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A first-in-class clinical G-quadruplex-targeting drug. The bench-to-bedside translation of the fluoroquinolone QQ58 to CX-5461 (Pidnarulex). Bioorg Med Chem Lett 2022; 77:129016. [DOI: 10.1016/j.bmcl.2022.129016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 09/29/2022] [Accepted: 09/29/2022] [Indexed: 11/20/2022]
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Kawano S, Fujimoto K, Yasuda K, Ikeda S. DNA binding activity of the proximal C-terminal domain of rat DNA topoisomerase IIβ is involved in ICRF-193-induced closed-clamp formation. PLoS One 2020; 15:e0239466. [PMID: 32960919 PMCID: PMC7508362 DOI: 10.1371/journal.pone.0239466] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 09/08/2020] [Indexed: 11/30/2022] Open
Abstract
DNA topoisomerase II (topo II) is an essential enzyme that regulates DNA topology by DNA cleavage and re-ligation. In vertebrates, there are two isozymes, α and β. The C-terminal domain (CTD) of the isozymes, which shows a low degree of sequence homology between α and β, is involved in each isozyme-specific intracellular behavior. The CTD of topo IIβ is supposedly involved in topo II regulation. Topo IIβ is maintained in an inactive state in the nucleoli by the binding of RNA to the 50-residue region termed C-terminal regulatory domain (CRD) present in the CTD. Although in vitro biochemical analysis indicates that the CTD of topo IIβ has DNA binding activity, it is unclear whether CTD influences catalytic reaction in the nucleoplasm. Here, we show that the proximal CTD (hereafter referred to as pCTD) of rat topo IIβ, including the CRD, is involved in the catalytic reaction in the nucleoplasm. We identified the pCTD as a domain with DNA binding activity by in vitro catenation assay and electrophoretic mobility shift assay. Fluorescence recovery after photo-bleaching (FRAP) analysis of pCTD-lacking mutant (ΔpCTD) showed higher mobility in nucleoplasm than that of the wild-type enzyme, indicating that the pCTD also affected the nuclear dynamics of topo IIβ. ICRF-193, one of the topo II catalytic inhibitors, induces the formation of closed-clamp intermediates of topo II. Treatment of ΔpCTD with ICRF-193 significantly decreased the efficiency of closed-clamp formation. Altogether, our data indicate that the binding of topo IIβ to DNA through the pCTD is required for the catalytic reaction in the nucleoplasm.
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Affiliation(s)
- Shinji Kawano
- Department of Biochemistry, Faculty of Science, Okayama University of Science, Okayama, Japan
- * E-mail:
| | - Kunpei Fujimoto
- Department of Biochemistry, Faculty of Science, Okayama University of Science, Okayama, Japan
| | - Kazushi Yasuda
- Department of Biochemistry, Faculty of Science, Okayama University of Science, Okayama, Japan
| | - Shogo Ikeda
- Department of Biochemistry, Faculty of Science, Okayama University of Science, Okayama, Japan
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Morotomi-Yano K, Saito S, Adachi N, Yano KI. Dynamic behavior of DNA topoisomerase IIβ in response to DNA double-strand breaks. Sci Rep 2018; 8:10344. [PMID: 29985428 PMCID: PMC6037730 DOI: 10.1038/s41598-018-28690-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 06/27/2018] [Indexed: 12/11/2022] Open
Abstract
DNA topoisomerase II (Topo II) is crucial for resolving topological problems of DNA and plays important roles in various cellular processes, such as replication, transcription, and chromosome segregation. Although DNA topology problems may also occur during DNA repair, the possible involvement of Topo II in this process remains to be fully investigated. Here, we show the dynamic behavior of human Topo IIβ in response to DNA double-strand breaks (DSBs), which is the most harmful form of DNA damage. Live cell imaging coupled with site-directed DSB induction by laser microirradiation demonstrated rapid recruitment of EGFP-tagged Topo IIβ to the DSB site. Detergent extraction followed by immunofluorescence showed the tight association of endogenous Topo IIβ with DSB sites. Photobleaching analysis revealed that Topo IIβ is highly mobile in the nucleus. The Topo II catalytic inhibitors ICRF-187 and ICRF-193 reduced the Topo IIβ mobility and thereby prevented Topo IIβ recruitment to DSBs. Furthermore, Topo IIβ knockout cells exhibited increased sensitivity to bleomycin and decreased DSB repair mediated by homologous recombination (HR), implicating the role of Topo IIβ in HR-mediated DSB repair. Taken together, these results highlight a novel aspect of Topo IIβ functions in the cellular response to DSBs.
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Affiliation(s)
- Keiko Morotomi-Yano
- Department of Bioelectrics, Institute of Pulsed Power Science, Kumamoto University, Kumamoto, 860-8555, Japan
| | - Shinta Saito
- Department of Life and Environmental System Science, Graduate School of Nanobioscience, Yokohama City University, Yokohama, 236-0027, Japan
| | - Noritaka Adachi
- Department of Life and Environmental System Science, Graduate School of Nanobioscience, Yokohama City University, Yokohama, 236-0027, Japan.,Advanced Medical Research Center, Yokohama City University, Yokohama, 236-0004, Japan
| | - Ken-Ichi Yano
- Department of Bioelectrics, Institute of Pulsed Power Science, Kumamoto University, Kumamoto, 860-8555, Japan.
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Pedersen RT, Kruse T, Nilsson J, Oestergaard VH, Lisby M. TopBP1 is required at mitosis to reduce transmission of DNA damage to G1 daughter cells. J Cell Biol 2015; 210:565-82. [PMID: 26283799 PMCID: PMC4539992 DOI: 10.1083/jcb.201502107] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Genome integrity is critically dependent on timely DNA replication and accurate chromosome segregation. Replication stress delays replication into G2/M, which in turn impairs proper chromosome segregation and inflicts DNA damage on the daughter cells. Here we show that TopBP1 forms foci upon mitotic entry. In early mitosis, TopBP1 marks sites of and promotes unscheduled DNA synthesis. Moreover, TopBP1 is required for focus formation of the structure-selective nuclease and scaffold protein SLX4 in mitosis. Persistent TopBP1 foci transition into 53BP1 nuclear bodies (NBs) in G1 and precise temporal depletion of TopBP1 just before mitotic entry induced formation of 53BP1 NBs in the next cell cycle, showing that TopBP1 acts to reduce transmission of DNA damage to G1 daughter cells. Based on these results, we propose that TopBP1 maintains genome integrity in mitosis by controlling chromatin recruitment of SLX4 and by facilitating unscheduled DNA synthesis.
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Affiliation(s)
| | - Thomas Kruse
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Jakob Nilsson
- The Novo Nordisk Foundation Center for Protein Research, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Vibe H Oestergaard
- Department of Biology, University of Copenhagen, DK-2200 Copenhagen N, Denmark
| | - Michael Lisby
- Department of Biology, University of Copenhagen, DK-2200 Copenhagen N, Denmark
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Onoda A, Hosoya O, Sano K, Kiyama K, Kimura H, Kawano S, Furuta R, Miyaji M, Tsutsui K, Tsutsui KM. Nuclear dynamics of topoisomerase IIβ reflects its catalytic activity that is regulated by binding of RNA to the C-terminal domain. Nucleic Acids Res 2014; 42:9005-20. [PMID: 25034690 PMCID: PMC4132749 DOI: 10.1093/nar/gku640] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
DNA topoisomerase II (topo II) changes DNA topology by cleavage/re-ligation cycle(s) and thus contributes to various nuclear DNA transactions. It is largely unknown how the enzyme is controlled in a nuclear context. Several studies have suggested that its C-terminal domain (CTD), which is dispensable for basal relaxation activity, has some regulatory influence. In this work, we examined the impact of nuclear localization on regulation of activity in nuclei. Specifically, human cells were transfected with wild-type and mutant topo IIβ tagged with EGFP. Activity attenuation experiments and nuclear localization data reveal that the endogenous activity of topo IIβ is correlated with its subnuclear distribution. The enzyme shuttles between an active form in the nucleoplasm and a quiescent form in the nucleolus in a dynamic equilibrium. Mechanistically, the process involves a tethering event with RNA. Isolated RNA inhibits the catalytic activity of topo IIβ in vitro through the interaction with a specific 50-residue region of the CTD (termed the CRD). Taken together, these results suggest that both the subnuclear distribution and activity regulation of topo IIβ are mediated by the interplay between cellular RNA and the CRD.
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Affiliation(s)
- Akihisa Onoda
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Osamu Hosoya
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Kuniaki Sano
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Kazuko Kiyama
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Hiroshi Kimura
- Laboratory of Biological Science, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka 565-0871, Japan
| | - Shinji Kawano
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Ryohei Furuta
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Mary Miyaji
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Ken Tsutsui
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
| | - Kimiko M Tsutsui
- Department of Neurogenomics, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, 2-5-1 Shikata-cho, Kita-ku, Okayama 700-8558, Japan
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Auzanneau C, Montaudon D, Jacquet R, Puyo S, Pouységu L, Deffieux D, Elkaoukabi-Chaibi A, De Giorgi F, Ichas F, Quideau S, Pourquier P. The polyphenolic ellagitannin vescalagin acts as a preferential catalytic inhibitor of the α isoform of human DNA topoisomerase II. Mol Pharmacol 2012; 82:134-41. [PMID: 22528119 DOI: 10.1124/mol.111.077537] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Polyphenolic ellagitannins are natural compounds that are often associated with the therapeutic activity of plant extracts used in traditional medicine. They display cancer-preventing activity in animal models by a mechanism that remains unclear. Potential targets have been proposed, including DNA topoisomerases II (Top2). Top2α and Top2β, the two isoforms of the human Top2, play a crucial role in the regulation of replication, transcription, and chromosome segregation. They are the target of anticancer agents used in the clinic such as anthracyclines (e.g., doxorubicin) or the epipodophyllotoxin etoposide. It was recently shown that the antitumor activity of etoposide was due primarily to the inhibition of Top2α, whereas inhibition of Top2β was responsible for the development of secondary malignancies, pointing to the need for more selective Top2α inhibitors. Here, we show that the polyphenolic ellagitannin vescalagin preferentially inhibits the decatenation activity of Top2α in vitro, by a redox-independent mechanism. In CEM cells, we also show that transient small interfering RNA-mediated down-regulation of Top2α but not of Top2β conferred a resistance to vescalagin, indicating that the α isoform is a preferential target. We further confirmed that Top2α inhibition was due to a catalytic inhibition of the enzyme because it did not induce DNA double-strand breaks in CEM-treated cells but prevented the formation of Top2α- rather than Top2β-DNA covalent complexes induced by etoposide. To our knowledge, vescalagin is the first example of a catalytic inhibitor for which cytotoxicity is due, at least in part, to the preferential inhibition of Top2α.
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Affiliation(s)
- Céline Auzanneau
- Institut National de la Santé et de la Recherche Médicale U916 and Université de Bordeaux, Institut Bergonié, Bordeaux, France
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Antineoplastic activity of the thiazolo[5,4-b]quinoline derivative D3CLP in K-562 cells is mediated through effector caspases activation. Eur J Med Chem 2011; 46:2102-8. [DOI: 10.1016/j.ejmech.2011.02.063] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2010] [Revised: 02/17/2011] [Accepted: 02/24/2011] [Indexed: 12/17/2022]
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Kawamura R, Pope LH, Christensen MO, Sun M, Terekhova K, Boege F, Mielke C, Andersen AH, Marko JF. Mitotic chromosomes are constrained by topoisomerase II-sensitive DNA entanglements. ACTA ACUST UNITED AC 2010; 188:653-63. [PMID: 20194637 PMCID: PMC2835934 DOI: 10.1083/jcb.200910085] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Chromatin entanglements undergo specific protein-mediated compaction to fold into mitotic chromosomes. We have analyzed the topological organization of chromatin inside mitotic chromosomes. We show that mitotic chromatin is heavily self-entangled through experiments in which topoisomerase (topo) II is observed to reduce mitotic chromosome elastic stiffness. Single chromosomes were relaxed by 35% by exogenously added topo II in a manner that depends on hydrolysable adenosine triphosphate (ATP), whereas an inactive topo II cleavage mutant did not change chromosome stiffness. Moreover, experiments using type I topos produced much smaller relaxation effects than topo II, indicating that chromosome relaxation by topo II is caused by decatenation and/or unknotting of double-stranded DNA. In further experiments in which chromosomes are first exposed to protease to partially release protein constraints on chromatin, ATP alone relaxes mitotic chromosomes. The topo II–specific inhibitor ICRF-187 blocks this effect, indicating that it is caused by endogenous topo II bound to the chromosome. Our experiments show that DNA entanglements act in concert with protein-mediated compaction to fold chromatin into mitotic chromosomes.
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Affiliation(s)
- Ryo Kawamura
- Department of Physics, University of Illinois at Chicago, Chicago, IL 60607, USA
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9
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Germe T, Miller K, Cooper JP. A non-canonical function of topoisomerase II in disentangling dysfunctional telomeres. EMBO J 2009; 28:2803-11. [PMID: 19680223 PMCID: PMC2750024 DOI: 10.1038/emboj.2009.223] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2009] [Accepted: 07/13/2009] [Indexed: 11/09/2022] Open
Abstract
The decatenation activity of topoisomerase II (Top2), which is widely conserved within the eukaryotic domain, is essential for chromosomal segregation in mitosis. It is less clear, however, whether Top2 performs the same function uniformly across the whole genome, and whether all its functions rely on decatenation. In the fission yeast, Schizosaccharomyces pombe, telomeres are bound by Taz1, which promotes smooth replication fork progression through the repetitive telomeric sequences. Hence, replication forks stall at taz1 Delta telomeres. This leads to telomeric entanglements at low temperatures (
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Affiliation(s)
- Thomas Germe
- Telomere Biology Laboratory, Cancer Research, London, UK
| | - Kyle Miller
- Telomere Biology Laboratory, Cancer Research, London, UK
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Johnson M, Phua HH, Bennett SC, Spence JM, Farr CJ. Studying vertebrate topoisomerase 2 function using a conditional knockdown system in DT40 cells. Nucleic Acids Res 2009; 37:e98. [PMID: 19494182 PMCID: PMC2724289 DOI: 10.1093/nar/gkp480] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
DT40 is a B-cell lymphoma-derived avian cell line widely used to study cell autonomous gene function because of the high rates with which DNA constructs are homologously recombined into its genome. Here, we demonstrate that the power of the DT40 system can be extended yet further through the use of RNA interference as an alternative to gene targeting. We have generated and characterized stable DT40 transfectants in which both topo 2 genes have been in situ tagged using gene targeting, and from which the mRNA of both topoisomerase 2 isoforms can be conditionally depleted through the tetracycline-induced expression of short hairpin RNAs. The cell cycle phenotype of topo 2-depleted DT40 cells has been compared with that previously reported for other vertebrate cells depleted either of topo 2α through gene targeting, or depleted of both isoforms simultaneously by transient RNAi. In addition, the DT40 knockdown system has been used to explore whether excess catenation arising through topo 2 depletion is sufficient to trigger the G2 catenation (or decatenation) checkpoint, proposed to exist in differentiated vertebrate cells.
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Affiliation(s)
- Mark Johnson
- Department of Genetics, University of Cambridge, Downing St, Cambridge CB2 3EH, UK
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Abstract
Eukaryotic type II topoisomerases (Topo II) are implicated in a wide range of cellular processes. Cells in which Topo II protein has been specifically depleted or mutated provide powerful systems for analysing the normal in vivo functions of Topo II proteins and for assessing their roles in various chemotherapy regimens. Summarised here are the ways in which Topo II has been depleted or mutated in animal cells and the type of information gleaned. The cell lines generated are tabulated and represent a useful resource for further in vivo studies of Topo II function, one that we expect to grow in size and utility in the coming years.
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Affiliation(s)
- Andrew C G Porter
- Department of Haematology, Imperial College Faculty of Medicine, London, UK
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Yang SY, Jia XZ, Feng LY, Li SY, An GS, Ni JH, Jia HT. Inhibition of topoisomerase II by 8-chloro-adenosine triphosphate induces DNA double-stranded breaks in 8-chloro-adenosine-exposed human myelocytic leukemia K562 cells. Biochem Pharmacol 2008; 77:433-43. [PMID: 19014910 DOI: 10.1016/j.bcp.2008.10.022] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2008] [Revised: 10/21/2008] [Accepted: 10/21/2008] [Indexed: 11/15/2022]
Abstract
8-Chloro-cAMP and 8-chloro-adenosine (8-Cl-Ado) are known to inhibit proliferation of cancer cells by converting 8-Cl-Ado into an ATP analog, 8-chloro-ATP (8-Cl-ATP). Because type II topoisomerases (Topo II) are ATP-dependent, we infer that 8-Cl-Ado exposure might interfere with Topo II activities and DNA metabolism in cells. We found that 8-Cl-Ado exposure inhibited Topo II-catalytic activities in K562 cells, as revealed by decreased relaxation of the supercoiled pUC19 DNA and inhibited decatenation of the kinetoplast DNA (kDNA). In vitro assays showed that 8-Cl-ATP, but not 8-Cl-Ado, could directly inhibit Topo IIalpha-catalyzed relaxation and decatenation of substrate DNA. Furthermore, 8-Cl-ATP inhibited Topo II-catalyzed ATP hydrolysis and increased salt-stabilized closed clamp. In addition, 8-Cl-Ado exposure decreased bromo-deoxyuridine (BrdU) incorporation into DNA and led to enhanced DNA double-stranded breaks (DSBs) and to increased formation of gamma-H2AX nuclear foci in exposed K562 cells. Together, 8-Cl-Ado/8-Cl-ATP can inhibit Topo II activities in cells, thereby inhibiting DNA synthesis and inducing DNA DSBs, which may contribute to 8-Cl-Ado-inhibited proliferation of cancers.
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Affiliation(s)
- Sheng-Yong Yang
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Xue Yuan Road 38, Beijing 100083, PR China
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Boaz SM, Dominguez K, Shaman JA, Ward WS. Mouse spermatozoa contain a nuclease that is activated by pretreatment with EGTA and subsequent calcium incubation. J Cell Biochem 2008; 103:1636-45. [PMID: 17879959 PMCID: PMC2679532 DOI: 10.1002/jcb.21549] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
We demonstrated that mouse spermatozoa cleave their DNA into approximately 50 kb loop-sized fragments with topoisomerase IIB when treated with MnCl(2) and CaCl(2) in a process we term sperm chromatin fragmentation (SCF). SCF can be reversed by EDTA. A nuclease then further degrades the DNA in a process we term sperm DNA degradation (SDD). MnCl(2) alone could elicit this activity, but CaCl(2) had no effect. Here, we demonstrate the existence of a nuclease in the vas deferens that can be activated by ethylene glycol tetraacetic acid (EGTA) to digest the sperm DNA by SDD. Spermatozoa were extracted with salt and dithiothreitol to remove protamines and then incubated with EGTA. Next, the EGTA was removed and divalent cations were added. We found that Mn(2+), Ca(2+), or Zn(2+) could each activate SDD in spermatozoa but Mg(2+) could not. When the reaction was slowed by incubation on ice, EGTA pretreatment followed by incubation in Ca(2+) elicited the reversible fragmentation of sperm DNA evident in SCF. When the reactions were then incubated at 37 degrees C they progressed to the more complete degradation of DNA by SDD. EDTA could also be used to activate the nuclease, but required a higher concentration than EGTA. This EGTA-activatable nuclease activity was found in each fraction of the vas deferens plasma: in the spermatozoa, in the surrounding fluid, and in the insoluble components in the fluid. These results suggest that this sperm nuclease is regulated by a mechanism that is sensitive to EGTA, possibly by removing inhibition of a calcium binding protein.
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Affiliation(s)
| | | | | | - W. Steven Ward
- Address correspondence to: W. Steven Ward, Ph.D., Institute for Biogenesis Research, John A. Burns School of Medicine, University of Hawaii, 1960 East-West Road, Honolulu, HI 96822, Tel. 808 956-5189, Fax. 808 956-7316, E-Mail:
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Grauslund M, Thougaard AV, Füchtbauer A, Hofland KF, Hjorth PH, Jensen PB, Sehested M, Füchtbauer EM, Jensen LH. A mouse model for studying the interaction of bisdioxopiperazines with topoisomerase IIalpha in vivo. Mol Pharmacol 2007; 72:1003-14. [PMID: 17622580 DOI: 10.1124/mol.107.036970] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The bisdioxopiperazines such as (+)-(S)-4,4'-propylenedi-2,6-piperazinedione (dexrazoxane; ICRF-187), 1,2-bis(3,5-dioxopiperazin-1-yl)ethane (ICRF-154), and 4,4'-(1,2-dimethyl-1,2-ethanediyl)bis-2,6-piperazinedione (ICRF-193) are agents that inhibit eukaryotic topoisomerase II, whereas their ring-opened hydrolysis products are strong iron chelator. The clinically approved analog ICRF-187 is a pharmacological modulator of topoisomerase II poisons such as etoposide in preclinical animal models. ICRF-187 is also used to protect against anthracycline-induced cardiomyopathy and has recently been approved as an antidote for alleviating tissue damage and necrosis after accidental anthracycline extravasation. This dual modality of bisdioxopiperazines, including ICRF-187, raises the question of whether their pharmacological in vivo effects are mediated through interaction with topoisomerase II or via their intracellular iron chelating activity. In an attempt to distinguish between these possibilities, we here present a transgenic mouse model aimed at identifying the contribution of topoisomerase IIalpha to the effects of bisdioxopiperazines. A tyrosine 165 to serine mutation (Y165S) in topoisomerase IIalpha, demonstrated previously to render the human ortholog of this enzyme highly resistant toward bisdioxopiperazines, was introduced at the TOP2A locus in mouse embryonic stem cells by targeted homologous recombination. These cells were used for the generation of transgenic TOP2A(Y165S/+) mice, which were demonstrated to be resistant toward the general toxicity of both ICRF-187 and ICRF-193. Hematological measurements indicate that this is most likely caused by a decreased ability of these agents to induce myelosuppression in TOP2A(Y165S/+) mice, highlighting the role of topoisomerase IIalpha in this process. The biological and pharmacological implications of these findings are discussed, and areas for further investigations are proposed.
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Affiliation(s)
- Morten Grauslund
- Experimental Pathology Unit, Department of Pathology, Rigshospitalet afs. 3731, Biocenter, Bygning 2, 3 sal., Ole Maaløes vej 5, DK-2100 Copenhagen O, Denmark
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15
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Campbell KJ, O'Shea JM, Perkins ND. Differential regulation of NF-kappaB activation and function by topoisomerase II inhibitors. BMC Cancer 2006; 6:101. [PMID: 16630341 PMCID: PMC1459870 DOI: 10.1186/1471-2407-6-101] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2005] [Accepted: 04/21/2006] [Indexed: 11/19/2022] Open
Abstract
Background While many common chemotherapeutic drugs and other inducers of DNA-damage result in both NF-κB nuclear translocation and DNA-binding, we have previously observed that, depending on the precise stimulus, there is great diversity of the function of NF-κB. In particular, we found that treatment of U-2 OS osteosarcoma cells with the anthracycine daunorubicin or with ultraviolet (UV-C) light resulted in a form of NF-κB that repressed rather than induced NF-κB reporter plasmids and the expression of specific anti-apoptotic genes. Anthracyclines such as daunorubicin can induce DNA-damage though inhibiting topoisomerase II, intercalating with DNA and undergoing redox cycling to produce oxygen free radicals. In this study we have investigated other anthracyclines, doxorubicin and aclarubicin, as well as the anthracenedione mitoxantrone together with the topoisomerase II inhibitor ICRF-193, which all possess differing characteristics, to determine which of these features is specifically required to induce both NF-κB DNA-binding and transcriptional repression in U-2 OS cells. Results The use of mitoxantrone, which does not undergo redox cycling, and the reducing agent epigallocatechingallate (EGCG) demonstrated that oxygen free radical production is not required for induction of NF-κB DNA-binding and transcriptional repression by these agents and UV-C. In addition, the use of aclarubicin, which does not directly inhibit topoisomerase II and ICRF-193, which inhibits topoisomerase II but does not intercalate into DNA, demonstrated that topoisomerase II inhibition is not sufficient to induce the repressor form of NF-κB. Conclusion Induction of NF-κB DNA-binding and transcriptional repression by topoisomerase II inhibitors was found to correlate with an ability to intercalate into DNA. Although data from our and other laboratories indicates that topoisomerase II inhibition and oxygen free radicals do regulate NF-κB, they are not required for the particular ability of NF-κB to repress rather than activate transcription. Together with our previous data, these results demonstrate that the nature of the NF-κB response is context dependent. In a clinical setting such effects could profoundly influence the response to chemotherapy and suggest that new methods of analyzing NF-κB function could have both diagnostic and prognostic value.
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Affiliation(s)
- Kirsteen J Campbell
- School of Life Sciences, Division of Gene Regulation and Expression, MSI/WTB, Complex, Dow Street, University of Dundee, Dundee, DD1 5EH, Scotland, UK
| | - John M O'Shea
- School of Life Sciences, Division of Gene Regulation and Expression, MSI/WTB, Complex, Dow Street, University of Dundee, Dundee, DD1 5EH, Scotland, UK
| | - Neil D Perkins
- School of Life Sciences, Division of Gene Regulation and Expression, MSI/WTB, Complex, Dow Street, University of Dundee, Dundee, DD1 5EH, Scotland, UK
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Lemaitre JM, Danis E, Pasero P, Vassetzky Y, Méchali M. Mitotic Remodeling of the Replicon and Chromosome Structure. Cell 2005; 123:787-801. [PMID: 16325575 DOI: 10.1016/j.cell.2005.08.045] [Citation(s) in RCA: 158] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2005] [Revised: 07/20/2005] [Accepted: 08/29/2005] [Indexed: 01/28/2023]
Abstract
Animal cloning by nuclear-transfer experiments frequently fails due to the inability of transplanted nuclei to support normal embryonic development. We show here that the formation of mitotic chromosomes in the egg context is crucial for adapting differentiated nuclei for early development. Differentiated erythrocyte nuclei replicate inefficiently in Xenopus eggs but do so as rapidly as sperm nuclei if a prior single mitosis is permitted. This mitotic remodeling involves a topoisomerase II-dependent shortening of chromatin loop domains and an increased recruitment of replication initiation factors onto chromatin, leading to a short interorigin spacing characteristic of early developmental stages. It also occurs within each early embryonic cell cycle and dominantly regulates initiation of DNA replication for the subsequent S phase. These results indicate that mitotic conditioning is crucial to reset the chromatin structure of differentiated adult donor cells for embryonic DNA replication and suggest that it is an important step in nuclear cloning.
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Affiliation(s)
- Jean-Marc Lemaitre
- Genome Dynamics and Development, Institute of Human Genetics, CNRS, 141 rue de la Cardonille, 34396 Montpellier, France
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Jensen LH, Dejligbjerg M, Hansen LT, Grauslund M, Jensen PB, Sehested M. Characterisation of cytotoxicity and DNA damage induced by the topoisomerase II-directed bisdioxopiperazine anti-cancer agent ICRF-187 (dexrazoxane) in yeast and mammalian cells. BMC Pharmacol 2004; 4:31. [PMID: 15575955 PMCID: PMC545072 DOI: 10.1186/1471-2210-4-31] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2004] [Accepted: 12/02/2004] [Indexed: 12/17/2022] Open
Abstract
Background Bisdioxopiperazine anti-cancer agents are inhibitors of eukaryotic DNA topoisomerase II, sequestering this protein as a non-covalent protein clamp on DNA. It has been suggested that such complexes on DNA represents a novel form of DNA damage to cells. In this report, we characterise the cytotoxicity and DNA damage induced by the bisdioxopiperazine ICRF-187 by a combination of genetic and molecular approaches. In addition, the well-established topoisomerase II poison m-AMSA is used for comparison. Results By utilizing a panel of Saccharomyces cerevisiae single-gene deletion strains, homologous recombination was identified as the most important DNA repair pathway determining the sensitivity towards ICRF-187. However, sensitivity towards m-AMSA depended much more on this pathway. In contrast, disrupting the post replication repair pathway only affected sensitivity towards m-AMSA. Homologous recombination (HR) defective irs1SF chinese hamster ovary (CHO) cells showed increased sensitivity towards ICRF-187, while their sensitivity towards m-AMSA was increased even more. Furthermore, complementation of the XRCC3 deficiency in irs1SF cells fully abrogated hypersensitivity towards both drugs. DNA-PKcs deficient V3-3 CHO cells having reduced levels of non-homologous end joining (NHEJ) showed slightly increased sensitivity to both drugs. While exposure of human small cell lung cancer (SCLC) OC-NYH cells to m-AMSA strongly induced γH2AX, exposure to ICRF-187 resulted in much less induction, showing that ICRF-187 generates fewer DNA double strand breaks than m-AMSA. Accordingly, when yeast cells were exposed to equitoxic concentrations of ICRF-187 and m-AMSA, the expression of DNA damage-inducible genes showed higher levels of induction after exposure to m-AMSA as compared to ICRF-187. Most importantly, ICRF-187 stimulated homologous recombination in SPD8 hamster lung fibroblast cells to lower levels than m-AMSA at all cytotoxicity levels tested, showing that the mechanism of action of bisdioxopiperazines differs from that of classical topoisomerase II poisons in mammalian cells. Conclusion Our results point to important differences in the mechanism of cytotoxicity induced by bisdioxopiperazines and topoisomerase II poisons, and suggest that bisdioxopiperazines kill cells by a combination of DNA break-related and DNA break-unrelated mechanisms.
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Affiliation(s)
- Lars H Jensen
- Department of Pathology, Diagnostic Centre, Rigshospitalet 5444, Frederik V's Vej 11, DK-2100 Copenhagen, Denmark
- Laboratory of Experimental Medical Oncology, Finsen Centre, Rigshospitalet 5074, Blegdamsvej 9, DK-2100 Copenhagen, Denmark
| | - Marielle Dejligbjerg
- Department of Pathology, Diagnostic Centre, Rigshospitalet 5444, Frederik V's Vej 11, DK-2100 Copenhagen, Denmark
| | - Lasse T Hansen
- Institute of Molecular Pathology, University of Copenhagen, Frederik V's Vej 11, DK-2100, Copenhagen, Denmark
| | - Morten Grauslund
- Department of Pathology, Diagnostic Centre, Rigshospitalet 5444, Frederik V's Vej 11, DK-2100 Copenhagen, Denmark
| | - Peter B Jensen
- Laboratory of Experimental Medical Oncology, Finsen Centre, Rigshospitalet 5074, Blegdamsvej 9, DK-2100 Copenhagen, Denmark
| | - Maxwell Sehested
- Department of Pathology, Diagnostic Centre, Rigshospitalet 5444, Frederik V's Vej 11, DK-2100 Copenhagen, Denmark
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Oestergaard VH, Giangiacomo L, Bjergbaek L, Knudsen BR, Andersen AH. Hindering the strand passage reaction of human topoisomerase IIalpha without disturbing DNA cleavage, ATP hydrolysis, or the operation of the N-terminal clamp. J Biol Chem 2004; 279:28093-9. [PMID: 15123700 DOI: 10.1074/jbc.m402120200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
DNA topoisomerase II is an essential enzyme that releases a topological strain in DNA by introduction of transient breaks in one DNA helix through which another helix is passed. While changing DNA topology, ATP is required to drive the enzyme through a series of conformational changes dependent on interdomain communication. We have characterized a human topoisomerase IIalpha enzyme with a two-amino acid insertion at position 351 in the transducer domain. The mutation specifically abolishes the DNA strand passage event of the enzyme, probably because of a sterical hindrance of T-segment transport. Thus, the enzyme fails to decatenate and relax DNA, even though it is fully capable of ATP hydrolysis, closure of the N-terminal clamp, and DNA cleavage. The cleavage activity is increased, suggesting that the transducer domain has a role in regulating DNA cleavage. Furthermore, the enzyme has retained a tendency to increase DNA cleavage upon nucleotide binding and also responds to DNA with elevated ATP hydrolysis. However, the DNA-mediated increase in ATP hydrolysis is lower than that obtained with the wild-type enzyme but similar to that of a cleavage-deficient topoisomerase IIalpha enzyme. Our results strongly suggest that the strand passage event is required for efficient DNA stimulation of topoisomerase II-mediated ATP hydrolysis, whereas the stimulation occurs independent of the DNA cleavage reaction per se. A comparison of the strand passage deficient-enzyme described here and the cleavage-deficient enzyme may have applications in other studies where a clear distinction between strand passage and topoisomerase II-mediated DNA cleavage is desirable.
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Affiliation(s)
- Vibe H Oestergaard
- Department of Molecular Biology, University of Aarhus, C. F. Møllers Allé, Building 130, 8000 Aarhus C, Denmark
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