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Nagasawa R, Onizuka K, Komatsu KR, Miyashita E, Murase H, Ojima K, Ishikawa S, Ozawa M, Saito H, Nagatsugi F. Large-scale analysis of small molecule-RNA interactions using multiplexed RNA structure libraries. Commun Chem 2024; 7:98. [PMID: 38693284 DOI: 10.1038/s42004-024-01181-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 04/17/2024] [Indexed: 05/03/2024] Open
Abstract
The large-scale analysis of small-molecule binding to diverse RNA structures is key to understanding the required interaction properties and selectivity for developing RNA-binding molecules toward RNA-targeted therapies. Here, we report a new system for performing the large-scale analysis of small molecule-RNA interactions using a multiplexed pull-down assay with RNA structure libraries. The system profiled the RNA-binding landscapes of G-clamp and thiazole orange derivatives, which recognizes an unpaired guanine base and are good probes for fluorescent indicator displacement (FID) assays, respectively. We discuss the binding preferences of these molecules based on their large-scale affinity profiles. In addition, we selected combinations of fluorescent indicators and different ranks of RNA based on the information and screened for RNA-binding molecules using FID. RNAs with high- and intermediate-rank RNA provided reliable results. Our system provides fundamental information about small molecule-RNA interactions and facilitates the discovery of novel RNA-binding molecules.
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Affiliation(s)
- Ryosuke Nagasawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan
| | - Kazumitsu Onizuka
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan.
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan.
- Division for the Establishment of Frontier Sciences of Organization for Advanced Studies, Tohoku University, Miyagi, 980-8577, Japan.
| | - Kaoru R Komatsu
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, 606-8507, Japan
| | - Emi Miyashita
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, 606-8507, Japan
| | - Hirotaka Murase
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
| | - Kanna Ojima
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan
| | - Shunya Ishikawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan
| | - Mamiko Ozawa
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan
| | - Hirohide Saito
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto, 606-8507, Japan.
| | - Fumi Nagatsugi
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Miyagi, 980-8577, Japan.
- Department of Chemistry, Graduate School of Science, Tohoku University, Miyagi, 980-8578, Japan.
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Zhou J, Chen Q, Ren R, Yang J, Liu B, Horton JR, Chang C, Li C, Maksoud L, Yang Y, Rotili D, Zhang X, Blumenthal RM, Chen T, Gao Y, Valente S, Mai A, Cheng X. Quinoline-based compounds can inhibit diverse enzymes that act on DNA. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.03.587980. [PMID: 38617249 PMCID: PMC11014617 DOI: 10.1101/2024.04.03.587980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
DNA methylation, as exemplified by cytosine-C5 methylation in mammals and adenine-N6 methylation in bacteria, is a crucial epigenetic mechanism driving numerous vital biological processes. Developing non-nucleoside inhibitors to cause DNA hypomethylation is a high priority, in order to treat a variety of significant medical conditions without the toxicities associated with existing cytidine-based hypomethylating agents. In this study, we have characterized fifteen quinoline-based analogs. Notably, compounds with additions like a methylamine ( 9 ) or methylpiperazine ( 11 ) demonstrate similar low micromolar inhibitory potency against both human DNMT1 (which generates C5-methylcytosine) and Clostridioides difficile CamA (which generates N6-methyladenine). Structurally, compounds 9 and 11 specifically intercalate into CamA-bound DNA via the minor groove, adjacent to the target adenine, leading to a substantial conformational shift that moves the catalytic domain away from the DNA. This study adds to the limited examples of DNA methyltransferases being inhibited by non-nucleotide compounds through DNA intercalation, following the discovery of dicyanopyridine-based inhibitors for DNMT1. Furthermore, our study shows that some of these quinoline-based analogs inhibit other enzymes that act on DNA, such as polymerases and base excision repair glycosylases. Finally, in cancer cells compound 11 elicits DNA damage response via p53 activation. Abstract Figure Highlights Six of fifteen quinoline-based derivatives demonstrated comparable low micromolar inhibitory effects on human cytosine methyltransferase DNMT1, and the bacterial adenine methyltransferases Clostridioides difficile CamA and Caulobacter crescentus CcrM. Compounds 9 and 11 were found to intercalate into a DNA substrate bound by CamA. These quinoline-based derivatives also showed inhibitory activity against various base excision repair DNA glycosylases, and DNA and RNA polymerases. Compound 11 provokes DNA damage response via p53 activation in cancer cells.
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Kim HY, Kim JH. Chemical Characterization of the Precipitate Found in and Its Effect on Drug Release of the Scutellaria baicalensis-Coptis chinensis Extract. Chem Biodivers 2023; 20:e202301461. [PMID: 37961037 DOI: 10.1002/cbdv.202301461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 11/10/2023] [Accepted: 11/13/2023] [Indexed: 11/15/2023]
Abstract
Precipitate generation is a challenging issue during the production of herbal decoction as it affects the stability and bioavailability of active compounds. Here we explored the composition of the natural precipitate formed from and its effect on drug release of Scutellaria baicalensis-Coptis chinensis paired extract (SCPE). Furthermore, the surface morphology of the SCPE precipitate was also investigated. Ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) was used to chemical component analysis and field emission scanning electron microscope (FE-SEM) was performed to particle observation. Baicalin (BA), berberine (BBR) and starch-arginine-rich polymers were abundant in the SCPE precipitate. FE-SEM micrographs showed spheroidal shaped particles in the SCPE supernatant, while spherical and porous tissue-shaped particles in the SCPE precipitate. In vitro drug release of baicalin and berberine contained in the precipitate may increase as the polymer is removed. The presence of polymer-related interactions were confirmed by the greater increase in solubility of baicalin upon addition of arginine and polymer. This was also supported by the solubility decrease of the BA-BBR complex in polymer solution and the gelation of the BA-BBR complex in arginine solution. Our results provide a scientific basis for elucidating the pharmaceutical properties of the decoction of S. baicalensis-C. chinensis-based herbal medicine.
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Affiliation(s)
- Han-Young Kim
- Research Institute for Korean Medicine, Pusan National University, Yangsan, Republic of Korea, 50612
| | - Jung-Hoon Kim
- Division of Pharmacology, School of Korean Medicine, Pusan National University, Yangsan, Republic of Korea, 50612
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Das S, Takahashi S, Ohyama T, Bhowmik S, Sugimoto N. Theranostic approach to specifically targeting the interloop region of BCL2 i-motif DNA by crystal violet. Sci Rep 2023; 13:14338. [PMID: 37658102 PMCID: PMC10474294 DOI: 10.1038/s41598-023-39407-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 07/25/2023] [Indexed: 09/03/2023] Open
Abstract
Ligands that recognise specific i-motif DNAs are helpful in cancer diagnostics and therapeutics, as i-motif formation can cause cancer. Although the loop regions of i-motifs are promising targets for ligands, the interaction between a ligand and the loop regions based on sequence information remains unexplored. Herein, we investigated the loop regions of various i-motif DNAs to determine whether these regions specifically interact with fluorescent ligands. Crystal violet (CV), a triphenylmethane dye, exhibited strong fluorescence with the i-motif derived from the promoter region of the human BCL2 gene in a sequence- and structure-specific manner. Our systematic sequence analysis indicated that CV was bound to the site formed by the first and third loops through inter-loop interactions between the guanine bases present in these loops. As the structural stability of the BCL2 i-motif was unaffected by CV, the local stabilisation of the loops by CV could inhibit the interaction of transcription factors with these loops, repressing the BCL2 expression of MCF-7 cells. Our finding suggests that the loops of the i-motif can act as a novel platform for the specific binding of small molecules; thus, they could be utilised for the theranostics of diseases associated with i-motif DNAs.
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Affiliation(s)
- Sinjan Das
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Kobe, 650-0047, Japan
| | - Shuntaro Takahashi
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Kobe, 650-0047, Japan
| | - Tatsuya Ohyama
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Kobe, 650-0047, Japan
| | - Sudipta Bhowmik
- Department of Biophysics, Molecular Biology and Bioinformatics, University of Calcutta, 92, A.P.C Road, Kolkata, 700009, India
- Mahatma Gandhi Medical Advanced Research Institute (MGMARI), Sri Balaji Vidyapeeth (Deemed to be University), Pondy-Cuddalore Main Road, Pillayarkuppam, Pondicherry, 607402, India
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-Minamimachi, Kobe, 650-0047, Japan.
- Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-Minamimachi, Kobe, 650-0047, Japan.
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Ryan C, Rahman MM, Kumar V, Rozners E. Triplex-Forming Peptide Nucleic Acid Controls Dynamic Conformations of RNA Bulges. J Am Chem Soc 2023; 145:10497-10504. [PMID: 37155726 PMCID: PMC10198159 DOI: 10.1021/jacs.2c12488] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Indexed: 05/10/2023]
Abstract
RNA folding is driven by the formation of double-helical segments interspaced by loops of unpaired nucleotides. Among the latter, bulges formed by one or several unpaired nucleotides are one of the most common structural motifs that play an important role in stabilizing RNA-RNA, RNA-protein, and RNA-small molecule interactions. Single-nucleotide bulges can fold in alternative structures where the unpaired nucleobase is either looped-out (flexible) in a solvent or stacked-in (intercalated) between the base pairs. In the present study, we discovered that triplex-forming peptide nucleic acids (PNAs) had unusually high affinity for single-purine-nucleotide bulges in double-helical RNA. Depending on the PNA's sequence, the triplex formation shifted the equilibrium between looped-out and stacked-in conformations. The ability to control the dynamic equilibria of RNA's structure will be an important tool for studying structure-function relationships in RNA biology and may have potential in novel therapeutic approaches targeting disease-related RNAs.
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Affiliation(s)
- Christopher
A. Ryan
- Department of Chemistry, The State
University of New York, Binghamton University, Binghamton, New York 13902, United States
| | - Md Motiar Rahman
- Department of Chemistry, The State
University of New York, Binghamton University, Binghamton, New York 13902, United States
| | - Vipin Kumar
- Department of Chemistry, The State
University of New York, Binghamton University, Binghamton, New York 13902, United States
| | - Eriks Rozners
- Department of Chemistry, The State
University of New York, Binghamton University, Binghamton, New York 13902, United States
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Endoh T, Takahashi S, Sugimoto N. Endogenous G-quadruplex-forming RNAs inhibit the activity of SARS-CoV-2 RNA polymerase. Chem Commun (Camb) 2023; 59:872-875. [PMID: 36594508 DOI: 10.1039/d2cc05858h] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Replication of RNA viruses is catalysed by virus-specific polymerases, which can be targets of therapeutic strategies. In this study, we used a selection strategy to identify endogenous RNAs from a transcriptome library derived from lung cells that interact with the RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2. Some of the selected RNAs weakened the activity of RdRp by forming G-quadruplexes. These results suggest that certain endogenous RNAs, which potentially form G-quadruplexes, can reduce the replication of viral RNAs.
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Affiliation(s)
- Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Kobe, 650-0047, Japan.
| | - Shuntaro Takahashi
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Kobe, 650-0047, Japan.
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Kobe, 650-0047, Japan. .,Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-minamimachi, Kobe, 650-0047, Japan
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7
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Endoh T, Tan JH, Chen SB, Sugimoto N. Cladogenetic Orthogonal Light-Up Aptamers for Simultaneous Detection of Multiple Small Molecules in Cells. Anal Chem 2023; 95:976-985. [PMID: 36541622 DOI: 10.1021/acs.analchem.2c03598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Recent successes in construction of light-up RNA aptamers allowed fluorescence-based live-cell imaging of RNAs. In addition, light-up aptamers have been converted into signaling aptamers that enable fluorometric detection of small chemicals. To date, only a single target chemical has been detected at a time in cells. In this study, we selected cladogenetic orthogonal light-up aptamers that output three different colors from the RNA library having the same ligand binding core. Two of the three functioned in mammalian cells. These two aptamers, which fluoresce blue and green upon binding of cognate fluorogen, were converted into signaling aptamers. Using these signaling aptamers in combination with a previously described light-up aptamer with red fluorescence, we demonstrated simultaneous detection of multiple chemicals in living cells. The cladogenetic orthogonal light-up aptamers developed in this study and the simple strategy for rational designing of the signaling aptamers will provide innovative advances in the field of RNA-based bioimaging.
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Affiliation(s)
- Tamaki Endoh
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Kobe650-0047, Japan
| | - Jia-Heng Tan
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou510006, China
| | - Shuo-Bin Chen
- School of Pharmaceutical Sciences, Sun Yat-sen University, Guangzhou510006, China
| | - Naoki Sugimoto
- Frontier Institute for Biomolecular Engineering Research (FIBER), Konan University, 7-1-20 Minatojima-minamimachi, Kobe650-0047, Japan.,Graduate School of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-minamimachi, Kobe650-0047, Japan
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8
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Ghosh A, Trajkovski M, Teulade‐Fichou M, Gabelica V, Plavec J. Phen-DC 3 Induces Refolding of Human Telomeric DNA into a Chair-Type Antiparallel G-Quadruplex through Ligand Intercalation. Angew Chem Int Ed Engl 2022; 61:e202207384. [PMID: 35993443 PMCID: PMC9826182 DOI: 10.1002/anie.202207384] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Indexed: 01/11/2023]
Abstract
Human telomeric G-quadruplex DNA structures are attractive anticancer drug targets, but the target's polymorphism complicates the drug design: different ligands prefer different folds, and very few complexes have been solved at high resolution. Here we report that Phen-DC3 , one of the most prominent G-quadruplex ligands in terms of high binding affinity and selectivity, causes dTAGGG(TTAGGG)3 to completely change its fold in KCl solution from a hybrid-1 to an antiparallel chair-type structure, wherein the ligand intercalates between a two-quartet unit and a pseudo-quartet, thereby ejecting one potassium ion. This unprecedented high-resolution NMR structure shows for the first time a true ligand intercalation into an intramolecular G-quadruplex.
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Affiliation(s)
- Anirban Ghosh
- CNRS, INSERM, ARNA, UMR 5320, U1212, IECBUniversité de Bordeaux33600PessacFrance
| | - Marko Trajkovski
- Slovenian NMR CentreNational Institute of ChemistryHajdrihova 191000LjubljanaSlovenia
| | | | - Valérie Gabelica
- CNRS, INSERM, ARNA, UMR 5320, U1212, IECBUniversité de Bordeaux33600PessacFrance
| | - Janez Plavec
- Slovenian NMR CentreNational Institute of ChemistryHajdrihova 191000LjubljanaSlovenia,Faculty of Chemistry and Chemical TechnologyUniversity of Ljubljana1000LjubljanaSlovenia,EN-FIST, Centre of Excellence1000LjubljanaSlovenia
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9
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Ghosh A, Trajkovski M, Teulade-Fichou MP, Gabelica V, Plavec J. Phen‐DC3 Induces Refolding of Human Telomeric DNA into a Chair‐type Antiparallel G‐quadruplex through Ligand Intercalation. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202207384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Anirban Ghosh
- IECB: Institut Europeen de Chimie et Biologie ARNA FRANCE
| | - Marko Trajkovski
- National Institute of Chemistry Slovenia: Kemijski institut Slovenian NMR centre SLOVENIA
| | | | | | - Janez Plavec
- National Institute of Chemistry NMR centre Hajdrihova 19 SI-1001 Ljubljana SLOVENIA
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Li W, Liu X, Tan LF. Binding properties of [Ru(phen)2(11-R-dppz)]2+ (R = F or CN) with poly(A)•poly(U) duplex RNA. J Inorg Biochem 2022; 232:111833. [DOI: 10.1016/j.jinorgbio.2022.111833] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2022] [Revised: 04/06/2022] [Accepted: 04/12/2022] [Indexed: 10/18/2022]
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11
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Horton JR, Pathuri S, Wong K, Ren R, Rueda L, Fosbenner DT, Heerding DA, McCabe MT, Pappalardi MB, Zhang X, King BW, Cheng X. Structural characterization of dicyanopyridine containing DNMT1-selective, non-nucleoside inhibitors. Structure 2022; 30:793-802.e5. [PMID: 35395178 PMCID: PMC9177618 DOI: 10.1016/j.str.2022.03.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/24/2022] [Accepted: 03/11/2022] [Indexed: 12/21/2022]
Abstract
DNMT1 maintains the parental DNA methylation pattern on newly replicated hemimethylated DNA. The failure of this maintenance process causes aberrant DNA methylation that affects transcription and contributes to the development and progression of cancers such as acute myeloid leukemia. Here, we structurally characterized a set of newly discovered DNMT1-selective, reversible, non-nucleoside inhibitors that bear a core 3,5-dicyanopyridine moiety, as exemplified by GSK3735967, to better understand their mechanism of inhibition. All of the dicyanopydridine-containing inhibitors examined intercalate into the hemimethylated DNA between two CpG base pairs through the DNA minor groove, resulting in conformational movement of the DNMT1 active-site loop. In addition, GSK3735967 introduces two new binding sites, where it interacts with and stabilizes the displaced DNMT1 active-site loop and it occupies an open aromatic cage in which trimethylated histone H4 lysine 20 is expected to bind. Our work represents a substantial step in generating potent, selective, and non-nucleoside inhibitors of DNMT1.
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Affiliation(s)
- John R Horton
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Sarath Pathuri
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Kristen Wong
- Cancer Epigenetics Research Unit, Oncology, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Ren Ren
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Lourdes Rueda
- Cancer Epigenetics Research Unit, Oncology, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - David T Fosbenner
- Cancer Epigenetics Research Unit, Oncology, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Dirk A Heerding
- Cancer Epigenetics Research Unit, Oncology, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Michael T McCabe
- Cancer Epigenetics Research Unit, Oncology, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Melissa B Pappalardi
- Cancer Epigenetics Research Unit, Oncology, GlaxoSmithKline, Collegeville, PA 19426, USA
| | - Xing Zhang
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Bryan W King
- Cancer Epigenetics Research Unit, Oncology, GlaxoSmithKline, Collegeville, PA 19426, USA.
| | - Xiaodong Cheng
- Department of Epigenetics and Molecular Carcinogenesis, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA.
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