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1
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Li XL, Li M, Yang H, Tian J, Shi ZW, Wang LZ, Song K. Chronic myelogenous leukemia secondary to colon cancer: A case report. World J Gastrointest Oncol 2025; 17:102021. [DOI: 10.4251/wjgo.v17.i4.102021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2024] [Revised: 01/26/2025] [Accepted: 02/18/2025] [Indexed: 03/25/2025] Open
Abstract
BACKGROUND Colon cancer is a common malignancy of the digestive tract. An estimated 1148515 new cases of colon cancer were reported in 2020 worldwide. Chronic myeloid leukemia (CML) is a malignant tumor formed by the clonal proliferation of bone marrow hematopoietic stem cells, with an annual incidence rate of 1-2 cases per 100000 people worldwide. Leukemia can be secondary to solid tumors, and vice versa. Reports on CML secondary malignant tumors account for 8.7% but CML secondary to malignancy is extremely rare. Therapy-related CML is a rare but potentially fatal adverse event of chemotherapy or radiotherapy. Herein, we report a case of CML with colon cancer and discuss this unique patient population. Our findings can provide effective raw data and guidance for the diagnosis of this clinical disease.
CASE SUMMARY A 61-year-old male patient attended our hospital due to leukocytosis for 5 days. In February 2020, the patient was diagnosed with colon cancer and underwent radical surgery and conventional chemotherapy with a stable condition. He was diagnosis was CML-chronic phase (Sokal score of 0.72) after examination. He was treated with imatinib (400 mg daily). When his conditions improved, the patient was discharged from our hospital and visited the outpatient department for follow-up twice a month.
CONCLUSION CML in patients with colon cancer is extremely rare. Secondary hematological tumors may be multifactorial, and the exact mechanism is currently unknown. Owing to the slow progression of the disease, patients with CML show no symptoms in the early stage. However, with disease progression, obvious but non-specific symptoms may appear, including fever, anemia, bleeding tendency, and hypertrophy. Therefore, complete blood count monitoring for routine examination is recommended after cancer treatment for early detection of occult hematological tumors.
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Affiliation(s)
- Xiao-Lan Li
- Department of Hematology, The First Affiliated Hospital of Jishou University, Jishou 416000, Hunan Province, China
| | - Min Li
- Department of Pharmacy, The First Affiliated Hospital of Jishou University, Jishou 416000, Hunan Province, China
| | - Hua Yang
- Department of Hematology, The First Affiliated Hospital of Jishou University, Jishou 416000, Hunan Province, China
| | - Juan Tian
- Department of Hematology, The First Affiliated Hospital of Jishou University, Jishou 416000, Hunan Province, China
| | - Zi-Wei Shi
- Department of Hematology, The First Affiliated Hospital of Jishou University, Jishou 416000, Hunan Province, China
| | - Ling-Zhi Wang
- Department of Pharmacy, The First Affiliated Hospital of Jishou University, Jishou 416000, Hunan Province, China
| | - Kui Song
- Department of Hematology, The First Affiliated Hospital of Jishou University, Jishou 416000, Hunan Province, China
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Nitiss KC, Bandak A, Berger JM, Nitiss JL. Genome Instability Induced by Topoisomerase Misfunction. Int J Mol Sci 2024; 25:10247. [PMID: 39408578 PMCID: PMC11477040 DOI: 10.3390/ijms251910247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2024] [Revised: 09/19/2024] [Accepted: 09/20/2024] [Indexed: 10/20/2024] Open
Abstract
Topoisomerases alter DNA topology by making transient DNA strand breaks (DSBs) in DNA. The DNA cleavage reaction mechanism includes the formation of a reversible protein/DNA complex that allows rapid resealing of the transient break. This mechanism allows changes in DNA topology with minimal risks of persistent DNA damage. Nonetheless, small molecules, alternate DNA structures, or mutations in topoisomerase proteins can impede the resealing of the transient breaks, leading to genome instability and potentially cell death. The consequences of high levels of enzyme/DNA adducts differ for type I and type II topoisomerases. Top1 action on DNA containing ribonucleotides leads to 2-5 nucleotide deletions in repeated sequences, while mutant Top1 enzymes can generate large deletions. By contrast, small molecules that target Top2, or mutant Top2 enzymes with elevated levels of cleavage lead to small de novo duplications. Both Top1 and Top2 have the potential to generate large rearrangements and translocations. Thus, genome instability due to topoisomerase mis-function is a potential pathogenic mechanism especially leading to oncogenic progression. Recent studies support the potential roles of topoisomerases in genetic changes in cancer cells, highlighting the need to understand how cells limit genome instability induced by topoisomerases. This review highlights recent studies that bear on these questions.
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Affiliation(s)
- Karin C. Nitiss
- Pharmaceutical Sciences Department, University of Illinois Chicago, Rockford, IL 61107, USA;
| | - Afif Bandak
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 20215, USA; (A.B.); (J.M.B.)
| | - James M. Berger
- Department of Biophysics and Biophysical Chemistry, Johns Hopkins School of Medicine, Baltimore, MD 20215, USA; (A.B.); (J.M.B.)
| | - John L. Nitiss
- Pharmaceutical Sciences Department, University of Illinois Chicago, Rockford, IL 61107, USA;
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3
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Cowell IG, Austin CA. Myeloperoxidase inhibition protects bone marrow mononuclear cells from DNA damage induced by the TOP2 poison anti-cancer drug etoposide. FEBS Open Bio 2024; 14:1001-1010. [PMID: 38531625 PMCID: PMC11148113 DOI: 10.1002/2211-5463.13799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2024] [Revised: 02/13/2024] [Accepted: 03/20/2024] [Indexed: 03/28/2024] Open
Abstract
Myeloperoxidase (MPO) is found almost exclusively in granulocytes and immature myeloid cells. It plays a key role in the innate immune system, catalysing the formation of reactive oxygen species that are important in anti-microbial action, but MPO also oxidatively transforms the topoisomerase II (TOP2) poison etoposide to chemical forms that have elevated DNA damaging properties. TOP2 poisons such as etoposide are widely used anti-cancer drugs, but they are linked to cases of secondary acute myeloid leukaemias through a mechanism that involves DNA damage and presumably erroneous repair leading to leukaemogenic chromosome translocations. This leads to the possibility that myeloperoxidase inhibitors could reduce the rate of therapy-related leukaemia by protecting haematopoietic cells from TOP2 poison-mediated genotoxic damage while preserving the anti-cancer efficacy of the treatment. We show here that myeloperoxidase inhibition reduces etoposide-induced TOP2B-DNA covalent complexes and resulting DNA double-strand break formation in primary ex vivo expanded CD34+ progenitor cells and unfractionated bone marrow mononuclear cells. Since MPO inhibitors are currently being developed as anti-inflammatory agents this raises the possibility that repurposing of these potential new drugs could provide a means of suppressing secondary acute myeloid leukaemias associated with therapies containing TOP2 poisons.
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4
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Zhang W, Gou P, Dupret JM, Chomienne C, Rodrigues-Lima F. Etoposide, an anticancer drug involved in therapy-related secondary leukemia: Enzymes at play. Transl Oncol 2021; 14:101169. [PMID: 34243013 PMCID: PMC8273223 DOI: 10.1016/j.tranon.2021.101169] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 06/29/2021] [Indexed: 01/13/2023] Open
Abstract
Etoposide is a semi-synthetic glycoside derivative of podophyllotoxin, also known as VP-16. It is a widely used anticancer medicine in clinics. Unfortunately, high doses or long-term etoposide treatment can induce therapy-related leukemia. The mechanism by which etoposide induces secondary hematopoietic malignancies is still unclear. In this article, we review the potential mechanisms of etoposide induced therapy-related leukemia. Etoposide related leukemogenesis is known to depend on reactive oxidative metabolites of etoposide, notably etoposide quinone, which interacts with cellular proteins such as topoisomerases II (TOP2), CREB-binding protein (CREBBP), and T-Cell Protein Tyrosine Phosphatase (TCPTP). CYP3A4 and CYP3A5 metabolize etoposide to etoposide catechol, which readily oxidizes to etoposide quinone. As a poison of TOP2 enzymes, etoposide and its metabolites induce DNA double-stranded breaks (DSB), and the accumulation of DSB triggers cell apoptosis. If the cell survives, the DSB gives rise to the likelihood of faulty DNA repair events. The gene translocation could occur in mixed-lineage leukemia (MLL) gene, which is well-known in leukemogenesis. Recently, studies have revealed that etoposide metabolites, especially etoposide quinone, can covalently bind to cysteines residues of CREBBP and TCPTP enzymes, . This leads to enzyme inhibition and further affects histone acetylation and phosphorylation of the JAK-STAT pathway, thus putatively altering the proliferation and differentiation of hematopoietic stem cells (HSC). In brief, current studies suggest that etoposide and its metabolites contribute to etoposide therapy-related leukemia through TOP2 mediated DSB and impairs specific enzyme activity, such as CREBBP and TCPTP.
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Affiliation(s)
- Wenchao Zhang
- Université de Paris, BFA, UMR 8251, CNRS, Paris F-75013, France.
| | - Panhong Gou
- Inserm UMR-S1131, Université de Paris, IRSL, Hôpital Saint-Louis, Paris, France
| | | | - Christine Chomienne
- Inserm UMR-S1131, Université de Paris, IRSL, Hôpital Saint-Louis, Paris, France; Service de Biologie Cellulaire, Assistance Publique des Hôpitaux de Paris (AP-HP), Hôpital Saint Louis, Paris, France
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5
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Vann KR, Oviatt AA, Osheroff N. Topoisomerase II Poisons: Converting Essential Enzymes into Molecular Scissors. Biochemistry 2021; 60:1630-1641. [PMID: 34008964 PMCID: PMC8209676 DOI: 10.1021/acs.biochem.1c00240] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The extensive length, compaction, and interwound nature of DNA, together with its controlled and restricted movement in eukaryotic cells, create a number of topological issues that profoundly affect all of the functions of the genetic material. Topoisomerases are essential enzymes that modulate the topological structure of the double helix, including the regulation of DNA under- and overwinding and the removal of tangles and knots from the genome. Type II topoisomerases alter DNA topology by generating a transient double-stranded break in one DNA segment and allowing another segment to pass through the DNA gate. These enzymes are involved in a number of critical nuclear processes in eukaryotic cells, such as DNA replication, transcription, and recombination, and are required for proper chromosome structure and segregation. However, because type II topoisomerases generate double-stranded breaks in the genetic material, they also are intrinsically dangerous enzymes that have the capacity to fragment the genome. As a result of this dualistic nature, type II topoisomerases are the targets for a number of widely prescribed anticancer drugs. This article will describe the structure and catalytic mechanism of eukaryotic type II topoisomerases and will go on to discuss the actions of topoisomerase II poisons, which are compounds that stabilize DNA breaks generated by the type II enzyme and convert these essential enzymes into "molecular scissors." Topoisomerase II poisons represent a broad range of structural classes and include anticancer drugs, dietary components, and environmental chemicals.
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Affiliation(s)
- Kendra R Vann
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Alexandria A Oviatt
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
| | - Neil Osheroff
- Departments of Biochemistry and Medicine (Hematology/Oncology), Vanderbilt University School of Medicine, Nashville, Tennessee 37232, United States
- VA Tennessee Valley Healthcare System, Nashville, Tennessee 37212, United States
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6
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Murphy MB, Kumar P, Bradley AM, Barton CE, Deweese JE, Mercer SL. Synthesis and evaluation of etoposide and podophyllotoxin analogs against topoisomerase IIα and HCT-116 cells. Bioorg Med Chem 2020; 28:115773. [PMID: 33035756 DOI: 10.1016/j.bmc.2020.115773] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 08/18/2020] [Accepted: 09/09/2020] [Indexed: 12/21/2022]
Abstract
Etoposide is a widely-used anticancer agent that targets human type II topoisomerases. Evidence suggests that metabolism of etoposide in myeloid progenitor cells is associated with translocations involved in leukemia development. Previous studies suggest halogenation at the C-2' position of etoposide reduces metabolism. Halogens were introduced into the C-2' position by electrophilic aromatic halogenation onto etoposide (ETOP, 1), podophyllotoxin (PPT, 2), and 4-dimethylepipodophyllotoxin (DMEP, 3), and to bridge the gap of knowledge regarding the activity of these metabolically stable analogs. Five halogenated analogs (6-10) were synthesized. Analogs 8-10 displayed variable ability to inhibit DNA relaxation. Analog 9 was the only analog to show concentration-dependent enhancement of Top2-mediated DNA cleavage. Dose response assay results indicated that 8 and 10 were most effective at decreasing the viability of HCT-116 and A549 cancer cell lines in culture. Flow cytometry with 8 and 10 in HCT-116 cells provide evidence of sub-G1 cell populations indicative of apoptosis. Taken together, these results indicate C-2' halogenation of etoposide and its precursors, although metabolically stable, decreases overall activity relative to etoposide.
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Affiliation(s)
- Matthew B Murphy
- Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy and Health Sciences, One University, Park Drive, Nashville, TN 37204, USA
| | - Priyanka Kumar
- Department of Biology, Belmont University, 1900 Belmont Boulevard, Nashville, TN 37212, USA
| | - Amber M Bradley
- Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy and Health Sciences, One University, Park Drive, Nashville, TN 37204, USA
| | - Christopher E Barton
- Department of Biology, Belmont University, 1900 Belmont Boulevard, Nashville, TN 37212, USA
| | - Joseph E Deweese
- Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy and Health Sciences, One University, Park Drive, Nashville, TN 37204, USA; Departments of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37235, USA
| | - Susan L Mercer
- Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy and Health Sciences, One University, Park Drive, Nashville, TN 37204, USA; Departments of Pharmacology, Vanderbilt University School of Medicine, Nashville, TN 37235, USA.
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7
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Geisen SM, Sturla SJ. Can Foods or Herbs Alter the Bioavailability of Chemotherapy Drugs? ACS Pharmacol Transl Sci 2019; 2:143-146. [DOI: 10.1021/acsptsci.9b00007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Susanne M. Geisen
- Department of Health Sciences and Technology, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
| | - Shana J. Sturla
- Department of Health Sciences and Technology, ETH Zurich, Schmelzbergstrasse 9, 8092 Zurich, Switzerland
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8
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Jamieson GC, Fox JA, Poi M, Strickland SA. Molecular and Pharmacologic Properties of the Anticancer Quinolone Derivative Vosaroxin: A New Therapeutic Agent for Acute Myeloid Leukemia. Drugs 2017; 76:1245-1255. [PMID: 27484675 PMCID: PMC4989016 DOI: 10.1007/s40265-016-0614-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Vosaroxin is a first-in-class anticancer quinolone derivative that targets topoisomerase II and induces site-selective double-strand breaks in DNA, leading to tumor cell apoptosis. Vosaroxin has chemical and pharmacologic characteristics distinct from other topoisomerase II inhibitors due to its quinolone scaffold. The efficacy and safety of vosaroxin in combination with cytarabine were evaluated in patients with relapsed/refractory acute myeloid leukemia (AML) in a phase III, randomized, multicenter, double-blind, placebo-controlled study (VALOR). In this study, the addition of vosaroxin produced a 1.4-month improvement in median overall survival (OS; 7.5 months with vosaroxin/cytarabine vs. 6.1 months with placebo/cytarabine; hazard ratio [HR] 0.87, 95 % confidence interval [CI] 0.73−1.02; unstratified log-rank p\documentclass[12pt]{minimal}
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\begin{document}$$=$$\end{document}= 0.039), two AML patient groups that typically have poor prognosis. Here we review the chemical and pharmacologic properties of vosaroxin, how these properties are distinct from those of currently available topoisomerase II inhibitors, how they may contribute to the efficacy and safety profile observed in the VALOR trial, and the status of clinical development of vosaroxin for treatment of AML.
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Affiliation(s)
| | - Judith A Fox
- Sunesis Pharmaceuticals, Inc., South San Francisco, CA, USA
| | - Ming Poi
- College of Pharmacy, Ohio State University, Columbus, OH, USA
| | - Stephen A Strickland
- Division of Hematology/Oncology, Department of Medicine, Vanderbilt University, 2220 Pierce Avenue, 777 Preston Research Building, Nashville, TN, 37232, USA.
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9
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Atwal M, Lishman EL, Austin CA, Cowell IG. Myeloperoxidase Enhances Etoposide and Mitoxantrone-Mediated DNA Damage: A Target for Myeloprotection in Cancer Chemotherapy. Mol Pharmacol 2017; 91:49-57. [PMID: 27974636 PMCID: PMC5198516 DOI: 10.1124/mol.116.106054] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 11/08/2016] [Indexed: 01/17/2023] Open
Abstract
Myeloperoxidase is expressed exclusively in granulocytes and immature myeloid cells and transforms the topoisomerase II (TOP2) poisons etoposide and mitoxantrone to chemical forms that have altered DNA damaging properties. TOP2 poisons are valuable and widely used anticancer drugs, but they are associated with the occurrence of secondary acute myeloid leukemias. These factors have led to the hypothesis that myeloperoxidase inhibition could protect hematopoietic cells from TOP2 poison-mediated genotoxic damage and, therefore, reduce the rate of therapy-related leukemia. We show here that myeloperoxidase activity leads to elevated accumulation of etoposide- and mitoxantrone-induced TOP2A and TOP2B-DNA covalent complexes in cells, which are converted to DNA double-strand breaks. For both drugs, the effect of myeloperoxidase activity was greater for TOP2B than for TOP2A. This is a significant finding because TOP2B has been linked to genetic damage associated with leukemic transformation, including etoposide-induced chromosomal breaks at the MLL and RUNX1 loci. Glutathione depletion, mimicking in vivo conditions experienced during chemotherapy treatment, elicited further MPO-dependent increase in TOP2A and especially TOP2B-DNA complexes and DNA double-strand break formation. Together these results support targeting myeloperoxidase activity to reduce genetic damage leading to therapy-related leukemia, a possibility that is enhanced by the recent development of novel specific myeloperoxidase inhibitors for use in inflammatory diseases involving neutrophil infiltration.
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Affiliation(s)
- Mandeep Atwal
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne. United Kingdom
| | - Emma L Lishman
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne. United Kingdom
| | - Caroline A Austin
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne. United Kingdom
| | - Ian G Cowell
- Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne. United Kingdom
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10
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11
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Montecucco A, Zanetta F, Biamonti G. Molecular mechanisms of etoposide. EXCLI JOURNAL 2015; 14:95-108. [PMID: 26600742 PMCID: PMC4652635 DOI: 10.17179/excli2015-561] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Accepted: 10/24/2014] [Indexed: 12/21/2022]
Abstract
Etoposide derives from podophyllotoxin, a toxin found in the American Mayapple. It was first synthesized in 1966 and approved for cancer therapy in 1983 by the U.S. Food and Drug Administration (Hande, 1998[25]). Starting from 1980s several studies demonstrated that etoposide targets DNA topoisomerase II activities thus leading to the production of DNA breaks and eliciting a response that affects several aspects of cell metabolisms. In this review we will focus on molecular mechanisms that account for the biological effect of etoposide.
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Affiliation(s)
| | - Francesca Zanetta
- Istituto di Genetica Molecolare, CNR, via Abbiategrasso 207, Pavia ; Dipartimento di Biologia e Biotecnologia, Università degli Studi di Pavia, via Ferrata 9, Pavia, Italy
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12
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Lindsey RH, Pendleton M, Ashley RE, Mercer SL, Deweese JE, Osheroff N. Catalytic core of human topoisomerase IIα: insights into enzyme-DNA interactions and drug mechanism. Biochemistry 2014; 53:6595-602. [PMID: 25280269 PMCID: PMC4204876 DOI: 10.1021/bi5010816] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Coordination between the N-terminal gate and the catalytic core of topoisomerase II allows the proper capture, cleavage, and transport of DNA during the catalytic cycle. Because the activities of these domains are tightly linked, it has been difficult to discern their individual contributions to enzyme-DNA interactions and drug mechanism. To further address the roles of these domains, we analyzed the activity of the catalytic core of human topoisomerase IIα. The catalytic core and the wild-type enzyme both maintained higher levels of cleavage with negatively (as compared to positively) supercoiled plasmid, indicating that the ability to distinguish supercoil handedness is embedded within the catalytic core. However, the catalytic core alone displayed little ability to cleave DNA substrates that did not intrinsically provide the enzyme with a transport segment (i.e., substrates that did not contain crossovers). Finally, in contrast to interfacial topoisomerase II poisons, covalent poisons did not enhance DNA cleavage mediated by the catalytic core. This distinction allowed us to further characterize the mechanism of etoposide quinone, a drug metabolite that functions primarily as a covalent poison. Etoposide quinone retained some ability to enhance DNA cleavage mediated by the catalytic core, indicating that it still can function as an interfacial poison. These results further define the distinct contributions of the N-terminal gate and the catalytic core to topoisomerase II function. The catalytic core senses the handedness of DNA supercoils during cleavage, while the N-terminal gate is critical for capturing the transport segment and for the activity of covalent poisons.
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Affiliation(s)
- R Hunter Lindsey
- Department of Biochemistry, ‡Department of Pharmacology, and §Department of Medicine (Hematology/Oncology), Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
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Smith NA, Byl JAW, Mercer SL, Deweese JE, Osheroff N. Etoposide quinone is a covalent poison of human topoisomerase IIβ. Biochemistry 2014; 53:3229-36. [PMID: 24766193 PMCID: PMC4033626 DOI: 10.1021/bi500421q] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
![]()
Etoposide is a topoisomerase II poison
that is utilized to treat
a broad spectrum of human cancers. Despite its wide clinical use,
2–3% of patients treated with etoposide eventually develop
treatment-related acute myeloid leukemias (t-AMLs) characterized by
rearrangements of the MLL gene. The molecular basis
underlying the development of these t-AMLs is not well understood;
however, previous studies have implicated etoposide metabolites (i.e.,
etoposide quinone) and topoisomerase IIβ in the leukemogenic
process. Although interactions between etoposide quinone and topoisomerase
IIα have been characterized, the effects of the drug metabolite
on the activity of human topoisomerase IIβ have not been reported.
Thus, we examined the ability of etoposide quinone to poison human
topoisomerase IIβ. The quinone induced ∼4 times more
enzyme-mediated DNA cleavage than did the parent drug. Furthermore,
the potency of etoposide quinone was ∼2 times greater against
topoisomerase IIβ than it was against topoisomerase IIα,
and the drug reacted ∼2–4 times faster with the β
isoform. Etoposide quinone induced a higher ratio of double- to single-stranded
breaks than etoposide, and its activity was less dependent on ATP.
Whereas etoposide acts as an interfacial topoisomerase II poison,
etoposide quinone displayed all of the hallmarks of a covalent poison:
the activity of the metabolite was abolished by reducing agents, and
the compound inactivated topoisomerase IIβ when it was incubated
with the enzyme prior to the addition of DNA. These results are consistent
with the hypothesis that etoposide quinone contributes to etoposide-related
leukemogenesis through an interaction with topoisomerase IIβ.
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Affiliation(s)
- Nicholas A Smith
- Departments of †Biochemistry, ‡Medicine (Hematology/Oncology), and §Pharmacology, Vanderbilt University School of Medicine , Nashville, Tennessee 37232-0146, United States
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14
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Ketron AC, Osheroff N. Phytochemicals as Anticancer and Chemopreventive Topoisomerase II Poisons. PHYTOCHEMISTRY REVIEWS : PROCEEDINGS OF THE PHYTOCHEMICAL SOCIETY OF EUROPE 2014; 13:19-35. [PMID: 24678287 PMCID: PMC3963363 DOI: 10.1007/s11101-013-9291-7] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Phytochemicals are a rich source of anticancer drugs and chemopreventive agents. Several of these chemicals appear to exert at least some of their effects through interactions with topoisomerase II, an essential enzyme that regulates DNA supercoiling and removes knots and tangles from the genome. Topoisomerase II-active phytochemicals function by stabilizing covalent protein-cleaved DNA complexes that are intermediates in the catalytic cycle of the enzyme. As a result, these compounds convert topoisomerase II to a cellular toxin that fragments the genome. Because of their mode of action, they are referred to as topoisomerase II poisons as opposed to catalytic inhibitors. The first sections of this article discuss DNA topology, the catalytic cycle of topoisomerase II, and the two mechanisms (interfacial vs. covalent) by which different classes of topoisomerase II poisons alter enzyme activity. Subsequent sections discuss the effects of several phytochemicals on the type II enzyme, including demethyl-epipodophyllotoxins (semisynthetic anticancer drugs) as well as flavones, flavonols, isoflavones, catechins, isothiocyanates, and curcumin (dietary chemopreventive agents). Finally, the leukemogenic potential of topoisomerase II-targeted phytochemicals is described.
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Affiliation(s)
- Adam C. Ketron
- Department of Biochemistry and the Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 USA
| | - Neil Osheroff
- Departments of Biochemistry and Medicine (Hematology/Oncology) and the Vanderbilt Institute of Chemical Biology, Vanderbilt University School of Medicine, Nashville, Tennessee 37232 USA
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Abstract
Therapy-related leukemia (myelodysplasia and acute myeloid leukemia-t-MDS/AML) is a well-known complication of conventional chemoradiotherapy used to treat a variety of primary malignancies including Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL), acute lymphoblastic leukemia (ALL), sarcoma, and ovarian and testicular cancers. The median time to development of t-MDS/AML is 3-5 years, with the risk decreasing markedly after the first decade. t-MDS/AML is the major cause of non-relapse mortality after autologous hematopoietic cell transplantation (HCT) for HL or NHL. The magnitude of risk of t-MDS/AML is higher, and the latency is shorter after HCT, compared to conventional therapy. Two types of t-MDS/AML are recognized depending on the causative therapeutic exposure: an alkylating agent/radiation-related type and a topoisomerase II inhibitor-related type. Inter-individual variability in the risk for development of t-MDS/AML suggests a role for genetic variation in susceptibility to genotoxic exposures. Treatment of t-MDS/AML with conventional therapy is associated with a uniformly poor prognosis, with a median survival of 6 months. Because of the poor response to conventional chemotherapy, allogeneic HCT is recommended. Current research is focused on developing risk prediction and risk reduction strategies.
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Affiliation(s)
- Smita Bhatia
- Department of Population Sciences, City of Hope Comprehensive Cancer Center, Duarte, CA.
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16
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Pendleton M, Lindsey RH, Felix CA, Grimwade D, Osheroff N. Topoisomerase II and leukemia. Ann N Y Acad Sci 2014; 1310:98-110. [PMID: 24495080 DOI: 10.1111/nyas.12358] [Citation(s) in RCA: 141] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Type II topoisomerases are essential enzymes that modulate DNA under- and overwinding, knotting, and tangling. Beyond their critical physiological functions, these enzymes are the targets for some of the most widely prescribed anticancer drugs (topoisomerase II poisons) in clinical use. Topoisomerase II poisons kill cells by increasing levels of covalent enzyme-cleaved DNA complexes that are normal reaction intermediates. Drugs such as etoposide, doxorubicin, and mitoxantrone are frontline therapies for a variety of solid tumors and hematological malignancies. Unfortunately, their use also is associated with the development of specific leukemias. Regimens that include etoposide or doxorubicin are linked to the occurrence of acute myeloid leukemias that feature rearrangements at chromosomal band 11q23. Similar rearrangements are seen in infant leukemias and are associated with gestational diets that are high in naturally occurring topoisomerase II-active compounds. Finally, regimens that include mitoxantrone and epirubicin are linked to acute promyelocytic leukemias that feature t(15;17) rearrangements. The first part of this article will focus on type II topoisomerases and describe the mechanism of enzyme and drug action. The second part will discuss how topoisomerase II poisons trigger chromosomal breaks that lead to leukemia and potential approaches for dissociating the actions of drugs from their leukemogenic potential.
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Affiliation(s)
- Maryjean Pendleton
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee
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17
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Hasan SK, Barba G, Metzler M, Divona M, Ottone T, Cicconi L, Falini B, Mecucci C, Lo-Coco F. Clustering of genomic breakpoints at the MLL locus in therapy-related acute leukemia with t(4;11)(q21;q23). Genes Chromosomes Cancer 2013; 53:248-54. [PMID: 24310817 DOI: 10.1002/gcc.22135] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2013] [Accepted: 11/18/2013] [Indexed: 12/15/2022] Open
Abstract
Genomic characterization of translocation breakpoints is relevant to identify possible mechanisms underlying their origin. The consistent association of anthracylines (e.g., epirubicin and idarubicin) in inducing therapy-related acute leukemias (t-AL) with mixed lineage leukemia (MLL) gene rearrangement suggests that MLL translocations are causative events for t-AL. Using asymmetric multiplex PCR strategy followed by direct DNA sequencing, we characterized the genomic breakpoints of the MLL and AFF1 genes in two patients who developed t-AL with t(4;11)(q21;q23). Chemotherapeutic treatment of the primary disease in both patients included topoisomerase II (topo II) targeting agents. In one case, the MLL breakpoint was located in intron 9 at nucleotide position chr11:118354284 while the AFF1 breakpoint was in intron 3 at nucleotide position chr4:87992070. The breakpoint junction sequences revealed an insertion of two nucleotides at the MLL-AFF1 junction. In the other patient, the MLL breakpoint was located in intron 11 at nucleotide position chr11:118359130-32 and the AFF1 break was in intron 3 at nucleotide position chr4:87996215-17. The MLL breakpoint found in the latter patient was identical to that of two previously reported cases, strongly suggesting the presence of a preferential site of DNA cleavage in the presence of topo II inhibitor. In addition, microhomologies at the breakpoint junctions were indicative of DNA repair by the non-homologous end joining (NHEJ) pathway. This study further supports the evidence that MLL breakpoints in therapy-related acute leukemia with MLL-AFF1 are clustered in the telomeric half of the breakpoint cluster region that contains topo II recognition sites.
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Affiliation(s)
- Syed Khizer Hasan
- Department of Biomedicine and Prevention, University of Tor Vergata, Rome, Italy; Laboratorio di Neuro-Oncoematologia, Fondazione Santa Lucia, Rome, Italy
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18
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Sinha BK, Kumar A, Bhattacharjee S, Espey MG, Mason RP. Effect of nitric oxide on the anticancer activity of the topoisomerase-active drugs etoposide and adriamycin in human melanoma cells. J Pharmacol Exp Ther 2013; 347:607-14. [PMID: 24049059 PMCID: PMC3836306 DOI: 10.1124/jpet.113.207928] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2013] [Accepted: 09/18/2013] [Indexed: 11/22/2022] Open
Abstract
Nitric oxide (·NO) was originally identified as an innate cytotoxin. However, in tumors it can enhance resistance to chemotherapy and exacerbate cancer progression. Our previous studies indicated that (·NO/·NO-derived species react with etoposide (VP-16) in vitro and form products that show significantly reduced activity toward HL60 cells and lipopolysaccharide (LPS)-induced macrophages. Here, we further confirm the hypothesis that (÷)NO generation contributes to VP-16 resistance by examining interactions of ·NO with VP-16 in inducible nitric-oxide synthase (iNOS)-expressing human melanoma A375 cells. Inhibition of iNOS catalysis by N(6)-(1-iminoethyl)-L-lysine dihydrochloride (L-NIL) in human melanoma A375 cells reversed VP-16 resistance, leading to increased DNA damage and apoptosis. Furthermore, we found that coculturing A375 melanoma cells with LPS-induced macrophage RAW cells also significantly reduced VP-16 cytotoxicity and DNA damage in A375 cells. We also examined the interactions of (·)NO with another topoisomerase active drug, Adriamycin, in A375 cells. In contrast, to VP-16, (·)NO caused no significant modulation of cytotoxicity or Adriamycin-dependent apoptosis, suggesting that (⋅)NO does not interact with Adriamycin. Our studies support the hypothesis that (·)NO oxidative chemistry can detoxify VP-16 through direct nitrogen oxide radical attack. Our results provide insights into the pharmacology and anticancer mechanisms of VP-16 that may ultimately contribute to increased resistance, treatment failure, and induction of secondary leukemia in VP-16-treated patients.
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Affiliation(s)
- Birandra K Sinha
- Laboratory of Toxicology and Pharmacology, National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, North Carolina (B.K.S., A.K., S.B., R.P.M.); and National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland (M.G.E.)
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19
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Jacob DA, Gibson EG, Mercer SL, Deweese JE. Etoposide catechol is an oxidizable topoisomerase II poison. Chem Res Toxicol 2013; 26:1156-8. [PMID: 23863110 DOI: 10.1021/tx400205n] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Topoisomerase II regulates DNA topology by generating transient double-stranded breaks. The anticancer drug etoposide targets topoisomerase II and is associated with the formation of secondary leukemias in patients. The quinone and catechol metabolites of etoposide may contribute to strand breaks that trigger leukemic translocations. To further analyze the characteristics of etoposide metabolites, we extend our previous analysis of etoposide quinone to the catechol. We demonstrate that the catechol is ∼2-3-fold more potent than etoposide and under oxidative reaction conditions induces high levels of double-stranded DNA cleavage. These results support a role for etoposide catechol in contributing to therapy-induced DNA damage.
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Affiliation(s)
- David A Jacob
- Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy and Health Sciences, Nashville, Tennessee 37204-3951, USA
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20
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Rao VA. Iron chelators with topoisomerase-inhibitory activity and their anticancer applications. Antioxid Redox Signal 2013; 18:930-55. [PMID: 22900902 PMCID: PMC3557438 DOI: 10.1089/ars.2012.4877] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
SIGNIFICANCE Iron and topoisomerases are abundant and essential cellular components. Iron is required for several key processes such as DNA synthesis, mitochondrial electron transport, synthesis of heme, and as a co-factor for many redox enzymes. Topoisomerases serve as critical enzymes that resolve topological problems during DNA synthesis, transcription, and repair. Neoplastic cells have higher uptake and utilization of iron, as well as elevated levels of topoisomerase family members. Separately, the chelation of iron and the cytotoxic inhibition of topoisomerase have yielded potent anticancer agents. RECENT ADVANCES The chemotherapeutic drugs doxorubicin and dexrazoxane both chelate iron and target topoisomerase 2 alpha (top2α). Newer chelators such as di-2-pyridylketone-4,4,-dimethyl-3-thiosemicarbazone and thiosemicarbazone -24 have recently been identified as top2α inhibitors. The growing list of agents that appear to chelate iron and inhibit topoisomerases prompts the question of whether and how these two distinct mechanisms might interplay for a cytotoxic chemotherapeutic outcome. CRITICAL ISSUES While iron chelation and topoisomerase inhibition each represent mechanistically advantageous anticancer therapeutic strategies, dual targeting agents present an attractive multi-modal opportunity for enhanced anticancer tumor killing and overcoming drug resistance. The commonalities and caveats of dual inhibition are presented in this review. FUTURE DIRECTIONS Gaps in knowledge, relevant biomarkers, and strategies for future in vivo studies with dual inhibitors are discussed.
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Affiliation(s)
- V Ashutosh Rao
- Laboratory of Biochemistry, Division of Therapeutic Proteins, Office of Biotechnology Products, Office of Pharmaceutical Science, Center for Drug Evaluation and Research, Food and Drug Administration, Bethesda, Maryland 20892, USA.
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21
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Sinha BK, Bhattacharjee S, Chatterjee S, Jiang J, Motten AG, Kumar A, Espey MG, Mason RP. Role of nitric oxide in the chemistry and anticancer activity of etoposide (VP-16,213). Chem Res Toxicol 2013; 26:379-87. [PMID: 23402364 DOI: 10.1021/tx300480q] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Originally identified as an innate cytotoxin, nitric oxide ((·)NO) formation in tumors can influence chemotherapy and exacerbate cancer progression. Here, we examined the hypothesis that (·)NO generation contributes to cancer cell drug resistance toward the widely used anticancer drug Etoposide (VP-16). The UV-vis spectrum of VP-16 was not changed by exposure of VP-16 to (·)NO in aqueous buffer. In contrast, reddish-orange compound(s) characteristic of o-quinone- and nitroso-VP-16 were readily generated in a hydrophobic medium (chloroform) in an oxygen-dependent manner. Similar products were also formed when the VP-16 radical, generated from VP-16 and horseradish peroxidase/H2O2, was exposed directly to (·)NO in chloroform in the presence of oxygen. Separation and spectral analysis of VP-16 reaction extracts by electron spin resonance and UV-vis indicated the generation of the phenoxy radical and the o-quinone of VP-16, as well as putative nitroxide, iminoxyl, and other nitrogen oxide intermediates. Nitric oxide products of VP-16 displayed significantly diminished topoisomerase II-dependent cleavage of DNA and cytotoxicity to human HL-60 leukemia cells. LPS-mediated induction of nitric oxide synthase in murine macrophages resulted in VP-16 resistance compared to Raw cells. Furthermore, (·)NO products derived from iNOS rapidly reacted with VP-16 leading to decreased DNA damage and cytotoxicity. Together, these observations suggest that the formation of (·)NO in tumors (associated macrophages) can contribute to VP-16 resistance via the detoxification of VP-16.
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Affiliation(s)
- Birandra K Sinha
- Laboratory of Toxicology & Pharmacology, National Institutes of Environmental Health Sciences, Research Triangle Park, North Carolina 27709, United States
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22
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Secondary leukemia associated with the anti-cancer agent, etoposide, a topoisomerase II inhibitor. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2012; 9:2444-53. [PMID: 22851953 PMCID: PMC3407914 DOI: 10.3390/ijerph9072444] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 06/27/2012] [Accepted: 06/28/2012] [Indexed: 12/24/2022]
Abstract
Etoposide is an anticancer agent, which is successfully and extensively used in treatments for various types of cancers in children and adults. However, due to the increases in survival and overall cure rate of cancer patients, interest has arisen on the potential risk of this agent for therapy-related secondary leukemia. Topoisomerase II inhibitors, including etoposide and teniposide, frequently cause rearrangements involving the mixed lineage leukemia (MLL) gene on chromosome 11q23, which is associated with secondary leukemia. The prognosis is extremely poor for leukemias associated with rearrangements in the MLL gene, including etoposide-related secondary leukemias. It is of great importance to gain precise knowledge of the clinical aspects of these diseases and the mechanism underlying the leukemogenesis induced by this agent to ensure correct assessments of current and future therapy strategies. Here, I will review current knowledge regarding the clinical aspects of etoposide-related secondary leukemia, some probable mechanisms, and strategies for treating etoposide-induced leukemia.
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23
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Grimwade D, Mrózek K. Diagnostic and prognostic value of cytogenetics in acute myeloid leukemia. Hematol Oncol Clin North Am 2012; 25:1135-61, vii. [PMID: 22093581 DOI: 10.1016/j.hoc.2011.09.018] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The last 4 decades have seen major advances in understanding the genetic basis of acute myeloid leukemia (AML), and substantial improvements in survival of children and young adults with the disease. A key step forward was the discovery that AML cells harbor recurring cytogenetic abnormalities. The identification of the genes involved in chromosomal rearrangements has provided insights into the regulation of normal hematopoiesis and how disruption of key transcription factors and epigenetic modulators promote leukemic transformation. Cytogenetics has been widely adopted to provide the framework for development of risk-stratified treatment approaches to patient management.
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Affiliation(s)
- David Grimwade
- Cancer Genetics Laboratory, Department of Medical & Molecular Genetics, Guy's Hospital, King's College London School of Medicine, 8th Floor, Guy's Tower, London SE1 9RT, UK.
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24
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[Molecular determinants of response to topoisomerase II inhibitors]. Bull Cancer 2012; 98:1299-310. [PMID: 22023806 DOI: 10.1684/bdc.2011.1475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Human nuclear topoisomerases II (Top2) are involved in the relaxation of DNA supercoiling during transcription and replication but also play a pivotal role in the segregation of newly replicated chromosomes and in chromatin remodelling. Top2 have been used as targets for the development of anticancer drugs. These inhibitors include anthracyclines (doxorubcin, daunorubicin, epirubicin) and epipodophyllotoxins (etoposide), which are widely used in the clinic. These drugs poison Top2 by trapping the enzyme on its DNA cleavage sites, which results in irreversible double-strand breaks that are responsible for cell death. They also include Top2 catalytic inhibitors such as bisdioxopiperazines (ICRF-187 and merbarone), which inhibit Top2 binding to its substrate. Efficacy of Top2 inhibitors is still limited by the problem of resistance, which involves various mechanisms from drug transport and/or metabolism to the signalling and/or repair of Top2-mediated DNA lesions. Secondary malignancies induced by the poisoning of Top2β are also a major clinical issue. A better understanding of these mechanisms is critical for the future development of new Top2 inhibitors and the identification of biomarkers that could be used to predict tumour response to these drugs in the clinic and to adapt the treatment to each patient.
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25
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Molecular pathogenesis of secondary acute promyelocytic leukemia. Mediterr J Hematol Infect Dis 2011; 3:e2011045. [PMID: 22110895 PMCID: PMC3219647 DOI: 10.4084/mjhid.2011.045] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Accepted: 09/20/2011] [Indexed: 12/23/2022] Open
Abstract
Balanced chromosomal translocations that generate chimeric oncoproteins are considered to be initiating lesions in the pathogenesis of acute myeloid leukemia. The most frequent is the t(15;17)(q22;q21), which fuses the PML and RARA genes, giving rise to acute promyelocytic leukemia (APL). An increasing proportion of APL cases are therapy-related (t-APL), which develop following exposure to radiotherapy and/or chemotherapeutic agents that target DNA topoisomerase II (topoII), particularly mitoxantrone and epirubicin. To gain insights into molecular mechanisms underlying the formation of the t(15;17) we mapped the translocation breakpoints in a series of t-APLs, which revealed significant clustering according to the nature of the drug exposure. Remarkably, in approximately half of t-APL cases arising following mitoxantrone treatment for breast cancer or multiple sclerosis, the chromosome 15 breakpoint fell within an 8-bp “hotspot” region in PML intron 6, which was confirmed to be a preferential site of topoII-mediated DNA cleavage induced by mitoxantrone. Chromosome 15 breakpoints falling outside the “hotspot”, and the corresponding RARA breakpoints were also shown to be functional topoII cleavage sites. The observation that particular regions of the PML and RARA loci are susceptible to topoII-mediated DNA damage induced by epirubicin and mitoxantrone may underlie the propensity of these agents to cause APL.
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26
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Jacob DA, Mercer SL, Osheroff N, Deweese JE. Etoposide quinone is a redox-dependent topoisomerase II poison. Biochemistry 2011; 50:5660-7. [PMID: 21595477 DOI: 10.1021/bi200438m] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Etoposide is a topoisomerase II poison that is used to treat a variety of human cancers. Unfortunately, 2-3% of patients treated with etoposide develop treatment-related leukemias characterized by 11q23 chromosomal rearrangements. The molecular basis for etoposide-induced leukemogenesis is not understood but is associated with enzyme-mediated DNA cleavage. Etoposide is metabolized by CYP3A4 to etoposide catechol, which can be further oxidized to etoposide quinone. A CYP3A4 variant is associated with a lower risk of etoposide-related leukemias, suggesting that etoposide metabolites may be involved in leukemogenesis. Although etoposide acts at the enzyme-DNA interface, several quinones poison topoisomerase II via redox-dependent protein adduction. The effects of etoposide quinone on topoisomerase IIα-mediated DNA cleavage have been examined previously. Although findings suggest that the activity of the quinone is slightly greater than that of etoposide, these studies were carried out in the presence of significant levels of reducing agents (which should reduce etoposide quinone to the catechol). Therefore, we examined the ability of etoposide quinone to poison human topoisomerase IIα in the absence of reducing agents. Under these conditions, etoposide quinone was ∼5-fold more active than etoposide at inducing enzyme-mediated DNA cleavage. Consistent with other redox-dependent poisons, etoposide quinone inactivated topoisomerase IIα when incubated with the protein prior to DNA and lost activity in the presence of dithiothreitol. Unlike etoposide, the quinone metabolite did not require ATP for maximal activity and induced a high ratio of double-stranded DNA breaks. Our results support the hypothesis that etoposide quinone contributes to etoposide-related leukemogenesis.
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Affiliation(s)
- David A Jacob
- Department of Pharmaceutical Sciences, Lipscomb University College of Pharmacy, Nashville, Tennessee 37204-3951, USA
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27
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Leucémies aiguës myéloïdes secondaires aux traitements : implication des mécanismes de réparation de l'ADN. Bull Cancer 2011; 98:247-55. [DOI: 10.1684/bdc.2011.1325] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Vlasova II, Feng WH, Goff JP, Giorgianni A, Do D, Gollin SM, Lewis DW, Kagan VE, Yalowich JC. Myeloperoxidase-dependent oxidation of etoposide in human myeloid progenitor CD34+ cells. Mol Pharmacol 2011; 79:479-87. [PMID: 21097707 PMCID: PMC3061368 DOI: 10.1124/mol.110.068718] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2010] [Accepted: 11/19/2010] [Indexed: 11/22/2022] Open
Abstract
Etoposide is a widely used anticancer drug successfully used for the treatment of many types of cancer in children and adults. Its use, however, is associated with an increased risk of development of secondary acute myelogenous leukemia involving the mixed-lineage leukemia (MLL) gene (11q23) translocations. Previous studies demonstrated that the phenoxyl radical of etoposide can be produced by action of myeloperoxidase (MPO), an enzyme found in developing myeloid progenitor cells, the likely origin for myeloid leukemias. We hypothesized, therefore, that one-electron oxidation of etoposide by MPO to its phenoxyl radical is important for converting this anticancer drug to genotoxic and carcinogenic species in human CD34(+) myeloid progenitor cells. In the present study, using electron paramagnetic resonance spectroscopy, we provide conclusive evidence for MPO-dependent formation of etoposide phenoxyl radicals in growth factor-mobilized CD34(+) cells isolated from human umbilical cord blood and demonstrate that MPO-induced oxidation of etoposide is amplified in the presence of phenol. Formation of etoposide radicals resulted in the oxidation of endogenous thiols, thus providing evidence for etoposide-mediated MPO-catalyzed redox cycling that may play a role in enhanced etoposide genotoxicity. In separate studies, etoposide-induced DNA damage and MLL gene rearrangements were demonstrated to be dependent in part on MPO activity in CD34(+) cells. Together, our results are consistent with the idea that MPO-dependent oxidation of etoposide in human hematopoietic CD34(+) cells makes these cells especially prone to the induction of etoposide-related acute myeloid leukemia.
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Affiliation(s)
- Irina I. Vlasova
- Department of Pharmacology and Chemical Biology (J.C.Y., A.G., D.D.) and Department of Radiation Oncology (J.P.G.), University of Pittsburgh School of Medicine and Cancer Institute, Pittsburgh, Pennsylvania; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health (I.I.V., W.-H.F., V.E.K.) and Department of Human Genetics (S.M.G., D.W.L.), University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and Research Institute of Physico-Chemical Medicine (I.I.V.), Moscow, Russia
| | - Wei-Hong Feng
- Department of Pharmacology and Chemical Biology (J.C.Y., A.G., D.D.) and Department of Radiation Oncology (J.P.G.), University of Pittsburgh School of Medicine and Cancer Institute, Pittsburgh, Pennsylvania; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health (I.I.V., W.-H.F., V.E.K.) and Department of Human Genetics (S.M.G., D.W.L.), University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and Research Institute of Physico-Chemical Medicine (I.I.V.), Moscow, Russia
| | - Julie P. Goff
- Department of Pharmacology and Chemical Biology (J.C.Y., A.G., D.D.) and Department of Radiation Oncology (J.P.G.), University of Pittsburgh School of Medicine and Cancer Institute, Pittsburgh, Pennsylvania; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health (I.I.V., W.-H.F., V.E.K.) and Department of Human Genetics (S.M.G., D.W.L.), University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and Research Institute of Physico-Chemical Medicine (I.I.V.), Moscow, Russia
| | - Angela Giorgianni
- Department of Pharmacology and Chemical Biology (J.C.Y., A.G., D.D.) and Department of Radiation Oncology (J.P.G.), University of Pittsburgh School of Medicine and Cancer Institute, Pittsburgh, Pennsylvania; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health (I.I.V., W.-H.F., V.E.K.) and Department of Human Genetics (S.M.G., D.W.L.), University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and Research Institute of Physico-Chemical Medicine (I.I.V.), Moscow, Russia
| | - Duc Do
- Department of Pharmacology and Chemical Biology (J.C.Y., A.G., D.D.) and Department of Radiation Oncology (J.P.G.), University of Pittsburgh School of Medicine and Cancer Institute, Pittsburgh, Pennsylvania; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health (I.I.V., W.-H.F., V.E.K.) and Department of Human Genetics (S.M.G., D.W.L.), University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and Research Institute of Physico-Chemical Medicine (I.I.V.), Moscow, Russia
| | - Susanne M. Gollin
- Department of Pharmacology and Chemical Biology (J.C.Y., A.G., D.D.) and Department of Radiation Oncology (J.P.G.), University of Pittsburgh School of Medicine and Cancer Institute, Pittsburgh, Pennsylvania; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health (I.I.V., W.-H.F., V.E.K.) and Department of Human Genetics (S.M.G., D.W.L.), University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and Research Institute of Physico-Chemical Medicine (I.I.V.), Moscow, Russia
| | - Dale W. Lewis
- Department of Pharmacology and Chemical Biology (J.C.Y., A.G., D.D.) and Department of Radiation Oncology (J.P.G.), University of Pittsburgh School of Medicine and Cancer Institute, Pittsburgh, Pennsylvania; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health (I.I.V., W.-H.F., V.E.K.) and Department of Human Genetics (S.M.G., D.W.L.), University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and Research Institute of Physico-Chemical Medicine (I.I.V.), Moscow, Russia
| | - Valerian E. Kagan
- Department of Pharmacology and Chemical Biology (J.C.Y., A.G., D.D.) and Department of Radiation Oncology (J.P.G.), University of Pittsburgh School of Medicine and Cancer Institute, Pittsburgh, Pennsylvania; Department of Environmental and Occupational Health, Center for Free Radical and Antioxidant Health (I.I.V., W.-H.F., V.E.K.) and Department of Human Genetics (S.M.G., D.W.L.), University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and Research Institute of Physico-Chemical Medicine (I.I.V.), Moscow, Russia
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Pommier Y, Leo E, Zhang H, Marchand C. DNA topoisomerases and their poisoning by anticancer and antibacterial drugs. ACTA ACUST UNITED AC 2010; 17:421-33. [PMID: 20534341 DOI: 10.1016/j.chembiol.2010.04.012] [Citation(s) in RCA: 1343] [Impact Index Per Article: 89.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 04/28/2010] [Accepted: 04/29/2010] [Indexed: 02/07/2023]
Abstract
DNA topoisomerases are the targets of important anticancer and antibacterial drugs. Camptothecins and novel noncamptothecins in clinical development (indenoisoquinolines and ARC-111) target eukaryotic type IB topoisomerases (Top1), whereas human type IIA topoisomerases (Top2alpha and Top2beta) are the targets of the widely used anticancer agents etoposide, anthracyclines (doxorubicin, daunorubicin), and mitoxantrone. Bacterial type II topoisomerases (gyrase and Topo IV) are the targets of quinolones and aminocoumarin antibiotics. This review focuses on the molecular and biochemical characteristics of topoisomerases and their inhibitors. We also discuss the common mechanism of action of topoisomerase poisons by interfacial inhibition and trapping of topoisomerase cleavage complexes.
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Affiliation(s)
- Yves Pommier
- Laboratory of Molecular Pharmacology, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4255, USA.
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30
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Abstract
Therapy-related leukaemias are becoming an increasing healthcare problem as more patients survive their primary cancers. The nature of the causative agent has an important bearing upon the characteristics, biology, time to onset and prognosis of the resultant leukaemia. Agents targeting topoisomerase II induce acute leukaemias with balanced translocations that generally arise within 3 years, often involving the MLL, RUNX1 and RARA loci at 11q23, 21q22 and 17q21 respectively. Chromosomal breakpoints have been found to be preferential sites of topoisomerase II cleavage, which are believed to be repaired by the nonhomologous end-joining DNA repair pathway to generate chimaeric oncoproteins that underlie the resultant leukaemias. Therapy-related acute myeloid leukaemias occurring after exposure to antimetabolites and/or alkylating agents are biologically distinct with a longer latency period, being characterised by more complex karyotypes and loss of p53. Although treatment of therapy-related leukaemias represents a considerable challenge due to prior therapy and comorbidities, curative therapy is possible, particularly in those with favourable karyotypic features.
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Affiliation(s)
- Melanie Joannides
- Department of Medical & Molecular Genetics, King's College London School of Medicine, Guy's Hospital, London, UK
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Mondrala S, Eastmond DA. Topoisomerase II inhibition by the bioactivated benzene metabolite hydroquinone involves multiple mechanisms. Chem Biol Interact 2010; 184:259-68. [DOI: 10.1016/j.cbi.2009.12.023] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2009] [Revised: 12/07/2009] [Accepted: 12/15/2009] [Indexed: 11/26/2022]
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Chakravarti D, Zahid M, Backora M, Myers EM, Gaikwad N, Weisenburger DD, Cavalieri EL, Rogan EG, Joshi SS. Ortho-quinones of benzene and estrogens induce hyperproliferation of human peripheral blood mononuclear cells. Leuk Lymphoma 2009; 47:2635-44. [PMID: 17169809 DOI: 10.1080/10428190600931937] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Benzene is a known leukemogen. It has been hypothesized that benzene and natural estrogens initiate cancer by forming ortho-quinones (catechol quinones) that react with DNA in cells. These quinones form depurinating DNA adducts that generate the mutations leading to cancer. This study examined whether the treatment of normal human peripheral blood mononuclear cells with the ortho-quinones of benzene or estradiol would form DNA adducts and elicit an alteration in the proliferation of these cells. Both estradiol-3,4-quinone and benzene ortho-quinone formed depurinating DNA adducts and significantly increased the mitogen-induced proliferation of normal blood mononuclear cells. Immunophenotyping of the estradiol-3,4-quinone-treated blood cells indicated that monocyte/macrophage, natural killer and T-cells were particularly prone to hyperproliferation. Thus, DNA damage induced by the ortho-quinones of benzene and estradiol may promote the growth of human blood mononuclear cells, including those that appear in large numbers in leukemia and lymphoma.
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Affiliation(s)
- Dhrubajyoti Chakravarti
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, Omaha, NE 68198, USA
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Ottone T, Hasan SK, Montefusco E, Curzi P, Mays AN, Chessa L, Ferrari A, Conte E, Noguera NI, Lavorgna S, Ammatuna E, Divona M, Bovetti K, Amadori S, Grimwade D, Lo-Coco F. Identification of a potential “hotspot” DNA region in theRUNX1gene targeted by mitoxantrone in therapy-related acute myeloid leukemia with t(16;21) translocation. Genes Chromosomes Cancer 2009; 48:213-21. [DOI: 10.1002/gcc.20633] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Brassesco MS, Montaldi AP, Sakamoto-Hojo ET. Preferential induction of MLL(Mixed Lineage Leukemia) rearrangements in human lymphocyte cultures treated with etoposide. Genet Mol Biol 2009; 32:144-50. [PMID: 21637660 PMCID: PMC3032972 DOI: 10.1590/s1415-47572009000100022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2008] [Accepted: 08/27/2008] [Indexed: 11/22/2022] Open
Abstract
Topoisomerase II inhibitors are effective chemotherapeutic agents in the treatment of cancer, in spite of being associated with the development of secondary leukemia. Our purpose was to determine the effects of etoposide on different genomic regions, aiming at discovering whether there are preferential sites which can be targeted by this drug in peripheral lymphocytes from healthy individuals. The in vitro treatment with low doses of etoposide (0.25, 0.5, and 1 μg/mL, in 1 hour-pulse or continuous-48 h treatment) induced a significant increase in chromosomal aberrations, detected by conventional staining and FISH with specific probes for chromosomes 8 and 11, compared with untreated controls (p < 0.05). Additionally, the frequencies of alterations at 11q23, detected by MLL specific probes, were significantly higher (p < 0.005) in treated cells than in controls. In contrast, an analysis of rearrangements involving the IGH gene did not disclose differences between treatments. The present results demonstrated the potential of etoposide to interact with preferential chromosome sites in human lymphocytes, even at concentrations below the mean plasma levels measured in cancer patients. This greater susceptibility to etoposide-induced cleavage may explain the more frequent involvement of MLL in treatment-related leukemia.
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Affiliation(s)
- María Sol Brassesco
- Departamento de Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP Brazil
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Molecular analysis of t(15;17) genomic breakpoints in secondary acute promyelocytic leukemia arising after treatment of multiple sclerosis. Blood 2008; 112:3383-90. [PMID: 18650449 DOI: 10.1182/blood-2007-10-115600] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Therapy-related acute promyelocytic leukemia (t-APL) with t(15;17) translocation is a well-recognized complication of cancer treatment with agents targeting topoisomerase II. However, cases are emerging after mitoxantrone therapy for multiple sclerosis (MS). Analysis of 12 cases of mitoxantrone-related t-APL in MS patients revealed an altered distribution of chromosome 15 breakpoints versus de novo APL, biased toward disruption within PML intron 6 (11 of 12, 92% vs 622 of 1022, 61%: P = .035). Despite this intron spanning approximately 1 kb, breakpoints in 5 mitoxantrone-treated patients fell within an 8-bp region (1482-9) corresponding to the "hotspot" previously reported in t-APL, complicating mitoxantrone-containing breast cancer therapy. Another shared breakpoint was identified within the approximately 17-kb RARA intron 2 involving 2 t-APL cases arising after mitoxantrone treatment for MS and breast cancer, respectively. Analysis of PML and RARA genomic breakpoints in functional assays in 4 cases, including the shared RARA intron 2 breakpoint at 14 446-49, confirmed each to be preferential sites of topoisomerase IIalpha-mediated DNA cleavage in the presence of mitoxantrone. This study further supports the presence of preferential sites of DNA damage induced by mitoxantrone in PML and RARA genes that may underlie the propensity to develop this subtype of leukemia after exposure to this agent.
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Guillem V, Tormo M. Influence of DNA damage and repair upon the risk of treatment related leukemia. Leuk Lymphoma 2008; 49:204-17. [PMID: 18231906 DOI: 10.1080/10428190701769657] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Therapy-related myelodysplasia and acute myeloid leukemia (t-MDS/AML) are malignancies occurring after exposure to chemotherapy and/or radiotherapy. Several studies have addressed cumulative dose, dose intensity and exposure to specific agents of preceding cytotoxic therapy in relation to the risk of developing such leukemia. Since only a small percentage of patients exposed to cytotoxic therapy develop t-MDS/AML, it has been suggested that some genetic predisposition may be involved, specifically associated to polymorphisms in certain genes involved in chemotherapy/radiotherapy response - fundamentally genes intervening in drug detoxification and DNA synthesis and repair. A review is made of the genetic studies related to t-MDS/AML predisposition, focusing on the mechanistic findings of how specific chemotherapeutic drug exposure produces DNA damage and induces the chromosomal abnormalities characteristic of t-MDS/AML, the molecular pathways involved in repairing such drug induced damage, and the way in which they influence t-MDS/AML genesis. Specific issues are (a) the interaction of topoisomerase II inhibitors, alkylators and antimetabolite drugs with DNA repair mechanisms and their impact on t-MDS/AML leukemogenicity and (b) the influence of DNA polymorphisms in genes involved in DNA repair, drug metabolization and nucleotide synthesis, paying special attention to the relevance of folate metabolism. Finally, we discuss some aspects relating to study design that are most suitable for characterizing associations between drug exposure and genotypes related to t-MDS/AML risk - stressing the importance of the inclusion of chemotherapy-exposed control groups.
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Affiliation(s)
- Vicent Guillem
- Servicio de Hematología y Oncología, Hospital Clínico Universitario de Valencia, Universidad de Valencia, Valencia, Spain
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Prospective tracing of MLL-FRYL clone with low MEIS1 expression from emergence during neuroblastoma treatment to diagnosis of myelodysplastic syndrome. Blood 2008; 111:3802-12. [PMID: 18195096 DOI: 10.1182/blood-2007-07-096065] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
We prospectively observed a child exposed to intensive multimodality therapy for metastatic neuroblastoma from emergence of a MLL translocation to disease diagnosis. The t(4;11)(p12;q23) was detected in the marrow 17 months after starting treatment following topoisomerase II poisons, alkylating agents, local radiation, hematopoietic stem cell transplantation, anti-GD2 monoclonal antibody with granulocyte macrophage-colony-stimulating factor, and a high cumulative dose of oral etoposide. Reciprocal genomic breakpoint junctions and fusion transcripts joined MLL with FRYL, the Drosophila melanogaster protein homologue of which regulates cell fate. Etoposide metabolites induced topoisomerase II cleavage complexes that could form both breakpoint junctions. Cells harboring the translocation replaced the marrow without clinical evidence of leukemia and differentiation appeared unaffected for 37 months. Subsequent bilineage dysplasia and increased blasts in addition to the translocation fulfilled criteria for MDS. The MEIS1 target gene of typical MLL fusion oncoproteins was underexpressed before and at MDS diagnosis. These results are consistent with repair of topoisomerase II cleavage from etoposide metabolites as the translocation mechanism, whereas other agents in the regimen may have contributed to progression of the clone with the translocation to MDS. MLL-FRYL did not increase MEIS1 expression, conferred a proliferative advantage without altering differentiation, and had protracted latency to disease.
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Kapiszewska M, Cierniak A, Elas M, Lankoff A. Lifespan of etoposide-treated human neutrophils is affected by antioxidant ability of quercetin. Toxicol In Vitro 2007; 21:1020-30. [PMID: 17467952 DOI: 10.1016/j.tiv.2007.03.005] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2006] [Revised: 03/06/2007] [Accepted: 03/12/2007] [Indexed: 11/29/2022]
Abstract
Neutropenia is the primary dose-limiting effect of etoposide toxicity resulting in a decreased efficiency of cancer treatment. Hence, the protection of neutrophils has important clinical implications. We investigated whether quercetin, due to its antioxidant properties, is able to modulate the damaging activity of etoposide. DNA damage, evaluated by the comet assay, and apoptosis, determined by FACScan flow cytometry using Annexin/PI, increased with etoposide doses. The intracellular level of reactive oxygen species (ROS) was enhanced in resting neutrophils incubated with etoposide at concentrations up to 25 microM; above this concentration etoposide revealed antioxidant properties. Only in latex-activated neutrophils, i.e. with latex-stimulated respiratory burst was the ROS production inhibited, as assessed by the luminol amplified chemiluminescence. The characteristic electron spin resonance (ESR) signal of etoposide phenoxyl radical, which occurs in the presence of myeloperoxidase, H2O2 and etoposide, was quenched by quercetin in a dose-dependent manner (0.1-0.5 microM). Quercetin also inhibited DNA damage induced by etoposide and enhanced the inhibitory action of etoposide on the ROS formation in neutrophils. However, quercetin (1 microM) lowered early and late apoptosis/necrosis only when apoptosis was induced by 25 microM etoposide; at higher etoposide concentration apoptosis was enhanced. Summing up, antioxidant adjuvant therapy using quercetin can be beneficial in prolonging neutrophils' lifespan in peripheral blood only when etoposide plasma concentration is low.
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Affiliation(s)
- Maria Kapiszewska
- Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Gronostajowa 7, 30-387 Krakow, Poland.
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McClendon AK, Osheroff N. DNA topoisomerase II, genotoxicity, and cancer. Mutat Res 2007; 623:83-97. [PMID: 17681352 PMCID: PMC2679583 DOI: 10.1016/j.mrfmmm.2007.06.009] [Citation(s) in RCA: 300] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2006] [Revised: 06/06/2007] [Accepted: 06/16/2007] [Indexed: 12/23/2022]
Abstract
Type II topoisomerases are ubiquitous enzymes that play essential roles in a number of fundamental DNA processes. They regulate DNA under- and overwinding, and resolve knots and tangles in the genetic material by passing an intact double helix through a transient double-stranded break that they generate in a separate segment of DNA. Because type II topoisomerases generate DNA strand breaks as a requisite intermediate in their catalytic cycle, they have the potential to fragment the genome every time they function. Thus, while these enzymes are essential to the survival of proliferating cells, they also have significant genotoxic effects. This latter aspect of type II topoisomerase has been exploited for the development of several classes of anticancer drugs that are widely employed for the clinical treatment of human malignancies. However, considerable evidence indicates that these enzymes also trigger specific leukemic chromosomal translocations. In light of the impact, both positive and negative, of type II topoisomerases on human cells, it is important to understand how these enzymes function and how their actions can destabilize the genome. This article discusses both aspects of human type II topoisomerases.
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Affiliation(s)
- A. Kathleen McClendon
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA
| | - Neil Osheroff
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA
- Department of Medicine (Hematology/Oncology), Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146, USA
- Corresponding author. Tel: +1 615 3224338; fax: +1 615 3431166, E-mail address: (N. Osheroff)
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42
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Azarova AM, Lyu YL, Lin CP, Tsai YC, Lau JYN, Wang JC, Liu LF. Roles of DNA topoisomerase II isozymes in chemotherapy and secondary malignancies. Proc Natl Acad Sci U S A 2007; 104:11014-9. [PMID: 17578914 PMCID: PMC1904155 DOI: 10.1073/pnas.0704002104] [Citation(s) in RCA: 227] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Drugs that target DNA topoisomerase II (Top2), including etoposide (VP-16), doxorubicin, and mitoxantrone, are among the most effective anticancer drugs in clinical use. However, Top2-based chemotherapy has been associated with higher incidences of secondary malignancies, notably the development of acute myeloid leukemia in VP-16-treated patients. This association is suggestive of a link between carcinogenesis and Top2-mediated DNA damage. We show here that VP-16-induced carcinogenesis involves mainly the beta rather than the alpha isozyme of Top2. In a mouse skin carcinogenesis model, the incidence of VP-16-induced melanomas in the skin of 7,12-dimethylbenz[a]anthracene-treated mice is found to be significantly higher in TOP2beta(+) than in skin-specific top2beta-knockout mice. Furthermore, VP-16-induced DNA sequence rearrangements and double-strand breaks (DSBs) are found to be Top2beta-dependent and preventable by cotreatment with a proteasome inhibitor, suggesting the importance of proteasomal degradation of the Top2beta-DNA cleavage complexes in VP-16-induced DNA sequence rearrangements. VP-16 cytotoxicity in transformed cells expressing both Top2 isozymes is, however, found to be primarily Top2alpha-dependent. These results point to the importance of developing Top2alpha-specific anticancer drugs for effective chemotherapy without the development of treatment-related secondary malignancies.
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Affiliation(s)
- Anna M. Azarova
- *Department of Pharmacology, University of Medicine and Dentistry of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854
| | - Yi Lisa Lyu
- *Department of Pharmacology, University of Medicine and Dentistry of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854
| | - Chao-Po Lin
- *Department of Pharmacology, University of Medicine and Dentistry of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854
| | - Yuan-Chin Tsai
- *Department of Pharmacology, University of Medicine and Dentistry of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854
| | - Johnson Yiu-Nam Lau
- Avagenex Pharmaceuticals, 6 Dey Farm Drive, Princeton Junction, NJ 08550; and
| | - James C. Wang
- Department of Molecular and Cellular Biology, Harvard University, 7 Divinity Avenue, Cambridge, MA 02138
- To whom correspondence may be addressed. E-mail: or
| | - Leroy F. Liu
- *Department of Pharmacology, University of Medicine and Dentistry of New Jersey, 675 Hoes Lane, Piscataway, NJ 08854
- To whom correspondence may be addressed. E-mail: or
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Abstract
Acute leukemias with balanced chromosomal translocations, protean morphologic and immunophenotypic presentations but generally shorter latency and absence of myelodysplasia are recognized as a complication of anti-cancer drugs that behave as topoisomerase II poisons. Translocations affecting the breakpoint cluster region of the MLL gene at chromosome band 11q23 are the most common molecular genetic aberrations in leukemias associated with the topoisomerase II poisons. These agents perturb the cleavage-religation equilibrium of topoisomerase II and increase cleavage complexes. One model suggests that this damages the DNA directly and leads to chromosomal breakage, which may result in untoward DNA recombination in the form of translocations. This review will summarize the evidence for topoisomerase II involvement in the genesis of translocations and extension of the model to acute leukemia in infants characterized by similar MLL translocations.
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Affiliation(s)
- Carolyn A Felix
- Division of Oncology, Children's Hospital of Philadelphia, Philadelphia, PA 19104, USA.
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Sung PA, Libura J, Richardson C. Etoposide and illegitimate DNA double-strand break repair in the generation of MLL translocations: new insights and new questions. DNA Repair (Amst) 2006; 5:1109-18. [PMID: 16809075 DOI: 10.1016/j.dnarep.2006.05.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Faithful repair of chromosomal double-strand breaks (DSBs) is central to genome integrity and the suppression of genome rearrangements including translocations that are a hallmark of leukemia, lymphoma, and soft-tissue sarcomas [B. Elliott, M. Jasin, Double-strand breaks and translocations in cancer, Cell. Mol. Life Sci. 59 (2002) 373-385; D.C. van Gent, J.H. Hoeijmakers, R. Kanaar, Chromosomal stability and the DNA double-stranded break connection, Nat. Rev. Genet. 2 (2001) 196-206]. Chemotherapy agents that target the essential cellular enzyme topoisomerase II (topo II) are known promoters of DSBs and are associated with therapy-related leukemias. There is a clear clinical association between previous exposure to etoposide and therapy-related acute myeloid leukemia (t-AML) characterized by chromosomal rearrangements involving the mixed lineage leukemia (MLL) gene on chromosome band 11q23 [C.A. Felix, Leukemias related to treatment with DNA topoisomerase II inhibitors, Med. Pediatr. Oncol. 36 (2001) 525-535]. Most MLL rearrangements initiate within a well-characterized 8.3 kb region that contains both putative topo II cleavage recognition sequences and repetitive elements leading to the logical hypothesis that MLL is particularly susceptible to aberrant cleavage and homology-mediated fusion to repetitive elements located on novel chromosome partners. In this review, we will discuss the findings and implications of recent attempts to confirm this hypothesis.
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Affiliation(s)
- P A Sung
- Institute for Cancer Genetics, Department of Pathology, Columbia University, New York, NY 10032, USA
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45
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Duca M, Guianvarc'h D, Oussedik K, Halby L, Garbesi A, Dauzonne D, Monneret C, Osheroff N, Giovannangeli C, Arimondo PB. Molecular basis of the targeting of topoisomerase II-mediated DNA cleavage by VP16 derivatives conjugated to triplex-forming oligonucleotides. Nucleic Acids Res 2006; 34:1900-11. [PMID: 16598074 PMCID: PMC1447649 DOI: 10.1093/nar/gkl126] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Human topoisomerase II (topo II) is the cellular target for a number of widely used antitumor agents, such as etoposide (VP16). These agents 'poison' the enzyme and induce it to generate DNA breaks that are lethal to the cell. Topo II-targeted drugs show a limited sequence preference, triggering double-stranded breaks throughout the genome. Circumstantial evidence strongly suggests that some of these breaks induce chromosomal translocations that lead to specific types of leukaemia (called treatment-related or secondary leukaemia). Therefore, efforts are ongoing to decrease these secondary effects. An interesting option is to increase the sequence-specificity of topo II-targeted drugs by attaching them to triplex-forming oligonucleotides (TFO) that bind to DNA in a highly sequence-specific manner. Here five derivatives of VP16 were attached to TFOs. The active topo II poisons, once linked, induced cleavage 13-14 bp from the triplex end where the drug was attached. The use of triple-helical DNA structures offers an efficient strategy for targeting topo II-mediated cleavage to DNA specific sequences. Finally, drug-TFO conjugates are useful tools to investigate the mechanistic details of topo II poisoning.
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Affiliation(s)
- Maria Duca
- UMR 5153 CNRSParis, France
- Muséum National d'Histoire Naturelle USM0503Paris, France
- INSERM UR565Paris, France
- 43 rue Cuvier75231 Paris cedex 05, France
| | - Dominique Guianvarc'h
- UMR 5153 CNRSParis, France
- Muséum National d'Histoire Naturelle USM0503Paris, France
- INSERM UR565Paris, France
- 43 rue Cuvier75231 Paris cedex 05, France
| | - Kahina Oussedik
- UMR 5153 CNRSParis, France
- Muséum National d'Histoire Naturelle USM0503Paris, France
- INSERM UR565Paris, France
- 43 rue Cuvier75231 Paris cedex 05, France
| | - Ludovic Halby
- UMR 5153 CNRSParis, France
- Muséum National d'Histoire Naturelle USM0503Paris, France
- INSERM UR565Paris, France
- 43 rue Cuvier75231 Paris cedex 05, France
| | - Anna Garbesi
- Istituto di Sintesi Organica e Fotoreattività del Consiglio Nazionale delle Ricerche (ISOF-CNR) Via Gobetti 10140129 Bologna, Italy
| | - Daniel Dauzonne
- UMR 176 CNRS, Institut Curie Section de Recherche26 rue d'Ulm 75248 Paris cedex 05, France
| | - Claude Monneret
- UMR 176 CNRS, Institut Curie Section de Recherche26 rue d'Ulm 75248 Paris cedex 05, France
| | - Neil Osheroff
- Department of Biochemistry, Vanderbilt University School of MedicineNashville TN 37232-0146, USA
- Department of Medicine (Hematology/Oncology), Vanderbilt University School of MedicineNashville TN 37232-0146, USA
| | - Carine Giovannangeli
- UMR 5153 CNRSParis, France
- Muséum National d'Histoire Naturelle USM0503Paris, France
- INSERM UR565Paris, France
- 43 rue Cuvier75231 Paris cedex 05, France
| | - Paola B. Arimondo
- UMR 5153 CNRSParis, France
- Muséum National d'Histoire Naturelle USM0503Paris, France
- INSERM UR565Paris, France
- 43 rue Cuvier75231 Paris cedex 05, France
- To whom correspondence should be addressed. Tel: +33 1 40793859; Fax: +33 1 40793705;
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Ng A, Taylor GM, Eden OB. Genotoxicity of etoposide: greater susceptibility of MLL than other target genes. ACTA ACUST UNITED AC 2006; 164:164-7. [PMID: 16434323 DOI: 10.1016/j.cancergencyto.2005.08.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2005] [Revised: 07/18/2005] [Accepted: 08/03/2005] [Indexed: 11/22/2022]
Abstract
The ability of topoisomerase 2 inhibitors to induce DNA breakage is well recognized. Previous studies, however, have concentrated on the effects on individual genes. The effects of etoposide on the MLL, RUNX1, and MLLT3 genes were simultaneously studied in the same hemopoietic cell population. We found MLL to be more susceptible to etoposide-induced cleavage than RUNX1 and MLLT3, with maximum cleavage at a lower drug concentration. A higher level of MLL than other gene cleavage was also detected after cellular exposure to all drug concentrations. Greater susceptibility to topoisomerase 2 inhibitor-induced cleavage may explain the more frequent involvement of MLL in treatment-related leukemogenesis.
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Affiliation(s)
- A Ng
- Immunogenetics Laboratory, University of Manchester, Oxford Road, Manchester, UK M13 3PL.
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48
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Abstract
Therapy-related cancers, defined as second primary cancers that arise as a consequence of chemotherapy and/or radiotherapy, are unusual in that they have a well-defined aetiology. Knowledge of the specific nature of the initiating exposure and exactly when it occurred has made it easier to identify crucial genetic events and to model these in vitro and in vivo. As such, the study of therapy-related cancers has led to the elucidation of discrete mechanisms of carcinogenesis, including DNA double-strand-break-induced gene translocation and genomic instability conferred by loss of DNA repair. Unsurprisingly, some of these mechanisms seem to operate in the development of sporadic cancers.
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Affiliation(s)
- James M Allan
- Epidemiology and Genetics Unit, Department of Biology, University of York, Heslington, York, YO10 5YW, UK.
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49
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Lemke K, Wojciechowski M, Laine W, Bailly C, Colson P, Baginski M, Larsen AK, Skladanowski A. Induction of unique structural changes in guanine-rich DNA regions by the triazoloacridone C-1305, a topoisomerase II inhibitor with antitumor activities. Nucleic Acids Res 2005; 33:6034-47. [PMID: 16254080 PMCID: PMC1270948 DOI: 10.1093/nar/gki904] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Revised: 09/29/2005] [Accepted: 09/29/2005] [Indexed: 11/12/2022] Open
Abstract
We recently reported that the antitumor triazoloacridone, compound C-1305, is a topoisomerase II poison with unusual properties. In this study we characterize the DNA interactions of C-1305 in vitro, in comparison with other topoisomerase II inhibitors. Our results show that C-1305 binds to DNA by intercalation and possesses higher affinity for GC- than AT-DNA as revealed by surface plasmon resonance studies. Chemical probing with DEPC indicated that C-1305 induces structural perturbations in DNA regions with three adjacent guanine residues. Importantly, this effect was highly specific for C-1305 since none of the other 22 DNA interacting drugs tested was able to induce similar structural changes in DNA. Compound C-1305 induced stronger structural changes in guanine triplets at higher pH which suggested that protonation/deprotonation of the drug is important for this drug-specific effect. Molecular modeling analysis predicts that the zwitterionic form of C-1305 intercalates within the guanine triplet, resulting in widening of both DNA grooves and aligning of the triazole ring with the N7 atoms of guanines. Our results show that C-1305 binds to DNA and induces very specific and unusual structural changes in guanine triplets which likely plays an important role in the cytotoxic and antitumor activity of this unique compound.
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Affiliation(s)
- Krzysztof Lemke
- Laboratory of Cellular and Molecular Pharmacology, Department of Pharmaceutical Technology and Biochemistry, Gdansk University of TechnologyGdansk, Poland
- Group of Biology and Pharmacogenetics of Human Tumors, INSERM U673, Université Pierre et Marie Curie (UPMC-Paris 6), Hôpital Saint-AntoineParis, 75571 Paris 12, France
| | - Marcin Wojciechowski
- Laboratory of Cellular and Molecular Pharmacology, Department of Pharmaceutical Technology and Biochemistry, Gdansk University of TechnologyGdansk, Poland
| | - William Laine
- INSERM U-524 et Laboratoire de Pharmacologie Antitumorale du Centre Oscar Lambret, IRCL59045 Lille Cedex, France
| | - Christian Bailly
- INSERM U-524 et Laboratoire de Pharmacologie Antitumorale du Centre Oscar Lambret, IRCL59045 Lille Cedex, France
| | - Pierre Colson
- Biospectroscopy and Physical Chemistry Unit, Department of Chemistry and Natural and Synthetic Drugs Research Center, University of LiègeSart-Tilman, 4000, Liège, Belgium
| | - Maciej Baginski
- Laboratory of Cellular and Molecular Pharmacology, Department of Pharmaceutical Technology and Biochemistry, Gdansk University of TechnologyGdansk, Poland
| | - Annette K. Larsen
- Group of Biology and Pharmacogenetics of Human Tumors, INSERM U673, Université Pierre et Marie Curie (UPMC-Paris 6), Hôpital Saint-AntoineParis, 75571 Paris 12, France
| | - Andrzej Skladanowski
- Laboratory of Cellular and Molecular Pharmacology, Department of Pharmaceutical Technology and Biochemistry, Gdansk University of TechnologyGdansk, Poland
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Cirz RT, Chin JK, Andes DR, de Crécy-Lagard V, Craig WA, Romesberg FE. Inhibition of mutation and combating the evolution of antibiotic resistance. PLoS Biol 2005; 3:e176. [PMID: 15869329 PMCID: PMC1088971 DOI: 10.1371/journal.pbio.0030176] [Citation(s) in RCA: 382] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2004] [Accepted: 03/15/2005] [Indexed: 11/28/2022] Open
Abstract
The emergence of drug-resistant bacteria poses a serious threat to human health. In the case of several antibiotics, including those of the quinolone and rifamycin classes, bacteria rapidly acquire resistance through mutation of chromosomal genes during therapy. In this work, we show that preventing induction of the SOS response by interfering with the activity of the protease LexA renders pathogenic Escherichia coli unable to evolve resistance in vivo to ciprofloxacin or rifampicin, important quinolone and rifamycin antibiotics. We show in vitro that LexA cleavage is induced during RecBC-mediated repair of ciprofloxacin-mediated DNA damage and that this results in the derepression of the SOS-regulated polymerases Pol II, Pol IV and Pol V, which collaborate to induce resistance-conferring mutations. Our findings indicate that the inhibition of mutation could serve as a novel therapeutic strategy to combat the evolution of antibiotic resistance.
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Affiliation(s)
- Ryan T Cirz
- 1Department of Chemistry, The Scripps Research InstituteLa Jolla, CaliforniaUnited States of America
| | - Jodie K Chin
- 1Department of Chemistry, The Scripps Research InstituteLa Jolla, CaliforniaUnited States of America
| | - David R Andes
- 2The Department of Medicine, Section of Infectious DiseaseUniversity of Wisconsin Medical School, Madison, WisconsinUnited States of America
| | - Valérie de Crécy-Lagard
- 3Molecular Biology, The Scripps Research InstituteLa Jolla, CaliforniaUnited States of America
| | - William A Craig
- 2The Department of Medicine, Section of Infectious DiseaseUniversity of Wisconsin Medical School, Madison, WisconsinUnited States of America
| | - Floyd E Romesberg
- 1Department of Chemistry, The Scripps Research InstituteLa Jolla, CaliforniaUnited States of America
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