1
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Bento C, Katz M, Santos MMM, Afonso CAM. Striving for Uniformity: A Review on Advances and Challenges To Achieve Uniform Polyethylene Glycol. Org Process Res Dev 2024; 28:860-890. [PMID: 38660381 PMCID: PMC11036406 DOI: 10.1021/acs.oprd.3c00428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2023] [Revised: 03/01/2024] [Accepted: 03/08/2024] [Indexed: 04/26/2024]
Abstract
Poly(ethylene glycol) (PEG) is the polymer of choice in drug delivery systems due to its biocompatibility and hydrophilicity. For over 20 years, this polymer has been widely used in the drug delivery of small drugs, proteins, oligonucleotides, and liposomes, improving the stability and pharmacokinetics of many drugs. However, despite the extensive clinical experience with PEG, concerns have emerged related to its use. These include hypersensitivity, purity, and nonbiodegradability. Moreover, conventional PEG is a mixture of polymers that can complicate drug synthesis and purification leading to unwanted immunogenic reactions. Studies have shown that uniform PEGylated drugs may be more effective than conventional PEGylated drugs as they can overcome issues related to molecular heterogeneity and immunogenicity. This has led to significant research efforts to develop synthetic procedures to produce uniform PEGs (monodisperse PEGs). As a result, iterative step-by-step controlled synthesis methods have been created over time and have shown promising results. Nonetheless, these procedures have presented numerous challenges due to their iterative nature and the requirement for multiple purification steps, resulting in increased costs and time consumption. Despite these challenges, the synthetic procedures went through several improvements. This review summarizes and discusses recent advances in the synthesis of uniform PEGs and its derivatives with a focus on overall yields, scalability, and purity of the polymers. Additionally, the available characterization methods for assessing polymer monodispersity are discussed as well as uniform PEG applications, side effects, and possible alternative polymers that can overcome the drawbacks.
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Affiliation(s)
- Cláudia Bento
- Hovione
Farmaciência S.A., Estrada do Paço do Lumiar, Campus do Lumiar, Edifício
R, 1649-038 Lisboa, Portugal
- Research
Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Avenida Professor Gama Pinto, 1649-003 Lisboa, Portugal
| | - Marianna Katz
- Hovione
Farmaciência S.A., Estrada do Paço do Lumiar, Campus do Lumiar, Edifício
R, 1649-038 Lisboa, Portugal
| | - Maria M. M. Santos
- Research
Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Avenida Professor Gama Pinto, 1649-003 Lisboa, Portugal
| | - Carlos A. M. Afonso
- Research
Institute for Medicines (iMed.ULisboa), Faculty of Pharmacy, Universidade de Lisboa, Avenida Professor Gama Pinto, 1649-003 Lisboa, Portugal
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2
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Rahman Chowdhury T, Taufiq T, Ishida K, Ariful Islam M, Kasahara Y, Osawa T, Obika S. Synthesis and biophysical properties of tetravalent PEG-conjugated antisense oligonucleotide. Bioorg Med Chem 2023; 78:117149. [PMID: 36587552 DOI: 10.1016/j.bmc.2022.117149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 12/21/2022] [Accepted: 12/22/2022] [Indexed: 12/27/2022]
Abstract
This study was aimed at developing a novel platform for tetravalent conjugation of 4-arm polyethylene glycol (PEG) with an antisense oligonucleotide (ASO). The ASO technology has several limitations, such as low cellular uptake, poor nuclease stability, and short half-life. PEG-conjugated ASOs may result in an improvement in the pharmacokinetic behavior of the drug. Moreover, PEGylation can reduce enzymatic degradation and renal excretion of the conjugates, thereby, increasing its blood stability and retention time. In this study, we successfully synthesized PEG-ASO conjugate consisting of 4-arm-PEG and four molecules of ASO (4-arm-PEG-tetra ASO). Its hybridization ability with complementary RNA, enzymatic stability, and in vitro gene silencing ability were evaluated. No significant difference in hybridization ability was observed between 4-arm-PEG-tetra ASO and the parent ASO. In addition, gene silencing activity of the 4-arm-PEG-tetra ASO was observed in vitro. However, the in vitro activity of the 4-arm-PEG-tetra ASO was slightly reduced as that of the parent ASO. Moreover, the 4-arm-PEG-tetra ASO showed appreciable stability in cellular extract, suggesting that it hybridizes with mRNA in its intact form, without being cleaved in the cell, and exhibits ASO activity.
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Affiliation(s)
- Taslima Rahman Chowdhury
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
| | - Tahia Taufiq
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
| | - Kenta Ishida
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
| | - Md Ariful Islam
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Yuuya Kasahara
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan
| | - Takashi Osawa
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan
| | - Satoshi Obika
- Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka 565-0871, Japan; National Institutes of Biomedical Innovation, Health and Nutrition (NIBIOHN), 7-6-8 Saito-Asagi, Ibaraki, Osaka 567-0085, Japan; Institute for Open and Transdisciplinary Research Initiatives, Osaka University (OTRI), 1-3 Yamadaoka, Suita, Osaka 565-0871, Japan.
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3
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Godinho BMDC, Knox EG, Hildebrand S, Gilbert JW, Echeverria D, Kennedy Z, Haraszti RA, Ferguson CM, Coles AH, Biscans A, Caiazzi J, Alterman JF, Hassler MR, Khvorova A. PK-modifying anchors significantly alter clearance kinetics, tissue distribution, and efficacy of therapeutics siRNAs. MOLECULAR THERAPY. NUCLEIC ACIDS 2022; 29:116-132. [PMID: 35795486 PMCID: PMC9240963 DOI: 10.1016/j.omtn.2022.06.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 06/05/2022] [Indexed: 11/21/2022]
Abstract
Effective systemic delivery of small interfering RNAs (siRNAs) to tissues other than liver remains a challenge. siRNAs are small (∼15 kDa) and therefore rapidly cleared by the kidneys, resulting in limited blood residence times and tissue exposure. Current strategies to improve the unfavorable pharmacokinetic (PK) properties of siRNAs rely on enhancing binding to serum proteins through extensive phosphorothioate modifications or by conjugation of targeting ligands. Here, we describe an alternative strategy for enhancing blood and tissue PK based on dynamic modulation of the overall size of the siRNA. We engineered a high-affinity universal oligonucleotide anchor conjugated to a high-molecular-weight moiety, which binds to the 3' end of the guide strand of an asymmetric siRNA. Data showed a strong correlation between the size of the PK-modifying anchor and clearance kinetics. Large 40-kDa PK-modifying anchors reduced renal clearance by ∼23-fold and improved tissue exposure area under the curve (AUC) by ∼26-fold, resulting in increased extrahepatic tissue retention (∼3- to 5-fold). Furthermore, PK-modifying oligonucleotide anchors allowed for straightforward and versatile modulation of blood residence times and biodistribution of a panel of chemically distinct ligands. The effects were more pronounced for conjugates with low lipophilicity (e.g., N-Acetylgalactosamine [GalNAc]), where significant improvement in uptake by hepatocytes and dose-dependent silencing in the liver was observed.
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Affiliation(s)
- Bruno M D C Godinho
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Emily G Knox
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Samuel Hildebrand
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - James W Gilbert
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Dimas Echeverria
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Zachary Kennedy
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Reka A Haraszti
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Chantal M Ferguson
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Andrew H Coles
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Annabelle Biscans
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Jillian Caiazzi
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Julia F Alterman
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Matthew R Hassler
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Anastasia Khvorova
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
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4
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Ruseska I, Fresacher K, Petschacher C, Zimmer A. Use of Protamine in Nanopharmaceuticals-A Review. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:1508. [PMID: 34200384 PMCID: PMC8230241 DOI: 10.3390/nano11061508] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/27/2021] [Accepted: 05/27/2021] [Indexed: 12/18/2022]
Abstract
Macromolecular biomolecules are currently dethroning classical small molecule therapeutics because of their improved targeting and delivery properties. Protamine-a small polycationic peptide-represents a promising candidate. In nature, it binds and protects DNA against degradation during spermatogenesis due to electrostatic interactions between the negatively charged DNA-phosphate backbone and the positively charged protamine. Researchers are mimicking this technique to develop innovative nanopharmaceutical drug delivery systems, incorporating protamine as a carrier for biologically active components such as DNA or RNA. The first part of this review highlights ongoing investigations in the field of protamine-associated nanotechnology, discussing the self-assembling manufacturing process and nanoparticle engineering. Immune-modulating properties of protamine are those that lead to the second key part, which is protamine in novel vaccine technologies. Protamine-based RNA delivery systems in vaccines (some belong to the new class of mRNA-vaccines) against infectious disease and their use in cancer treatment are reviewed, and we provide an update on the current state of latest developments with protamine as pharmaceutical excipient for vaccines.
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Affiliation(s)
| | | | | | - Andreas Zimmer
- Department of Pharmaceutical Technology and Biopharmacy, Institute of Pharmaceutical Sciences, Karl-Franzens-University Graz, Universitätsplatz 1, 8010 Graz, Austria; (I.R.); (K.F.); (C.P.)
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5
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Gmeiner WH, Dominijanni A, Haber AO, Ghiraldeli LP, Caudell DL, D'Agostino R, Pasche BC, Smith TL, Deng Z, Kiren S, Mani C, Palle K, Brody JR. Improved Antitumor Activity of the Fluoropyrimidine Polymer CF10 in Preclinical Colorectal Cancer Models through Distinct Mechanistic and Pharmacologic Properties. Mol Cancer Ther 2020; 20:553-563. [PMID: 33361273 DOI: 10.1158/1535-7163.mct-20-0516] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 10/26/2020] [Accepted: 12/16/2020] [Indexed: 12/11/2022]
Abstract
Chemotherapy regimens that include 5-fluorouracil (5-FU) are central to colorectal cancer treatment; however, risk/benefit concerns limit 5-FU's use, necessitating development of improved fluoropyrimidine (FP) drugs. In our study, we evaluated a second-generation nanoscale FP polymer, CF10, for improved antitumor activity. CF10 was more potent than the prototype FP polymer F10 and much more potent than 5-FU in multiple colorectal cancer cell lines including HCT-116, LS174T, SW480, and T84D. CF10 displayed improved stability to exonuclease degradation relative to F10 and reduced susceptibility to thymidine antagonism due to extension of the polymer with arabinosyl cytidine. In colorectal cancer cells, CF10 strongly inhibited thymidylate synthase (TS), induced Top1 cleavage complex formation and caused replication stress, while similar concentrations of 5-FU were ineffective. CF10 was well tolerated in vivo and invoked a reduced inflammatory response relative to 5-FU. Blood chemistry parameters in CF10-treated mice were within normal limits. In vivo, CF10 displayed antitumor activity in several colorectal cancer flank tumor models including HCT-116, HT-29, and CT-26. CF10's antitumor activity was associated with increased plasma levels of FP deoxynucleotide metabolites relative to 5-FU. CF10 significantly reduced tumor growth and improved survival (84.5 days vs. 32 days; P < 0.0001) relative to 5-FU in an orthotopic HCT-116-luc colorectal cancer model that spontaneously metastasized to liver. Improved survival in the orthotopic model correlated with localization of a fluorescent CF10 conjugate to tumor. Together, our preclinical data support an early-phase clinical trial of CF10 for treatment of colorectal cancer.
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Affiliation(s)
- William H Gmeiner
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina.
- Comprehensive Cancer Center Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Anthony Dominijanni
- Wake Forest Institute for Regenerative Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Alex O Haber
- Department of Surgery, Jefferson Pancreas, Biliary and Related Cancer Center, Thomas Jefferson University, Philadelphia, Pennsylvania
| | - Lais P Ghiraldeli
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - David L Caudell
- Department of Pathology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Ralph D'Agostino
- Department of Public Health Sciences, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Boris C Pasche
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina
- Comprehensive Cancer Center Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Thomas L Smith
- Department of Orthopedic Surgery, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Zhiyong Deng
- Department of Cancer Biology, Wake Forest School of Medicine, Winston-Salem, North Carolina
| | - Sezgin Kiren
- Department of Chemistry, Winston-Salem State University, Winston-Salem, North Carolina
| | - Chinnadurai Mani
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Centre, Lubbock, Texas
| | - Komaraiah Palle
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Centre, Lubbock, Texas
| | - Jonathan R Brody
- Brenden Colson Center for Pancreatic Care, Departments of Surgery and Cell, Developmental & Cancer Biology, Knight Cancer Institute, Oregon Health and Science University, Portland, Oregon
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6
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Transport Oligonucleotides-A Novel System for Intracellular Delivery of Antisense Therapeutics. Molecules 2020; 25:molecules25163663. [PMID: 32796768 PMCID: PMC7464317 DOI: 10.3390/molecules25163663] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 08/10/2020] [Accepted: 08/11/2020] [Indexed: 12/12/2022] Open
Abstract
Biological activity of antisense oligonucleotides (asON), especially those with a neutral backbone, is often attenuated by poor cellular accumulation. In the present proof-of-concept study, we propose a novel delivery system for asONs which implies the delivery of modified antisense oligonucleotides by so-called transport oligonucleotides (tON), which are oligodeoxyribonucleotides complementary to asON conjugated with hydrophobic dodecyl moieties. Two types of tONs, bearing at the 5′-end up to three dodecyl residues attached through non-nucleotide inserts (TD series) or anchored directly to internucleotidic phosphate (TP series), were synthesized. tONs with three dodecyl residues efficiently delivered asON to cells without any signs of cytotoxicity and provided a transfection efficacy comparable to that achieved using Lipofectamine 2000. We found that, in the case of tON with three dodecyl residues, some tON/asON duplexes were excreted from the cells within extracellular vesicles at late stages of transfection. We confirmed the high efficacy of the novel and demonstrated that MDR1 mRNA targeted asON delivered by tON with three dodecyl residues significantly reduced the level of P-glycoprotein and increased the sensitivity of KB-8-5 human carcinoma cells to vinblastine. The obtained results demonstrate the efficacy of lipophilic oligonucleotide carriers and shows they are potentially capable of intracellular delivery of any kind of antisense oligonucleotides.
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7
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Oligo-guanidyl targeted bioconjugates forming rod shaped polyplexes as a new nanoplatform for oligonucleotide delivery. J Control Release 2019; 310:58-73. [PMID: 31400381 DOI: 10.1016/j.jconrel.2019.08.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Revised: 08/04/2019] [Accepted: 08/06/2019] [Indexed: 12/15/2022]
Abstract
Novel bioconjugates (Agm6-M-PEG-FA) for active oligonucleotide (ON) delivery have been developed by conjugating a cationic oligo-guanidyl star-like shaped "head" (Agm6-M) to a polymeric "tail" (PEG) terminating with folic acid (FA) as targeting agent or methoxy group (Agm6-M-PEG-FA and Agm6-M-PEG-OCH3, respectively). Gel electrophoresis showed that the bioconjugates completely associated with ONs at 3 nitrogen/phosphate (N/P) ratio. Studies performed with folate receptor (FR)-overexpressing HeLa cells, showed that optimal cell up-take was obtained with the 75:25 w/w Agm6-M-PEG-OCH3:Agm6-M-PEG-FA mixture. Dynamic light scattering and transmission electron microscopy showed that the polyplexes had size <80 nm with narrow polydispersity and rod-shaped morphology. The polyplexes were stable for several hours in plasma while ON was released in the presence of heparin concentration 16-times higher than the physiological one. The polyplexes displayed negligible cytotoxicity, hemolysis and low pro-inflammatory TNF-α release. Studies performed with FR-overexpressing HeLa and MDA-MB-231 cells using siRac1 revealed that the folated polyplexes caused significantly higher gene silencing (86.1 ± 9.6%) and inhibition of cell migration (40%) than the non-folated polyplexes obtained with Agm6-M-PEG-OCH3 only. Although cytofluorimetric analyses showed similar cell uptake for both folated and non-folated polyplexes, confocal, TEM and competition studies showed that the folated polyplexes were taken-up by lysosome escaping caveolin-mediated pathway with final polyplex localization within cytosol, while non-folated polyplexes were preferentially taken-up via clathrin-mediated pathway to localize in the lysosomes. Finally, preliminary in vivo studies carried out in mice revealed that the folated polyplexes dispose in the tumor mass.
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8
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Covalent Fluorophore Labeling of Oligonucleotides and Generation of Other Oligonucleotide Bioconjugates. Methods Mol Biol 2019; 1943:61-72. [PMID: 30838609 DOI: 10.1007/978-1-4939-9092-4_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Oligonucleotide conjugates have already reached considerable importance in life science research and oligonucleotide drug development. Since the preparation of oligonucleotide conjugates depends critically on the chemical nature of the used ligand and linker, there is no general and universal procedure. Here, we present a detailed, quick, and facile protocol for attaching fluorescent dyes or cross-linkers of variable chemical stability to oligonucleotides at 3'- or 5'-aminoalkyl handles. Purification and removal of educts and side-products and structural verification by gel electrophoresis and mass spectrometry are presented. Aspects for adapting this protocol for other reaction sites at the oligonucleotide are discussed. We highlight important issues for generating oligonucleotide conjugates with other molecules, including peptide, proteins, and small molecules for receptor-targeting applications. The methodology is suitable for oligonucleotides with various modifications, including stabilized antisense, siRNAs, and miRNAs.
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9
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Lu X, Zhang K. PEGylation of therapeutic oligonucletides: From linear to highly branched PEG architectures. NANO RESEARCH 2018; 11:5519-5534. [PMID: 30740197 PMCID: PMC6366847 DOI: 10.1007/s12274-018-2131-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 06/08/2018] [Accepted: 06/18/2018] [Indexed: 05/12/2023]
Abstract
PEGylation, the attachment of poly(ethylene glycol) (PEG), has been adopted to improve the pharmacokinetic properties of oligonucleotide therapeutics for nearly 30 years. Prior efforts mainly focused on the investigation of linear or slightly branched PEG having different molecular weights, terminal functional groups, and possible oligonucleotide sites for functionalization. Recent studies on highly branched PEG (including brush, star, and micellar structures) indicate superior properties in several areas including cellular uptake, gene regulation efficacy, reduction of side effects, and biodistribution. This review focuses on comparing the effects of PEG architecture on the physiochemical and biological properties of the PEGylated oligonucleotide.
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Affiliation(s)
- Xueguang Lu
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, USA
| | - Ke Zhang
- Department of Chemistry and Chemical Biology, Northeastern University, Boston, Massachusetts 02115, USA
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10
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Isakari Y, Kishi Y, Yoshimoto N, Yamamoto S, Podgornik A. Reaction-Mediated Desorption of Macromolecules: Novel Phenomenon Enabling Simultaneous Reaction and Separation. Biotechnol J 2018; 13:e1700738. [PMID: 29393589 DOI: 10.1002/biot.201700738] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/22/2018] [Indexed: 12/11/2022]
Abstract
Combining chemical reaction with separation offers several advantages. In this work possibility to induce spontaneous desorption of adsorbed macromolecules, once being PEGylated, through adjustment of the reagent composition is investigated. Bovine serum albumin (BSA) and activated oligonucleotide, 9T, are used as the test molecules and 20 kDa linear activated PEG is used for their PEGylation. BSA solid-phase PEGylation is performed on Q Sepharose HP. Distribution coefficient of BSA and PEG-BSA as a function of NaCl is determined using linear gradient elution (LGE) experiments and Yamamoto model. According to the distribution coefficient the selectivity between BSA and PEG - BSA of around 15 is adjusted by using NaCl. Spontaneous desorption of PEG - BSA is detected with no presence of BSA. However, due to a rather low selectivity, also desorption of BSA occurred at high elution volume. A similar procedure is applied for activated 9T oligonucleotide, this time using monolithic CIM QA disk monolithic column for adsorption. Selectivity of over 2000 is obtained by proper adjustment of PEG reagent composition. High selectivity enables spontaneous desorption of PEG-9T without any desorption of activated 9T. Both experiments demonstrates that reaction-mediated desorption of macromolecules is possible when the reaction conditions are properly tuned.
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Affiliation(s)
- Yu Isakari
- Bio-Process Engineering Laboratory, School of Engineering and Graduate School of Medicine, Yamaguchi University, Ube, Japan
| | - Yuhi Kishi
- Bio-Process Engineering Laboratory, School of Engineering and Graduate School of Medicine, Yamaguchi University, Ube, Japan
| | - Noriko Yoshimoto
- Bio-Process Engineering Laboratory, School of Engineering and Graduate School of Medicine, Yamaguchi University, Ube, Japan.,Biomedical Engineering Center (YUBEC), Yamaguchi University, Ube, Japan
| | - Shuichi Yamamoto
- Bio-Process Engineering Laboratory, School of Engineering and Graduate School of Medicine, Yamaguchi University, Ube, Japan.,Biomedical Engineering Center (YUBEC), Yamaguchi University, Ube, Japan
| | - Aleš Podgornik
- Faculty of Chemistry and Chemical Technology, University of Ljubljana, Ljubljana, Slovenia.,Center of Excellence COBIK, Ajdovščina, Slovenia
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11
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González Torres M, Cerna Cortez J, Balam Muñoz Soto R, Ríos Perez A, Pfeiffer H, Leyva Gómez G, Zúñiga Ramos J, Rivera AL. Synthesis of gamma radiation-induced PEGylated cisplatin for cancer treatment. RSC Adv 2018; 8:34718-34725. [PMID: 35548615 PMCID: PMC9086999 DOI: 10.1039/c8ra06296j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2018] [Accepted: 09/29/2018] [Indexed: 01/06/2023] Open
Abstract
The synthesis of gamma radiation-induced PEGylated cisplatin paves the way to a new alternative PEGylation of small drugs.
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Affiliation(s)
- Maykel González Torres
- Escuela de Ingeniería y Ciencias
- Instituto Tecnológico y de Estudios Superiores de Monterrey
- Mexico
- Laboratorio de Biotecnología
- Instituto Nacional de Rehabilitación “Luís Guillermo Ibarra Ibarra”
| | - Jorge Cerna Cortez
- Benemérita Universidad Autónoma de Puebla
- Facultad de Química
- Puebla
- Mexico
| | - Rodrigo Balam Muñoz Soto
- Escuela de Ingeniería y Ciencias
- Instituto Tecnológico y de Estudios Superiores de Monterrey
- Mexico
| | - Alfonso Ríos Perez
- Escuela de Ingeniería y Ciencias
- Instituto Tecnológico y de Estudios Superiores de Monterrey
- Mexico
| | - Heriberto Pfeiffer
- Instituto de Investigaciones en Materiales
- Universidad Nacional Autónoma de México
- Ciudad de México
- Mexico
| | - Gerardo Leyva Gómez
- Facultad de Química
- Universidad Nacional Autónoma de México
- Ciudad de México 04510
- Mexico
| | - Joaquín Zúñiga Ramos
- Instituto Nacional de Enfermedades Respiratorias Ismael Cosío Villegas
- Ciudad de México
- Mexico
| | - Ana Leonor Rivera
- Instituto de Ciencias Nucleares
- Universidad Nacional Autónoma de México
- Ciudad de México 04510
- Mexico
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12
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Malhotra M, Gooding M, Evans JC, O'Driscoll D, Darcy R, O'Driscoll CM. Cyclodextrin-siRNA conjugates as versatile gene silencing agents. Eur J Pharm Sci 2017; 114:30-37. [PMID: 29191522 DOI: 10.1016/j.ejps.2017.11.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Revised: 11/26/2017] [Accepted: 11/26/2017] [Indexed: 10/18/2022]
Abstract
Functional siRNAs (luciferase and PLK1) have been conjugated to β-cyclodextrin and the ability of the conjugates to retain gene knockdown activity has been assessed by delivery to cancer cell lines using various formulations. Initially two formulations used complexation with polycations, namely Lipofectamine 2000 and an amphiphilic polycationic cyclodextrin. Gene knockdown results for human glioblastoma cells (U87) and prostate cancer cells (PC3, DU145) showed that conjugation to the cyclodextrin did not reduce gene silencing by the RNA. A third mode of delivery involved formation of targeted nanoparticles in which the conjugate was first complexed with adamantyl-PEG-ligands (targeting ligand RVG peptide or dianisamide) by adamantyl inclusion in the cyclodextrin cavities of the conjugates, followed by charge neutralisation with the cationic polymer chitosan. Enhanced knockdown was achieved by these ligand-targeted formulations. In summary, while this study illustrated the gene silencing efficacy of a simple cyclodextrin-siRNA conjugate it is envisaged that future studies will explore the use of conjugates with a modified cyclodextrin which would be self-delivering. Detailed data such as stability, lysosomal escape etc. will then be reported for each conjugate, since this will be appropriate for conjugates which are intended to exploit, rather than merely demonstrate, the concept. The present paper was intended to demonstrate the viability and generality of this novel concept.
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Affiliation(s)
- Meenakshi Malhotra
- Pharmacodelivery group, School of Pharmacy, University College Cork, Cork, Ireland; Department of Radiology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Matt Gooding
- Pharmacodelivery group, School of Pharmacy, University College Cork, Cork, Ireland
| | - James C Evans
- Pharmacodelivery group, School of Pharmacy, University College Cork, Cork, Ireland; Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, Ontario M5S 3M2, Canada
| | - Daniel O'Driscoll
- Alimentary Pharmabiotic Centre, Microbiome Institute, University College Cork, Ireland
| | - Raphael Darcy
- Pharmacodelivery group, School of Pharmacy, University College Cork, Cork, Ireland
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13
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Baumann V, Lorenzer C, Thell M, Winkler AM, Winkler J. RNAi-Mediated Knockdown of Protein Expression. Methods Mol Biol 2017; 1654:351-360. [PMID: 28986804 DOI: 10.1007/978-1-4939-7231-9_26] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
RNA interference is an essential method for studying genomic functions of single genes by loss-of-function experiments. Short interfering siRNAs are efficiently transfected into cultured cells to enable RISC-mediated mRNA cleavage and inhibition of translation in a sequence-specific manner. RNAi enables knockdown of single genes and screening for specific cellular processes or outcomes. In this chapter, we describe a detailed universal protocol for lipoplex-mediated siRNA transfection for cell cultures and cell lysis for subsequent RNA or protein analysis. The experimental procedure is described for verification of knockdown and includes cell lysis for mRNA or protein quantification. Important aspects for specific gene silencing and potential pitfalls are discussed.
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Affiliation(s)
- Volker Baumann
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstraße 14, 1090, Vienna, Austria
| | - Cornelia Lorenzer
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstraße 14, 1090, Vienna, Austria
| | - Michael Thell
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstraße 14, 1090, Vienna, Austria
| | - Anna-Maria Winkler
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstraße 14, 1090, Vienna, Austria
| | - Johannes Winkler
- Department of Pharmaceutical Chemistry, University of Vienna, Althanstraße 14, 1090, Vienna, Austria.
- Department of Cardiology, Medical University of Vienna, Währinger Gürtel 18-20, 1090, Vienna, Austria.
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14
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Gooding M, Malhotra M, Evans JC, Darcy R, O'Driscoll CM. Oligonucleotide conjugates - Candidates for gene silencing therapeutics. Eur J Pharm Biopharm 2016; 107:321-40. [PMID: 27521696 DOI: 10.1016/j.ejpb.2016.07.024] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Revised: 07/24/2016] [Accepted: 07/25/2016] [Indexed: 11/18/2022]
Abstract
The potential therapeutic and diagnostic applications of oligonucleotides (ONs) have attracted great attention in recent years. The capability of ONs to selectively inhibit target genes through antisense and RNA interference mechanisms, without causing un-intended sideeffects has led them to be investigated for various biomedical applications, especially for the treatment of viral diseases and cancer. In recent years, many researchers have focused on enhancing the stability and target specificity of ONs by encapsulating/complexing them with polymers or lipid chains to formulate nanoparticles/nanocomplexes/micelles. Also, chemical modification of nucleic acids has emerged as an alternative to impart stability to ONs against nucleases and other degrading enzymes and proteins found in blood. In addition to chemically modifying the nucleic acids directly, another strategy that has emerged, involves conjugating polymers/peptide/aptamers/antibodies/proteins, preferably to the sense strand (3'end) of siRNAs. Conjugation to the siRNA not only enhances the stability and targeting specificity of the siRNA, but also allows for the development of self-administering siRNA formulations, with a much smaller size than what is usually observed for nanoparticle (∼200nm). This review concentrates mainly on approaches and studies involving ON-conjugates for biomedical applications.
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Affiliation(s)
- Matt Gooding
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
| | - Meenakshi Malhotra
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
| | - James C Evans
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
| | - Raphael Darcy
- Pharmacodelivery Group, School of Pharmacy, University College Cork, Cork, Ireland
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15
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Fragment-based solid-phase assembly of oligonucleotide conjugates with peptide and polyethylene glycol ligands. Eur J Med Chem 2016; 121:132-142. [PMID: 27236069 DOI: 10.1016/j.ejmech.2016.05.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2015] [Revised: 04/25/2016] [Accepted: 05/01/2016] [Indexed: 12/26/2022]
Abstract
Ligand conjugation to oligonucleotides is an attractive strategy for enhancing the therapeutic potential of antisense and siRNA agents by inferring properties such as improved cellular uptake or better pharmacokinetic properties. Disulfide linkages enable dissociation of ligands and oligonucleotides in reducing environments found in endosomal compartments after cellular uptake. Solution-phase fragment coupling procedures for producing oligonucleotide conjugates are often tedious, produce moderate yields and reaction byproducts are frequently difficult to remove. We have developed an improved method for solid-phase coupling of ligands to oligonucleotides via disulfides directly after solid-phase synthesis. A 2'-thiol introduced using a modified nucleotide building block was orthogonally deprotected on the controlled pore glass solid support with N-butylphosphine. Oligolysine peptides and a short monodisperse ethylene glycol chain were successfully coupled to the deprotected thiol. Cleavage from the resin and full removal of oligonucleotide protection groups were achieved using methanolic ammonia. After standard desalting, and without further purification, homogenous conjugates were obtained as demonstrated by HPLC, gel electrophoresis, and mass spectrometry. The attachment of both amphiphilic and cationic ligands proves the versatility of the conjugation procedure. An antisense oligonucleotide conjugate with hexalysine showed pronounced gene silencing in a cell culture tumor model in the absence of a transfection reagent and the corresponding ethylene glycol conjugate resulted in down regulation of the target gene to nearly 50% after naked application.
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16
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Uematsu R, Inagaki M, Asai M, Sugai H, Maeda Y, Nagami A, Sato H, Sakamoto S, Araki Y, Nishijima M, Inoue Y, Wada T. Module Strategy for Peptide Ribonucleic Acid (PRNA)–DNA and PRNA–Peptide Nucleic Acid (PNA)–DNA Chimeras: Synthesis and Interaction of Chimeras with DNA and RNA. CHEM LETT 2016. [DOI: 10.1246/cl.151157] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Ryohei Uematsu
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University
| | - Masahito Inagaki
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University
| | - Mitsuo Asai
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University
| | - Hiroka Sugai
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University
| | | | - Akira Nagami
- Department of Applied Chemistry, Osaka University
| | | | - Seiji Sakamoto
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University
| | - Yasuyuki Araki
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University
| | | | | | - Takehiko Wada
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University
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17
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Hong S, Sun N, Liu M, Wang J, Pei R. Building a chimera of aptamer–antisense oligonucleotide for silencing galectin-1 gene. RSC Adv 2016. [DOI: 10.1039/c6ra21250f] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Galectin-1 is closely related with immune systems, and its overexpression may cause tumor metastasis.
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Affiliation(s)
- Shanni Hong
- School of Nano Technology and Nano Bionics
- University of Science and Technology of China
- Hefei 230026
- China
- Suzhou Institute of Nano-Tech and Nano-Bionics
| | - Na Sun
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou 215123
- China
| | - Min Liu
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou 215123
- China
| | - Jine Wang
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou 215123
- China
| | - Renjun Pei
- Suzhou Institute of Nano-Tech and Nano-Bionics
- Chinese Academy of Sciences
- Suzhou 215123
- China
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18
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Herzberger J, Niederer K, Pohlit H, Seiwert J, Worm M, Wurm FR, Frey H. Polymerization of Ethylene Oxide, Propylene Oxide, and Other Alkylene Oxides: Synthesis, Novel Polymer Architectures, and Bioconjugation. Chem Rev 2015; 116:2170-243. [PMID: 26713458 DOI: 10.1021/acs.chemrev.5b00441] [Citation(s) in RCA: 451] [Impact Index Per Article: 50.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The review summarizes current trends and developments in the polymerization of alkylene oxides in the last two decades since 1995, with a particular focus on the most important epoxide monomers ethylene oxide (EO), propylene oxide (PO), and butylene oxide (BO). Classical synthetic pathways, i.e., anionic polymerization, coordination polymerization, and cationic polymerization of epoxides (oxiranes), are briefly reviewed. The main focus of the review lies on more recent and in some cases metal-free methods for epoxide polymerization, i.e., the activated monomer strategy, the use of organocatalysts, such as N-heterocyclic carbenes (NHCs) and N-heterocyclic olefins (NHOs) as well as phosphazene bases. In addition, the commercially relevant double-metal cyanide (DMC) catalyst systems are discussed. Besides the synthetic progress, new types of multifunctional linear PEG (mf-PEG) and PPO structures accessible by copolymerization of EO or PO with functional epoxide comonomers are presented as well as complex branched, hyperbranched, and dendrimer like polyethers. Amphiphilic block copolymers based on PEO and PPO (Poloxamers and Pluronics) and advances in the area of PEGylation as the most important bioconjugation strategy are also summarized. With the ever growing toolbox for epoxide polymerization, a "polyether universe" may be envisaged that in its structural diversity parallels the immense variety of structural options available for polymers based on vinyl monomers with a purely carbon-based backbone.
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Affiliation(s)
- Jana Herzberger
- Institute of Organic Chemistry, Johannes Gutenberg-University Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.,Graduate School Materials Science in Mainz , Staudingerweg 9, D-55128 Mainz, Germany
| | - Kerstin Niederer
- Institute of Organic Chemistry, Johannes Gutenberg-University Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany
| | - Hannah Pohlit
- Institute of Organic Chemistry, Johannes Gutenberg-University Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.,Graduate School Materials Science in Mainz , Staudingerweg 9, D-55128 Mainz, Germany.,Max Planck Graduate Center , Staudingerweg 6, D-55128 Mainz, Germany.,Department of Dermatology, University Medical Center , Langenbeckstraße 1, D-55131 Mainz, Germany
| | - Jan Seiwert
- Institute of Organic Chemistry, Johannes Gutenberg-University Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany
| | - Matthias Worm
- Institute of Organic Chemistry, Johannes Gutenberg-University Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.,Max Planck Graduate Center , Staudingerweg 6, D-55128 Mainz, Germany
| | - Frederik R Wurm
- Max Planck Graduate Center , Staudingerweg 6, D-55128 Mainz, Germany.,Max Planck Institute for Polymer Research , Ackermannweg 10, D-55128 Mainz, Germany
| | - Holger Frey
- Institute of Organic Chemistry, Johannes Gutenberg-University Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.,Graduate School Materials Science in Mainz , Staudingerweg 9, D-55128 Mainz, Germany
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Therapeutic oligonucleotides with polyethylene glycol modifications. Future Med Chem 2015; 7:1721-31. [PMID: 26465713 DOI: 10.4155/fmc.15.94] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
In the field of oligonucleotide drugs, the attachment of PEG is a well-established strategy to prevent enzymatic degradation and avoid renal elimination. Pegaptanib and other oligonucleotides in clinical development utilize the attachment of linear or branched high molecular weight PEG chains for increase of accumulation and duration of the effect after local or systemic application. The length of PEG chains is decisive for the pharmacokinetic and pharmacodynamic effects. Longer chains increase circulation times, but generally decrease gene-silencing efficiencies for antisense and siRNA agents and binding affinities for aptamers. Shorter chains are less efficient in preventing renal filtration, but have also less impact on the gene-silencing machinery and binding kinetics.
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20
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Lorenzer C, Dirin M, Winkler AM, Baumann V, Winkler J. Going beyond the liver: progress and challenges of targeted delivery of siRNA therapeutics. J Control Release 2015; 203:1-15. [PMID: 25660205 DOI: 10.1016/j.jconrel.2015.02.003] [Citation(s) in RCA: 205] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 01/29/2015] [Accepted: 02/02/2015] [Indexed: 12/25/2022]
Abstract
Therapeutic gene silencing promises significant progress in pharmacotherapy, including considerable expansion of the druggable target space and the possibility for treating orphan diseases. Technological hurdles have complicated the efficient use of therapeutic oligonucleotides, and siRNA agents suffer particularly from insufficient pharmacokinetic properties and poor cellular uptake. Intense development and evolution of delivery systems have resulted in efficient uptake predominantly in liver tissue, in which practically all nanoparticulate and liposomal delivery systems show the highest accumulation. The most efficacious strategies include liposomes and bioconjugations with N-acetylgalactosamine. Both are in early clinical evaluation stages for treatment of liver-associated diseases. Approaches for achieving knockdown in other tissues and tumors have been proven to be more complicated. Selective targeting to tumors may be enabled through careful modulation of physical properties, such as particle size, or by taking advantage of specific targeting ligands. Significant barriers stand between sufficient accumulation in other organs, including endothelial barriers, cellular membranes, and the endosome. The brain, which is shielded by the blood-brain barrier, is of particular interest to facilitate efficient oligonucleotide therapy of neurological diseases. Transcytosis of the blood-brain barrier through receptor-specific docking is investigated to increase accumulation in the central nervous system. In this review, the current clinical status of siRNA therapeutics is summarized, as well as innovative and promising preclinical concepts employing tissue- and tumor-targeted ligands. The requirements and the respective advantages and drawbacks of bioconjugates and ligand-decorated lipid or polymeric particles are discussed.
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Affiliation(s)
- Cornelia Lorenzer
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstraße 14, 1090 Vienna, Austria
| | - Mehrdad Dirin
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstraße 14, 1090 Vienna, Austria
| | - Anna-Maria Winkler
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstraße 14, 1090 Vienna, Austria
| | - Volker Baumann
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstraße 14, 1090 Vienna, Austria
| | - Johannes Winkler
- University of Vienna, Department of Pharmaceutical Chemistry, Althanstraße 14, 1090 Vienna, Austria.
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