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Gonzalez-Buendia E, Zhao J, Wang L, Mukherjee S, Zhang D, Arrieta VA, Feldstein E, Kane JR, Kang SJ, Lee-Chang C, Mahajan A, Chen L, Realubit R, Karan C, Magnuson L, Horbinski C, Marshall SA, Sarkaria JN, Mohyeldin A, Nakano I, Bansal M, James CD, Brat DJ, Ahmed A, Canoll P, Rabadan R, Shilatifard A, Sonabend AM. TOP2B Enzymatic Activity on Promoters and Introns Modulates Multiple Oncogenes in Human Gliomas. Clin Cancer Res 2021; 27:5669-5680. [PMID: 34433651 PMCID: PMC8818263 DOI: 10.1158/1078-0432.ccr-21-0312] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 05/07/2021] [Accepted: 07/28/2021] [Indexed: 01/07/2023]
Abstract
PURPOSE The epigenetic mechanisms involved in transcriptional regulation leading to malignant phenotype in gliomas remains poorly understood. Topoisomerase IIB (TOP2B), an enzyme that decoils and releases torsional forces in DNA, is overexpressed in a subset of gliomas. Therefore, we investigated its role in epigenetic regulation in these tumors. EXPERIMENTAL DESIGN To investigate the role of TOP2B in epigenetic regulation in gliomas, we performed paired chromatin immunoprecipitation sequencing for TOP2B and RNA-sequencing analysis of glioma cell lines with and without TOP2B inhibition and in human glioma specimens. These experiments were complemented with assay for transposase-accessible chromatin using sequencing, gene silencing, and mouse xenograft experiments to investigate the function of TOP2B and its role in glioma phenotypes. RESULTS We discovered that TOP2B modulates transcription of multiple oncogenes in human gliomas. TOP2B regulated transcription only at sites where it was enzymatically active, but not at all native binding sites. In particular, TOP2B activity localized in enhancers, promoters, and introns of PDGFRA and MYC, facilitating their expression. TOP2B levels and genomic localization was associated with PDGFRA and MYC expression across glioma specimens, which was not seen in nontumoral human brain tissue. In vivo, TOP2B knockdown of human glioma intracranial implants prolonged survival and downregulated PDGFRA. CONCLUSIONS Our results indicate that TOP2B activity exerts a pleiotropic role in transcriptional regulation of oncogenes in a subset of gliomas promoting a proliferative phenotype.
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Affiliation(s)
- Edgar Gonzalez-Buendia
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Junfei Zhao
- Department of Systems Biology, Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York
| | - Lu Wang
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Subhas Mukherjee
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Daniel Zhang
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Víctor A Arrieta
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
- PECEM, Facultad de Medicina, Universidad Nacional Autónoma de México, México
| | - Eric Feldstein
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - J Robert Kane
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Seong Jae Kang
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Catalina Lee-Chang
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Aayushi Mahajan
- Department of Pathology and Cell Biology, Columbia University, New York, New York
| | - Li Chen
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Ronald Realubit
- High-Throughput Screening Genome Center, Columbia University, New York, New York
| | - Charles Karan
- High-Throughput Screening Genome Center, Columbia University, New York, New York
| | - Lisa Magnuson
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Craig Horbinski
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Stacy A Marshall
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Jann N Sarkaria
- Department of Radiation Oncology, Mayo Clinic, Rochester, Minnesota
| | - Ahmed Mohyeldin
- Department of Neurosurgery, Ohio State University, Columbus, Ohio
| | - Ichiro Nakano
- Department of Neurosurgery, University of Alabama, Birmingham, Alabama
| | - Mukesh Bansal
- Department of Systems Biology, Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York
| | - Charles D James
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Daniel J Brat
- Department of Pathology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Atique Ahmed
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Peter Canoll
- Department of Pathology and Cell Biology, Columbia University, New York, New York
| | - Raul Rabadan
- Department of Systems Biology, Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York
| | - Ali Shilatifard
- Department of Biochemistry and Molecular Genetics, Feinberg School of Medicine, Northwestern University, Chicago, Illinois
| | - Adam M Sonabend
- Department of Neurosurgery, Feinberg School of Medicine, Northwestern University and Northwestern Medicine Malnati Brain Tumor Institute of the Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, Illinois.
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Gieseler F, Boege F, Biersack H, Spohn B, Clark M, Wilms K. Nuclear Topoisomerase II Activity Changes During HL-60 Leukemic Cell Differentiation: Alterations in Drug Sensitivity and pH Dependency. Leuk Lymphoma 2009; 5:273-9. [DOI: 10.3109/10428199109068137] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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3
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Effect of active compounds isolated from Pteris semipinnata L on DNA topoisomerases and tyrosine protein kinase and expression of C-MYC in lung adenocarcinoma cells. Chin J Cancer Res 2001. [DOI: 10.1007/s11670-001-0025-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Sato N, Mizumoto K, Kusumoto M, Niiyama H, Maehara N, Ogawa T, Tanaka M. 9-Hydroxyellipticine inhibits telomerase activity in human pancreatic cancer cells. FEBS Lett 1998; 441:318-21. [PMID: 9883907 DOI: 10.1016/s0014-5793(98)01571-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
There is increasing interest in identifying potent inhibitors of telomerase because the enzyme plays a crucial role in the development of cellular immortality and carcinogenesis. We hypothesized that 9-hydroxyellipticine (9-HE), an antitumor alkaloid, would inhibit telomerase activity because the drug has a unique mechanism of inhibiting phosphorylation of mutant p53 protein via inhibition of protein kinases, thereby restoring wild-type p53 function. This study was conducted to examine the effect of 9-HE on telomerase activity in human pancreatic cancer cells with differing p53 gene status. 9-HE treatment at relatively high concentrations resulted in rapid, complete inhibition of telomerase activity, irrespective of the p53 status. We conclude that 9-HE may exert a strong inhibitory effect on telomerase activity possibly through inhibition of protein kinases rather than through restoration of functional wild-type p53.
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Affiliation(s)
- N Sato
- Department of Surgery I, Kyushu University Faculty of Medicine, Fukuoka, Japan
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5
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Chang S, Hu T, Hsieh TS. Analysis of a core domain in Drosophila DNA topoisomerase II. Targeting of an antitumor agent ICRF-159. J Biol Chem 1998; 273:19822-8. [PMID: 9677416 DOI: 10.1074/jbc.273.31.19822] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
To investigate the biochemical properties of individual domains of eukaryotic topoisomerase (topo) II, two truncation mutants of Drosophila topo II were generated, ND406 and core domain. Both mutants lack the ATPase domain, corresponding to the N-terminal 406 amino acid residues in Drosophila protein. The core domain also lacks 240 amino acid residues of the hydrophilic C-terminal region. The mutant proteins have lost DNA strand passage activity while retaining the ability to cleave the DNA and the sequence preference in protein/DNA interaction. The cleavage experiments carried out in the presence of several topo II poisons suggest that the core domain is the key target for these drugs. We have used glass-fiber filter binding assay and CsCl density gradient ultracentrifugation to monitor the formation of a salt-stable, protein-clamp complex. Both truncation mutant proteins can form a clamp complex in the presence of an antitumor agent, ICRF-159, suggesting that the drug targets the core domain of the enzyme and promotes the intradimeric closure at the N-terminal interface of the core domain. Furthermore, the salt stability of the closed protein clamp induced by ICRF-159 depends on the presence and closure of the N-terminal ATPase domain.
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Affiliation(s)
- S Chang
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA
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6
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Borde V, Duguet M. DNA topoisomerase II sites in the histone H4 gene during the highly synchronous cell cycle of Physarum polycephalum. Nucleic Acids Res 1998; 26:2042-49. [PMID: 9547257 PMCID: PMC147523 DOI: 10.1093/nar/26.9.2042] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
The nearly perfect synchrony of nuclear division in a plasmodium of Physarum polycephalum provides a powerful system to analyze topoisomerase II cleavage sites in the course of the cell cycle. The histone H4 locus, whose schedule of replication and transcription is precisely known, was chosen for this analysis. Drug-induced topoisomerase II sites are clustered downstream of the histone H4 gene and appear highly dependent on cell cycle stage. They were only detected in mitosis and at the very beginning of S phase, precisely at the time of replication of the histone H4 region. The sites, which were absent in G2 phase, reappeared at the next mitosis. Remarkably, DNase I hypersensitive sites occurred in nearly the same location, but their schedule was totally different: they were absent in mitosis and present in G2. This schedule follows H4 transcription, which peaks in mid-S phase and in the second part of G2 phase and is off during mitosis. These results suggest that topoisomerase II may not be involved in transcription, but plays a role in remodeling chromatin structure, both during chromosome condensation in prophase/metaphase to allow their decatenation and during chromosome decondensation after metaphase to allow replication fork passage throughout the region.
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Affiliation(s)
- V Borde
- Laboratoire d'Enzymologie des Acides Nucléiques, Institut de Génétique et Microbiologie, URA 2225 CNRS, Bât. 400, Université de Paris Sud, Centre d'Orsay, 91405 Orsay Cedex, France
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7
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Hu T, Chang S, Hsieh T. Identifying Lys359 as a critical residue for the ATP-dependent reactions of Drosophila DNA topoisomerase II. J Biol Chem 1998; 273:9586-92. [PMID: 9545289 DOI: 10.1074/jbc.273.16.9586] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Substituting Lys359 with either Gln or Glu in the highly conserved QTK-loop in the DNA gyrase B protein homologous domain of Drosophila topoisomerase II inactivates its catalytic activities. Although strand passage and DNA-dependent ATPase activities are affected in these mutant proteins, their DNA cleavage activity is comparable with the wild-type enzyme and can be stimulated to the same level by topoisomerase-targeting anticancer drugs. The sequence specificity in the DNA cleavage reaction remains unaltered for the mutant proteins. We have used both glass fiber filter binding assay and CsCl density gradient ultracentrifugation to monitor the formation of a salt-stable, protein-clamp complex. Both Gln and Glu mutant proteins can form a clamp complex in the presence of 5'-adenylyl-beta,gamma-imidodiphosphate, albeit with a lower efficiency than the wild-type enzyme. However, the mutant proteins can form a stable complex either in the presence of ATP or in the absence of any cofactors. These results are in an interesting contrast with the wild-type enzyme, which cannot form a stable complex under similar conditions. Our data suggest that Lys359 is critical for the catalytic activity of topoisomerase II and may have an important function in the ATP signaling process.
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Affiliation(s)
- T Hu
- Department of Biochemistry, Duke University Medical Center, Durham, North Carolina 27710, USA
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8
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Borde V, Duguet M. The mapping of DNA topoisomerase sites in vivo: a tool to enlight the functions of topoisomerases. Biochimie 1998; 80:223-33. [PMID: 9615862 DOI: 10.1016/s0300-9084(98)80005-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The possibility to record a trace of the precise sites of topoisomerase action has been exploited for almost 12 years in many laboratories. The large majority of the studies were performed in vitro, giving a good picture of sequence specificities of topoisomerases, and of the preference of various drugs for some sequences. Only a relatively small number of reports concern in vivo studies. Their main conclusions are the following: i) topoisomerase II sites are often found near replication origins and termini, where they are supposed to play a role in the decatenation of daughter DNA molecules, and possibly in the initiation of replication; ii) topoisomerase II sites are found in the promoter region of many genes, but they seem related to the condensation state of chromatin in this region, rather than to transcription per se; iii) some topoisomerase II sites, resistant to high salt, are found in or near matrix associated regions (MARs), suggesting a role in loop anchorage or (and) in the control of topology of individual chromatin loops; iv) topoisomerase I sites appear less localized, acting all along the transcription units, where they seem directly involved in transcription; and v) topoisomerase I sites are possibly connected with replication fork progression and (or) with the termination of replication. Despite these advances, the precise role of topoisomerases in vivo is still poorly understood, especially in recombination and chromatin condensation and decondensation during the cell cycle. Future attempts should take into account the possible specialization of the multiple topoisomerases found in a given cell, and the use of highly synchronized systems.
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Affiliation(s)
- V Borde
- Laboratoire d'Enzymologie des Acides Nucléiques, URA 2225 CNRS, Université de Paris Sud, Centre d'Orsay, France
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9
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10
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Bunch RT, Povirk LF, Orr MS, Randolph JK, Fornari FA, Gewirtz DA. Influence of amsacrine (m-AMSA) on bulk and gene-specific DNA damage and c-myc expression in MCF-7 breast tumor cells. Biochem Pharmacol 1994; 47:317-29. [PMID: 8304976 DOI: 10.1016/0006-2952(94)90023-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
In the MCF-7 human breast tumor cell line, the aminoacridine, m-AMSA, induces protein-associated DNA strand breaks consistent with inhibition of topoisomerase II. However, neither single-strand nor double-strand breaks in DNA, determined using conventional assays, show a consistent relationship with m-AMSA-induced inhibition of growth. In contrast, when DNA strand breaks are determined by alkaline unwinding under the high salt conditions of the alkaline unwinding/Southern blotting (AU/SB) assay, developed by our laboratories, damage to DNA corresponds closely with growth inhibition. The AU/SB assay, which is capable of assessing breaks within large-scale domains (upwards of 1 megabase) surrounding genes of interest, was further utilized to explore the capacity of m-AMSA to induce damage within specific genomic regions that may regulate cell growth. Regions encompassing the transcriptionally active oncogenes, c-myc and c-fos, were found to be more susceptible to m-AMSA-induced strand breaks than the region encompassing the non-transcribed alpha-satellite DNA or the genome as a whole (bulk DNA). These findings demonstrate that m-AMSA may produce more pronounced damage within specific genomic regions than in bulk DNA, m-AMSA also preferentially altered expression of the c-myc oncogene; at an m-AMSA concentration where growth was inhibited by between 70 and 80%, steady-state c-myc mRNA levels declined to approximately 10-15% of control levels within 2-3 hr; furthermore, concentration-dependent reductions in c-myc expression appeared to coincide with growth inhibition. In addition, inhibition of [3H]thymidine incorporation after 2 hr directly paralleled inhibition of growth, suggesting an early effect at the level of DNA biosynthesis, possibly related to the down-regulation of c-myc expression. It is proposed that specific lesions, e.g., in regions surrounding the c-myc gene, as well as generalized lesions in DNA may lead to growth inhibition mediated by down-regulation of the expression of select growth regulatory genes, such as c-myc.
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Affiliation(s)
- R T Bunch
- Department of Pharmacology and Toxicology, Virginia Commonwealth, University/Medical College of Virginia, Richmond 23298
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11
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Osheroff N, Corbett AH, Robinson MJ. Mechanism of action of topoisomerase II-targeted antineoplastic drugs. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 1994; 29B:105-26. [PMID: 8996604 DOI: 10.1016/s1054-3589(08)61134-5] [Citation(s) in RCA: 56] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- N Osheroff
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37332-0146, USA
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12
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Riou JF, Gabillot M, Riou G. Analysis of topoisomerase II-mediated DNA cleavage of the c-myc gene during HL60 differentiation. FEBS Lett 1993; 334:369-72. [PMID: 8243649 DOI: 10.1016/0014-5793(93)80714-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
We have investigated the effect of mAMSA, a potent topoisomerase II inhibitor, on the c-myc proto-oncogene of the acute promyelocytic leukemia HL60 cell line during its differentiation. When HL60 cells were induced by dimethylsulfoxide (DMSO) to terminally differentiate, a rapid drop in the level of c-myc mRNA was observed, followed by an arrest of cell proliferation. In contrast, the level of topoisomerase II mRNA was transiently increased with a maximum at 6 h after DMSO addition and was then completely abolished after 48 h, indicating that topoisomerase II is activated during the onset of HL60 differentiation. In exponentially growing cells, treatment by mAMSA results in the formation of topoisomerase II-mediated double strand DNA breaks in the c-myc gene at positions where topoisomerase II would normally nick and reseal the two strands. In HL60 cells treated with both mAMSA and DMSO, the sites in the c-myc gene at which mAMSA had induced cleavage were not altered. However, a DNA cleavage site located at the end of the first c-myc exon (position +3100), was strongly stimulated by mAMSA and DMSO treatment. This site fell within a DNase I hypersensitive region encompassing the MYC intron factor 1 (MIF1) binding site, where transcription elongation is normally blocked during differentiation. These data indicate that a change of topoisomerase II binding to critical regulatory region of the c-myc gene is associated with the downregulation of this gene during differentiation.
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Affiliation(s)
- J F Riou
- Rhône-Poulenc Rorer SA. Département Biologie, Vitry-sur-Seine, France
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Baez A, Sepulveda J. Myeloid differentiation of HL-60 cells induced by anti-tumor drug 3-nitrobenzothiazolo[3,2-a]quinolinium. Leuk Res 1992; 16:363-70. [PMID: 1314318 DOI: 10.1016/0145-2126(92)90138-w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Drugs which elicit cell differentiation might have an important role in the treatment of leukemias and other neoplasias. Various chemotherapeutic agents promote leukemic cell differentiation. The HL-60 cell line is a useful model to study in vitro myeloid differentiation. Sublethal concentrations of 3-nitrobenzothiazolo[3,2-a]quinolinium (NBQ), an antitopoisomerase II drug, were given to HL-60 cells from one to five days to evaluate its capacity to induce differentiation. NBQ-induced HL-60 cells reduced nitroblue tetrazolium (NBT), increased MY-4 receptors, increased phagocytic activity and displayed the granulocytic morphology. Flow cytometric DNA analysis of NBQ-induced cells revealed an arrest in the G1 phase a reduction in the relative percentage of cells in S and G2+M phases. Our results suggest that NBQ induces an S-phase specific differentiation of HL-60 cells comparable to that previously described with dimethyl sulfoxide and retinoic acid. NBQ and its analogs, as differentiation inducers, may have potential utility as a novel therapeutic modality for leukemias.
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Affiliation(s)
- A Baez
- Department of Pharmacology, School of Medicine, University of Puerto Rico, Juan 00936-5067
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Ratain MJ, Rowley JD. Therapy-related acute myeloid leukemia secondary to inhibitors of topoisomerase II: from the bedside to the target genes. Ann Oncol 1992; 3:107-11. [PMID: 1318741 DOI: 10.1093/oxfordjournals.annonc.a058121] [Citation(s) in RCA: 102] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
In the past five years, several groups have reported acute myeloid leukemia (AML) often monoblastic, as a complication of chemotherapy regimens including the epipodophyllotoxins, etoposide and teniposide. This syndrome is distinct clinically, pathologically and cytogenetically from classical therapy-related myelodysplasia and AML. There is also evidence that other topoisomerase II inhibitors, such as the intercalating agents (including doxorubicin, mitoxantrone, and actinomycin D) may be leukemogenic. Furthermore, there may be further interactions from concomitant topoisomerase II inhibitors and alkylating agents. Topoisomerase II inhibitors induce DNA cleavage and other chromosomal aberrations, including sister chromatid exchanges. These clastogenic abnormalities are not fully understood, and may be specific for each cytotoxic agent. Work is in progress to clone breakpoints such as the t(9;11) and t(8;21) and the use of the resultant DNA probes will enhance our understanding of the leukemogenic process. Given the potential diversity in patients with secondary leukemia, cytogenetic studies should be mandatory for both enhancing our knowledge base and guiding treatment in individual patients. Clinicians must also be wary of the leukemogenic potential of 'dose-intense' regimens including agents such as etoposide and doxorubicin.
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MESH Headings
- Acute Disease
- Antineoplastic Agents/adverse effects
- DNA Damage/genetics
- Humans
- Leukemia, Monocytic, Acute/chemically induced
- Leukemia, Monocytic, Acute/enzymology
- Leukemia, Monocytic, Acute/genetics
- Leukemia, Myeloid/chemically induced
- Leukemia, Myeloid/enzymology
- Leukemia, Myeloid/genetics
- Neoplasms, Second Primary/enzymology
- Neoplasms, Second Primary/etiology
- Neoplasms, Second Primary/genetics
- Podophyllotoxin/adverse effects
- Topoisomerase II Inhibitors
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Affiliation(s)
- M J Ratain
- Department of Medicine, University of Chicago Pritzker School of Medicine, Illinois
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15
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Abstract
DNA is the most important target for drug and radiation induced cell killing. The mode of cell killing by cytotoxic drugs and radiation has been derived by correlating the type and quantity of DNA damage induced with lethality. Cytotoxic drugs can be classified by their main mode of action, while ionising radiation causes a range of lesions with the DNA double-strand break (dsb) being the most significant. Strand-breaks are measured from the reduction in the size of DNA molecules following treatment. Molecule size can be derived from the rate that DNA fragments sediment when centrifuged, elute through filters or migrate under electrophoresis. The effect of strand-breaks on DNA loop supercoiling allow a sensitive assay of DNA damage. Specific assays for base damage and drug adducts include changes in chromatographic mobility or binding by specific antibodies. By comparing the levels of damage in the genome overall with damage in specific gene targets, regions susceptible to damage induction, and varying in repair efficiency, have been revealed.
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Affiliation(s)
- S J Whitaker
- Radiotherapy Research Unit, Institute of Cancer Research, Sutton, Surrey, U.K
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Pommier Y, Capranico G, Orr A, Kohn KW. Distribution of topoisomerase II cleavage sites in simian virus 40 DNA and the effects of drugs. J Mol Biol 1991; 222:909-24. [PMID: 1662289 DOI: 10.1016/0022-2836(91)90585-t] [Citation(s) in RCA: 62] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The distributions of DNA cleavage sites induced by topoisomerase II in the presence or absence of specific drugs were mapped in the simian virus 40 genome. The drugs studied were 5-iminodaunorubicin, amsacrine (m-AMSA), teniposide (VM-26) and 2-methyl-9-hydroxyellipticinium; each produced a distinctive pattern of enhanced cleavage. Consistently intense cleavage, both in the presence and in the absence of drugs, occurred in the nuclear matrix-associated region. Since topoisomerase II is a major constituent of the nuclear matrix, and cleavage complexes include a covalent link between topoisomerase II and DNA, the findings suggest that topoisomerase II may function to attach DNA to the nuclear matrix. Cleavage usually occurred on both DNA strands with the expected four base-pair 5' stagger, and strong sites tended to occur within A/T runs such as have been associated with binding to the nuclear scaffold. Intense cleavage was present also in the replication termination region, but was absent from the vicinity of the replication origin. Cleavage intensities were found to change with time in a manner that depended both on the site and on the drug, suggesting that topoisomerase II can move along the DNA from a kinetically preferred site to a thermodynamically preferred site.
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Affiliation(s)
- Y Pommier
- Laboratory of Molecular Pharmacology, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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Lefevre D, Riou JF, Ahomadegbe JC, Zhou DY, Benard J, Riou G. Study of molecular markers of resistance to m-AMSA in a human breast cancer cell line. Decrease of topoisomerase II and increase of both topoisomerase I and acidic glutathione S transferase. Biochem Pharmacol 1991; 41:1967-79. [PMID: 1645555 DOI: 10.1016/0006-2952(91)90138-u] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Resistance to 0.8 microM 4'-(9-acridinylamino)methanesulphon-m-anisidide (m-AMSA) was induced by stepwise increases of drug concentration in the human tumor cell line CALc18 originating from a breast adenocarcinoma. The resistant cell line CALc18/AMSA exhibited a resistance index of 10 and a cross-resistance to other topoisomerase II inhibitors. A 3-fold decrease in the levels of topoisomerase II decatenating activity was found in CALc18/AMSA cells. By contrast, topoisomerase I activity was increased by about 3-fold in resistant cells. Interestingly this line was hypersensitive to camptothecin, a specific inhibitor of topoisomerase I. Restriction endonuclease patterns of the topoisomerase I and topoisomerase II loci were found to be identical in CALc18/AMSA and CALc18 with no evidence of gene amplification and rearrangements. Alkaline elution of m-AMSA-treated cells showed that DNA single strand breaks and DNA-protein crosslinks were decreased in CALc18/AMSA. The DNA lesions also obtained in m-AMSA-treated nuclei indicated that no drug uptake modification occurred in both cells. Moreover, the in vitro m-AMSA-induced DNA cleavage per unit of decatenating activity and the inhibitory effects of antitumoral drugs on decatenation were not found to be different with topoisomerase II from sensitive or resistant cells. However the specific cleavage induced by m-AMSA/per mg of crude protein from resistant cells was 2 to 3 times decreased. Multidrug resistance gene transcripts were not detected while levels of acidic glutathione S transferase mRNA were found to be 8 to 10-fold greater in resistant than in sensitive cell line with no amplification of the gene. In conclusion, the diminution of topoisomerase II activity and the increase of both topoisomerase I and acidic glutathione S transferase transcripts could contribute to the resistant phenotype of these breast cancer cells.
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Affiliation(s)
- D Lefevre
- Laboratoire de Pharmacologie Clinique et Moléculaire, Institut Gustave Roussy, Villejuif, France
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18
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Bailly C, OhUigin C, Rivalle C, Bisagni E, Hénichart JP, Waring MJ. Sequence-selective binding of an ellipticine derivative to DNA. Nucleic Acids Res 1990; 18:6283-91. [PMID: 2173825 PMCID: PMC332493 DOI: 10.1093/nar/18.21.6283] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
The DNA sequence specificity of an ellipticine derivative bearing an aminoalkyl side chain has been determined by a variety of footprinting methods. The drug exhibits sequence selective binding and discriminates against runs of adenines or thymines. Binding is shown to occur at various sequences with a preference for GC rich regions of DNA. A large enhancement of DNAase I and of hydroxyl radical cleavage in regions rich in A's or T's is observed together with hyperreactivity of adenines towards diethylpyrocarbonate in the presence of drug. This indicates the occurrence of drug-induced changes in critical conformational features of DNA. The total absence of hyperreactivity of guanine residues towards diethylpyrocarbonate appears to be related to the sequence selectivity of drug binding. No alteration of the dimethyl sulphate and methylene blue-induced cleavage of DNA is observed. Irradiation of ellipticine derivative-DNA complexes with UV light followed by alkali treatment leads to selective photocleavage at guanine residues, consistent with the deduced degree of selectivity of the binding reaction.
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Affiliation(s)
- C Bailly
- Department of Pharmacology, University of Cambridge, UK
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19
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Capranico G, Jaxel C, Roberge M, Kohn KW, Pommier Y. Nucleosome positioning as a critical determinant for the DNA cleavage sites of mammalian DNA topoisomerase II in reconstituted simian virus 40 chromatin. Nucleic Acids Res 1990; 18:4553-9. [PMID: 2167470 PMCID: PMC331276 DOI: 10.1093/nar/18.15.4553] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We have assessed the ability of nucleosomes to influence the formation of mammalian topoisomerase II-DNA complexes by mapping the sites of cleavage induced by four unrelated topoisomerase II inhibitors in naked versus nucleosome-reconstituted SV40 DNA. DNA fragments were reconstituted with histone octamers from HeLa cells by the histone exchange method. Nucleosome positions were determined by comparing micrococcal nuclease cleavage patterns of nucleosome-reconstituted and naked DNA. Three types of DNA regions were defined: 1) regions with fixed nucleosome positioning; 2) regions lacking regular nucleosome phasing; and 3) a region around the replication origin (from position 5100 to 600) with no detectable nucleosomes. Topoisomerase II cleavage sites were suppressed in nucleosomes and persisted or were enhanced in linker DNA and in the nucleosome-free region around the replication origin. Incubation of reconstituted chromatin with topoisomerase II protected nucleosome-free regions from micrococcal nuclease cleavage without changing the overall micrococcal nuclease cleavage pattern. Thus, the present results indicate that topoisomerase II binds preferentially to nucleosome-free DNA and that the presence of nucleosomes at preferred DNA sequences influences drug-induced DNA breaks by topoisomerase II inhibitors.
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Affiliation(s)
- G Capranico
- Division of Cancer Treatment, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892
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20
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Abstract
Topoisomerase enzymes--found in prokaryotes to human cells--control conformational changes in DNA and aid the orderly progression of DNA replication, gene transcription and the separation of daughter chromosomes at cell division. Several classes of anti-cancer drugs are now recognised as topoisomerase poisons because of their ability to trap topoisomerase molecules on DNA as 'cleavable complexes'. Understanding how drugs generate such complexes and why they are toxic to actively growing cancer cells is a major challenge for the development of modern approaches to chemotherapy.
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Affiliation(s)
- P J Smith
- MRC Clinical Oncology, Cambridge, UK
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21
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Gribble GW. Chapter 7 Synthesis and Antitumor Activity of Ellipticine Alkaloids and Related Compounds. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/s0099-9598(08)60169-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/16/2023]
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22
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Schneider E, Hsiang YH, Liu LF. DNA topoisomerases as anticancer drug targets. ADVANCES IN PHARMACOLOGY (SAN DIEGO, CALIF.) 1990; 21:149-83. [PMID: 2176094 DOI: 10.1016/s1054-3589(08)60342-7] [Citation(s) in RCA: 142] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- E Schneider
- Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205
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23
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Schaack J, Schedl P, Shenk T. Topoisomerase I and II cleavage of adenovirus DNA in vivo: both topoisomerase activities appear to be required for adenovirus DNA replication. J Virol 1990; 64:78-85. [PMID: 2152835 PMCID: PMC249049 DOI: 10.1128/jvi.64.1.78-85.1990] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Sites of topoisomerase I and II cleavage across large portions of the adenovirus type 5 genome were mapped by using the drugs camptothecin and VM26, respectively. These drugs prolong the half-lives of the covalent DNA-protein intermediates in which the DNA is transiently cleaved, and so treatment with protein denaturants after exposure to the drugs leads to DNA strand scission at the site of topoisomerase cleavage. Strong topoisomerase II cleavage sites occurred in clusters throughout the regions examined, including both transcribed regions and transcriptional control regions. The efficiency of topoisomerase II cleavage increased as the rate of adenovirus DNA replication increased and then decreased with the decreasing rate of replication late in the infection cycle. The increase was not dependent on expression of the E1A gene, whose products activate transcription of the early viral genes. Positions of topoisomerase II cleavage sites did not vary during the infection. Topoisomerase I cleavage sites were also found throughout the examined regions, with the strongest sites occurring near the ends of the transcription units. Topoisomerase I cleavage in the E1 region occurred much more frequently than topoisomerase II cleavage, was not dependent on E1A gene expression, and remained at a similar level from the early viral phase into the late viral phase. Treatment of infected cells with either drug prevented efficient replication of adenovirus DNA. Inhibition of topoisomerase I activity led to an immediate cessation of adenovirus DNA replication, while inhibition of topoisomerase II blocked replication only after completion of approximately one additional round.
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Affiliation(s)
- J Schaack
- Department of Biology, Howard Hughes Medical Institute, Princeton, New Jersey
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24
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25
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Multon E, Riou JF, LeFevre D, Ahomadegbe JC, Riou G. Topoisomerase II-mediated DNA cleavage activity induced by ellipticines on the human tumor cell line N417. Biochem Pharmacol 1989; 38:2077-86. [PMID: 2544183 DOI: 10.1016/0006-2952(89)90060-9] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Ellipticine derivatives have been shown to induce DNA strand breaks by trapping DNA-topoisomerase II (Topo II) in an intermediary covalent complex between Topo II and DNA which could be related to their cytotoxic effects. We report here that Celiptium and Detalliptinium, two ellipticine derivatives clinically used for their antitumoral properties against breast cancer, exhibit the highest in vitro activity on Topo II DNA cleavage reaction and decatenation among a series of 14 ellipticine derivatives. The in vitro cleavage site specificity in pBR 322 plasmid DNA and in a human c-myc gene inserted in a lambda phage DNA is identical for both ellipticines, but different from m-AMSA, another Topo II related antitumoral agent. Recently, it has been shown that the ellipticine derivative Celiptium presents a strong cytotoxic activity in vitro on different human tumors including small cell lung carcinoma (SCLC). However, the studies that involved Topo II as a target for ellipticine derivatives have been performed only by using animal tumor cell lines. Therefore we have studied the in vivo DNA cleavage activity of Celiptium and Detalliptinium on a human SCLC cell line, NCI N417, comparatively to that obtained with m-AMSA. The respective IC50 on cell growth are 9, 8 and 1 microM for Celiptium, Detalliptinium and m-AMSA, respectively. Using the alkaline elution technique, we have observed that Celiptium and Detalliptinium exhibit a weak cleavage activity on genomic DNA from whole cells. The ellipticines are about 50 times less potent than m-AMSA in inducing DNA strand breaks. Analysis of in vivo c-myc gene cleavage by Southern blot hybridization also demonstrates a lack of activity of the ellipticine derivatives as no gene cleavage could be detected up to 50 microM of the drug. With m-AMSA, c-myc gene cleavage is detected at a concentration of 0.2 microM, which indicates that this methodology is less sensitive in detecting DNA strand breaks than is the alkaline elution. Further studies of the drug effect on isolated nuclei by alkaline elution also show that the DNA cleavage activity of Celiptium and Detalliptinium is increased when compared to whole cells. Our data indicate that these two drugs have a weaker cytotoxic effect than m-AMSA on NCI N417 cell line, due to a limited access to the cell nucleus rather than to a lack of activity on Topo II as assessed by in vitro and isolated nuclei experiments.
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Affiliation(s)
- E Multon
- Laboratoire de Pharmacologie Clinique, Moléculaire Institut Gustave Roussy, Villejuif, France
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26
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Schneider E, Hutchins AM, Darkin SJ, Lawson PA, Ralph RK. Relationship between sensitivity to 4'-(9-acridinylamino)methanesulfon-m-anisidide and DNA topoisomerase II in a cold-sensitive cell-cycle mutant of a murine mastocytoma cell line. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 951:85-97. [PMID: 2847799 DOI: 10.1016/0167-4781(88)90028-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The cold-sensitive (proliferating at 39.5 degrees C, reversibly arrested in GI-phase at 33 degrees C) cell-cycle mutant 21-Fb of the murine mastocytoma cell line P815 was used to study the effect of amsacrine on non-cycling cells. The sensitivity of arrested 21-Fb cells decreased less than 2-fold in cell survival experiments when compared to proliferating cells. In contrast, DNA breakage and stimulation of protein-DNA complex formation in intact or lysed cells was reduced approx. 10-fold in arrested cells and DNA topoisomerase II activity in arrested cells was only 5% of the activity in proliferating cells. Thus, there was no correlation between cell survival and DNA damage or DNA topoisomerase II activity in drug-treated cells.
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Affiliation(s)
- E Schneider
- Department of Cellular and Molecular Biology, University of Auckland, New Zealand
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27
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Schneider E, Darkin SJ, Robbie MA, Wilson WR, Ralph RK. Mechanism of resistance of non-cycling mammalian cells to 4'-[9-acridinylamino]methanesulphon-m-anisidide: role of DNA topoisomerase II in log- and plateau-phase CHO cells. BIOCHIMICA ET BIOPHYSICA ACTA 1988; 949:264-72. [PMID: 2831986 DOI: 10.1016/0167-4781(88)90151-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
CHO-AA8 cells were used as a model system to study the role of DNA topoisomerase II in the resistance of non-cycling cells to amsacrine. Plateau-phase AA8 cells have previously been shown to be resistant to amsacrine and to contain fewer DNA breaks than log-phase cells after drug treatment (Robbie, M.A., Baguley, B.C., Denny, W.A., Gavin, J.R. and Wilson, W.R. (1988) Cancer Res., in press). The phage P4-unknotting activity of nuclear extracts decreased 2-fold when AA8 cells entered into the non-cycling state, but there was no difference in sensitivity to amsacrine between log- and plateau-phase nuclear extracts. Drug stimulation of protein-DNA complex formation was similar in whole cells, isolated nuclei and nuclear extracts from either log- or plateau-phase cells. However, stimulation of complex formation in cells, nuclei or nuclear extracts was approx. 4-fold lower in plateau-phase than in log-phase. The data presented suggested that drug-enzyme interaction was altered in plateau-phase cells.
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Affiliation(s)
- E Schneider
- Department of Cellular and Molecular Biology, University of Auckland, New Zealand
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28
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Glisson BS, Ross WE. DNA topoisomerase II: a primer on the enzyme and its unique role as a multidrug target in cancer chemotherapy. Pharmacol Ther 1987; 32:89-106. [PMID: 3037573 DOI: 10.1016/0163-7258(87)90054-4] [Citation(s) in RCA: 91] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Based on the weight of evidence accrued in the past eight years, there is little question that the nuclear enzyme, topoisomerase II, serves as a common intracellular target for the cytotoxic effect of drugs of widely varying structure. The enzyme appears to be unique as a chemotherapy target in that it is recruited into a lethal process under the influence of drug. Its role contrasts sharply with other more classical chemotherapy targets, such as dihydrofolate reductase, whose activity must be successfully inhibited for the expression of cytotoxicity. Resistance to inhibitors of this enzyme frequently results from marked elevations in intracellular enzyme content. In contrast, the presence of topoisomerase is required for drug effect, and, in general, the greater the cellular content of the enzyme, the more sensitive the cell will be to these agents. However, important issues remain unresolved. The biochemical events that are initiated by cleavable complex formation and result in cell death must be more fully defined. It is likely a better understanding of the drug-enzyme interaction will be required for rational drug development. Finally, those aspects of the drug-topoisomerase interaction that confer therapeutic selectivity and/or clinical resistance are of paramount importance if the phenomenon is ever to be fully exploited.
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29
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Riou JF, Vilarem MJ, Larsen CJ, Riou G. Characterization of the topoisomerase II-induced cleavage sites in the c-myc proto-oncogene. In vitro stimulation by the antitumoral intercalating drug mAMSA. Biochem Pharmacol 1986; 35:4409-13. [PMID: 3024649 DOI: 10.1016/0006-2952(86)90756-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
In an attempt to get an insight into the activity of mAMSA (a DNA topoisomerase II-mediated drug) on the human proto-oncogene c-myc, an in vitro system consisting of purified calf thymus DNA topoisomerase II and a c-myc DNA inserted in lambda phage was utilized. The occurrence of discrete bands, detected by hybridization of Southern blots with appropriate c-myc probes, indicated the presence of cleavage sites in the sole presence of DNA topoisomerase II. The band intensity increased in the presence of mAMSA, while no significant difference occurred in the cleavage pattern. The location of the cleavage sites along the c-myc locus revealed a striking correspondence with that of some DNase hypersensitive sites. These results indicate that DNA topoisomerase II is most certainly implicated in the mAMSA activity and that the drug stimulates the topoisomerase II cleaving activity at specific sites, which may be involved in the biological activity of the drug.
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