151
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Ammatuna E, Montefusco E, Pacilli M, Divona M, Ardiri D, Centonze D, Lo-Coco F. Use of arsenic trioxide in secondary acute promyelocytic leukemia developing after treatment of multiple sclerosis with mitoxantrone. Leuk Lymphoma 2009; 50:1217-8. [DOI: 10.1080/10428190902912486] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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152
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Bowles DW, Flaig TW. Mitoxantrone-Associated Acute Myelogenous Leukemia in a Patient with High-Risk Adenocarcinoma of the Prostate: A Case Report and Brief Review. Cancer Invest 2009; 24:517-20. [PMID: 16939961 DOI: 10.1080/07357900600814953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
BACKGROUND Mitoxantrone, a topoisomerase II-targeted drug, is used to treat several conditions and is a Food and Drug Administration approved chemotherapeutic agent for the treatment of advanced carcinoma of the prostate. CASE REPORT A 64-year-old male with high-risk prostate cancer was treated with adjuvant mitoxantrone (12 mg/meter2) every 3 weeks for 6 cycles. Approximately 10 months after finishing therapy, he was diagnosed with an inv [16] Acute Myelogenous Leukemia (AML). Despite aggressive treatment and support, the patient had a rapidly fatal clinical course. CONCLUSION Despite its regular use in this setting, this is the first reported case of treatment-associated AML after mitoxantrone in prostate cancer.
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Affiliation(s)
- Daniel W Bowles
- Department of Medicine, University of Colorado School of Medicine, Denver, CO, USA
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153
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Abstract
Recent molecular studies have expanded the biological contexts in which topoisomerase II (TOP2) has crucial functions, including DNA replication, transcription and chromosome segregation. Although the biological functions of TOP2 are important for ensuring genomic integrity, the ability to interfere with TOP2 and generate enzyme-mediated DNA damage is an effective strategy for cancer chemotherapy. The molecular tools that have allowed an understanding of the biological functions of TOP2 are also being applied to understanding the details of drug action. These studies promise refined targeting of TOP2 as an effective anticancer strategy.
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Affiliation(s)
- John L Nitiss
- Molecular Pharmacology Department, St Jude Children's Research Hospital, Memphis, TN 38105, USA.
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154
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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: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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155
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Galleani J, Miranda C, Pierotti MA, Greco A. H2AX phosphorylation and kinetics of radiation-induced DNA double strand break repair in human primary thyrocytes. Thyroid 2009; 19:257-64. [PMID: 19265496 DOI: 10.1089/thy.2008.0195] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Papillary thyroid carcinoma (PTC) represents the most frequent thyroid neoplasia and is associated with radiation exposure. A consistent proportion of PTC is characterized by chromosome rearrangements producing RET and TRK oncogenes, but the mechanisms underlying the thyrocyte propensity to such alterations are poorly understood. Diminished capacity of thyrocytes to repair radiation-induced DNA double strand breaks (DSBs) might play a role in chromosome rearrangements; however, this question has not been fully addressed due to the lack of physiologically relevant experimental models. METHODS Several normal human thyroid primary cultures were produced and characterized for their capacity to repair the DNA DSBs induced by ionizing radiation. For comparison, normal human bronchial epithelial cells were used. We employed the gammaH2AX foci assay; counts were determined at different time points after irradiation. RESULTS All the thyrocyte samples analyzed showed similar DNA DSBs induction. The rate of gammaH2AX foci clearance was homogenous, showing only small differences among samples. CONCLUSION This work reports the first characterization of DNA DSB repair in human primary thyrocytes, a relevant clinical model for thyroid carcinogenesis, and represents an important step toward dissection of the link between DNA DSB repair and thyroid-specific oncogenic rearrangements.
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Affiliation(s)
- Jessica Galleani
- Department of Experimental Oncology, Operative Unit Molecular Mechanisms of Cancer Growth and Progression, Milan, Italy
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156
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Ellis R, Boggild M. Therapy-related acute leukaemia with Mitoxantrone: what is the risk and can we minimise it? Mult Scler 2009; 15:505-8. [PMID: 19251838 DOI: 10.1177/1352458508100967] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND Therapy-related acute leukaemia (TRAL) is a concern for neurologists and patients when considering treatment with Mitoxantrone for multiple sclerosis (MS). The timing of this complication, risk, mortality and relationship to exposure remain uncertain. METHODS We searched literature for publications relating to Mitoxantrone in MS, reviewed publication references and handsearched abstract lists to identify case-series reporting follow-up and complications of treatment with Mitoxantrone. We combined this with our local database of 250 cases treated since 1997. We also identified all reported individual cases of TRAL and extracted data reporting exposure (dose or mg/m(2)), timing and outcome of TRAL. RESULTS Case-series including 5472 patients were identified; mean dose of Mitoxantrone was 74.2 mg/m(2) (range:12-120 mg/m(2)). TRAL was diagnosed in 0.30% (1 in 333). In 34 TRAL cases, sufficient data was available to inform analysis of exposure. Onset was a median of 18.5 months following Mitoxantrone treatment (range:4-60). Acute Myelocytic Leukaemia and Acute Promyelocytic Leukaemia represented 46.4% each of the leukaemia subtypes. Six of 25 TRAL patients, where outcome was reported, died (24%). Over 80% of cases occurred in patients exposed to >60 mg/m(2), with a relative risk of 1.44 (CI95%:1.18-1.70) when comparing total dose >60 mg/m(2) against <60 mg/m(2) strongly suggesting a relationship between risk of TRAL and total dose.
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Affiliation(s)
- R Ellis
- Walton Centre for Neurology and Neurosurgery, Neurological Sciences, Liverpool, UK.
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157
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Therapy-related acute myeloid leukaemia with t(8;16)(p11;p13);MOZ-CBP and polymorphisms in detoxifying and DNA repair genes. Leukemia 2009; 23:1164-7. [PMID: 19158836 DOI: 10.1038/leu.2008.383] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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158
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Weinstein JL, Ayyanar K, Watral MA. Secondary neoplasms following treatment for brain tumors. Cancer Treat Res 2009; 150:239-273. [PMID: 19834673 DOI: 10.1007/b109924_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Affiliation(s)
- Joanna L Weinstein
- Division of Hematology, Oncology and Stem Cell Transplantation, Children's Memorial Hospital, Chicago, IL, USA.
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159
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Deweese JE, Osheroff N. The DNA cleavage reaction of topoisomerase II: wolf in sheep's clothing. Nucleic Acids Res 2008; 37:738-48. [PMID: 19042970 PMCID: PMC2647315 DOI: 10.1093/nar/gkn937] [Citation(s) in RCA: 334] [Impact Index Per Article: 20.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Topoisomerase II is an essential enzyme that is required for virtually every process that requires movement of DNA within the nucleus or the opening of the double helix. This enzyme helps to regulate DNA under- and overwinding and removes knots and tangles from the genetic material. In order to carry out its critical physiological functions, topoisomerase II generates transient double-stranded breaks in DNA. Consequently, while necessary for cell survival, the enzyme also has the capacity to fragment the genome. The DNA cleavage/ligation reaction of topoisomerase II is the target for some of the most successful anticancer drugs currently in clinical use. However, this same reaction also is believed to trigger chromosomal translocations that are associated with specific types of leukemia. This article will familiarize the reader with the DNA cleavage/ligation reaction of topoisomerase II and other aspects of its catalytic cycle. In addition, it will discuss the interaction of the enzyme with anticancer drugs and the mechanisms by which these agents increase levels of topoisomerase II-generated DNA strand breaks. Finally, it will describe dietary and environmental agents that enhance DNA cleavage mediated by the enzyme.
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Affiliation(s)
- Joseph E Deweese
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, TN 37232-0146 USA
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160
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Management of acute promyelocytic leukemia: recommendations from an expert panel on behalf of the European LeukemiaNet. Blood 2008; 113:1875-91. [PMID: 18812465 DOI: 10.1182/blood-2008-04-150250] [Citation(s) in RCA: 594] [Impact Index Per Article: 37.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The introduction of all-trans retinoic acid (ATRA) and, more recently, arsenic trioxide (ATO) into the therapy of acute promyelocytic leukemia (APL) has revolutionized the management and outcome of this disease. Several treatment strategies using these agents, usually in combination with chemotherapy, but also without or with minimal use of cytotoxic agents, have provided excellent therapeutic results. Cure of APL patients, however, is also dependent on peculiar aspects related to the management and supportive measures that are crucial to counteract life-threatening complications associated with the disease biology and molecularly targeted treatment. The European LeukemiaNet recently appointed an international panel of experts to develop evidence- and expert opinion-based guidelines on the diagnosis and management of APL. Together with providing current indications on genetic diagnosis, modern risk-adapted front-line therapy and salvage treatment, the review contains specific recommendations for the identification and management of most important complications such as the bleeding disorder, APL differentiation syndrome, QT prolongation and other ATRA- and ATO-related toxicities, as well as for molecular assessment of response to treatment. Finally, the approach to special situations is also discussed, including management of APL in children, elderly patients, and pregnant women.
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161
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Ko MW, Tamhankar MA, Volpe NJ, Porter D, McGrath C, Galetta SL. Acute promyelocytic leukemic involvement of the optic nerves following mitoxantrone treatment for multiple sclerosis. J Neurol Sci 2008; 273:144-7. [PMID: 18687447 DOI: 10.1016/j.jns.2008.06.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Revised: 06/19/2008] [Accepted: 06/24/2008] [Indexed: 11/24/2022]
Abstract
Mitoxantrone, the first immunosuppressant to receive FDA approval for treatment of worsening relapsing-remitting, secondary progressive, and progressive-relapsing multiple sclerosis (MS) is a DNA topoisomerase II inhibitor that has been associated with the development of acute promyelocytic myelogenous leukemia (APML). Central nervous system APML is a rare site of extramedullary involvement following mitoxantrone therapy. We report a patient with history of multiple sclerosis who developed bilateral optic nerve involvement as the primary manifestation of APML relapse following mitoxantrone treatment.
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Affiliation(s)
- Melissa W Ko
- Department of Neurology, State University of New York Upstate Medical University, Syracuse, NY, United States.
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162
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Ono M, Watanabe T, Shimizu C, Hiramoto N, Goto Y, Yonemori K, Kouno T, Ando M, Tamura K, Katsumata N, Fujiwara Y. Therapy-Related Acute Promyelocytic Leukemia Caused by Hormonal Therapy and Radiation in a Patient with Recurrent Breast Cancer. Jpn J Clin Oncol 2008; 38:567-70. [DOI: 10.1093/jjco/hyn057] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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163
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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: 4.3] [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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164
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Soejima T, Iida KI, Qin T, Taniai H, Seki M, Yoshida SI. Method To Detect Only Live Bacteria during PCR Amplification. J Clin Microbiol 2008; 46:2305-13. [PMID: 18448692 PMCID: PMC2446937 DOI: 10.1128/jcm.02171-07] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 12/23/2007] [Accepted: 04/19/2008] [Indexed: 11/20/2022] Open
Abstract
Ethidium monoazide (EMA) is a DNA cross-linking agent and eukaryotic topoisomerase II poison. We previously reported that the treatment of EMA with visible light irradiation (EMA + Light) directly cleaved chromosomal DNA of Escherichia coli (T. Soejima, K. Iida, T. Qin, H. Taniai, M. Seki, A. Takade, and S. Yoshida, Microbiol. Immunol. 51:763-775, 2007). Herein, we report that EMA + Light randomly cleaved chromosomal DNA of heat-treated, but not live, Listeria monocytogenes cells within 10 min of treatment. When PCR amplified DNA that was 894 bp in size, PCR final products from 10(8) heat-treated L. monocytogenes were completely suppressed by EMA + Light. When target DNA was short (113 bp), like the hly gene of L. monocytogenes, DNA amplification was not completely suppressed by EMA + Light only. Thus, we used DNA gyrase/topoisomerase IV and mammalian topoisomerase poisons (here abbreviated as T-poisons) together with EMA + Light. T-poisons could penetrate heat-treated, but not live, L. monocytogenes cells within 30 min to cleave chromosomal DNA by poisoning activity. The PCR product of the hly gene from 10(8) heat-treated L. monocytogenes cells was inhibited by a combination of EMA + Light and T-poisons (EMA + Light + T-poisons), but those from live bacteria were not suppressed. As a model for clinical application to bacteremia, we tried to discriminate live and antibiotic-treated L. monocytogenes cells present in human blood. EMA + Light + T-poisons completely suppressed the PCR product from 10(3) to 10(7) antibiotic-treated L. monocytogenes cells but could detect 10(2) live bacteria. Considering the prevention and control of food poisoning, this method was applied to discriminate live and heat-treated L. monocytogenes cells spiked into pasteurized milk. EMA + Light + T-poisons inhibited the PCR product from 10(3) to 10(7) heat-treated cells but could detect 10(1) live L. monocytogenes cells. Our method is useful in clinical as well as food hygiene tests.
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Affiliation(s)
- Takashi Soejima
- Department of Bacteriology, Faculty of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
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165
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Cellular processing pathways contribute to the activation of etoposide-induced DNA damage responses. DNA Repair (Amst) 2008; 7:452-63. [PMID: 18206427 DOI: 10.1016/j.dnarep.2007.12.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2007] [Revised: 11/19/2007] [Accepted: 12/01/2007] [Indexed: 11/23/2022]
Abstract
Cytotoxic action (tumor cell killing) and carcinogenic side effect (therapy-related secondary leukemia) of etoposide are closely related to its ability in stabilizing topoisomerase II cleavable complex (TOP2cc), a unique form of protein-linked DNA break. How cells process and detect TOP2-concealed DNA damage for the activation of downstream cellular responses remains unclear. Here, we showed proteasomal degradation of both TOP2 isozymes in a transcription-dependent manner upon etoposide treatment. Downregulation of TOP2 was preferentially associated with proteasomal removal of TOP2 in TOP2cc rather than proteolysis of free TOP2. Interestingly, blockage of TOP2 downregulation in TOP2cc also caused reduction in etoposide-induced activation of DNA damage molecules, an observation suggesting that the processing pathways of TOP2cc are involved in activation of etoposide-induced cellular responses. In this regard, we observed two TOP2cc processing pathways, replication- and transcription-initiated processing (RIP and TIP) with proteasome involved in the latter. Importantly, two processing pathways contributed to differential activation of various DNA damage signaling and downstream cellular responses. Etoposide-induced phosphorylation of p53 relied mainly on RIP, whereas activation of Chk1, Chk2 depended largely on TIP. Both RIP and TIP played roles in activating non-homologous end joining pathway, while only RIP modulated etoposide-induced cell killing in a p53-dependent manner. Collectively, our results are consistent with the notion that protein-linked DNA breakage (e.g., TOP2cc) requires processing pathways for initiating downstream DNA damage detection, repair as well as cell death programs.
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166
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Ramkumar B, Chadha MK, Barcos M, Sait SNJ, Heyman MR, Baer MR. Acute promyelocytic leukemia after mitoxantrone therapy for multiple sclerosis. ACTA ACUST UNITED AC 2008; 182:126-9. [PMID: 18406875 DOI: 10.1016/j.cancergencyto.2008.01.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2007] [Accepted: 01/08/2008] [Indexed: 11/30/2022]
Abstract
Mitoxantrone is a DNA-topoisomerase 2 inhibitor used as a single agent for treatment of relapsing-remitting or progressive multiple sclerosis (MS). We present here two patients treated with mitoxantrone for MS who subsequently developed acute promyelocytic leukemia (APL). These constitute, to our knowledge, the eighth and ninth reports of APL in patients treated with mitoxantrone for MS. Topoisomerase 2 inhibitors are associated with therapy-related acute myeloid leukemia (t-AML) with 11q23 abnormalities, but therapy-related APL (t-APL) is less common, and documentation of nine cases of t-APL after mitoxantrone therapy for MS suggests a specific association.
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Affiliation(s)
- Bhuvaneswari Ramkumar
- Department of Internal Medicine, Rochester General Hospital, Rochester, NY 14621, USA
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167
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Therapy-related acute myeloid leukaemia with mutated NPM1: treatment induced or de novo in origin? Leukemia 2008; 22:891-2. [DOI: 10.1038/leu.2008.44] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
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168
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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: 1.6] [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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169
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Starvation-dependent differential stress resistance protects normal but not cancer cells against high-dose chemotherapy. Proc Natl Acad Sci U S A 2008; 105:8215-20. [PMID: 18378900 DOI: 10.1073/pnas.0708100105] [Citation(s) in RCA: 397] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Strategies to treat cancer have focused primarily on the killing of tumor cells. Here, we describe a differential stress resistance (DSR) method that focuses instead on protecting the organism but not cancer cells against chemotherapy. Short-term starved S. cerevisiae or cells lacking proto-oncogene homologs were up to 1,000 times better protected against oxidative stress or chemotherapy drugs than cells expressing the oncogene homolog Ras2(val19). Low-glucose or low-serum media also protected primary glial cells but not six different rat and human glioma and neuroblastoma cancer cell lines against hydrogen peroxide or the chemotherapy drug/pro-oxidant cyclophosphamide. Finally, short-term starvation provided complete protection to mice but not to injected neuroblastoma cells against a high dose of the chemotherapy drug/pro-oxidant etoposide. These studies describe a starvation-based DSR strategy to enhance the efficacy of chemotherapy and suggest that specific agents among those that promote oxidative stress and DNA damage have the potential to maximize the differential toxicity to normal and cancer cells.
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170
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Flaig TW, Tangen CM, Hussain MHA, Stadler WM, Raghavan D, Crawford ED, Glodé LM. Randomization reveals unexpected acute leukemias in Southwest Oncology Group prostate cancer trial. J Clin Oncol 2008; 26:1532-6. [PMID: 18349405 DOI: 10.1200/jco.2007.13.4197] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Southwest Oncology Group (SWOG) study 9921 is a randomized, phase III, intergroup study to define the role of adjuvant chemotherapy in patients with high-risk prostate cancer. PATIENTS AND METHODS We allocated 983 patients with prostate cancer with high-risk features to receive 2 years of androgen-deprivation therapy (ADT) with or without six cycles of mitoxantrone (12 mg/m(2)) after prostatectomy. RESULTS In January 2007, SWOG 9921 was closed to further accrual after three cases of acute myelogenous leukemia (AML) were reported of a total of 487 patients in the mitoxantrone treatment arm. The key cytogenetic features of these cases included inv(16) in the first case, t(15;17) in the second, and del(5) in the third case. Time from the start of mitoxantrone to the detection of AML was 13, 48, and 72 months, respectively. Before SWOG 9921, there were no cases of mitoxantrone-induced AML reported in patients treated for prostate cancer. CONCLUSION The emergence of this possible pattern of secondary malignancy emphasizes the importance of randomized controlled trials in defining safety and efficacy of new approaches for patients in the adjuvant setting.
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Affiliation(s)
- Thomas W Flaig
- Department of Medicine, University of Colorado Health Science Center, Mail Stop 8117, P.O. Box 6511, Aurora, CO 80045-0511, USA.
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172
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Böttger S, Jerszyk E, Low B, Walker C. Genotoxic Stress–Induced Expression of p53 and Apoptosis in Leukemic Clam Hemocytes with Cytoplasmically Sequestered p53. Cancer Res 2008; 68:777-82. [DOI: 10.1158/0008-5472.can-06-0968] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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173
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Deweese JE, Osheroff MA, Osheroff N. DNA Topology and Topoisomerases: Teaching a "Knotty" Subject. BIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION : A BIMONTHLY PUBLICATION OF THE INTERNATIONAL UNION OF BIOCHEMISTRY AND MOLECULAR BIOLOGY 2008; 37:2-10. [PMID: 19225573 PMCID: PMC2643378 DOI: 10.1002/bmb.20244] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
DNA is essentially an extremely long double-stranded rope in which the two strands are wound about one another. As a result, topological properties of the genetic material, including DNA underwinding and overwinding, knotting, and tangling, profoundly influence virtually every major nucleic acid process. Despite the importance of DNA topology, it is a conceptionally difficult subject to teach, because it requires students to visualize three-dimensional relationships. This article will familiarize the reader with the concept of DNA topology and offer practical approaches and demonstrations to teaching this "knotty" subject in the classroom. Furthermore, it will discuss topoisomerases, the enzymes that regulate the topological state of DNA in the cell. These ubiquitous enzymes perform a number of critical cellular functions by generating transient breaks in the double helix. During this catalytic event, topoisomerases maintain genomic stability by forming covalent phosphotyrosyl bonds between active site residues and the newly generated DNA termini. Topoisomerases are essential for cell survival. However, because they cleave the genetic material, these enzymes also have the potential to fragment the genome. This latter feature of topoisomerases is exploited by some of the most widely prescribed anticancer and antibacterial drugs currently in clinical use. Finally, in addition to curing cancer, topoisomerase action also has been linked to the induction of specific types of leukemia.
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Affiliation(s)
- Joseph E. Deweese
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
| | | | - Neil Osheroff
- Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
- Department of Medicine (Hematology/Oncology), Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146
- To whom correspondence should be addressed: Department of Biochemistry, 654 Robinson Research Building, Vanderbilt University School of Medicine, Nashville, TN 37232-0146. Tel: 1-615-322-4338; Fax: 1-615-343-1166; E-Mail:
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Abstract
Therapy-related acute myelogenous leukemia and myelodysplastic syndrome (t-AML/MDS) are increasing in prevalence with aging of the population and improved survival of patients treated with chemotherapy or radiotherapy for other malignancies. Research focused on the pathogenesis of t-AML/MDS will provide insight into the pathogenesis of de novo AML/MDS. Participation in clinical trials should be encouraged for this patient population because results with available treatment options are clearly suboptimal.
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Affiliation(s)
- Gautam Borthakur
- Department of Leukemia, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
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175
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López-Lázaro M, Willmore E, Jobson A, Gilroy KL, Curtis H, Padget K, Austin CA. Curcumin induces high levels of topoisomerase I- and II-DNA complexes in K562 leukemia cells. JOURNAL OF NATURAL PRODUCTS 2007; 70:1884-1888. [PMID: 18076140 DOI: 10.1021/np070332i] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Recent data suggest that curcumin, a phytochemical with cancer chemopreventive potential, might be useful in the treatment of several solid and hematological malignancies. DNA topoisomerases (topos) are the target of several drugs commonly used in cancer chemotherapy. These drugs induce topo-DNA complexes with either topo I or topo II; then cellular processing converts these complexes into permanent DNA strand breaks that trigger cell death. Using the TARDIS in vivo assay, this study shows for the first time that curcumin induces topo I and topo II (alpha and beta)-DNA complexes in K562 leukemia cells. A comparative analysis revealed that the levels of these complexes were higher than those induced by several standard topo I and topo II inhibitors at equitoxic doses. Curcumin-induced topo I and topo II-DNA complexes were prevented by the antioxidant N-acetylcysteine; this suggests that, unlike the standard topo inhibitors, reactive oxygen species may mediate the formation of these complexes. Overall, this work shows that curcumin is capable of inducing topo-DNA complexes in cells with both topo I and topo II and increases the evidence suggesting that this dietary agent has potential to be tested in cancer chemotherapy.
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Affiliation(s)
- Miguel López-Lázaro
- Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle-upon-Tyne, UK
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176
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Zhang P, Li H, Chen D, Ni J, Kang Y, Wang S. Oleanolic acid induces apoptosis in human leukemia cells through caspase activation and poly(ADP-ribose) polymerase cleavage. Acta Biochim Biophys Sin (Shanghai) 2007; 39:803-9. [PMID: 17928930 DOI: 10.1111/j.1745-7270.2007.00335.x] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
It has been shown that Fructus Ligustri Lucidi (FLL), a promising traditional Chinese medicine, can inhibit the growth of tumors. However, the effective component and molecular mechanism of FLL act to inhibit tumor proliferation are unclear. In this study, we demonstrated that oleanolic acid (OA), a principal chemical component of FLL, inhibited the proliferation of human leukemia HL60 cells in culture. MTT assay showed that treatment of HL60 cells with FLL crude extracts or OA dramatically blocked the growth of target tumor cell in a time- and dose-dependent manner. Morphological changes of the nuclei and DNA fragmentation showed that apoptotic cell death occurred in the HL60 cells after treating with FLL extracts (20 mg/ml) or OA (3.65 x 10(-2) mg/ml). Furthermore, flow cytometry assay showed that treatment of HL60 cells with FLL or OA caused an increased accumulation of G(1) and sub-G(1) subpopulations. Western blot analysis showed that caspase-9 and caspase-3 were activated, accompanied by the cleavage of poly(ADP-ribose) polymerase (PARP) in the target cells during FLL- or OA-induced apoptosis. These results suggest that OA acts as the effective component of FLL by exerting its cytotoxicity towards target tumor cells through activation of caspases and cleavage of PARP.
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Affiliation(s)
- Pengxia Zhang
- Department of Histology and Embryology, Guangdong Medical College, Zhanjiang 524023, China
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177
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Hartford C, Yang W, Cheng C, Fan Y, Liu W, Treviño L, Pounds S, Neale G, Raimondi SC, Bogni A, Dolan ME, Pui CH, Relling MV. Genome scan implicates adhesion biological pathways in secondary leukemia. Leukemia 2007; 21:2128-36. [PMID: 17673902 DOI: 10.1038/sj.leu.2404885] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The genetic risk factors for etoposide-induced leukemia with MLL translocations remain largely unknown. To identify genetic risk factors for and novel characteristics of secondary leukemia, we profiled 116,204 single nucleotide polymorphisms (SNPs) in germline and paired leukemic cell DNA from 13 secondary leukemia/myelodysplasia cases and germline DNA from 13 matched and 156 unmatched controls, all with acute lymphoblastic leukemia treated with etoposide. We analyzed global gene expression from a partially overlapping cohort. No single locus was altered in most cases. We discovered 81 regions of loss of heterozygosity (LOH) in leukemic blasts and 309 SNPs whose allele frequencies differed in cases vs controls. Candidate genes were prioritized on the basis of genes whose SNPs or expression differentiated cases from controls or showed LOH or copy number change in germline vs paired blast DNA from the 13 cases. Three biological pathways were altered: adhesion, Wnt signaling and regulation of actin. Validation experiments using a genome scan for etoposide-induced leukemogenic MLL chimeric fusions in 15 HapMap cell lines also implicated genes involved in adhesion, a process linked to de novo leukemogenesis. Independent clinical epidemiologic and in vitro genome-wide approaches converged to identify novel pathways that may contribute to therapy-induced leukemia.
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Affiliation(s)
- C Hartford
- Department of Hematology-Oncology, St Jude Children's Research Hospital, Memphis, TN 38105, USA
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178
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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: 17.6] [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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179
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Zhang L, Rothman N, Li G, Guo W, Yang W, Hubbard AE, Hayes RB, Yin S, Lu W, Smith MT. Aberrations in chromosomes associated with lymphoma and therapy-related leukemia in benzene-exposed workers. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2007; 48:467-74. [PMID: 17584886 DOI: 10.1002/em.20306] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Epidemiological studies show that benzene exposure is associated with an increased incidence of leukemia and perhaps lymphoma. Chromosomal rearrangements are common in these hematopoietic diseases. Translocation t(14;18), the long-arm deletion of chromosome 6 [del(6q)], and trisomy 12 are frequently observed in lymphoma patients. Rearrangements of the MLL gene located on chromosome 11q23, such as t(4;11) and t(6;11), are common in therapy-related leukemias resulting from treatment with topoisomerase II inhibiting drugs. To examine numerical and structural changes in these chromosomes (2, 4, 6, 11, 12, 14, and 18), fluorescence in situ hybridization (FISH) was employed on metaphase spreads from workers exposed to benzene (n = 43) and matched controls (n = 44) from Shanghai, China. Aneuploidy (both monosomy and trisomy) of all seven chromosomes was increased by benzene exposure. Benzene also induced del(6q) in a dose-dependent manner (P(trend) = 0.0002). Interestingly, translocations between chromosomes 14 and 18, t(14;18), known to be associated with follicular non-Hodgkin lymphoma, were increased in the highly exposed workers (P < 0.001). On the other hand, translocations between chromosome 11 and other partner chromosomes that are found in therapy-induced leukemias were not increased. These data add weight to the notion that benzene can induce t(14;18) and del(6q) found in lymphoma, but do not support the idea that benzene induces t(4;11) or t(6;11). However, they do not rule out the possibility that other rearrangements of the MLL gene at chromosome 11q23 may be induced by benzene.
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Affiliation(s)
- Luoping Zhang
- School of Public Health, University of California, Berkeley, California, USA.
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180
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Huang RS, Duan S, Bleibel WK, Kistner EO, Zhang W, Clark TA, Chen TX, Schweitzer AC, Blume JE, Cox NJ, Dolan ME. A genome-wide approach to identify genetic variants that contribute to etoposide-induced cytotoxicity. Proc Natl Acad Sci U S A 2007; 104:9758-63. [PMID: 17537913 PMCID: PMC1887589 DOI: 10.1073/pnas.0703736104] [Citation(s) in RCA: 167] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
Large interindividual variance has been observed in sensitivity to drugs. To comprehensively decipher the genetic contribution to these variations in drug susceptibility, we present a genome-wide model using human lymphoblastoid cell lines from the International HapMap consortium, of which extensive genotypic information is available, to identify genetic variants that contribute to chemotherapeutic agent-induced cytotoxicity. Our model integrated genotype, gene expression, and sensitivity of HapMap cell lines to drugs. Cell lines derived from 30 trios of European descent (Center d'Etude du Polymorphisme Humain population) and 30 trios of African descent (Yoruban population) were used. Cell growth inhibition at increasing concentrations of etoposide for 72 h was determined by using alamarBlue assay. Gene expression on 176 HapMap cell lines (87 Center d'Etude du Polymorphisme Humain population and 89 Yoruban population) was determined by using the Affymetrix GeneChip Human Exon 1.0ST Array. We evaluated associations between genotype and cytotoxicity, genotype and gene expression and correlated gene expression of the identified candidates with cytotoxicity. The analysis identified 63 genetic variants that contribute to etoposide-induced toxicity through their effect on gene expression. These include genes that may play a role in cancer (AGPAT2, IL1B, and WNT5B) and genes not yet known to be associated with sensitivity to etoposide. This unbiased method can be used to elucidate genetic variants contributing to a wide range of cellular phenotypes induced by chemotherapeutic agents.
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Affiliation(s)
| | | | | | - Emily O. Kistner
- Biostatistics Consulting Laboratory, Department of Health Studies, and
| | | | - Tyson A. Clark
- Expression Research, Affymetrix Laboratory, Affymetrix, Inc., Santa Clara, CA 95051
| | - Tina X. Chen
- Expression Research, Affymetrix Laboratory, Affymetrix, Inc., Santa Clara, CA 95051
| | | | - John E. Blume
- Expression Research, Affymetrix Laboratory, Affymetrix, Inc., Santa Clara, CA 95051
| | - Nancy J. Cox
- Section of Genetic Medicine, Department of Medicine, University of Chicago, Chicago, IL 60637; and
| | - M. Eileen Dolan
- *Section of Hematology–Oncology
- To whom correspondence should be addressed. E-mail:
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181
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López-Lazaro M, Willmore E, Austin CA. Cells lacking DNA topoisomerase II beta are resistant to genistein. JOURNAL OF NATURAL PRODUCTS 2007; 70:763-7. [PMID: 17411092 DOI: 10.1021/np060609z] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Evidence suggests that DNA topoisomerases (topos) may be involved in the anticancer and carcinogenic properties attributed to flavonoids. Using the cell-based assay TARDIS, the dietary flavonoids genistein (1) and luteolin (2) have been evaluated as topo I and topo II poisons and catalytic inhibitors in K562 leukemia cells. Both flavonoids induced topo II-DNA complexes, but they did not induce significant levels of topo I-DNA complexes. Genistein decreased the topo II-DNA complexes induced by the topo II poison etoposide, suggestive of a catalytic inhibition of topo II, and luteolin decreased the topo I-DNA complexes induced by the topo I poison camptothecin, indicative of a catalytic inhibition of topo I. Murine transgenic cells lacking topo II beta were resistant to genistein-induced cell growth inhibition (XTT assays) and cytotoxicity (clonogenic assay). High levels of topo II beta-DNA complexes were also observed in K562 cells exposed to genistein. These data suggest that topo II beta has an important function in genistein-induced cell growth inhibition and cell death. The possible role of topoisomerases in the putative anticancer and carcinogenic properties of genistein and luteolin is discussed.
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Affiliation(s)
- Miguel López-Lazaro
- Institute for Cell and Molecular Biosciences, The Medical School, University of Newcastle-upon-Tyne, Newcastle-upon-Tyne, NE2 4HH, United Kingdom
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182
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Jantunen E, Heinonen K, Mahlamäki E, Penttilä K, Kuittinen T, Lehtonen P, Pyörälä M, Hänninen A, Nousiainen T. Secondary acute promyelocytic leukemia: an increasingly common entity. Leuk Lymphoma 2007; 48:190-1. [PMID: 17325866 DOI: 10.1080/10428190600961736] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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183
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Abstract
Chromosome aberrations, in particular translocations and their corresponding gene fusions, have an important role in the initial steps of tumorigenesis; at present, 358 gene fusions involving 337 different genes have been identified. An increasing number of gene fusions are being recognized as important diagnostic and prognostic parameters in malignant haematological disorders and childhood sarcomas. The biological and clinical impact of gene fusions in the more common solid tumour types has been less appreciated. However, an analysis of available data shows that gene fusions occur in all malignancies, and that they account for 20% of human cancer morbidity. With the advent of new and powerful investigative tools that enable the detection of cytogenetically cryptic rearrangements, this proportion is likely to increase substantially.
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Affiliation(s)
- Felix Mitelman
- Lund University, Department of Clinical Genetics, Lund University Hospital, SE-221 85 Lund, Sweden.
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184
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Grau Cat J, Navarro Ferrando JT, Mate Sanz JL, Ribera Santasusana JM. Leucemia promielocítica aguda en un paciente con carcinoma de colon tratado con fluorouracilo. Med Clin (Barc) 2007; 128:478-9. [PMID: 17408544 DOI: 10.1016/s0025-7753(07)72628-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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185
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Coiteux V, Onclercq-Delic R, Fenaux P, Amor-Guéret M. Predisposition to therapy-related acute leukemia with balanced chromosomal translocations does not result from a major constitutive defect in DNA double-strand break end joining. Leuk Res 2007; 31:353-8. [PMID: 16890283 DOI: 10.1016/j.leukres.2006.06.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2006] [Revised: 02/08/2006] [Accepted: 06/02/2006] [Indexed: 12/28/2022]
Abstract
The frequency of acute myeloid leukemia (AML) with balanced chromosomal translocations arising after anticancer therapy with DNA-damaging agents such as DNA topoisomerase II inhibitors has increased over the last two decades. However, factors that predispose to these therapy-related disorders are still poorly defined. It has been reported that DNA double-strand break (DSB) repair by the non-homologous end-joining (NHEJ) pathway is impaired in myeloid leukemia cells. This led us to hypothesize that therapy-related AML (t-AML) may result from individual differences in the repair of DSBs generated by the treatment. We show here that DSB repair is accurate, in vivo, in non-tumoral cells derived from patients who developed t-AML with t(9;11) or t(15;17) translocation after treatment for a first cancer with DNA topoisomerase II inhibitors. These results indicate that a major constitutive defect in the NHEJ pathway is unlikely to predispose to t-AML with balanced chromosomal translocations.
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MESH Headings
- Acute Disease
- Adult
- Aged
- Antineoplastic Combined Chemotherapy Protocols/adverse effects
- Cell Line, Tumor
- Chromosomes, Human, Pair 11/genetics
- Chromosomes, Human, Pair 15/genetics
- Chromosomes, Human, Pair 17/genetics
- Chromosomes, Human, Pair 9/genetics
- DNA Breaks, Double-Stranded/drug effects
- DNA Repair/drug effects
- DNA Topoisomerases, Type II
- Enzyme Inhibitors/pharmacology
- Female
- Humans
- Leukemia, Myeloid/drug therapy
- Leukemia, Myeloid/genetics
- Male
- Middle Aged
- Neoplasms, Second Primary/drug therapy
- Neoplasms, Second Primary/genetics
- Structure-Activity Relationship
- Topoisomerase II Inhibitors
- Translocation, Genetic/genetics
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Affiliation(s)
- Valérie Coiteux
- Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8126, Institut Gustave Roussy, 39 Rue Camille Desmoulins, 94 805 Villejuif Cedex, France
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186
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187
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Arriola E, Rodriguez-Pinilla SM, Lambros MBK, Jones RL, James M, Savage K, Smith IE, Dowsett M, Reis-Filho JS. Topoisomerase II alpha amplification may predict benefit from adjuvant anthracyclines in HER2 positive early breast cancer. Breast Cancer Res Treat 2007; 106:181-9. [PMID: 17260090 DOI: 10.1007/s10549-006-9492-5] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2006] [Accepted: 12/19/2006] [Indexed: 01/17/2023]
Abstract
BACKGROUND TOP2A gene encodes topoisomerase II alpha, the direct molecular target of anthracyclines. This gene is frequently coamplified with HER2. The aims of this study were to analyse the pattern of TOP2A amplification and protein expression in relation to the molecular subgroups of breast cancers; and to define the impact of TOP2A amplification on the outcome of a series of patients homogeneously treated with adjuvant anthracyclines. METHODS A cohort of 245 patients with early breast cancer homogeneously treated with anthracyclines in the adjuvant setting was selected. A tissue microarray containing these cancers was used to determine HER2 and TOP2A gene copy number by means of chromogenic in situ hybridization. Immunohistochemical staining of topoisomerase II alpha was also performed using a monoclonal antibody (Ki-S1). TOP2A amplification and protein expression were correlated with classical prognostic parameters, expression of immunohistochemical markers and with a gene expression profiling classification using surrogate immunohistochemical markers. Kaplan-Meier method was used to construct survival curves and results were compared with log-rank test. RESULTS TOP2A amplification was restricted to tumours with HER2 amplification and was significantly associated with ER positivity. In the subgroup of patients with HER2 amplified tumours, TOP2A amplification predicted a better overall survival and disease free survival (P = 0.028 and 0.026, respectively). On multivariate analysis, TOP2A amplification maintained its predictive value for DFS. CONCLUSION TOP2A amplification is likely to be a useful marker to predict the subset of patients who will benefit from anthracyclines.
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MESH Headings
- Anthracyclines/administration & dosage
- Antigens, Neoplasm/genetics
- Biomarkers, Tumor/genetics
- Breast Neoplasms/drug therapy
- Breast Neoplasms/genetics
- Carcinoma, Ductal, Breast/drug therapy
- Carcinoma, Ductal, Breast/enzymology
- Carcinoma, Ductal, Breast/genetics
- Carcinoma, Lobular/drug therapy
- Carcinoma, Lobular/enzymology
- Carcinoma, Lobular/genetics
- Chemotherapy, Adjuvant
- DNA Topoisomerases, Type II/genetics
- DNA-Binding Proteins/genetics
- Female
- Gene Amplification
- Gene Dosage
- Gene Expression Regulation, Neoplastic
- Humans
- In Situ Hybridization
- Lymphatic Metastasis/genetics
- Poly-ADP-Ribose Binding Proteins
- Predictive Value of Tests
- Prognosis
- Receptor, ErbB-2/genetics
- Treatment Outcome
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Affiliation(s)
- Edurne Arriola
- The Breakthrough Breast Cancer Research Centre, Institute of Cancer Research, Fulham Road, London SW3 6JB, UK
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188
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Hartmann JT, Lipp HP. Camptothecin and podophyllotoxin derivatives: inhibitors of topoisomerase I and II - mechanisms of action, pharmacokinetics and toxicity profile. Drug Saf 2007; 29:209-30. [PMID: 16524321 DOI: 10.2165/00002018-200629030-00005] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Camptothecins represent an established class of effective agents that selectively target topoisomerase I by trapping the catalytic intermediate of the topoisomerase I-DNA reaction, the cleavage complex. The water-soluble salt camptothecin-sodium - introduced in early trials in the 1960s - was highly toxic in animals, whereas the semisynthetic derivatives irinotecan and topotecan did not cause haemorrhagic cystitis because of their higher physicochemical stability and solubility at lower pH values. Myelosuppression, neutropenia and, to a lesser extent, thrombocytopenia are dose-limiting toxic effects of topotecan. In contrast to the structurally-related topotecan, irinotecan is a prodrug which has to be converted to SN-38, its active form. SN-38 is inactivated by conjugation, thus patients with Gilbert's syndrome and other forms of genetic glucuronidation deficiency are at an increased risk of irinotecan-induced adverse effects, such as neutropenia and diarrhoea. The cytotoxic mechanism of podophyllotoxin is the inhibition of topoisomerase II. Common adverse effects of etoposide include dose-limiting myelosuppression. Hypersensitivity reactions are more common with etoposide and teniposide than with etoposide phosphate because the formulations of the former contain sensitising solubilisers. Leukopenia and thrombocytopenia occur in 65% and 80%, respectively, of patients after administration of conventional doses of teniposide. Anorexia, vomiting and diarrhoea are generally of mild severity after administration of conventional doses of topoisomerase II inhibitors. Clinical pharmacokinetic studies have revealed substantial interindividual variabilities regarding the area under the concentration-time curve values and steady-state concentrations for all drugs reviewed in this article. Irinotecan, etoposide and teniposide are degraded via complex metabolic pathways. In contrast, topotecan primarily undergoes renal excretion. Regarding etoposide and teniposide, the extent of catechol formation over time during drug metabolism may be associated with a higher risk for secondary malignancies.
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Affiliation(s)
- Jörg T Hartmann
- Department of Oncology/Hematology/Immunology/Pneumology/Rheumatology, Eberhard Karls University Tübingen, UKT - Medical Center II, Tübingen, Germany.
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189
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Vitoux D, Nasr R, de The H. Acute promyelocytic leukemia: New issues on pathogenesis and treatment response. Int J Biochem Cell Biol 2007; 39:1063-70. [PMID: 17468032 DOI: 10.1016/j.biocel.2007.01.028] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2006] [Revised: 12/21/2006] [Accepted: 01/01/2007] [Indexed: 11/15/2022]
Abstract
Pathogenesis of acute promyelocytic leukemia appears to be one of the best understood among human malignancies. The ability of retinoic acid (RA) and arsenic trioxide to directly target the oncogenic promyelocytic leukemia-retinoic receptor A (PML-RARA) fusion protein also made this disease the first model for oncogene-targeted therapies. A set of recent data has significantly increased the complexity of our view of acute promyelocytic leukemia pathogenesis, as well as of therapeutic response. This review summarizes and discusses these findings, which yield novels questions and models.
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MESH Headings
- Arsenic Trioxide
- Arsenicals/pharmacology
- Arsenicals/therapeutic use
- Humans
- Leukemia, Promyelocytic, Acute/drug therapy
- Leukemia, Promyelocytic, Acute/genetics
- Leukemia, Promyelocytic, Acute/pathology
- Models, Biological
- Oncogene Proteins, Fusion/antagonists & inhibitors
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/metabolism
- Oxides/pharmacology
- Oxides/therapeutic use
- Tretinoin/pharmacology
- Tretinoin/therapeutic use
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Affiliation(s)
- Dominique Vitoux
- CNRS UMR 7151, Université Paris 7, Equipe labellisée par la Ligue Nationale contre le Cancer, Hôpital Saint-Louis (APHP), 1 av Claude Vellefaux, 75475 Paris Cedex 10, France.
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190
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Ennishi D, Sezaki N, Senoo T, Terui Y, Hatake K, Hino N. A case of acute promyelocytic leukemia during gefitinib treatment. Int J Hematol 2006; 84:284-5. [PMID: 17020873 DOI: 10.1532/ijh97.06149] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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191
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Ledda A, Caocci G, Spinicci G, Cocco E, Mamusa E, La Nasa G. Two new cases of acute promyelocytic leukemia following mitoxantrone treatment in patients with multiple sclerosis. Leukemia 2006; 20:2217-8. [PMID: 17051242 DOI: 10.1038/sj.leu.2404443] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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192
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Malik M, Nitiss KC, Enriquez-Rios V, Nitiss JL. Roles of nonhomologous end-joining pathways in surviving topoisomerase II-mediated DNA damage. Mol Cancer Ther 2006; 5:1405-14. [PMID: 16818498 DOI: 10.1158/1535-7163.mct-05-0263] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Topoisomerase II is a target for clinically active anticancer drugs. Drugs targeting these enzymes act by preventing the religation of enzyme-DNA covalent complexes leading to protein-DNA adducts that include single- and double-strand breaks. In mammalian cells, nonhomologous repair pathways are critical for repairing topoisomerase II-mediated DNA damage. Because topoisomerase II-targeting agents, such as etoposide, can also induce chromosomal translocations that can lead to secondary malignancies, understanding nonhomologous repair of topoisomerase II-mediated DNA damage may help to define strategies that limit this critical side effect on an important class of anticancer agents. Using Saccharomyces cerevisiae as a model eukaryote, we have determined the contribution of genes required for nonhomologous end-joining (NHEJ) for repairing DNA damage arising from treatment with topoisomerase II poisons, such as etoposide and 4'-(9-acridinylamino)methanesulfon-m-anisidide (mAMSA). To increase cellular sensitivity to topoisomerase II poisons, we overexpressed either wild-type or drug-hypersensitive alleles of yeast topoisomerase II. Using this approach, we found that yku70 (hdf1), yku80 (hdf2), and other genes required for NHEJ were important for cell survival following exposure to etoposide. The clearest increase in sensitivity was observed with cells overexpressing an etoposide-hypersensitive allele of TOP2 (Ser740Trp). Hypersensitivity was also seen in some end-joining defective mutants exposed to the intercalating agent mAMSA, although the increase in sensitivity was less pronounced. To confirm that the increase in sensitivity was not solely due to the elevated expression of TOP2 or due to specific effects of the drug-hypersensitive TOP2 alleles, we also found that deletion of genes required for NHEJ increased the sensitivity of rad52 deletions to both etoposide and mAMSA. Taken together, these results show a clear role for NHEJ in the repair of DNA damage induced by topoisomerase II-targeting agents and suggest that this pathway may participate in translocations generated by drugs, such as etoposide.
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Affiliation(s)
- Mobeen Malik
- Department of Molecular Pharmacology, St. Jude Children's Research Hospital, 332 North Lauderdale, Memphis, TN 38105, USA
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193
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Casorelli I, Tenedini E, Tagliafico E, Blasi MF, Giuliani A, Crescenzi M, Pelosi E, Testa U, Peschle C, Mele L, Diverio D, Breccia M, Lo-Coco F, Ferrari S, Bignami M. Identification of a molecular signature for leukemic promyelocytes and their normal counterparts: focus on DNA repair genes. Leukemia 2006; 20:1978-88. [PMID: 16990782 DOI: 10.1038/sj.leu.2404376] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Acute promyelocytic leukemia (APL) is a clonal expansion of hematopoietic precursors blocked at the promyelocytic stage. Gene expression profiles of APL cells obtained from 16 patients were compared to eight samples of CD34+-derived normal promyelocytes. Malignant promyelocytes showed widespread changes in transcription in comparison to their normal counterpart and 1020 differentially expressed genes were identified. Discriminating genes include transcriptional regulators (FOS, JUN and HOX genes) and genes involved in cell cycle and DNA repair. The strong upregulation in APL of some transcripts (FLT3, CD33, CD44 and HGF) was also confirmed at protein level. Interestingly, a trend toward a transcriptional repression of genes involved in different DNA repair pathways was found in APL and confirmed by real-time polymerase chain reactor (PCR) in a new set of nine APLs. Our results suggest that both inefficient base excision repair and recombinational repair might play a role in APLs development. To investigate the expression pathways underlying the development of APL occurring as a second malignancy (sAPL), we included in our study eight cases of sAPL. Although both secondary and de novo APL were characterized by a strong homogeneity in expression profiling, we identified a small set of differentially expressed genes that discriminate sAPL from de novo cases.
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MESH Headings
- Adult
- Antigens, CD/genetics
- Antigens, CD/metabolism
- Antigens, CD34/metabolism
- Antigens, Differentiation, Myelomonocytic/genetics
- Antigens, Differentiation, Myelomonocytic/metabolism
- Cluster Analysis
- DNA Repair/genetics
- Female
- Flow Cytometry
- Gene Expression Regulation, Leukemic
- Granulocyte Precursor Cells/pathology
- Granulocyte Precursor Cells/physiology
- Humans
- Hyaluronan Receptors/genetics
- Hyaluronan Receptors/metabolism
- Immunophenotyping
- Leukemia, Promyelocytic, Acute/genetics
- Leukemia, Promyelocytic, Acute/pathology
- Male
- Middle Aged
- Oligonucleotide Array Sequence Analysis
- Reverse Transcriptase Polymerase Chain Reaction
- Sialic Acid Binding Ig-like Lectin 3
- Transcription, Genetic
- fms-Like Tyrosine Kinase 3/genetics
- fms-Like Tyrosine Kinase 3/metabolism
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Affiliation(s)
- I Casorelli
- Section of Experimental Carcinogenesis, Department of Environment and Primary Prevention, Istituto Superiore di Sanità, Rome, Italy
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194
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Pedersen-Bjergaard J, Christiansen DH, Desta F, Andersen MK. Alternative genetic pathways and cooperating genetic abnormalities in the pathogenesis of therapy-related myelodysplasia and acute myeloid leukemia. Leukemia 2006; 20:1943-9. [PMID: 16990778 DOI: 10.1038/sj.leu.2404381] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Alternative genetic pathways were previously outlined in the pathogenesis of therapy-related myelodysplasia (t-MDS) and acute myeloid leukemia (t-AML) based on cytogenetic characteristics. Some of the chromosome aberrations, the recurrent balanced translocations or inversions, directly result in chimeric rearrangement of genes for hematopoietic transcription factors (class II mutations) which disturb cellular differentiation. Other genetic abnormalities in t-MDS and t-AML comprise activating point mutations or internal tandem duplications of genes involved in signal transduction as tyrosine kinase receptors or genes more downstream in the RAS-BRAF pathway (class I mutations). The alternative genetic pathways of t-MDS and t-AML can now be further characterized by a different clustering of six individual class I mutations and mutations of AML1 and p53 in the various pathways. In addition, there is a significant association between class I and class II mutations possibly indicating cooperation in leukemogenesis, and between mutations of AML1 and RAS related to subsequent progression from t-MDS to t-AML. Therapy-related and de novo myelodysplasia and acute myeloid leukemia seem to share genetic pathways, and surprisingly gene mutations were in general not more frequent in patients with t-MDS or t-AML as compared to similar cases of de novo MDS and AML studied previously.
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Affiliation(s)
- J Pedersen-Bjergaard
- The Chromosome Laboratory, Section of Hematology/Oncology, Department of Clinical Genetics, Juliane Marie Center, Copenhagen, Denmark.
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195
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Abstract
Recurring chromosome abnormalities are strongly associated with certain subtypes of leukemia, lymphoma and sarcomas. More recently, their potential involvement in carcinomas, i.e. prostate cancer, has been recognized. They are among the most important factors in determining disease prognosis, and in many cases, identification of these chromosome abnormalities is crucial in selecting appropriate treatment protocols. Chromosome translocations are frequently observed in both de novo and therapy-related acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). The mechanisms that result in such chromosome translocations in leukemia and other cancers are largely unknown. Genomic breakpoints in all the common chromosome translocations in leukemia, including t(4;11), t(9;11), t(8;21), inv(16), t(15;17), t(12;21), t(1;19) and t(9;22), have been cloned. Genomic breakpoints tend to cluster in certain intronic regions of the relevant genes including MLL, AF4, AF9, AML1, ETO, CBFB, MYHI1, PML, RARA, TEL, E2A, PBX1, BCR and ABL. However, whereas the genomic breakpoints in MLL tend to cluster in the 5' portion of the 8.3 kb breakpoint cluster region (BCR) in de novo and adult patients and in the 3' portion in infant leukemia patients and t-AML patients, those in both the AML1 and ETO genes occur in the same clustered regions in both de novo and t-AML patients. These differences may reflect differences in the mechanisms involved in the formation of the translocations. Specific chromatin structural elements, such as in vivo topoisomerase II (topo II) cleavage sites, DNase I hypersensitive sites and scaffold attachment regions (SARs) have been mapped in the breakpoint regions of the relevant genes. Strong in vivo topo II cleavage sites and DNase I hypersensitive sites often co-localize with each other and also with many of the BCRs in most of these genes, whereas SARs are associated with BCRs in MLL, AF4, AF9, AML1, ETO and ABL, but not in the BCR gene. In addition, the BCRs in MLL, AML1 and ETO have the lowest free energy level for unwinding double strand DNA. Virtually all chromosome translocations in leukemia that have been analyzed to date show no consistent homologous sequences at the breakpoints, whereas a strong non-homologous end joining (NHEJ) repair signature exists at all of these chromosome translocation breakpoint junctions; this includes small deletions and duplications in each breakpoint, and micro-homologies and non-template insertions at genomic junctions of each chromosome translocation. Surprisingly, the size of these deletions and duplications in the same translocation is much larger in de novo leukemia than in therapy-related leukemia. We propose a non-homologous chromosome recombination model as one of the mechanisms that results in chromosome translocations in leukemia. The topo II cleavage sites at open chromatin regions (DNase I hypersensitive sites), SARs or the regions with low energy level are vulnerable to certain genotoxic or other agents and become the initial breakage sites, which are followed by an excision end joining repair process.
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Affiliation(s)
- Yanming Zhang
- Section of Hematology/Oncology, Department of Medicine, University of Chicago, 5841 S. Maryland Ave., Chicago, IL, USA
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196
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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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197
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Povirk LF. Biochemical mechanisms of chromosomal translocations resulting from DNA double-strand breaks. DNA Repair (Amst) 2006; 5:1199-212. [PMID: 16822725 DOI: 10.1016/j.dnarep.2006.05.016] [Citation(s) in RCA: 98] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Exposure of mammalian cells to agents that induce DNA double-strand breaks typically results in both reciprocal and nonreciprocal chromosome translocations. Over the past decade, breakpoint junctions of a significant number of translocations and other genomic rearrangements, both in clinical tumors and in experimental models, have been analyzed at the DNA sequence level. Based on these data, reasonable inferences regarding the biochemical mechanisms involved in translocations can be drawn. In a few cases, breakpoints have been shown to correlate with sites of double-strand cleavage by agents to which the cells or patients have been exposed, including exogenous rare-cutting endonucleases, radiomimetic compounds, and topoisomerase inhibitors. These results confirm that translocations primarily reflect misjoining of the exchanged ends of two or more double-strand breaks. Many junctions show significant loss of DNA sequence at the breakpoints, suggesting exonucleolytic degradation of DNA ends prior to joining. The size and frequency of these deletions varies widely, both between experimental systems, and among individual events in a single system. Homologous recombination between repetitive DNA sequences does not appear to be a major pathway for translocations associated with double-strand breaks. Rather, the general features of the junction sequences, particularly the high frequency small terminal deletions, the apparent splicing of DNA ends at microhomologies, and gap-filling on aligned double-strand break ends, are consistent with the known biochemical properties of the classical nonhomologous end joining pathway involving DNA-dependent protein kinase, XRCC4 and DNA ligase IV. Nevertheless, cells with deficiencies in this pathway still exhibit translocations, with grossly similar junction sequences, suggesting an alternative but less conservative end joining pathway. Although evidence for participation of specific DNA end processing enzymes in formation of translocations is largely circumstantial, likely candidates include DNA polymerases lambda and mu, Artemis nuclease, polynucleotide kinase/phosphatase, tyrosyl-DNA phosphodiesterase, DNase III, Werner syndrome protein, and the Mre11/Rad50/NBS1 complex.
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Affiliation(s)
- Lawrence F Povirk
- Department of Pharmacology and Toxicology, Virginia Commonwealth University, Richmond, VA 23298, USA.
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198
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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: 2.4] [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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199
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Au WY, Chan LC, Liang R, Kwong YL. Myelodysplastic syndrome and acute myeloid leukemia after treatment with fludarabine, mitoxantrone, and dexamethasone. Am J Hematol 2006; 81:471-3. [PMID: 16680740 DOI: 10.1002/ajh.20599] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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200
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Borges AC, Knebel F, Eddicks S, Bondke HJ, Baumann G. [Echocardiographic evaluation to select patients for cardiac resynchronization therapy]. Herzschrittmacherther Elektrophysiol 2006; 17 Suppl 1:I63-72. [PMID: 16598624 DOI: 10.1007/s00399-006-1110-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Wide QRS complex and asynchronous myocardial contraction in heart failure are associated with poor prognosis. Resynchronization can be achieved by biventricular pacing (BVP), which leads to hemodynamic and clinical improvement and reverse remodeling, and may improve survival. However, there is a substantial subset of patients with wide QRS complexes in the electrocardiogram who does not improve despite BVP, and there are findings which suggest that resynchronization therapy may be also beneficial for heart failure patients with normal QRS duration. QRS width predicts the benefit of BVP only with limitation and only correlates weakly with echocardiographically determined myocardial asynchrony. Determination of asynchrony by tissue Doppler echocardiography seems to be the best predictor for improvement after BVP, although no consensus on the optimal method to assess asynchrony has yet been achieved. To date, most studies evaluating tissue Doppler echo in BVP were performed retrospectively and only one prospective study with patient selection for BVP according to echocardiography and electrocardiography criteria of asynchrony has been published. These new echocardiographic tools will help to prospectively select patients for BVP, help to guide implantation and to optimize device programming.
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Affiliation(s)
- A C Borges
- Medizinische Klinik der Charité, Charité Campus Mitte-Universitätsmedizin Berlin, Schumannstr. 20-21, 10117 Berlin.
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