1
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Rigo R, Groaz E, Sissi C. Polymorphic and Higher-Order G-Quadruplexes as Possible Transcription Regulators: Novel Perspectives for Future Anticancer Therapeutic Applications. Pharmaceuticals (Basel) 2022; 15:ph15030373. [PMID: 35337170 PMCID: PMC8950063 DOI: 10.3390/ph15030373] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Revised: 03/14/2022] [Accepted: 03/15/2022] [Indexed: 02/06/2023] Open
Abstract
In the past two decades, significant efforts have been put into designing small molecules to target selected genomic sites where DNA conformational rearrangements control gene expression. G-rich sequences at oncogene promoters are considered good points of intervention since, under specific environmental conditions, they can fold into non-canonical tetrahelical structures known as G-quadruplexes. However, emerging evidence points to a frequent lack of correlation between small molecule targeting of G-quadruplexes at gene promoters and the expression of the associated protein, which hampers pharmaceutical applications. The wide genomic localization of G-quadruplexes along with their highly polymorphic behavior may account for this scenario, suggesting the need for more focused drug design strategies. Here, we will summarize the G4 structural features that can be considered to fulfill this goal. In particular, by comparing a telomeric sequence with the well-characterized G-rich domain of the KIT promoter, we will address how multiple secondary structures might cooperate to control genome architecture at a higher level. If this holds true, the link between drug–DNA complex formation and the associated cellular effects will need to be revisited.
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Affiliation(s)
- Riccardo Rigo
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Marzolo 5, 35131 Padova, Italy; (R.R.); (E.G.)
- CEITEC—Central European Institute of Technology, Masaryk University, Kamenice 753/5, 625 00 Brno, Czech Republic
| | - Elisabetta Groaz
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Marzolo 5, 35131 Padova, Italy; (R.R.); (E.G.)
- KU Leuven, Rega Institute for Medical Research, Medicinal Chemistry, Herestraat 49-Box 1041, 3000 Leuven, Belgium
| | - Claudia Sissi
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Marzolo 5, 35131 Padova, Italy; (R.R.); (E.G.)
- Correspondence:
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2
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Miron CE, Chen M, Mergny JL, Petitjean A. Portrait of a Family of Highly Stabilizing and Selective Guanine Quadruplex Platinum(II)-Based Binders. Chemistry 2021; 28:e202103839. [PMID: 34862673 DOI: 10.1002/chem.202103839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Indexed: 11/12/2022]
Abstract
The long-standing history of platinum coordination complexes in nucleic acid recognition attests to the unique suitability of such species for therapeutic applications. Here, we report the synthetic exploration and development of a family of di-imine ligands, and their platinum(II) complexes, elaborated on a 3-(2-pyridyl)-[1,2,4]triazolo[4,3-a]pyridine platform which, in its unsubstituted form, has recently been shown to display exceptional capabilities for guanine quadruplex (G4) targeting. The identification of facile, high-yielding synthetic methods for the derivatization of this platform for the incorporation of additional sites of interactions with guanine quadruplex loops and grooves, along with the optimization of platinum(II) complexation methods, are discussed. Gratifyingly, preliminary biophysical screening of this novel family of binders validates all but one family members as robust G4 binders and highlights enhanced selectivity for quadruplex versus duplex DNA compared to the parent compound. These results bear promise for practical developments based on this platform.
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Affiliation(s)
- Caitlin E Miron
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, ON K7L3N6, Canada.,Department of Chemistry, McGill University, 801 Sherbrooke St. West, Montreal, QC H3A0B8, Canada
| | - Mickey Chen
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, ON K7L3N6, Canada
| | - Jean-Louis Mergny
- Institut Européen de Chimie et Biologie, 2 rue Escarpit, F-33607, Pessac, France.,Laboratoire d'Optique et Biosciences, École Polytechnique, CNRS, INSERM, Institut Polytechnique de Paris, 91128, Palaiseau cedex, France
| | - Anne Petitjean
- Department of Chemistry, Queen's University, 90 Bader Lane, Kingston, ON K7L3N6, Canada
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3
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Winnerdy FR, Bakalar B, Das P, Heddi B, Marchand A, Rosu F, Gabelica V, Phan AT. Unprecedented hour-long residence time of a cation in a left-handed G-quadruplex. Chem Sci 2021; 12:7151-7157. [PMID: 34123342 PMCID: PMC8153214 DOI: 10.1039/d1sc00515d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Accepted: 04/06/2021] [Indexed: 11/21/2022] Open
Abstract
Cations are critical for the folding and assembly of nucleic acids. In G-quadruplex structures, cations can bind between stacked G-tetrads and coordinate with negatively charged guanine carbonyl oxygens. They usually exchange between binding sites and with the bulk in solution with time constants ranging from sub-millisecond to seconds. Here we report the first observation of extremely long-lived K+ and NH4 + ions, with an exchange time constant on the order of an hour, when coordinated at the center of a left-handed G-quadruplex DNA. A single-base mutation, that switched one half of the structure from left- to right-handed conformation resulting in a right-left hybrid G-quadruplex, was shown to remove this long-lived behaviour of the central cation.
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Affiliation(s)
- Fernaldo Richtia Winnerdy
- School of Physical and Mathematical Sciences, Nanyang Technological University Singapore 637371 Singapore
| | - Blaž Bakalar
- School of Physical and Mathematical Sciences, Nanyang Technological University Singapore 637371 Singapore
| | - Poulomi Das
- School of Physical and Mathematical Sciences, Nanyang Technological University Singapore 637371 Singapore
| | - Brahim Heddi
- School of Physical and Mathematical Sciences, Nanyang Technological University Singapore 637371 Singapore
- Laboratoire de Biologie et de Pharmacologie Appliquée, CNRS, Ecole Normale Supérieure Paris-Saclay Gif-sur-Yvette 91190 France
| | - Adrien Marchand
- Laboratoire Acides Nucléiques: Régulations Naturelle et Artificielle, Université de Bordeaux, Inserm & CNRS (ARNA, U1212, UMR5320), IECB Pessac 33600 France
| | - Frédéric Rosu
- Institut Européen de Chimie et Biologie, Université de Bordeaux, CNRS & Inserm (IECB, UMS3033, US001) Pessac 33607 France
| | - Valérie Gabelica
- Laboratoire Acides Nucléiques: Régulations Naturelle et Artificielle, Université de Bordeaux, Inserm & CNRS (ARNA, U1212, UMR5320), IECB Pessac 33600 France
| | - Anh Tuân Phan
- School of Physical and Mathematical Sciences, Nanyang Technological University Singapore 637371 Singapore
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4
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Weynand J, Moreno-Betancourt A, Loiseau F, Berthet N, Defrancq E, Elias B. Redox-Active Bis-Cyclometalated Iridium(III) Complex as a DNA Photo-Cleaving Agent. Inorg Chem 2020; 59:2426-2433. [PMID: 31977196 DOI: 10.1021/acs.inorgchem.9b03312] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The development of new photoactive metal complexes that can trigger oxidative damages to the genetic material is of great interest. In the present paper, we describe the detailed study of a highly photo-oxidant iridium(III) complex that triggers photoinduced electron transfer (PET) with purine DNA bases. The PET has been studied by luminescence and laser flash photolysis experiments. From plasmid DNA agarose gel electrophoresis experiments, we demonstrated the high ability of the iridium complex to induce strand breaks upon light irradiation. Reactive oxygen species (ROS)-specific scavengers and stabilizers were employed to identify that the photocleavage process, the results of which infer singlet oxygen and hydrogen peroxide as the predominant species. To the best of our knowledge, the present work represents one of the few study for highly photo-oxidant bis-cyclometalated iridium(III) complex toward DNA.
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Affiliation(s)
- Justin Weynand
- Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis Division (MOST) , Université catholique de Louvain (UCLouvain) , Place Louis Pasteur 1, bte L4.01.02 , B-1348 Louvain-la-Neuve , Belgium.,Département de Chimie Moléculaire, UMR CNRS 5250 , Université Grenoble Alpes , CS 40700, 38058 Grenoble , France
| | - Angélica Moreno-Betancourt
- Département de Chimie Moléculaire, UMR CNRS 5250 , Université Grenoble Alpes , CS 40700, 38058 Grenoble , France
| | - Frédérique Loiseau
- Département de Chimie Moléculaire, UMR CNRS 5250 , Université Grenoble Alpes , CS 40700, 38058 Grenoble , France
| | - Nathalie Berthet
- Département de Chimie Moléculaire, UMR CNRS 5250 , Université Grenoble Alpes , CS 40700, 38058 Grenoble , France
| | - Eric Defrancq
- Département de Chimie Moléculaire, UMR CNRS 5250 , Université Grenoble Alpes , CS 40700, 38058 Grenoble , France
| | - Benjamin Elias
- Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis Division (MOST) , Université catholique de Louvain (UCLouvain) , Place Louis Pasteur 1, bte L4.01.02 , B-1348 Louvain-la-Neuve , Belgium
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5
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G-Quadruplex Binders Induce Immunogenic Cell Death Markers in Aggressive Breast Cancer Cells. Cancers (Basel) 2019; 11:cancers11111797. [PMID: 31731707 PMCID: PMC6895816 DOI: 10.3390/cancers11111797] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 11/12/2019] [Indexed: 02/06/2023] Open
Abstract
Background: DNA G-quadruplex (G4) structures represent potential anti-cancer targets. In this study, we compared the effect of two G4-targeting compounds, C066-3108 and the gold standard BRACO-19. Methods: In breast and prostate cancer cells, cytotoxicity induced by both molecules was measured by a sulforhodamine B assay. In breast cancer cells, cycle, apoptosis, the formation of G4 structures, calreticulin and high mobility group box 1 (HMGB1), as well as T cell activation, were analyzed by flow cytometry and adenosine triphosphate (ATP) by luminescence. Results: Both ligands inhibited cell survival and induced DNA damage. In MCF-7 cells, G4 ligands increased the subG0/G1 phase of the cell cycle inducing apoptosis and reduced intracellular ATP. In untreated MCF-7 cells, we observed a slight presence of G4 structures associated with the G2/M phase. In MDA-MB231 cells, G4 ligands decreased the G1 and enhanced the G2/M phase. We observed a decrease of intracellular ATP, calreticulin cell surface exposure and an increase of HMGB1, accompanied by T cell activation. Both compounds induced G4 structure formation in the subG0/G1 phase. Conclusions: Our data report similar effects for both compounds and the first evidence that G4 ligands induce the release of danger signals associated with immunogenic cell death and induction of T cell activation.
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Abstract
Herein, we report a C-N coupling reaction via antiaromatic endocyclic nitrenium ions. The nitrenium ion intermediate was generated by a combination of iodine(III) reagent PhI(OCOCF3)2 and the N-H center of benzimidazole units at ambient laboratory conditions. Metal-free synthesis of benzimidazole-fused phenanthridine derivatives was achieved in good to excellent yields.
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Affiliation(s)
- Shyamal Kanti Bera
- School of Chemical Sciences , National Institute of Science Education and Research (NISER), HBNI , PO Bhimpur-Padanpur, Via Jatni , District Khurda, Bhubaneswar , Odisha 752050 , India
| | - Md Toufique Alam
- School of Chemical Sciences , National Institute of Science Education and Research (NISER), HBNI , PO Bhimpur-Padanpur, Via Jatni , District Khurda, Bhubaneswar , Odisha 752050 , India
| | - Prasenjit Mal
- School of Chemical Sciences , National Institute of Science Education and Research (NISER), HBNI , PO Bhimpur-Padanpur, Via Jatni , District Khurda, Bhubaneswar , Odisha 752050 , India
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7
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Weynand J, Bonnet H, Loiseau F, Ravanat JL, Dejeu J, Defrancq E, Elias B. Targeting G-Rich DNA Structures with Photoreactive Bis-Cyclometallated Iridium(III) Complexes. Chemistry 2019; 25:12730-12739. [PMID: 31290208 DOI: 10.1002/chem.201902183] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 07/02/2019] [Indexed: 01/19/2023]
Abstract
The synthesis and characterisation of three novel iridium(III) bis-cyclometallated complexes is reported. Their photophysics have been fully characterised by classical methods and revealed charge-transfer (CT) and ligand-centred (LC) transitions. Their ability to selectively interact with G-quadruplex telomeric DNA over duplex DNA has been studied by circular dichroism (CD), bio-layer interferometry (BLI) and surface plasmon resonance (SPR) analyses. Interestingly, one of the complexes was able to promote photoinduced electron transfer (PET) with the guanine DNA base, which in turn led to oxidative damage (such as the formation of 8-oxoguanine) to the telomeric sequence. To the best of our knowledge, this is the first study of highly photo-oxidising bis-cyclometallated iridium(III) complexes with G-quadruplex telomeric DNA.
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Affiliation(s)
- Justin Weynand
- Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Université catholique de Louvain (UCLouvain), Place Louis Pasteur 1, bte L4.01.02, 1348, Louvain-la-Neuve, Belgium.,CNRS, DCM UMR5250, Université Grenoble Alpes, 38000, Grenoble, France
| | - Hughes Bonnet
- CNRS, DCM UMR5250, Université Grenoble Alpes, 38000, Grenoble, France
| | | | - Jean-Luc Ravanat
- CEA, CNRS, INAC-SyMMES, Université Grenoble Alpes, 17 rue des martyrs, 38054, Grenoble CEDEX 9, France
| | - Jérôme Dejeu
- CNRS, DCM UMR5250, Université Grenoble Alpes, 38000, Grenoble, France
| | - Eric Defrancq
- CNRS, DCM UMR5250, Université Grenoble Alpes, 38000, Grenoble, France
| | - Benjamin Elias
- Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST), Université catholique de Louvain (UCLouvain), Place Louis Pasteur 1, bte L4.01.02, 1348, Louvain-la-Neuve, Belgium
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8
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Challenges and current status of computational methods for docking small molecules to nucleic acids. Eur J Med Chem 2019; 168:414-425. [PMID: 30831409 DOI: 10.1016/j.ejmech.2019.02.046] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2018] [Revised: 02/12/2019] [Accepted: 02/12/2019] [Indexed: 01/29/2023]
Abstract
Since the development of the first docking program in 1982, the use of docking-based in silico screening for potentially bioactive molecule discovery has become a common strategy in academia and pharmaceutical industry. Up until recently, application of docking programs has largely focused on drugs binding to proteins. However, with the discovery of promising drug targets in nucleic acids, including RNA riboswitches, DNA G-quadruplexes, and extended repeats in RNA, there has been greater interests in developing drugs for nucleic acids. However, due to major biochemical and physical differences in charges, binding pockets, and solvation, existing docking programs, developed for proteins, face difficulties when adopted directly for nucleic acids. In this review, we cover the current field of in silico docking to nucleic acids, available programs, as well as challenges faced in the field.
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9
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Saha P, Panda D, Dash J. The application of click chemistry for targeting quadruplex nucleic acids. Chem Commun (Camb) 2019; 55:731-750. [PMID: 30489575 DOI: 10.1039/c8cc07107a] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The Cu(i)-catalyzed azide and alkyne 1,3-dipolar cycloaddition (CuAAC), commonly known as the "click reaction", has emerged as a powerful and versatile synthetic tool that finds a broad spectrum of applications in chemistry, biology and materials science. The efficiency, selectivity and versatility of the CuAAC reactions have enabled the preparation of vast arrays of triazole compounds with biological and pharmaceutical applications. In this feature article, we outline the applications and future prospects of click chemistry in the synthesis and development of small molecules that target G-quadruplex nucleic acids and show promising biological activities. Furthermore, this article highlights the template-assisted in situ click chemistry for developing G-quadruplex specific ligands and the use of click chemistry for enhancing drug specificity as well as designing imaging and sensor systems to elucidate the biological functions of G-quadruplex nucleic acids in live cells.
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Affiliation(s)
- Puja Saha
- School of Chemical Sciences, Indian Association for the Cultivation of Science, Jadavpur, Kolkata-700032, India.
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10
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Weynand J, Diman A, Abraham M, Marcélis L, Jamet H, Decottignies A, Dejeu J, Defrancq E, Elias B. Towards the Development of Photo‐Reactive Ruthenium(II) Complexes Targeting Telomeric G‐Quadruplex DNA. Chemistry 2018; 24:19216-19227. [DOI: 10.1002/chem.201804771] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 10/22/2018] [Indexed: 12/11/2022]
Affiliation(s)
- Justin Weynand
- Université catholique de Louvain (UCLouvain)Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST) Place Louis Pasteur 1, bte L4.01.02 1348 Louvain-la-Neuve Belgium
- Université Grenoble-Alpes (UGA)Département de Chimie Moléculaire, UMR CNRS 5250, CS 40700 38058 Grenoble France
| | - Aurélie Diman
- Université catholique de Louvain (UCLouvain) de Duve Institute Avenue Hippocrate 75 1200 Brussels Belgium
| | - Michaël Abraham
- Université catholique de Louvain (UCLouvain)Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST) Place Louis Pasteur 1, bte L4.01.02 1348 Louvain-la-Neuve Belgium
| | - Lionel Marcélis
- Université catholique de Louvain (UCLouvain)Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST) Place Louis Pasteur 1, bte L4.01.02 1348 Louvain-la-Neuve Belgium
| | - Hélène Jamet
- Université Grenoble-Alpes (UGA)Département de Chimie Moléculaire, UMR CNRS 5250, CS 40700 38058 Grenoble France
| | - Anabelle Decottignies
- Université catholique de Louvain (UCLouvain) de Duve Institute Avenue Hippocrate 75 1200 Brussels Belgium
| | - Jérôme Dejeu
- Université Grenoble-Alpes (UGA)Département de Chimie Moléculaire, UMR CNRS 5250, CS 40700 38058 Grenoble France
| | - Eric Defrancq
- Université Grenoble-Alpes (UGA)Département de Chimie Moléculaire, UMR CNRS 5250, CS 40700 38058 Grenoble France
| | - Benjamin Elias
- Université catholique de Louvain (UCLouvain)Institut de la Matière Condensée et des Nanosciences (IMCN), Molecular Chemistry, Materials and Catalysis (MOST) Place Louis Pasteur 1, bte L4.01.02 1348 Louvain-la-Neuve Belgium
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11
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Garci A, Castor KJ, Fakhoury J, Do JL, Di Trani J, Chidchob P, Stein RS, Mittermaier AK, Friščić T, Sleiman H. Efficient and Rapid Mechanochemical Assembly of Platinum(II) Squares for Guanine Quadruplex Targeting. J Am Chem Soc 2017; 139:16913-16922. [PMID: 29058892 DOI: 10.1021/jacs.7b09819] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
We present a rapid and efficient method to generate a family of platinum supramolecular square complexes, including previously inaccessible targets, through the use of ball milling mechanochemistry. This one-pot, two-step process occurs in minutes and enables the synthesis of the squares [Pt4(en)4(N∩N)4][CF3SO3]8 (en= ethylenediamine, N∩N = 4,4'-bipyridine derivatives) from commercially available precursor K2PtCl4 in good to excellent yields. In contrast, solution-based assembly requires heating the reagents for weeks and gives lower yields. Mechanistic investigations into this remarkable rate acceleration revealed that solution-based assembly (refluxing for days) results in the formation of large oligomeric side-products that are difficult to break down into the desired squares. On the other hand, ball milling in the solid state is rapid and appears to involve smaller intermediates. We examined the binding of the new supramolecular squares to guanine quadruplexes, including oncogene and telomere-associated DNA and RNA sequences. Sub-micromolar binding affinities were obtained by fluorescence displacement assays (FID) and isothermal titration calorimetry (ITC), with binding preference to telomere RNA (TERRA) sequences. ITC showed a 1:1 binding stoichiometry of the metallosquare to TERRA, while the stoichiometry was more complex for telomeric quadruplex DNA and a double-stranded DNA control.
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Affiliation(s)
- Amine Garci
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Katherine J Castor
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Johans Fakhoury
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Jean-Louis Do
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Justin Di Trani
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Pongphak Chidchob
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Robin S Stein
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Anthony K Mittermaier
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Tomislav Friščić
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
| | - Hanadi Sleiman
- Department of Chemistry, McGill University , 801 Sherbrooke Street West, Montréal, Québec H3A 0B8, Canada
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12
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Qin QP, Qin JL, Chen M, Li YL, Meng T, Zhou J, Liang H, Chen ZF. Chiral platinum (II)-4-(2,3-dihydroxypropyl)- formamide oxo-aporphine (FOA) complexes promote tumor cells apoptosis by directly targeting G-quadruplex DNA in vitro and in vivo. Oncotarget 2017; 8:61982-61997. [PMID: 28977920 PMCID: PMC5617480 DOI: 10.18632/oncotarget.18778] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2017] [Accepted: 05/06/2017] [Indexed: 11/25/2022] Open
Abstract
Three platinum(II) complexes, 4 (LC-004), 5 (LC-005), and 6 (LC-006), with the chiral FOA ligands R/S-(±)-FOA (1), R-(+)-FOA (2) and S-(–)-FOA (3), respectively, were synthesized and characterized. As potential anti-tumor agents, these complexes show higher cytotoxicity to BEL-7404 cells than the HL-7702 normal cells. They are potential telomerase inhibitors that target c-myc and human telomeric G-quadruplex DNA. Compared to complexes 4 and 5, 6 exhibited higher binding affinities towards telomeric, c-myc G-quadruplex DNA and caspase-3/9, thereby inducing senescence and apoptosis to a greater extent in tumor cells. Moreover, our in vivo studies showed that complex 6 can effectively inhibit tumor growth in the BEL-7404 and BEL-7402 xenograft mouse models and is less toxic than 5-fluorouracil and cisplatin. The effective inhibition of tumor growth is attributed to its interactions with 53BP1, TRF1, c-myc, TRF2, and hTERT. Thus, complex 6 can serve as a novel lead compound and a potential drug candidate for anticancer chemotherapy.
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Affiliation(s)
- Qi-Pin Qin
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, P. R. China
| | - Jiao-Lan Qin
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, P. R. China
| | - Ming Chen
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, P. R. China
| | - Yu-Lan Li
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, P. R. China
| | - Ting Meng
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, P. R. China
| | - Jie Zhou
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, P. R. China
| | - Hong Liang
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, P. R. China
| | - Zhen-Feng Chen
- State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, Guilin 541004, P. R. China
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13
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Gresh N, Naseem-Khan S, Lagardère L, Piquemal JP, Sponer JE, Sponer J. Channeling through Two Stacked Guanine Quartets of One and Two Alkali Cations in the Li +, Na +, K +, and Rb + Series. Assessment of the Accuracy of the SIBFA Anisotropic Polarizable Molecular Mechanics Potential. J Phys Chem B 2017; 121:3997-4014. [PMID: 28363025 DOI: 10.1021/acs.jpcb.7b01836] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Stacking of guanine quartets (GQs) can trigger the formation of DNA or RNA quadruple helices, which play numerous biochemical roles. The GQs are stabilized by alkali cations, mainly K+ and Na+, which can reside in, or channel through, the central axis of the GQ stems. Further, ion conduction through GQ wires can be leveraged for nanochemistry applications. G-quadruplex systems have been extensively studied by classical molecular dynamics (MD) simulations using pair-additive force fields or by quantum-chemical (QC) calculations. However, the non-polarizable force fields are very approximate, while QC calculations lack the necessary sampling. Thus, ultimate description of GQ systems would require long-enough simulations using advanced polarizable molecular mechanics (MM). However, to perform such calculations, it is first mandatory to evaluate the method's accuracy using benchmark QC. We report such an evaluation for SIBFA polarizable MM, bearing on the channeling (movement) of an alkali cation (Li+, Na+, K+, or Rb+) along the axis of two stacked G quartets interacting with either one or two ions. The QC energy profiles display markedly different features depending upon the cation but can be retrieved in the majority of cases by the SIBFA profiles. An appropriate balance of first-order (electrostatic and short-range repulsion) and second-order (polarization, charge-transfer, and dispersion) contributions within ΔE is mandatory. With two cations in the channel, the relative weights of the second-order contributions increase steadily upon increasing the ion size. In the G8 complexes with two K+ or two Rb+ cations, the sum of polarization and charge-transfer exceeds the first order terms for all ion positions.
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Affiliation(s)
- Nohad Gresh
- Laboratoire de Chimie Théorique, Sorbonne Universités , UPMC, UMR7616 CNRS, 75006Paris, France
| | - Sehr Naseem-Khan
- Laboratoire de Chimie Théorique, Sorbonne Universités , UPMC, UMR7616 CNRS, 75006Paris, France
| | - Louis Lagardère
- Laboratoire de Chimie Théorique, Sorbonne Universités , UPMC, UMR7616 CNRS, 75006Paris, France
| | - Jean-Philip Piquemal
- Laboratoire de Chimie Théorique, Sorbonne Universités , UPMC, UMR7616 CNRS, 75006Paris, France.,Institut Universitaire de France, Paris Cedex 05, 75231, France.,Department of Biomedical Engineering, The University of Texas at Austin , Austin, Texas, 78712, United States
| | - Judit E Sponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic , Kralovpolska 135, 612 65 Brno, Czech Republic.,CEITEC - Central European Institute of Technology, Masaryk University , Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
| | - Jiri Sponer
- Institute of Biophysics, Academy of Sciences of the Czech Republic , Kralovpolska 135, 612 65 Brno, Czech Republic.,CEITEC - Central European Institute of Technology, Masaryk University , Campus Bohunice, Kamenice 5, 625 00 Brno, Czech Republic
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14
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Targeting human telomeric and c-myc G-quadruplexes with alkynylplatinum(II) terpyridine complexes under molecular crowding conditions. J Inorg Biochem 2016; 166:126-134. [PMID: 27852004 DOI: 10.1016/j.jinorgbio.2016.11.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2016] [Revised: 11/05/2016] [Accepted: 11/08/2016] [Indexed: 12/27/2022]
Abstract
The interactions between alkynylplatinum(II) terpyridine complexes 1-3 and the G-quadruplex DNA, including c-myc and telomeric quadruplex DNA, are investigated both in dilute solution and under molecular crowding conditions. The UV-vis absorption spectroscopy, circular dichroism and molecular docking studies suggest that 1-3 associate with telomeric and c-myc G-quadruplexes via groove binding, and electrostatic interactions. Experimental studies indicate that under molecular crowding conditions (in the presence of 40wt% PEG 200), 1-2 show weak affinity for c-myc, while 3 still displays high affinity and selectivity for c-myc. On the other hand, 1-3 act as efficient and selective ligand for telomeric quadruplex DNA under molecular crowding conditions. The complex 3 exhibits excellent cytotoxicity against A549, K562 and SGC-7901, with IC50 values that are 35.0-fold, 10.0-fold, and 12.1-fold lower than the values of cisplatin under the same conditions, respectively.
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15
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Qin JL, Qin QP, Wei ZZ, Yu YC, Meng T, Wu CX, Liang YL, Liang H, Chen ZF. Stabilization of c-myc G-Quadruplex DNA, inhibition of telomerase activity, disruption of mitochondrial functions and tumor cell apoptosis by platinum(II) complex with 9-amino-oxoisoaporphine. Eur J Med Chem 2016; 124:417-427. [DOI: 10.1016/j.ejmech.2016.08.054] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2016] [Revised: 07/29/2016] [Accepted: 08/23/2016] [Indexed: 10/21/2022]
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16
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Moitessier N, Pottel J, Therrien E, Englebienne P, Liu Z, Tomberg A, Corbeil CR. Medicinal Chemistry Projects Requiring Imaginative Structure-Based Drug Design Methods. Acc Chem Res 2016; 49:1646-57. [PMID: 27529781 DOI: 10.1021/acs.accounts.6b00185] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Computational methods for docking small molecules to proteins are prominent in drug discovery. There are hundreds, if not thousands, of documented examples-and several pertinent cases within our research program. Fifteen years ago, our first docking-guided drug design project yielded nanomolar metalloproteinase inhibitors and illustrated the potential of structure-based drug design. Subsequent applications of docking programs to the design of integrin antagonists, BACE-1 inhibitors, and aminoglycosides binding to bacterial RNA demonstrated that available docking programs needed significant improvement. At that time, docking programs primarily considered flexible ligands and rigid proteins. We demonstrated that accounting for protein flexibility, employing displaceable water molecules, and using ligand-based pharmacophores improved the docking accuracy of existing methods-enabling the design of bioactive molecules. The success prompted the development of our own program, Fitted, implementing all of these aspects. The primary motivation has always been to respond to the needs of drug design studies; the majority of the concepts behind the evolution of Fitted are rooted in medicinal chemistry projects and collaborations. Several examples follow: (1) Searching for HDAC inhibitors led us to develop methods considering drug-zinc coordination and its effect on the pKa of surrounding residues. (2) Targeting covalent prolyl oligopeptidase (POP) inhibitors prompted an update to Fitted to identify reactive groups and form bonds with a given residue (e.g., a catalytic residue) when the geometry allows it. Fitted-the first fully automated covalent docking program-was successfully applied to the discovery of four new classes of covalent POP inhibitors. As a result, efficient stereoselective syntheses of a few screening hits were prioritized rather than synthesizing large chemical libraries-yielding nanomolar inhibitors. (3) In order to study the metabolism of POP inhibitors by cytochrome P450 enzymes (CYPs)-for toxicology studies-the program Impacts was derived from Fitted and helped us to reveal a complex metabolism with unforeseen stereocenter isomerizations. These efforts, combined with those of other docking software developers, have strengthened our understanding of the complex drug-protein binding process while providing the medicinal chemistry community with useful tools that have led to drug discoveries. In this Account, we describe our contributions over the past 15 years-within their historical context-to the design of drug candidates, including BACE-1 inhibitors, POP covalent inhibitors, G-quadruplex binders, and aminoglycosides binding to nucleic acids. We also remark the necessary developments of docking programs, specifically Fitted, that enabled structure-based design to flourish and yielded multiple fruitful, rational medicinal chemistry campaigns.
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Affiliation(s)
- Nicolas Moitessier
- Department
of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec, Canada H3A 0B8
| | - Joshua Pottel
- Department
of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec, Canada H3A 0B8
| | - Eric Therrien
- Molecular Forecaster Inc., 969
Marc-Aurèle-Fortin, Laval, Québec, Canada H7L 6H9
| | - Pablo Englebienne
- Royal HaskoningDHV, Laan 1914
35, 3818 EX Amersfoort, The Netherlands
| | - Zhaomin Liu
- Department
of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec, Canada H3A 0B8
| | - Anna Tomberg
- Department
of Chemistry, McGill University, 801 Sherbrooke Street West, Montréal, Québec, Canada H3A 0B8
| | - Christopher R. Corbeil
- Human
Health Therapeutics, National Research Council Canada, 6100 Royalmount
Avenue, Montréal, Québec, Canada H4P 2R2
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17
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CNRS Silver and Bronze Medals 2016 / Izatt-Christensen Award: H. F. Sleiman / Cram Lehn Pedersen Prize: I. Aprahamian. Angew Chem Int Ed Engl 2016; 55:6819-20. [DOI: 10.1002/anie.201604168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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Silber- und Bronzemedaillen des CNRS 2016 / Izatt-Christensen-Preis: H. F. Sleiman / Cram-Lehn-Pedersen-Preis: I. Aprahamian. Angew Chem Int Ed Engl 2016. [DOI: 10.1002/ange.201604168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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19
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Fanelli M, Formica M, Fusi V, Giorgi L, Micheloni M, Paoli P. New trends in platinum and palladium complexes as antineoplastic agents. Coord Chem Rev 2016. [DOI: 10.1016/j.ccr.2015.11.004] [Citation(s) in RCA: 165] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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20
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Ou Z, Qian Y, Gao Y, Wang Y, Yang G, Li Y, Jiang K, Wang X. Photophysical, G-quadruplex DNA binding and cytotoxic properties of terpyridine complexes with a naphthalimide ligand. RSC Adv 2016. [DOI: 10.1039/c6ra01441k] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The complex3inhibits A549 cells selectively over non-cancerous NIH3T3 cells, which may correlate with its selective G-quadruplex binding and nuclear location.
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Affiliation(s)
- Zhize Ou
- The Key Laboratory of Space Applied Physics and Chemistry
- Ministry of Education
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
| | - Yimeng Qian
- The Key Laboratory of Space Applied Physics and Chemistry
- Ministry of Education
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
| | - Yunyan Gao
- The Key Laboratory of Space Applied Physics and Chemistry
- Ministry of Education
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
| | - Yunqing Wang
- The Key Laboratory of Space Applied Physics and Chemistry
- Ministry of Education
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
| | - Guoqiang Yang
- CAS Key Laboratory of Photochemistry
- Institute of Chemistry
- Chinese Academy of Sciences
- Beijing 100190
- People's Republic of China
| | - Yi Li
- Key Laboratory of Photochemical Convesion and Optoelectronic Material
- Technical Institute of Physics and Chemistry
- Chinese Academy of Sciences
- Beijing
- People's Republic of China
| | - Kaiyue Jiang
- The Key Laboratory of Space Applied Physics and Chemistry
- Ministry of Education
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
| | - Xin Wang
- The Key Laboratory of Space Applied Physics and Chemistry
- Ministry of Education
- Department of Applied Chemistry
- School of Science
- Northwestern Polytechnical University
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21
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Zou HH, Wang L, Long ZX, Qin QP, Song ZK, Xie T, Zhang SH, Liu YC, Lin B, Chen ZF. Preparation of 4-([2,2':6',2″-terpyridin]-4'-yl)-N,N-diethylaniline Ni(II) and Pt(II) complexes and exploration of their in vitro cytotoxic activities. Eur J Med Chem 2015; 108:1-12. [PMID: 26619388 DOI: 10.1016/j.ejmech.2015.11.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Revised: 10/20/2015] [Accepted: 11/03/2015] [Indexed: 11/17/2022]
Abstract
Two metal complexes of NiLCl2 (1) and [PtLCl]Cl (2) with 4-([2,2':6',2″-terpyridin]-4'-yl)-N,N-diethylaniline (L) were synthesized and characterized. 1 and 2 exhibited selective cytotoxicity to T-24 cells more than L, compared with the normal liver cell line (HL-7702). Various experiments showed that L, 1 and 2 caused T-24 cell cycle arrest at S phase, as shown by the down-regulation of cdc25 A, cyclin A, cyclin B and CDK2 and the up-regulation of p21, p27 and p53. Furthermore, complexes 1 and 2, especially complex 2, acted as telomerase inhibitors targeting c-myc G-quadruplex DNA and triggered cell apoptosis. In addition, 1 and 2 also caused mitochondrial dysfunction. Taken together, we found that 1 and 2 exerted their cytotoxic activity mainly via inhibiting telomerase by interaction with c-myc quadruplex and disruption of mitochondrial function.
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Affiliation(s)
- Hua-Hong Zou
- State Key Laboratory Cultivation Base for The Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, 15 Yucai Road, Guilin 541004, PR China.
| | - Li Wang
- State Key Laboratory Cultivation Base for The Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, 15 Yucai Road, Guilin 541004, PR China
| | - Zhi-Xiang Long
- Guangxi Zhuang Autonomous Region Center for Analysis and Test Research, 32 Xinghu Road, Nanning 530022, PR China
| | - Qi-Pin Qin
- State Key Laboratory Cultivation Base for The Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, 15 Yucai Road, Guilin 541004, PR China
| | - Zhong-Kui Song
- Guangxi Zhuang Autonomous Region Center for Analysis and Test Research, 32 Xinghu Road, Nanning 530022, PR China
| | - Tao Xie
- Guangxi Zhuang Autonomous Region Center for Analysis and Test Research, 32 Xinghu Road, Nanning 530022, PR China
| | - Shu-Hua Zhang
- Guangxi Key Laboratory of Electrochemical and Magnetochemical Functional Materials, College of Chemistry and Bioengineering, Guilin University of Technology, Guilin 541004, PR China
| | - Yan-Cheng Liu
- State Key Laboratory Cultivation Base for The Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, 15 Yucai Road, Guilin 541004, PR China
| | - Bin Lin
- Nanning City No. 2 People's Hospital, 13 Dancun Road, Nanning 530031, PR China
| | - Zhen-Feng Chen
- State Key Laboratory Cultivation Base for The Chemistry and Molecular Engineering of Medicinal Resources, School of Chemistry and Pharmacy, Guangxi Normal University, 15 Yucai Road, Guilin 541004, PR China
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22
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Castor KJ, Metera KL, Tefashe UM, Serpell CJ, Mauzeroll J, Sleiman HF. Cyclometalated Iridium(III) Imidazole Phenanthroline Complexes as Luminescent and Electrochemiluminescent G-Quadruplex DNA Binders. Inorg Chem 2015; 54:6958-67. [PMID: 26125314 DOI: 10.1021/acs.inorgchem.5b00921] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Affiliation(s)
- Katherine J. Castor
- Department of Chemistry, McGill University, 801 Sherbrooke
West, Montreal, Quebec H3A 0B8, Canada
| | - Kimberly L. Metera
- Department of Chemistry, McGill University, 801 Sherbrooke
West, Montreal, Quebec H3A 0B8, Canada
| | - Ushula M. Tefashe
- Department of Chemistry, McGill University, 801 Sherbrooke
West, Montreal, Quebec H3A 0B8, Canada
| | - Christopher J. Serpell
- Department of Chemistry, McGill University, 801 Sherbrooke
West, Montreal, Quebec H3A 0B8, Canada
| | - Janine Mauzeroll
- Department of Chemistry, McGill University, 801 Sherbrooke
West, Montreal, Quebec H3A 0B8, Canada
| | - Hanadi F. Sleiman
- Department of Chemistry, McGill University, 801 Sherbrooke
West, Montreal, Quebec H3A 0B8, Canada
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23
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Skonieczny K, Gryko DT. Photochemical Conversion of Phenanthro[9,10-d]imidazoles into π-Expanded Heterocycles. J Org Chem 2015; 80:5753-63. [DOI: 10.1021/acs.joc.5b00714] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Kamil Skonieczny
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
| | - Daniel T. Gryko
- Institute of Organic Chemistry, Polish Academy of Sciences, Kasprzaka 44/52, 01-224 Warsaw, Poland
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24
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Wei D, Husby J, Neidle S. Flexibility and structural conservation in a c-KIT G-quadruplex. Nucleic Acids Res 2014; 43:629-44. [PMID: 25452341 PMCID: PMC4288176 DOI: 10.1093/nar/gku1282] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
A quadruplex sequence from the promoter region of the c-KIT gene forms a stable quadruplex, as characterized by crystallographic and NMR methods. Two new crystal structures are reported here, together with molecular dynamics simulation studies on these quadruplex crystal structures and an NMR structure. The new crystal structures, each in a distinct space group and lattice packing arrangement, together with the existing structures, demonstrate that the c-KIT quadruplex fold does not change with differing environments, suggesting that quadruplex topological dynamism is not a general phenomenon. The single and dinucleotide loops in these structures show a high degree of conformational flexibility within the three crystal forms and the NMR ensemble, with no evidence of clustering to particular conformers. This is in accord with the findings of high loop flexibility from the molecular dynamics studies. It is suggested that intramolecular quadruplexes can be grouped into two broad classes (i) those with at least one single-nucleotide loop, often showing singular topologies even though loops are highly flexible, and (ii) with all loops comprising at least two nucleotides, leading to topological dynamism. The loops can have more stable and less dynamic base-stacked secondary structures.
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Affiliation(s)
- Dengguo Wei
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
| | - Jarmila Husby
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
| | - Stephen Neidle
- UCL School of Pharmacy, University College London, London WC1N 1AX, UK
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25
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Sequencing and G-quadruplex folding of the canine proto-oncogene KIT promoter region: might dog be used as a model for human disease? PLoS One 2014; 9:e103876. [PMID: 25084283 PMCID: PMC4118953 DOI: 10.1371/journal.pone.0103876] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 07/03/2014] [Indexed: 12/05/2022] Open
Abstract
Downregulation of gene expression by induction of non-canonical DNA structures at promotorial level is a novel attractive anticancer strategy. In human, two guanine-rich sequences (h_kit1 and h_kit2) were identified in the promotorial region of oncogene KIT. Their stabilization into G-quadruplex structures can find applications in the treatment of leukemias, mastocytosis, gastrointestinal stromal tumor, and lung carcinomas which are often associated to c-kit mis-regulation. Also the most common skin cancer in domestic dog, mast cell tumor, is linked to a mutation and/or to an over-expression of c-kit, thus supporting dog as an excellent animal model. In order to assess if the G-quadruplex mediated mechanism of regulation of c-kit expression is conserved among the two species, herein we cloned and sequenced the canine KIT promoter region and we compared it with the human one in terms of sequence and conformational equilibria in physiologically relevant conditions. Our results evidenced a general conserved promotorial sequence between the two species. As experimentally confirmed, this grants that the conformational features of the canine kit1 sequence are substantially shared with the human one. Conversely, two isoforms of the kit2 sequences were identified in the analyzed dog population. In comparison with the human counterpart, both of them showed an altered distribution among several folded conformations.
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