51
|
Abstract
IMPORTANCE OF THE FIELD Despite numerous advances made during the last decade in brain tumor therapy, the prognosis of glioblastoma has not improved and these tumors inevitably recur with no effective treatment. Thus, any new therapeutic strategy to target this most malignant tumor will be of significant benefit. RNAi is a powerful gene silencing method that might be used in combination with other agents to improve the efficacy of glioblastoma treatment. AREAS COVERED IN THIS REVIEW Recent progress and challenges of pre-clinical and clinical research of RNAi therapy for glioblastoma. The review covers literature from 2003 to 2009. WHAT THE READER WILL GAIN The principle of RNA interference therapy, three categories of RNAi triggers, different RNAi delivery system and pre-clinical and clinical studies that are currently underway to evaluate the validity of RNAi as a potential therapeutic strategy against glioblastoma are discussed. TAKE HOME MESSAGE RNA inference therapy combined with other therapeutics may offer therapeutic potential for glioblastoma multiforme. Further studies are required to develop more efficient and specific delivery systems, select suitable gene targets, optimize treatment dose and administration schedule, evaluate the efficacy of combination treatment strategies, establish a validated clinical response measure system etc.
Collapse
Affiliation(s)
- Dongsheng Guo
- Department of Neurosurgery, Huazhong University of Sciences and Technology, Tongji Medical College, Tongji Hospital, Wuhan, China.
| | | | | | | |
Collapse
|
52
|
Anesti AM, Coffin RS. Delivery of RNA interference triggers to sensory neurons in vivo using herpes simplex virus. Expert Opin Biol Ther 2010; 10:89-103. [PMID: 20420517 DOI: 10.1517/14712590903379486] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
IMPORTANCE OF THE FIELD Pain is a hugely important area of research attracting considerable academic and commercial interest. However, the application of RNA interference (RNAi) to the study of nociceptive processes and the development of new analgesics has been limited by the specific challenges associated with the delivery of RNAi triggers to the cell bodies of sensory neurons in the dorsal root ganglia (DRG). AREAS COVERED IN THIS REVIEW In the past five years, delivery of small-interfering RNA (siRNA) to the DRG and spinal cord has achieved effective and specific silencing of targeted genes in various animal models of pain. However, delivery of short-hairpin RNA (shRNA) or artificial microRNA (miRNA) to sensory neurons in vivo has not been feasible using most delivery systems currently available. WHAT THE READER WILL GAIN Replication-defective vectors based on herpes simplex virus (HSV), which are particularly efficient at targeting DRG neurons, have been recently engineered to express shRNA and artificial miRNA. Whilst silencing induced by siRNA is transient and requires relatively high doses of silencing triggers, HSV-mediated expression of shRNA/miRNA in sensory neurons allows silencing of targeted genes for at least one week following a single injection. TAKE HOME MESSAGE The potential to use inducible or tissue-specific promoters and to simultaneously silence multiple gene targets, in addition to recent studies suggesting that artificial miRNAs may have improved safety profiles, hold clear advantages for the use of miRNA-based vectors for gene silencing in sensory neurons.
Collapse
|
53
|
Hammond NB, Tolbert BS, Kierzek R, Turner DH, Kennedy SD. RNA internal loops with tandem AG pairs: the structure of the 5'GAGU/3'UGAG loop can be dramatically different from others, including 5'AAGU/3'UGAA. Biochemistry 2010; 49:5817-27. [PMID: 20481618 PMCID: PMC2900907 DOI: 10.1021/bi100332r] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
![]()
Thermodynamic stabilities of 2 × 2 nucleotide tandem AG internal loops in RNA range from −1.3 to +3.4 kcal/mol at 37 °C and are not predicted well with a hydrogen-bonding model. To provide structural information to facilitate development of more sophisticated models for the sequence dependence of stability, we report the NMR solution structures of five RNA duplexes: (rGACGAGCGUCA)2, (rGACUAGAGUCA)2, (rGACAAGUGUCA)2, (rGGUAGGCCA)2, and (rGACGAGUGUCA)2. The structures of these duplexes are compared to that of the previously solved (rGGCAGGCC)2 (Wu, M., SantaLucia, J., Jr., and Turner, D. H. (1997) Biochemistry 36, 4449−4460). For loops bounded by Watson−Crick pairs, the AG and Watson−Crick pairs are all head-to-head imino-paired (cis Watson−Crick/Watson−Crick). The structures suggest that the sequence-dependent stability may reflect non-hydrogen-bonding interactions. Of the two loops bounded by G-U pairs, only the 5′UAGG/3′GGAU loop adopts canonical UG wobble pairing (cis Watson−Crick/Watson−Crick), with AG pairs that are only weakly imino-paired. Strikingly, the 5′GAGU/3′UGAG loop has two distinct duplex conformations, the major of which has both guanosine residues (G4 and G6 in (rGACGAGUGUCA)2) in a syn glycosidic bond conformation and forming a sheared GG pair (G4-G6*, GG trans Watson−Crick/Hoogsteen), both uracils (U7 and U7*) flipped out of the helix, and an AA pair (A5-A5*) in a dynamic or stacked conformation. These structures provide benchmarks for computational investigations into interactions responsible for the unexpected differences in loop free energies and structure.
Collapse
Affiliation(s)
- Nicholas B Hammond
- Department of Chemistry, University of Rochester, Rochester, New York 14627-0216, USA
| | | | | | | | | |
Collapse
|
54
|
Snead NM, Rossi JJ. Biogenesis and function of endogenous and exogenous siRNAs. WILEY INTERDISCIPLINARY REVIEWS-RNA 2010; 1:117-31. [PMID: 21956909 DOI: 10.1002/wrna.14] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
RNA interference (RNAi) is a sequence-specific gene silencing, or 'knockdown', mechanism facilitated by short duplex strands of RNA with sequence complementarity to target mRNAs. RNAi has many different forms, including posttranscriptional gene silencing (PTGS), and transcriptional gene silencing (TGS). Here, we review the biogenesis and function of an endogenous set of small RNA gene regulators, called microRNAs, as well as the mechanism of exogenously delivered small interfering RNAs. The potential applications of RNAi-based therapeutics are also highlighted.
Collapse
Affiliation(s)
- Nicholas M Snead
- Department of Molecular and Cellular Biology, Beckman Research Institute of the City of Hope, Duarte, CA 91010, USA
| | | |
Collapse
|
55
|
Katakowski JA, Palliser D. siRNA-based topical microbicides targeting sexually transmitted infections. CURRENT OPINION IN MOLECULAR THERAPEUTICS 2010; 12:192-202. [PMID: 20373263 PMCID: PMC3282625] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Sexually transmitted infections (STIs) are a major cause of morbidity and mortality worldwide. Although a vaccine is available for HPV, no effective vaccines exist for the HIV-1 and HSV-2 viral pathogens, and there are no cures for these infections. Furthermore, recent setbacks in clinical trials, such as the failure of the STEP trial to prevent HIV-1 infection, have emphasized the need to develop alternative approaches to interrupt the transmission of these pathogens. One alternative strategy is represented by the use of topically applied microbicides, and such agents are being developed against various viruses. RNAi-based microbicides have recently been demonstrated to prevent HSV-2 transmission, and may be useful for targeting multiple STIs. In this review, microbicides that are under development for the prevention of STIs are described, with a focus on topically applied microbicidal siRNAs.
Collapse
|
56
|
Bennett CF, Swayze EE. RNA targeting therapeutics: molecular mechanisms of antisense oligonucleotides as a therapeutic platform. Annu Rev Pharmacol Toxicol 2010; 50:259-93. [PMID: 20055705 DOI: 10.1146/annurev.pharmtox.010909.105654] [Citation(s) in RCA: 990] [Impact Index Per Article: 70.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Dramatic advances in understanding of the roles RNA plays in normal health and disease have greatly expanded over the past 10 years and have made it clear that scientists are only beginning to comprehend the biology of RNAs. It is likely that RNA will become an increasingly important target for therapeutic intervention; therefore, it is important to develop strategies for therapeutically modulating RNA function. Antisense oligonucleotides are perhaps the most direct therapeutic strategy to approach RNA. Antisense oligonucleotides are designed to bind to the target RNA by well-characterized Watson-Crick base pairing, and once bound to the target RNA, modulate its function through a variety of postbinding events. This review focuses on the molecular mechanisms by which antisense oligonucleotides can be designed to modulate RNA function in mammalian cells and how synthetic oligonucleotides behave in the body.
Collapse
Affiliation(s)
- C Frank Bennett
- Isis Pharmaceuticals, Inc., Carlsbad, California 92008, USA.
| | | |
Collapse
|
57
|
Abstract
Posttranscriptional regulation of gene expression is increasingly recognized as a model for inherited and acquired disease. Recent work has expanded understanding of the range of mechanisms that regulate several of these distinct steps, including messenger RNA (mRNA) splicing, trafficking, and/or stability. Each of these pathways is implicated in disease pathogenesis, and each represents important avenues for therapeutic intervention. This review summarizes important mechanisms controlling mRNA processing and the regulation of mRNA degradation, including the role of microRNAs and RNA binding proteins. These pathways provide important opportunities for therapeutic targeting directed at splicing and degradation in order to attenuate genetic defects in RNA metabolism. We will highlight developments in vector development and validation for therapeutic manipulation of mRNA expression with a focus on potential applications in metabolic and immunomediated liver disease.
Collapse
Affiliation(s)
| | - Nicholas O. Davidson
- Contact information: Nicholas O. Davidson, MD, Division of Gastroenterology, Box 8124, Washington University School of Medicine, 660. Euclid Avenue, St. Louis, MO 63110, Phone: (314)-362-2027,
| |
Collapse
|
58
|
Iliopoulos D, Drosatos K, Hiyama Y, Goldberg IJ, Zannis VI. MicroRNA-370 controls the expression of microRNA-122 and Cpt1alpha and affects lipid metabolism. J Lipid Res 2010; 51:1513-23. [PMID: 20124555 DOI: 10.1194/jlr.m004812] [Citation(s) in RCA: 242] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
We previously observed that treatment of mice with a dominant negative form of cJun (dn-cJun) increased the expression of genes involved in lipid metabolism and modulated the expression of nine microRNAs (miR). To investigate the potential effect of these miRs on the expression of the genes of lipid metabolism, we performed studies in cultured HepG2 cells. Transfection of HepG2 cells with sense or antisense miR-370 or miR-122 upregulated and downregulated, respectively, the transcription factor sterol-regulatory element binding protein 1c (SREBP-1c) and the enzymes diacylglycerol acyltransferase-2 (DGAT2), fatty acid synthase (FAS), and acyl-CoA carboxylase 1 (ACC1) that regulate fatty acid and triglyceride biosynthesis. The other seven miRs identified by the miR array screening did not affect the expression of lipogenic genes. miR-370 upregulated the expression of miR-122. Furthermore, the effect of miR-370 on the expression of the lipogenic genes was abolished by antisense miR-122. miR-370 targets the 3' untranslated region (UTR) of Cpt1alpha, and it downregulated the expression of the carnitine palmitoyl transferase 1alpha (Cpt1alpha) gene as well as the rate of beta oxidation. Our data suggest that miR-370 acting via miR-122 may have a causative role in the accumulation of hepatic triglycerides by modulating initially the expression of SREBP-1c, DGAT2, and Cpt1alpha and, subsequently, the expression of other genes that affect lipid metabolism.
Collapse
Affiliation(s)
- Dimitrios Iliopoulos
- Department of Biological Chemistry and Molecular Pharmacology, School of Medicine, Harvard University, Boston, MA, USA
| | | | | | | | | |
Collapse
|
59
|
Jackson AL, Linsley PS. Recognizing and avoiding siRNA off-target effects for target identification and therapeutic application. Nat Rev Drug Discov 2010; 9:57-67. [PMID: 20043028 DOI: 10.1038/nrd3010] [Citation(s) in RCA: 728] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Small interfering RNAs (siRNAs) are widely used to study gene function owing to the ease with which they silence target genes, and there is considerable interest in their potential for therapeutic applications. In a remarkably short time since their discovery, siRNAs have entered human clinical trials in various disease areas. However, rapid acceptance of the use of siRNAs has been accompanied by recognition of several hurdles for the technology, including a lack of specificity. Off-target activity can complicate the interpretation of phenotypic effects in gene-silencing experiments and can potentially lead to unwanted toxicities. Here, we describe the types of off-target effects of siRNAs and methods to mitigate them, to help enable effective application of this exciting technology.
Collapse
Affiliation(s)
- Aimee L Jackson
- Regulus Therapeutics, Inc., 1896 Rutherford Road, Carlsbad, CA 92008, USA.
| | | |
Collapse
|
60
|
Abstract
In this issue, Kamisuki and colleagues characterize fatostatin. This compound inhibits the activity of SREBPs, the master transcription factors of lipid homeostasis. This useful laboratory tool also improved the lipid profile of obese mice; does this have clinical implications?
Collapse
|
61
|
The therapeutic potential of microRNAs in nervous system damage, degeneration, and repair. Neuromolecular Med 2009; 11:153-61. [PMID: 19763905 DOI: 10.1007/s12017-009-8086-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2009] [Accepted: 08/25/2009] [Indexed: 02/07/2023]
Abstract
MicroRNAS (miRNAs) have been suggested to play important roles in the central nervous system during development as well as disease. miRNAs appear to be dysregulated in a number of neurodegenerative diseases, developmental disorders, and as a result of stroke. Each miRNA has the ability to regulate hundreds of messenger RNA transcripts, both by causing degradation of the mRNA and by inhibition of protein translation. Recent findings suggest that it may eventually be possible to treat some neurological disorders by restoring or inhibiting miRNAs altered by disease pathology. Both viral delivery and administration of modified oligonucleotides mimicking or inhibiting specific miRNAs have been effective in model systems. Artificial miRNAs have also been generated for the repression of specific transcripts. Alteration of miRNA expression by disease and insult also holds the potential for improved diagnostic tools. Finally, miRNAs have been shown to control cellular proliferation and specification, suggesting that manipulation of miRNAs in cultured cells could result in more convenient generation of pure cell populations for transplantation.
Collapse
|
62
|
microRNA: emerging therapeutic targets in acute ischemic diseases. Pharmacol Ther 2009; 125:92-104. [PMID: 19896977 DOI: 10.1016/j.pharmthera.2009.10.003] [Citation(s) in RCA: 144] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2009] [Accepted: 10/05/2009] [Indexed: 02/08/2023]
Abstract
microRNAs (miRNAs) are 21-23-nucleotide non-protein-coding RNA molecules that act as negative regulators of gene expression, modulating the stability and/or the translational efficiency of target messenger RNAs. This review describes miRNA regulation and function in tissue response to acute ischemia. We focused our attention on a subset of miRNAs that have been found de-regulated in different studies, suggesting that they may represent "master ischemic" miRNAs, playing a pathogenetic role in different components of tissue response to ischemia. First, we analyzed the role of miRNAs in cell response to hypoxia, a crucial component of ischemia, and in angiogenesis. Then, we describe miRNAs role in acute myocardial infarction as much as in hindlimb, cerebral, hepatic and retinal ischemia. The role played by specific miRNAs in the regulation of apoptosis, fibrosis, regeneration and myocardial arrhythmias is illustrated. The identification of specific miRNAs as key regulators of the response to ischemia has opened new clinical avenues. miRNAs may constitute excellent non-invasive disease biomarkers. Furthermore, innovative strategies targeting miRNAs, aimed to reduce the levels of pathogenic or aberrantly expressed miRNAs or to elevate the levels of miRNAs with beneficial functions, have been developed and could be applied in the treatment of ischemic diseases.
Collapse
|
63
|
Transfection of small RNAs globally perturbs gene regulation by endogenous microRNAs. Nat Biotechnol 2009; 27:549-55. [PMID: 19465925 DOI: 10.1038/nbt.1543] [Citation(s) in RCA: 362] [Impact Index Per Article: 24.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Transfection of small RNAs (such as small interfering RNAs (siRNAs) and microRNAs (miRNAs)) into cells typically lowers expression of many genes. Unexpectedly, increased expression of genes also occurs. We investigated whether this upregulation results from a saturation effect--that is, competition among the transfected small RNAs and the endogenous pool of miRNAs for the intracellular machinery that processes small RNAs. To test this hypothesis, we analyzed genome-wide transcript responses from 151 published transfection experiments in seven different human cell types. We show that targets of endogenous miRNAs are expressed at significantly higher levels after transfection, consistent with impaired effectiveness of endogenous miRNA repression. This effect exhibited concentration and temporal dependence. Notably, the profile of endogenous miRNAs can be largely inferred by correlating miRNA sites with gene expression changes after transfections. The competition and saturation effects have practical implications for miRNA target prediction, the design of siRNA and short hairpin RNA (shRNA) genomic screens and siRNA therapeutics.
Collapse
|
64
|
Khan AA, Betel D, Miller ML, Sander C, Leslie CS, Marks DS. Transfection of small RNAs globally perturbs gene regulation by endogenous microRNAs. Nat Biotechnol 2009. [PMID: 19465925 DOI: 10.1038/nbt0709-671a] [Citation(s) in RCA: 107] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Transfection of small RNAs (such as small interfering RNAs (siRNAs) and microRNAs (miRNAs)) into cells typically lowers expression of many genes. Unexpectedly, increased expression of genes also occurs. We investigated whether this upregulation results from a saturation effect--that is, competition among the transfected small RNAs and the endogenous pool of miRNAs for the intracellular machinery that processes small RNAs. To test this hypothesis, we analyzed genome-wide transcript responses from 151 published transfection experiments in seven different human cell types. We show that targets of endogenous miRNAs are expressed at significantly higher levels after transfection, consistent with impaired effectiveness of endogenous miRNA repression. This effect exhibited concentration and temporal dependence. Notably, the profile of endogenous miRNAs can be largely inferred by correlating miRNA sites with gene expression changes after transfections. The competition and saturation effects have practical implications for miRNA target prediction, the design of siRNA and short hairpin RNA (shRNA) genomic screens and siRNA therapeutics.
Collapse
Affiliation(s)
- Aly A Khan
- Department of Computer Science, Columbia University, New York, New York, USA
| | | | | | | | | | | |
Collapse
|
65
|
Aigner A. Transkingdom RNA interference (tkRNAi) as a new delivery tool for therapeutic RNA. Expert Opin Biol Ther 2009; 9:1533-42. [DOI: 10.1517/14712590903307354] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
66
|
Oh YK, Park TG. siRNA delivery systems for cancer treatment. Adv Drug Deliv Rev 2009; 61:850-62. [PMID: 19422869 DOI: 10.1016/j.addr.2009.04.018] [Citation(s) in RCA: 468] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Accepted: 04/28/2009] [Indexed: 02/07/2023]
Abstract
With increasing knowledge on the molecular mechanisms of endogenous RNA interference, small interfering RNAs (siRNAs) have been emerging as innovative nucleic acid medicines for treatment of incurable diseases such as cancers. Although several siRNA candidates for the treatment of ocular and respiratory diseases are undergoing clinical trials, there are challenges inherent in the further development of siRNAs for anti-cancer therapeutics, because systemic administration will be required in most cases. In addition to nonspecific off-target and immune stimulation problems, appropriate delivery remains a major hurdle. The technologies developed for delivery of nucleic acid medicines such as plasmid DNA and antisense oligonucleotides have paved the way to rapid progress for in vivo delivery of siRNAs. Here, we review various in vivo delivery strategies including chemical modification, conjugation, lipid-based techniques, polymer-based nanosystems, and physical methods. Moreover, the current progress in siRNA delivery systems for gynecologic, liver, lung, and prostate cancers is discussed.
Collapse
|
67
|
Rao DD, Vorhies JS, Senzer N, Nemunaitis J. siRNA vs. shRNA: similarities and differences. Adv Drug Deliv Rev 2009; 61:746-59. [PMID: 19389436 DOI: 10.1016/j.addr.2009.04.004] [Citation(s) in RCA: 403] [Impact Index Per Article: 26.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2009] [Accepted: 04/13/2009] [Indexed: 12/11/2022]
Abstract
RNA interference (RNAi) is a natural process through which expression of a targeted gene can be knocked down with high specificity and selectivity. Using available technology and bioinformatics investigators will soon be able to identify relevant bio molecular tumor network hubs as potential key targets for knockdown approaches. Methods of mediating the RNAi effect involve small interfering RNA (siRNA), short hairpin RNA (shRNA) and bi-functional shRNA. The simplicity of siRNA manufacturing and transient nature of the effect per dose are optimally suited for certain medical disorders (i.e. viral injections). However, using the endogenous processing machinery, optimized shRNA constructs allow for high potency and sustainable effects using low copy numbers resulting in less off-target effects, particularly if embedded in a miRNA scaffold. Bi-functional design may further enhance potency and safety of RNAi-based therapeutics. Remaining challenges include tumor selective delivery vehicles and more complete evaluation of the scope and scale of off-target effects. This review will compare siRNA, shRNA and bi-functional shRNA.
Collapse
|
68
|
Abstract
MicroRNAs (miRNAs) are non-protein-coding small RNA molecules that negatively regulate target messenger RNA through degradation or suppression of protein translation. MiRNAs play important roles in the control of many biologic processes, such as development, differentiation, proliferation, and apoptosis. Increasing evidence shows that aberrant miRNA expression profiles and unique miRNA signaling pathways are present in a variety of cancers. MiRNAs function as oncogenes or tumor suppressors during tumor development and progression. Experimental evidence demonstrates that correction of specific miRNA alterations using miRNA mimics or antagomirs can normalize the gene regulatory network and signaling pathways, and reverse the phenotype in cancerous cells. MiRNA-based gene therapy provides an attractive anti-tumor approach for integrated cancer therapy. In this review, we focus on miRNA-based treatment for cancers, summarize the delivery systems used in experimental and preclinical research, such as liposomes, viral vectors, and nanoparticles, and consider the safety and toxicity of miRNA therapy.
Collapse
Affiliation(s)
- Vivien Wang
- Department of Pathology, Evanston Northwestern Hospital, Evanston, Illinois, USA
| | | |
Collapse
|
69
|
Spurgers KB, Silvestri LS, Warfield KL, Bavari S. Toward RNA interference-based therapy for filovirus infections. Drug Dev Res 2009. [DOI: 10.1002/ddr.20302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
70
|
Abstract
The potential of harnessing RNA interference (RNAi) for sequence-specific gene silencing has generated much excitement and progress in the field. Recent advances in RNAi technology suggest that RNAi-based approaches may soon become an effective therapeutic strategy against a myriad of diseases. This overview provides a brief description of important considerations when designing an RNAi-based method for gene silencing and therapeutic development: (a) mechanistic aspects of RNAi-mediated gene silencing in mammalian cells; (b) structural requirements for potent siRNA duplexes; (c) off-target effects and interferon responses; and (d) effective delivery of RNAi-inducing agents. Promising therapeutic applications of RNAi that are currently in the developmental pipeline are also described.
Collapse
Affiliation(s)
- Daniel H Kim
- Howard Hughes Medical Institute, Department of Molecular Biology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | | |
Collapse
|
71
|
Langer R. A conversation with Robert Langer: pioneering biomedical scientist and engineer. Interview by Paul S. Weiss. ACS NANO 2009; 3:756-61. [PMID: 19397341 DOI: 10.1021/nn900350p] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
|
72
|
Li L, Shen Y. Overcoming obstacles to develop effective and safe siRNA therapeutics. Expert Opin Biol Ther 2009; 9:609-19. [DOI: 10.1517/14712590902911420] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Leiming Li
- siRNA Therapeutics, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, IL 60031, USA
| | - Yu Shen
- siRNA Therapeutics, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, IL 60031, USA
| |
Collapse
|
73
|
Tian W, Liou HC. RNAi-mediated c-Rel silencing leads to apoptosis of B cell tumor cells and suppresses antigenic immune response in vivo. PLoS One 2009; 4:e5028. [PMID: 19347041 PMCID: PMC2661141 DOI: 10.1371/journal.pone.0005028] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Accepted: 03/05/2009] [Indexed: 12/13/2022] Open
Abstract
c-Rel is a member of the Rel/NF-κB transcription factor family and is predominantly expressed in lymphoid and myeloid cells, playing a critical role in lymphocyte proliferation and survival. Persistent activation of the c-Rel signal transduction pathway is associated with allergies, inflammation, autoimmune diseases, and a variety of human malignancies. To explore the potential of targeting c-Rel as a therapeutic agent for these disorders, we designed a small interfering RNA (siRNA) to silence c-Rel expression in vitro and in vivo. C-Rel-siRNA expression via a retroviral vector in a B cell tumor cell line leads to growth arrest and apoptosis of the tumor cells. Silencing c-Rel in primary B cells in vitro compromises their proliferative and survival response to CD40 activation signals, similar to the impaired response of c-Rel knockout B cells. Most important, in vivo silencing of c-Rel results in significant impairment in T cell-mediated immune responses to antigenic stimulation. Our study thus validates the efficacy of c-Rel-siRNA, and suggests the development of siRNA-based therapy, as well as small molecular inhibitors for the treatment of B cell tumors as well as autoimmune diseases.
Collapse
Affiliation(s)
- Wenzhi Tian
- Division of Immunology, Department of Medicine, Weill Medical College of Cornell University, New York, New York, United States of America
| | - Hsiou-Chi Liou
- Division of Immunology, Department of Medicine, Weill Medical College of Cornell University, New York, New York, United States of America
- * E-mail:
| |
Collapse
|
74
|
Abstract
An efficient mechanism for the sequence‐specific inhibition of gene expression is RNA interference. In this process, double‐stranded RNA molecules induce cleavage of a selected target RNA (see picture). This technique has in recent years developed into a standard method of molecular biology. Successful applications in animal models have already led to the initiation of RNAi‐based clinical trials as a new therapeutic option.WILEY-VCH Only ten years ago Andrew Fire and Craig Mello were able to show that double‐stranded RNA molecules could inhibit the expression of homologous genes in eukaryotes. This process, termed RNA interference, has developed into a standard method of molecular biology. This Review provides an overview of the molecular processes involved, with a particular focus on the posttranscriptional inhibition of gene expression in mammalian cells, the possible applications in research, and the results of the first clinical studies.
Collapse
Affiliation(s)
- Jens Kurreck
- Institute of Industrial Genetics, University of Stuttgart, Allmandring 31, 70569 Stuttgart, Germany.
| |
Collapse
|
75
|
Whitehead KA, Langer R, Anderson DG. Knocking down barriers: advances in siRNA delivery. Nat Rev Drug Discov 2009. [PMID: 19180106 DOI: 10.1038/nrd3182] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In the 10 years that have passed since the Nobel prize-winning discovery of RNA interference (RNAi), billions of dollars have been invested in the therapeutic application of gene silencing in humans. Today, there are promising data from ongoing clinical trials for the treatment of age-related macular degeneration and respiratory syncytial virus. Despite these early successes, however, the widespread use of RNAi therapeutics for disease prevention and treatment requires the development of clinically suitable, safe and effective drug delivery vehicles. Here, we provide an update on the progress of RNAi therapeutics and highlight novel synthetic materials for the encapsulation and intracellular delivery of nucleic acids.
Collapse
Affiliation(s)
- Kathryn A Whitehead
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | | | | |
Collapse
|
76
|
Abstract
RNA interference (RNAi) is a fundamental pathway in eukaryotic cells by which sequence-specific small interfering RNA (siRNA) is able to silence genes through the destruction of complementary mRNA. RNAi is an important therapeutic tool that can be used to silence aberrant endogenous genes or to knockdown genes essential to the proliferation of infectious organisms. Delivery remains the central challenge to the therapeutic application of RNAi technology. Before siRNA can take effect in the cytoplasm of a target cell, it must be transported through the body to the target site without undergoing clearance or degradation. Currently, the most effective synthetic, non-viral delivery agents of siRNA are lipids, lipid-like materials and polymers. Various cationic agents including stable nucleic acid–lipid particles, lipidoids, cyclodextrin polymers and polyethyleneimine polymers have been used to achieve the successful systemic delivery of siRNA in mammals without inducing significant toxicity. Direct conjugation of delivery agents to siRNA can facilitate delivery. For example, cholesterol-modified siRNA enables targeting to the liver. RNAi therapeutics have progressed to the clinic, where studies are being conducted to determine siRNA efficacy in treating several diseases, including age-related macular degeneration and respiratory syncytial virus. Moving forward, it will be important to pay close attention to the potential nonspecific immunostimulatory effects of siRNA. Modifications to siRNA can be used to minimize stimulation of the immune system, and an increased emphasis must be placed on performing proper controls to ensure that therapeutic effects are sequence-specific.
RNA interference holds vast potential as a therapeutic strategy for both disease prevention and treatment, but its use has so far been hampered by a lack of safe and effective delivery techniques. In their Review, Anderson and colleagues discuss the challenges associated with small interfering RNA delivery and highlight promising novel synthetic delivery agents. In the 10 years that have passed since the Nobel prize-winning discovery of RNA interference (RNAi), billions of dollars have been invested in the therapeutic application of gene silencing in humans. Today, there are promising data from ongoing clinical trials for the treatment of age-related macular degeneration and respiratory syncytial virus. Despite these early successes, however, the widespread use of RNAi therapeutics for disease prevention and treatment requires the development of clinically suitable, safe and effective drug delivery vehicles. Here, we provide an update on the progress of RNAi therapeutics and highlight novel synthetic materials for the encapsulation and intracellular delivery of nucleic acids.
Collapse
Affiliation(s)
- Kathryn A Whitehead
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | | | | |
Collapse
|
77
|
Burchard J, Jackson AL, Malkov V, Needham RHV, Tan Y, Bartz SR, Dai H, Sachs AB, Linsley PS. MicroRNA-like off-target transcript regulation by siRNAs is species specific. RNA (NEW YORK, N.Y.) 2009; 15:308-15. [PMID: 19144911 PMCID: PMC2648714 DOI: 10.1261/rna.1326809] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
siRNAs mediate sequence-specific gene silencing in cultured mammalian cells but also silence unintended transcripts. Many siRNA off-target transcripts match the guide-strand "seed region," similar to the way microRNAs match their target sites. The extent to which this seed-matched, microRNA-like, off-target silencing affects the specificity of therapeutic siRNAs in vivo is currently unknown. Here, we compare microRNA-like off-target regulations in mouse liver in vivo with those seen in cell culture for a series of therapeutic candidate siRNAs targeting Apolipoprotein B (APOB). Each siRNA triggered regulation of consistent microRNA-like off-target transcripts in mouse livers and in cultured mouse liver tumor cells. In contrast, there was only random overlap between microRNA-like off-target transcripts from cultured human and mouse liver tumor cells. Therefore, siRNA therapeutics may trigger microRNA-like silencing of many unintended targets in vivo, and the potential toxicities caused by these off-target gene regulations cannot be accurately assessed in rodent models.
Collapse
Affiliation(s)
- Julja Burchard
- Rosetta Inpharmatics LLC, Seattle, Washington 98109, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
78
|
Affiliation(s)
- Jens Kurreck
- Institut für Industrielle Genetik, Universität Stuttgart, Allmandring 31, 70569 Stuttgart (Deutschland), Fax: (+49) 711‐685 66973 http://www.uni‐stuttgart.de/iig/institut/staff/kurreck/index.html
| |
Collapse
|
79
|
Jere D, Kim JE, Arote R, Jiang HL, Kim YK, Choi YJ, Yun CH, Cho MH, Cho CS. Akt1 silencing efficiencies in lung cancer cells by sh/si/ssiRNA transfection using a reductable polyspermine carrier. Biomaterials 2008; 30:1635-47. [PMID: 19097641 DOI: 10.1016/j.biomaterials.2008.12.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Accepted: 12/01/2008] [Indexed: 12/19/2022]
Abstract
Efforts directed in ameliorating silencing studies with shRNA, siRNA and ssiRNA (siRNA with sticky overhangs) are faltered mainly due to the lack of efficient carrier system. In the present study, we developed reductable polyspermine (RPS) carrier composed of multiple spermine units with disulfide linkages for gene expression and silencing studies. In gene expression studies, EGFP expression was found to be almost 4 folds higher and 20 folds safer with RPS carrier than with PEI25K. Moreover, on systemic administration, RPS exhibited significantly high EGFP expression in mice lungs. Similarly in gene silencing studies, EGFP silencing achieved was nearly 1.5 times superior with RPS carrier than PEI25K. Also, RPS delivered Akt1 shRNA (shAkt), siRNA (siAkt) and ssiRNA (ssiAkt) efficiently silenced oncoprotein Akt1 and thereby decreased A549 cell survival. The degrees of cell survival, proliferation and metastasis were differed with the nature of siRNA treatment. Further study at different time intervals revealed that ssiAkt treatment, although superior to sh/siAkt, was highly transient while, shAkt treatment was uniform and prolong. These finding demonstrate the potential use of RPS carrier in gene expression and silencing studies, and significance of the nature of siRNA employed in cancer study.
Collapse
Affiliation(s)
- Dhananjay Jere
- Department of Agricultural Biotechnology, Seoul National University, Seoul, Republic of Korea
| | | | | | | | | | | | | | | | | |
Collapse
|
80
|
Prudêncio M, Rodrigues CD, Hannus M, Martin C, Real E, Gonçalves LA, Carret C, Dorkin R, Röhl I, Jahn-Hoffmann K, Luty AJF, Sauerwein R, Echeverri CJ, Mota MM. Kinome-wide RNAi screen implicates at least 5 host hepatocyte kinases in Plasmodium sporozoite infection. PLoS Pathog 2008; 4:e1000201. [PMID: 18989463 PMCID: PMC2574010 DOI: 10.1371/journal.ppat.1000201] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2008] [Accepted: 10/13/2008] [Indexed: 12/21/2022] Open
Abstract
Plasmodium sporozoites, the causative agent of malaria, are injected into their vertebrate host through the bite of an infected Anopheles mosquito, homing to the liver where they invade hepatocytes to proliferate and develop into merozoites that, upon reaching the bloodstream, give rise to the clinical phase of infection. To investigate how host cell signal transduction pathways affect hepatocyte infection, we used RNAi to systematically test the entire kinome and associated genes in human Huh7 hepatoma cells for their potential roles during infection by P. berghei sporozoites. The three-phase screen covered 727 genes, which were tested with a total of 2,307 individual siRNAs using an automated microscopy assay to quantify infection rates and qRT-PCR to assess silencing levels. Five protein kinases thereby emerged as top hits, all of which caused significant reductions in infection when silenced by RNAi. Follow-up validation experiments on one of these hits, PKCς (PKCzeta), confirmed the physiological relevance of our findings by reproducing the inhibitory effect on P. berghei infection in adult mice treated systemically with liposome-formulated PKCς-targeting siRNAs. Additional cell-based analyses using a pseudo-substrate inhibitor of PKCς added further RNAi-independent support, indicating a role for host PKCς on the invasion of hepatocytes by sporozoites. This study represents the first comprehensive, functional genomics-driven identification of novel host factors involved in Plasmodium sporozoite infection. During a mammalian malaria infection, Plasmodium sporozoites injected by an infected mosquito travel to the liver where they invade hepatocytes and multiply into thousands of new parasites. These newly formed merozoites are then released into the bloodstream where they infect red blood cells and cause the symptoms of the disease. Although asymptomatic, the liver stage of malaria is an obligatory step in the parasite's lifecycle and constitutes an appealing target for prophylatic intervention. The marked tropism of sporozoites for hepatocytes suggests the latter may provide the parasite with a molecular environment that it can exploit to its own benefit. The identification of host factors that influence hepatic infection can thus provide clues for potential anti-malarial strategies. To this end, we carried out an RNA interference screen of the entire human kinome and associated signaling molecules and assessed the effect of knockdown of their expression in the infection of a human hepatoma cell line by Plasmodium. This strategy identified at least 5 kinases whose down-regulation leads to a marked decrease in infection. Further characterisation of one of these proteins, PKCζ, confirmed that it plays a role in infection by influencing the parasite's invasion of the host liver cells.
Collapse
Affiliation(s)
- Miguel Prudêncio
- Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | - Cristina D. Rodrigues
- Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
| | | | | | - Eliana Real
- Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal
| | | | - Céline Carret
- Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal
| | - Robert Dorkin
- Alnylam Pharmaceuticals, Cambridge, Massachusetts, United States of America
| | - Ingo Röhl
- Roche Kulmbach GmbH, Kulmbach, Germany
| | | | - Adrian J. F. Luty
- Department of Medical Microbiology, University Medical Centre, Nijmegen, The Netherlands
| | - Robert Sauerwein
- Department of Medical Microbiology, University Medical Centre, Nijmegen, The Netherlands
| | | | - Maria M. Mota
- Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, Lisboa, Portugal
- Instituto Gulbenkian de Ciência, Oeiras, Portugal
- * E-mail:
| |
Collapse
|
81
|
Rodrigues CD, Hannus M, Prudêncio M, Martin C, Gonçalves LA, Portugal S, Epiphanio S, Akinc A, Hadwiger P, Jahn-Hofmann K, Röhl I, van Gemert GJ, Franetich JF, Luty AJF, Sauerwein R, Mazier D, Koteliansky V, Vornlocher HP, Echeverri CJ, Mota MM. Host scavenger receptor SR-BI plays a dual role in the establishment of malaria parasite liver infection. Cell Host Microbe 2008; 4:271-82. [PMID: 18779053 DOI: 10.1016/j.chom.2008.07.012] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2008] [Revised: 06/27/2008] [Accepted: 07/18/2008] [Indexed: 12/29/2022]
Abstract
An obligatory step of malaria parasite infection is Plasmodium sporozoite invasion of host hepatocytes, and host lipoprotein clearance pathways have been linked to Plasmodium liver infection. By using RNA interference to screen lipoprotein-related host factors, we show here that the class B, type I scavenger receptor (SR-BI) is the strongest regulator of Plasmodium infection among these factors. Inhibition of SR-BI function reduced P. berghei infection in Huh7 cells, and overexpression of SR-BI led to increased infection. In vivo silencing of liver SR-BI expression in mice and inhibition of SR-BI activity in human primary hepatocytes reduced infection by P. berghei and by P. falciparum, respectively. Heterozygous SR-BI(+/-) mice displayed reduced P. berghei infection rates correlating with liver SR-BI expression levels. Additional analyses revealed that SR-BI plays a dual role in Plasmodium infection, affecting both sporozoite invasion and intracellular parasite development, and may therefore constitute a good target for malaria prophylaxis.
Collapse
Affiliation(s)
- Cristina D Rodrigues
- Unidade de Malária, Instituto de Medicina Molecular, Universidade de Lisboa, 1649-028 Lisboa, Portugal
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
82
|
Chen Y, Yan T, Shi LJ, Liu Z, Liang SY, Luan XF, Long FW, Chen J, Peng Y, Yan LN, Gong JP. Knockdown of interleukin-2 by shRNA-mediated RNA interference prolongs liver allograft survival. J Surg Res 2008; 159:582-7. [PMID: 19589546 DOI: 10.1016/j.jss.2008.09.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Revised: 08/20/2008] [Accepted: 09/16/2008] [Indexed: 10/21/2022]
Abstract
Interleukin-2 (IL-2) plays a central role in T-cell activation, expansion, and homeostasis. The failure of IL-2 biosynthesis may play a critical role in tolerance induction. We tested the effect of IL-2 blockade by short hairpin RNA (shRNA) on regulating acute rejection in rat liver transplantation. To this end, we successfully designed and selected an effective interference plasmid, pIL-2B. The IL-2 mRNA expression level in the pIL-2B group was one-fifth of that in the no transfection group. Lewis to BN orthotopic liver transplant model was used to explore the effect of knockdown IL-2 by shRNA in vivo. Recipients treated with pIL-2-shRNA survived longer (median survival time of 16 d range 7-21 d) than those with empty vector (11; range 5-13) or saline (9; range 5-13) (P<0.05), and was inferior to those with CsA (24; range 13-36, P<0.05). The IL-2-shRNA attenuated acute rejection with decreased apoptosis of hepatocytes and reduced cytokine production of IL-2, tumor necrosis factor-alpha (TNF-alpha), and interferon-gamma (IFN-gamma) in the graft. Our results suggest that IL-2 targeting using RNA interference approach may be of potential interest in organ transplantation.
Collapse
Affiliation(s)
- Yong Chen
- Chongqing Key Laboratory of Hepatobliliary Surgery and Department of Hepatobliliary Surgery, Second Affiliated Hospital, Chongqing Medical University, Chongqing, PR China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
83
|
Abstract
Therapeutic options against the human immunodeficiency virus type 1 (HIV-1) continue to expand with the development of new drugs and new therapeutic strategies. Nevertheless, management of HIV-1 infected individuals has become increasingly complex. The emergence of drug-resistant variants, the growing recognition of the long-term toxicity of antiretroviral therapies and the persistence of viral reservoirs justify the continued efforts to develop new anti-HIV-1 strategies. Recent advances regarding the utility of RNA-mediated interference (RNAi) to specifically inhibit HIV-1 replication have opened new possibilities for the development of gene-based therapies against HIV-1 infection. Here, the recent advances in siRNA-based therapies are reviewed.
Collapse
|
84
|
Abstract
A significant barrier to the successful general development of small-interfering RNA (siRNA) therapeutics is the ability to deliver them systemically to target organs and cell types. In this study, we have developed a mouse strain that will facilitate the evaluation of the efficacy of siRNA delivery strategies. This strain contains robust ubiquitous expression of firefly luciferase from germ line Cre-mediated recombination of the ROSA26-LSL-Luc allele. We show that luciferase is highly and uniformly expressed in all tissues examined. Using this mouse model, we describe a facile assay that enables the assessment of the pharmacodynamics of a systemically delivered siRNA formulation. These mice can also be used as universal donors, enabling the efficient and sensitive monitoring of cell trafficking or tissue transplantation. The primary advantage of this approach is that siRNA efficacy against a nonessential target can be easily evaluated in any tissue. This strain should generally enhance the ability to rapidly screen, compare and optimize various siRNA formulations for tissue-targeted or -enhanced systemic delivery in a preclinical development setting.
Collapse
|
85
|
Lindsay MA. microRNAs and the immune response. Trends Immunol 2008; 29:343-51. [PMID: 18515182 DOI: 10.1016/j.it.2008.04.004] [Citation(s) in RCA: 434] [Impact Index Per Article: 27.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2007] [Revised: 04/17/2008] [Accepted: 04/18/2008] [Indexed: 12/13/2022]
Abstract
microRNA (miRNA)-mediated RNA interference has been identified as a novel mechanism that regulates protein expression at the translational level. Recent publications have provided compelling evidence that a range of miRNAs are involved in the regulation of immunity, including the development and differentiation of B and T cells, proliferation of monocytes and neutrophils, antibody switching and the release of inflammatory mediators. In this review, we examine what is presently known of the function and mechanism of action of these miRNAs in the regulation of the innate and acquired immune response.
Collapse
Affiliation(s)
- Mark A Lindsay
- Respiratory Research Group, Wythenshawe Hospital, School of Translational Sciences, University of Manchester M23 9LT, UK.
| |
Collapse
|
86
|
Kumar P, Ban HS, Kim SS, Wu H, Pearson T, Greiner DL, Laouar A, Yao J, Haridas V, Habiro K, Yang YG, Jeong JH, Lee KY, Kim YH, Kim SW, Peipp M, Fey GH, Manjunath N, Shultz LD, Lee SK, Shankar P. T cell-specific siRNA delivery suppresses HIV-1 infection in humanized mice. Cell 2008; 134:577-86. [PMID: 18691745 PMCID: PMC2943428 DOI: 10.1016/j.cell.2008.06.034] [Citation(s) in RCA: 455] [Impact Index Per Article: 28.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2008] [Revised: 05/08/2008] [Accepted: 06/12/2008] [Indexed: 11/17/2022]
Abstract
Evaluation of the therapeutic potential of RNAi for HIV infection has been hampered by the challenges of siRNA delivery and lack of suitable animal models. Using a delivery method for T cells, we show that siRNA treatment can dramatically suppress HIV infection. A CD7-specific single-chain antibody was conjugated to oligo-9-arginine peptide (scFvCD7-9R) for T cell-specific siRNA delivery in NOD/SCIDIL2rgamma-/- mice reconstituted with human lymphocytes (Hu-PBL) or CD34+ hematopoietic stem cells (Hu-HSC). In HIV-infected Hu-PBL mice, treatment with anti-CCR5 (viral coreceptor) and antiviral siRNAs complexed to scFvCD7-9R controlled viral replication and prevented the disease-associated CD4 T cell loss. This treatment also suppressed endogenous virus and restored CD4 T cell counts in mice reconstituted with HIV+ peripheral blood mononuclear cells. Moreover, scFvCD7-9R could deliver antiviral siRNAs to naive T cells in Hu-HSC mice and effectively suppress viremia in infected mice. Thus, siRNA therapy for HIV infection appears to be feasible in a preclinical animal model.
Collapse
Affiliation(s)
- Priti Kumar
- Immune Disease Institute and Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | - Hong-Seok Ban
- Department of Bioengineering and Hanyang Fusion Materials Program,, Hanyang University, Seoul, 133-791, Korea
| | - Sang-Soo Kim
- Immune Disease Institute and Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | - Haoquan Wu
- Immune Disease Institute and Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | - Todd Pearson
- Department of Medicine, Division of Diabetes, University of Massachusetts Medical School, Worcester, 01605, MA, USA
| | - Dale. L. Greiner
- Department of Medicine, Division of Diabetes, University of Massachusetts Medical School, Worcester, 01605, MA, USA
| | - Amale Laouar
- Immune Disease Institute and Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | - Jiahong Yao
- Immune Disease Institute and Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | - Viraga Haridas
- Immune Disease Institute and Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | - Katsuyoshi Habiro
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - Yong-Guang Yang
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA, 02129, USA
| | - Ji-Hoon Jeong
- Center for Controlled Chemical Delivery, Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT, 84112, USA
| | - Kuen-Yong Lee
- Department of Bioengineering and Hanyang Fusion Materials Program,, Hanyang University, Seoul, 133-791, Korea
| | - Yong-Hee Kim
- Department of Bioengineering and Hanyang Fusion Materials Program,, Hanyang University, Seoul, 133-791, Korea
| | - Sung Wan Kim
- Center for Controlled Chemical Delivery, Department of Pharmaceutics and Pharmaceutical Chemistry, University of Utah, Salt Lake City, UT, 84112, USA
| | - Matthias Peipp
- Division of Stem Cell Transplantation and Immunotherapy, Christian-Albrechts-University, Kiel, Germany
| | - Georg H. Fey
- University of Erlangen, D 91058, Erlangen, Germany
| | - N Manjunath
- Immune Disease Institute and Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| | | | - Sang-Kyung Lee
- Department of Bioengineering and Hanyang Fusion Materials Program,, Hanyang University, Seoul, 133-791, Korea
| | - Premlata Shankar
- Immune Disease Institute and Department of Pediatrics, Harvard Medical School, Boston, MA, 02115, USA
| |
Collapse
|
87
|
Therapeutic RNAi targeting PCSK9 acutely lowers plasma cholesterol in rodents and LDL cholesterol in nonhuman primates. Proc Natl Acad Sci U S A 2008; 105:11915-20. [PMID: 18695239 DOI: 10.1073/pnas.0805434105] [Citation(s) in RCA: 490] [Impact Index Per Article: 30.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Proprotein convertase subtilisin/kexin type 9 (PCSK9) regulates low density lipoprotein receptor (LDLR) protein levels and function. Loss of PCSK9 increases LDLR levels in liver and reduces plasma LDL cholesterol (LDLc), whereas excess PCSK9 activity decreases liver LDLR levels and increases plasma LDLc. Here, we have developed active, cross-species, small interfering RNAs (siRNAs) capable of targeting murine, rat, nonhuman primate (NHP), and human PCSK9. For in vivo studies, PCSK9 and control siRNAs were formulated in a lipidoid nanoparticle (LNP). Liver-specific siRNA silencing of PCSK9 in mice and rats reduced PCSK9 mRNA levels by 50-70%. The reduction in PCSK9 transcript was associated with up to a 60% reduction in plasma cholesterol concentrations. These effects were shown to be mediated by an RNAi mechanism, using 5'-RACE. In transgenic mice expressing human PCSK9, siRNAs silenced the human PCSK9 transcript by >70% and significantly reduced PCSK9 plasma protein levels. In NHP, a single dose of siRNA targeting PCSK9 resulted in a rapid, durable, and reversible lowering of plasma PCSK9, apolipoprotein B, and LDLc, without measurable effects on either HDL cholesterol (HDLc) or triglycerides (TGs). The effects of PCSK9 silencing lasted for 3 weeks after a single bolus i.v. administration. These results validate PCSK9 targeting with RNAi therapeutics as an approach to specifically lower LDLc, paving the way for the development of PCSK9-lowering agents as a future strategy for treatment of hypercholesterolemia.
Collapse
|
88
|
Raemdonck K, Vandenbroucke RE, Demeester J, Sanders NN, De Smedt SC. Maintaining the silence: reflections on long-term RNAi. Drug Discov Today 2008; 13:917-31. [PMID: 18620073 PMCID: PMC7108305 DOI: 10.1016/j.drudis.2008.06.008] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 05/16/2008] [Accepted: 06/06/2008] [Indexed: 10/26/2022]
Abstract
Since the demonstration of RNA interference (RNAi) in mammalian cells, considerable research and financial effort has gone towards implementing RNAi as a viable therapeutic platform. RNAi is, without doubt, the most promising strategy for the treatment of human genetic disorders. Because many of the targets proposed for RNAi therapy require chronic treatment, researchers agree that the emphasis must now be placed on the safe and long-term application of RNAi drugs to reap the benefits at last.
Collapse
Affiliation(s)
- Koen Raemdonck
- Laboratory of General Biochemistry and Physical Pharmacy, Faculty of Pharmaceutical Sciences, Ghent University, Harelbekestraat 72, B-9000 Ghent, Belgium
| | | | | | | | | |
Collapse
|
89
|
Affiliation(s)
- Dirk Haussecker
- Department of Pediatrics, Stanford School of Medicine, Stanford, CA 94305, USA.
| |
Collapse
|
90
|
Charchar FJ, Zimmerli LU, Tomaszewski M. The pressure of finding human hypertension genes: new tools, old dilemmas. J Hum Hypertens 2008; 22:821-8. [DOI: 10.1038/jhh.2008.67] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
91
|
Wang H, Ghosh A, Baigude H, Yang CS, Qiu L, Xia X, Zhou H, Rana TM, Xu Z. Therapeutic gene silencing delivered by a chemically modified small interfering RNA against mutant SOD1 slows amyotrophic lateral sclerosis progression. J Biol Chem 2008; 283:15845-52. [PMID: 18367449 PMCID: PMC2414310 DOI: 10.1074/jbc.m800834200] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2008] [Revised: 03/17/2008] [Indexed: 02/01/2023] Open
Abstract
Inherited neurodegenerative diseases, such as Huntington disease and subset of Alzheimer disease, Parkinson disease, and amyotrophic lateral sclerosis, are caused by the mutant genes that have gained undefined properties that harm cells in the nervous system, causing neurodegeneration and clinical phenotypes. Lowering the mutant gene expression is predicted to slow the disease progression and produce clinical benefit. Administration of small interfering RNA (siRNA) can silence specific genes. However, long term delivery of siRNA to silence the mutant genes, a requirement for treatment of these chronic central nervous system (CNS) diseases, remains a critical unsolved issue. Here we designed and tested a chemically stabilized siRNA against human Cu,Zn-superoxide dismutase (SOD1) in a mouse model for amyotrophic lateral sclerosis. We show that the modified siRNA has enhanced stability and retains siRNA activity. Administration of this siRNA at the disease onset by long term infusion into the CNS resulted in widespread distribution of this siRNA, knocked down the mutant SOD1 expression, slowed the disease progression, and extended the survival. These results bring RNA interference therapy one step closer to its clinical application for treatment of chronic, devastating, and fatal CNS disorders.
Collapse
Affiliation(s)
- Hongyan Wang
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| | - Animesh Ghosh
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| | - Huricha Baigude
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| | - Chao-shun Yang
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| | - Linghua Qiu
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| | - Xugang Xia
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| | - Hongxia Zhou
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| | - Tariq M. Rana
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| | - Zuoshang Xu
- Department of Biochemistry and Molecular
Pharmacology, Chemical Biology Program,
Cell Biology, and
Neuroscience Program, University of Massachusetts
Medical School, Worcester, Massachusetts 01605
| |
Collapse
|
92
|
Huang C, Li M, Chen C, Yao Q. Small interfering RNA therapy in cancer: mechanism, potential targets, and clinical applications. Expert Opin Ther Targets 2008; 12:637-45. [PMID: 18410245 DOI: 10.1517/14728222.12.5.637] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Small interfering RNA (siRNA) has become a powerful tool in knocking down or silencing gene expression in most cells. siRNA-based therapy has shown great promise for many diseases such as cancer. Major targets for siRNA therapy include oncogenes and genes that are involved in angiogenesis, metastasis, survival, antiapoptosis and resistance to chemotherapy. OBJECTIVES This review briefly summarizes current advances in siRNA therapy and clinical applications in cancers, especially in pancreatic cancer. METHODS This review article covers several aspects of siRNA therapy in cancer, which include the types of siRNA, the delivery systems for siRNA, and the major targets for siRNA therapy. Specific attention is given to siRNA in pancreatic cancer, which is our main research focus. RESULTS/CONCLUSION siRNA can be introduced into the cells by using either chemically synthesized siRNA oligonucleotides (oligos), or vector-based siRNA (shRNA), which allows long lasting and more stable gene silencing. Nanoparticles and liposomes are commonly used carriers, delivering the siRNA with better transfection efficiency and protecting it from degradation. In combination with standard chemotherapy, siRNA therapy can also reduce the chemoresistance of certain cancers, demonstrating the potential of siRNA therapy for treating many malignant diseases. This review will provide valuable information for clinicians and researchers who want to recognize the newest endeavors within this field and identify possible lines of investigation in cancer.
Collapse
Affiliation(s)
- Chuan Huang
- Michael E. DeBakey Department of Surgery, Baylor College of Medicine, Houston, Texas 77030, USA
| | | | | | | |
Collapse
|
93
|
de Fougerolles A, Novobrantseva T. siRNA and the lung: research tool or therapeutic drug? Curr Opin Pharmacol 2008; 8:280-5. [PMID: 18485820 PMCID: PMC7106383 DOI: 10.1016/j.coph.2008.04.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2008] [Revised: 04/07/2008] [Accepted: 04/08/2008] [Indexed: 11/15/2022]
Abstract
Oligonucleotide-based therapeutics have been hailed as ‘the next great wave of the biotechnology revolution’ starting with antisense oligonucleotides (ASOs) nearly 20 years ago to RNA interference (RNAi) currently. Is RNAi just the latest research tool or does it have real potential as a therapeutic drug modality? As a research tool, it is evident that RNAi has revolutionized the biological sciences by allowing selective silencing of messenger RNA (mRNA) expression. With the advent of the postgenomic era, RNAi offers a therapeutic platform on which to identify potential picomolar active drug candidates to any target, including those that are conventionally undruggable. In this review, we will discuss the progress made in developing RNAi therapeutics for the treatment of respiratory diseases.
Collapse
|
94
|
|
95
|
Marquez RT, McCaffrey AP. Advances in microRNAs: implications for gene therapists. Hum Gene Ther 2008; 19:27-38. [PMID: 18092919 DOI: 10.1089/hum.2007.147] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
MicroRNAs (miRNAs) are a class of small regulatory RNAs that are thought to regulate the expression of as many as one-third of all human messenger RNAs (mRNAs). miRNAs are thought to be involved in diverse biological processes, including tumorigenesis. Analysis of miRNA levels may have diagnostic implications. Evidence shows that numerous viruses interact with the miRNA machinery, and that a number of viruses encode their own miRNAs. It seems likely that miRNAs will be implicated in many human diseases. Manipulation of miRNA levels by gene therapy provides an attractive new approach for therapeutic development. This review focuses on approaches to manipulate miRNA levels in cells and in vivo, and the implications for gene therapy. Furthermore, we discuss the use of endogenous miRNAs as scaffolds for the expression of RNA interference (RNAi) as well as competition between exogenous RNAi triggers and endogenous miRNAs. Because short interfering RNAs can also act as miRNAs, seed matches with the 3' untranslated regions of genes should be avoided to prevent off-target effects. Last, we discuss the use of miRNAs to avoid immune responses to viral vectors.
Collapse
Affiliation(s)
- Rebecca T Marquez
- Department of Internal Medicine, University of Iowa, Iowa City, IA 52242, USA
| | | |
Collapse
|
96
|
Zhao XF, Fjose A, Larsen N, Helvik JV, Drivenes Ø. Treatment with small interfering RNA affects the microRNA pathway and causes unspecific defects in zebrafish embryos. FEBS J 2008; 275:2177-84. [PMID: 18384379 DOI: 10.1111/j.1742-4658.2008.06371.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
MicroRNAs (miRNAs) are generated from primary transcripts through sequential processing by two RNase III enzymes, Drosha and Dicer, in association with other proteins. This maturation is essential for their function as post-transcriptional regulators. Notably, Dicer is also a component of RNA-induced silencing complexes, which incorporate either miRNA or small interfering RNA (siRNA) as guides to target specific mRNAs. In zebrafish, processed miRNAs belonging to the miR-430 family have previously been shown to promote deadenylation and degradation of maternal mRNAs during early embryogenesis. We show that injection of one-cell-stage zebrafish embryos with siRNA causes a significant reduction in the endogenous levels of processed miR-430 and other miRNAs, leading to unspecific developmental defects. Coinjection of siRNA with preprocessed miR-430 efficiently rescued development. This indicates that the abnormalities generally observed in siRNA-treated zebrafish embryos could be due to inhibition of miR-430 processing and/or activity. Our results also suggest that the miRNA pathway in mammals, under some experimental or therapeutic conditions, may be affected by siRNA.
Collapse
Affiliation(s)
- Xiao-Feng Zhao
- Department of Molecular Biology, University of Bergen, Norway
| | | | | | | | | |
Collapse
|
97
|
Arbuthnot P, Thompson LJ. Harnessing the RNA interference pathway to advance treatment and prevention of hepatocellular carcinoma. World J Gastroenterol 2008; 14:1670-81. [PMID: 18350598 PMCID: PMC2695907 DOI: 10.3748/wjg.14.1670] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/04/2007] [Revised: 01/27/2008] [Indexed: 02/06/2023] Open
Abstract
Primary liver cancer is the fifth most common malignancy in the world and is a leading cause of cancer-related mortality. Available treatment for hepatocellular carcinoma (HCC), the commonest primary liver cancer, is rarely curative and there is a need to develop therapy that is more effective. Specific and powerful gene silencing that can be achieved by activating RNA interference (RNAi) has generated enthusiasm for exploiting this pathway for HCC therapy. Many studies have been carried out with the aim of silencing HCC-related cellular oncogenes or the hepatocarcinogenic hepatitis B virus (HBV) and hepatitis C virus (HCV). Proof of principle studies have demonstrated promising results, and an early clinical trial assessing RNAi-based HBV therapy is currently in progress. Although the data augur well, there are several significant hurdles that need to be overcome before the goal of RNAi-based therapy for HCC is realized. Particularly important are the efficient and safe delivery of RNAi effecters to target malignant tissue and the limitation of unintended harmful non-specific effects.
Collapse
|
98
|
|
99
|
McSwiggen JA, Seth S. A potential treatment for pandemic influenza using siRNAs targeting conserved regions of influenza A. Expert Opin Biol Ther 2008; 8:299-313. [DOI: 10.1517/14712598.8.3.299] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
|
100
|
Corey DR. Chemical modification: the key to clinical application of RNA interference? J Clin Invest 2008; 117:3615-22. [PMID: 18060019 DOI: 10.1172/jci33483] [Citation(s) in RCA: 221] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
RNA interference provides a potent and specific method for controlling gene expression in human cells. To translate this potential into a broad new family of therapeutics, it is necessary to optimize the efficacy of the RNA-based drugs. As discussed in this Review, it might be possible to achieve this optimization using chemical modifications that improve their in vivo stability, cellular delivery, biodistribution, pharmacokinetics, potency, and specificity.
Collapse
Affiliation(s)
- David R Corey
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9041, USA.
| |
Collapse
|