1
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Subramanian M, McIninch J, Zlatev I, Schlegel MK, Kaittanis C, Nguyen T, Agarwal S, Racie T, Alvarado MA, Wassarman K, Collins TS, Chickering T, Brown CR, Schmidt K, Castoreno AB, Shulga-Morskaya S, Stamenova E, Buckowing K, Berman D, Barry JD, Bisbe A, Maier MA, Fitzgerald K, Jadhav V. RNAi-mediated rheostat for dynamic control of AAV-delivered transgenes. Nat Commun 2023; 14:1970. [PMID: 37031257 PMCID: PMC10082758 DOI: 10.1038/s41467-023-37774-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Accepted: 03/29/2023] [Indexed: 04/10/2023] Open
Abstract
Adeno-associated virus (AAV)-based gene therapy could be facilitated by the development of molecular switches to control the magnitude and timing of expression of therapeutic transgenes. RNA interference (RNAi)-based approaches hold unique potential as a clinically proven modality to pharmacologically regulate AAV gene dosage in a sequence-specific manner. We present a generalizable RNAi-based rheostat wherein hepatocyte-directed AAV transgene expression is silenced using the clinically validated modality of chemically modified small interfering RNA (siRNA) conjugates or vectorized co-expression of short hairpin RNA (shRNA). For transgene induction, we employ REVERSIR technology, a synthetic high-affinity oligonucleotide complementary to the siRNA or shRNA guide strand to reverse RNAi activity and rapidly recover transgene expression. For potential clinical development, we report potent and specific siRNA sequences that may allow selective regulation of transgenes while minimizing unintended off-target effects. Our results establish a conceptual framework for RNAi-based regulatory switches with potential for infrequent dosing in clinical settings to dynamically modulate expression of virally-delivered gene therapies.
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Affiliation(s)
| | | | - Ivan Zlatev
- Alnylam Pharmaceuticals, Cambridge, MA, 02142, USA
| | | | | | - Tuyen Nguyen
- Alnylam Pharmaceuticals, Cambridge, MA, 02142, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - Anna Bisbe
- Alnylam Pharmaceuticals, Cambridge, MA, 02142, USA
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2
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Jones JD, Grassmyer KT, Kennedy RT, Koutmou KS, Maloney TD. Nuclease P1 Digestion for Bottom-Up RNA Sequencing of Modified siRNA Therapeutics. Anal Chem 2023; 95:4404-4411. [PMID: 36812429 DOI: 10.1021/acs.analchem.2c04902] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023]
Abstract
siRNA therapeutics provide a selective and powerful approach to reduce the expression of disease-causing genes. For regulatory approval, these modalities require sequence confirmation which is typically achieved by intact tandem mass spectrometry sequencing. However, this process produces highly complex spectra which are difficult to interpret and typically results in less than full sequence coverage. We sought to develop a bottom-up siRNA sequencing platform to ease sequencing data analysis and provide full sequence coverage. Analogous to bottom-up proteomics, this process requires chemical or enzymatic digestion to reduce the oligonucleotide length down to analyzable lengths, but siRNAs commonly contain modifications that inhibit the degradation process. We tested six digestion schemes for their feasibility to digest the 2' modified siRNAs and identified that nuclease P1 provides an effective digestion workflow. Using a partial digestion, nuclease P1 provides high 5' and 3' end sequence coverage with multiple overlapping digestion products. Additionally, this enzyme provides high-quality and highly reproducible RNA sequencing no matter the RNA phosphorothioate content, 2'-fluorination status, sequence, or length. Overall, we developed a robust enzymatic digestion scheme for bottom-up siRNA sequencing using nuclease P1, which can be implemented into existing sequence confirmation workflows.
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Affiliation(s)
- Joshua D Jones
- Department of Chemistry, University of Michigan, 930 N University, Ann Arbor, Michigan 48109, United States.,Synthetic Molecule Design and Development, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, United States
| | - Kathleen T Grassmyer
- Synthetic Molecule Design and Development, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, United States
| | - Robert T Kennedy
- Department of Chemistry, University of Michigan, 930 N University, Ann Arbor, Michigan 48109, United States
| | - Kristin S Koutmou
- Department of Chemistry, University of Michigan, 930 N University, Ann Arbor, Michigan 48109, United States
| | - Todd D Maloney
- Synthetic Molecule Design and Development, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, Indiana 46285, United States
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3
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Richter M, Viel JA, Kotikam V, Gajula PK, Coyle L, Pal C, Rozners E. Amide Modifications in the Seed Region of the Guide Strand Improve the On-Target Specificity of Short Interfering RNA. ACS Chem Biol 2023; 18:7-11. [PMID: 36580486 PMCID: PMC9894624 DOI: 10.1021/acschembio.2c00769] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
RNA interference (RNAi) is a well-established research tool and is also maturing as a novel therapeutic approach. For the latter, microRNA-like off-target activity of short interfering RNAs (siRNAs) remains as one of the main problems limiting RNAi drug development. In this communication, we report that replacement of a single internucleoside phosphodiester in the seed region (nucleotides 2 to 7) of the guide strand with an amide linkage suppressed the undesired microRNA-like off-target activity by at least an order of magnitude. For the specific siRNA targeting the PIK3CB gene, an amide modification between the third and fourth nucleotides of the guide strand showed the strongest enhancement of specificity (completely eliminated off-target silencing) while maintaining high on-target activity. These results are important because off-target activity is one of the main remaining roadblocks for RNA based drug development.
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Affiliation(s)
- Michael Richter
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Julien A. Viel
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Venubabu Kotikam
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Praveen Kumar Gajula
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Lamorna Coyle
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Chandan Pal
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
| | - Eriks Rozners
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, New York 13902, United States
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4
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Hofmeister A, Jahn-Hofmann K, Brunner B, Helms M, Metz-Weidmann C, Krack A, Kurz M, Heubel C, Scheidler S. Small Interfering RNAs Containing Dioxane- and Morpholino-Derived Nucleotide Analogues Show Improved Off-Target Profiles and Chirality-Dependent In Vivo Knock-Down. J Med Chem 2022; 65:13736-13752. [PMID: 36223135 DOI: 10.1021/acs.jmedchem.2c00873] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To expand the applicability of recently developed dioxane- and morpholino-based nucleotide analogues, their seed region destabilizing properties in small interfering RNAs (siRNAs) were investigated in order to improve potential off-target profiles. For this purpose, the corresponding adenosine analogues were synthesized in two diastereomeric series as building blocks for the automated oligonucleotide synthesis. The obtained nucleotide precursors were integrated at position 7 of an siRNA antisense strand, targeting transthyretin messenger RNA. Evaluation of the melting temperatures revealed significant differences in the obtained duplex stabilities between the two diastereomeric series, while the influence of the central scaffold was small. All siRNAs containing these novel nucleotide structures showed improved off-target profiles in vitro compared to their parent sequence with the common 2'-OMe-modified adenosine at the same position. In contrast, in vivo potencies were highly dependent on the chirality within the six-membered nucleotide scaffolds and showed high mRNA downregulations for the (2R,6R)-configured diastereomers.
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Affiliation(s)
- Armin Hofmeister
- Sanofi R&D, Industrial Park Hoechst, Frankfurt am Main 65926, Germany
| | | | - Bodo Brunner
- Sanofi R&D, Industrial Park Hoechst, Frankfurt am Main 65926, Germany
| | - Mike Helms
- Sanofi R&D, Industrial Park Hoechst, Frankfurt am Main 65926, Germany
| | | | - Arne Krack
- Sanofi R&D, Industrial Park Hoechst, Frankfurt am Main 65926, Germany
| | - Michael Kurz
- Sanofi R&D, Industrial Park Hoechst, Frankfurt am Main 65926, Germany
| | - Christoph Heubel
- Sanofi R&D, Industrial Park Hoechst, Frankfurt am Main 65926, Germany
| | - Sabine Scheidler
- Sanofi R&D, Industrial Park Hoechst, Frankfurt am Main 65926, Germany
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5
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Cheminformatics Modeling of Gene Silencing for Both Natural and Chemically Modified siRNAs. Molecules 2022; 27:molecules27196412. [PMID: 36234948 PMCID: PMC9570765 DOI: 10.3390/molecules27196412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 09/23/2022] [Accepted: 09/25/2022] [Indexed: 11/17/2022] Open
Abstract
In designing effective siRNAs for a specific mRNA target, it is critically important to have predictive models for the potency of siRNAs. None of the published methods characterized the chemical structures of individual nucleotides constituting a siRNA molecule; therefore, they cannot predict the potency of gene silencing by chemically modified siRNAs (cm-siRNA). We propose a new approach that can predict the potency of gene silencing by cm-siRNAs, which characterizes each nucleotide (NT) using 12 BCUT cheminformatics descriptors describing its charge distribution, hydrophobic and polar properties. Thus, a 21-NT siRNA molecule is described by 252 descriptors resulting from concatenating all the BCUT values of its composing nucleotides. Partial Least Square is employed to develop statistical models. The Huesken data (2431 natural siRNA molecules) were used to perform model building and evaluation for natural siRNAs. Our results were comparable with or superior to those from Huesken’s algorithm. The Bramsen dataset (48 cm-siRNAs) was used to build and test the models for cm-siRNAs. The predictive r2 of the resulting models reached 0.65 (or Pearson r values of 0.82). Thus, this new method can be used to successfully model gene silencing potency by both natural and chemically modified siRNA molecules.
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Knockdown of 15-bp Deletion-Type v-raf Murine Sarcoma Viral Oncogene Homolog B1 mRNA in Pancreatic Ductal Adenocarcinoma Cells Repressed Cell Growth In Vitro and Tumor Volume In Vivo. Cancers (Basel) 2022; 14:cancers14133162. [PMID: 35804932 PMCID: PMC9264874 DOI: 10.3390/cancers14133162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Revised: 06/22/2022] [Accepted: 06/24/2022] [Indexed: 11/17/2022] Open
Abstract
Simple Summary The v-raf murine sarcoma viral oncogene homolog B1 (BRAF) gene containing a 15-base pair (bp) deletion at L485-P490 is the cause of several cancers. We generated siRNA to specifically knock down BRAF mRNA containing the 15-bp deletion. This siRNA suppressed the expression of BRAF, harboring the deletion without affecting wild-type BRAF expression in BxPC-3 pancreatic ductal adenocarcinoma cells in vitro and in vivo. Cell growth and phosphorylation of downstream extracellular-signal-regulated kinase proteins were also repressed. An off-target effect is the most common side effect of siRNA therapy. In this study, we reveal that siRNA with a 2′-O-methyl chemical modification in the seed region of the siRNA guide strand reduced seed-dependent off-target effects. Abstract Pancreatic ductal adenocarcinoma (PDAC) is predicted to become the second-most common cause of death within the next 10 years. Due to the limited efficacy of available therapies, the survival rate of PDAC patients is very low. Oncogenic BRAF mutations are one of the major causes of PDAC, specifically the missense V600E and L485–P490 15-bp deletion mutations. Drugs targeting the V600E mutation have already been approved by the United States Food and Drug Administration. However, a drug targeting the deletion mutation at L485–P490 of the BRAF gene has not been developed to date. The BxPC-3 cell line is a PDAC-derived cell line harboring wild-type KRAS and L485–P490 deleted BRAF genes. These cells are heterozygous for BRAF, harboring both wild-type BRAF and BRAF with the 15-bp deletion. In this study, siRNA was designed for the targeted knockdown of 15-bp deletion-type BRAF mRNA. This siRNA repressed the phosphorylation of extracellular-signal-regulated kinase proteins downstream of BRAF and suppressed cell growth in vitro and in vivo. Furthermore, siRNAs with 2′-O-methyl modifications at positions 2–5 reduce the seed-dependent off-target effects, as confirmed by reporter and microarray analyses. Thus, such siRNA is a promising candidate therapy for 15-bp deletion-type BRAF-induced tumorigenesis.
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Schlegel MK, Janas MM, Jiang Y, Barry JD, Davis W, Agarwal S, Berman D, Brown CR, Castoreno A, LeBlanc S, Liebow A, Mayo T, Milstein S, Nguyen T, Shulga-Morskaya S, Hyde S, Schofield S, Szeto J, Woods L, Yilmaz V, Manoharan M, Egli M, Charissé K, Sepp-Lorenzino L, Haslett P, Fitzgerald K, Jadhav V, Maier M. From bench to bedside: Improving the clinical safety of GalNAc-siRNA conjugates using seed-pairing destabilization. Nucleic Acids Res 2022; 50:6656-6670. [PMID: 35736224 PMCID: PMC9262600 DOI: 10.1093/nar/gkac539] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 06/02/2022] [Accepted: 06/09/2022] [Indexed: 12/24/2022] Open
Abstract
Preclinical mechanistic studies have pointed towards RNA interference-mediated off-target effects as a major driver of hepatotoxicity for GalNAc-siRNA conjugates. Here, we demonstrate that a single glycol nucleic acid or 2'-5'-RNA modification can substantially reduce small interfering RNA (siRNA) seed-mediated binding to off-target transcripts while maintaining on-target activity. In siRNAs with established hepatotoxicity driven by off-target effects, these novel designs with seed-pairing destabilization, termed enhanced stabilization chemistry plus (ESC+), demonstrated a substantially improved therapeutic window in rats. In contrast, siRNAs thermally destabilized to a similar extent by the incorporation of multiple DNA nucleotides in the seed region showed little to no improvement in rat safety suggesting that factors in addition to global thermodynamics play a role in off-target mitigation. We utilized the ESC+ strategy to improve the safety of ALN-HBV, which exhibited dose-dependent, transient and asymptomatic alanine aminotransferase elevations in healthy volunteers. The redesigned ALN-HBV02 (VIR-2218) showed improved specificity with comparable on-target activity and the program was reintroduced into clinical development.
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Affiliation(s)
| | | | | | | | - Wendell Davis
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | - Saket Agarwal
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | - Daniel Berman
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | | | | | - Sarah LeBlanc
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | | | - Tara Mayo
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | | | - Tuyen Nguyen
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | | | - Sarah Hyde
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | | | - John Szeto
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | | | | | | | - Martin Egli
- Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, TN 37232, USA
| | | | | | | | | | - Vasant Jadhav
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | - Martin A Maier
- To whom correspondence should be addressed: Tel: +1 617 551 8274; Fax: +1 617 682 4020;
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8
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Shiohama Y, Fujita R, Sonokawa M, Hisano M, Kotake Y, Krstic-Demonacos M, Demonacos C, Kashiwazaki G, Kitayama T, Fujii M. Elimination of Off-Target Effect by Chemical Modification of 5′-End of Small Interfering RNA. Nucleic Acid Ther 2022; 32:438-447. [DOI: 10.1089/nat.2021.0068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Yasuo Shiohama
- Environmental and Biological Information Group, Tropical Biosphere Research Centre, University of the Ryukyus, Nishihara, Japan
| | - Ryosuke Fujita
- Department of Biological & Environmental Chemistry, School of Humanity Oriented Science and Technology, Kindai University, Iizuka, Japan
| | - Maika Sonokawa
- Department of Biological & Environmental Chemistry, School of Humanity Oriented Science and Technology, Kindai University, Iizuka, Japan
| | - Masaaki Hisano
- Department of Biological & Environmental Chemistry, School of Humanity Oriented Science and Technology, Kindai University, Iizuka, Japan
| | - Yojiro Kotake
- Department of Biological & Environmental Chemistry, School of Humanity Oriented Science and Technology, Kindai University, Iizuka, Japan
| | - Marija Krstic-Demonacos
- School of Science, Engineering and Environment, University of Salford, Salford, United Kingdom
| | - Constantinos Demonacos
- Division of Pharmacy and Optometry, Faculty of Biology Medicine and Health, School of Health Science, University of Manchester, Manchester, United Kingdom
| | - Gengo Kashiwazaki
- Department of Advanced Bioscience, Faculty of Agriculture, Kindai University, Nara, Japan
| | - Takashi Kitayama
- Department of Advanced Bioscience, Faculty of Agriculture, Kindai University, Nara, Japan
| | - Masayuki Fujii
- Department of Biological & Environmental Chemistry, School of Humanity Oriented Science and Technology, Kindai University, Iizuka, Japan
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9
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Li Y, Bao Q, Yang S, Yang M, Mao C. Bionanoparticles in cancer imaging, diagnosis, and treatment. VIEW 2022. [DOI: 10.1002/viw.20200027] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Affiliation(s)
- Yan Li
- Institute of Applied Bioresource Research College of Animal Science Zhejiang University Hangzhou Zhejiang China
| | - Qing Bao
- School of Materials Science and Engineering Zhejiang University Hangzhou Zhejiang China
| | - Shuxu Yang
- Department of Neurosurgery Sir Run Run Shaw Hospital School of Medicine Zhejiang University Hangzhou Zhejiang China
| | - Mingying Yang
- Institute of Applied Bioresource Research College of Animal Science Zhejiang University Hangzhou Zhejiang China
| | - Chuanbin Mao
- School of Materials Science and Engineering Zhejiang University Hangzhou Zhejiang China
- Department of Chemistry and Biochemistry Stephenson Life Science Research Center University of Oklahoma Norman Oklahoma USA
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IMAI K, TANIGUCHI H. Therapeutic siRNA targeting the cancer cell stemness regulator PRDI-BF1 and RIZ domain zinc finger protein 14. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2022; 98:325-335. [PMID: 35908955 PMCID: PMC9363597 DOI: 10.2183/pjab.98.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 05/11/2022] [Indexed: 06/15/2023]
Abstract
PRDI-BF1 and RIZ (PR) domain zinc finger protein 14 (PRDM14), first reported in 2007 to be overexpressed in breast cancer, plays an important role in breast cancer proliferation. Subsequent studies reported that PRDM14 is expressed in embryonic stem cells, primordial germ cells, and various cancers. PRDM14 was reported to confer stemness properties to cancer cells. These properties induce cancer initiation, cancer progression, therapeutic resistance, distant metastasis, and recurrence in refractory tumors. Therefore, PRDM14 may be an ideal therapeutic target for various types of tumors. Silencing PRDM14 expression using PRDM14-specific siRNA delivered through an innovative intravenous drug delivery system reduced the size of inoculated tumors, incidence of distant metastases, and increased overall survival in nude mice without causing adverse effects. Therapeutic siRNA targeting PRDM14 is now being evaluated in a human phase I clinical trial for patients with refractory breast cancer, including triple-negative breast cancer.
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Affiliation(s)
- Kohzoh IMAI
- Institute for Genetic Medicine, Hokkaido University, Sapporo, Hokkaido, Japan
| | - Hiroaki TANIGUCHI
- Keio Cancer Center, Keio University School of Medicine, Tokyo, Japan
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Senichkin VV, Pervushin NV, Zamaraev AV, Sazonova EV, Zuev AP, Streletskaia AY, Prikazchikova TA, Zatsepin TS, Kovaleva OV, Tchevkina EM, Zhivotovsky B, Kopeina GS. Bak and Bcl-xL Participate in Regulating Sensitivity of Solid Tumor Derived Cell Lines to Mcl-1 Inhibitors. Cancers (Basel) 2021; 14:cancers14010181. [PMID: 35008345 PMCID: PMC8750033 DOI: 10.3390/cancers14010181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 12/15/2021] [Accepted: 12/20/2021] [Indexed: 11/16/2022] Open
Abstract
Simple Summary Apoptosis is one of the best-known types of programmed cell death. This process is regulated by a number of genes and proteins, among which the Bcl-2 protein family plays a key role. This family includes anti- and proapoptotic proteins. Cancer cell resistance to apoptosis is commonly associated with overexpression of the antiapoptotic members of Bcl-2 family proteins, in particular, Bcl-2, Bcl-xL, and Mcl-1. Subsequently, these proteins represent perspective targets for anticancer therapy. Here, using an inhibitory approach, we found that Bak and Bcl-xL regulate sensitivity of cancer cells to Mcl-1 inhibition. Abstract BH3 mimetics represent a promising tool in cancer treatment. Recently, the drugs targeting the Mcl-1 protein progressed into clinical trials, and numerous studies are focused on the investigation of their activity in various preclinical models. We investigated two BH3 mimetics to Mcl-1, A1210477 and S63845, and found their different efficacies in on-target doses, despite the fact that both agents interacted with the target. Thus, S63845 induced apoptosis more effectively through a Bak-dependent mechanism. There was an increase in the level of Bcl-xL protein in cells with acquired resistance to Mcl-1 inhibition. Cell lines sensitive to S63845 demonstrated low expression of Bcl-xL. Tumor tissues from patients with lung adenocarcinoma were characterized by decreased Bcl-xL and increased Bak levels of both mRNA and proteins. Concomitant inhibition of Bcl-xL and Mcl-1 demonstrated dramatic cytotoxicity in six of seven studied cell lines. We proposed that co-targeting Bcl-xL and Mcl-1 might lead to a release of Bak, which cannot be neutralized by other anti-apoptotic proteins. Surprisingly, in Bak-knockout cells, inhibition of Mcl-1 and Bcl-xL still resulted in pronounced cell death, arguing against a sole role of Bak in the studied phenomenon. We demonstrate that Bak and Bcl-xL are co-factors for, respectively, sensitivity and resistance to Mcl-1 inhibition.
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Affiliation(s)
- Viacheslav V. Senichkin
- Faculty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; (V.V.S.); (N.V.P.); (A.V.Z.); (E.V.S.); (A.P.Z.); (A.Y.S.)
| | - Nikolay V. Pervushin
- Faculty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; (V.V.S.); (N.V.P.); (A.V.Z.); (E.V.S.); (A.P.Z.); (A.Y.S.)
| | - Alexey V. Zamaraev
- Faculty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; (V.V.S.); (N.V.P.); (A.V.Z.); (E.V.S.); (A.P.Z.); (A.Y.S.)
| | - Elena V. Sazonova
- Faculty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; (V.V.S.); (N.V.P.); (A.V.Z.); (E.V.S.); (A.P.Z.); (A.Y.S.)
| | - Anton P. Zuev
- Faculty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; (V.V.S.); (N.V.P.); (A.V.Z.); (E.V.S.); (A.P.Z.); (A.Y.S.)
| | - Alena Y. Streletskaia
- Faculty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; (V.V.S.); (N.V.P.); (A.V.Z.); (E.V.S.); (A.P.Z.); (A.Y.S.)
| | | | - Timofei S. Zatsepin
- Skolkovo Institute of Science and Technology, 121205 Skolkovo, Russia; (T.A.P.); (T.S.Z.)
- Faculty of Chemistry, MV Lomonosov Moscow State University, 119991 Moscow, Russia
| | - Olga V. Kovaleva
- NN Blokhin Russian Cancer Research Center, Department of Oncogenes Regulation, 115478 Moscow, Russia; (O.V.K.); (E.M.T.)
| | - Elena M. Tchevkina
- NN Blokhin Russian Cancer Research Center, Department of Oncogenes Regulation, 115478 Moscow, Russia; (O.V.K.); (E.M.T.)
| | - Boris Zhivotovsky
- Faculty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; (V.V.S.); (N.V.P.); (A.V.Z.); (E.V.S.); (A.P.Z.); (A.Y.S.)
- Institute of Environmental Medicine, Karolinska Institutet, 17177 Stockholm, Sweden
- Correspondence: (B.Z.); (G.S.K.)
| | - Gelina S. Kopeina
- Faculty of Medicine, MV Lomonosov Moscow State University, 119991 Moscow, Russia; (V.V.S.); (N.V.P.); (A.V.Z.); (E.V.S.); (A.P.Z.); (A.Y.S.)
- Correspondence: (B.Z.); (G.S.K.)
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12
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Rahman A, Gupta SD, Rahman MA, Tamanna S. An in-silico approach to design potential siRNAs against the ORF57 of Kaposi's sarcoma-associated herpesvirus. Genomics Inform 2021; 19:e47. [PMID: 35012290 PMCID: PMC8752988 DOI: 10.5808/gi.21057] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 11/25/2021] [Accepted: 12/09/2021] [Indexed: 12/21/2022] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) is one of the few human oncogenic viruses, which causes a variety of malignancies, including Kaposi's sarcoma, multicentric Castleman disease, and primary effusion lymphoma, particularly in human immunodeficiency virus patients. The currently available treatment options cannot always prevent the invasion and dissemination of this virus. In recent times, siRNA-based therapeutics are gaining prominence over conventional medications as siRNA can be designed to target almost any gene of interest. The ORF57 is a crucial regulatory protein for lytic gene expression of KSHV. Disruption of this gene translation will inevitably inhibit the replication of the virus in the host cell. Therefore, the ORF57 of KSHV could be a potential target for designing siRNA-based therapeutics. Considering both sequence preferences and target site accessibility, several online tools (i-SCORE Designer, Sfold web server) had been utilized to predict the siRNA guide strand against the ORF57. Subsequently, off-target filtration (BLAST), conservancy test (fuzznuc), and thermodynamics analysis (RNAcofold, RNAalifold, and RNA Structure web server) were also performed to select the most suitable siRNA sequences. Finally, two siRNAs were identified that passed all of the filtration phases and fulfilled the thermodynamic criteria. We hope that the siRNAs predicted in this study would be helpful for the development of new effective therapeutics against KSHV.
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Affiliation(s)
- Anisur Rahman
- Department of Biotechnology and Genetic Engineering, Faculty of Science, Noakhali Science and Technology University, Noakhali 3814, Bangladesh
| | - Shipan Das Gupta
- Department of Biotechnology and Genetic Engineering, Faculty of Science, Noakhali Science and Technology University, Noakhali 3814, Bangladesh
| | - Md. Anisur Rahman
- Department of Biotechnology and Genetic Engineering, Faculty of Science, Noakhali Science and Technology University, Noakhali 3814, Bangladesh
| | - Saheda Tamanna
- Department of Biotechnology and Genetic Engineering, Faculty of Science, Noakhali Science and Technology University, Noakhali 3814, Bangladesh
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13
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Ageely EA, Chilamkurthy R, Jana S, Abdullahu L, O'Reilly D, Jensik PJ, Damha MJ, Gagnon KT. Gene editing with CRISPR-Cas12a guides possessing ribose-modified pseudoknot handles. Nat Commun 2021; 12:6591. [PMID: 34782635 PMCID: PMC8593028 DOI: 10.1038/s41467-021-26989-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 11/01/2021] [Indexed: 12/26/2022] Open
Abstract
CRISPR-Cas12a is a leading technology for development of model organisms, therapeutics, and diagnostics. These applications could benefit from chemical modifications that stabilize or tune enzyme properties. Here we chemically modify ribonucleotides of the AsCas12a CRISPR RNA 5' handle, a pseudoknot structure that mediates binding to Cas12a. Gene editing in human cells required retention of several native RNA residues corresponding to predicted 2'-hydroxyl contacts. Replacing these RNA residues with a variety of ribose-modified nucleotides revealed 2'-hydroxyl sensitivity. Modified 5' pseudoknots with as little as six out of nineteen RNA residues, with phosphorothioate linkages at remaining RNA positions, yielded heavily modified pseudoknots with robust cell-based editing. High trans activity was usually preserved with cis activity. We show that the 5' pseudoknot can tolerate near complete modification when design is guided by structural and chemical compatibility. Rules for modification of the 5' pseudoknot should accelerate therapeutic development and be valuable for CRISPR-Cas12a diagnostics.
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Affiliation(s)
- Eman A Ageely
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL, USA
| | - Ramadevi Chilamkurthy
- Department of Biochemistry and Molecular Biology, School of Medicine, Southern Illinois University, Carbondale, IL, USA
| | - Sunit Jana
- Department of Chemistry, McGill University, Montreal, Canada
| | | | - Daniel O'Reilly
- Department of Chemistry, McGill University, Montreal, Canada
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA, USA
| | - Philip J Jensik
- Department of Physiology, School of Medicine, Southern Illinois University, Carbondale, IL, USA
| | - Masad J Damha
- Department of Chemistry, McGill University, Montreal, Canada.
| | - Keith T Gagnon
- Department of Chemistry and Biochemistry, Southern Illinois University, Carbondale, IL, USA.
- Department of Biochemistry and Molecular Biology, School of Medicine, Southern Illinois University, Carbondale, IL, USA.
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14
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Schlegel MK, Matsuda S, Brown CR, Harp JM, Barry JD, Berman D, Castoreno A, Schofield S, Szeto J, Manoharan M, Charissé K, Egli M, Maier MA. Overcoming GNA/RNA base-pairing limitations using isonucleotides improves the pharmacodynamic activity of ESC+ GalNAc-siRNAs. Nucleic Acids Res 2021; 49:10851-10867. [PMID: 34648028 PMCID: PMC8565336 DOI: 10.1093/nar/gkab916] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 09/19/2021] [Accepted: 09/27/2021] [Indexed: 11/30/2022] Open
Abstract
We recently reported that RNAi-mediated off-target effects are important drivers of the hepatotoxicity observed for a subset of GalNAc–siRNA conjugates in rodents, and that these findings could be mitigated by seed-pairing destabilization using a single GNA nucleotide placed within the seed region of the guide strand. Here, we report further investigation of the unique and poorly understood GNA/RNA cross-pairing behavior to better inform GNA-containing siRNA design. A reexamination of published GNA homoduplex crystal structures, along with a novel structure containing a single (S)-GNA-A residue in duplex RNA, indicated that GNA nucleotides universally adopt a rotated nucleobase orientation within all duplex contexts. Such an orientation strongly affects GNA-C and GNA-G but not GNA-A or GNA-T pairing in GNA/RNA heteroduplexes. Transposition of the hydrogen-bond donor/acceptor pairs using the novel (S)-GNA-isocytidine and -isoguanosine nucleotides could rescue productive base-pairing with the complementary G or C ribonucleotides, respectively. GalNAc-siRNAs containing these GNA isonucleotides showed an improved in vitro activity, a similar improvement in off-target profile, and maintained in vivo activity and guide strand liver levels more consistent with the parent siRNAs than those modified with isomeric GNA-C or -G, thereby expanding our toolbox for the design of siRNAs with minimized off-target activity.
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Affiliation(s)
| | | | | | - Joel M Harp
- Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, TN 37232, USA
| | | | - Daniel Berman
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | | | | | - John Szeto
- Alnylam Pharmaceuticals, Inc., Cambridge, MA 02142, USA
| | | | | | - Martin Egli
- Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, TN 37232, USA
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15
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Taniguchi H, Natori Y, Miyagi Y, Hayashi K, Nagamura F, Kataoka K, Imai K. Treatment of primary and metastatic breast and pancreatic tumors upon intravenous delivery of a PRDM14-specific chimeric siRNA/nanocarrier complex. Int J Cancer 2021; 149:646-656. [PMID: 33783816 DOI: 10.1002/ijc.33579] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 01/10/2021] [Accepted: 02/09/2021] [Indexed: 01/28/2023]
Abstract
PRDM14 is highly expressed in several cancers but is not detected in normal tissues. It confers cancer stem cell-like properties, including chemoresistance and distant metastasis, to cancer cells. Herein, we aimed to develop a highly effective therapy against advanced stage cancer based on intravenously delivered PRDM14-targeted siRNA. First, we examined PRDM14 expression and gene amplification in breast and pancreatic tumors and cell lines. PRDM14 was expressed in breast cancer, including the triple-negative subtype, and pancreatic cancer. PRDM14 was amplified in 23.8% of patients with PRDM14+ breast cancer. Next, we investigated the inoculated tumor growth and distant metastasis following PRDM14 depletion by administering mice with PRDM14-specific chimeric siRNA combined with a novel branched PEGylated poly-L-ornithine (PLO)-based intravenous drug delivery system, designated PRDM14 unit polyion complex (uPIC) (n = 6/group). Inhibition of PRDM14 expression with PRDM14 uPIC by systemic intravenous injection effectively reduced tumor size and metastasis in vivo, thereby improving survival. Finally, pharmacokinetic/toxicokinetic analyses were performed on PRDM14 uPIC, which was intravenously administered to rats (n = 10-15/group) and cynomolgus monkeys (n = 3-5/group), twice weekly for 4 weeks. This revealed that PRDM14 uPIC was relatively nontoxic and the siRNA exposure in serum was greater than that predicted by the administered dose ratio when delivered as a uPIC. Taken together, our study indicated that PRDM14 uPIC is highly effective in suppressing malignant features of solid cancers and does not cause severe toxicity, making it a promising therapeutic agent for cancer treatment.
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Affiliation(s)
- Hiroaki Taniguchi
- The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.,Keio Cancer Center, Keio University School of Medicine, Tokyo, Japan.,Research and Development Center for Precision Medicine, University of Tsukuba, Innovation Medical Research Institute, Ibaraki, Japan
| | - Yukikazu Natori
- Keio Cancer Center, Keio University School of Medicine, Tokyo, Japan.,BioThinkTank Co. Ltd., Nishi-ku Yokohama, Kanagawa, Japan
| | - Yohei Miyagi
- Molecular Pathology and Genetics Division, Kanagawa Cancer Center Research Institute, Yokohama, Kanagawa, Japan
| | - Kotaro Hayashi
- Innovation Center of NanoMedicine, Kawasaki Institute of Industrial Promotion, Kawasaki City, Kanagawa Prefecture, Japan
| | - Fumitaka Nagamura
- Translational Research Center, Research Hospital, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - Kazunori Kataoka
- Innovation Center of NanoMedicine, Kawasaki Institute of Industrial Promotion, Kawasaki City, Kanagawa Prefecture, Japan.,Institute for Future Initiatives, The University of Tokyo, Tokyo, Japan
| | - Kohzoh Imai
- Institute for Genetic Medicine, Hokkaido University, Sapporo, Japan
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16
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Hossain MU, Bhattacharjee A, Emon MTH, Chowdhury ZM, Mosaib MG, Mourin M, Das KC, Keya CA, Salimullah M. Recognition of plausible therapeutic agents to combat COVID-19: An omics data based combined approach. Gene 2021; 771:145368. [PMID: 33346100 PMCID: PMC7833977 DOI: 10.1016/j.gene.2020.145368] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/03/2020] [Accepted: 12/11/2020] [Indexed: 02/07/2023]
Abstract
Coronavirus disease-2019 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), has become an immense threat to global public health. In this study, we performed complete genome sequencing of a SARS-CoV-2 isolate. More than 67,000 genome sequences were further inspected from Global Initiative on Sharing All Influenza Data (GISAID). Using several in silico techniques, we proposed prospective therapeutics against this virus. Through meticulous analysis, several conserved and therapeutically suitable regions of SARS-CoV-2 such as RNA-dependent RNA polymerase (RdRp), Spike (S) and Membrane glycoprotein (M) coding genes were selected. Both S and M were chosen for the development of a chimeric vaccine that can generate memory B and T cells. siRNAs were also designed for S and M gene silencing. Moreover, six new drug candidates were suggested that might inhibit the activity of RdRp. Since SARS-CoV-2 and SARS-CoV-1 have 82.30% sequence identity, a Gene Expression Omnibus (GEO) dataset of Severe Acute Respiratory Syndrome (SARS) patients were analyzed. In this analysis, 13 immunoregulatory genes were found that can be used to develop type 1 interferon (IFN) based therapy. The proposed vaccine, siRNAs, drugs and IFN based analysis of this study will accelerate the development of new treatments.
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Affiliation(s)
- Mohammad Uzzal Hossain
- Bioinformatics Division, National Institute of Biotechnology, Ganakbari, Ashulia, Savar, Dhaka 1349, Bangladesh
| | - Arittra Bhattacharjee
- Bioinformatics Division, National Institute of Biotechnology, Ganakbari, Ashulia, Savar, Dhaka 1349, Bangladesh; Department of Biochemistry and Microbiology, North South University, Bashundhara, Dhaka 1229, Bangladesh
| | - Md Tabassum Hossain Emon
- Department of Biotechnology and Genetic Engineering, Life Science Faculty, Mawlana Bhashani Science and Technology University, Santosh, Tangail 1902, Bangladesh
| | - Zeshan Mahmud Chowdhury
- Department of Biochemistry and Microbiology, North South University, Bashundhara, Dhaka 1229, Bangladesh
| | - Md Golam Mosaib
- Department of Biochemistry and Molecular Biology, Faculty of Health & Medical Sciences, Gono Bishwabidyaloy, Ashulia, Savar, Dhaka 1344, Bangladesh
| | - Muntahi Mourin
- Department of Biochemistry and Microbiology, North South University, Bashundhara, Dhaka 1229, Bangladesh; Department of Microbiology, University of Manitoba, 66 Chancellors Cir, Winnipeg, MB R3T 2N2, Canada
| | - Keshob Chandra Das
- Molecular Biotechnology Division, National Institute of Biotechnology, Ganakbari, Ashulia, Savar, Dhaka 1349, Bangladesh
| | - Chaman Ara Keya
- Department of Biochemistry and Microbiology, North South University, Bashundhara, Dhaka 1229, Bangladesh
| | - Md Salimullah
- Molecular Biotechnology Division, National Institute of Biotechnology, Ganakbari, Ashulia, Savar, Dhaka 1349, Bangladesh.
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17
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Kobayashi Y, Miyamoto K, Aida M, Ui-Tei K. Selection of Chemical Modifications in the siRNA Seed Region That Repress Off-Target Effect. Methods Mol Biol 2021; 2282:17-30. [PMID: 33928567 DOI: 10.1007/978-1-0716-1298-9_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
RNA interference mediated by small interfering RNA (siRNA) has been widely used as a procedure to knock down the expression of an intended target gene with perfect sequence complementarity. However, siRNA often exhibits off-target effects on genes with partial sequence complementarities. Such off-target effect is an undesirable adverse effect for knocking down a target gene specifically. Here we describe the powerful strategy to avoid off-target effects without affecting the RNAi activity by the introduction of DNA or 2'-O-methyl modifications in the siRNA seed region. These two types of chemical modifications repress off-target effects through different molecular mechanisms.
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Affiliation(s)
- Yoshiaki Kobayashi
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan
| | - Kengo Miyamoto
- Center for Quantum Life Sciences and Department of Chemistry, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan
| | - Misako Aida
- Center for Quantum Life Sciences and Department of Chemistry, Graduate School of Science, Hiroshima University, Higashi-Hiroshima, Japan
| | - Kumiko Ui-Tei
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
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18
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Streletskaia AY, Senichkin VV, Prikazchikova TA, Zatsepin TS, Zhivotovsky B, Kopeina GS. Upregulation of Mcl-1S Causes Cell-Cycle Perturbations and DNA Damage Accumulation. Front Cell Dev Biol 2020; 8:543066. [PMID: 33072738 PMCID: PMC7544834 DOI: 10.3389/fcell.2020.543066] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 08/19/2020] [Indexed: 12/04/2022] Open
Abstract
As an important regulator of apoptosis, Mcl-1 protein, a member of the Bcl-2 family, represents an attractive target for cancer treatment. The recent development of novel small molecule compounds has allowed Mcl-1-inhibitory therapy to proceed to clinical trials in cancer treatment. However, the possible adverse effects of either direct inhibition of Mcl-1 or upregulation of Mcl-1S, proapoptotic isoform resulting from alternative splicing of Mcl-1, remain unclear. Here, we investigated changes in Mcl-1S levels during cell cycle and the cell cycle-related functions of Mcl-1 isoforms to address the above-mentioned concerns. It was shown that an anti-mitotic agent monastrol caused accumulation of Mcl-1S mRNA, although without increasing the protein level. In contrast, both mRNA and protein levels of Mcl-1S accrued during the premitotic stages of the normal cell cycle progression. Importantly, Mcl-1S was observed in the nuclear compartment and an overexpression of Mcl-1S, as well as knockdown of Mcl-1, accelerated the progression of cells into mitosis and resulted in DNA damage accumulation. Surprisingly, a small molecule inhibitor of Mcl-1, BH3-mimetic S63845, did not affect the cell cycle progression or the amount of DNA damage. In general, upregulated Mcl-1S protein or genetically inhibited Mcl-1L were associated with the cell cycle perturbations and DNA damage accumulation in normal and cancer cells. At the same time, BH3-mimetic to Mcl-1 did not affect the cell cycle progression, suggesting that direct inhibition of Mcl-1 is devoid of cell-cycle related undesired effects.
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Affiliation(s)
| | | | | | - Timofei S Zatsepin
- Faculty of Medicine, MV Lomonosov Moscow State University, Moscow, Russia.,Skolkovo Institute of Science and Technology, Skolkovo, Russia
| | - Boris Zhivotovsky
- Faculty of Medicine, MV Lomonosov Moscow State University, Moscow, Russia.,Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Gelina S Kopeina
- Faculty of Medicine, MV Lomonosov Moscow State University, Moscow, Russia
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19
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Tsubaki K, Hammill ML, Varley AJ, Kitamura M, Okauchi T, Desaulniers JP. Synthesis and Evaluation of Neutral Phosphate Triester Backbone-Modified siRNAs. ACS Med Chem Lett 2020; 11:1457-1462. [PMID: 32676154 DOI: 10.1021/acsmedchemlett.0c00232] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/09/2020] [Indexed: 11/30/2022] Open
Abstract
Two unsymmetrical dinucleotide phosphate triesters were synthesized via transesterification from tris(2,2,2-trifluoroethyl) phosphate. The protected triesters were phosphytilated to generate phosphoramidites for solid-phase oligonucleotide synthesis. Neutral phenylethyl phosphate-modified short-interfering RNAs (siRNAs) were synthesized and evaluated for their gene-silencing ability, siRNA strand selection, and resistance to nucleases. These backbone-modified phosphate triester siRNAs offer many improvements compared to natural unmodified siRNAs.
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Affiliation(s)
- Kouta Tsubaki
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu Institute of Technology, 1-1 Sensui-cho, Tobata, Kitakyushu 804-8550, Japan
- Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ontario L1G 0C5, Canada
| | - Matthew L. Hammill
- Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ontario L1G 0C5, Canada
| | - Andrew J. Varley
- Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ontario L1G 0C5, Canada
| | - Mitsuru Kitamura
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu Institute of Technology, 1-1 Sensui-cho, Tobata, Kitakyushu 804-8550, Japan
| | - Tatsuo Okauchi
- Department of Applied Chemistry, Graduate School of Engineering, Kyushu Institute of Technology, 1-1 Sensui-cho, Tobata, Kitakyushu 804-8550, Japan
| | - Jean-Paul Desaulniers
- Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ontario L1G 0C5, Canada
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20
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Le T, Winham CL, Andromidas F, Silver AC, Jellison ER, Levesque AA, Koob AO. Chimera RNA interference knockdown of γ-synuclein in human cortical astrocytes results in mitotic catastrophe. Neural Regen Res 2020; 15:1894-1902. [PMID: 32246638 PMCID: PMC7513975 DOI: 10.4103/1673-5374.280329] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Elevated levels of γ-synuclein (γ-syn) expression have been noted in the progression of glioblastomas, and also in the cerebrospinal fluid of patients diagnosed with neurodegenerative diseases. γ-Syn can be either internalized from the extracellular milieu or expressed endogenously by human cortical astrocytes. Internalized γ-syn results in increased cellular proliferation, brain derived neurotrophic factor release and astroprotection. However, the function of endogenous γ-syn in primary astrocytes, and the relationship to these two opposing disease states are unknown. γ-Syn is expressed by astrocytes in the human cortex, and to gain a better understanding of the role of endogenous γ-syn, primary human cortical astrocytes were treated with chimera RNA interference (RNAi) targeting γ-syn after release from cell synchronization. Quantitative polymerase chain reaction analysis demonstrated an increase in endogenous γ-syn expression 48 hours after release from cell synchronization, while RNAi reduced γ-syn expression to control levels. Immunocytochemistry of Ki67 and 5-bromodeoxyuridine showed chimera RNAi γ-syn knockdown reduced cellular proliferation at 24 and 48 hours after release from cell synchronization. To further investigate the consequence of γ-syn knockdown on the astrocytic cell cycle, phosphorylated histone H3 pSer10 (pHH3) and phosphorylated cyclin dependent kinase-2 pTyr15 (pCDK2) levels were observed via western blot analysis. The results revealed an elevated expression of pHH3, but not pCDK2, indicating γ-syn knockdown leads to disruption of the cell cycle and chromosomal compaction after 48 hours. Subsequently, flow cytometry with propidium iodide determined that increases in apoptosis coincided with γ-syn knockdown. Therefore, γ-syn exerts its effect to allow normal astrocytic progression through the cell cycle, as evidenced by decreased proliferation marker expression, increased pHH3, and mitotic catastrophe after knockdown. In this study, we demonstrated that the knockdown of γ-syn within primary human cortical astrocytes using chimera RNAi leads to cell cycle disruption and apoptosis, indicating an essential role for γ-syn in regulating normal cell division in astrocytes. Therefore, disruption to γ-syn function would influence astrocytic proliferation, and could be an important contributor to neurological diseases.
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Affiliation(s)
- Timmy Le
- Graduate Program in Neuroscience, Biology Department, University of Hartford, West Hartford, CT, USA
| | - Cynthia L Winham
- Graduate Program in Neuroscience, Biology Department, University of Hartford, West Hartford, CT, USA
| | - Fotis Andromidas
- Graduate Program in Neuroscience, Biology Department, University of Hartford, West Hartford, CT, USA
| | - Adam C Silver
- Graduate Program in Neuroscience, Biology Department, University of Hartford, West Hartford, CT, USA
| | - Evan R Jellison
- Department of Immunology, UCONN Health Center, Farmington, CT, USA
| | - Aime A Levesque
- Graduate Program in Neuroscience, Biology Department, University of Hartford, West Hartford, CT, USA
| | - Andrew O Koob
- Graduate Program in Neuroscience, Biology Department, University of Hartford, West Hartford, CT, USA
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21
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Lennox KA, Behlke MA. Chemical Modifications in RNA Interference and CRISPR/Cas Genome Editing Reagents. Methods Mol Biol 2020; 2115:23-55. [PMID: 32006393 DOI: 10.1007/978-1-0716-0290-4_2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Chemically modified oligonucleotides (ONs) are routinely used in the laboratory to assess gene function, and clinical advances are rapidly progressing as continual efforts are being made to optimize ON efficacy. Over the years, RNA interference (RNAi) has become one of the main tools used to inhibit RNA expression across a wide variety of species. Efforts have been made to improve the exogenous delivery of the double-stranded RNA components to the endogenous intracellular RNAi machinery to direct efficacious degradation of a user-defined RNA target. More recently, synthetic RNA ONs are being used to mimic the bacterial-derived CRISPR/Cas system to direct specific editing of the mammalian genome. Both of these techniques rely on the use of various chemical modifications to the RNA phosphate backbone or sugar in specific positions throughout the ONs to improve the desired biological outcome. Relevant chemical modifications also include conjugated targeting ligands to assist ON delivery to specific cell types. Chemical modifications are most beneficial for therapeutically relevant ONs, as they serve to enhance target binding, increase drug longevity, facilitate cell-specific targeting, improve internalization into productive intracellular compartments, and mitigate both sequence-specific as well as immune-related off-target effects (OTEs). The knowledge gained from years of optimizing RNAi reagents and characterizing the biochemical and biophysical properties of each chemical modification will hopefully accelerate the CRISPR/Cas technology into the clinic, as well as further expand the use of RNAi to treat currently undruggable diseases. This review discusses the most commonly employed chemical modifications in RNAi reagents and CRISPR/Cas guide RNAs and provides an overview of select publications that have demonstrated success in improving ON efficacy and/or mitigating undesired OTEs.
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Affiliation(s)
- Kim A Lennox
- Integrated DNA Technologies, Inc., Coralville, IA, USA.
| | - Mark A Behlke
- Integrated DNA Technologies, Inc., Coralville, IA, USA
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22
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Silencing PRDM14 via Oligonucleotide Therapeutics Suppresses Tumorigenicity and Metastasis of Breast Cancer. Methods Mol Biol 2019; 1974:233-243. [PMID: 31099008 DOI: 10.1007/978-1-4939-9220-1_18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The PRDI-BF1 and RIZ (PR) domain zinc finger protein 14 (PRDM14) is upregulated in approximately 60% of breast cancers, some of which exhibit gene amplification. In contrast, PRDM14 is not expressed in normal, and differentiated tissues. PRDM14+ breast cancer cells are resistant to chemotherapy drugs, are tumorigenic, and metastasize to the lungs. It is commonly assumed that genes that are overexpressed in cancers, such as PRDM14, are effective targets for new therapies that specifically abrogate the expression of these genes. RNA interference of PRDM14, a gene expressed by breast cancer cells, reduced the size of tumors and lung metastases in nude mice. In this chapter, we introduce the concept and methods to develop and apply systematically injected small interfering RNA therapy for breast cancer models in vivo.
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23
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Koizumi M, Hirota Y, Nakayama M, Tamura M, Obuchi W, Kurimoto A, Tsuchida H, Maeda H. Design of 2'- O-methyl RNA and DNA double-stranded oligonucleotides: naturally-occurring nucleotide components with strong RNA interference gene expression inhibitory activity. NUCLEOSIDES NUCLEOTIDES & NUCLEIC ACIDS 2019; 39:292-309. [PMID: 31509065 DOI: 10.1080/15257770.2019.1663384] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Double-stranded RNAs consisting of 21-nucleotide passenger and guide strands, known as small interfering RNAs (siRNAs), can be used for the identification of gene functions and the regulation of genes involved in disease for therapeutics. The difficulty with unmodified siRNAs lies in the chemical synthesis of RNA, its degradation by RNase, the immune response derived from natural RNA, and the off-target effects mediated by the passenger strand. In this study, asymmetrical 18 base-paired double-strand oligonucleotides comprised of alternately combined DNAs and 2'-O-methyl RNAs, denoted as MED-siRNA, were evaluated. These modified oligonucleotides showed high RNase resistance, a reduced immune response, a highly efficient cleavage of target mRNA with binding to Argonaute 2 (Ago2) via RNA interference, and the subsequent reduction of target protein expression. These findings suggest the possibility of alternatives to unmodified siRNAs with potential use in therapeutics.
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Affiliation(s)
- Makoto Koizumi
- R&D and Biologics Divisions, Daiichi Sankyo Co. Ltd, Shinagawa, Tokyo, Japan
| | - Yasuhide Hirota
- R&D and Biologics Divisions, Daiichi Sankyo Co. Ltd, Shinagawa, Tokyo, Japan
| | - Makiko Nakayama
- R&D and Biologics Divisions, Daiichi Sankyo Co. Ltd, Shinagawa, Tokyo, Japan
| | - Masakazu Tamura
- R&D and Biologics Divisions, Daiichi Sankyo Co. Ltd, Shinagawa, Tokyo, Japan
| | - Wataru Obuchi
- R&D and Biologics Divisions, Daiichi Sankyo Co. Ltd, Shinagawa, Tokyo, Japan
| | - Akiko Kurimoto
- R&D and Biologics Divisions, Daiichi Sankyo Co. Ltd, Shinagawa, Tokyo, Japan
| | - Hiroshi Tsuchida
- R&D and Biologics Divisions, Daiichi Sankyo Co. Ltd, Shinagawa, Tokyo, Japan
| | - Hiroaki Maeda
- R&D and Biologics Divisions, Daiichi Sankyo Co. Ltd, Shinagawa, Tokyo, Japan
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24
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Vu AL, Leesutthiphonchai W, Ah-Fong AMV, Judelson HS. Defining Transgene Insertion Sites and Off-Target Effects of Homology-Based Gene Silencing Informs the Application of Functional Genomics Tools in Phytophthora infestans. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2019; 32:915-927. [PMID: 30811313 DOI: 10.1094/mpmi-09-18-0265-ta] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
DNA transformation and homology-based transcriptional silencing are frequently used to assess gene function in Phytophthora spp. Since unplanned side-effects of these tools are not well-characterized, we used P. infestans to study plasmid integration sites and whether knockdowns caused by homology-dependent silencing spread to other genes. Insertions occurred both in gene-dense and gene-sparse regions but disproportionately near the 5' ends of genes, which disrupted native coding sequences. Microhomology at the recombination site between plasmid and chromosome was common. Studies of transformants silenced for 12 different gene targets indicated that neighbors within 500 nt were often cosilenced, regardless of whether hairpin or sense constructs were employed and the direction of transcription of the target. However, this cis spreading of silencing did not occur in all transformants obtained with the same plasmid. Genome-wide studies indicated that unlinked genes with partial complementarity with the silencing-inducing transgene were not usually down-regulated. We learned that hairpin or sense transgenes were not cosilenced with the target in all transformants, which informs how screens for silencing should be performed. We conclude that transformation and gene silencing can be reliable tools for functional genomics in Phytophthora spp. but must be used carefully, especially by testing for the spread of silencing to genes flanking the target.
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Affiliation(s)
- Andrea L Vu
- Department of Microbiology and Plant Pathology, University of California, Riverside, CA 92521, U.S.A
| | | | - Audrey M V Ah-Fong
- Department of Microbiology and Plant Pathology, University of California, Riverside, CA 92521, U.S.A
| | - Howard S Judelson
- Department of Microbiology and Plant Pathology, University of California, Riverside, CA 92521, U.S.A
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25
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Habibian M, Yahyaee-Anzahaee M, Lucic M, Moroz E, Martín-Pintado N, Di Giovanni LD, Leroux JC, Hall J, González C, Damha MJ. Structural properties and gene-silencing activity of chemically modified DNA-RNA hybrids with parallel orientation. Nucleic Acids Res 2019; 46:1614-1623. [PMID: 29373740 PMCID: PMC5829573 DOI: 10.1093/nar/gky024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 01/12/2018] [Indexed: 01/24/2023] Open
Abstract
We report, herein, a new class of RNAi trigger molecules based on the unconventional parallel hybridization of two oligonucleotide chains. We have prepared and studied several parallel stranded (ps) duplexes, in which the parallel orientation is achieved through incorporation of isoguanine and isocytosine to form reverse Watson-Crick base pairs in ps-DNA:DNA, ps-DNA:RNA, ps-(DNA-2'F-ANA):RNA, and ps-DNA:2'F-RNA duplexes. The formation of these duplexes was confirmed by UV melting experiments, FRET and CD studies. In addition, NMR structural studies were conducted on a ps-DNA:RNA hybrid for the first time. Finally, we provide evidence for the unprecedented finding that ps-DNA:RNA and ps-DNA:2'F-RNA hybrids can engage the RNAi pathway to silence gene expression in vitro.
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Affiliation(s)
- Maryam Habibian
- Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, QC H3A 0B8, Canada
| | - Maryam Yahyaee-Anzahaee
- Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, QC H3A 0B8, Canada
| | - Matije Lucic
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland
| | - Elena Moroz
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland
| | - Nerea Martín-Pintado
- Instituto de Química Física 'Rocasolano', CSIC, Serrano 119, 28006 Madrid, Spain
| | - Logan Dante Di Giovanni
- Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, QC H3A 0B8, Canada
| | - Jean-Christophe Leroux
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland
| | - Jonathan Hall
- Department of Chemistry and Applied Biosciences, Institute of Pharmaceutical Sciences, ETH Zurich, Vladimir-Prelog-Weg 1-5, 8093 Zurich, Switzerland
| | - Carlos González
- Instituto de Química Física 'Rocasolano', CSIC, Serrano 119, 28006 Madrid, Spain
| | - Masad J Damha
- Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, QC H3A 0B8, Canada
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Chernikov IV, Vlassov VV, Chernolovskaya EL. Current Development of siRNA Bioconjugates: From Research to the Clinic. Front Pharmacol 2019; 10:444. [PMID: 31105570 PMCID: PMC6498891 DOI: 10.3389/fphar.2019.00444] [Citation(s) in RCA: 121] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 04/08/2019] [Indexed: 12/12/2022] Open
Abstract
Small interfering RNAs (siRNAs) acting via RNA interference mechanisms are able to recognize a homologous mRNA sequence in the cell and induce its degradation. The main problems in the development of siRNA-based drugs for therapeutic use are the low efficiency of siRNA delivery to target cells and the degradation of siRNAs by nucleases in biological fluids. Various approaches have been proposed to solve the problem of siRNA delivery in vivo (e.g., viruses, cationic lipids, polymers, nanoparticles), but all have limitations for therapeutic use. One of the most promising approaches to solve the problem of siRNA delivery to target cells is bioconjugation; i.e., the covalent connection of siRNAs with biogenic molecules (lipophilic molecules, antibodies, aptamers, ligands, peptides, or polymers). Bioconjugates are "ideal nanoparticles" since they do not need a positive charge to form complexes, are less toxic, and are less effectively recognized by components of the immune system because of their small size. This review is focused on strategies and principles for constructing siRNA bioconjugates for in vivo use.
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Affiliation(s)
- Ivan V Chernikov
- Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Valentin V Vlassov
- Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
| | - Elena L Chernolovskaya
- Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine, Siberian Branch of the Russian Academy of Sciences, Novosibirsk, Russia
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27
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Taniguchi H, Suzuki Y, Natori Y. The Evolving Landscape of Cancer Stem Cells and Ways to Overcome Cancer Heterogeneity. Cancers (Basel) 2019; 11:cancers11040532. [PMID: 31013960 PMCID: PMC6520864 DOI: 10.3390/cancers11040532] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 04/02/2019] [Accepted: 04/04/2019] [Indexed: 12/18/2022] Open
Abstract
Cancer stem cells (CSCs) with therapeutic resistance and plasticity can be found in various types of tumors and are recognized as attractive targets for treatments. As CSCs are derived from tissue stem or progenitor cells, and/or dedifferentiated mature cells, their signal transduction pathways are critical in the regulation of CSCs; chronic inflammation causes the accumulation of genetic mutations and aberrant epigenetic changes in these cells, potentially leading to the production of CSCs. However, the nature of CSCs appears to be stronger than the treatments of the past. To improve the treatments targeting CSCs, it is important to inhibit several molecules on the signaling cascades in CSCs simultaneously, and to overcome cancer heterogeneity caused by the plasticity. To select suitable target molecules for CSCs, we have to explore the landscape of CSCs from the perspective of cancer stemness and signaling systems, based on the curated databases of cancer-related genes. We have been studying the integration of a broad range of knowledge and experiences from cancer biology, and also from other interdisciplinary basic sciences. In this review, we have introduced the concept of developing novel strategies targeting CSCs.
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Affiliation(s)
- Hiroaki Taniguchi
- The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-0071, Japan.
- Clinical and Translational Research Center Keio University Hospital, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
| | - Yasunori Suzuki
- Clinical and Translational Research Center Keio University Hospital, 35 Shinanomachi, Shinjuku-ku, Tokyo 160-8582, Japan.
| | - Yukikazu Natori
- BioThinkTank Co. Ltd. 4-10-1-E1706 Minatomirai, Nishi-ku Yokohama, Kanagawa 220-0012, Japan.
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28
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Abstract
RNA interference (RNAi) is the biological process of mRNA degradation induced by complementary sequences double-stranded (ds) small interfering RNAs (siRNA) and suppression of target gene expression. Exogenous siRNAs (perfectly paired dsRNAs of ∼21–25 nt in length) play an important role in host defense against RNA viruses and in transcriptional and post-transcriptional gene regulation in plants and other eukaryotes. Using RNAi technology by transfecting synthetic siRNAs into eukaryotic cells to silence genes has become an indispensable tool to investigate gene functions, and siRNA-based therapy is being developed to knockdown genes implicated in diseases. Other examples of RNAi technology include method of producing highly potent and purified siRNAs directly from Escherichiacoli cells, based on an unexpected discovery that ectopic expression of p19, a plant viral siRNA-binding protein, stabilizes a cryptic siRNA-like RNA species in bacteria. Those siRNAs, named as pro-siRNA for “prokaryotic siRNA”, are bacterial RNase III products that have chemical and functional properties that like eukaryotic siRNAs.
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29
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Chernikov IV, Gladkikh DV, Meschaninova MI, Karelina UA, Ven'yaminova AG, Zenkova MA, Vlassov VV, Chernolovskaya EL. Fluorophore Labeling Affects the Cellular Accumulation and Gene Silencing Activity of Cholesterol-Modified siRNAs In Vitro. Nucleic Acid Ther 2018; 29:33-43. [PMID: 30562146 DOI: 10.1089/nat.2018.0745] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The objective of this study was to analyze the effects of fluorophores on the intracellular accumulation and biological activity of small interfering RNA (siRNA) and its cholesterol conjugates. In this study, we used stem-loop real-time PCR and calibration curves to quantitate cellular siRNA accumulation. Attachment of fluorophores significantly affected both the accumulation and biological activity of siRNA conjugates. The severity of this effect depended significantly on the structure of the conjugate; fluorophores (Cy5.5 or Alexa-488) attached to siRNA, facing the side of the duplex opposite to cholesterol, enhanced the unproductive intracellular accumulation of the conjugate when delivered in carrier-free mode. Enhanced cellular accumulation of siRNA conjugates did not result in enhanced biological activity of the conjugate. Moreover, the attachment of a hydrophobic fluorophore, such as Cy5.5, to conventional siRNA also enhanced its apparent intracellular accumulation, but not its biological activity. Thus, the use of fluorescent labels for the study of the intracellular accumulation of siRNA and its conjugates formed with different molecules is possible only for a limited range of structures, and requires verification using alternative methods.
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Affiliation(s)
- Ivan V Chernikov
- 1 Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Daniil V Gladkikh
- 1 Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Mariya I Meschaninova
- 2 Laboratory of RNA Chemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Ulyana A Karelina
- 1 Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Alya G Ven'yaminova
- 2 Laboratory of RNA Chemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Marina A Zenkova
- 1 Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Valentin V Vlassov
- 1 Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
| | - Elena L Chernolovskaya
- 1 Laboratory of Nucleic Acids Biochemistry, Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk, Russia
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Kartje ZJ, Barkau CL, Rohilla KJ, Ageely EA, Gagnon KT. Chimeric Guides Probe and Enhance Cas9 Biochemical Activity. Biochemistry 2018; 57:3027-3031. [PMID: 29746102 DOI: 10.1021/acs.biochem.8b00107] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
DNA substitutions in RNA can probe the importance of A-form structure, 2'-hydroxyl contacts, and conformational constraints within RNA-guided enzymes. Using this approach, we found that Cas9 biochemical activity tolerated significant substitution with DNA nucleotides in the clustered regularly interspaced short palindromic repeat RNA (crRNA). Only minimal RNA content was needed in or near the seed region. Simultaneous substitution at all positions with predicted crRNA-Cas9 2'-hydroxyl contacts had no effect on enzyme activity. The trans-activating crRNA (tracrRNA) also tolerated >50% substitution with DNA. DNA substitutions in the tracrRNA-pairing region of crRNA consistently enhanced cleavage activity while maintaining or improving target specificity. Together, results point to a prominent role for guide:target A-form-like helical structure and a possible regulatory role for the crRNA-tracrRNA pairing motif. A model chimeric crRNA with high activity did not significantly alter RNP assembly or target binding but did reduce Cas9 ribonucleoprotein stability, suggesting effects through conformation or dynamics. Cas9 directed by chimeric RNA-DNA guides may represent a cost-effective synthetic or molecular biology tool for robust and specific DNA cleavage.
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Affiliation(s)
- Zachary J Kartje
- Department of Chemistry and Biochemistry , Southern Illinois University , Carbondale , Illinois 62901 , United States
| | - Christopher L Barkau
- Department of Biochemistry and Molecular Biology, School of Medicine , Southern Illinois University , Carbondale , Illinois 62901 , United States
| | - Kushal J Rohilla
- Department of Biochemistry and Molecular Biology, School of Medicine , Southern Illinois University , Carbondale , Illinois 62901 , United States
| | - Eman A Ageely
- Department of Chemistry and Biochemistry , Southern Illinois University , Carbondale , Illinois 62901 , United States
| | - Keith T Gagnon
- Department of Chemistry and Biochemistry , Southern Illinois University , Carbondale , Illinois 62901 , United States
- Department of Biochemistry and Molecular Biology, School of Medicine , Southern Illinois University , Carbondale , Illinois 62901 , United States
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31
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Taniguchi H, Hoshino D, Moriya C, Zembutsu H, Nishiyama N, Yamamoto H, Kataoka K, Imai K. Silencing PRDM14 expression by an innovative RNAi therapy inhibits stemness, tumorigenicity, and metastasis of breast cancer. Oncotarget 2018; 8:46856-46874. [PMID: 28423353 PMCID: PMC5564528 DOI: 10.18632/oncotarget.16776] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2016] [Accepted: 03/22/2017] [Indexed: 12/11/2022] Open
Abstract
PR domain zinc finger protein 14 (PRDM14) maintains stemness in embryonic stem cells via epigenetic mechanisms. Although PRDM14 is elevated in several cancers, it is unclear if and how PRDM14 confers stem cell-like properties and epigenetic changes to cancer cells. Here, we examined the phenotypic characteristics and epigenetic and gene expression profiles of cancer cells that differentially express PRDM14, and assessed the potential of PRDM14-targeted cancer therapy. PRDM14 expression was markedly increased in many different cancer types and correlated with poor survival of breast cancer patients. PRDM14 conferred stem cell-like phenotypes to cancer cells and regulated the expression of genes involved in cancer stemness, metastasis, and chemoresistance. PRDM14 also reduced the methylation of proto-oncogene and stemness gene promoters and PRDM14-binding regions were primarily occupied by histone H3 Lys-4 trimethylation (H3K4me3), both of which are positively correlated with gene expression. Moreover, strong PRDM14 binding sites coincided with promoters containing both H3K4me3 and H3K27me3 histone marks. Using calcium phosphate hybrid micelles as an RNAi delivery system, silencing of PRDM14 expression by chimera RNAi reduced tumor size and metastasis in vivo without causing adverse effects. Conditional loss of PRDM14 function also improved survival of MMTV-Wnt-1 transgenic mice, a spontaneous model of murine breast cancer. Our findings suggest that PRDM14 inhibition may be an effective and novel therapy for cancer stem cells.
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Affiliation(s)
- Hiroaki Taniguchi
- The Center for Antibody and Vaccine Therapy, Research Hospital, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| | - Daisuke Hoshino
- Cancer Biology Department, The Kanagawa Cancer Center Research Institute, Kanagawa 241-0815, Japan
| | - Chiharu Moriya
- The Center for Antibody and Vaccine Therapy, Research Hospital, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
| | - Hitoshi Zembutsu
- Division of Genetics, National Cancer Center Research Institute, Tokyo 104-0045, Japan
| | - Nobuhiro Nishiyama
- Polymer Chemistry Division, Chemical Resources Laboratory, Tokyo Institute of Technology, Kanagawa 226-8503, Japan
| | - Hiroyuki Yamamoto
- Department of Gastroenterology and Hepatology, School of Medicine, St. Marianna Medical University, Kanagawa 216-0015, Japan
| | - Kazunori Kataoka
- Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Kohzoh Imai
- The Center for Antibody and Vaccine Therapy, Research Hospital, The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan.,The Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
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32
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Nikam RR, Gore KR. Journey of siRNA: Clinical Developments and Targeted Delivery. Nucleic Acid Ther 2018; 28:209-224. [PMID: 29584585 DOI: 10.1089/nat.2017.0715] [Citation(s) in RCA: 100] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Since the evolutionary discovery of RNA interference and its utilization for gene knockdown in mammalian cell, a remarkable progress has been achieved in small interfering RNA (siRNA) therapeutics. siRNA is a promising tool, utilized as therapeutic agent against various diseases. Despite its significant potential benefits, safe, efficient, and target oriented delivery of siRNA is one of the major challenges in siRNA therapeutics. This review covers major achievements in clinical trials and targeted delivery of siRNAs using various targeting ligand-receptor pair. Local and systemically administered siRNA drug candidates at various phases in clinical trials are described in this review. This review also provides a deep insight in development of targeted delivery of siRNA. Various targeting ligand-siRNA pair with complexation and conjugation approaches are discussed in this review. This will help to achieve further optimization and development in targeted delivery of siRNAs to achieve higher gene silencing efficiency with lowest siRNA dose availability.
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Affiliation(s)
| | - Kiran R Gore
- Department of Chemistry, University of Mumbai , Mumbai, India
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33
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Suter SR, Ball-Jones A, Mumbleau MM, Valenzuela R, Ibarra-Soza J, Owens H, Fisher AJ, Beal PA. Controlling miRNA-like off-target effects of an siRNA with nucleobase modifications. Org Biomol Chem 2018; 15:10029-10036. [PMID: 29164215 DOI: 10.1039/c7ob02654d] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
SiRNAs can cause unintended gene silencing due to miRNA-like effects because of the similarity in function of an siRNA guide strand and a miRNA. Here we evaluate the effect on miRNA-like off targeting of introducing the adenosine derivative 7-EAA and triazoles prepared from 7-EAA at different positions in an siRNA guide strand. We find that a sterically demanding triazole placed in the RNA duplex major groove at position six of the guide strand dramatically reduces miRNA-like off targeting potency. A high-resolution structure of an RNA duplex bearing a novel, major-groove localized triazole is reported, which suggests that modified triazoles could be disrupting the hAgo2-guide-target RNA ternary complex. Five different triazole modifications were tested at the guide strand 6-position for effects on on-target and miRNA-like off target knockdown potency. A 7-EAA triazole bearing a benzylamine substituent displayed on-target knockdown activity as potent as the native siRNA, while having an IC50 against a miRNA-like off target >100-fold higher. Melting temperature studies revealed no obvious correlation between potency in knockdown assays and a modification's effect on duplex stability. These results, along with known structures of hAgo2-guide-target ternary complexes, are used to rationalize the effect of 7-EAA triazoles on miRNA-like off target effects.
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Affiliation(s)
- Scott R Suter
- Department of Chemistry, University of California, Davis, One Shields Ave, Davis, California, 95616 USA.
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34
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Seok H, Lee H, Jang ES, Chi SW. Evaluation and control of miRNA-like off-target repression for RNA interference. Cell Mol Life Sci 2018; 75:797-814. [PMID: 28905147 PMCID: PMC11105550 DOI: 10.1007/s00018-017-2656-0] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 09/06/2017] [Accepted: 09/07/2017] [Indexed: 01/08/2023]
Abstract
RNA interference (RNAi) has been widely adopted to repress specific gene expression and is easily achieved by designing small interfering RNAs (siRNAs) with perfect sequence complementarity to the intended target mRNAs. Although siRNAs direct Argonaute (Ago), a core component of the RNA-induced silencing complex (RISC), to recognize and silence target mRNAs, they also inevitably function as microRNAs (miRNAs) and suppress hundreds of off-targets. Such miRNA-like off-target repression is potentially detrimental, resulting in unwanted toxicity and phenotypes. Despite early recognition of the severity of miRNA-like off-target repression, this effect has often been overlooked because of difficulties in recognizing and avoiding off-targets. However, recent advances in genome-wide methods and knowledge of Ago-miRNA target interactions have set the stage for properly evaluating and controlling miRNA-like off-target repression. Here, we describe the intrinsic problems of miRNA-like off-target effects caused by canonical and noncanonical interactions. We particularly focus on various genome-wide approaches and chemical modifications for the evaluation and prevention of off-target repression to facilitate the use of RNAi with secured specificity.
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Affiliation(s)
- Heeyoung Seok
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Korea
| | - Haejeong Lee
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Korea
| | - Eun-Sook Jang
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Korea
- EncodeGEN Co. Ltd, Seoul, 06329, Korea
| | - Sung Wook Chi
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Korea.
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35
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Abstract
Genome editing technologies have been revolutionized by the discovery of prokaryotic RNA-guided defense system called CRISPR-Cas. Cas9, a single effector protein found in type II CRISPR systems, has been at the heart of this genome editing revolution. Nearly half of the Cas9s discovered so far belong to the type II-C subtype but have not been explored extensively. Type II-C CRISPR-Cas systems are the simplest of the type II systems, employing only three Cas proteins. Cas9s are central players in type II-C systems since they function in multiple steps of the CRISPR pathway, including adaptation and interference. Type II-C CRISPR systems are found in bacteria and archaea from very diverse environments, resulting in Cas9s with unique and potentially useful properties. Certain type II-C Cas9s possess unusually long PAMs, function in unique conditions (e.g., elevated temperature), and tend to be smaller in size. Here, we review the biology, mechanism, and applications of the type II-C CRISPR systems with particular emphasis on their Cas9s.
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Affiliation(s)
- Aamir Mir
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
| | - Alireza Edraki
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
| | - Jooyoung Lee
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
| | - Erik J. Sontheimer
- RNA Therapeutics Institute, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, MA 01605, U.S.A
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36
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Abstract
PRDI-BF1 and RIZ homology (PR) domain zinc finger protein 14 (PRDM14) contains a PR domain related to the SET methyltransferase domain and zinc finger motifs. PRDM14 maintains stemness in embryonic stem cells and primordial germ cells via epigenetic mechanisms. PRDM14, however, is not expressed in normal differentiated tissues. We and other groups previously reported that PRDM14 expression is markedly higher in some types of cancers compared to the corresponding normal tissues. PRDM14 confers stem cell-like characteristics upon cancer cells, such as sphere formation, dye efflux, chemotherapy resistance, proliferation, and distant metastasis. Cancer stem cells (CSCs) are thought to be responsible for tumor initiation, drug and radiation resistance, invasive growth, metastasis, and tumor relapse, which are the primary causes of cancer-related deaths. Because CSCs are also thought to be resistant to conventional therapies, an effective and novel therapeutic approach for CSCs is imperative.RNAi silencing of PRDM14 expressed by breast and pancreatic cancer cells reduced tumor size and distant metastasis of these cells in nude mice. Inhibition of PRDM14 expression by cancer cells may be an effective and radical therapy for solid cancers. In this chapter, we discuss methods for studying CSC-like properties in cancer cells and describe the use of siRNA with a drug delivery system by systemic injection in vivo.
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Affiliation(s)
- Hiroaki Taniguchi
- The Center for Antibody and Vaccine Therapy, Research Hospital, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan.
| | - Kohzoh Imai
- The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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37
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Mutisya D, Hardcastle T, Cheruiyot SK, Pallan PS, Kennedy SD, Egli M, Kelley ML, Smith AVB, Rozners E. Amide linkages mimic phosphates in RNA interactions with proteins and are well tolerated in the guide strand of short interfering RNAs. Nucleic Acids Res 2017; 45:8142-8155. [PMID: 28854734 PMCID: PMC5737567 DOI: 10.1093/nar/gkx558] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 06/18/2017] [Indexed: 12/21/2022] Open
Abstract
While the use of RNA interference (RNAi) in molecular biology and functional genomics is a well-established technology, in vivo applications of synthetic short interfering RNAs (siRNAs) require chemical modifications. We recently found that amides as non-ionic replacements for phosphodiesters may be useful modifications for optimization of siRNAs. Herein, we report a comprehensive study of systematic replacement of a single phosphate with an amide linkage throughout the guide strand of siRNAs. The results show that amides are surprisingly well tolerated in the seed and central regions of the guide strand and increase the silencing activity when placed between nucleosides 10 and 12, at the catalytic site of Argonaute. A potential explanation is provided by the first crystal structure of an amide-modified RNA-DNA with Bacillus halodurans RNase H1. The structure reveals how small changes in both RNA and protein conformation allow the amide to establish hydrogen bonding interactions with the protein. Molecular dynamics simulations suggest that these alternative binding modes may compensate for interactions lost due to the absence of a phosphodiester moiety. Our results suggest that an amide can mimic important hydrogen bonding interactions with proteins required for RNAi activity and may be a promising modification for optimization of biological properties of siRNAs.
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Affiliation(s)
- Daniel Mutisya
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, NY 13902, USA
| | | | - Samwel K Cheruiyot
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, NY 13902, USA
| | - Pradeep S Pallan
- Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, TN 37232, USA
| | - Scott D Kennedy
- Department of Biochemistry and Biophysics, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
| | - Martin Egli
- Department of Biochemistry, School of Medicine, Vanderbilt University, Nashville, TN 37232, USA
| | | | | | - Eriks Rozners
- Department of Chemistry, Binghamton University, The State University of New York, Binghamton, NY 13902, USA
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38
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Moriya C, Taniguchi H, Miyata K, Nishiyama N, Kataoka K, Imai K. Inhibition of PRDM14 expression in pancreatic cancer suppresses cancer stem-like properties and liver metastasis in mice. Carcinogenesis 2017; 38:638-648. [PMID: 28498896 DOI: 10.1093/carcin/bgx040] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 05/04/2017] [Indexed: 01/04/2023] Open
Abstract
Pancreatic cancer is one of the most lethal types of cancer, with aggressive properties characterized by metastasis, recurrence and drug resistance. Cancer stem cells are considered to be responsible for these properties. PRDM14, a transcriptional regulator that maintains pluripotency in embryonic stem cells, is overexpressed in some cancers. Here, we assessed PRDM14 expression and the effects of PRDM14 knockdown on cancer stem-like phenotypes in pancreatic cancer. We observed that PRDM14 protein was overexpressed in pancreatic cancer tissues compared with normal pancreatic tissues. Using lentiviral shRNA-transduced pancreatic cancer cells, we found that PRDM14 knockdown decreased sphere formation, number of side population and cell surface marker-positive cells and subcutaneous xenograft tumors and liver metastasis in mice. This was accompanied by upregulation of some microRNAs (miRNAs), including miR-125a-3p. miR-125a-3p, a tumor suppressor that is down-regulated in pancreatic cancer, has been suggested to regulate the expression of the Src-family kinase, Fyn. In PRDM14-knockdown cells, Fyn was expressed at lower levels and downstream proteins were less activated. These changes were considered to cause suppression of the above cancer phenotypes. In addition, we used small interfering RNA (siRNA)-based therapy targeting PRDM14 in a mouse model of liver metastasis induced using MIA-PaCa2 cells, and this treatment significantly decreased metastasis and in vitro migration. Taken together, these results suggest that targeting the overexpression of PRDM14 suppresses cancer stem-like phenotypes, including liver metastasis, via miRNA regulation and siRNA-based therapy targeting it shows promise as a treatment for patients with pancreatic cancer.
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Affiliation(s)
| | | | - Kanjiro Miyata
- Center for Antibody and Vaccine Therapy, Research Hospital, Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan, Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Nobuhiro Nishiyama
- Polymer Chemistry Division, Chemical Resources Laboratory, Tokyo Institute of Technology, Yokohama 226-8503, Japan and
| | - Kazunori Kataoka
- Center for Antibody and Vaccine Therapy, Research Hospital, Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan, Department of Materials Engineering, Graduate School of Engineering, The University of Tokyo, Tokyo 113-8656, Japan
| | - Kohzoh Imai
- Institute of Medical Science, The University of Tokyo, Tokyo 108-8639, Japan
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39
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Iribe H, Miyamoto K, Takahashi T, Kobayashi Y, Leo J, Aida M, Ui-Tei K. Chemical Modification of the siRNA Seed Region Suppresses Off-Target Effects by Steric Hindrance to Base-Pairing with Targets. ACS OMEGA 2017; 2:2055-2064. [PMID: 29450406 PMCID: PMC5808362 DOI: 10.1021/acsomega.7b00291] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2017] [Accepted: 05/05/2017] [Indexed: 05/12/2023]
Abstract
Chemical modifications of 2'-O-methyl (2'-OMe) and locked nucleic acid (LNA) of the nucleotides in the seed region (positions 2-8) of the small interfering RNA (siRNA) guide strand significantly reduced seed-matched (SM) off-target effects. The siRNA with 2'-OMe modifications inhibited the expression of a completely-matched (CM) target gene, whereas that with LNA modifications did not inhibit the expression of the CM target. By computational predictions of conformational changes of siRNA by these modifications, we revealed that both modifications in the siRNA seed region reduce SM off-target effects by steric hindrance to base-pairing with target transcripts but LNA modifications also disturb the association of the siRNA guide strand with the Argonaute (AGO) protein by altering RNA conformation. Thus, chemical modifications of the siRNA guide strand, which alter steric conformation to disturb base-pairing with target transcripts but do not disturb the association with the AGO protein, may successfully suppress off-target effects without substantial loss of RNA silencing activity.
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Affiliation(s)
- Hanna Iribe
- Department
of Computational Biology and Medical Science, Graduate School of Frontier
Sciences, The University of Tokyo, Chiba 277-8581, Japan
| | - Kengo Miyamoto
- Center
for Quantum Life Sciences and Department of Chemistry, Graduate School
of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Tomoko Takahashi
- Department
of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Yoshiaki Kobayashi
- Department
of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
| | - Jastina Leo
- Department
of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
- Faculty
of Microbiology, Immunology and Molecular Genetics, University of California, Los
Angeles, California 90095, United States
| | - Misako Aida
- Center
for Quantum Life Sciences and Department of Chemistry, Graduate School
of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Kumiko Ui-Tei
- Department
of Computational Biology and Medical Science, Graduate School of Frontier
Sciences, The University of Tokyo, Chiba 277-8581, Japan
- Department
of Biological Sciences, Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan
- E-mail:
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40
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Bisaria N, Jarmoskaite I, Herschlag D. Lessons from Enzyme Kinetics Reveal Specificity Principles for RNA-Guided Nucleases in RNA Interference and CRISPR-Based Genome Editing. Cell Syst 2017; 4:21-29. [PMID: 28125791 PMCID: PMC5308874 DOI: 10.1016/j.cels.2016.12.010] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 09/15/2016] [Accepted: 12/09/2016] [Indexed: 12/26/2022]
Abstract
RNA-guided nucleases (RGNs) provide sequence-specific gene regulation through base-pairing interactions between a small RNA guide and target RNA or DNA. RGN systems, which include CRISPR-Cas9 and RNA interference (RNAi), hold tremendous promise as programmable tools for engineering and therapeutic purposes. However, pervasive targeting of sequences that closely resemble the intended target has remained a major challenge, limiting the reliability and interpretation of RGN activity and the range of possible applications. Efforts to reduce off-target activity and enhance RGN specificity have led to a collection of empirically derived rules, which often paradoxically include decreased binding affinity of the RNA-guided nuclease to its target. We consider the kinetics of these reactions and show that basic kinetic properties can explain the specificities observed in the literature and the changes in these specificities in engineered systems. The kinetic models described provide a foundation for understanding RGN targeting and a necessary conceptual framework for their rational engineering.
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Affiliation(s)
- Namita Bisaria
- Department of Biochemistry, Stanford University, Stanford, CA 94305, USA
| | - Inga Jarmoskaite
- Department of Biochemistry, Stanford University, Stanford, CA 94305, USA
| | - Daniel Herschlag
- Department of Biochemistry, Stanford University, Stanford, CA 94305, USA; Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA; Department of Chemistry, Stanford University, Stanford, CA 94305, USA; Stanford ChEM-H, Stanford University, Stanford, CA 94305, USA.
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41
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Chemical and structural modifications of RNAi therapeutics. Adv Drug Deliv Rev 2016; 104:16-28. [PMID: 26549145 DOI: 10.1016/j.addr.2015.10.015] [Citation(s) in RCA: 92] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Revised: 10/14/2015] [Accepted: 10/23/2015] [Indexed: 12/25/2022]
Abstract
Small interfering RNA (siRNA), a 21-23nt double-stranded RNA responsible for post-transcriptional gene silencing, has attracted great interests as promising genomic drugs, due to its strong ability to silence target genes in a sequence-specific manner. Despite high silencing efficiency and on-target specificity, the clinical translation of siRNA has been hindered by its inherent features: poor intracellular delivery, limited blood stability, unpredictable immune responses and unwanted off-targeting effects. To overcome these hindrances, researchers have made various advances to modify siRNA itself and to improve its delivery. In this review paper, first we briefly discuss the innate properties and delivery barriers of siRNA. Then, we describe recent progress in (1) chemically and structurally modified siRNAs to solve their intrinsic problems and (2) siRNA delivery formulations including siRNA conjugates, polymerized siRNA, and nucleic acid-based nanoparticles to improve in vivo delivery.
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42
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Alagia A, Eritja R. siRNA and RNAi optimization. WILEY INTERDISCIPLINARY REVIEWS-RNA 2016; 7:316-29. [PMID: 26840434 DOI: 10.1002/wrna.1337] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 12/17/2015] [Accepted: 12/18/2015] [Indexed: 12/12/2022]
Abstract
The discovery and examination of the posttranscriptional gene regulatory mechanism known as RNA interference (RNAi) contributed to the identification of small interfering RNA (siRNA) and the comprehension of its enormous potential for clinical purposes. Theoretically, the ability of specific target gene downregulation makes the RNAi pathway an appealing solution for several diseases. Despite numerous hurdles resulting from the inherent properties of siRNA molecule and proper delivery to the target tissue, more than 50 RNA-based drugs are currently under clinical testing. In this work, we analyze the recent literature in the optimization of siRNA molecules. In detail, we focused on describing the most recent advances of siRNA field aimed at optimize siRNA pharmacokinetic properties. Special attention has been given in describing the impact of RNA modifications in the potential off-target effects (OTEs) such as saturation of the RNAi machinery, passenger strand-mediated silencing, immunostimulation, and miRNA-like OTEs as well as to recent developments on the delivery issue. The novel delivery systems and modified siRNA provide significant steps toward the development of reliable siRNA molecules for therapeutic use. WIREs RNA 2016, 7:316-329. doi: 10.1002/wrna.1337 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Adele Alagia
- Chemical and Biomolecular Nanotechnology, CIBER-BBN, Institute for Advanced Chemistry of Catalonia, IQAC-CSIC, Barcelona, Spain
| | - Ramon Eritja
- Chemical and Biomolecular Nanotechnology, CIBER-BBN, Institute for Advanced Chemistry of Catalonia, IQAC-CSIC, Barcelona, Spain
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43
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Roberts TC, Ezzat K, El Andaloussi S, Weinberg MS. Synthetic SiRNA Delivery: Progress and Prospects. Methods Mol Biol 2016; 1364:291-310. [PMID: 26472459 DOI: 10.1007/978-1-4939-3112-5_23] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Small interfering RNA (siRNA) is a powerful tool for modulating gene expression by RNA interference (RNAi). Duplex RNA oligonucleotides induce cleavage of homologous target transcripts, thereby enabling posttranscriptional silencing of potentially any gene. As such, siRNAs may have utility as novel pharmaceuticals for a wide range of diseases. However, a lack of "drug-likeness," physiological barriers, and potential toxicities have meant that systemic delivery of SiRNAs in vivo remains a major challenge. Here we discuss various strategies that have been employed to solve the problem of SiRNA delivery. These include chemical modification of the SiRNA, direct conjugation to bioactive moieties, and nanoparticle formulations.
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Affiliation(s)
- Thomas C Roberts
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA, 92037, USA
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, OX1 3QX, UK
- Development, Aging and Regeneration Program, Sanford Burnham Prebys Medical Discovery Institute, 10901 N. Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Kariem Ezzat
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, OX1 3QX, UK
| | - Samir El Andaloussi
- Department of Physiology, Anatomy and Genetics, University of Oxford, South Parks Road, Oxford, OX1 3QX, UK
- Department of Laboratory Medicine, Karolinska Institutet, Huddinge, Sweden
| | - Marc S Weinberg
- Department of Molecular and Experimental Medicine, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA, 92037, USA.
- Antiviral Gene Therapy Research Unit, Department of Molecular Medicine and Haematology, University of the Witwatersrand Medical School, Johannesburg, WITS 2050, South Africa.
- HIV Pathogenesis Research Unit, Department of Molecular Medicine and Haematology, University of the Witwatersrand Medical School, Johannesburg, WITS 2050, South Africa.
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44
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Lee HS, Seok H, Lee DH, Ham J, Lee W, Youm EM, Yoo JS, Lee YS, Jang ES, Chi SW. Abasic pivot substitution harnesses target specificity of RNA interference. Nat Commun 2015; 6:10154. [PMID: 26679372 PMCID: PMC4703836 DOI: 10.1038/ncomms10154] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Accepted: 11/08/2015] [Indexed: 01/06/2023] Open
Abstract
Gene silencing via RNA interference inadvertently represses hundreds of off-target transcripts. Because small interfering RNAs (siRNAs) can function as microRNAs, avoiding miRNA-like off-target repression is a major challenge. Functional miRNA-target interactions are known to pre-require transitional nucleation, base pairs from position 2 to the pivot (position 6). Here, by substituting nucleotide in pivot with abasic spacers, which prevent base pairing and alleviate steric hindrance, we eliminate miRNA-like off-target repression while preserving on-target activity at ∼ 80-100%. Specifically, miR-124 containing dSpacer pivot substitution (6pi) loses seed-mediated transcriptome-wide target interactions, repression activity and biological function, whereas other conventional modifications are ineffective. Application of 6pi allows PCSK9 siRNA to efficiently lower plasma cholesterol concentration in vivo, and abolish potentially deleterious off-target phenotypes. The smallest spacer, C3, also shows the same improvement in target specificity. Abasic pivot substitution serves as a general means to harness the specificity of siRNA experiments and therapeutic applications.
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Affiliation(s)
- Hye-Sook Lee
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
| | - Heeyoung Seok
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
| | - Dong Ha Lee
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710, Korea
| | - Juyoung Ham
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710, Korea
| | - Wooje Lee
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea
| | - Emilia Moonkyung Youm
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710, Korea
| | - Jin Seon Yoo
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710, Korea
| | | | - Eun-Sook Jang
- Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710, Korea.,EncodeGEN Co. Ltd., Seoul 135-994, Korea
| | - Sung Wook Chi
- Division of Life Sciences, College of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea.,Department of Health Sciences and Technology, Samsung Advanced Institute for Health Sciences and Technology, Sungkyunkwan University, Seoul 135-710, Korea.,Samsung Research Institute for Future Medicine, Samsung Medical Center, Seoul 135-710, Korea
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45
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Luan C, Yang Z, Chen B. The functional role of microRNA in acute lymphoblastic leukemia: relevance for diagnosis, differential diagnosis, prognosis, and therapy. Onco Targets Ther 2015; 8:2903-14. [PMID: 26508875 PMCID: PMC4610789 DOI: 10.2147/ott.s92470] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
MicroRNAs (miRNAs), a new class of noncoding RNAs, which can hybridize to target messenger RNAs and regulate their expression posttranscriptionally, express differentially in distinct stages of lymphopoiesis and influence the direction of lymphoid precursor maturation. Hence, there is aberrant expression of miRNAs involved in malignant lymphopoiesis, and these aberrations can be used as signatures of acute lymphoblastic leukemia (ALL) with different subtypes. In addition, changes in the expression of several miRNAs may have functional relevance with leukemogenesis or drug resistance. As a result, the reversal of the expression of these miRNAs may alleviate the disease to some extent and improve clinical outcomes. However, among the studies of miRNAs, there are still some problems that need to be solved to understand the function of miRNAs in ALL more thoroughly.
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Affiliation(s)
- Chengxin Luan
- Department of Hematology and Oncology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, People's Republic of China
| | - Zixue Yang
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, People's Republic of China
| | - Baoan Chen
- Department of Hematology and Oncology, Zhongda Hospital, School of Medicine, Southeast University, Nanjing, People's Republic of China
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46
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Abstract
The efficient delivery of short interfering RNA (siRNA) is an enormous challenge in the field of gene therapy. Herein, we report a delivery nanosystem based on programmed DNA self-assembly mammalian target of rapamycin (mTOR) siRNA-loaded DNA nanotubes (DNA-NTs). We demonstrate that these siRNA-DNA-NTs can be effectively transfected into pulmonary arterial smooth muscle cells (PASMCs) via endocytosis; and that the loaded mTOR siRNA can induce obvious autophagy and inhibit cell growth under both normal and hypoxic conditions. Moreover, we found that mTOR siRNA can control the autophagy and proliferation of PASMCs under hypoxic condition, suggesting a potential therapeutic application for mTOR siRNA in diseases involving abnormal autophagy in PASMCs.
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47
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Ozcan G, Ozpolat B, Coleman RL, Sood AK, Lopez-Berestein G. Preclinical and clinical development of siRNA-based therapeutics. Adv Drug Deliv Rev 2015; 87:108-19. [PMID: 25666164 DOI: 10.1016/j.addr.2015.01.007] [Citation(s) in RCA: 330] [Impact Index Per Article: 36.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 01/23/2015] [Accepted: 01/29/2015] [Indexed: 12/23/2022]
Abstract
The discovery of RNA interference, first in plants and Caenorhabditis elegans and later in mammalian cells, led to the emergence of a transformative view in biomedical research. Knowledge of the multiple actions of non-coding RNAs has truly allowed viewing DNA, RNA and proteins in novel ways. Small interfering RNAs (siRNAs) can be used as tools to study single gene function both in vitro and in vivo and are an attractive new class of therapeutics, especially against undruggable targets for the treatment of cancer and other diseases. Despite the potential of siRNAs in cancer therapy, many challenges remain, including rapid degradation, poor cellular uptake and off-target effects. Rational design strategies, selection algorithms, chemical modifications and nanocarriers offer significant opportunities to overcome these challenges. Here, we review the development of siRNAs as therapeutic agents from early design to clinical trial, with special emphasis on the development of EphA2-targeting siRNAs for ovarian cancer treatment.
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48
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Ballarín-González B, Thomsen TB, Howard KA. Clinical translation of RNAi-based treatments for respiratory diseases. Drug Deliv Transl Res 2015; 3:84-99. [PMID: 25787868 PMCID: PMC7097609 DOI: 10.1007/s13346-012-0098-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The ability to harness the RNA interference (RNAi) mechanism as a potential potent therapeutic has attracted great interest from academia and industry. Numerous preclinical and recent clinical trials have demonstrated the effectiveness of RNAi triggers such as synthetic small interfering RNA (siRNA). Chemical modification and delivery technologies can be utilized to avoid immune stimulation and improve the bioactivity and pharmacokinetics. Local application to the respiratory epithelia allows direct access to the site of respiratory pathogens that include influenza and respiratory syncytial virus (RSV). This review outlines the essential steps required for the clinical translation of RNAi-based respiratory therapies including disease and RNA target selection, siRNA design, respiratory barriers, and delivery solutions. Attention is given to antiviral therapies and preclinical evaluation with focus on the current status of anti-RSV clinical trials.
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Affiliation(s)
- Borja Ballarín-González
- Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology and Genetics, University of Aarhus, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
| | - Troels Bo Thomsen
- Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology and Genetics, University of Aarhus, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
| | - Kenneth Alan Howard
- Interdisciplinary Nanoscience Center (iNANO), Department of Molecular Biology and Genetics, University of Aarhus, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
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49
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Smalheiser NR, Gomes OLA. Mammalian Argonaute-DNA binding? Biol Direct 2014; 10:27. [PMID: 25472905 PMCID: PMC4258305 DOI: 10.1186/s13062-014-0027-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Accepted: 11/19/2014] [Indexed: 12/21/2022] Open
Abstract
When a field shares the consensus that a particular phenomenon does NOT occur, this may reflect extensive experimental investigations with negative outcomes, or may represent the “common sense” position based on current knowledge and established ways of thinking. The current consensus of the RNA field is that eukaryotic Argonaute (Ago) proteins employ RNA guides and target other RNAs. The alternative -- that eukaryotic Ago has biologically important interactions with DNA in vivo – has not been seriously considered, in part because the only role contemplated for DNA was as a guide strand, and in part because it did not seem plausible that any natural source of suitable DNAs exists in eukaryotic cells. However, eukaryotic Argonaute domains bind DNA in the test tube, and several articles report that small inhibitory double-stranded DNAs do have the ability to silence target RNAs in a sequence-dependent (though poorly characterized) manner. A search of the literature identified potential DNA binding partners for Ago, including (among others) single-stranded DNAs residing in extracellular vesicles, and cytoplasmic satellite-repeat DNA fragments that are associated with the plasma membrane and transcribed by Pol II. It is interesting to note that both cytoplasmic and extracellular vesicle DNA are expressed at greatly elevated levels in cancer cells relative to normal cells. In such a pathological scenario, if not under normal conditions, there may be appreciable binding of Ago to DNA despite its lower affinity compared to RNA. If so, DNA might displace Ago from binding to its normal partners (miRNAs, siRNAs and other short ncRNAs), disrupting tightly controlled post-transcriptional gene silencing processes that are vital to correct functioning of a normal cell. The possible contribution to cancer pathogenesis is a strong motivator for further investigation of Ago-DNA binding. More generally, this case underscores the need for better informatics tools to allow investigators to analyze the state of a given scientific question at a high-level and to identify possible new research directions. Reviewers: This article was reviewed by Eugene Koonin, Kira S. Makarova, Alexander Maxwell Burroughs (nominated by L Aravind), and Isidore Rigoutsos. Open peer review: Reviewed by Eugene Koonin, Kira S. Makarova, Alexander Maxwell Burroughs (nominated by L Aravind), and Isidore Rigoutsos. For the full reviews, please go to the Reviewers’ comments section.
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50
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Hirose M, Yamato K, Endo S, Saito R, Ueno T, Hirai S, Suzuki H, Abei M, Natori Y, Hyodo I. MDM4 expression as an indicator of TP53 reactivation by combined targeting of MDM2 and MDM4 in cancer cells without TP53 mutation. Oncoscience 2014; 1:830-43. [PMID: 25621298 PMCID: PMC4303891 DOI: 10.18632/oncoscience.103] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 11/24/2014] [Indexed: 12/17/2022] Open
Abstract
MDM2 and MDM4, a structurally related MDM2 homolog, negatively regulates expression and functions of TP53 tumor suppressor gene. To explore the precise expression patterns and function of MDM2 and MDM4 in wild-type (wt) TP53 cancer cells, we analyzed 11 various cancer cell lines with wt TP53. All cell lines exhibited deregulated expression of MDM2 and MDM4, and were divided into two distinct types; the one expressing high levels of MDM4 and another expressing low levels of MDM4. The low MDM4 type expressed higher MDM2 levels than the high MDM4 type. In cells with high MDM4 expression, knockdown of MDM4 or MDM2 reactivated TP53, and simultaneous knockdown of MDM2 and MDM4 synergistically reactivated TP53. In contrast, in cells with low MDM4 expression, knockdown of only MDM2 reactivated TP53. These results suggest that both MDM2 and MDM4 are closely involved in TP53 inactivation in cancer cells with high MDM4 expression, whereas only MDM2, and not MDM4, is a regulator of TP53 in cells with low MDM4 expression. MDM4 expression in wt TP53-tumors is a potential indicator for TP53 reactivation cancer therapy by simultaneous targeting of MDM4 and MDM2. Specific knockdown of MDM2 and MDM4 might be applicable for TP53 restoration therapy.
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Affiliation(s)
- Mitsuaki Hirose
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Kenji Yamato
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Shinji Endo
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Rie Saito
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Takunori Ueno
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Sachiko Hirai
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Hideo Suzuki
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Masato Abei
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | | | - Ichinosuke Hyodo
- Department of Gastroenterology and Hepatology, Institute of Clinical Medicine, Graduate School of Comprehensive Human Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
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