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Na B, Shah SR, Vasudevan HN. Past, Present, and Future Therapeutic Strategies for NF-1-Associated Tumors. Curr Oncol Rep 2024; 26:706-713. [PMID: 38709422 PMCID: PMC11169015 DOI: 10.1007/s11912-024-01527-4] [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] [Accepted: 03/27/2024] [Indexed: 05/07/2024]
Abstract
PURPOSE OF REVIEW Neurofibromatosis type 1 (NF-1) is a cancer predisposition syndrome caused by mutations in the NF1 tumor suppressor gene that encodes the neurofibromin protein, which functions as a negative regulator of Ras signaling. We review the past, current, and future state of therapeutic strategies for tumors associated with NF-1. RECENT FINDINGS Therapeutic efforts for NF-1-associated tumors have centered around inhibiting Ras output, leading to the clinical success of downstream MEK inhibition for plexiform neurofibromas and low-grade gliomas. However, MEK inhibition and similar molecular monotherapy approaches that block Ras signaling do not work for all patients and show limited efficacy for more aggressive cancers such as malignant peripheral nerve sheath tumors and high-grade gliomas, motivating novel treatment approaches. We highlight the current therapeutic landscape for NF-1-associated tumors, broadly categorizing treatment into past strategies for serial Ras pathway blockade, current approaches targeting parallel oncogenic and tumor suppressor pathways, and future avenues of investigation leveraging biologic and technical innovations in immunotherapy, pharmacology, and gene delivery.
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Affiliation(s)
- Brian Na
- Department of Neurology, UCLA Neuro-Oncology Program, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Shilp R Shah
- Samueli School of Engineering, University of California Los Angeles, Los Angeles, CA, 90095, USA
| | - Harish N Vasudevan
- Department of Radiation Oncology, University of California San Francisco, San Francisco, CA, 94143, USA.
- Department of Neurological Surgery, University of California San Francisco, San Francisco, CA, 94143, USA.
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Staedtke V, Anstett K, Bedwell D, Giovannini M, Keeling K, Kesterson R, Kim Y, Korf B, Leier A, McManus ML, Sarnoff H, Vitte J, Walker JA, Plotkin SR, Wallis D. Gene-targeted therapy for neurofibromatosis and schwannomatosis: The path to clinical trials. Clin Trials 2024; 21:51-66. [PMID: 37937606 DOI: 10.1177/17407745231207970] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2023]
Abstract
Numerous successful gene-targeted therapies are arising for the treatment of a variety of rare diseases. At the same time, current treatment options for neurofibromatosis 1 and schwannomatosis are limited and do not directly address loss of gene/protein function. In addition, treatments have mostly focused on symptomatic tumors, but have failed to address multisystem involvement in these conditions. Gene-targeted therapies hold promise to address these limitations. However, despite intense interest over decades, multiple preclinical and clinical issues need to be resolved before they become a reality. The optimal approaches to gene-, mRNA-, or protein restoration and to delivery to the appropriate cell types remain elusive. Preclinical models that recapitulate manifestations of neurofibromatosis 1 and schwannomatosis need to be refined. The development of validated assays for measuring neurofibromin and merlin activity in animal and human tissues will be critical for early-stage trials, as will the selection of appropriate patients, based on their individual genotypes and risk/benefit balance. Once the safety of gene-targeted therapy for symptomatic tumors has been established, the possibility of addressing a wide range of symptoms, including non-tumor manifestations, should be explored. As preclinical efforts are underway, it will be essential to educate both clinicians and those affected by neurofibromatosis 1/schwannomatosis about the risks and benefits of gene-targeted therapy for these conditions.
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Affiliation(s)
- Verena Staedtke
- Department of Neurology, Johns Hopkins University, Baltimore, MD, USA
| | - Kara Anstett
- Department of Neurology, NYU Grossman School of Medicine, New York, NY, USA
| | - David Bedwell
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Marco Giovannini
- Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA and Jonsson Comprehensive Cancer Center (JCCC), University of California Los Angeles, Los Angeles, CA, USA
| | - Kim Keeling
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, AL, USA
| | - Robert Kesterson
- Department of Cancer Precision Medicine, Pennington Biomedical Research Center, Baton Rouge, LA, USA
| | - YooRi Kim
- Gilbert Family Foundation, Detroit, MI, USA
| | - Bruce Korf
- Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL, USA
| | - André Leier
- Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL, USA
| | | | | | - Jeremie Vitte
- Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA and Jonsson Comprehensive Cancer Center (JCCC), University of California Los Angeles, Los Angeles, CA, USA
| | - James A Walker
- Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Scott R Plotkin
- Department of Neurology and Cancer Center, Massachusetts General Hospital, Boston, MA, USA
| | - Deeann Wallis
- Department of Genetics, The University of Alabama at Birmingham, Birmingham, AL, USA
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Báez-Flores J, Rodríguez-Martín M, Lacal J. The therapeutic potential of neurofibromin signaling pathways and binding partners. Commun Biol 2023; 6:436. [PMID: 37081086 PMCID: PMC10119308 DOI: 10.1038/s42003-023-04815-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 04/05/2023] [Indexed: 04/22/2023] Open
Abstract
Neurofibromin controls many cell processes, such as growth, learning, and memory. If neurofibromin is not working properly, it can lead to health problems, including issues with the nervous, skeletal, and cardiovascular systems and cancer. This review examines neurofibromin's binding partners, signaling pathways and potential therapeutic targets. In addition, it summarizes the different post-translational modifications that can affect neurofibromin's interactions with other molecules. It is essential to investigate the molecular mechanisms that underlie neurofibromin variants in order to provide with functional connections between neurofibromin and its associated proteins for possible therapeutic targets based on its biological function.
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Affiliation(s)
- Juan Báez-Flores
- Laboratory of Functional Genetics of Rare Diseases, Department of Microbiology and Genetics, University of Salamanca (USAL), 37007, Salamanca, Spain
- Institute of Biomedical Research of Salamanca (IBSAL), 37007, Salamanca, Spain
| | - Mario Rodríguez-Martín
- Laboratory of Functional Genetics of Rare Diseases, Department of Microbiology and Genetics, University of Salamanca (USAL), 37007, Salamanca, Spain
- Institute of Biomedical Research of Salamanca (IBSAL), 37007, Salamanca, Spain
| | - Jesus Lacal
- Laboratory of Functional Genetics of Rare Diseases, Department of Microbiology and Genetics, University of Salamanca (USAL), 37007, Salamanca, Spain.
- Institute of Biomedical Research of Salamanca (IBSAL), 37007, Salamanca, Spain.
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A High-Throughput Assay for In Vitro Determination of Release Factor-Dependent Peptide Release from a Pretermination Complex by Fluorescence Anisotropy-Application to Nonsense Suppressor Screening and Mechanistic Studies. Biomolecules 2023; 13:biom13020242. [PMID: 36830611 PMCID: PMC9953321 DOI: 10.3390/biom13020242] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 02/03/2023] Open
Abstract
Premature termination codons (PTCs) account for ~12% of all human disease mutations. Translation readthrough-inducing drugs (TRIDs) are prominent among the several therapeutic approaches being used to overcome PTCs. Ataluren is the only TRID that has been approved for treating patients suffering from a PTC disease, Duchenne muscular dystrophy, but it gives variable readthrough results in cells isolated from patients suffering from other PTC diseases. We recently elucidated ataluren's mechanism of action as a competitive inhibitor of release factor complex (RFC) catalysis of premature termination and identified ataluren's binding sites on the ribosome responsible for such an inhibition. These results suggest the possibility of discovering new TRIDs, which would retain ataluren's low toxicity while displaying greater potency and generality in stimulating readthrough via the inhibition of termination. Here we present a detailed description of a new in vitro plate reader assay that we are using both to screen small compound libraries for the inhibition of RFC-dependent peptide release and to better understand the influence of termination codon identity and sequence context on RFC activity.
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Functional restoration of mouse Nf1 nonsense alleles in differentiated cultured neurons. J Hum Genet 2022; 67:661-668. [PMID: 35945271 DOI: 10.1038/s10038-022-01072-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/27/2022] [Accepted: 07/27/2022] [Indexed: 11/09/2022]
Abstract
Neurofibromatosis type 1 (NF1), one of the most common autosomal dominant genetic disorders, is caused by mutations in the NF1 gene. NF1 patients have a wide variety of manifestations with a subset at high risk for the development of tumors in the central nervous system (CNS). Nonsense mutations that result in the synthesis of truncated NF1 protein (neurofibromin) are strongly associated with CNS tumors. Therapeutic nonsense suppression with small molecule drugs is a potentially powerful approach to restore the expression of genes harboring nonsense mutations. Ataluren is one such drug that has been shown to restore full-length functional protein in several models of nonsense mutation diseases, as well as in patients with nonsense mutation Duchenne muscular dystrophy. To test ataluren's potential applicability to NF1 nonsense mutations associated with CNS tumors, we generated a homozygous Nf1R683X/R683X-3X-FLAG mouse embryonic stem (mES) cell line which recapitulates an NF1 patient nonsense mutation (c.2041 C > T; p.Arg681X). We differentiated Nf1R683X/R683X-3X-FLAG mES cells into cortical neurons in vitro, treated the cells with ataluren, and demonstrated that ataluren can promote readthrough of the nonsense mutation at codon 683 of Nf1 mRNA in neural cells. The resulting full-length protein is able to reduce the cellular level of hyperactive phosphorylated ERK (pERK), a RAS effector normally suppressed by the NF1 protein.
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He Q, Jiang J, Yang J, Zeng J, Zhang H, Zhang Z. A novel mutation of the NF1 gene in a Chinese family with neurofibromatosis type 1. Am J Transl Res 2022; 14:5139-5145. [PMID: 35958499 PMCID: PMC9360891] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 06/22/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND Mutations in the neurofibromin 1 (NF1) gene are associated with clinical manifestations of neurofibromatosis type 1 (NF1). OBJECTIVE To clarify the relationship between NF1 variants and disease phenotype. METHODS Peripheral blood samples were collected from a patient and her relatives and genomic DNA was extracted for next-generation sequencing (NGS) to detect potential variants; the results were validated by Sanger sequencing. RESULTS A novel frameshift variant c.4508_c.4509delAT (p.Asn1503fsTer26) was detected in exon 34 of the NF1 gene in the patient and her daughter, but not in any other (healthy) family member. This c.4508_c.4509delAT (p.Asn1503fsTer26) frameshift variant of NF1 may underlie NF1 in this family. CONCLUSIONS This finding expands the spectrum of pathogenic mutations of the NF1 gene, which could aid genetic counseling and prenatal diagnosis.
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Affiliation(s)
- Qi He
- Department of Dermatology, Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000, Sichuan, China
| | - Jingjing Jiang
- Department of Dermatology, Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000, Sichuan, China
| | - Jiao Yang
- Department of Dermatology, Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000, Sichuan, China
| | - Junjie Zeng
- Department of Dermatology, Taikang Sichuan Southwest Hospital Company LimitedChengdu 610000, Sichuan, China
| | - Huan Zhang
- Department of Dermatology, Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000, Sichuan, China
| | - Zhengzhong Zhang
- Department of Dermatology, Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000, Sichuan, China
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7
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CRISPR-Cas9-generated mouse model of neurofibromatosis type 1. Mol Cell Toxicol 2022. [DOI: 10.1007/s13273-022-00256-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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8
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Huang S, Bhattacharya A, Ghelfi MD, Li H, Fritsch C, Chenoweth DM, Goldman YE, Cooperman BS. Ataluren binds to multiple protein synthesis apparatus sites and competitively inhibits release factor-dependent termination. Nat Commun 2022; 13:2413. [PMID: 35523781 PMCID: PMC9076611 DOI: 10.1038/s41467-022-30080-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2021] [Accepted: 04/12/2022] [Indexed: 12/15/2022] Open
Abstract
Genetic diseases are often caused by nonsense mutations, but only one TRID (translation readthrough inducing drug), ataluren, has been approved for clinical use. Ataluren inhibits release factor complex (RFC) termination activity, while not affecting productive binding of near-cognate ternary complex (TC, aa-tRNA.eEF1A.GTP). Here we use photoaffinity labeling to identify two sites of ataluren binding within rRNA, proximal to the decoding center (DC) and the peptidyl transfer center (PTC) of the ribosome, which are directly responsible for ataluren inhibition of termination activity. A third site, within the RFC, has as yet unclear functional consequences. Using single molecule and ensemble fluorescence assays we also demonstrate that termination proceeds via rapid RFC-dependent hydrolysis of peptidyl-tRNA followed by slow release of peptide and tRNA from the ribosome. Ataluren is an apparent competitive inhibitor of productive RFC binding, acting at or before the hydrolysis step. We propose that designing more potent TRIDs which retain ataluren's low toxicity should target areas of the RFC binding site proximal to the DC and PTC which do not overlap the TC binding site.
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Affiliation(s)
- Shijie Huang
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
- GSK, 14200 Shady Grove Rd, Rockville, MD, 20850, USA
| | - Arpan Bhattacharya
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Mikel D Ghelfi
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Hong Li
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Clark Fritsch
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - David M Chenoweth
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Yale E Goldman
- Department of Physiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Barry S Cooperman
- Department of Chemistry, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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9
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Yu J, Tang B, He X, Zou P, Zeng Z, Xiao R. Nonsense Suppression Therapy: An Emerging Treatment for Hereditary Skin Diseases. Acta Derm Venereol 2022; 102:adv00658. [DOI: 10.2340/actadv.v102.353] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Nonsense mutations cause the premature termination of protein translation via premature termination codons (PTCs), leading to the synthesis of incomplete functional proteins and causing large numbers of genetic disorders. The emergence of nonsense suppression therapy is considered to be an effective method for the treatment of hereditary diseases, but its application in hereditary skin diseases is relatively limited. This review summarizes the current research status of nonsense suppression therapy for hereditary skin diseases, and discusses the potential opportunities and challenges of applying new technologies related to nonsense suppression therapy to dermatology. Further research is needed into the possible use of nonsense suppression therapy as a strategy for the safer and specific treatment of hereditary skin diseases.
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10
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Hadfield MJ, Turshudzhyan A, Grant-Kels JM. Evolving treatments and future therapeutic targets in desmoplastic melanoma. Melanoma Manag 2021; 8:MMT56. [PMID: 34900219 PMCID: PMC8656346 DOI: 10.2217/mmt-2020-0013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Accepted: 03/30/2021] [Indexed: 11/21/2022] Open
Affiliation(s)
- Matthew J Hadfield
- Department of Internal Medicine (Oncology Division), University of Connecticut Health Center, Farmington, CT 06032, USA
| | - Alla Turshudzhyan
- Department of Internal Medicine (Oncology Division), University of Connecticut Health Center, Farmington, CT 06032, USA
| | - Jane M Grant-Kels
- Department of Dermatology, University of Connecticut Health Center, Farmington, CT 06032, USA
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11
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Awad EK, Moore M, Liu H, Ciszewski L, Lambert L, Korf BR, Popplewell L, Kesterson RA, Wallis D. Restoration of Normal NF1 Function with Antisense Morpholino Treatment of Recurrent Pathogenic Patient-Specific Variant c.1466A>G; p.Y489C. J Pers Med 2021; 11:jpm11121320. [PMID: 34945792 PMCID: PMC8705852 DOI: 10.3390/jpm11121320] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Revised: 11/04/2021] [Accepted: 11/19/2021] [Indexed: 12/11/2022] Open
Abstract
Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder with almost 3000 different disease-causing variants within the NF1 gene identified. Up to 44% of these variants cause splicing errors to occur within pre-mRNA. A recurrent variant in exon 13, c.1466A>G; p.Y489C (Y489C) results in the creation of an intragenic cryptic splice site, aberrant splicing, a 62 base pair deletion from the mRNA, and subsequent frameshift. We investigated the ability of phosphorodiamidate morpholino oligomers (PMOs) to mask this variant on the RNA level, thus restoring normal splicing. To model this variant, we have developed a human iPS cell line homozygous for the variant using CRISPR/Cas9. PMOs were designed to be 25 base pairs long, and to cover the mutation site so it could not be read by splicing machinery. Results from our in vitro testing showed restoration of normal splicing in the RNA and restoration of full length neurofibromin protein. In addition, we observe the restoration of neurofibromin functionality through GTP-Ras and pERK/ERK testing. The results from this study demonstrate the ability of a PMO to correct splicing errors in NF1 variants at the RNA level, which could open the door for splicing corrections for other variants in this and a variety of diseases.
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Affiliation(s)
- Elias K. Awad
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (E.K.A.); (H.L.); (L.L.); (B.R.K.); (R.A.K.)
| | - Marc Moore
- Centre of Biomedical Sciences, Department of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK; (M.M.); (L.C.); (L.P.)
| | - Hui Liu
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (E.K.A.); (H.L.); (L.L.); (B.R.K.); (R.A.K.)
| | - Lukasz Ciszewski
- Centre of Biomedical Sciences, Department of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK; (M.M.); (L.C.); (L.P.)
| | - Laura Lambert
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (E.K.A.); (H.L.); (L.L.); (B.R.K.); (R.A.K.)
| | - Bruce R. Korf
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (E.K.A.); (H.L.); (L.L.); (B.R.K.); (R.A.K.)
| | - Linda Popplewell
- Centre of Biomedical Sciences, Department of Biological Sciences, Royal Holloway, University of London, Egham, Surrey TW20 0EX, UK; (M.M.); (L.C.); (L.P.)
| | - Robert A. Kesterson
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (E.K.A.); (H.L.); (L.L.); (B.R.K.); (R.A.K.)
| | - Deeann Wallis
- Department of Genetics, University of Alabama at Birmingham, Birmingham, AL 35294, USA; (E.K.A.); (H.L.); (L.L.); (B.R.K.); (R.A.K.)
- Correspondence: ; Tel.: +1-205-934-2794; Fax: +1-205-975-4418
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12
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Long A, Liu H, Liu J, Daniel M, Bedwell DM, Korf B, Kesterson RA, Wallis D. Analysis of patient-specific NF1 variants leads to functional insights for Ras signaling that can impact personalized medicine. Hum Mutat 2021; 43:30-41. [PMID: 34694046 DOI: 10.1002/humu.24290] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 10/13/2021] [Accepted: 10/19/2021] [Indexed: 01/04/2023]
Abstract
We have created a panel of 29 NF1 variant complementary DNAs (cDNAs) representing missense variants, many with clinically relevant phenotypes, in-frame deletions, splice variants, and nonsense variants. We have determined the functional consequences of the variants, assessing their ability to produce mature neurofibromin and restore Ras signaling activity in NF1 null (-/-) cells. cDNAs demonstrate variant-specific differences in neurofibromin protein levels, suggesting that some variants lead to neurofibromatosis type 1 (NF1) gene or protein instability or enhanced degradation. When expressed at high levels, some variant proteins are still able to repress Ras activity, indicating that the NF1 phenotype may be due to low protein abundance. In contrast, other variant proteins are incapable of repressing Ras activity, indicating that some do not functionally engage Ras and stimulate GTPase activity. We observed that effects on protein abundance and Ras activity can be mutually exclusive. These assays allow us to categorize variants by functional effects, may help to classify variants of unknown significance, and may have future implications for more directed therapeutics.
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Affiliation(s)
- Ashlee Long
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Hui Liu
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jian Liu
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Michael Daniel
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - David M Bedwell
- Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Bruce Korf
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Robert A Kesterson
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Deeann Wallis
- Department of Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA
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13
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Ataluren and aminoglycosides stimulate read-through of nonsense codons by orthogonal mechanisms. Proc Natl Acad Sci U S A 2021; 118:2020599118. [PMID: 33414181 PMCID: PMC7812769 DOI: 10.1073/pnas.2020599118] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Nonsense mutations giving rise to premature stop codons (PSCs) cause many diseases, creating the need to develop safe and effective translational read-through–inducing drugs (TRIDs). The current best-characterized TRIDs are ataluren and aminoglycosides. Only ataluren has been approved for clinical use, albeit in a limited context. Here, we provide rate measurements of elementary steps in a single eukaryotic translation elongation cycle, allowing us to demonstrate that ataluren and the aminoglycoside G418 employ orthogonal mechanisms in stimulating PSC read-through: ataluren by inhibiting release factor-dependent termination of protein synthesis and G418 by increasing functional near-cognate transfer RNA mispairing, which permits continuation of synthesis. We conclude that development of new TRIDs combatting PSC diseases should prioritize those directed toward inhibiting termination. During protein synthesis, nonsense mutations, resulting in premature stop codons (PSCs), produce truncated, inactive protein products. Such defective gene products give rise to many diseases, including cystic fibrosis, Duchenne muscular dystrophy (DMD), and some cancers. Small molecule nonsense suppressors, known as TRIDs (translational read-through–inducing drugs), stimulate stop codon read-through. The best characterized TRIDs are ataluren, which has been approved by the European Medicines Agency for the treatment of DMD, and G418, a structurally dissimilar aminoglycoside. Previously [1], we applied a highly purified in vitro eukaryotic translation system to demonstrate that both aminoglycosides like G418 and more hydrophobic molecules like ataluren stimulate read-through by direct interaction with the cell’s protein synthesis machinery. Our results suggested that they might do so by different mechanisms. Here, we pursue this suggestion through a more-detailed investigation of ataluren and G418 effects on read-through. We find that ataluren stimulation of read-through derives exclusively from its ability to inhibit release factor activity. In contrast, G418 increases functional near-cognate tRNA mispairing with a PSC, resulting from binding to its tight site on the ribosome, with little if any effect on release factor activity. The low toxicity of ataluren suggests that development of new TRIDs exclusively directed toward inhibiting termination should be a priority in combatting PSC diseases. Our results also provide rate measurements of some of the elementary steps during the eukaryotic translation elongation cycle, allowing us to determine how these rates are modified when cognate tRNA is replaced by near-cognate tRNA ± TRIDs.
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Kim Y, Varn FS, Park SH, Yoon BW, Park HR, Lee C, Verhaak RGW, Paek SH. Perspective of mesenchymal transformation in glioblastoma. Acta Neuropathol Commun 2021; 9:50. [PMID: 33762019 PMCID: PMC7992784 DOI: 10.1186/s40478-021-01151-4] [Citation(s) in RCA: 60] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 03/06/2021] [Indexed: 12/20/2022] Open
Abstract
Despite aggressive multimodal treatment, glioblastoma (GBM), a grade IV primary brain tumor, still portends a poor prognosis with a median overall survival of 12–16 months. The complexity of GBM treatment mainly lies in the inter- and intra-tumoral heterogeneity, which largely contributes to the treatment-refractory and recurrent nature of GBM. By paving the road towards the development of personalized medicine for GBM patients, the cancer genome atlas classification scheme of GBM into distinct transcriptional subtypes has been considered an invaluable approach to overcoming this heterogeneity. Among the identified transcriptional subtypes, the mesenchymal subtype has been found associated with more aggressive, invasive, angiogenic, hypoxic, necrotic, inflammatory, and multitherapy-resistant features than other transcriptional subtypes. Accordingly, mesenchymal GBM patients were found to exhibit worse prognosis than other subtypes when patients with high transcriptional heterogeneity were excluded. Furthermore, identification of the master mesenchymal regulators and their downstream signaling pathways has not only increased our understanding of the complex regulatory transcriptional networks of mesenchymal GBM, but also has generated a list of potent inhibitors for clinical trials. Importantly, the mesenchymal transition of GBM has been found to be tightly associated with treatment-induced phenotypic changes in recurrence. Together, these findings indicate that elucidating the governing and plastic transcriptomic natures of mesenchymal GBM is critical in order to develop novel and selective therapeutic strategies that can improve both patient care and clinical outcomes. Thus, the focus of our review will be on the recent advances in the understanding of the transcriptome of mesenchymal GBM and discuss microenvironmental, metabolic, and treatment-related factors as critical components through which the mesenchymal signature may be acquired. We also take into consideration the transcriptomic plasticity of GBM to discuss the future perspectives in employing selective therapeutic strategies against mesenchymal GBM.
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Galvin R, Watson AL, Largaespada DA, Ratner N, Osum S, Moertel CL. Neurofibromatosis in the Era of Precision Medicine: Development of MEK Inhibitors and Recent Successes with Selumetinib. Curr Oncol Rep 2021; 23:45. [PMID: 33721151 DOI: 10.1007/s11912-021-01032-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/18/2021] [Indexed: 02/02/2023]
Abstract
PURPOSE OF REVIEW Patients with neurofibromatosis type 1 (NF1) are at increased risk for benign and malignant neoplasms. Recently, targeted therapy with the MEK inhibitor class has helped address these needs. We highlight recent successes with selumetinib while acknowledging ongoing challenges for NF1 patients and future directions. RECENT FINDINGS MEK inhibitors have demonstrated efficacy for NF1-related conditions, including plexiform neurofibromas and low-grade gliomas, two common causes of NF1-related morbidity. Active investigations for NF1-related neoplasms have benefited from advanced understanding of the genomic and cell signaling alterations in these conditions and development of sound preclinical animal models. Selumetinib has become the first FDA-approved targeted therapy for NF1 following its demonstrated efficacy for inoperable plexiform neurofibroma. Investigations of combination therapy and the development of a representative NF1 swine model hold promise for translating therapies for other NF1-associated pathology.
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Affiliation(s)
- Robert Galvin
- Divisions of Pediatric Hematology & Oncology and Bone Marrow Transplant, University of Minnesota, Minneapolis, MN, USA
| | | | - David A Largaespada
- Division of Pediatric Hematology & Oncology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Nancy Ratner
- Cincinnati Children's Hospital Division of Exp. Hematology and Cancer Biology, Department of Pediatrics, University of Cincinnati, Cincinnati, OH, USA
| | - Sara Osum
- Division of Pediatric Hematology & Oncology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN, USA
| | - Christopher L Moertel
- Division of Pediatric Hematology & Oncology, University of Minnesota, Minneapolis, MN, USA.
- Pediatric Hematology MMC 484 Mayo, 8484B (Campus Delivery Code), 420 Delaware St SE, Minneapolis, MN, 55455, USA.
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Dönmüş B, Ünal S, Kirmizitaş FC, Türkoğlu Laçin N. Virus-associated ribozymes and nano carriers against COVID-19. ARTIFICIAL CELLS NANOMEDICINE AND BIOTECHNOLOGY 2021; 49:204-218. [PMID: 33645342 DOI: 10.1080/21691401.2021.1890103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a zoo tonic, highly pathogenic virus. The new type of coronavirus with contagious nature spread from Wuhan (China) to the whole world in a very short time and caused the new coronavirus disease (COVID-19). COVID-19 has turned into a global public health crisis due to spreading by close person-to-person contact with high transmission capacity. Thus, research about the treatment of the damages caused by the virus or prevention from infection increases everyday. Besides, there is still no approved and definitive, standardized treatment for COVID-19. However, this disaster experienced by human beings has made us realize the significance of having a system ready for use to prevent humanity from viral attacks without wasting time. As is known, nanocarriers can be targeted to the desired cells in vitro and in vivo. The nano-carrier system targeting a specific protein, containing the enzyme inhibiting the action of the virus can be developed. The system can be used by simple modifications when we encounter another virus epidemic in the future. In this review, we present a potential treatment method consisting of a nanoparticle-ribozyme conjugate, targeting ACE-2 receptors by reviewing the virus-associated ribozymes, their structures, types and working mechanisms.
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Affiliation(s)
- Beyza Dönmüş
- Molecular Biology and Genetics Department, Yıldız Technical University, Istanbul, Turkey
| | - Sinan Ünal
- Molecular Biology and Genetics Department, Yıldız Technical University, Istanbul, Turkey
| | - Fatma Ceren Kirmizitaş
- Molecular Biology and Genetics Department, Yıldız Technical University, Istanbul, Turkey
| | - Nelisa Türkoğlu Laçin
- Molecular Biology and Genetics Department, Yıldız Technical University, Istanbul, Turkey
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Riccardi C, Perrone L, Napolitano F, Sampaolo S, Melone MAB. Understanding the Biological Activities of Vitamin D in Type 1 Neurofibromatosis: New Insights into Disease Pathogenesis and Therapeutic Design. Cancers (Basel) 2020; 12:E2965. [PMID: 33066259 PMCID: PMC7602022 DOI: 10.3390/cancers12102965] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Revised: 09/18/2020] [Accepted: 10/08/2020] [Indexed: 02/07/2023] Open
Abstract
Vitamin D is a fat-soluble steroid hormone playing a pivotal role in calcium and phosphate homeostasis as well as in bone health. Vitamin D levels are not exclusively dependent on food intake. Indeed, the endogenous production-occurring in the skin and dependent on sun exposure-contributes to the majority amount of vitamin D present in the body. Since vitamin D receptors (VDRs) are ubiquitous and drive the expression of hundreds of genes, the interest in vitamin D has tremendously grown and its role in different diseases has been extensively studied. Several investigations indicated that vitamin D action extends far beyond bone health and calcium metabolism, showing broad effects on a variety of critical illnesses, including cancer, infections, cardiovascular and autoimmune diseases. Epidemiological studies indicated that low circulating vitamin D levels inversely correlate with cutaneous manifestations and bone abnormalities, clinical hallmarks of neurofibromatosis type 1 (NF1). NF1 is an autosomal dominant tumour predisposition syndrome causing significant pain and morbidity, for which limited treatment options are available. In this context, vitamin D or its analogues have been used to treat both skin and bone lesions in NF1 patients, alone or combined with other therapeutic agents. Here we provide an overview of vitamin D, its characteristic nutritional properties relevant for health benefits and its role in NF1 disorder. We focus on preclinical and clinical studies that demonstrated the clinical correlation between vitamin D status and NF1 disease, thus providing important insights into disease pathogenesis and new opportunities for targeted therapy.
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Affiliation(s)
- Claudia Riccardi
- Department of Chemical Sciences, University of Naples Federico II, via Cintia 21, I-80126 Naples, Italy;
- Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and InterUniversity Center for Research in Neurosciences, University of Campania Luigi Vanvitelli, via Sergio Pansini 5, I-80131 Naples, Italy; (L.P.); (F.N.); (S.S.)
| | - Lorena Perrone
- Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and InterUniversity Center for Research in Neurosciences, University of Campania Luigi Vanvitelli, via Sergio Pansini 5, I-80131 Naples, Italy; (L.P.); (F.N.); (S.S.)
| | - Filomena Napolitano
- Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and InterUniversity Center for Research in Neurosciences, University of Campania Luigi Vanvitelli, via Sergio Pansini 5, I-80131 Naples, Italy; (L.P.); (F.N.); (S.S.)
| | - Simone Sampaolo
- Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and InterUniversity Center for Research in Neurosciences, University of Campania Luigi Vanvitelli, via Sergio Pansini 5, I-80131 Naples, Italy; (L.P.); (F.N.); (S.S.)
| | - Mariarosa Anna Beatrice Melone
- Department of Advanced Medical and Surgical Sciences, 2nd Division of Neurology, Center for Rare Diseases and InterUniversity Center for Research in Neurosciences, University of Campania Luigi Vanvitelli, via Sergio Pansini 5, I-80131 Naples, Italy; (L.P.); (F.N.); (S.S.)
- Sbarro Institute for Cancer Research and Molecular Medicine, Department of Biology, Temple University, BioLife Building (015-00), 1900 North 12th Street, Philadelphia, PA 19122-6078, USA
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