosaic expression pattern further complicate the generation of in vitro and in vivo models of FSHD. However, the pressing need to develop systems to test therapeutic approaches has led to the creation of multiple engineered FSHD models. Owing to the complex genetic, epigenetic and molecular factors underlying FSHD, it is difficult to engineer a system that accurately recapitulates every aspect of the human disease. Nevertheless, the past several years have seen the development of many new disease models, each with their own associated strengths that emphasize different aspects of the disease. Here, we review the wide range of FSHD models, including several in vitro cellular models, and an array of transgenic and xenograft in vivo models, with particular attention to newly developed systems and how they are being used to deepen our understanding of FSHD pathology and to test the efficacy of drug candidates. Summary: Owing to its complex etiology and the toxicity of DUX4, modeling facioscapulohumeral muscular dystrophy (FSHD) is uniquely challenging. Here, we review the approaches that overcame these difficulties to develop highly relevant FSHD models.
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Affiliation(s)
- Alec M DeSimone
- Yale School of Medicine, Department of Genetics, New Haven, CT 06510, USA
| | - Justin Cohen
- Yale School of Medicine, Department of Genetics, New Haven, CT 06510, USA
| | - Monkol Lek
- Yale School of Medicine, Department of Genetics, New Haven, CT 06510, USA
| | - Angela Lek
- Yale School of Medicine, Department of Genetics, New Haven, CT 06510, USA
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25
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Chen TH, Wu YZ, Tseng YH. Early-Onset Infantile Facioscapulohumeral Muscular Dystrophy: A Timely Review. Int J Mol Sci 2020; 21:ijms21207783. [PMID: 33096728 PMCID: PMC7589635 DOI: 10.3390/ijms21207783] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 01/08/2023] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD)—the worldwide third most common inherited muscular dystrophy caused by the heterozygous contraction of a 3.3 kb tandem repeat (D4Z4) on a chromosome with a 4q35 haplotype—is a progressive genetic myopathy with variable onset of symptoms, distribution of muscle weakness, and clinical severity. While much is known about the clinical course of adult FSHD, data on the early-onset infantile phenotype, especially on the progression of the disease, are relatively scarce. Contrary to the classical form, patients with infantile FSHD more often have a rapid decline in muscle wasting and systemic features with multiple extramuscular involvements. A rough correlation between the phenotypic severity of FSHD and the D4Z4 repeat size has been reported, and the majority of patients with infantile FSHD obtain a very short D4Z4 repeat length (one to three copies, EcoRI size 10–14 kb), in contrast to the classical, slowly progressive, form of FSHD (15–38 kb). With the increasing identifications of case reports and the advance in genetic diagnostics, recent studies have suggested that the infantile variant of FSHD is not a genetically separate entity but a part of the FSHD spectrum. Nevertheless, many questions about the clinical phenotype and natural history of infantile FSHD remain unanswered, limiting evidence-based clinical management. In this review, we summarize the updated research to gain insight into the clinical spectrum of infantile FSHD and raise views to improve recognition and understanding of its underlying pathomechanism, and further, to advance novel treatments and standard care methods.
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Affiliation(s)
- Tai-Heng Chen
- Section of Neurobiology, Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089, USA
- Department of Pediatrics, Division of Pediatric Emergency, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- School of Post-Baccalaureate Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Yan-Zhang Wu
- Department of Pediatrics, Division of Pediatric Emergency, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Yung-Hao Tseng
- Department of Pediatrics, Division of Pediatric Emergency, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
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26
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Evaluation of blood gene expression levels in facioscapulohumeral muscular dystrophy patients. Sci Rep 2020; 10:17547. [PMID: 33067535 PMCID: PMC7567883 DOI: 10.1038/s41598-020-74687-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Accepted: 09/29/2020] [Indexed: 12/12/2022] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is caused by the expression of DUX4 in skeletal muscles. A number of therapeutic approaches are being developed to antagonize the events preceding and following DUX4 expression that leads to muscular dystrophy. Currently, the possibility to evaluate treatment response in clinical trials is hampered by the lack of objective molecular biomarkers connecting the disease cause to clinical performance. In this study we employed RNA-seq to examine gene expression in PAXgene tubes obtained from two independent cohorts of FSHD patients. Analysis of gene expression profiles did not lead to the identification of genes or pathways differentially expressed in FSHD patients, or associated with disease severity. In particular, we did not find evidence that the DUX4 and PAX7 signatures were differentially expressed. On the other hand, we were able to improve patient classification by including single genes or groups of genes in classification models. The best classifier was ROPN1L, a gene known to be expressed in testis, coincidentally the typical location of DUX4 expression. These improvements in patient classification hold the potential to enrich the FSHD clinical trial toolbox.
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27
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Bouwman LF, van der Maarel SM, de Greef JC. The prospects of targeting DUX4 in facioscapulohumeral muscular dystrophy. Curr Opin Neurol 2020; 33:635-640. [PMID: 32796277 PMCID: PMC7735392 DOI: 10.1097/wco.0000000000000849] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
PURPOSE OF REVIEW Facioscapulohumeral muscular dystrophy (FSHD) is a neuromuscular disorder, which is caused by incomplete repression of the transcription factor double homeobox 4 (DUX4) in skeletal muscle. To date, there is no DUX4-targeting treatment to prevent or delay disease progression. In the present review, we summarize developments in therapeutic strategies with the focus on inhibiting DUX4 and DUX4 target gene expression. RECENT FINDINGS Different studies show that DUX4 and its target genes can be repressed with genetic therapies using diverse strategies. Additionally, different small compounds can reduce DUX4 and its target genes in vitro and in vivo. SUMMARY Most studies that show DUX4 repression by genetic therapies have only been tested in vitro. More efforts should be made to test them in vivo for clinical translation. Several compounds have been shown to prevent DUX4 and target gene expression in vitro and in vivo. However, their efficiency and specificity has not yet been shown. With emerging clinical trials, the clinical benefit from DUX4 repression in FSHD will likely soon become apparent.
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Affiliation(s)
- Linde F Bouwman
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
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28
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Abstract
Gene-specific treatment for hereditary muscle diseases has made great progress in recent years. The pathomechanisms of many of these diseases could be decrypted using molecular genetic techniques, paving the way for disease-modifying treatment options. A milestone was undoubtedly the successful translation of the antisense oligonucleotide (ASO) technology into clinical practice, with gene-specific ASOs being approved for the first time in 2016 for the treatment of spinal muscular atrophy and Duchenne muscular dystrophy. This article reviews recent developments in the field of antisense and gene therapies for hereditary muscle diseases.
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29
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Induction of a local muscular dystrophy using electroporation in vivo: an easy tool for screening therapeutics. Sci Rep 2020; 10:11301. [PMID: 32647247 PMCID: PMC7347864 DOI: 10.1038/s41598-020-68135-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Accepted: 06/09/2020] [Indexed: 01/19/2023] Open
Abstract
Intramuscular injection and electroporation of naked plasmid DNA (IMEP) has emerged as a potential alternative to viral vector injection for transgene expression into skeletal muscles. In this study, IMEP was used to express the DUX4 gene into mouse tibialis anterior muscle. DUX4 is normally expressed in germ cells and early embryo, and silenced in adult muscle cells where its pathological reactivation leads to Facioscapulohumeral muscular dystrophy. DUX4 encodes a potent transcription factor causing a large deregulation cascade. Its high toxicity but sporadic expression constitutes major issues for testing emerging therapeutics. The IMEP method appeared as a convenient technique to locally express DUX4 in mouse muscles. Histological analyses revealed well delineated muscle lesions 1-week after DUX4 IMEP. We have therefore developed a convenient outcome measure by quantification of the damaged muscle area using color thresholding. This method was used to characterize lesion distribution and to assess plasmid recirculation and dose–response. DUX4 expression and activity were confirmed at the mRNA and protein levels and through a quantification of target gene expression. Finally, this study gives a proof of concept of IMEP model usefulness for the rapid screening of therapeutic strategies, as demonstrated using antisense oligonucleotides against DUX4 mRNA.
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30
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Rojas LA, Valentine E, Accorsi A, Maglio J, Shen N, Robertson A, Kazmirski S, Rahl P, Tawil R, Cadavid D, Thompson LA, Ronco L, Chang AN, Cacace AM, Wallace O. p38α Regulates Expression of DUX4 in a Model of Facioscapulohumeral Muscular Dystrophy. J Pharmacol Exp Ther 2020; 374:489-498. [DOI: 10.1124/jpet.119.264689] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 05/26/2020] [Indexed: 12/12/2022] Open
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31
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Morelli KH, Griffin LB, Pyne NK, Wallace LM, Fowler AM, Oprescu SN, Takase R, Wei N, Meyer-Schuman R, Mellacheruvu D, Kitzman JO, Kocen SG, Hines TJ, Spaulding EL, Lupski JR, Nesvizhskii A, Mancias P, Butler IJ, Yang XL, Hou YM, Antonellis A, Harper SQ, Burgess RW. Allele-specific RNA interference prevents neuropathy in Charcot-Marie-Tooth disease type 2D mouse models. J Clin Invest 2020; 129:5568-5583. [PMID: 31557132 DOI: 10.1172/jci130600] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Accepted: 09/10/2019] [Indexed: 12/24/2022] Open
Abstract
Gene therapy approaches are being deployed to treat recessive genetic disorders by restoring the expression of mutated genes. However, the feasibility of these approaches for dominantly inherited diseases - where treatment may require reduction in the expression of a toxic mutant protein resulting from a gain-of-function allele - is unclear. Here we show the efficacy of allele-specific RNAi as a potential therapy for Charcot-Marie-Tooth disease type 2D (CMT2D), caused by dominant mutations in glycyl-tRNA synthetase (GARS). A de novo mutation in GARS was identified in a patient with a severe peripheral neuropathy, and a mouse model precisely recreating the mutation was produced. These mice developed a neuropathy by 3-4 weeks of age, validating the pathogenicity of the mutation. RNAi sequences targeting mutant GARS mRNA, but not wild-type, were optimized and then packaged into AAV9 for in vivo delivery. This almost completely prevented the neuropathy in mice treated at birth. Delaying treatment until after disease onset showed modest benefit, though this effect decreased the longer treatment was delayed. These outcomes were reproduced in a second mouse model of CMT2D using a vector specifically targeting that allele. The effects were dose dependent, and persisted for at least 1 year. Our findings demonstrate the feasibility of AAV9-mediated allele-specific knockdown and provide proof of concept for gene therapy approaches for dominant neuromuscular diseases.
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Affiliation(s)
- Kathryn H Morelli
- The Jackson Laboratory, Bar Harbor, Maine, USA.,Graduate School of Biomedical Science and Engineering, University of Maine, Orono, Maine, USA
| | - Laurie B Griffin
- Program in Cellular and Molecular Biology, and.,Medical Scientist Training Program, University of Michigan, Ann Arbor, Michigan, USA
| | - Nettie K Pyne
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Lindsay M Wallace
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Allison M Fowler
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Stephanie N Oprescu
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, USA
| | - Ryuichi Takase
- Department of Biochemistry and Molecular Biochemistry, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Na Wei
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | | | - Dattatreya Mellacheruvu
- Department of Pathology, and.,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Jacob O Kitzman
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, USA
| | | | | | - Emily L Spaulding
- The Jackson Laboratory, Bar Harbor, Maine, USA.,Graduate School of Biomedical Science and Engineering, University of Maine, Orono, Maine, USA
| | - James R Lupski
- Department of Molecular and Human Genetics, and.,Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.,Texas Children's Hospital, Houston, Texas, USA
| | - Alexey Nesvizhskii
- Department of Pathology, and.,Department of Computational Medicine and Bioinformatics, University of Michigan, Ann Arbor, Michigan, USA
| | - Pedro Mancias
- Department of Pediatrics, McGovern Medical School, The University of Texas Health Science Center at Houston, and Children's Memorial Hermann Hospital, Houston, Texas, USA
| | - Ian J Butler
- Department of Pediatrics, McGovern Medical School, The University of Texas Health Science Center at Houston, and Children's Memorial Hermann Hospital, Houston, Texas, USA
| | - Xiang-Lei Yang
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, California, USA
| | - Ya-Ming Hou
- Department of Biochemistry and Molecular Biochemistry, Thomas Jefferson University, Philadelphia, Pennsylvania, USA
| | - Anthony Antonellis
- Program in Cellular and Molecular Biology, and.,Department of Human Genetics, University of Michigan, Ann Arbor, Michigan, USA
| | - Scott Q Harper
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Robert W Burgess
- The Jackson Laboratory, Bar Harbor, Maine, USA.,Graduate School of Biomedical Science and Engineering, University of Maine, Orono, Maine, USA
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Abstract
PURPOSE OF REVIEW Facioscapulohumeral muscular dystrophy (FSHD) is a common muscular dystrophy affecting both pediatric and adult patients. This article reviews the phenotype and pathophysiology of the disease as well as the recent efforts in clinical outcome measures and clinical trials. RECENT FINDINGS As the name implies, FSHD involves weakness of facial muscles, muscles that fix the scapula, and muscles overlying the humerus (biceps and triceps). The distinctive phenotype of FSHD occurs secondary to two different genetic mechanisms. FSHD type 1 (FSHD1) is due to a deletion on chromosome 4q, leading to hypomethylation and derepression of DUX4. FSHD type 2 (FSHD2) is due to mutations in SMCHD1 with resulting hypomethylation of the same subtelomeric region of chromosome 4q and derepression of DUX4. Understanding the central role of DUX4 has opened up the possibility of disease-modifying treatments. In preparation for clinical trials of novel agents, researchers are in the process of validating a number of clinical trial outcome measures including MRI, the 6-minute walk test, the FSHD Composite Outcome Measure, reachable workspace, electrical impedance myography, and the FSHD Health Index. SUMMARY The treatment of FSHD is currently supportive only. While past clinical trials in FSHD have been largely disappointing, novel agents in development, including antisense oligonucleotides, gene therapy, and small molecules, hold promise for future meaningful therapies.
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Abstract
Skeletal muscle fibres are multinucleated cells that contain postmitotic nuclei (i.e. they are no longer able to divide) and perform muscle contraction. They are formed by fusion of muscle precursor cells, and grow into elongating myofibres by the addition of further precursor cells, called satellite cells, which are also responsible for regeneration following injury. Skeletal muscle regeneration occurs in most muscular dystrophies in response to necrosis of muscle fibres. However, the complex environment within dystrophic skeletal muscle, which includes inflammatory cells, fibroblasts and fibro-adipogenic cells, together with the genetic background of the in vivo model and the muscle being studied, complicates the interpretation of laboratory studies on muscular dystrophies. Many genes are expressed in satellite cells and in other tissues, which makes it difficult to determine the molecular cause of various types of muscular dystrophies. Here, and in the accompanying poster, we discuss our current knowledge of the cellular mechanisms that govern the growth and regeneration of skeletal muscle, and highlight the defects in satellite cell function that give rise to muscular dystrophies. Summary: The mechanisms of skeletal muscle development, growth and regeneration are described. We discuss whether these processes are dysregulated in inherited muscle diseases and identify pathways that may represent therapeutic targets.
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Affiliation(s)
- Jennifer Morgan
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK .,National Institute for Health Research, Great Ormond Street Institute of Child Health Biomedical Research Centre, University College London, London WC1N 1EH, UK
| | - Terence Partridge
- Dubowitz Neuromuscular Centre, UCL Great Ormond Street Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK.,National Institute for Health Research, Great Ormond Street Institute of Child Health Biomedical Research Centre, University College London, London WC1N 1EH, UK.,Center for Genetic Medicine Research, Children's National Medical Center, 111 Michigan Ave NW, Washington, DC 20010, USA
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34
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26th Annual Facioscapulohumeral Dystrophy International Research Congress Marseille, France, 19-20 June 2019. Neuromuscul Disord 2019; 29:811-817. [PMID: 31604652 DOI: 10.1016/j.nmd.2019.08.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 08/28/2019] [Indexed: 11/23/2022]
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35
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Crudele JM, Chamberlain JS. AAV-based gene therapies for the muscular dystrophies. Hum Mol Genet 2019; 28:R102-R107. [PMID: 31238336 PMCID: PMC6796995 DOI: 10.1093/hmg/ddz128] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 05/21/2019] [Accepted: 06/07/2019] [Indexed: 01/22/2023] Open
Abstract
Muscular dystrophy (MD) is a group of progressive genetic diseases affecting the musculature that are characterized by inflammatory infiltrates, necrosis and connective tissue and fat replacement of the affected muscles. Unfortunately, treatments do not exist for the vast majority of MD patients. Adeno-associated viral vector (AAV)-based gene therapy is thus emerging as a potential treatment for many types of MD. Treatments strategies based on AAV are being adapted for replacement of mutant disease-causing genes, knockdown of dominant disease-causing genes using antisense oligonucleotides or inhibitory RNAs, delivery of gene editing tools such as clustered regularly interspaced short palindromic repeats/Cas9 and effecting alterations in pre-mRNA splicing and by manipulating expression levels of modifier genes. Translational and clinical trial work focused on these types of AAV treatments for Duchenne MD, various limb girdle MDs, myotonic dystrophy 1, facioscapulohumeral MD, dysferlinopathies and congenital MDs are discussed here, with a focus on recent studies, pre-clinical large animal work and many promising ongoing and upcoming AAV clinical trials.
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Affiliation(s)
- Julie M Crudele
- Department of Neurology, University of Washington, Seattle, WA, USA
- Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, WA, USA
| | - Jeffrey S Chamberlain
- Department of Neurology, University of Washington, Seattle, WA, USA
- Senator Paul D. Wellstone Muscular Dystrophy Specialized Research Center, University of Washington, Seattle, WA, USA
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36
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Amini Chermahini G, Rashnonejad A, Harper SQ. RNAscope in situ hybridization-based method for detecting DUX4 RNA expression in vitro. RNA (NEW YORK, N.Y.) 2019; 25:1211-1217. [PMID: 31209064 PMCID: PMC6800509 DOI: 10.1261/rna.070177.118] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 06/07/2019] [Indexed: 06/09/2023]
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is among the most common forms of muscular dystrophy. FSHD is caused by aberrant expression of the toxic DUX4 gene in muscle. Detecting endogenous DUX4 in patient tissue using conventional methods can be challenging, due to the low level of DUX4 expression. Therefore, developing simple and trustworthy DUX4 detection methods is an important need in the FSHD field. Here, we describe such a method, which uses the RNAscope assay, an RNA in situ hybridization (ISH) technology. We show that a custom-designed RNAscope assay can detect overexpressed DUX4 mRNA in transfected HEK293 cells and endogenous DUX4 mRNA in FSHD patient-derived myotubes. The RNAscope assay was highly sensitive for tracking reductions in DUX4 mRNA following treatment with our therapeutic mi405 microRNA, suggesting that RNAscope-based DUX4 expression assays could be developed as a prospective outcome measure in therapy trials. This study could set the stage for optimizing and developing a new, rapid RNA ISH-based molecular diagnostic assay for future clinical use in the FSHD field.
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Affiliation(s)
| | - Afrooz Rashnonejad
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio 43205, USA
| | - Scott Q Harper
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio 43205, USA
- Department of Pediatrics, The Ohio State University, Columbus, Ohio 43205, USA
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37
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[Innovative therapeutic approaches for hereditary neuromuscular diseases]. DER NERVENARZT 2019; 89:1115-1122. [PMID: 30171303 DOI: 10.1007/s00115-018-0599-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Advances in the understanding of the genetic mechanisms and pathophysiology of neuromuscular diseases have recently led to the development of new, innovative and often mutation-specific therapeutic approaches. Methods used include splicing modification by antisense oligonucleotides, read-through of premature stopcodons, use of viral vectors to introduce genetic information, or optimizing the effectiveness of enzyme replacement therapies. The first drugs have already been approved for the treatment of Duchenne muscular dystrophy and spinal muscular atrophy. For other diseases, such as myotubular myopathy, myotonic dystrophy, facioscapulohumeral muscular dystrophy and Pompe disease, new promising approaches are in preclinical or clinical development. As these are rare diseases with a broad spectrum of clinical severity, drug approval is often based on a limited amount of evidence. Therefore, systematic follow-up in the postmarketing period is particularly important to assess the safety and efficacy of these new and often high-priced orphan drugs.
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38
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Giesige CR, Wallace LM, Heller KN, Eidahl JO, Saad NY, Fowler AM, Pyne NK, Al-Kharsan M, Rashnonejad A, Chermahini GA, Domire JS, Mukweyi D, Garwick-Coppens SE, Guckes SM, McLaughlin KJ, Meyer K, Rodino-Klapac LR, Harper SQ. AAV-mediated follistatin gene therapy improves functional outcomes in the TIC-DUX4 mouse model of FSHD. JCI Insight 2018; 3:123538. [PMID: 30429376 DOI: 10.1172/jci.insight.123538] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2018] [Accepted: 10/10/2018] [Indexed: 01/08/2023] Open
Abstract
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant or digenic disorder linked to derepression of the toxic DUX4 gene in muscle. There is currently no pharmacological treatment. The emergence of DUX4 enabled development of cell and animal models that could be used for basic and translational research. Since DUX4 is toxic, animal model development has been challenging, but progress has been made, revealing that tight regulation of DUX4 expression is critical for creating viable animals that develop myopathy. Here, we report such a model - the tamoxifen-inducible FSHD mouse model called TIC-DUX4. Uninduced animals are viable, born in Mendelian ratios, and overtly indistinguishable from WT animals. Induced animals display significant DUX4-dependent myopathic phenotypes at the molecular, histological, and functional levels. To demonstrate the utility of TIC-DUX4 mice for therapeutic development, we tested a gene therapy approach aimed at improving muscle strength in DUX4-expressing muscles using adeno-associated virus serotype 1.Follistatin (AAV1.Follistatin), a natural myostatin antagonist. This strategy was not designed to modulate DUX4 but could offer a mechanism to improve muscle weakness caused by DUX4-induced damage. AAV1.Follistatin significantly increased TIC-DUX4 muscle mass and strength even in the presence of DUX4 expression, suggesting that myostatin inhibition may be a promising approach to treat FSHD-associated weakness. We conclude that TIC-DUX4 mice are a relevant model to study DUX4 toxicity and, importantly, are useful in therapeutic development studies for FSHD.
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Affiliation(s)
- Carlee R Giesige
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, Ohio, USA.,Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Lindsay M Wallace
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Kristin N Heller
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Jocelyn O Eidahl
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Nizar Y Saad
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Allison M Fowler
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Nettie K Pyne
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Mustafa Al-Kharsan
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Afrooz Rashnonejad
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | | | - Jacqueline S Domire
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Diana Mukweyi
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Sara E Garwick-Coppens
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Susan M Guckes
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - K John McLaughlin
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
| | - Kathrin Meyer
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA
| | - Louise R Rodino-Klapac
- Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
| | - Scott Q Harper
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, Ohio, USA.,Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, Ohio, USA.,Department of Pediatrics, The Ohio State University, Columbus, Ohio, USA
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Hamel J, Tawil R. Facioscapulohumeral Muscular Dystrophy: Update on Pathogenesis and Future Treatments. Neurotherapeutics 2018; 15:863-871. [PMID: 30361930 PMCID: PMC6277282 DOI: 10.1007/s13311-018-00675-3] [Citation(s) in RCA: 60] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
A reliable model of a disease pathomechanism is the first step to develop targeted treatment. In facioscapulohumeral muscular dystrophy (FSHD), the third most common muscular dystrophy, recent advances in understanding the complex genetics and epigenetics have led to the identification of a disease mechanism, moving the field towards targeted therapy development. FSHD is caused by expression of DUX4, a retrogene located on the D4Z4 macrosatellite repeat array on chromosome 4q35, a gene expressed in the germline but typically repressed in somatic tissue. DUX4 derepression results from opening of the chromatin structure either by contraction of the number of repeats (FSHD1) or by chromatin hypomethylation of the D4Z4 repeats resulting from mutations in SMCHD1, a gene involved in chromatin methylation (FSHD2). The resulting expression of DUX4, a transcriptional regulator, and its target genes is toxic to skeletal muscle. Efforts for targeted treatment currently focus on disrupting DUX4 expression or blocking 1 or more of several downstream effects of DUX4. This review article focuses on the underlying FSHD genetics, current understanding of the pathomechanism, and potential treatment strategies in FSHD. In addition, recent advances in the development of new clinical outcome measures as well as biomarkers, critical for the success of future clinical trials, are reviewed.
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Affiliation(s)
- Johanna Hamel
- Department of Neurology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 673, Rochester, NY, 14642, USA.
| | - Rabi Tawil
- Department of Neurology, University of Rochester Medical Center, 601 Elmwood Avenue, Box 673, Rochester, NY, 14642, USA
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Abstract
PURPOSE OF REVIEW To construct a framework to understand the different molecular interventions for muscular dystrophy. RECENT FINDINGS The recent approval of antisense oligonucleotides treatment for Duchenne muscular dystrophy and spinal muscular atrophy and current clinical trials using recombinant adeno-associated virus for the treatment of those diseases suggests that we are at a tipping point where we are able to treat and potentially cure muscular dystrophies. Understanding the basic molecular pathogenesis of muscular dystrophies and the molecular biology of the treatment allows for critical evaluation of the proposed therapies.
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Affiliation(s)
- Ava Y Lin
- Department of Neurology, University of Washington, Box 356465, 1959 NE Pacific Street, Seattle, WA, 98195-6465, USA
| | - Leo H Wang
- Department of Neurology, University of Washington, Box 356465, 1959 NE Pacific Street, Seattle, WA, 98195-6465, USA.
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Mitsuhashi H, Ishimaru S, Homma S, Yu B, Honma Y, Beermann ML, Miller JB. Functional domains of the FSHD-associated DUX4 protein. Biol Open 2018; 7:bio.033977. [PMID: 29618456 PMCID: PMC5936065 DOI: 10.1242/bio.033977] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Aberrant expression of the full-length isoform of DUX4 (DUX4-FL) appears to underlie pathogenesis in facioscapulohumeral muscular dystrophy (FSHD). DUX4-FL is a transcription factor and ectopic expression of DUX4-FL is toxic to most cells. Previous studies showed that DUX4-FL-induced pathology requires intact homeodomains and that transcriptional activation required the C-terminal region. In this study, we further examined the functional domains of DUX4 by generating mutant, deletion, and fusion variants of DUX4. We compared each construct to DUX4-FL for (i) activation of a DUX4 promoter reporter, (ii) expression of the DUX4-FL target gene ZSCAN4, (iii) effect on cell viability, (iv) activation of endogenous caspases, and (v) level of protein ubiquitination. Each construct produced a similarly sized effect (or lack of effect) in each assay. Thus, the ability to activate transcription determined the extent of change in multiple molecular and cellular properties that may be relevant to FSHD pathology. Transcriptional activity was mediated by the C-terminal 80 amino acids of DUX4-FL, with most activity located in the C-terminal 20 amino acids. We also found that non-toxic constructs with both homeodomains intact could act as inhibitors of DUX4-FL transcriptional activation, likely due to competition for promoter sites. This article has an associated First Person interview with the first author of the paper. Summary: Aberrant expression of DUX4 underlies facioscapulohumeral muscular dystrophy. This study identified functional domains of DUX4 and demonstrated that multiple pathological changes are related to DUX4-mediated transcriptional activation.
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Affiliation(s)
- Hiroaki Mitsuhashi
- Department of Applied Biochemistry, School of Engineering, Tokai University, Kanagawa 259-1207, Japan
| | - Satoshi Ishimaru
- Department of Applied Biochemistry, School of Engineering, Tokai University, Kanagawa 259-1207, Japan
| | - Sachiko Homma
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Bryant Yu
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Yuki Honma
- Department of Applied Biochemistry, School of Engineering, Tokai University, Kanagawa 259-1207, Japan
| | - Mary Lou Beermann
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - Jeffrey Boone Miller
- Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
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