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Teodori L, Omer M, Kjems J. RNA nanostructures for targeted drug delivery and imaging. RNA Biol 2024; 21:1-19. [PMID: 38555519 PMCID: PMC10984137 DOI: 10.1080/15476286.2024.2328440] [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: 03/04/2024] [Indexed: 04/02/2024] Open
Abstract
The RNA molecule plays a pivotal role in many biological processes by relaying genetic information, regulating gene expression, and serving as molecular machines and catalyzers. This inherent versatility of RNA has fueled significant advancements in the field of RNA nanotechnology, driving the engineering of complex nanoscale architectures toward biomedical applications, including targeted drug delivery and bioimaging. RNA polymers, serving as building blocks, offer programmability and predictability of Watson-Crick base pairing, as well as non-canonical base pairing, for the construction of nanostructures with high precision and stoichiometry. Leveraging the ease of chemical modifications to protect the RNA from degradation, researchers have developed highly functional and biocompatible RNA architectures and integrated them into preclinical studies for the delivery of payloads and imaging agents. This review offers an educational introduction to the use of RNA as a biopolymer in the design of multifunctional nanostructures applied to targeted delivery in vivo, summarizing physical and biological barriers along with strategies to overcome them. Furthermore, we highlight the most recent progress in the development of both small and larger RNA nanostructures, with a particular focus on imaging reagents and targeted cancer therapeutics in pre-clinical models and provide insights into the prospects of this rapidly evolving field.
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Affiliation(s)
- Laura Teodori
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus, Denmark
- Center for RNA Therapeutics towards Metabolic Diseases (RNA-META), Aarhus University, Aarhus, Denmark
| | - Marjan Omer
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus, Denmark
| | - Jørgen Kjems
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C, Denmark
- Center for Cellular Signal Patterns (CellPAT), Aarhus University, Aarhus, Denmark
- Center for RNA Therapeutics towards Metabolic Diseases (RNA-META), Aarhus University, Aarhus, Denmark
- Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
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2
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Anwar S, Mir F, Yokota T. Enhancing the Effectiveness of Oligonucleotide Therapeutics Using Cell-Penetrating Peptide Conjugation, Chemical Modification, and Carrier-Based Delivery Strategies. Pharmaceutics 2023; 15:pharmaceutics15041130. [PMID: 37111616 PMCID: PMC10140998 DOI: 10.3390/pharmaceutics15041130] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 03/28/2023] [Accepted: 03/28/2023] [Indexed: 04/29/2023] Open
Abstract
Oligonucleotide-based therapies are a promising approach for treating a wide range of hard-to-treat diseases, particularly genetic and rare diseases. These therapies involve the use of short synthetic sequences of DNA or RNA that can modulate gene expression or inhibit proteins through various mechanisms. Despite the potential of these therapies, a significant barrier to their widespread use is the difficulty in ensuring their uptake by target cells/tissues. Strategies to overcome this challenge include cell-penetrating peptide conjugation, chemical modification, nanoparticle formulation, and the use of endogenous vesicles, spherical nucleic acids, and smart material-based delivery vehicles. This article provides an overview of these strategies and their potential for the efficient delivery of oligonucleotide drugs, as well as the safety and toxicity considerations, regulatory requirements, and challenges in translating these therapies from the laboratory to the clinic.
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Affiliation(s)
- Saeed Anwar
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Farin Mir
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
| | - Toshifumi Yokota
- Department of Medical Genetics, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2H7, Canada
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3
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Ribeiro CMP, Higgs MG, Muhlebach MS, Wolfgang MC, Borgatti M, Lampronti I, Cabrini G. Revisiting Host-Pathogen Interactions in Cystic Fibrosis Lungs in the Era of CFTR Modulators. Int J Mol Sci 2023; 24:ijms24055010. [PMID: 36902441 PMCID: PMC10003689 DOI: 10.3390/ijms24055010] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 02/25/2023] [Accepted: 03/02/2023] [Indexed: 03/08/2023] Open
Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) modulators, a new series of therapeutics that correct and potentiate some classes of mutations of the CFTR, have provided a great therapeutic advantage to people with cystic fibrosis (pwCF). The main hindrances of the present CFTR modulators are related to their limitations in reducing chronic lung bacterial infection and inflammation, the main causes of pulmonary tissue damage and progressive respiratory insufficiency, particularly in adults with CF. Here, the most debated issues of the pulmonary bacterial infection and inflammatory processes in pwCF are revisited. Special attention is given to the mechanisms favoring the bacterial infection of pwCF, the progressive adaptation of Pseudomonas aeruginosa and its interplay with Staphylococcus aureus, the cross-talk among bacteria, the bronchial epithelial cells and the phagocytes of the host immune defenses. The most recent findings of the effect of CFTR modulators on bacterial infection and the inflammatory process are also presented to provide critical hints towards the identification of relevant therapeutic targets to overcome the respiratory pathology of pwCF.
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Affiliation(s)
- Carla M. P. Ribeiro
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Medicine, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Cell Biology and Physiology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Correspondence: (C.M.P.R.); (G.C.)
| | - Matthew G. Higgs
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Microbiology and Immunology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Marianne S. Muhlebach
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Pediatrics, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Matthew C. Wolfgang
- Marsico Lung Institute/Cystic Fibrosis Research Center, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
- Department of Microbiology and Immunology, The University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
| | - Monica Borgatti
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy
- Innthera4CF, Center on Innovative Therapies for Cystic Fibrosis, University of Ferrara, 44121 Ferrara, Italy
| | - Ilaria Lampronti
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy
- Innthera4CF, Center on Innovative Therapies for Cystic Fibrosis, University of Ferrara, 44121 Ferrara, Italy
| | - Giulio Cabrini
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy
- Innthera4CF, Center on Innovative Therapies for Cystic Fibrosis, University of Ferrara, 44121 Ferrara, Italy
- Correspondence: (C.M.P.R.); (G.C.)
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4
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Development of novel therapeutics for all individuals with CF (the future goes on). J Cyst Fibros 2023; 22 Suppl 1:S45-S49. [PMID: 36319570 DOI: 10.1016/j.jcf.2022.10.007] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 10/06/2022] [Accepted: 10/17/2022] [Indexed: 11/08/2022]
Abstract
Despite the major advances and successes in finding and establishing new treatments that tackle the basic defect in Cystic Fibrosis (CF), there is still an unmet need to bring these potentially curative therapies to all individuals with CF. Here, we review aspects of what is still missing to treat all individuals with CF by such approaches. On the one hand, we discuss novel holistic (high-throughput) approaches to elucidate mechanistic defects caused by distinct classes of mutations to identify novel drug targets. On the other hand, we examine therapeutic approaches to correct the gene in its own environment, i.e., in the genome.
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Oligonucleotide Enhancing Compound Increases Tricyclo-DNA Mediated Exon-Skipping Efficacy in the Mdx Mouse Model. Cells 2023; 12:cells12050702. [PMID: 36899837 PMCID: PMC10001065 DOI: 10.3390/cells12050702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/16/2023] [Accepted: 02/20/2023] [Indexed: 02/25/2023] Open
Abstract
Nucleic acid-based therapeutics hold great promise for the treatment of numerous diseases, including neuromuscular disorders, such as Duchenne muscular dystrophy (DMD). Some antisense oligonucleotide (ASO) drugs have already been approved by the US FDA for DMD, but the potential of this therapy is still limited by several challenges, including the poor distribution of ASOs to target tissues, but also the entrapment of ASO in the endosomal compartment. Endosomal escape is a well recognized limitation that prevents ASO from reaching their target pre-mRNA in the nucleus. Small molecules named oligonucleotide-enhancing compounds (OEC) have been shown to release ASO from endosomal entrapment, thus increasing ASO nuclear concentration and ultimately correcting more pre-mRNA targets. In this study, we evaluated the impact of a therapy combining ASO and OEC on dystrophin restoration in mdx mice. Analysis of exon-skipping levels at different time points after the co-treatment revealed improved efficacy, particularly at early time points, reaching up to 4.4-fold increase at 72 h post treatment in the heart compared to treatment with ASO alone. Significantly higher levels of dystrophin restoration were detected two weeks after the end of the combined therapy, reaching up to 2.7-fold increase in the heart compared to mice treated with ASO alone. Moreover, we demonstrated a normalization of cardiac function in mdx mice after a 12-week-long treatment with the combined ASO + OEC therapy. Altogether, these findings indicate that compounds facilitating endosomal escape can significantly improve the therapeutic potential of exon-skipping approaches offering promising perspectives for the treatment of DMD.
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Kim YJ, Krainer AR. Antisense Oligonucleotide Therapeutics for Cystic Fibrosis: Recent Developments and Perspectives. Mol Cells 2023; 46:10-20. [PMID: 36697233 PMCID: PMC9880599 DOI: 10.14348/molcells.2023.2172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 11/22/2022] [Accepted: 11/23/2022] [Indexed: 01/27/2023] Open
Abstract
Antisense oligonucleotide (ASO) technology has become an attractive therapeutic modality for various diseases, including Mendelian disorders. ASOs can modulate the expression of a target gene by promoting mRNA degradation or changing pre-mRNA splicing, nonsense-mediated mRNA decay, or translation. Advances in medicinal chemistry and a deeper understanding of post-transcriptional mechanisms have led to the approval of several ASO drugs for diseases that had long lacked therapeutic options. For instance, an ASO drug called nusinersen became the first approved drug for spinal muscular atrophy, improving survival and the overall disease course. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene cause cystic fibrosis (CF). Although Trikafta and other CFTR-modulation therapies benefit most CF patients, there is a significant unmet therapeutic need for a subset of CF patients. In this review, we introduce ASO therapies and their mechanisms of action, describe the opportunities and challenges for ASO therapeutics for CF, and discuss the current state and prospects of ASO therapies for CF.
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Affiliation(s)
- Young Jin Kim
- Department of Pediatrics, Mount Sinai Hospital, New York, NY 10029, USA
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7
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Dowdy SF, Setten RL, Cui XS, Jadhav SG. Delivery of RNA Therapeutics: The Great Endosomal Escape! Nucleic Acid Ther 2022; 32:361-368. [PMID: 35612432 PMCID: PMC9595607 DOI: 10.1089/nat.2022.0004] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 03/30/2022] [Indexed: 12/17/2022] Open
Abstract
RNA therapeutics, including siRNAs, antisense oligonucleotides, and other oligonucleotides, have great potential to selectively treat a multitude of human diseases, from cancer to COVID to Parkinson's disease. RNA therapeutic activity is mechanistically driven by Watson-Crick base pairing to the target gene RNA without the requirement of prior knowledge of the protein structure, function, or cellular location. However, before widespread use of RNA therapeutics becomes a reality, we must overcome a billion years of evolutionary defenses designed to keep invading RNAs from entering cells. Unlike small-molecule therapeutics that are designed to passively diffuse across the cell membrane, macromolecular RNA therapeutics are too large, too charged, and/or too hydrophilic to passively diffuse across the cellular membrane and are instead taken up into cells by endocytosis. However, similar to the cell membrane, endosomes comprise a lipid bilayer that entraps 99% or more of RNA therapeutics, even in semipermissive tissues such as the liver, central nervous system, and muscle. Consequently, before RNA therapeutics can achieve their ultimate clinical potential to treat widespread human disease, the rate-limiting delivery problem of endosomal escape must be solved in a clinically acceptable manner.
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Affiliation(s)
- Steven F. Dowdy
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA
| | - Ryan L. Setten
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA
| | - Xian-Shu Cui
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA
| | - Satish G. Jadhav
- Department of Cellular and Molecular Medicine, University of California San Diego, La Jolla, California, USA
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8
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Kreda SM. Oligonucleotide-based therapies for cystic fibrosis. Curr Opin Pharmacol 2022; 66:102271. [PMID: 35988291 DOI: 10.1016/j.coph.2022.102271] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Revised: 06/10/2022] [Accepted: 07/01/2022] [Indexed: 11/03/2022]
Abstract
In the clinically successful era of CFTR modulators and Theratyping, 10-20% of individuals with cystic fibrosis (CF) may develop disease due to CFTR mutations that remain undruggable. These individuals produce low levels of CFTR mRNA and/or not enough protein to be rescued with modulator drugs. Alternative therapeutic approaches to correct the CFTR defect at the mRNA level using nucleic acid technologies are currently feasible; e.g., oligonucleotides platforms, which are being rapidly developed to correct genetic disorders. Drug-like properties, great specificity, and predictable off-target effects by design make oligonucleotides a valuable approach with fewer clinical and ethical challenges than genomic editing strategies. Together with personalized and precision medicine approaches, oligonucleotides are ideal therapeutics to target CF-causing mutations that affect only a few individuals resilient to modulator therapies.
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Affiliation(s)
- Silvia M Kreda
- Marsico Lung Institute / Cystic Fibrosis Center, University of North Carolina at Chapel Hill, 6009 Thurston Bowles Bldg, Chapel Hill, NC, 27599-7248, USA; Department of Medicine, University of North Carolina at Chapel Hill, NC, 27599-7248, USA; Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, NC, 27599-7248, USA.
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9
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Harrison PT. CFTR RNA- and DNA-based therapies. Curr Opin Pharmacol 2022; 65:102247. [PMID: 35709547 DOI: 10.1016/j.coph.2022.102247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/20/2022] [Accepted: 05/01/2022] [Indexed: 11/29/2022]
Abstract
This review provides an update on recent developments of RNA- and DNA-based methodologies and their intracellular targets in the context of cystic fibrosis (CF) lung disease. Ultimately, clinical success will require a suitable delivery system, but since the cargo for all these strategies is nucleic acid, it should hopefully be possible to exploit delivery breakthroughs from one study and apply these innovations to other experiments in order to identify the best strategy for everyone with CF. Ultimately, it may be the same approach for everyone, or possibly a number of different strategies tailored to particular mutations or classes/groups of mutations. And whilst the current focus is on CF lung disease, in the longer term the goal is to treat all affected organs in people with CF such as the pancreas, gut, and liver.
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Affiliation(s)
- Patrick T Harrison
- Department of Physiology, BioSciences Institute, University College Cork, Ireland.
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10
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Cholon DM, Gentzsch M. Established and novel human translational models to advance cystic fibrosis research, drug discovery, and optimize CFTR-targeting therapeutics. Curr Opin Pharmacol 2022; 64:102210. [DOI: 10.1016/j.coph.2022.102210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/24/2022] [Accepted: 03/07/2022] [Indexed: 12/16/2022]
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11
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Michaels WE, Pena-Rasgado C, Kotaria R, Bridges RJ, Hastings ML. Open reading frame correction using splice-switching antisense oligonucleotides for the treatment of cystic fibrosis. Proc Natl Acad Sci U S A 2022; 119:e2114886119. [PMID: 35017302 PMCID: PMC8784102 DOI: 10.1073/pnas.2114886119] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 12/03/2021] [Indexed: 12/11/2022] Open
Abstract
CFTR gene mutations that result in the introduction of premature termination codons (PTCs) are common in cystic fibrosis (CF). This mutation type causes a severe form of the disease, likely because of low CFTR messenger RNA (mRNA) expression as a result of nonsense-mediated mRNA decay, as well as the production of a nonfunctional, truncated CFTR protein. Current therapeutics for CF, which target residual protein function, are less effective in patients with these types of mutations due in part to low CFTR protein levels. Splice-switching antisense oligonucleotides (ASOs), designed to induce skipping of exons in order to restore the mRNA open reading frame, have shown therapeutic promise preclinically and clinically for a number of diseases. We hypothesized that ASO-mediated skipping of CFTR exon 23 would recover CFTR activity associated with terminating mutations in the exon, including CFTR p.W1282X, the fifth most common mutation in CF. Here, we show that CFTR lacking the amino acids encoding exon 23 is partially functional and responsive to corrector and modulator drugs currently in clinical use. ASO-induced exon 23 skipping rescued CFTR expression and chloride current in primary human bronchial epithelial cells isolated from a homozygote CFTR-W1282X patient. These results support the use of ASOs in treating CF patients with CFTR class I mutations in exon 23 that result in unstable CFTR mRNA and truncations of the CFTR protein.
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Affiliation(s)
- Wren E Michaels
- Center for Genetic Diseases, Chicago Medical School, Rosalind Franklin University of Science and Medicine, North Chicago, IL 60064
- School of Graduate and Postdoctoral Studies, Rosalind Franklin University of Science and Medicine, North Chicago, IL 60064
| | - Cecilia Pena-Rasgado
- Center for Genetic Diseases, Chicago Medical School, Rosalind Franklin University of Science and Medicine, North Chicago, IL 60064
| | - Rusudan Kotaria
- Center for Genetic Diseases, Chicago Medical School, Rosalind Franklin University of Science and Medicine, North Chicago, IL 60064
| | - Robert J Bridges
- Center for Genetic Diseases, Chicago Medical School, Rosalind Franklin University of Science and Medicine, North Chicago, IL 60064;
| | - Michelle L Hastings
- Center for Genetic Diseases, Chicago Medical School, Rosalind Franklin University of Science and Medicine, North Chicago, IL 60064;
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12
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Liczner C, Hanna CC, Payne RJ, Wilds CJ. Generation of oligonucleotide conjugates via one-pot diselenide-selenoester ligation-deselenization/alkylation. Chem Sci 2022; 13:410-420. [PMID: 35126973 PMCID: PMC8729807 DOI: 10.1039/d1sc04937b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 11/17/2021] [Indexed: 12/23/2022] Open
Abstract
A breadth of strategies are needed to efficiently modify oligonucleotides with peptides or lipids to capitalize on their therapeutic and diagnostic potential, including the modulation of in vivo chemical stability and for applications in cell-targeting and cell-permeability. The chemical linkages typically used in peptide oligonucleotide conjugates (POCs) have limitations in terms of stability and/or ease of synthesis. Herein, we report an efficient method for POC synthesis using a diselenide-selenoester ligation (DSL)-deselenization strategy that rapidly generates a stable amide linkage between the two biomolecules. This conjugation strategy is underpinned by a novel selenide phosphoramidite building block that can be incorporated into an oligonucleotide by solid-phase synthesis to generate diselenide dimer molecules. These can be rapidly ligated with peptide selenoesters and, following in situ deselenization, lead to the efficient generation of POCs. The diselenide within the oligonucleotide also serves as a flexible functionalisation handle that can be leveraged for fluorescent labelling, as well as for alkylation to generate micelles.
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Affiliation(s)
- Christopher Liczner
- Department of Chemistry and Biochemistry, Concordia University 7141 Rue Sherbrooke Ouest Montréal Québec H4B 1R6 Canada
| | - Cameron C Hanna
- School of Chemistry, The University of Sydney Sydney NSW 2006 Australia.,Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney Sydney NSW 2006 Australia
| | - Richard J Payne
- School of Chemistry, The University of Sydney Sydney NSW 2006 Australia.,Australian Research Council Centre of Excellence for Innovations in Peptide and Protein Science, The University of Sydney Sydney NSW 2006 Australia
| | - Christopher J Wilds
- Department of Chemistry and Biochemistry, Concordia University 7141 Rue Sherbrooke Ouest Montréal Québec H4B 1R6 Canada
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