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Li W, Xu H, Zhang H, Wei F, Huang L, Ke S, Fu J, Jing C, Cheng J, Liu S. Tuning electron delocalization of hydrogen-bonded organic framework cathode for high-performance zinc-organic batteries. Nat Commun 2023; 14:5235. [PMID: 37640714 PMCID: PMC10462634 DOI: 10.1038/s41467-023-40969-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 08/18/2023] [Indexed: 08/31/2023] Open
Abstract
Stable cathodes with multiple redox-active centres affording a high energy density, fast redox kinetics and a long life are continuous pursuits for aqueous zinc-organic batteries. Here, we achieve a high-performance zinc-organic battery by tuning the electron delocalization within a designed fully conjugated two-dimensional hydrogen-bonded organic framework as a cathode material. Notably, the intermolecular hydrogen bonds endow this framework with a transverse two-dimensional extended stacking network and structural stability, whereas the multiple C = O and C = N electroactive centres cooperatively trigger multielectron redox chemistry with super delocalization, thereby sharply boosting the redox potential, intrinsic electronic conductivity and redox kinetics. Further mechanistic investigations reveal that the fully conjugated molecular configuration enables reversible Zn2+/H+ synergistic storage accompanied by 10-electron transfer. Benefitting from the above synergistic effects, the elaborately tailored organic cathode delivers a reversible capacity of 498.6 mAh g-1 at 0.2 A g-1, good cyclability and a high energy density (355 Wh kg-1).
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Affiliation(s)
- Wenda Li
- State Key Laboratory of Precision Spectroscopy; Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), School of Physics and Electronic Science, East China Normal University, Shanghai, 200241, P.R. China
| | - Hengyue Xu
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen, 518055, P.R. China
| | - Hongyi Zhang
- State Key Laboratory of Precision Spectroscopy; Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), School of Physics and Electronic Science, East China Normal University, Shanghai, 200241, P.R. China
| | - Facai Wei
- State Key Laboratory of Precision Spectroscopy; Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), School of Physics and Electronic Science, East China Normal University, Shanghai, 200241, P.R. China
| | - Lingyan Huang
- State Key Laboratory of Precision Spectroscopy; Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), School of Physics and Electronic Science, East China Normal University, Shanghai, 200241, P.R. China
| | - Shanzhe Ke
- State Key Laboratory of Precision Spectroscopy; Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), School of Physics and Electronic Science, East China Normal University, Shanghai, 200241, P.R. China
| | - Jianwei Fu
- School of Materials Science and Engineering, Zhengzhou University, 75 Daxue Road, Zhengzhou, 450052, P. R. China
| | - Chengbin Jing
- State Key Laboratory of Precision Spectroscopy; Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), School of Physics and Electronic Science, East China Normal University, Shanghai, 200241, P.R. China
| | - Jiangong Cheng
- State Key Lab of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai, 200050, P. R. China
| | - Shaohua Liu
- State Key Laboratory of Precision Spectroscopy; Engineering Research Center of Nanophotonics & Advanced Instrument (Ministry of Education), School of Physics and Electronic Science, East China Normal University, Shanghai, 200241, P.R. China.
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2
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Chen Z, Wang J, Cai T, Hu Z, Chu J, Wang F, Gan X, Song Z. Constructing Extended π-Conjugated Molecules with o-Quinone Groups as High-Energy Organic Cathode Materials. ACS APPLIED MATERIALS & INTERFACES 2022; 14:27994-28003. [PMID: 35695375 DOI: 10.1021/acsami.2c06252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Although organic cathode materials with sustainability and structural designability have great potential for rechargeable lithium batteries, the dissolution issue presents a huge challenge to meet the demands of cycling stability and energy density simultaneously. Herein, we have designed and successfully synthesized two novel small-molecule organic cathode materials (SMOCMs) by the same innovative route, namely 7,14-diazabenzo[a]tetracene-5,6,8,13-tetraone (DABTTO) and 7,9,16,18-tetraazadibenzo[a,l]pentacene-5,6,8,14,15,17-hexaone (TADBPHO). The integrated p-quinone, o-quinone, and pyrazine groups provide these SMOCMs with attractive theoretical capacities of 473 and 568 mAh g-1 based on 6- and 10-electron reactions, respectively, which were almost fully utilized within 0.8-3.8 V vs Li+/Li. The extended aromatic nucleus of TADBPHO makes it much less soluble than DABTTO and thus able to achieve the highest level of cycling stability (66% @ 500th cycle) for SMOCMs in addition to the exceptional energy density (364 mAh g-1 × 2.56 V = 932 Wh kg-1) within 1.5-3.8 V. In addition to the excellent electrochemical performance, the redox reaction and capacity fading mechanisms have been also investigated in detail. The novel approach to construct extended π-conjugated molecules with o-quinone groups is enlightening for the development of high-energy and stable OCMs for future efficient and sustainable energy storage devices.
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Affiliation(s)
- Zugui Chen
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Junxiao Wang
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Taotao Cai
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Zijun Hu
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Jun Chu
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Feng Wang
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Xiaotang Gan
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Zhiping Song
- Hubei Key Lab of Electrochemical Power Sources, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
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3
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Anti-metastasis and anti-proliferation effect of mitochondria-accumulating ruthenium(II) complexes via redox homeostasis disturbance and energy depletion. J Inorg Biochem 2021; 217:111380. [PMID: 33578250 DOI: 10.1016/j.jinorgbio.2021.111380] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 01/22/2021] [Accepted: 01/23/2021] [Indexed: 01/10/2023]
Abstract
The antiproliferative activity of three cyclometalated Ru(II) complexes with the formula [Ru(bpy)2L]PF6, where bpy = 2,2'-bipyridine, Ru1: L1 = phenanthro[4,5-fgh]quinoxaline; Ru2: L2 = benzo[f]naphtho[2,1-h]quinoxaline; and Ru3: L3 = phenanthro[9,10-b]pyrazine, have been synthesized and characterized. The lipophilicity of the three Ru(II) complexes was modulated by the alteration of the planarity in the ligands of the complexes. With appropriate lipophilicity, Ru1-Ru3 exhibited mitochondrial accumulating property and cytotoxic activity against a spectrum of cancer cell lines. The underlying mechanism study indicated that these Ru(II) complexes can selectively accumulate in mitochondria and disrupt physiological processes, including the redox balance and energy generation in cancer cells. Elevation of iron content in triple-negative breast cancer (MDA-MB-231 cells) was observed after treatment with Ru(II) complexes, which may contribute to the production of reactive oxygen species (ROS) via Fenton reaction chemistry. Besides, the Ru(II) complexes decreased the intracellular glutathione (GSH) in cancer cells, leading to the failure in the cells to combat oxidative damage. Both of the mentioned processes contribute to the high oxidative stress and eventually lead to cancer cell death. On the other hand, Ru1-Ru3 significantly induced the depletion of adenosine triphosphate (ATP), causing disturbance of energy generation. Moreover, the results of wound-healing assay and transwell invasion assay, as well as the tube formation assay indicated the anti-migration and anti-angiogenesis properties of Ru1-Ru3. Our study demonstrated that these Ru(II) complexes are promising chemotherapeutic agents with oxidative stress induction and energy generation disturbance.
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4
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Label-free sensing of abasic DNA using pyrenylamido triazolyl aromatic amino acid scaffold as AIE probe. J Photochem Photobiol A Chem 2020. [DOI: 10.1016/j.jphotochem.2019.112186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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5
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Boyle KM, Barton JK. A Family of Rhodium Complexes with Selective Toxicity toward Mismatch Repair-Deficient Cancers. J Am Chem Soc 2018; 140:5612-5624. [PMID: 29620877 DOI: 10.1021/jacs.8b02271] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Rhodium metalloinsertors are a unique set of metal complexes that bind specifically to DNA base pair mismatches in vitro and kill mismatch repair (MMR)-deficient cells at lower concentrations than their MMR-proficient counterparts. A family of metalloinsertors containing rhodium-oxygen ligand coordination, termed "Rh-O" metalloinsertors, has been prepared and shown to have a significant increase in both overall potency and selectivity toward MMR-deficient cells regardless of structural changes in the ancillary ligands. Here we describe DNA-binding and cellular studies with the second generation of Rh-O metalloinsertors in which an ancillary ligand is varied in both steric bulk and lipophilicity. These complexes, of the form [Rh(L)(chrysi)(PPO)]2+, all include the O-containing PPO ligand (PPO = 2-(pyridine-2-yl)propan-2-ol) and the aromatic inserting ligand chrysi (5,6-chrysene quinone diimine) but differ in the identity of their ancillary ligand L, where L is a phenanthroline or bipyridyl derivative. The Rh-O metalloinsertors in this family all show micromolar binding affinities for a 29-mer DNA hairpin containing a single CC mismatch. The complexes display comparable lipophilic tendencies and p Ka values of 8.1-9.1 for dissociation of an imine proton on the chrysi ligand. In cellular proliferation and cytotoxicity assays with MMR-deficient cells (HCT116O) and MMR-proficient cells (HCT116N), the complexes containing the phenanthroline-derived ligands show highly selective cytotoxic preference for the MMR-deficient cells at nanomolar concentrations. Using mass spectral analyses, it is shown that the complexes are taken into cells through a passive mechanism and exhibit low accumulation in mitochondria, an off-target organelle that, when targeted by parent metalloinsertors, can lead to nonselective cytotoxicity. Overall, these Rh-O metalloinsertors have distinct and improved behavior compared to previous generations of parent metalloinsertors, making them ideal candidates for further therapeutic assessment.
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Affiliation(s)
- Kelsey M Boyle
- Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States
| | - Jacqueline K Barton
- Division of Chemistry and Chemical Engineering , California Institute of Technology , Pasadena , California 91125 , United States
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6
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Gu LQ, Gates KS, Wang MX, Li G. What is the potential of nanolock- and nanocross-nanopore technology in cancer diagnosis? Expert Rev Mol Diagn 2017; 18:113-117. [PMID: 29171309 DOI: 10.1080/14737159.2018.1410060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Li-Qun Gu
- a Department of Bioengineering and Dalton Cardiovascular Research Center , University of Missouri , Columbia , MO , USA
| | - Kent S Gates
- b Department of Chemistry and Department of Biochemistry , University of Missouri , Columbia , MO , USA
| | - Michael X Wang
- c Department of Pathology and Immunology , Washington University School of Medicine , St. Louis , MO , USA
| | - Guangfu Li
- d Department of Surgery and Ellis Fischel Cancer Center , University of Missouri , Columbia , MO , USA
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7
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Wang Y, Tian K, Shi R, Gu A, Pennella M, Alberts L, Gates KS, Li G, Fan H, Wang MX, Gu LQ. Nanolock-Nanopore Facilitated Digital Diagnostics of Cancer Driver Mutation in Tumor Tissue. ACS Sens 2017; 2:975-981. [PMID: 28750524 DOI: 10.1021/acssensors.7b00235] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Cancer driver mutations are clinically significant biomarkers. In precision medicine, accurate detection of these oncogenic changes in patients would enable early diagnostics of cancer, individually tailored targeted therapy, and precise monitoring of treatment response. Here we investigated a novel nanolock-nanopore method for single-molecule detection of a serine/threonine protein kinase gene BRAF V600E mutation in tumor tissues of thyroid cancer patients. The method lies in a noncovalent, mutation sequence-specific nanolock. We found that the nanolock formed on the mutant allele/probe duplex can separate the duplex dehybridization procedure into two sequential steps in the nanopore. Remarkably, this stepwise unzipping kinetics can produce a unique nanopore electric marker, with which a single DNA molecule of the cancer mutant allele can be unmistakably identified in various backgrounds of the normal wild-type allele. The single-molecule sensitivity for mutant allele enables both binary diagnostics and quantitative analysis of mutation occurrence. In the current configuration, the method can detect the BRAF V600E mutant DNA lower than 1% in the tumor tissues. The nanolock-nanopore method can be adapted to detect a broad spectrum of both transversion and transition DNA mutations, with applications from diagnostics to targeted therapy.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Hongxin Fan
- Department
of Pathology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78229, United States
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8
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Deraedt Q, Marcélis L, Loiseau F, Elias B. Towards mismatched DNA photoprobes and photoreagents: “elbow-shaped” Ru(ii) complexes. Inorg Chem Front 2017. [DOI: 10.1039/c6qi00223d] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Due to their potentially harmful consequences, the detection of mismatched DNA is a subject of high interest. In order to probe these DNA mismatches, we report new Ru(ii) complexes, bearing “elbow-shaped” extended planar ligands based on an acridine or a phenazine core.
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Affiliation(s)
- Q. Deraedt
- Institute of Condensed Matter and Nanosciences
- Molecules
- Solids and Reactivity (IMCN/MOST)
- Université catholique de Louvain
- 1348 Louvain-la-Neuve
| | - L. Marcélis
- Institute of Condensed Matter and Nanosciences
- Molecules
- Solids and Reactivity (IMCN/MOST)
- Université catholique de Louvain
- 1348 Louvain-la-Neuve
| | - F. Loiseau
- Département de Chimie Moléculaire
- Université Grenoble-Alpes
- BP53 38041 Grenoble
- France
| | - B. Elias
- Institute of Condensed Matter and Nanosciences
- Molecules
- Solids and Reactivity (IMCN/MOST)
- Université catholique de Louvain
- 1348 Louvain-la-Neuve
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9
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Lee W, Chen Q, Fan X, Yoon DK. Digital DNA detection based on a compact optofluidic laser with ultra-low sample consumption. LAB ON A CHIP 2016; 16:4770-4776. [PMID: 27868127 PMCID: PMC5137248 DOI: 10.1039/c6lc01258b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
DNA lasers self-amplify optical signals from a DNA analyte as well as thermodynamic differences between sequences, allowing quasi-digital DNA detection. However, these systems have drawbacks, such as relatively large sample consumption and complicated dye labelling. Moreover, although the lasing signal can detect the target DNA, it is superimposed on an unintended fluorescence background, which persists for non-target DNA samples as well. From an optical point of view, it is thus not truly digital detection and requires spectral analysis to identify the target. In this work, we propose and demonstrate an optofluidic laser that has a single layer of DNA molecules as the gain material. A target DNA produces intensive laser emission comparable to existing DNA lasers, while any unnecessary fluorescence background is successfully suppressed. As a result, the target DNA can be detected with a single laser pulse, in a truly digital manner. Since the DNA molecules cover only a single layer on the surface of the laser microcavity, the DNA sample consumption is a few orders of magnitude lower than that of existing DNA lasers. Furthermore, the DNA molecules are stained by simply immersing the microcavity in the intercalating dye solution, and thus the proposed DNA laser is free of any complex dye-labelling process prior to analysis.
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Affiliation(s)
- Wonsuk Lee
- Graduate School of Nanoscience and Technology and KINC, KAIST, Daejeon, 305-701, Republic of Korea.
| | - Qiushu Chen
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Ave., Ann Arbor, MI 48109, USA.
| | - Xudong Fan
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Ave., Ann Arbor, MI 48109, USA.
| | - Dong Ki Yoon
- Graduate School of Nanoscience and Technology and KINC, KAIST, Daejeon, 305-701, Republic of Korea.
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10
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Kotera N, Granzhan A, Teulade-Fichou MP. Comparative study of affinity and selectivity of ligands targeting abasic and mismatch sites in DNA using a fluorescence-melting assay. Biochimie 2016; 128-129:133-7. [PMID: 27523781 DOI: 10.1016/j.biochi.2016.08.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 08/08/2016] [Indexed: 11/29/2022]
Abstract
Recently, several families of small-molecule ligands have been developed to selectively target DNA pairing defects, such as abasic sites and mismatched base pairs, with the aim to interfere with the DNA repair and the template function of the DNA. However, the affinity and selectivity (with respect to well-matched DNA) of these ligands has barely been evaluated in a systematic way. Herein, we report a comparative study of binding affinity and selectivity of a representative panel of 16 ligands targeting abasic sites and a T-T mismatch in DNA, using a fluorescence-monitored melting assay. We demonstrate that bisintercalator-type macrocyclic ligands are characterized by moderate affinity but exceptionally high selectivity with respect to well-matched DNA, whereas other reported ligands show either modest selectivity or rather low affinity in identical conditions.
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Affiliation(s)
- Naoko Kotera
- Institut Curie, PSL Research University, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France
| | - Anton Granzhan
- Institut Curie, PSL Research University, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France.
| | - Marie-Paule Teulade-Fichou
- Institut Curie, PSL Research University, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France; Université Paris Sud, Université Paris-Saclay, CNRS UMR9187, INSERM U1196, F-91405, Orsay, France
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11
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Abstract
DNA has been exploited as a biological target of chemotherapeutics since the 1940s. Traditional chemotherapeutics, such as cisplatin and DNA-alkylating agents, rely primarily on increased uptake by rapidly proliferating cancer cells for therapeutic effects, but this strategy can result in off-target toxicity in healthy tissue. Recently, research interests have shifted towards targeted chemotherapeutics, in which a drug targets a specific biological signature of cancer, resulting in selective toxicity towards cancerous cells. Here, we review a family of complexes, termed rhodium metalloinsertors, that selectively target DNA base pair mismatches, a hallmark of mismatch-repair (MMR) deficient cancers. These rhodium metalloinsertors, bind DNA mismatches with high specificity and display high selectively in killing MMR-deficient versus MMR-proficient cells. This cell selectivity is unique for small molecules that bind DNA. Current generations of rhodium metalloinsertors have shown nanomolar potency along with high selectivity towards MMR-deficient cells, and show promise as a foundation for a new family of chemotherapeutics for MMR-deficient cancers.
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Affiliation(s)
- Kelsey M Boyle
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125
| | - Jacqueline K Barton
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125
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12
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Komor AC, Barton JK. An unusual ligand coordination gives rise to a new family of rhodium metalloinsertors with improved selectivity and potency. J Am Chem Soc 2014; 136:14160-72. [PMID: 25254630 PMCID: PMC4195389 DOI: 10.1021/ja5072064] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
![]()
Rhodium
metalloinsertors are octahedral complexes that bind DNA
mismatches with high affinity and specificity and exhibit unique cell-selective
cytotoxicity, targeting mismatch repair (MMR)-deficient cells over
MMR-proficient cells. Here we describe a new generation of metalloinsertors
with enhanced biological potency and selectivity, in which the complexes
show Rh–O coordination. In particular, it has been found that
both Δ- and Λ-[Rh(chrysi)(phen)(DPE)]2+ (where
chrysi =5,6 chrysenequinone diimmine, phen =1,10-phenanthroline, and
DPE = 1,1-di(pyridine-2-yl)ethan-1-ol) bind to DNA containing a single
CC mismatch with similar affinities and without racemization. This
is in direct contrast with previous metalloinsertors and suggests
a possible different binding disposition for these complexes in the
mismatch site. We ascribe this difference to the higher pKa of the coordinated immine of the chrysi ligand in these
complexes, so that the complexes must insert into the DNA helix with
the inserting ligand in a buckled orientation; spectroscopic studies
in the presence and absence of DNA along with the crystal structure
of the complex without DNA support this assignment. Remarkably, all
members of this new family of compounds have significantly increased
potency in a range of cellular assays; indeed, all are more potent
than cisplatin and N-methyl-N′-nitro-nitrosoguanidine
(MNNG, a common DNA-alkylating chemotherapeutic agent). Moreover,
the activities of the new metalloinsertors are coupled with high levels
of selective cytotoxicity for MMR-deficient versus proficient colorectal
cancer cells.
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Affiliation(s)
- Alexis C Komor
- Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena California 91125, United States
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13
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Franco D, Vargiu AV, Magistrato A. Ru[(bpy)2(dppz)]2+ and Rh[(bpy)2(chrysi)]3+ Targeting Double Strand DNA: The Shape of the Intercalating Ligand Tunes the Free Energy Landscape of Deintercalation. Inorg Chem 2014; 53:7999-8008. [DOI: 10.1021/ic5008523] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Duvan Franco
- International School for Advanced Studies (SISSA/ISAS), via Bonomea 265, 34136, Trieste, Italy
| | - Attilio V. Vargiu
- Dipartimento
di Fisica, Università di Cagliari, s.p. Monserrato-Sestu km 0.700, I-09042 Monserrato, Italy
| | - Alessandra Magistrato
- CNR-IOM-DEMOCRITOS c/o International School for Advanced Studies (SISSA/ISAS), via Bonomea 265, 34136, Trieste, Italy
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14
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Abstract
Transcription factor p53 is the most commonly altered gene in human cancer. As a redox-active protein in direct contact with DNA, p53 can directly sense oxidative stress through DNA-mediated charge transport. Electron hole transport occurs over long distances through the π-stacked bases and leads to the oxidative dissociation of p53. The extent of protein dissociation depends upon the redox potential of the DNA in direct contact with each p53 monomer. The DNA sequence dependence of p53 oxidative dissociation was examined by electrophoretic mobility shift assays using oligonucleotides containing both synthetic and human p53 consensus sequences with an appended photooxidant, anthraquinone. Greater p53 dissociation is observed from sequences containing low-redox potential purine regions, particularly guanine triplets. Using denaturing polyacrylamide gel electrophoresis of irradiated anthraquinone-modified DNA, the DNA damage sites corresponding to sites of preferred electron hole localization were determined. The resulting DNA damage preferentially localizes to guanine doublets and triplets. Oxidative DNA damage is inhibited in the presence of p53, but only at sites in direct contact with p53. From these data, predictions about the sensitivity of human p53-binding sites to oxidative stress as well as possible biological implications have been made. On the basis of our data, the guanine pattern within the purine region of each p53-binding site determines the response of p53 to DNA oxidation, yielding for some sequences the oxidative dissociation of p53 from a distance and thereby providing another potential role for DNA charge transport chemistry within the cell.
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Affiliation(s)
- Kathryn N Schaefer
- Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
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15
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Granzhan A, Kotera N, Teulade-Fichou MP. Finding needles in a basestack: recognition of mismatched base pairs in DNA by small molecules. Chem Soc Rev 2014; 43:3630-65. [DOI: 10.1039/c3cs60455a] [Citation(s) in RCA: 84] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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16
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Weidmann AG, Komor AC, Barton JK. Biological effects of simple changes in functionality on rhodium metalloinsertors. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2013; 371:20120117. [PMID: 23776288 PMCID: PMC3685451 DOI: 10.1098/rsta.2012.0117] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
DNA mismatch repair (MMR) is crucial to ensuring the fidelity of the genome. The inability to correct single base mismatches leads to elevated mutation rates and carcinogenesis. Using metalloinsertors-bulky metal complexes that bind with high specificity to mismatched sites in the DNA duplex-our laboratory has adopted a new chemotherapeutic strategy through the selective targeting of MMR-deficient cells, that is, those that have a propensity for cancerous transformation. Rhodium metalloinsertors display inhibitory effects selectively in cells that are deficient in the MMR machinery, consistent with this strategy. However, a highly sensitive structure-function relationship is emerging with the development of new complexes that highlights the importance of subcellular localization. We have found that small structural modifications, for example a hydroxyl versus a methyl functional group, can yield profound differences in biological function. Despite similar binding affinities and selectivities for DNA mismatches, only one metalloinsertor shows selective inhibition of cellular proliferation in MMR-deficient versus -proficient cells. Studies of whole-cell, nuclear and mitochondrial uptake reveal that this selectivity depends upon targeting DNA mismatches in the cell nucleus.
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17
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Smith NA, Sadler PJ. Photoactivatable metal complexes: from theory to applications in biotechnology and medicine. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2013; 371:20120519. [PMID: 23776303 PMCID: PMC3685452 DOI: 10.1098/rsta.2012.0519] [Citation(s) in RCA: 128] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
This short review highlights some of the exciting new experimental and theoretical developments in the field of photoactivatable metal complexes and their applications in biotechnology and medicine. The examples chosen are based on some of the presentations at the Royal Society Discussion Meeting in June 2012, many of which are featured in more detail in other articles in this issue. This is a young field. Even the photochemistry of well-known systems such as metal-carbonyl complexes is still being elucidated. Striking are the recent developments in theory and computation (e.g. time-dependent density functional theory) and in ultrafast-pulsed radiation techniques which allow photochemical reactions to be followed and their mechanisms to be revealed on picosecond/nanosecond time scales. Not only do some metal complexes (e.g. those of Ru and Ir) possess favourable emission properties which allow functional imaging of cells and tissues (e.g. DNA interactions), but metal complexes can also provide spatially controlled photorelease of bioactive small molecules (e.g. CO and NO)--a novel strategy for site-directed therapy. This extends to cancer therapy, where metal-based precursors offer the prospect of generating excited-state drugs with new mechanisms of action that complement and augment those of current organic photosensitizers.
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Bag SS, Kundu R, Jana S. Sensing of biomolecules and label-free discrimination of DNA containing a triple T–C/T–G mismatch pair with a fluorescence light-up probe, triazolylpyrene (TNDMBPy). Tetrahedron Lett 2013. [DOI: 10.1016/j.tetlet.2013.03.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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SATO Y, KAGEYAMA T, NISHIZAWA S, TERAMAE N. Competitive Binding of Abasic Site-Binding Ligands and Masking Ligands to DNA Duplexes for the Analysis of Single-Base Mutation. ANAL SCI 2013; 29:15-9. [DOI: 10.2116/analsci.29.15] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Yusuke SATO
- Department of Chemistry, Graduate School of Science, Tohoku University
| | - Tomoe KAGEYAMA
- Department of Chemistry, Graduate School of Science, Tohoku University
| | - Seiichi NISHIZAWA
- Department of Chemistry, Graduate School of Science, Tohoku University
| | - Norio TERAMAE
- Department of Chemistry, Graduate School of Science, Tohoku University
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Komor AC, Schneider CJ, Weidmann AG, Barton JK. Cell-selective biological activity of rhodium metalloinsertors correlates with subcellular localization. J Am Chem Soc 2012; 134:19223-33. [PMID: 23137296 PMCID: PMC3740518 DOI: 10.1021/ja3090687] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Deficiencies in the mismatch repair (MMR) pathway are associated with several types of cancers, as well as resistance to commonly used chemotherapeutics. Rhodium metalloinsertors have been found to bind DNA mismatches with high affinity and specificity in vitro, and also exhibit cell-selective cytotoxicity, targeting MMR-deficient cells over MMR-proficient cells. Ten distinct metalloinsertors with varying lipophilicities have been synthesized and their mismatch binding affinities and biological activities determined. Although DNA photocleavage experiments demonstrate that their binding affinities are quite similar, their cell-selective antiproliferative and cytotoxic activities vary significantly. Inductively coupled plasma mass spectrometry (ICP-MS) experiments have uncovered a relationship between the subcellular distribution of these metalloinsertors and their biological activities. Specifically, we find that all of our metalloinsertors localize in the nucleus at sufficient concentrations for binding to DNA mismatches. However, the metalloinsertors with high rhodium localization in the mitochondria show toxicity that is not selective for MMR-deficient cells, whereas metalloinsertors with less mitochondrial rhodium show activity that is highly selective for MMR-deficient versus proficient cells. This work supports the notion that specific targeting of the metalloinsertors to nuclear DNA gives rise to their cell-selective cytotoxic and antiproliferative activities. The selectivity in cellular targeting depends upon binding to mismatches in genomic DNA.
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Affiliation(s)
- Alexis C. Komor
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125
| | - Curtis J. Schneider
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125
| | - Alyson G. Weidmann
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125
| | - Jacqueline K. Barton
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125
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McConnell AJ, Lim MH, Olmon ED, Song H, Dervan EE, Barton JK. Luminescent properties of ruthenium(II) complexes with sterically expansive ligands bound to DNA defects. Inorg Chem 2012; 51:12511-20. [PMID: 23113594 DOI: 10.1021/ic3019524] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
A new family of ruthenium(II) complexes with sterically expansive ligands for targeting DNA defects was prepared, and their luminescent responses to base pair mismatches and/or abasic sites were investigated. Design of the complexes sought to combine the mismatch specificity of sterically expansive metalloinsertors, such as [Rh(bpy)2(chrysi)](3+) (chrysi = chrysene-5,6-quinone diimine), and the light switch behavior of [Ru(bpy)2(dppz)](2+) (dppz = dipyrido[3,2-a:2',3'-c]phenazine). In one approach, complexes bearing analogues of chrysi incorporating hydrogen-bonding functionality similar to dppz were synthesized. While the complexes show luminescence only at low temperatures (77 K), competition experiments with [Ru(bpy)2(dppz)](2+) at ambient temperatures reveal that the chrysi derivatives preferentially bind DNA mismatches. In another approach, various substituents were introduced onto the dppz ligand to increase its steric bulk for mismatch binding while maintaining planarity. Steady state luminescence and luminescence lifetime measurements reveal that these dppz derivative complexes behave as DNA "light switches" but that the selectivity in binding and luminescence with mismatched/abasic versus well-matched DNA is not high. In all cases, luminescence depends sensitively upon structural perturbations to the dppz ligand.
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Affiliation(s)
- Anna J McConnell
- Division of Chemistry and Chemical Engineering, California Institute of Technology , Pasadena, California 91125, United States
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Affiliation(s)
- Wonsuk Lee
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Avenue, Ann Arbor,
Michigan 48109, United States
- Department of Electrical Engineering
and Computer Science, University of Michigan, 1301 Beal Avenue, Ann Arbor, Michigan 48109, United States
| | - Xudong Fan
- Department of Biomedical Engineering, University of Michigan, 1101 Beal Avenue, Ann Arbor,
Michigan 48109, United States
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Ghosh P, Sinan M, Lahiri D, Roy S, Goswami S. Design and Synthesis of a Functional Derivative of the Triazinium Cation and Its Rhodium Complex that Shows Photoinduced DNA Cleavage Activity and Photocytotoxicity. Eur J Inorg Chem 2012. [DOI: 10.1002/ejic.201200054] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Alubaidy M, Soleymani L, Venkatakrishnan K, Tan B. Femtosecond laser nanostructuring for femtosensitive DNA detection. Biosens Bioelectron 2012; 33:82-7. [DOI: 10.1016/j.bios.2011.12.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2011] [Revised: 11/30/2011] [Accepted: 12/14/2011] [Indexed: 10/14/2022]
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Vargiu AV, Magistrato A. Detecting DNA Mismatches with Metallo-Insertors: A Molecular Simulation Study. Inorg Chem 2012; 51:2046-57. [DOI: 10.1021/ic201659v] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Attilio V. Vargiu
- CNR-IOM, Unità Operativa
di Supporto SLACS, c/o Dipartimento di Fisica, Università di Cagliari, s.p. Monserrato-Sestu km 0.7, I-09042 Monserrato,
Italy
| | - Alessandra Magistrato
- CNR-IOM-Democritos,
National
Simulation Center, c/o International School for Advanced Studies (SISSA/ISAS), via Bonomea 265, 34136, Trieste,
Italy
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Mononuclear copper(II) complex with terpyridine and an extended phenanthroline base, [Cu(tpy)(dppz)]2+: Synthesis, crystal structure, DNA binding and cytotoxicity activity. Polyhedron 2012. [DOI: 10.1016/j.poly.2011.10.028] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Chakravarty AR, Roy M. Photoactivated DNA Cleavage and Anticancer Activity of 3d Metal Complexes. PROGRESS IN INORGANIC CHEMISTRY 2011. [DOI: 10.1002/9781118148235.ch3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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Olmon ED, Hill MG, Barton JK. Using metal complex reduced states to monitor the oxidation of DNA. Inorg Chem 2011; 50:12034-44. [PMID: 22043853 PMCID: PMC3277451 DOI: 10.1021/ic201511y] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Metallointercalating photooxidants interact intimately with the base stack of double-stranded DNA and exhibit rich photophysical and electrochemical properties, making them ideal probes for the study of DNA-mediated charge transport (CT). The complexes [Rh(phi)(2)(bpy')](3+) (phi = 9,10-phenanthrenequinone diimine; bpy' = 4-methyl-4'-(butyric acid)-2,2'-bipyridine), [Ir(ppy)(2)(dppz')](+) (ppy = 2-phenylpyridine; dppz' = 6-(dipyrido[3,2-a:2',3'-c]phenazin-11-yl)hex-5-ynoic acid), and [Re(CO)(3)(dppz)(py')](+) (dppz = dipyrido[2,3-a:2',3'-c]phenazine; py' = 3-(pyridin-4-yl)-propanoic acid) were each covalently tethered to DNA to compare their photooxidation efficiencies. Biochemical studies show that upon irradiation, the three complexes oxidize guanine by long-range DNA-mediated CT with the efficiency: Rh > Re > Ir. Comparison of spectra obtained by spectroelectrochemistry after bulk reduction of the free metal complexes with those obtained by transient absorption (TA) spectroscopy of the conjugates suggests that the reduced metal states form following excitation of the conjugates at 355 nm. Electrochemical experiments and kinetic analysis of the TA decays indicate that the thermodynamic driving force for CT, variations in the efficiency of back electron transfer, and coupling to DNA are the primary factors responsible for the trend observed in the guanine oxidation yields of the three complexes.
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Affiliation(s)
- Eric D. Olmon
- Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena, California 91125, USA
| | - Michael G. Hill
- Department of Chemistry, Occidental College, Los Angeles, California 90041, USA
| | - Jacqueline K. Barton
- Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena, California 91125, USA
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Ernst RJ, Komor AC, Barton JK. Selective cytotoxicity of rhodium metalloinsertors in mismatch repair-deficient cells. Biochemistry 2011; 50:10919-28. [PMID: 22103240 DOI: 10.1021/bi2015822] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Mismatches in DNA occur naturally during replication and as a result of endogenous DNA damaging agents, but the mismatch repair (MMR) pathway acts to correct mismatches before subsequent rounds of replication. Rhodium metalloinsertors bind to DNA mismatches with high affinity and specificity and represent a promising strategy to target mismatches in cells. Here we examine the biological fate of rhodium metalloinsertors bearing dipyridylamine ancillary ligands in cells deficient in MMR versus those that are MMR-proficient. These complexes are shown to exhibit accelerated cellular uptake which permits the observation of various cellular responses, including disruption of the cell cycle, monitored by flow cytometry assays, and induction of necrosis, monitored by dye exclusion and caspase inhibition assays, that occur preferentially in the MMR-deficient cell line. These cellular responses provide insight into the mechanisms underlying the selective activity of this novel class of targeted anticancer agents.
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Affiliation(s)
- Russell J Ernst
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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Towards artificial metallonucleases for gene therapy: recent advances and new perspectives. Future Med Chem 2011; 3:1935-66. [DOI: 10.4155/fmc.11.139] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The process of DNA targeting or repair of mutated genes within the cell, induced by specifically positioned double-strand cleavage of DNA near the mutated sequence, can be applied for gene therapy of monogenic diseases. For this purpose, highly specific artificial metallonucleases are developed. They are expected to be important future tools of modern genetics. The present state of art and strategies of research are summarized, including protein engineering and artificial ‘chemical’ nucleases. From the results, we learn about the basic role of the metal ions and the various ligands, and about the DNA binding and cleavage mechanism. The results collected provide useful guidance for engineering highly controlled enzymes for use in gene therapy.
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Palanichamy K, Sreejayan N, Ontko AC. Overcoming cisplatin resistance using gold(III) mimics: anticancer activity of novel gold(III) polypyridyl complexes. J Inorg Biochem 2011; 106:32-42. [PMID: 22112837 DOI: 10.1016/j.jinorgbio.2011.08.013] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Revised: 08/18/2011] [Accepted: 08/19/2011] [Indexed: 11/27/2022]
Abstract
Gold(III) compounds have been recognized as anticancer agents due to their structural and electronic similarities with currently employed platinum(II) species. An added benefit to gold(III) agents is the ability to overcome cisplatin resistance. This work identified four gold(III) compounds, [Au(Phen)Cl(2)]PF(6), [Au(DPQ)Cl(2)]PF(6), [Au(DPPZ)Cl(2)]PF(6), and [Au(DPQC)Cl(2)]PF(6), (Phen = 1,10-phenanthroline, DPQ = dipyrido[3,2-d:2',3'-f]quinoxaline, DPPZ = dipyrido[3,2-a:2',3'-c] phenazine, DPQC = dipyrido[3,2-d:2',3'-f] cyclohexyl quinoxaline) that exhibited anticancer activity in both cisplatin sensitive and cisplatin resistant ovarian cancer cells. Two of these compounds, [Au(DPQ)Cl(2)]PF(6) (AQ) and [Au(DPPZ)Cl(2)]PF(6) (AZ), displayed exceptional anticancer activity and were the focus of more intensive mechanistic study. At the molecular level, AQ and AZ formed DNA adducts, generated free radicals, and upregulated pro-apoptotic signaling molecules (p53, caspases, PARP, death effectors). Taken together, these two novel gold(III) polypyridyl complexes exhibit potent antitumor activity in cisplatin resistant cancer cells. These activities may be mediated, in part, by the activation of apoptotic signaling.
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Affiliation(s)
- Kamalakannan Palanichamy
- Department of Radiation Oncology, The Ohio State University Medical Center, Columbus, OH 43210, USA
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32
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Olmon ED, Sontz PA, Blanco-Rodríguez AM, Towrie M, Clark IP, Vlček A, Barton JK. Charge photoinjection in intercalated and covalently bound [Re(CO)3(dppz)(py)]+-DNA constructs monitored by time-resolved visible and infrared spectroscopy. J Am Chem Soc 2011; 133:13718-30. [PMID: 21827149 PMCID: PMC3227519 DOI: 10.1021/ja205568r] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The complex [Re(CO)(3)(dppz)(py'-OR)](+) (dppz = dipyrido[3,2-a:2',3'-c]phenazine; py'-OR = 4-functionalized pyridine) offers IR sensitivity and can oxidize DNA directly from the excited state, making it a promising probe for the study of DNA-mediated charge transport (CT). The behavior of several covalent and noncovalent Re-DNA constructs was monitored by time-resolved IR (TRIR) and UV/visible spectroscopies, as well as biochemical methods, confirming the long-range oxidation of DNA by the excited complex. Optical excitation of the complex leads to population of MLCT and at least two distinct intraligand states. Experimental observations that are consistent with charge injection from these excited states include similarity between long-time TRIR spectra and the reduced state spectrum observed by spectroelectrochemistry, the appearance of a guanine radical signal in TRIR spectra, and the eventual formation of permanent guanine oxidation products. The majority of reactivity occurs on the ultrafast time scale, although processes dependent on slower conformational motions of DNA, such as the accumulation of oxidative damage at guanine, are also observed. The ability to measure events on such disparate time scales, its superior selectivity in comparison to other spectroscopic techniques, and the ability to simultaneously monitor carbonyl ligand and DNA IR absorption bands make TRIR a valuable tool for the study of CT in DNA.
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Affiliation(s)
- Eric D Olmon
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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Spencer BR, Kraft BJ, Hughes CG, Pink M, Zaleski JM. Modulating the Light Switch by 3MLCT-3ππ* State Interconversion. Inorg Chem 2010; 49:11333-45. [DOI: 10.1021/ic1011617] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Brigitte R. Spencer
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Brian J. Kraft
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Chris G. Hughes
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Maren Pink
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
| | - Jeffrey M. Zaleski
- Department of Chemistry and Molecular Structure Center, Indiana University, Bloomington, Indiana 47405, United States
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34
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Inorganic nanoparticles in cancer therapy. Pharm Res 2010; 28:237-59. [PMID: 21104301 DOI: 10.1007/s11095-010-0318-0] [Citation(s) in RCA: 213] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2010] [Accepted: 11/01/2010] [Indexed: 01/10/2023]
Abstract
Nanotechnology is an evolving field with enormous potential for biomedical applications. The growing interest to use inorganic nanoparticles in medicine is due to the unique size- and shape-dependent optoelectronic properties. Herein, we will focus on gold, silver and platinum nanoparticles, discussing recent developments for therapeutic applications with regard to cancer in terms of nanoparticles being used as a delivery vehicle as well as therapeutic agents. We will also discuss some of the key challenges to be addressed in future studies.
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Farrer NJ, Salassa L, Sadler PJ. Photoactivated chemotherapy (PACT): the potential of excited-state d-block metals in medicine. Dalton Trans 2009:10690-701. [PMID: 20023896 PMCID: PMC2933824 DOI: 10.1039/b917753a] [Citation(s) in RCA: 379] [Impact Index Per Article: 25.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The fields of phototherapy and of inorganic chemotherapy both have long histories. Inorganic photoactivated chemotherapy (PACT) offers both temporal and spatial control over drug activation and has remarkable potential for the treatment of cancer. Following photoexcitation, a number of different decay pathways (both photophysical and photochemical) are available to a metal complex. These pathways can result in radiative energy release, loss of ligands or transfer of energy to another species, such as triplet oxygen. We discuss the features which need to be considered when developing a metal-based anticancer drug, and the common mechanisms by which the current complexes are believed to operate. We then provide a comprehensive overview of PACT developments for complexes of the different d-block metals for the treatment of cancer, detailing the more established areas concerning Ti, V, Cr, Mn, Re, Fe, Ru, Os, Co, Rh, Pt, and Cu and also highlighting areas where there is potential for greater exploration. Nanoparticles (Ag, Au) and quantum dots (Cd) are also discussed for their photothermal destructive potential. We also discuss the potential held in particular by mixed-metal systems and Ru complexes.
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Affiliation(s)
- Nicola J. Farrer
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | - Luca Salassa
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
| | - Peter J. Sadler
- Department of Chemistry, University of Warwick, Gibbet Hill Road, Coventry, CV4 7AL, UK
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Zeglis BM, Pierre VC, Kaiser JT, Barton JK. A bulky rhodium complex bound to an adenosine-adenosine DNA mismatch: general architecture of the metalloinsertion binding mode. Biochemistry 2009; 48:4247-53. [PMID: 19374348 DOI: 10.1021/bi900194e] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Two crystal structures of Delta-Rh(bpy)(2)(chrysi)(3+) (chrysi is 5,6-chrysenequinone diimine) bound to the oligonucleotide duplex 5'-CGGAAATTACCG-3' containing two adenosine-adenosine mismatches (italics) through metalloinsertion were determined. Diffraction quality crystals with two different space groups (P3(2)21 and P4(3)2(1)2) were obtained under very similar crystallization conditions. In both structures, the bulky rhodium complex inserts into the two mismatched sites from the minor groove side, ejecting the mismatched bases into the major groove. The conformational changes are localized to the mismatched site; the metal complex replaces the mismatched base pair without an increase in base pair rise. The expansive metal complex is accommodated in the duplex by a slight opening in the phosphodiester backbone; all sugars retain a C2'-endo puckering, and flanking base pairs neither stretch nor shear. The structures differ, however, in that in one of the structures, an additional metal complex is bound by intercalation from the major groove at the central 5'-AT-3' step. We conclude that this additional metal complex is intercalated into this central step because of crystal packing forces. The structures described here of Delta-Rh(bpy)(2)(chrysi)(3+) bound to thermodynamically destabilized AA mismatches share critical features with binding by metalloinsertion in two other oligonucleotides containing different single-base mismatches. These results underscore the generality of metalloinsertion as a new mode of noncovalent binding by small molecules with a DNA duplex.
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Affiliation(s)
- Brian M Zeglis
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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37
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Ernst RJ, Song H, Barton JK. DNA mismatch binding and antiproliferative activity of rhodium metalloinsertors. J Am Chem Soc 2009; 131:2359-66. [PMID: 19175313 DOI: 10.1021/ja8081044] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Deficiencies in mismatch repair (MMR) are associated with carcinogenesis. Rhodium metalloinsertors bind to DNA base mismatches with high specificity and inhibit cellular proliferation preferentially in MMR-deficient cells versus MMR-proficient cells. A family of chrysenequinone diimine complexes of rhodium with varying ancillary ligands that serve as DNA metalloinsertors has been synthesized, and both DNA mismatch binding affinities and antiproliferative activities against the human colorectal carcinoma cell lines HCT116N and HCT116O, an isogenic model system for MMR deficiency, have been determined. DNA photocleavage experiments reveal that all complexes bind to the mismatch sites with high specificities; DNA binding affinities to oligonucleotides containing single base CA and CC mismatches, obtained through photocleavage titration or competition, vary from 10(4) to 10(8) M(-1) for the series of complexes. Significantly, binding affinities are found to be inversely related to ancillary ligand size and directly related to differential inhibition of the HCT116 cell lines. The observed trend in binding affinity is consistent with the metalloinsertion mode where the complex binds from the minor groove with ejection of mismatched base pairs. The correlation between binding affinity and targeting of the MMR-deficient cell line suggests that rhodium metalloinsertors exert their selective biological effects on MMR-deficient cells through mismatch binding in vivo.
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Affiliation(s)
- Russell J Ernst
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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Zeglis BM, Boland JA, Barton JK. Recognition of abasic sites and single base bulges in DNA by a metalloinsertor. Biochemistry 2009; 48:839-49. [PMID: 19146409 DOI: 10.1021/bi801885w] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Abasic sites and single base bulges are thermodynamically destabilizing DNA defects that can lead to cancerous transformations if left unrepaired by the cell. Here we discuss the binding properties with abasic sites and single base bulges of Rh(bpy)(2)(chrysi)(3+), a complex previously shown to bind thermodynamically destabilized mismatch sites via metalloinsertion. Photocleavage experiments show that Rh(bpy)(2)(chrysi)(3+) selectively binds abasic sites with affinities of 1-4 x 10(6) M(-1); specific binding is independent of unpaired base identity but is somewhat contingent on sequence context. Single base bulges are also selectively bound and cleaved, but in this case, the association constants are significantly lower ( approximately 10(5) M(-1)), and the binding is dependent on both unpaired base identity and bulge sequence context. A wide variety of evidence, including strand scission asymmetry, binding enantiospecificity, and MALDI-TOF cleavage fragment analysis, suggests that Rh(bpy)(2)(chrysi)(3+) binds abasic sites, like mismatches, through insertion of the bulky chrysi ligand into the base pair stack from the minor groove side and ejection of the unpaired base. At single base bulge sites, a similar, though not identical, metalloinsertion mode is suggested. The recognition of abasic sites and single base bulges with bulky metalloinsertors holds promise for diagnostic and therapeutic applications.
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Affiliation(s)
- Brian M Zeglis
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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Fang Z, Kelley SO. Direct electrocatalytic mRNA detection using PNA-nanowire sensors. Anal Chem 2009; 81:612-7. [PMID: 19086897 DOI: 10.1021/ac801890f] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We report an electrochemical nucleic acids sensing system that exhibits high sensitivity and specificity when challenged with heterogeneous samples of RNA. The platform directly detects specific RNA sequences in cellular and clinical samples without any sample labeling or PCR amplification. The sensor features an electrode platform consisting of three-dimensional gold nanowires, and DNA or RNA hybridization is detected using an electrocatalytic reporter system. In this study, probes made of peptide nucleic acid (PNA) are used to detect a newly identified cancer biomarkera gene fusion recently associated with prostate cancer. The system is able to detect the fusion sequence with 100 fM sensitivity, and retains high sensitivity even in the presence of a large excess of non-complementary sequences. Moreover, the sensor is able to detect the fusion sequence in as little as 10 ng of mRNA isolated from cell lines or 100 ng total RNA from patient tissue samples. The PNA-nanowire nucleic acids sensor described is one of the first electrochemical sensors to directly detect specific mRNAs in unamplified patient samples.
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Affiliation(s)
- Zhichao Fang
- Leslie Dan Faculty of Pharmacy, Department of Pharmaceutical Sciences, and Faculty of Medicine, Department of Biochemistry, University of Toronto, Ontario M5S 3M2, Canada
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Grigorenko N, Leumann C. 2-Phenanthrenyl-DNA: Synthesis, Pairing, and Fluorescence Properties. Chemistry 2009; 15:639-45. [DOI: 10.1002/chem.200801135] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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41
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Bahr M, Gabelica V, Granzhan A, Teulade-Fichou MP, Weinhold E. Selective recognition of pyrimidine-pyrimidine DNA mismatches by distance-constrained macrocyclic bis-intercalators. Nucleic Acids Res 2008; 36:5000-12. [PMID: 18658249 PMCID: PMC2528167 DOI: 10.1093/nar/gkn392] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Binding of three macrocyclic bis-intercalators, derivatives of acridine and naphthalene, and two acyclic model compounds to mismatch-containing and matched duplex oligodeoxynucleotides was analyzed by thermal denaturation experiments, electrospray ionization mass spectrometry studies (ESI-MS) and fluorescent intercalator displacement (FID) titrations. The macrocyclic bis-intercalators bind to duplexes containing mismatched thymine bases with high selectivity over the fully matched ones, whereas the acyclic model compounds are much less selective and strongly bind to the matched DNA. Moreover, the results from thermal denaturation experiments are in very good agreement with the binding affinities obtained by ESI-MS and FID measurements. The FID results also demonstrate that the macrocyclic naphthalene derivative BisNP preferentially binds to pyrimidine–pyrimidine mismatches compared to all other possible base mismatches. This ligand also efficiently competes with a DNA enzyme (M.TaqI) for binding to a duplex with a TT-mismatch, as shown by competitive fluorescence titrations. Altogether, our results demonstrate that macrocyclic distance-constrained bis-intercalators are efficient and selective mismatch-binding ligands that can interfere with mismatch-binding enzymes.
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Affiliation(s)
- Matthias Bahr
- Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, D-52056 Aachen, Germany
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Zeglis BM, Barton JK. Binding of Ru(bpy)2(eilatin)2+ to matched and mismatched DNA. Inorg Chem 2008; 47:6452-7. [PMID: 18576614 DOI: 10.1021/ic8006537] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The DNA-binding properties of Ru(bpy)2(eilatin)(2+) have been investigated to determine if the sterically expansive eilatin ligand confers specificity for destabilized single-base mismatches in DNA. Competitive DNA photocleavage experiments employing a sequence-neutral metallointercalator, Rh(bpy)2(phi)(3+) (phi = 9,10-phenanthrenequinonediimine), and a mismatch-specific metalloinsertor, Rh(bpy)2(chrysi)(3+) (chrysi = chrysene-5,6-quinonediimine), reveal that the eilatin complex binds to a CC mismatched site with an apparent binding constant of 2.2(2) x 10(6) M(-1). Nonetheless, the selectivity in binding mismatched DNA is not high: competitive titrations with Rh(bpy)2(phi)(3+) show that the complex binds also to well-matched B-form sites. Thus, Ru(bpy)2(eilatin)(2+), despite containing the extremely expansive eilatin ligand, displays lower selectivity for the mismatch than does Rh(bpy)2(chrysi)(3+), a metalloinsertor containing the smaller, though still bulky, chrysene-5,6-quinonediimine ligand. In summary, the size and shape of the eilatin ligand allow stacking with both well-matched and mismatched DNA.
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Affiliation(s)
- Brian M Zeglis
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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Zeglis BM, Boland JA, Barton JK. Targeting abasic sites and single base bulges in DNA with metalloinsertors. J Am Chem Soc 2008; 130:7530-1. [PMID: 18491905 PMCID: PMC2759749 DOI: 10.1021/ja801479y] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The site-specific recognition of abasic sites and single base bulges in duplex DNA by sterically expansive rhodium metalloinsertors has been investigated. Through DNA photocleavage experiments, Rh(bpy)2(chrysi)3+ is shown to bind both abasic sites and single base bulges site-specifically and, upon irradiation, to cleave the backbone of the defect-containing DNA. Photocleavage titrations reveal that the metal complex binds DNA containing an abasic site with high affinity (2.6(5) x 106 M-1), comparably to the metalloinsertor and a CC mismatch. The complex binds single base bulge sites with lower affinity (approximately 105 M-1). Analysis of cleavage products and the correlation of affinities with helix destabilization suggest that Rh(bpy)2(chrysi)3+ binds both lesions via metalloinsertion, as observed for Rh binding at mismatched sites, a binding mode in which the mismatched or unpaired bases are extruded from the helix and replaced in the base stack by the sterically expansive ligand of the metalloinsertor.
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Affiliation(s)
- Brian M. Zeglis
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Jennifer A. Boland
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
| | - Jacqueline K. Barton
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125
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Kostal V, Katzenmeyer J, Arriaga EA. Capillary electrophoresis in bioanalysis. Anal Chem 2008; 80:4533-50. [PMID: 18484738 DOI: 10.1021/ac8007384] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Vratislav Kostal
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, USA
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Xiong AS, Peng RH, Zhuang J, Gao F, Li Y, Cheng ZM, Yao QH. Chemical gene synthesis: strategies, softwares, error corrections, and applications. FEMS Microbiol Rev 2008; 32:522-40. [DOI: 10.1111/j.1574-6976.2008.00109.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
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Farrer NJ, Sadler PJ. Photochemotherapy: Targeted Activation of Metal Anticancer Complexes. Aust J Chem 2008. [DOI: 10.1071/ch08088] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
The present article highlights recent findings in the field of photoactivation of anticancer metal complexes. Developments of some photoactivatable Rh-, Pt-, and Fe-based complexes are discussed and their mechanisms of anticancer action are outlined. Features required for the successful design of photoactive drugs are considered, in particular methods for improving the targeting and selectivity of such complexes through techniques such as conjugate delivery and multiphoton absorption.
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Abstract
Since the elucidation of the structure of double helical DNA, the construction of small molecules that recognize and react at specific DNA sites has been an area of considerable interest. In particular, the study of transition metal complexes that bind DNA with specificity has been a burgeoning field. This growth has been due in large part to the useful properties of metal complexes, which possess a wide array of photophysical attributes and allow for the modular assembly of an ensemble of recognition elements. Here we review recent experiments in our laboratory aimed at the design and study of octahedral metal complexes that bind DNA non-covalently and target reactions to specific sites. Emphasis is placed both on the variety of methods employed to confer site-specificity and upon the many applications for these complexes. Particular attention is given to the family of complexes recently designed that target single base mismatches in duplex DNA through metallo-insertion.
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Affiliation(s)
- Brian M. Zeglis
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125 USA Fax: 626-577-4976; Tel: 626-395-6075; E-mail:
| | - Valerie C. Pierre
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125 USA Fax: 626-577-4976; Tel: 626-395-6075; E-mail:
| | - Jacqueline K. Barton
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena CA 91125 USA Fax: 626-577-4976; Tel: 626-395-6075; E-mail:
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Lim MH, Lau IH, Barton JK. DNA strand cleavage near a CC mismatch directed by a metalloinsertor. Inorg Chem 2007; 46:9528-30. [PMID: 17918931 PMCID: PMC2747586 DOI: 10.1021/ic701598k] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Reagents for recognition and efficient cleavage of mismatched DNA without photoactivation were designed. They contain a combination of a mismatch-directing metalloinsertor, [Rh(bpy)2(chrysi)]3+ (bpy=2,2'-bipyridyl, chrysi=5,6-chrysenequinone diimine), and an oxidative cleavage functionality, [Cu(phen)2]+ (Cu). Both unconjugated (Rh+Cu) and conjugated (Rh-Cu) frameworks of the Rh insertor and Cu were prepared. Compared to Cu, both constructs Rh+Cu and Rh-Cu exhibit efficient site-specific DNA scission only with mismatched DNA, confirmed by experiments with 32P-labeled oligonucleotides. Furthermore, these studies indicate that DNA cleavage occurs near the mismatch in the minor groove and on both strands. Interestingly, the order of reactivity of the three systems with a CC mismatch is Rh+Cu>Rh-Cu>>Cu. Rh binding appears to direct Cu reactivity with or without tethering. These results illustrate advantages and disadvantages in bifunctional conjugation.
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Affiliation(s)
- Mi Hee Lim
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, USA
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Cordier C, Pierre VC, Barton JK. Insertion of a bulky rhodium complex into a DNA cytosine-cytosine mismatch: an NMR solution study. J Am Chem Soc 2007; 129:12287-95. [PMID: 17877349 PMCID: PMC2748819 DOI: 10.1021/ja0739436] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The bulky octahedral complex Rh(bpy)2chrysi3+ (chrysi = 5,6-chrysenequinonediimine) binds single-base mismatches in a DNA duplex with micromolar binding affinities and high selectivity. Here we present an NMR solution study to characterize the binding mode of this bulky metal complex with its target CC mismatch in the oligonucleotide duplex (5'-CGGACTCCG-3')2. Both NOESY and COSY studies indicate that Rh(bpy)2chrysi3+ inserts deeply in the DNA at the mismatch site via the minor groove and with ejection of both destabilized cytosines into the opposite major groove. The insertion only minimally distorts the conformation of the oligonucleotide local to the binding site. Both flanking, well-matched base pairs remain tightly hydrogen-bonded to each other, and 2D DQF-COSY experiments indicate that all sugars maintain their original C2'-endo conformation. Remarkably, 31P NMR reveals that opening of the phosphate angles from a BI to a BII conformation is sufficient for insertion of the bulky metal complex. These results corroborate those obtained crystallographically and, importantly, provide structural evidence for this specific insertion mode in solution.
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