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Mason NR, Cahill H, Diamond Y, McCleary K, Kotecha RS, Marshall GM, Mateos MK. Down syndrome-associated leukaemias: current evidence and challenges. Ther Adv Hematol 2024; 15:20406207241257901. [PMID: 39050114 PMCID: PMC11268035 DOI: 10.1177/20406207241257901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 05/13/2024] [Indexed: 07/27/2024] Open
Abstract
Children with Down syndrome (DS) are at increased risk of developing haematological malignancies, in particular acute megakaryoblastic leukaemia and acute lymphoblastic leukaemia. The microenvironment established by abnormal haematopoiesis driven by trisomy 21 is compounded by additional genetic and epigenetic changes that can drive leukaemogenesis in patients with DS. GATA-binding protein 1 (GATA1) somatic mutations are implicated in the development of transient abnormal myelopoiesis and the progression to myeloid leukaemia of DS (ML-DS) and provide a model of the multi-step process of leukaemogenesis in DS. This review summarises key genetic drivers for the development of leukaemia in patients with DS, the biology and treatment of ML-DS and DS-associated acute lymphoblastic leukaemia, late effects of treatments for DS-leukaemias and the focus for future targeted therapy.
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Affiliation(s)
- Nicola R. Mason
- Kids Cancer Centre, Sydney Children’s Hospital, Randwick, NSW, Australia
| | - Hilary Cahill
- Kids Cancer Centre, Sydney Children’s Hospital, Randwick, NSW, Australia
| | - Yonatan Diamond
- Kids Cancer Centre, Sydney Children’s Hospital, Randwick, NSW, Australia
| | - Karen McCleary
- Kids Cancer Centre, Sydney Children’s Hospital, Randwick, NSW, Australia
- School of Clinical Medicine, UNSW Medicine and Health, UNSW Sydney, Kensington, NSW, Australia
| | - Rishi S. Kotecha
- Department of Clinical Haematology, Oncology, Blood and Bone Marrow Transplantation, Perth Children’s Hospital, Perth, WA, Australia
- Leukaemia Translational Research Laboratory, Telethon Kids Cancer Centre, Telethon Kids Institute, University of Western Australia, Perth, WA, Australia
- Curtin Medical School, Curtin University, Perth, WA, Australia
| | - Glenn M. Marshall
- Kids Cancer Centre, Sydney Children’s Hospital, Randwick, Randwick, NSW, Australia School of Clinical Medicine, UNSW Medicine and Health, UNSW Sydney, Kensington, NSW, Australia Children’s Cancer Institute, Lowy Cancer Centre, UNSW Sydney, Kensington, NSW, Australia
| | - Marion K. Mateos
- Kids Cancer Centre, Sydney Children’s Hospital, Level 1 South Wing, High Street, Randwick, NSW 2031, Australia
- School of Clinical Medicine, UNSW Medicine and Health, UNSW Sydney, Kensington, NSW, Australia
- Children’s Cancer Institute, Lowy Cancer Centre, UNSW Sydney, Kensington, NSW, Australia
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Kaleta K, Janik K, Rydz L, Wróbel M, Jurkowska H. Bridging the Gap in Cancer Research: Sulfur Metabolism of Leukemic Cells with a Focus on L-Cysteine Metabolism and Hydrogen Sulfide-Producing Enzymes. Biomolecules 2024; 14:746. [PMID: 39062461 PMCID: PMC11274876 DOI: 10.3390/biom14070746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/12/2024] [Accepted: 06/19/2024] [Indexed: 07/28/2024] Open
Abstract
Leukemias are cancers of the blood-forming system, representing a significant challenge in medical science. The development of leukemia cells involves substantial disturbances within the cellular machinery, offering hope in the search for effective selective treatments that could improve the 5-year survival rate. Consequently, the pathophysiological processes within leukemia cells are the focus of critical research. Enzymes such as cystathionine beta-synthase and sulfurtransferases like thiosulfate sulfurtransferase, 3-mercaptopyruvate sulfurtransferase, and cystathionine gamma-lyase play a vital role in cellular sulfur metabolism. These enzymes are essential to maintaining cellular homeostasis, providing robust antioxidant defenses, and supporting cell division. Numerous studies have demonstrated that cancerous processes can alter the expression and activity of these enzymes, uncovering potential vulnerabilities or molecular targets for cancer therapy. Recent laboratory research has indicated that certain leukemia cell lines may exhibit significant changes in the expression patterns of these enzymes. Analysis of the scientific literature and online datasets has confirmed variations in sulfur enzyme function in specific leukemic cell lines compared to normal leukocytes. This comprehensive review collects and analyzes available information on sulfur enzymes in normal and leukemic cell lines, providing valuable insights and identifying new research pathways in this field.
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Affiliation(s)
- Konrad Kaleta
- Students’ Scientific Group of Medical Biochemistry, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Krakow, Poland;
| | - Klaudia Janik
- Chair of Medical Biochemistry, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Krakow, Poland; (K.J.); (L.R.); (M.W.)
| | - Leszek Rydz
- Chair of Medical Biochemistry, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Krakow, Poland; (K.J.); (L.R.); (M.W.)
| | - Maria Wróbel
- Chair of Medical Biochemistry, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Krakow, Poland; (K.J.); (L.R.); (M.W.)
| | - Halina Jurkowska
- Chair of Medical Biochemistry, Faculty of Medicine, Jagiellonian University Medical College, 7 Kopernika St., 31-034 Krakow, Poland; (K.J.); (L.R.); (M.W.)
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3
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Barwe SP, Kolb EA, Gopalakrishnapillai A. Down syndrome and leukemia: An insight into the disease biology and current treatment options. Blood Rev 2024; 64:101154. [PMID: 38016838 DOI: 10.1016/j.blre.2023.101154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 10/31/2023] [Accepted: 11/19/2023] [Indexed: 11/30/2023]
Abstract
Children with Down syndrome (DS) have a 10- to 20-fold greater predisposition to develop acute leukemia compared to the general population, with a skew towards myeloid leukemia (ML-DS). While ML-DS is known to be a subtype with good outcome, patients who relapse face a dismal prognosis. Acute lymphocytic leukemia in DS (DS-ALL) is considered to have poor prognosis. The relapse rate is high in DS-ALL compared to their non-DS counterparts. We have a better understanding about the mutational spectrum of DS leukemia. Studies using animal, embryonic stem cell- and induced pluripotent stem cell-based models have shed light on the mechanism by which these mutations contribute to disease initiation and progression. In this review, we list the currently available treatment strategies for DS-leukemias along with their outcome with emphasis on challenges with chemotherapy-related toxicities in children with DS. We focus on the mechanisms of initiation and progression of leukemia in children with DS and highlight the novel molecular targets with greater success in preclinical trials that have the potential to progress to the clinic.
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Affiliation(s)
- Sonali P Barwe
- Lisa Dean Moseley Institute for Cancer and Blood Disorders, Nemours Children's Health, Wilmington, Delaware, 19803, USA
| | - E Anders Kolb
- Lisa Dean Moseley Institute for Cancer and Blood Disorders, Nemours Children's Health, Wilmington, Delaware, 19803, USA
| | - Anilkumar Gopalakrishnapillai
- Lisa Dean Moseley Institute for Cancer and Blood Disorders, Nemours Children's Health, Wilmington, Delaware, 19803, USA.
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4
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Prieto C, Nguyen DTT, Liu Z, Wheat J, Perez A, Gourkanti S, Chou T, Barin E, Velleca A, Rohwetter T, Chow A, Taggart J, Savino AM, Hoskova K, Dhodapkar M, Schurer A, Barlowe TS, Vu LP, Leslie C, Steidl U, Rabadan R, Kharas MG. Transcriptional control of CBX5 by the RNA binding proteins RBMX and RBMXL1 maintains chromatin state in myeloid leukemia. NATURE CANCER 2021; 2:741-757. [PMID: 34458856 PMCID: PMC8388313 DOI: 10.1038/s43018-021-00220-w] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Accepted: 05/11/2021] [Indexed: 01/08/2023]
Abstract
RNA binding proteins (RBPs) are key arbiters of post-transcriptional regulation and are found to be found dysregulated in hematological malignancies. Here, we identify the RBP RBMX and its retrogene RBMXL1 to be required for murine and human myeloid leukemogenesis. RBMX/L1 are overexpressed in acute myeloid leukemia (AML) primary patients compared to healthy individuals, and RBMX/L1 loss delayed leukemia development. RBMX/L1 loss lead to significant changes in chromatin accessibility, as well as chromosomal breaks and gaps. We found that RBMX/L1 directly bind to mRNAs, affect transcription of multiple loci, including CBX5 (HP1α), and control the nascent transcription of the CBX5 locus. Forced CBX5 expression rescued the RBMX/L1 depletion effects on cell growth and apoptosis. Overall, we determine that RBMX/L1 control leukemia cell survival by regulating chromatin state through their downstream target CBX5. These findings identify a mechanism for RBPs directly promoting transcription and suggest RBMX/L1, as well as CBX5, as potential therapeutic targets in myeloid malignancies.
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Affiliation(s)
- Camila Prieto
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Diu T T Nguyen
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Zhaoqi Liu
- Program for Mathematical Genomics, Department of Systems Biology, Department of Biomedical Informatics, Columbia University Medical Center, New York, NY, USA
- CAS Key Laboratory of Genomic and Precision Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, China National Center for Bioinformation, Beijing 100101, China
| | - Justin Wheat
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY USA
| | - Alexendar Perez
- Computational Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Saroj Gourkanti
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Timothy Chou
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Ersilia Barin
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Anthony Velleca
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Thomas Rohwetter
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Arthur Chow
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - James Taggart
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Angela M Savino
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Katerina Hoskova
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Meera Dhodapkar
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Alexandra Schurer
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Trevor S Barlowe
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Ly P Vu
- Terry Fox Laboratory, British Columbia Cancer Research Centre, Vancouver, BC, Canada; Molecular Biology and Biochemistry, Simon Fraser University, Vancouver, BC, Canada
| | - Christina Leslie
- Computational Biology Program, Memorial Sloan Kettering Cancer Center, New York, NY, USA
| | - Ulrich Steidl
- Department of Cell Biology, Albert Einstein College of Medicine, Bronx, NY USA
| | - Raul Rabadan
- Program for Mathematical Genomics, Department of Systems Biology, Department of Biomedical Informatics, Columbia University Medical Center, New York, NY, USA
| | - Michael G Kharas
- Molecular Pharmacology Program and Center for Cell Engineering, Center for Stem Cell Biology, Center for Experimental Therapeutics, Center for Hematologic Malignancies, Memorial Sloan Kettering Cancer Center, New York, NY, USA
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Bayona-Bafaluy MP, Garrido-Pérez N, Meade P, Iglesias E, Jiménez-Salvador I, Montoya J, Martínez-Cué C, Ruiz-Pesini E. Down syndrome is an oxidative phosphorylation disorder. Redox Biol 2021; 41:101871. [PMID: 33540295 PMCID: PMC7859316 DOI: 10.1016/j.redox.2021.101871] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 12/29/2020] [Accepted: 01/13/2021] [Indexed: 02/07/2023] Open
Abstract
Down syndrome is the most common genomic disorder of intellectual disability and is caused by trisomy of chromosome 21. Several genes in this chromosome repress mitochondrial biogenesis. The goal of this study was to evaluate whether early overexpression of these genes may cause a prenatal impairment of oxidative phosphorylation negatively affecting neurogenesis. Reduction in the mitochondrial energy production and a lower mitochondrial function have been reported in diverse tissues or cell types, and also at any age, including early fetuses, suggesting that a defect in oxidative phosphorylation is an early and general event in Down syndrome individuals. Moreover, many of the medical conditions associated with Down syndrome are also frequently found in patients with oxidative phosphorylation disease. Several drugs that enhance mitochondrial biogenesis are nowadays available and some of them have been already tested in mouse models of Down syndrome restoring neurogenesis and cognitive defects. Because neurogenesis relies on a correct mitochondrial function and critical periods of brain development occur mainly in the prenatal and early neonatal stages, therapeutic approaches intended to improve oxidative phosphorylation should be provided in these periods.
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Affiliation(s)
- M Pilar Bayona-Bafaluy
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, C/ Miguel Servet, 177. 50013, Zaragoza, Spain and C/ Pedro Cerbuna, 12, 50009, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13, 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Rd de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain; Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza. C/ Mariano Esquillor (Edificio I+D), 50018, Zaragoza, Spain.
| | - Nuria Garrido-Pérez
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, C/ Miguel Servet, 177. 50013, Zaragoza, Spain and C/ Pedro Cerbuna, 12, 50009, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13, 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Rd de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain; Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza. C/ Mariano Esquillor (Edificio I+D), 50018, Zaragoza, Spain.
| | - Patricia Meade
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, C/ Miguel Servet, 177. 50013, Zaragoza, Spain and C/ Pedro Cerbuna, 12, 50009, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13, 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Rd de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain; Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza. C/ Mariano Esquillor (Edificio I+D), 50018, Zaragoza, Spain.
| | - Eldris Iglesias
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, C/ Miguel Servet, 177. 50013, Zaragoza, Spain and C/ Pedro Cerbuna, 12, 50009, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13, 50009, Zaragoza, Spain.
| | - Irene Jiménez-Salvador
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, C/ Miguel Servet, 177. 50013, Zaragoza, Spain and C/ Pedro Cerbuna, 12, 50009, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13, 50009, Zaragoza, Spain.
| | - Julio Montoya
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, C/ Miguel Servet, 177. 50013, Zaragoza, Spain and C/ Pedro Cerbuna, 12, 50009, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13, 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Rd de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
| | - Carmen Martínez-Cué
- Departamento de Fisiología y Farmacología. Facultad de Medicina, Universidad de Cantabria. Av. Herrera Oría, 39011, Santander, Spain.
| | - Eduardo Ruiz-Pesini
- Departamento de Bioquímica, Biología Molecular y Celular, Universidad de Zaragoza, C/ Miguel Servet, 177. 50013, Zaragoza, Spain and C/ Pedro Cerbuna, 12, 50009, Zaragoza, Spain; Instituto de Investigación Sanitaria (IIS) de Aragón, Av. San Juan Bosco, 13, 50009, Zaragoza, Spain; Centro de Investigaciones Biomédicas en Rd de Enfermedades Raras (CIBERER), Av. Monforte de Lemos, 3-5, 28029, Madrid, Spain.
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6
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Zuhra K, Augsburger F, Majtan T, Szabo C. Cystathionine-β-Synthase: Molecular Regulation and Pharmacological Inhibition. Biomolecules 2020; 10:E697. [PMID: 32365821 PMCID: PMC7277093 DOI: 10.3390/biom10050697] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 04/24/2020] [Accepted: 04/27/2020] [Indexed: 12/11/2022] Open
Abstract
Cystathionine-β-synthase (CBS), the first (and rate-limiting) enzyme in the transsulfuration pathway, is an important mammalian enzyme in health and disease. Its biochemical functions under physiological conditions include the metabolism of homocysteine (a cytotoxic molecule and cardiovascular risk factor) and the generation of hydrogen sulfide (H2S), a gaseous biological mediator with multiple regulatory roles in the vascular, nervous, and immune system. CBS is up-regulated in several diseases, including Down syndrome and many forms of cancer; in these conditions, the preclinical data indicate that inhibition or inactivation of CBS exerts beneficial effects. This article overviews the current information on the expression, tissue distribution, physiological roles, and biochemistry of CBS, followed by a comprehensive overview of direct and indirect approaches to inhibit the enzyme. Among the small-molecule CBS inhibitors, the review highlights the specificity and selectivity problems related to many of the commonly used "CBS inhibitors" (e.g., aminooxyacetic acid) and provides a comprehensive review of their pharmacological actions under physiological conditions and in various disease models.
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Affiliation(s)
- Karim Zuhra
- Chair of Pharmacology, Section of Medicine, University of Fribourg, 1702 Fribourg, Switzerland; (K.Z.); (F.A.)
| | - Fiona Augsburger
- Chair of Pharmacology, Section of Medicine, University of Fribourg, 1702 Fribourg, Switzerland; (K.Z.); (F.A.)
| | - Tomas Majtan
- Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA;
| | - Csaba Szabo
- Chair of Pharmacology, Section of Medicine, University of Fribourg, 1702 Fribourg, Switzerland; (K.Z.); (F.A.)
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Panagaki T, Randi EB, Szabo C. Role of 3-Mercaptopyruvate Sulfurtransferase in the Regulation of Proliferation and Cellular Bioenergetics in Human Down Syndrome Fibroblasts. Biomolecules 2020; 10:biom10040653. [PMID: 32340322 PMCID: PMC7226246 DOI: 10.3390/biom10040653] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 04/18/2020] [Accepted: 04/21/2020] [Indexed: 12/13/2022] Open
Abstract
Down syndrome (trisomy of human chromosome 21) is a common genetic disorder. Overproduction of the gaseous mediator hydrogen sulfide (H2S) has been implicated in the pathogenesis of neurological and metabolic deficits associated with Down syndrome. Several lines of data indicate that an important enzyme responsible for H2S overproduction in Down syndrome is cystathionine-β-synthase (CBS), an enzyme localized on chromosome 21. The current study explored the possibility that a second H2S-producing enzyme, 3-mercaptopyruvate sulfurtransferase (3-MST), may also contribute to the development of functional deficits of Down syndrome cells. Western blotting analysis demonstrated a significantly higher level of 3-MST protein expression in human Down syndrome fibroblasts compared to cells from healthy control individuals; the excess 3-MST was mainly localized to the mitochondrial compartment. Pharmacological inhibition of 3-MST activity improved mitochondrial electron transport and oxidative phosphorylation parameters (but did not affect the suppressed glycolytic parameters) and enhanced cell proliferation in Down syndrome cells (but not in healthy control cells). The findings presented in the current report suggest that in addition to the indisputable role of CBS, H2S produced from 3-MST may also contribute to the development of mitochondrial metabolic and functional impairments in Down syndrome cells.
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Szabo C. The re-emerging pathophysiological role of the cystathionine-β-synthase - hydrogen sulfide system in Down syndrome. FEBS J 2020; 287:3150-3160. [PMID: 31955501 DOI: 10.1111/febs.15214] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/13/2019] [Accepted: 01/14/2020] [Indexed: 12/21/2022]
Abstract
Down syndrome (DS) is associated with significant perturbances in many morphological and biochemical features. Cystathionine-β-synthase (CBS) is one of the key mammalian enzymes that is responsible for the biological production of the gaseous transmitter hydrogen sulfide (H2 S). When H2 S is overproduced, it can exert detrimental cellular effects, in part due to inhibition of mitochondrial Complex IV activity. An increased expression of CBS and the consequent overproduction of H2 S are well documented in individuals with DS. Two decades ago, it has been proposed that a toxic overproduction of H2 S importantly contributes to the metabolic and neurological deficits associated with DS. However, until recently, this hypothesis has not yet been tested experimentally. Recent data generated in human dermal fibroblasts show that DS cells overproduce H2 S, which, in turn, suppresses mitochondrial Complex IV activity and impairs mitochondrial oxygen consumption and ATP generation. Therapeutic CBS inhibition lifts the tonic (and reversible) suppression of Complex IV: This results in the normalization of mitochondrial function in DS cells. H2 S may also contribute to the cellular dysfunction via several other molecular mechanisms through interactions with various mitochondrial and extramitochondrial molecular targets. The current article provides a historical background of the field, summarizes the recently published data and their potential implications, and outlines potential translational approaches (such as CBS inhibition and H2 S neutralization) and future experimental studies in this re-emerging field of pathobiochemistry.
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Affiliation(s)
- Csaba Szabo
- Chair of Pharmacology, Section of Medicine, University of Fribourg, Switzerland
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9
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Pajares MA, Pérez-Sala D. Mammalian Sulfur Amino Acid Metabolism: A Nexus Between Redox Regulation, Nutrition, Epigenetics, and Detoxification. Antioxid Redox Signal 2018; 29:408-452. [PMID: 29186975 DOI: 10.1089/ars.2017.7237] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
SIGNIFICANCE Transsulfuration allows conversion of methionine into cysteine using homocysteine (Hcy) as an intermediate. This pathway produces S-adenosylmethionine (AdoMet), a key metabolite for cell function, and provides 50% of the cysteine needed for hepatic glutathione synthesis. The route requires the intake of essential nutrients (e.g., methionine and vitamins) and is regulated by their availability. Transsulfuration presents multiple interconnections with epigenetics, adenosine triphosphate (ATP), and glutathione synthesis, polyol and pentose phosphate pathways, and detoxification that rely mostly in the exchange of substrates or products. Major hepatic diseases, rare diseases, and sensorineural disorders, among others that concur with oxidative stress, present impaired transsulfuration. Recent Advances: In contrast to the classical view, a nuclear branch of the pathway, potentiated under oxidative stress, is emerging. Several transsulfuration proteins regulate gene expression, suggesting moonlighting activities. In addition, abnormalities in Hcy metabolism link nutrition and hearing loss. CRITICAL ISSUES Knowledge about the crossregulation between pathways is mostly limited to the hepatic availability/removal of substrates and inhibitors. However, advances regarding protein-protein interactions involving oncogenes, identification of several post-translational modifications (PTMs), and putative moonlighting activities expand the potential impact of transsulfuration beyond methylations and Hcy. FUTURE DIRECTIONS Increasing the knowledge on transsulfuration outside the liver, understanding the protein-protein interaction networks involving these enzymes, the functional role of their PTMs, or the mechanisms controlling their nucleocytoplasmic shuttling may provide further insights into the pathophysiological implications of this pathway, allowing design of new therapeutic interventions. Antioxid. Redox Signal. 29, 408-452.
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Affiliation(s)
- María A Pajares
- 1 Department of Chemical and Physical Biology, Centro de Investigaciones Biológicas (CSIC) , Madrid, Spain .,2 Molecular Hepatology Group, Instituto de Investigación Sanitaria La Paz (IdiPAZ) , Madrid, Spain
| | - Dolores Pérez-Sala
- 1 Department of Chemical and Physical Biology, Centro de Investigaciones Biológicas (CSIC) , Madrid, Spain
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10
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Bista R, Lee DW, Pepper OB, Azorsa DO, Arceci RJ, Aleem E. Disulfiram overcomes bortezomib and cytarabine resistance in Down-syndrome-associated acute myeloid leukemia cells. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2017; 36:22. [PMID: 28143565 PMCID: PMC5286849 DOI: 10.1186/s13046-017-0493-5] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Accepted: 01/26/2017] [Indexed: 02/02/2023]
Abstract
Background Children with Down syndrome (DS) have increased risk for developing AML (DS-AMKL), and they usually experience severe therapy-related toxicities compared to non DS-AMKL. Refractory/relapsed disease has very poor outcome, and patients would benefit from novel, less toxic, therapeutic strategies that overcome resistance. Relapse/resistance are linked to cancer stem cells with high aldehyde dehydrogenase (ALDH) activity. The purpose of the present work was to study less toxic alternative therapeutic agents for relapsed/refractory DS-AMKL. Methods Fourteen AML cell lines including the DS-AMKL CMY and CMK from relapsed/refractory AML were used. Cytarabine (Ara-C), bortezomib (BTZ), disulfiram/copper (DSF/Cu2+) were evaluated for cytotoxicity, depletion of ALDH-positive cells, and resistance. BTZ-resistant CMY and CMK variants were generated by continuous BTZ treatment. Cell viability was assessed using CellTiter-Glo®, ALDH activity by ALDELUORTM, and proteasome inhibition by western blot of ubiquitinated proteins and the Proteasome-Glo™ Chymotrypsin-Like (CT-like) assay, apoptosis by Annexin V Fluos/Propidium iodide staining, and mutations were detected using PCR, cloning and sequencing. Results Ara-C-resistant AML cell lines were sensitive to BTZ and DSF/Cu2+. The Ara-C-resistant DS-AMKL CMY cells had a high percentage of ALDHbright “stem-like” populations that may underlie Ara-C resistance. One percent of these cells were still resistant to BTZ but sensitive to DSF/Cu2+. To understand the mechanism of BTZ resistance, BTZ resistant (CMY-BR) and (CMK-BR) were generated. A novel mutation PSMB5 Q62P underlied BTZ resistance, and was associated with an overexpression of the β5 proteasome subunit. BTZ-resistance conferred increased resistance to Ara-C due to G1 arrest in the CMY-BR cells, which protected the cells from S-phase damage by Ara-C. CMY-BR and CMK-BR cells were cross-resistant to CFZ and MG-132 but sensitive to DSF/Cu2+. In this setting, DSF/Cu2+ induced apoptosis and proteasome inhibition independent of CT-like activity inhibition. Conclusions We provide evidence that DSF/Cu2+ overcomes Ara-C and BTZ resistance in cell lines from DS-AMKL patients. A novel mutation underlying BTZ resistance was detected that may identify BTZ-resistant patients, who may not benefit from treatment with CFZ or Ara-C, but may be responsive to DSF/Cu2+. Our findings support the clinical development of DSF/Cu2+ as a less toxic efficacious treatment approach in patients with relapsed/refractory DS-AMKL. Electronic supplementary material The online version of this article (doi:10.1186/s13046-017-0493-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Ranjan Bista
- Institute of Molecular Medicine at Phoenix Children's Hospital, Phoenix, AZ, USA
| | - David W Lee
- Institute of Molecular Medicine at Phoenix Children's Hospital, Phoenix, AZ, USA.,Department of Child Health, University of Arizona College of Medicine-Phoenix, Biosciences Partnership Building (BSPB), 5th floor, 475 N 5th Street, Phoenix, AZ, 85004, USA
| | - Oliver B Pepper
- Department of Child Health, University of Arizona College of Medicine-Phoenix, Biosciences Partnership Building (BSPB), 5th floor, 475 N 5th Street, Phoenix, AZ, 85004, USA.,Department of Biology and Biochemistry, University of Bath, Bath, UK
| | - David O Azorsa
- Institute of Molecular Medicine at Phoenix Children's Hospital, Phoenix, AZ, USA.,Department of Child Health, University of Arizona College of Medicine-Phoenix, Biosciences Partnership Building (BSPB), 5th floor, 475 N 5th Street, Phoenix, AZ, 85004, USA
| | - Robert J Arceci
- Institute of Molecular Medicine at Phoenix Children's Hospital, Phoenix, AZ, USA.,Department of Child Health, University of Arizona College of Medicine-Phoenix, Biosciences Partnership Building (BSPB), 5th floor, 475 N 5th Street, Phoenix, AZ, 85004, USA
| | - Eiman Aleem
- Institute of Molecular Medicine at Phoenix Children's Hospital, Phoenix, AZ, USA. .,Department of Child Health, University of Arizona College of Medicine-Phoenix, Biosciences Partnership Building (BSPB), 5th floor, 475 N 5th Street, Phoenix, AZ, 85004, USA. .,Department of Zoology, Faculty of Science, Alexandria University, Alexandria, Egypt.
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11
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Kabe Y, Yamamoto T, Kajimura M, Sugiura Y, Koike I, Ohmura M, Nakamura T, Tokumoto Y, Tsugawa H, Handa H, Kobayashi T, Suematsu M. Cystathionine β-synthase and PGRMC1 as CO sensors. Free Radic Biol Med 2016; 99:333-344. [PMID: 27565814 DOI: 10.1016/j.freeradbiomed.2016.08.025] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 08/21/2016] [Accepted: 08/23/2016] [Indexed: 11/30/2022]
Abstract
Heme oxygenase (HO) is a mono-oxygenase utilizing heme and molecular oxygen (O2) as substrates to generate biliverdin-IXα and carbon monoxide (CO). HO-1 is inducible under stress conditions, while HO-2 is constitutive. A balance between heme and CO was shown to regulate cell death and survival in many experimental models. However, direct molecular targets to which CO binds to regulate cellular functions remained to be fully examined. We have revealed novel roles of CO-responsive proteins, cystathionine β-synthase (CBS) and progesterone receptor membrane component 1 (PGRMC1), in regulating cellular functions. CBS possesses a prosthetic heme that allows CO binding to inhibit the enzyme activity and to regulate H2S generation and/or protein arginine methylation. On the other hand, in response to heme accumulation in cells, PGRMC1 forms a stable dimer through stacking interactions of two protruding heme molecules. Heme-mediated PGRMC1 dimerization is necessary to interact with EGF receptor and cytochromes P450 that determine cell proliferation and xenobiotic metabolism. Furthermore, CO interferes with PGRMC1 dimerization by dissociating the heme stacking, and thus results in modulation of cell responses. This article reviews the intriguing functions of these two proteins in response to inducible and constitutive levels of CO with their pathophysiological implications.
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Affiliation(s)
- Yasuaki Kabe
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan; Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Tokyo 160-8582, Japan
| | - Takehiro Yamamoto
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Mayumi Kajimura
- Department of Biology, Keio University School of Medicine, Yokohama 223-8521, Japan
| | - Yuki Sugiura
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Ikko Koike
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Mitsuyo Ohmura
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan; Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Tokyo 160-8582, Japan
| | - Takashi Nakamura
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan
| | - Yasuhito Tokumoto
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan; Admission Center, Saitama Medical University, Moroyama 350-0495, Japan
| | - Hitoshi Tsugawa
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan; Japan Agency for Medical Research and Development, Core Research for Evolutional Science and Technology (AMED-CREST), Tokyo 160-8582, Japan
| | - Hiroshi Handa
- Department of Nanoparticle Translational Research, Tokyo Medical University, Tokyo 160-8402, Japan
| | - Takuya Kobayashi
- Department of Medical Chemistry and Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Makoto Suematsu
- Department of Biochemistry, Keio University School of Medicine, Tokyo 160-8582, Japan.
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12
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Suematsu M, Nakamura T, Tokumoto Y, Yamamoto T, Kajimura M, Kabe Y. CO-CBS-H2S Axis: From Vascular Mediator to Cancer Regulator. Microcirculation 2016; 23:183-90. [DOI: 10.1111/micc.12253] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 10/29/2015] [Indexed: 11/29/2022]
Affiliation(s)
- Makoto Suematsu
- Department of Biochemistry; Keio University School of Medicine; Japan Science and Technology Agency; ERATO Suematsu Gas Biology Project; Tokyo Japan
| | - Takashi Nakamura
- Department of Biochemistry; Keio University School of Medicine; Japan Science and Technology Agency; ERATO Suematsu Gas Biology Project; Tokyo Japan
| | - Yasuhito Tokumoto
- Department of Biochemistry; Keio University School of Medicine; Japan Science and Technology Agency; ERATO Suematsu Gas Biology Project; Tokyo Japan
| | - Takehiro Yamamoto
- Department of Biochemistry; Keio University School of Medicine; Japan Science and Technology Agency; ERATO Suematsu Gas Biology Project; Tokyo Japan
| | - Mayumi Kajimura
- Department of Biochemistry; Keio University School of Medicine; Japan Science and Technology Agency; ERATO Suematsu Gas Biology Project; Tokyo Japan
| | - Yasuaki Kabe
- Department of Biochemistry; Keio University School of Medicine; Japan Science and Technology Agency; ERATO Suematsu Gas Biology Project; Tokyo Japan
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13
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Huang CW, Moore PK. H2S Synthesizing Enzymes: Biochemistry and Molecular Aspects. Handb Exp Pharmacol 2015; 230:3-25. [PMID: 26162827 DOI: 10.1007/978-3-319-18144-8_1] [Citation(s) in RCA: 76] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Hydrogen sulfide (H2S) is a biologically active gas that is synthesized naturally by three enzymes, cystathionine γ-lyase (CSE), cystathionine β-synthetase (CBS) and 3-mercaptopyruvate sulfurtransferase (3-MST). These enzymes are constitutively present in a wide array of biological cells and tissues and their expression can be induced by a number of disease states. It is becoming increasingly clear that H2S is an important mediator of a wide range of cell functions in health and in disease. This review therefore provides an overview of the biochemical and molecular regulation of H2S synthesizing enzymes both in physiological conditions and their modulation in disease states with particular focus on their regulation in asthma, atherosclerosis and diabetes. The importance of small molecule inhibitors in the study of molecular pathways, the current use of common H2S synthesizing enzyme inhibitors and the relevant characteristics of mice in which these enzymes have been genetically deleted will also be summarized. With a greater understanding of the molecular regulation of these enzymes in disease states, as well as the availability of novel small molecules with high specificity targeted towards H2S producing enzymes, the potential to regulate the biological functions of this intriguing gas H2S for therapeutic effect can perhaps be brought one step closer.
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Affiliation(s)
- Caleb Weihao Huang
- Neurobiology Group, Life Sciences Institute and Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
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14
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Pinilla JM, Ayala-Ramírez P, García-Robles R, Olaya-C M, Bermúdez M. Expression of cystathionine beta-synthase and histopathological observations in placentas of patients with Down syndrome. J Neonatal Perinatal Med 2015; 8:77-84. [PMID: 26410429 DOI: 10.3233/npm-15814092] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
UNLABELLED Down syndrome is the most frequent aneuploidy in live births, with an overall frequency of 1/600-700 births. The overexpression of cystathionine β-synthase is thought to participate in the presentation of some phenotypes observed in Down syndrome. OBJECTIVE The aim of this study was to compare the expression levels of cystathionine β-synthase and histopathological observations from placentas of infants with Down syndrome and healthy newborns. MATERIALS AND METHODS Six placentas of fetuses/infants with Down syndrome and sixteen placentas of healthy fetuses were studied. Cystathionine β-synthase mRNA and protein expression were performed by real-time PCR and immunohistochemistry, respectively. RESULTS We observed an increase in cystathionine β-synthase mRNA expression (p = 0.0465) and protein levels (p = 0.009) in placentas of fetus/infants with Down syndrome compared with controls. Significantly more circinate edges (p = 0.0007) and trophoblast inclusions (p = 0.0037) were observed in the group with Down syndrome compared with control group. CONCLUSION The results demonstrate overexpression of cystathionine β-synthase mRNA and protein in placentas of fetuses/infants with trisomy 21. Further histological abnormalities were found in placentas of patients with Down syndrome, suggesting an alteration in the development of placenta.
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Affiliation(s)
| | - P Ayala-Ramírez
- Institute in Human Genetics, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
| | - R García-Robles
- Nutrition, Genetics and Metabolism Research Institute, Universidad el Bosque, Bogotá D.C., Colombia
| | - M Olaya-C
- Hospital Universitario San Ignacio, Pontificia Universidad Javeriana, Bogota D.C., Colombia
| | - M Bermúdez
- Institute in Human Genetics, Pontificia Universidad Javeriana, Bogotá D.C., Colombia
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15
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Reduced methylation of PFKFB3 in cancer cells shunts glucose towards the pentose phosphate pathway. Nat Commun 2014; 5:3480. [PMID: 24633012 PMCID: PMC3959213 DOI: 10.1038/ncomms4480] [Citation(s) in RCA: 180] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2013] [Accepted: 02/20/2014] [Indexed: 12/28/2022] Open
Abstract
Haem oxygenase (HO)-1/carbon monoxide (CO) protects cancer cells from oxidative stress, but the gas-responsive signalling mechanisms remain unknown. Here we show using metabolomics that CO-sensitive methylation of PFKFB3, an enzyme producing fructose 2,6-bisphosphate (F-2,6-BP), serves as a switch to activate phosphofructokinase-1, a rate-limiting glycolytic enzyme. In human leukaemia U937 cells, PFKFB3 is asymmetrically di-methylated at R131 and R134 through modification by protein arginine methyltransferase 1. HO-1 induction or CO results in reduced methylation of PFKFB3 in varied cancer cells to suppress F-2,6-BP, shifting glucose utilization from glycolysis toward the pentose phosphate pathway. Loss of PFKFB3 methylation depends on the inhibitory effects of CO on haem-containing cystathionine β-synthase (CBS). CBS modulates remethylation metabolism, and increases NADPH to supply reduced glutathione, protecting cells from oxidative stress and anti-cancer reagents. Once the methylation of PFKFB3 is reduced, the protein undergoes polyubiquitination and is degraded in the proteasome. These results suggest that the CO/CBS-dependent regulation of PFKFB3 methylation determines directional glucose utilization to ensure resistance against oxidative stress for cancer cell survival. Haem oxygenase 1 produces carbon monoxide and this byproduct is known to alter cellular signalling. Here, the authors show that carbon monoxide alters the methylation of PFKFB3 in cancer cells resulting in deregulated cellular metabolism and the shunting of glucose into the pentose phosphate pathway.
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16
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Zhao Y, Wu S, Gao X, Zhang Z, Gong J, Zhan R, Wang X, Wang W, Qian L. Inhibition of cystathionine β-synthase is associated with glucocorticoids over-secretion in psychological stress-induced hyperhomocystinemia rat liver. Cell Stress Chaperones 2013; 18:631-41. [PMID: 23512717 PMCID: PMC3745252 DOI: 10.1007/s12192-013-0416-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Revised: 02/26/2013] [Accepted: 03/01/2013] [Indexed: 01/29/2023] Open
Abstract
Hyperhomocysteinemia (HHcy), a pathological condition characterized by an increase in plasma concentration of total homocysteine (Hcy), is recognized as a risk factor for several diseases. The transsulfuration pathway is the main metabolic fate of Hcy utilization, which requires the activity of cystathionine β-synthase (CBS). Our results showed the development of HHcy induced by psychological stress was mainly derived from a reduction of CBS activity in the liver, which was accompanied by a significant decrease in its mRNA level. It suggested that the hepatic CBS enzyme regulated by stress at the level of transcription would have a profound effect on circulating Hcy levels. The expression of Sp3, a negative factor for cbs transcription, obviously increased in hepatocytes nuclei of stressed rats, but Sp1 was not altered. It indicated that Sp3 was the key point of variations in cbs transcription caused by stress. Meanwhile, we detected that augmented plasma Hcy concentrations correlated with glucocordicoids (GCs) over-secretion in response to stress, and CBS mRNA levels were markedly lowered in GCs-treated rat hepatocytes. Further results found that glucocorticoids receptor (GR) expression in hepatocyte nuclei of stress rats and GR nuclear translocation ratio was increased, and the same results were proved by experiments in vitro, i.e., GR nuclear translocation and Sp3 expression was remarkably increased in GCs-treated hepatocytes. Moreover, results from ChIP suggested GCs enhanced the binding of GR to the regulatory region of the Sp3 promoter. These results indicated that GCs inhibit CBS transcription by up-regulating Sp3 in psychological stress-induced HHcy.
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Affiliation(s)
- Yun Zhao
- />Key laboratory of stress medicine, Institute of Basic Medical Sciences, Beijing, China
| | - Shuqing Wu
- />Key laboratory of stress medicine, Institute of Basic Medical Sciences, Beijing, China
| | - Xiujie Gao
- />Institute of Health and Environmental Medicine, Tianjin, China
| | - Zhiqing Zhang
- />Institute of Health and Environmental Medicine, Tianjin, China
| | - Jingbo Gong
- />Key laboratory of stress medicine, Institute of Basic Medical Sciences, Beijing, China
| | - Rui Zhan
- />Key laboratory of stress medicine, Institute of Basic Medical Sciences, Beijing, China
| | - Xinxing Wang
- />Key laboratory of stress medicine, Institute of Basic Medical Sciences, Beijing, China
| | - Weiming Wang
- />Beijing University of Chinese Medicine, Beijing, China
| | - Lingjia Qian
- />Key laboratory of stress medicine, Institute of Basic Medical Sciences, Beijing, China
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17
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Caldwell JT, Edwards H, Dombkowski AA, Buck SA, Matherly LH, Ge Y, Taub JW. Overexpression of GATA1 confers resistance to chemotherapy in acute megakaryocytic Leukemia. PLoS One 2013; 8:e68601. [PMID: 23874683 PMCID: PMC3707876 DOI: 10.1371/journal.pone.0068601] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2012] [Accepted: 05/31/2013] [Indexed: 12/29/2022] Open
Abstract
It has been previously shown that acute myeloid leukemia (AML) patients with higher levels of GATA1 expression have poorer outcomes. Furthermore, pediatric Down syndrome (DS) patients with acute megakaryocytic leukemia (AMKL), whose blast cells almost universally harbor somatic mutations in exon 2 of the transcription factor gene GATA1, demonstrate increased overall survival relative to non-DS pediatric patients, suggesting a potential role for GATA1 in chemotherapy response. In this study, we confirmed that amongst non-DS patients, GATA1 transcripts were significantly higher in AMKL blasts compared to blasts from other AML subgroups. Further, GATA1 transcript levels significantly correlated with transcript levels for the anti-apoptotic protein Bcl-xL in our patient cohort. ShRNA knockdown of GATA1 in the megakaryocytic cell line Meg-01 resulted in significantly increased cytarabine (ara-C) and daunorubicin anti-proliferative sensitivities and decreased Bcl-xL transcript and protein levels. Chromatin immunoprecipitation (ChIP) and reporter gene assays demonstrated that the Bcl-x gene (which transcribes the Bcl-xL transcripts) is a bona fide GATA1 target gene in AMKL cells. Treatment of the Meg-01 cells with the histone deacetylase inhibitor valproic acid resulted in down-regulation of both GATA1 and Bcl-xL and significantly enhanced ara-C sensitivity. Furthermore, additional GATA1 target genes were identified by oligonucleotide microarray and ChIP-on-Chip analyses. Our findings demonstrate a role for GATA1 in chemotherapy resistance in non-DS AMKL cells, and identified additional GATA1 target genes for future studies.
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MESH Headings
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Cells, Cultured
- Child
- Child, Preschool
- Drug Resistance, Neoplasm/drug effects
- Drug Resistance, Neoplasm/genetics
- GATA1 Transcription Factor/genetics
- Gene Expression Profiling
- Gene Expression Regulation, Leukemic/drug effects
- Gene Expression Regulation, Leukemic/physiology
- Humans
- Leukemia, Megakaryoblastic, Acute/drug therapy
- Leukemia, Megakaryoblastic, Acute/genetics
- Microarray Analysis
- Up-Regulation/drug effects
- Up-Regulation/genetics
- Valproic Acid/pharmacology
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Affiliation(s)
- John Timothy Caldwell
- MD/PhD Program, Wayne State University School of Medicine, Detroit, Michigan, United States of America
- Cancer Biology Program, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Holly Edwards
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan, United States of America
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Alan A. Dombkowski
- Division of Pharmacology and Toxicology, Children’s Hospital of Michigan, Detroit, Michigan, United States of America
- Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Steven A. Buck
- Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan, United States of America
- Division of Pediatric Hematology/Oncology, Children’s Hospital of Michigan, Detroit, Michigan, United States of America
| | - Larry H. Matherly
- Cancer Biology Program, Wayne State University School of Medicine, Detroit, Michigan, United States of America
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan, United States of America
- Department of Pharmacology, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Yubin Ge
- Department of Oncology, Wayne State University School of Medicine, Detroit, Michigan, United States of America
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan, United States of America
| | - Jeffrey W. Taub
- Molecular Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, Michigan, United States of America
- Department of Pediatrics, Wayne State University School of Medicine, Detroit, Michigan, United States of America
- Division of Pediatric Hematology/Oncology, Children’s Hospital of Michigan, Detroit, Michigan, United States of America
- * E-mail:
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Transcriptional regulation by post-transcriptional modification—Role of phosphorylation in Sp1 transcriptional activity. Gene 2012; 508:1-8. [DOI: 10.1016/j.gene.2012.07.022] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 05/22/2012] [Accepted: 07/16/2012] [Indexed: 01/05/2023]
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A unique role of GATA1s in Down syndrome acute megakaryocytic leukemia biology and therapy. PLoS One 2011; 6:e27486. [PMID: 22110660 PMCID: PMC3217966 DOI: 10.1371/journal.pone.0027486] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2011] [Accepted: 10/18/2011] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Acute megakaryocytic leukemia (AMkL) in Down syndrome (DS) children is uniformly associated with somatic GATA1 mutations, which result in the synthesis of a shorter protein (GATA1s) with altered transactivation activity compared to the wild-type GATA1. It is not fully established whether leukemogenesis and therapeutic responses in DS AMkL patients are due to loss of the wild-type GATA1 or due to a unique function of GATA1s. METHODOLOGY Stable clones of CMK cells with decreased GATA1s or Bcl-2 levels were generated by using GATA1- or BCL-2-specific lentivirus shRNAs. In vitro ara-C, daunorubicin, and VP-16 cytotoxicities of the shRNA stable clones were determined by using the Cell Titer-blue reagent. Apoptosis and cell cycle distribution were determined by flow cytometry analysis. Changes in gene transcript levels were determined by gene expression microarray and/or real-time RT-PCR. Changes in protein levels were measured by Western blotting. In vivo binding of GATA1s to IL1A promoter was determined by chromatin immunoprecipitation assays. RESULTS Lentivirus shRNA knockdown of the GATA1 gene in the DS AMkL cell line, CMK (harbors a mutated GATA1 gene and only expresses GATA1s), resulting in lower GATA1s protein levels, promoted cell differentiation towards the megakaryocytic lineage and repressed cell proliferation. Increased basal apoptosis and sensitivities to ara-C, daunorubicin, and VP-16 accompanied by down-regulated Bcl-2 were also detected in the CMK GATA1 shRNA knockdown clones. Essentially the same results were obtained when Bcl-2 was knocked down with lentivirus shRNA in CMK cells. Besides Bcl-2, down-regulation of GATA1s also resulted in altered expression of genes (e.g., IL1A, PF4, and TUBB1) related to cell death, proliferation, and differentiation. CONCLUSION Our results suggest that GATA1s may facilitate leukemogenesis and potentially impact therapeutic responses in DS AMkL by promoting proliferation and survival, and by repressing megakaryocytic lineage differentiation, potentially by regulating expression of Bcl-2 protein and other relevant genes.
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Zhang L, Yang G, Tang G, Wu L, Wang R. Rat pancreatic level of cystathionine γ-lyase is regulated by glucose level via specificity protein 1 (SP1) phosphorylation. Diabetologia 2011; 54:2615-25. [PMID: 21618058 DOI: 10.1007/s00125-011-2187-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Accepted: 04/19/2011] [Indexed: 01/24/2023]
Abstract
AIMS/HYPOTHESIS Cystathionine γ-lyase (CSE) catalyses the endogenous production of hydrogen sulphide (H(2)S) in pancreatic beta cells, and H(2)S has been shown to inhibit insulin release from these cells. As altered pancreatic H(2)S production modulated by glucose has been previously shown, we hypothesised that the Cse gene could be regulated by glucose level in insulin-secreting cells. METHODS The effects of glucose on CSE protein level and mRNA level were analysed in INS-1E cells. Glucose effect on Cse promoter activity was tested by constructing a proximal Cse promoter vector including specificity protein 1 (Sp1) consensus sequence. RESULTS High glucose (20 mmol/l) inhibited H(2)S production in INS-1E cells and freshly isolated rat pancreatic islets. Cse mRNA expression, CSE activity and protein abundance were also profoundly reduced by high glucose. The involvement of SP1 in basal and high-glucose-regulated CSE production was demonstrated. Sp1-knockdown abolished a large portion of CSE production at basal glucose. Phosphorylation of SP1 stimulated by high glucose was inhibited by p38 mitogen-activated protein kinase (MAPK) inhibitors SB203580 and SB202190. After blocking p38 MAPK phosphorylation, the inhibitive effects of high glucose on CSE protein production and promoter activity in INS-1E cells were also virtually abolished. CONCLUSIONS/INTERPRETATION Glucose stimulates the phosphorylation of SP1 via p38 MAPK activation, which leads to decreased Cse promoter activity and subsequent downregulation of Cse gene expression. Inhibited H(2)S production through glucose-mediated CSE activity and production alterations may be involved in the fine control of glucose-induced insulin secretion.
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Affiliation(s)
- L Zhang
- Department of Biology, Lakehead University, 955 Oliver Road, Thunder Bay, ON, Canada, P7B 5E1
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RUNX1 regulates phosphoinositide 3-kinase/AKT pathway: role in chemotherapy sensitivity in acute megakaryocytic leukemia. Blood 2009; 114:2744-52. [PMID: 19638627 DOI: 10.1182/blood-2008-09-179812] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
RUNX1 (AML1) encodes the core binding factor alpha subunit of a heterodimeric transcription factor complex which plays critical roles in normal hematopoiesis. Translocations or down-regulation of RUNX1 have been linked to favorable clinical outcomes in acute leukemias, suggesting that RUNX1 may also play critical roles in chemotherapy responses in acute leukemias; however, the molecular mechanisms remain unclear. The median level of RUNX1b transcripts in Down syndrome (DS) children with acute megakaryocytic leukemia (AMkL) were 4.4-fold (P < .001) lower than that in non-DS AMkL cases. Short hairpin RNA knockdown of RUNX1 in a non-DS AMkL cell line, Meg-01, resulted in significantly increased sensitivity to cytosine arabinoside, accompanied by significantly decreased expression of PIK3CD, which encodes the delta catalytic subunit of the survival kinase, phosphoinositide 3 (PI3)-kinase. Transcriptional regulation of PIK3CD by RUNX1 was further confirmed by chromatin immunoprecipitation and promoter reporter gene assays. Further, a PI3-kinase inhibitor, LY294002, and cytosine arabinoside synergized in antileukemia effects on Meg-01 and primary pediatric AMkL cells. Our results suggest that RUNX1 may play a critical role in chemotherapy response in AMkL by regulating the PI3-kinase/Akt pathway. Thus, the treatment of AMkL may be improved by integrating PI3-kinase or Akt inhibitors into the chemotherapy of this disease.
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Inaba H, Jenkins JJ, McCarville MB, Morrison RR, Howard SC, Pui CH, Ribeiro RC. Pulmonary alveolar proteinosis in pediatric leukemia. Pediatr Blood Cancer 2008; 51:66-70. [PMID: 18085671 DOI: 10.1002/pbc.21442] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
BACKGROUND Pulmonary alveolar proteinosis (PAP) is a rare disorder characterized by intra-alveolar accumulation of periodic acid-Schiff (PAS)-positive surfactant components. Leukemia is the cancer most often associated with PAP; prolonged neutropenia and reduction of alveolar macrophages by myeloablative chemotherapy or leukemic infiltration are implicated. Only isolated cases of PAP have been reported, and pediatric experience is limited. PROCEDURE We reviewed all pathology records (1962-2007) of St. Jude Children's Research Hospital to identify patients with PAP. RESULTS Five patients had PAP. As expected, all had leukemia and had profound neutropenia at onset of PAP. A diagnosis was made only after PAS staining of bronchoalveolar lavage (BAL), lung biopsy, or autopsy specimens. Two patients had Down syndrome, which is not known to be associated with PAP. The other three patients had undergone hematopoietic stem cell transplantation (HSCT). Two patients showed clinical improvement or histological disappearance of PAP after neutropenia resolved. CONCLUSIONS PAP should be considered in the differential diagnosis of severe respiratory symptoms in neutropenic patients with hematologic malignancy, especially those with Down syndrome, a history of HSCT, or active disease. PAP should be confirmed by PAS staining of a BAL or lung biopsy specimen.
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Affiliation(s)
- Hiroto Inaba
- Department of Oncology, St. Jude Children's Research Hospital, Memphis, Tennessee, USA.
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23
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Muntean AG, Ge Y, Taub JW, Crispino JD. Transcription factor GATA-1 and Down syndrome leukemogenesis. Leuk Lymphoma 2007; 47:986-97. [PMID: 16840187 DOI: 10.1080/10428190500485810] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Mutations in transcription factors constitute one means by which normal hematopoietic progenitors are converted to leukemic stem cells. Recently, acquired mutations in the megakaryocytic regulator GATA1 have been found in essentially all cases of acute megakaryoblastic leukemia (AMkL) in children with Down syndrome and in the closely related malignancy transient myeloproliferative disorder. In all cases, mutations in GATA1 lead to the expression of a shorter isoform of GATA-1, named GATA-1s. Because GATA-1s retains both DNA binding zinc fingers, but is missing the N-terminal transactivation domain, it has been predicted that the inability of GATA-1s to regulate its normal class of megakaryocytic target genes is the mechanism by which mutations in GATA1 contribute to the disease. Indeed, several recent reports have confirmed that GATA-1s fails to properly regulate the growth of megakaryocytic precursors, likely through aberrant transcriptional regulation. Although the specific target genes of GATA-1 mis-regulated by GATA-1s that drive this abnormal growth remain undefined, multiple candidate genes have been identified via gene array studies. Finally, the inability of GATA-1s to promote expression of important metabolic genes, such as cytadine deaminase, likely contributes to the remarkable hypersensitivity of AMkL blasts to cytosine arabinoside. Future studies to define the entire class of genes dysregulated by mutations in GATA1 will provide important insights into the etiology of these malignancies.
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Affiliation(s)
- Andrew G Muntean
- Ben May Institute for Cancer Research, University of Chicago, IL 60637, USA
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24
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Udayakumar AM, Pathare AV, Muralitharan S, Alghzaly AA, Alkindi S, Raeburn JA. Trisomy 21 as a sole acquired abnormality in an adult Omani patient with CD7- and CD9-positive acute myeloid leukemia. Arch Med Res 2007; 38:797-802. [PMID: 17845902 DOI: 10.1016/j.arcmed.2007.04.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Accepted: 04/09/2007] [Indexed: 10/23/2022]
Abstract
We describe a case of acute myeloid leukemia (AML) in which trisomy 21 was the sole acquired cytogenetic abnormality. The immunophenotype showed positivity for CD7 and CD9 along with CD13, CD33, and CD34. The chromosomal analysis of bone marrow showed 47,XY +21 in all the metaphases analyzed. The constitutional karyotype was normal. The patient was an adult and did not have any features of Down's syndrome. The bone marrow morphology was AML-M2 as per the French-American-British (FAB) criteria. A final diagnosis of CD7- and CD9-positive AML-M2 was established with trisomy 21 as a sole cytogenetic abnormality. The patient responded remarkably well to chemotherapy and achieved complete clinical remission. This is the first case of CD7- and CD9-positive AML with trisomy 21 as a sole abnormality. A putative role for the co-expression of abnormal lymphoid markers in achieving quick remission is discussed.
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MESH Headings
- Adult
- Antigens, CD
- Antigens, CD7
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Bone Marrow/pathology
- Cytarabine/administration & dosage
- Cytogenetic Analysis
- Daunorubicin/administration & dosage
- Down Syndrome/complications
- Down Syndrome/diagnosis
- Down Syndrome/genetics
- Humans
- Karyotyping
- Leukemia, Myeloid, Acute/complications
- Leukemia, Myeloid, Acute/diagnosis
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/genetics
- Male
- Membrane Glycoproteins
- Remission Induction
- Tetraspanin 29
- Treatment Outcome
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Affiliation(s)
- Achandira M Udayakumar
- Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Sultanate of Oman.
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25
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Wu DYC, Wu R, Chen Y, Tarasova N, Chang MMJ. PMA stimulates MUC5B gene expression through an Sp1-based mechanism in airway epithelial cells. Am J Respir Cell Mol Biol 2007; 37:589-97. [PMID: 17600309 PMCID: PMC2048678 DOI: 10.1165/rcmb.2007-0145oc] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
We previously showed that the MUC5B gene expression was elevated by phorbol 12-myristate 13-acetate (PMA) through an epidermal growth factor receptor-independent Ras/MEKK1/JNK and P38 signaling-based transcriptional mechanism. In the current study, we elucidated the molecular basis of this transcriptional regulation using promoter-reporter gene expression and chromatin immunoprecipitation (ChIP) assays with primary human bronchial epithelial cells that are cultured at the air-liquid interface. We have observed that PMA-induced MUC5B promoter activity is blocked by the Sp1-binding inhibitor, mithramycin A, in a dose-dependent manner. Deletion analysis with the MUC5B promoter construct demonstrated that both basal and PMA-induced promoter-reporter activities reside within the -222/-78 bp region relative to the transcriptional start site. NoShift transcriptional factor assays demonstrated that PMA stimulated Sp1 binding, but not STAT1 and c-Myc binding. Immunoprecipitation studies also verified the enhanced phosphorylation of Sp1 after PMA treatment. Site-directed mutagenesis and transfection studies demonstrated the involvement of Sp1-1 (-122/-114) and the Sp1-2 (-197/-186) cis elements in the basal and PMA-induced MUC5B promoter activity. The ChIP assay with anti-RNA polymerase II reconfirmed the PMA-induced MUC5B promoter activity by showing enhanced RNA polymerase II-DNA complex containing putative MUC5B Sp1-1, Sp1-2, or Sp1-3 sites. However, the ChIP assay using anti-Sp1 antibody demonstrated that the PMA-stimulated binding is only at Sp1-2. These results suggested an Sp1-based transcriptional mechanism with Sp1-1 as the regulator of basal MUC5B promoter activity and Sp1-2 as the regulator of PMA-induced MUC5B gene expression in the human airway epithelial cells.
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Affiliation(s)
- Daphne Y C Wu
- Center for Comparative Respiratory Biology and Medicine, University of California at Davis, Davis, California 95616, USA
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26
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Ito A, Koshikawa N, Mochizuki S, Omura K, Takenaga K. Hypoxia-inducible factor-1 mediates the expression of DNA polymerase iota in human tumor cells. Biochem Biophys Res Commun 2006; 351:306-11. [PMID: 17056006 DOI: 10.1016/j.bbrc.2006.10.048] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2006] [Accepted: 10/10/2006] [Indexed: 11/16/2022]
Abstract
Hypoxia generated in tumors has been shown to contribute to mutations and genetic instability. However, the molecular mechanisms remain incompletely defined. Since reactive oxygen species (ROS) are overproduced immediately after reoxygenation of hypoxic cells and generate oxidized guanine, we assumed that the mechanisms might involve translesion DNA polymerases that can bypass oxidized guanine. We report here that hypoxia as well as hypoxia mimetics, desferrioxamine, and CoCl(2), enhanced the expression of DNA polymerase iota (pol iota) in human tumor cell lines. Searching the consensus sequence of hypoxia response element to which HIF-1 binds revealed that it locates in the intron 1 of the pol iota gene. These results suggest that HIF-1-mediated pol iota gene expression may be involved in the generation of translesion mutations during DNA replication after hypoxia followed by reoxygenation, thereby contributing to the accumulation of genetic changes in tumor cells.
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Affiliation(s)
- Akiko Ito
- Division of Chemotherapy, Chiba Cancer Center Research Institute, 666-2 Nitona, Chuoh-ku, Chiba 260-8717, Japan
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27
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Whalen R, Liu X, Boyer TD. Identification of a short form of ubiquitin-specific protease 3 that is a repressor of rat glutathione S-transferase gene expression. Biochem J 2006; 394:519-26. [PMID: 16279867 PMCID: PMC1408683 DOI: 10.1042/bj20051392] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The transcription rate and protein expression from both GSTA2 (glutathione S-transferase A2) and albumin genes decrease in rat liver after IL-6 (interleukin 6) plus DEX (dexamethasone) treatment of primary hepatocytes or after LPS (lipopolysaccharide)-induced acute-phase response in animals. The down-regulation is associated with the induced expression of a nuclear protein (termed IL6DEX-NP for IL-6/DEX-induced nuclear protein) that binds to a specific site on the promoter of GSTA2, leading to a decrease in transcriptional activity. IL6DEX-NP is not similar to other transcription factors, and, for identification, we functionally cloned it from a rat liver library using a yeast one-hybrid screen based on DNA-binding activity. The cloned sequence was a truncated form of USP3 (ubiquitin-specific protease 3) and the truncated USP3 protein in a yeast extract bound to DNA containing the IL6DEX-NP recognition sequence. Using 5'- and 3'-RACE (rapid amplification of cDNA ends), the complete sequence of USP3 was found in liver from LPS-treated rats. However, using Western blot analysis, only truncated forms of USP3 could be identified in nuclear extracts from LPS-treated rat livers. A GSTA2 promoter-reporter gene plasmid and USP3-expressing plasmids were transfected into rat hepatoma cells. Expression of the short form of USP3, but not the full-length protein, abolished expression from the reporter gene. Chromatin immunoprecipitation localized USP3 to the GSTA2 promoter in rat hepatocytes in vivo. We believe that the short form of USP3 is IL6DEX-NP and that it may play an important role in the negative regulation of proteins during the acute-phase response.
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Affiliation(s)
- Richard Whalen
- The University of Arizona Liver Research Institute, College of Medicine, University of Arizona, Tucson, AZ 85724-5136, USA.
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28
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Yang LV, Wan J, Ge Y, Fu Z, Kim SY, Fujiwara Y, Taub JW, Matherly LH, Eliason J, Li L. The GATA site-dependent hemogen promoter is transcriptionally regulated by GATA1 in hematopoietic and leukemia cells. Leukemia 2006; 20:417-25. [PMID: 16437149 DOI: 10.1038/sj.leu.2404105] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Hemgn (a gene symbol for hemogen in mouse, EDAG in human and RP59 in rat) encodes a nuclear protein that is highly expressed in hematopoietic tissues and acute leukemia. To characterize its regulatory mechanisms, we examined the activities of a Hemgn promoter containing 2975 bp of 5' flanking sequence and 196 bp of 5' untranslated region (5' UTR) sequence both in vitro and in vivo: this promoter is preferentially activated in a hematopoietic cell line, not in nonhematopoietic cell lines, and is sufficient to drive the transcription of a lacZ transgene in hematopoietic tissues in transgenic mice. Mutagenesis analyses showed that the 5' UTR including two highly conserved GATA boxes is critical for the promoter activity. GATA1, not GATA2, binds to the GATA binding sites and transactivates the Hemgn promoter in a dose-dependent manner. Furthermore, the expression of human hemogen (EDAG) transcripts were closely correlated with levels of GATA1 transcripts in primary acute myeloid leukemia specimens. This study suggests that the Hemgn promoter contains critical regulatory elements for its transcription in hematopoietic tissues and Hemgn is a direct target of GATA1 in leukemia cells.
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Affiliation(s)
- L V Yang
- Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, MI, USA
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29
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Ge Y, Dombkowski AA, LaFiura KM, Tatman D, Yedidi RS, Stout ML, Buck SA, Massey G, Becton DL, Weinstein HJ, Ravindranath Y, Matherly LH, Taub JW. Differential gene expression, GATA1 target genes, and the chemotherapy sensitivity of Down syndrome megakaryocytic leukemia. Blood 2005; 107:1570-81. [PMID: 16249385 PMCID: PMC1895418 DOI: 10.1182/blood-2005-06-2219] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Children with Down syndrome (DS) with acute megakaryocytic leukemia (AMkL) have very high survival rates compared with non-DS AMkL patients. Somatic mutations identified in the X-linked transcription factor gene, GATA1, in essentially all DS AMkL cases result in the synthesis of a shorter (40 kDa) protein (GATA1s) with altered transactivation activity and may lead to altered expression of GATA1 target genes. Using the Affymetrix U133A microarray chip, we identified 551 differentially expressed genes between DS and non-DS AMkL samples. Transcripts for the bone marrow stromal-cell antigen 2 (BST2) gene, encoding a transmembrane glycoprotein potentially involved in interactions between leukemia cells and bone marrow stromal cells, were 7.3-fold higher (validated by real-time polymerase chain reaction) in the non-DS compared with the DS group. Additional studies confirmed GATA1 protein binding and transactivation of the BST2 promoter; however, stimulation of BST2 promoter activity by GATA1s was substantially reduced compared with the full-length GATA1. CMK sublines, transfected with the BST2 cDNA and incubated with HS-5 bone marrow stromal cells, exhibited up to 1.7-fold reduced cytosine arabinoside (ara-C)-induced apoptosis, compared with mock-transfected cells. Our results demonstrate that genes that account for differences in survival between DS and non-DS AMkL cases may be identified by microarray analysis and that differential gene expression may reflect relative transactivation capacities of the GATA1s and full-length GATA1 proteins.
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Affiliation(s)
- Yubin Ge
- Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute of Environmental Sciences, Wayne State University, Detroit, MI 48201, USA
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30
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Liu M, Whetstine J, Payton S, Ge Y, Flatley R, Matherly L. Roles of USF, Ikaros and Sp proteins in the transcriptional regulation of the human reduced folate carrier B promoter. Biochem J 2005; 383:249-57. [PMID: 15214842 PMCID: PMC1134065 DOI: 10.1042/bj20040414] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The hRFC (human reduced folate carrier) is ubiquitously but differentially expressed in human tissues and its levels are regulated by up to seven non-coding regions (A1, A2, A, B, C, D and E) and at least four promoters. For the hRFC-B basal promoter, regulation involves binding of Sp (specificity protein) transcription factors to a critical GC-box. By transiently transfecting HT1080 cells with 5'- and 3'-deletion constructs spanning 1057 bp of upstream sequence, a transcriptionally important region was localized to 158 bp flanking the transcriptional start sites. By gel shift and chromatin immunoprecipitation assays, USF (upstream stimulatory factor), Sp1 and Ikaros-related proteins were bound to consensus elements (one E-box, two GC-box and three Ikaros) within this region. The functional importance of these elements was confirmed by transient tranfections of HT1080 cells with hRFC-B reporter constructs in which they were mutated, and by co-transfections of Drosophila Mel-2 cells with wild-type hRFC-B promoter and expression constructs for USF1, USF2a, Sp1 and Ikaros 2 and 8. Both USF1 and Sp1 proteins transactivated the hRFC-B promoter. Sp1 combined with USF1 resulted in a synergistic transactivation. Identical results were obtained with USF2a. Ikaros 2 was a repressor of hRFC-B promoter activity whose effects were partly reversed by the dominant-negative Ikaros 8. In HT1080 cells, transfection with Ikaros 2 decreased endogenous hRFC-B transcripts, whereas USF1 and Sp1 increased transcript levels. Ikaros 2 also decreased reporter gene activity and levels of acetylated chromatin associated with the endogenous promoter. Collectively, these results identify transcriptionally important regions in the hRFC-B promoter that include multiple GC-box, Ikaros and E-box elements. Our results also suggest that co-operative interactions between transcription factors Sp1 and USF are essential for high-level hRFC-B transactivation and imply that these effects are modulated by the family of Ikaros proteins and by histone acetylation.
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Affiliation(s)
- Mingjun Liu
- *Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 E. Warren Ave., Detroit, MI 48201, U.S.A
| | - Johnathan R. Whetstine
- †Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI, U.S.A
| | - Scott G. Payton
- †Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI, U.S.A
| | - Yubin Ge
- *Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 E. Warren Ave., Detroit, MI 48201, U.S.A
| | - Robin M. Flatley
- *Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 E. Warren Ave., Detroit, MI 48201, U.S.A
| | - Larry H. Matherly
- *Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, 110 E. Warren Ave., Detroit, MI 48201, U.S.A
- †Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI, U.S.A
- To whom correspondence should be addressed, at the Barbara Ann Karmanos Cancer Institute, Detroit, MI, U.S.A. (email )
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31
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Abstract
It has been recognized that chromosomal abnormalities in childhood leukemia, are linked to both leukemogenesis and segregate patients into prognostic treatment groups. This is best exemplified in cases of children with Down syndrome (DS), who have significantly higher risks of developing leukemia compared to non-DS children and distinctive treatment outcomes, particularly in cases of acute myeloid leukemia (AML). The high event-free survival (EFS) rates of DS AML patients and in particular, patients with megakaryocytic leukemia (AMkL), at least in part reflects an increased sensitivity to cytosine arabinoside (ara-C) secondary to increased expression of the chromosome 21-localized gene, cystathionine-beta-synthase, and potentially global mechanisms which increase the susceptibility of cells to undergo apoptosis. Somatic mutations of the X-linked transcription factor gene, GATA1, have been detected uniformly and exclusively in DS AMkL cases, which may lead to altered expression of GATA1 target genes and alter the metabolism of drugs including ara-C. Hyperdiploid acute lymphoblastic leukemia (ALL) cells with extra copies of chromosome 21, generate higher levels of the active methotrexate (MTX) metabolite, MTX polyglutamates. This is on account of increased intracellular transport of MTX via the reduced folate carrier (RFC) whose gene is localized to chromosome 21 and may also account for the increased MTX-associated toxicity of DS ALL patients. Microarray technology should lead to the identification of additional gene targets linked to the treatment response of specific cytogenetic leukemia subgroups.
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MESH Headings
- Acute Disease
- Antineoplastic Agents, Alkylating/adverse effects
- Antineoplastic Agents, Alkylating/metabolism
- Antineoplastic Agents, Alkylating/therapeutic use
- Antineoplastic Combined Chemotherapy Protocols/adverse effects
- Antineoplastic Combined Chemotherapy Protocols/metabolism
- Antineoplastic Combined Chemotherapy Protocols/therapeutic use
- Child
- Chromosomes, Human, Pair 21
- Disease-Free Survival
- Down Syndrome/complications
- Down Syndrome/physiopathology
- Humans
- Leukemia, Megakaryoblastic, Acute/drug therapy
- Leukemia, Megakaryoblastic, Acute/genetics
- Leukemia, Myeloid/drug therapy
- Leukemia, Myeloid/genetics
- Methotrexate/adverse effects
- Methotrexate/metabolism
- Methotrexate/therapeutic use
- Prognosis
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Affiliation(s)
- Jeffrey W Taub
- Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan, USA.
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32
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Payton SG, Whetstine JR, Ge Y, Matherly LH. Transcriptional regulation of the human reduced folate carrier promoter C: synergistic transactivation by Sp1 and C/EBP beta and identification of a downstream repressor. ACTA ACUST UNITED AC 2004; 1727:45-57. [PMID: 15652157 DOI: 10.1016/j.bbaexp.2004.11.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Revised: 11/11/2004] [Accepted: 11/17/2004] [Indexed: 11/21/2022]
Abstract
The human reduced folate carrier (hRFC) is ubiquitously but differentially expressed in human tissues and its levels are regulated by up to six alternatively spliced non-coding regions (designated A1/A2, A, B, C, D, and E) and by at least four promoters. By transient transfections of HepG2 human hepatoma cells with 5' and 3' deletion constructs spanning 2883 bp of upstream sequence, a transcriptionally important region was localized to within 177 bp flanking the transcriptional start sites for exon C. By gel shift and chromatin immunoprecipitation assays, Sp1 and C/EBP beta transcription factors were found to bind consensus elements (GC-box, CCAAT-box) within this region. The functional importance of these elements was confirmed by transient tranfections of HepG2 cells with hRFC-C reporter constructs in which these elements were mutated, and by co-transfections of Drosophila SL-2 cells with wild-type hRFC-C promoter and expression constructs for Sp1 and C/EBP beta. Whereas both Sp1 and C/EBP beta transactivated hRFC-C promoter activity, C/EBP alpha and gamma were transcriptionally inert. Sp1 combined with C/EBP beta resulted in a synergistic transactivation. In HepG2 cells, transfections with Sp1 and C/EBP beta both increased endogenous levels of hRFC-C transcripts. By 3' deletion analysis, a repressor sequence was localized to within 71 bp flanking the minimal promoter. On gel shifts, a novel transcriptional repressor was localized to within 30 bp. Collectively, these results identify transcriptionally important regions in the hRFC-C minimal promoter that include a GC-box and CCAAT-box, and suggest that cooperative interactions between Sp1 and C/EBP beta are essential for hRFC-C transactivation. Another possible factor in the tissue-specific regulation of the hRFC-C region involves the downstream repressor flanking the minimal promoter.
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Affiliation(s)
- Scott G Payton
- Department of Pharmacology, Wayne State University, School of Medicine, Detroit, MI, USA
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33
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Abstract
The Sp family of transcription factors is united by a particular combination of three conserved Cys2His2 zinc fingers that form the sequence-specific DNA-binding domain. Within the Sp family of transcription factors, Sp1 and Sp3 are ubiquitously expressed in mammalian cells. They can bind and act through GC boxes to regulate gene expression of multiple target genes. Although Sp1 and Sp3 have similar structures and high homology in their DNA binding domains, in vitro and in vivo studies reveal that these transcription factors have strikingly different functions. Sp1 and Sp3 are able to enhance or repress promoter activity. Regulation of the transcriptional activity of Sp1 and Sp3 occurs largely at the post-translational level. In this review, we focus on the roles of Sp1 and Sp3 in the regulation of gene expression.Key words: Sp1, Sp3, gene regulation, sub-cellular localization.
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Affiliation(s)
- Lin Li
- Manitoba Institute of Cell Biology, University of Manitoba, Winnipeg, Canada
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34
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Ge Y, Jensen TL, Stout ML, Flatley RM, Grohar PJ, Ravindranath Y, Matherly LH, Taub JW. The role of cytidine deaminase and GATA1 mutations in the increased cytosine arabinoside sensitivity of Down syndrome myeloblasts and leukemia cell lines. Cancer Res 2004; 64:728-35. [PMID: 14744791 DOI: 10.1158/0008-5472.can-03-2456] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Myeloblasts from Down syndrome (DS) children with acute myeloid leukemia (AML) are significantly more sensitive in vitro to 1-beta-D-arabinofuranosylcytosine (ara-C) and generate higher 1-beta-D-arabinofuranosylcytosine 5'-triphosphate (ara-CTP) than non-DS AML myeloblasts. Semiquantitative reverse transcription-PCR analyses demonstrated that transcripts for cytidine deaminase (CDA) were 2.7-fold lower in DS than for non-DS myeloblasts. In contrast, transcripts of cystathionine-beta-synthase and deoxycytidine kinase were a median 12.5- and 2.6-fold higher in DS compared with non-DS myeloblasts. The ratio of deoxycytidine kinase/CDA transcripts significantly correlated with ara-C sensitivities and ara-CTP generation. In clinically relevant AML cell line models, high cystathionine-beta-synthase transcripts in DS CMK cells were accompanied by 10-fold greater ara-C sensitivity and 2.4-fold higher levels of ara-CTP compared with non-DS CMS cells. Overexpression of CDA in non-DS THP-1 cells was associated with a 100-fold decreased ara-C sensitivity and 40-fold decreased ara-CTP generation. THP-1 cells secreted CDA into the incubation media and converted extracellular ara-C completely to 1-beta-D-arabinofuranosyluracil within 30 min. Rapid amplification of 5'-cDNA ends (5'-RACE) and reverse transcription-PCR assays identified short- (sf) and long-form (lf) CDA transcripts in THP-1 cells with different 5' untranslated regions and translational start sites; however, only the latter resulted in the active CDA. Although 5' flanking sequences for both CDA transcripts exhibited promoter activity in reporter gene assays, activity for the CDAlf was low. The presence of several GATA1 binding sites in the CDAsf promoter and the uniform detection of GATA1 mutations in DS megakaryocytic leukemia suggested the potential role of GATA1 in regulating CDA transcription and the CDAsf promoter acting as an enhancer. Transfection of GATA1 into Drosophila Mel-2 cells stimulated the CDAlf promoter in a dose-dependent fashion. Additional identification of the mechanisms of differential expression of genes encoding enzymes involved in ara-C metabolism between DS and non-DS myeloblasts may lead to improvements in AML therapy.
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Affiliation(s)
- Yubin Ge
- Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Division of Pediatric Hematology/Oncology, Children's Hospital of Michigan, Detroit, Michigan, USA
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Abstract
Abstract
Major strides have been made in our understanding of the molecular basis of adult and pediatric leukemias. More than one hundred disease alleles have been identified and characterized in cell culture and murine models of leukemia. In some instances, molecularly targeted therapies have been developed based on these insights that are currently in clinical trials, such as small molecule inhibitors of FLT3. In addition, it has recently been appreciated that, as with normal hematopoiesis, there is a hierarchical organization among leukemic cells that includes a rare population of leukemic stem cells that have properties of self-renewal. Understanding the characteristics of these leukemic stem cells may provide new insights into leukemia therapies that target self-renewal pathways.
In Section I, Dr. Craig Jordan reviews the data that supports the existence of a “leukemia stem cell.” He provides an overview of the functional properties of leukemic stem cells, their relationship to hematopoietic stem cells, and the relevance of leukemic stem cells in other human malignancies including solid tumors. He briefly discusses what is known of the pathways that regulate properties of self-renewal.
Dr. Gary Gilliland provides an overview of the genetics of adult leukemias in Section II and ongoing genome-wide strategies for discovery of new disease alleles. He describes the clinical and therapeutic implications of these findings and provides examples of bench-to-bedside translation of molecularly targeted therapies for AML, including the use of FLT3 inhibitors.
In Section III, Dr. Carolyn Felix reviews recent advances in our understanding of the genetics and therapy of pediatric leukemias. She provides an overview of leukemias that are common in pediatric malignancies but rarely observed in adults, including the TEL-AML1 (ETV6-RUNX1) fusion associated with pediatric B-cell ALL, the OTT-MAL fusion associated with infant megakaryoblastic leukemia, PTPN11 mutations in juvenile myelomonocytic leukemia, and MLL fusion genes in leukemogenesis, among others.
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Affiliation(s)
- D Gary Gilliland
- Brigham and Women's Hospital, Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA
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Maclean KN, Kraus E, Kraus JP. The dominant role of Sp1 in regulating the cystathionine beta-synthase -1a and -1b promoters facilitates potential tissue-specific regulation by Kruppel-like factors. J Biol Chem 2003; 279:8558-66. [PMID: 14670973 DOI: 10.1074/jbc.m310211200] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Cystathionine beta-synthase (CBS) catalyzes the condensation of serine with homocysteine to form cystathionine and occupies a crucial regulatory position between the methionine cycle and transsulfuration. The human cystathionine beta-synthase gene promoters -1a and -1b are expressed in a limited number of tissues and are coordinately regulated with proliferation through a redox-sensitive mechanism. Site-directed mutagenesis, DNase I footprinting and deletion analysis of 5276 bp of 5' proximal -1b flanking sequence revealed that this region does not confer tissue-specific expression and that 210 bp of proximal sequence is sufficient for maximal promoter activity. As little as 32 bp of the -1b proximal promoter region is capable of driving transcription in HepG2 cells, and this activity is entirely dependent upon the presence of a single overlapping Sp1/Egr1 binding site. Co-transfection studies in Drosophila SL2 cells indicated that both promoters are transactivated by Sp1 and Sp3 but only the -1b promoter is subject to a site-specific synergistic regulatory interaction between Sp1 and Sp3. Sp1-deficient fibroblasts expressing both Sp3 and NF-Y were negative for CBS activity. Transfection of these cells with a mammalian Sp1 expression construct induced high levels of CBS activity indicating that Sp1 has a critical and indispensable role in the regulation of cystathionine beta-synthase. Sp1 binding to both CBS promoters is sensitive to proliferation status and is negatively regulated by Kruppel-like factors in co-transfection experiments suggesting a possible mechanism for the tissue specific regulation of cystathionine beta-synthase.
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Affiliation(s)
- Kenneth N Maclean
- Department of Pediatrics, University of Colorado School of Medicine, Denver, Colorado 80262, USA.
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Ge Y, Jensen TL, Matherly LH, Taub JW. Physical and Functional Interactions between USF and Sp1 Proteins Regulate Human Deoxycytidine Kinase Promoter Activity. J Biol Chem 2003; 278:49901-10. [PMID: 14514691 DOI: 10.1074/jbc.m305085200] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Deoxycytidine kinase (EC 2.7.1.74, dCK) is central to drug activity of anticancer and antiviral agents such as cytosine arabinoside (araC) and gemcitabine. HepG2 hepatocellular carcinoma cells were used to study the transcriptional regulation of dCK. 5'-Deletion and site-directed mutagenesis of the dCK upstream region (positions -464 to -27) confirmed the importance of two GC-boxes (positions -317 to -309 and -213 to -206) and two E-boxes (positions -302 to -297 and -278 to -273). In vitro electromobility shift assays with HepG2 nuclear extracts and in vivo chromatin immunoprecipitation assays with HepG2 chromatin extracts confirmed the presence of bound Sp1/Sp3 and USF1/2. Co-transfections in HepG2 cells showed that USF1 and USF2a stimulated and Sp1 repressed promoter activity from a dCK-luciferase reporter gene construct. In Sp- and USF-null Drosophila Mel-2 cells, both Sp1 and USF1 stimulated dCK promoter activity in a dose-dependent manner, however, both Sp3 and USF2a were effectively inert. Combined Sp1 and USF1 showed additive transactivation at lower concentrations of Sp1. Sp1 was inhibitory at higher levels. Stimulation by combined USF1/USF2a with Sp1 was similar to that for USF1 alone with Sp1, whereas transactivation by Sp1 and USF2a without USF1 was synergistic. Physical interactions between USF and Sp proteins were confirmed by immunoprecipitations with Sp- and USF-specific antibodies. Domain mapping of USF1 and USF2a localized the functional interactions between USF and Sp proteins to the DNA binding domain of USF. Identifying the physical and functional interactions between Sp and USF proteins may lead to a better understanding of the basis for differential expression of the dCK gene in tumor cells and may foster strategies for up-regulating dCK gene expression and improving chemotherapy with araC and gemcitabine.
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Affiliation(s)
- Yubin Ge
- Experimental and Clinical Therapeutics Program, Barbara Ann Karmanos Cancer Institute, Detroit, Michigan 48201, USA
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Gurbuxani S, Vyas P, Crispino JD. Recent insights into the mechanisms of myeloid leukemogenesis in Down syndrome. Blood 2003; 103:399-406. [PMID: 14512321 DOI: 10.1182/blood-2003-05-1556] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
GATA-1 is the founding member of a transcription factor family that regulates growth and maturation of a diverse set of tissues. GATA-1 is expressed primarily in hematopoietic cells and is essential for proper development of erythroid cells, megakaryocytes, eosinophils, and mast cells. Although loss of GATA-1 leads to differentiation arrest and apoptosis of erythroid progenitors, absence of GATA-1 promotes accumulation of immature megakaryocytes. Recently, we and others have reported that mutagenesis of GATA1 is an early event in Down syndrome (DS) leukemogenesis. Acquired mutations in GATA1 were detected in the vast majority of patients with acute megakaryoblastic leukemia (DS-AMKL) and in nearly every patient with transient myeloproliferative disorder (TMD), a "preleukemia" that may be present in as many as 10% of infants with DS. Although the precise pathway by which mutagenesis of GATA1 contributes to leukemia is unknown, these findings confirm that GATA1 plays an important role in both normal and malignant hematopoiesis. Future studies to define the mechanism that results in the high frequency of GATA1 mutations in DS and the role of altered GATA1 in TMD and DS-AMKL will shed light on the multistep pathway in human leukemia and may lead to an increased understanding of why children with DS are markedly predisposed to leukemia.
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Affiliation(s)
- Sandeep Gurbuxani
- University of Chicago, 924 E 57th St, Rm R116, Chicago, IL 60637, USA
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