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Cell Metabolism Apr 2018RNA-targeted therapies represent a platform for drug discovery involving chemically modified oligonucleotides, a wide range of cellular RNAs, and a novel target-binding... (Review)
Review
RNA-targeted therapies represent a platform for drug discovery involving chemically modified oligonucleotides, a wide range of cellular RNAs, and a novel target-binding motif, Watson-Crick base pairing. Numerous hurdles considered by many to be impassable have been overcome. Today, four RNA-targeted therapies are approved for commercial use for indications as diverse as Spinal Muscular Atrophy (SMA) and reduction of low-density lipoprotein cholesterol (LDL-C) and by routes of administration including subcutaneous, intravitreal, and intrathecal delivery. The technology is efficient and supports approaching "undruggable" targets. Three additional agents are progressing through registration, and more are in clinical development, representing several chemical and structural classes. Moreover, progress in understanding the molecular mechanisms by which these drugs work has led to steadily better clinical performance and a wide range of mechanisms that may be exploited for therapeutic purposes. Here we summarize the progress, future challenges, and opportunities for this drug discovery platform.
Topics: Animals; Drug Discovery; Genetic Therapy; Humans; Molecular Targeted Therapy; Muscular Atrophy, Spinal; Oligoribonucleotides, Antisense; RNA, Small Interfering
PubMed: 29617640
DOI: 10.1016/j.cmet.2018.03.004 -
Pharmacological Reviews Oct 2020RNA-based therapies, including RNA molecules as drugs and RNA-targeted small molecules, offer unique opportunities to expand the range of therapeutic targets. Various...
RNA-based therapies, including RNA molecules as drugs and RNA-targeted small molecules, offer unique opportunities to expand the range of therapeutic targets. Various forms of RNAs may be used to selectively act on proteins, transcripts, and genes that cannot be targeted by conventional small molecules or proteins. Although development of RNA drugs faces unparalleled challenges, many strategies have been developed to improve RNA metabolic stability and intracellular delivery. A number of RNA drugs have been approved for medical use, including aptamers (e.g., pegaptanib) that mechanistically act on protein target and small interfering RNAs (e.g., patisiran and givosiran) and antisense oligonucleotides (e.g., inotersen and golodirsen) that directly interfere with RNA targets. Furthermore, guide RNAs are essential components of novel gene editing modalities, and mRNA therapeutics are under development for protein replacement therapy or vaccination, including those against unprecedented severe acute respiratory syndrome coronavirus pandemic. Moreover, functional RNAs or RNA motifs are highly structured to form binding pockets or clefts that are accessible by small molecules. Many natural, semisynthetic, or synthetic antibiotics (e.g., aminoglycosides, tetracyclines, macrolides, oxazolidinones, and phenicols) can directly bind to ribosomal RNAs to achieve the inhibition of bacterial infections. Therefore, there is growing interest in developing RNA-targeted small-molecule drugs amenable to oral administration, and some (e.g., risdiplam and branaplam) have entered clinical trials. Here, we review the pharmacology of novel RNA drugs and RNA-targeted small-molecule medications, with a focus on recent progresses and strategies. Challenges in the development of novel druggable RNA entities and identification of viable RNA targets and selective small-molecule binders are discussed. SIGNIFICANCE STATEMENT: With the understanding of RNA functions and critical roles in diseases, as well as the development of RNA-related technologies, there is growing interest in developing novel RNA-based therapeutics. This comprehensive review presents pharmacology of both RNA drugs and RNA-targeted small-molecule medications, focusing on novel mechanisms of action, the most recent progress, and existing challenges.
Topics: Aptamers, Nucleotide; Betacoronavirus; COVID-19; Chemistry Techniques, Analytical; Clustered Regularly Interspaced Short Palindromic Repeats; Coronavirus Infections; Drug Delivery Systems; Drug Development; Drug Discovery; Humans; MicroRNAs; Oligonucleotides, Antisense; Pandemics; Pneumonia, Viral; RNA; RNA, Antisense; RNA, Messenger; RNA, Ribosomal; RNA, Small Interfering; RNA, Viral; Ribonucleases; Riboswitch; SARS-CoV-2
PubMed: 32929000
DOI: 10.1124/pr.120.019554 -
European Heart Journal May 2023Epicardium and epicardium-derived cells are critical players in myocardial fibrosis. Mesenchymal stem cell-derived extracellular vesicles (EVs) have been studied for...
AIMS
Epicardium and epicardium-derived cells are critical players in myocardial fibrosis. Mesenchymal stem cell-derived extracellular vesicles (EVs) have been studied for cardiac repair to improve cardiac remodelling, but the actual mechanisms remain elusive. The aim of this study is to investigate the mechanisms of EV therapy for improving cardiac remodelling and develop a promising treatment addressing myocardial fibrosis.
METHODS AND RESULTS
Extracellular vesicles were intrapericardially injected for mice myocardial infarction treatment. RNA-seq, in vitro gain- and loss-of-function experiments, and in vivo studies were performed to identify targets that can be used for myocardial fibrosis treatment. Afterward, a lipid nanoparticle-based long non-coding RNA (lncRNA) therapy was prepared for mouse and porcine models of myocardial infarction treatment. Intrapericardial injection of EVs improved adverse myocardial remodelling in mouse models of myocardial infarction. Mechanistically, Tcf21 was identified as a potential target to improve cardiac remodelling. Loss of Tcf21 function in epicardium-derived cells caused increased myofibroblast differentiation, whereas forced Tcf21 overexpression suppressed transforming growth factor-β signalling and myofibroblast differentiation. LncRNA-Tcf21 antisense RNA inducing demethylation (TARID) that enriched in EVs was identified to up-regulate Tcf21 expression. Formulated lncRNA-TARID-laden lipid nanoparticles up-regulated Tcf21 expression in epicardium-derived cells and improved cardiac function and histology in mouse and porcine models of myocardial infarction.
CONCLUSION
This study identified Tcf21 as a critical target for improving cardiac fibrosis. Up-regulating Tcf21 by using lncRNA-TARID-laden lipid nanoparticles could be a promising way to treat myocardial fibrosis. This study established novel mechanisms underlying EV therapy for improving adverse remodelling and proposed a lncRNA therapy for cardiac fibrosis.
Topics: Mice; Animals; Swine; RNA, Long Noncoding; RNA, Antisense; Ventricular Remodeling; Myocardial Infarction; Fibrosis; Demethylation
PubMed: 36916305
DOI: 10.1093/eurheartj/ehad114 -
RNA (New York, N.Y.) Mar 2020The use of synthetic RNA for therapeutics requires that the in vitro synthesis process be robust and efficient. The technology used for the synthesis of these in...
The use of synthetic RNA for therapeutics requires that the in vitro synthesis process be robust and efficient. The technology used for the synthesis of these in vitrotranscribed RNAs, predominantly using phage RNA polymerases (RNAPs), is well established. However, transcripts synthesized with RNAPs are known to display an immune-stimulatory activity in vivo that is often undesirable. Previous studies have identified double-stranded RNA (dsRNA), a major by-product of the in vitro transcription (IVT) process, as a trigger of cellular immune responses. Here we describe the characterization of a high-temperature IVT process using thermostable T7 RNAPs to synthesize functional mRNAs that demonstrate reduced immunogenicity without the need for a post-synthesis purification step. We identify features that drive the production of two kinds of dsRNA by-products-one arising from 3' extension of the run-off product and one formed by the production of antisense RNAs-and demonstrate that at a high temperature, T7 RNAP has reduced 3'-extension of the run-off product. We show that template-encoded poly(A) tailing does not affect 3'-extension but reduces the formation of the antisense RNA by-products. Combining high-temperature IVT with template-encoded poly(A) tailing prevents the formation of both kinds of dsRNA by-products generating functional mRNAs with reduced immunogenicity.
Topics: Bacteriophage T7; DNA-Directed RNA Polymerases; Immunity, Cellular; RNA; RNA, Antisense; RNA, Double-Stranded; RNA, Messenger; Transcription, Genetic
PubMed: 31900329
DOI: 10.1261/rna.073858.119 -
Methods in Molecular Biology (Clifton,... 2018RNA molecules interact with proteins to perform a variety of functions in living cells. The binding partners of many RNAs, in particular the newly discovered class of...
RNA molecules interact with proteins to perform a variety of functions in living cells. The binding partners of many RNAs, in particular the newly discovered class of long noncoding RNAs (lncRNAs), remain largely unknown. RNA antisense purification coupled with mass spectrometry (RAP-MS) is a method that enables the identification of direct and specific protein interaction partners of a specific RNA molecule. Because RAP-MS uses direct RNA-protein cross-linking methods coupled along with highly denaturing purification conditions, RAP-MS provides a short list of high confidence protein interactors.
Topics: Animals; Cell Fractionation; Detergents; Isotope Labeling; Mass Spectrometry; Mice; Mouse Embryonic Stem Cells; Peptides; Protein Binding; RNA, Antisense; RNA-Binding Proteins
PubMed: 29130217
DOI: 10.1007/978-1-4939-7213-5_31 -
Translational Research : the Journal of... Sep 2020Extensive antibiotic use combined with poor historical drug stewardship practices have created a medical crisis in which once treatable bacterial infections are now... (Review)
Review
Extensive antibiotic use combined with poor historical drug stewardship practices have created a medical crisis in which once treatable bacterial infections are now increasingly unmanageable. To combat this, new antibiotics will need to be developed and safeguarded. An emerging class of antibiotics based upon nuclease-stable antisense technologies has proven valuable in preclinical testing against a variety of bacterial pathogens. This review describes the current state of development of antisense-based antibiotics, the mechanisms thus far employed by these compounds, and possible future avenues of research.
Topics: Animals; Anti-Bacterial Agents; Bacteria; Drug Resistance, Microbial; Gene Transfer Techniques; Humans; RNA, Antisense
PubMed: 32522669
DOI: 10.1016/j.trsl.2020.06.001 -
Nucleic Acid Therapeutics Jun 2021The number of novel potential RNA-based antisense therapeutics is rapidly increasing. However, efficient delivery to target tissues is still the main factor that limits...
The number of novel potential RNA-based antisense therapeutics is rapidly increasing. However, efficient delivery to target tissues is still the main factor that limits their translation into the clinic. Although many groups in academia and industry are working toward the development of methods to improve antisense delivery to overcome this limitation, there are very few coordinated efforts to learn from the experience of other investigators by sharing "negative" results. In the field of nucleic acid therapeutics, or any other type of therapeutics, the ultimate aim of most research projects is to develop novel or improved therapeutic strategies. It seems only logical that experiments are thought to yield a "negative result" if there is an absence of an improvement in some parameter related to potential therapeutic efficacy. These data often do not get published in scientific journals or presented at scientific meetings. However, positive and negative results obtained from scientifically sound experiments are equally valuable in facilitating progress in the field. They avoid unnecessary duplication of experiments and allow researchers to take approaches that did not yield the predicted result into account when designing new experiments.
Topics: Negative Results; Nucleic Acids; Oligonucleotides, Antisense; RNA, Antisense
PubMed: 34097476
DOI: 10.1089/nat.2021.0028 -
Journal of Molecular Neuroscience : MN Jan 2016The transcriptome of a cell is made up of a varied array of RNA species, including protein-coding RNAs, long non-coding RNAs, short non-coding RNAs, and circular RNAs.... (Review)
Review
The transcriptome of a cell is made up of a varied array of RNA species, including protein-coding RNAs, long non-coding RNAs, short non-coding RNAs, and circular RNAs. The cellular transcriptome is dynamic and can change depending on environmental factors, disease state and cellular context. The human brain has perhaps the most diverse transcriptome profile that is enriched for many species of RNA, including antisense transcripts. Antisense transcripts are produced when both the plus and minus strand of the DNA helix are transcribed at a particular locus. This results in an RNA transcript that has a partial or complete overlap with an intronic or exonic region of the sense transcript. While antisense transcription is known to occur at some level in most organisms, this review focuses specifically on antisense transcription in the brain and how regulation of genes by antisense transcripts can contribute to functional aspects of the healthy and diseased brain. First, we discuss different techniques that can be used in the identification and quantification of antisense transcripts. This is followed by examples of antisense transcription and modes of regulatory function that have been identified in the brain.
Topics: Brain; DNA, Antisense; Humans; RNA, Antisense; Transcriptome
PubMed: 26697858
DOI: 10.1007/s12031-015-0694-3 -
Microbiology Spectrum Jul 2018Although bacterial genomes are usually densely protein-coding, genome-wide mapping approaches of transcriptional start sites revealed that a significant fraction of the... (Review)
Review
Although bacterial genomes are usually densely protein-coding, genome-wide mapping approaches of transcriptional start sites revealed that a significant fraction of the identified promoters drive the transcription of noncoding RNAs. These can be -acting RNAs, mainly originating from intergenic regions and, in many studied examples, possessing regulatory functions. However, a significant fraction of these noncoding RNAs consist of natural antisense transcripts (asRNAs), which overlap other transcriptional units. Naturally occurring asRNAs were first observed to play a role in bacterial plasmid replication and in bacteriophage λ more than 30 years ago. Today's view is that asRNAs abound in all three domains of life. There are several examples of asRNAs in bacteria with clearly defined functions. Nevertheless, many asRNAs appear to result from pervasive initiation of transcription, and some data point toward global functions of such widespread transcriptional activity, explaining why the search for a specific regulatory role is sometimes futile. In this review, we give an overview about the occurrence of antisense transcription in bacteria, highlight particular examples of functionally characterized asRNAs, and discuss recent evidence pointing at global relevance in RNA processing and transcription-coupled DNA repair.
Topics: Bacteria; Bacterial Proteins; DNA Repair; Evolution, Molecular; Gene Expression Regulation, Bacterial; Genome, Bacterial; Plasmids; RNA, Antisense; RNA, Bacterial; RNA, Untranslated; Transcription, Genetic
PubMed: 30003872
DOI: 10.1128/microbiolspec.RWR-0029-2018 -
Human Molecular Genetics Sep 2014Recent years have seen the increasing understanding of the crucial role of RNA in the functioning of the eukaryotic genome. These discoveries, fueled by the achievements... (Review)
Review
Recent years have seen the increasing understanding of the crucial role of RNA in the functioning of the eukaryotic genome. These discoveries, fueled by the achievements of the FANTOM, and later GENCODE and ENCODE consortia, led to the recognition of the important regulatory roles of natural antisense transcripts (NATs) arising from what was previously thought to be 'junk DNA'. Roughly defined as non-coding regulatory RNA transcribed from the opposite strand of a coding gene locus, NATs are proving to be a heterogeneous group with high potential for therapeutic application. Here, we attempt to summarize the rapidly growing knowledge about this important non-coding RNA subclass.
Topics: Gene Expression; Gene Targeting; Genome; Humans; RNA, Antisense; RNA, Untranslated; Transcription, Genetic
PubMed: 24838284
DOI: 10.1093/hmg/ddu207