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Xie WQ, Yang X, Gu RX, Tian Z, Xing HY, Tang KJ, Rao Q, Qiu SW, Wang M, Wang JX. [Establishment of leukemia cell model with inducible AML1-ETO expression and its effect on fatty acid metabolism in leukemia cells]. ZHONGHUA XUE YE XUE ZA ZHI = ZHONGHUA XUEYEXUE ZAZHI 2023; 44:366-372. [PMID: 37550185 PMCID: PMC10440621 DOI: 10.3760/cma.j.issn.0253-2727.2023.05.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Received: 03/10/2023] [Indexed: 08/09/2023]
Abstract
Objective: To investigate the effect of the AML1-ETO (AE) fusion gene on the biological function of U937 leukemia cells by establishing a leukemia cell model that induces AE fusion gene expression. Methods: The doxycycline (Dox) -dependent expression of the AE fusion gene in the U937 cell line (U937-AE) were established using a lentivirus vector system. The Cell Counting Kit 8 methods, including the PI and sidanilide induction, were used to detect cell proliferation, cell cycle-induced differentiation assays, respectively. The effect of the AE fusion gene on the biological function of U937-AE cells was preliminarily explored using transcriptome sequencing and metabonomic sequencing. Results: ①The Dox-dependent Tet-on regulatory system was successfully constructed to regulate the stable AE fusion gene expression in U937-AE cells. ②Cell proliferation slowed down and the cell proliferation rate with AE expression (3.47±0.07) was lower than AE non-expression (3.86 ± 0.05) after inducing the AE fusion gene expression for 24 h (P<0.05). The proportion of cells in the G(0)/G(1) phase in the cell cycle increased, with AE expression [ (63.45±3.10) %) ] was higher than AE non-expression [ (41.36± 9.56) %] (P<0.05). The proportion of cells expressing CD13 and CD14 decreased with the expression of AE. The AE negative group is significantly higher than the AE positive group (P<0.05). ③The enrichment analysis of the transcriptome sequencing gene set revealed significantly enriched quiescence, nuclear factor kappa-light-chain-enhancer of activated B cells, interferon-α/γ, and other inflammatory response and immune regulation signals after AE expression. ④Disorder of fatty acid metabolism of U937-AE cells occurred under the influence of AE. The concentration of the medium and short-chain fatty acid acylcarnitine metabolites decreased in cells with AE expressing, propionyl L-carnitine, wherein those with AE expression (0.46±0.13) were lower than those with AE non-expression (1.00±0.27) (P<0.05). The metabolite concentration of some long-chain fatty acid acylcarnitine increased in cells with AE expressing tetradecanoyl carnitine, wherein those with AE expression (1.26±0.01) were higher than those with AE non-expression (1.00±0.05) (P<0.05) . Conclusion: This study successfully established a leukemia cell model that can induce AE expression. The AE expression blocked the cell cycle and inhibited cell differentiation. The gene sets related to the inflammatory reactions was significantly enriched in U937-AE cells that express AE, and fatty acid metabolism was disordered.
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Affiliation(s)
- W Q Xie
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - X Yang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - R X Gu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - Z Tian
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - H Y Xing
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - K J Tang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - Q Rao
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - S W Qiu
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - M Wang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
| | - J X Wang
- State Key Laboratory of Experimental Hematology, National Clinical Research Center for Blood Diseases, Haihe Laboratory of Cell Ecosystem, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China Tianjin Institutes of Health Science, Tianjin 301600, China
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Zhang YF, Wang XL, Xu CH, Liu N, Zhang L, Zhang YM, Xie YY, Zhang YL, Huang QH, Wang L, Chen Z, Chen SJ, Roeder RG, Shen S, Xue K, Sun XJ. A direct comparison between AML1-ETO and ETO2-GLIS2 leukemia fusion proteins reveals context-dependent binding and regulation of target genes and opposite functions in cell differentiation. Front Cell Dev Biol 2022; 10:992714. [PMID: 36158200 PMCID: PMC9490184 DOI: 10.3389/fcell.2022.992714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/12/2022] [Indexed: 11/13/2022] Open
Abstract
The ETO-family transcriptional corepressors, including ETO, ETO2, and MTGR1, are all involved in leukemia-causing chromosomal translocations. In every case, an ETO-family corepressor acquires a DNA-binding domain (DBD) to form a typical transcription factor—the DBD binds to DNA, while the ETO moiety manifests transcriptional activity. A directly comparative study of these “homologous” fusion transcription factors may clarify their similarities and differences in regulating transcription and leukemogenesis. Here, we performed a side-by-side comparison between AML1-ETO and ETO2-GLIS2, the most common fusion proteins in M2-and M7-subtypes of acute myeloid leukemia, respectively, by inducible expression of them in U937 leukemia cells. We found that, although AML1-ETO and ETO2-GLIS2 can use their own DBDs to bind DNA, they share a large proportion of genome-wide binding regions dependent on other cooperative transcription factors, including the ETS-, bZIP- and bHLH-family proteins. AML1-ETO acts as either transcriptional repressor or activator, whereas ETO2-GLIS2 mainly acts as activator. The repressor-versus-activator functions of AML1-ETO might be determined by the abundance of cooperative transcription factors/cofactors on the target genes. Importantly, AML1-ETO and ETO2-GLIS2 differentially regulate key transcription factors in myeloid differentiation including PU.1 and C/EBPβ. Consequently, AML1-ETO inhibits, but ETO2-GLIS2 facilitates, myeloid differentiation of U937 cells. This function of ETO2-GLIS2 is reminiscent of a similar effect of MLL-AF9 as previously reported. Taken together, this directly comparative study between AML1-ETO and ETO2-GLIS2 in the same cellular context provides insights into context-dependent transcription regulatory mechanisms that may underlie how these seemingly “homologous” fusion transcription factors exert distinct functions to drive different subtypes of leukemia.
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3
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Davis AG, Johnson DT, Zheng D, Wang R, Jayne ND, Liu M, Shin J, Wang L, Stoner SA, Zhou JH, Ball ED, Tian B, Zhang DE. Alternative polyadenylation dysregulation contributes to the differentiation block of acute myeloid leukemia. Blood 2022; 139:424-438. [PMID: 34482400 PMCID: PMC8777198 DOI: 10.1182/blood.2020005693] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Accepted: 08/16/2021] [Indexed: 01/22/2023] Open
Abstract
Posttranscriptional regulation has emerged as a driver for leukemia development and an avenue for therapeutic targeting. Among posttranscriptional processes, alternative polyadenylation (APA) is globally dysregulated across cancer types. However, limited studies have focused on the prevalence and role of APA in myeloid leukemia. Furthermore, it is poorly understood how altered poly(A) site usage of individual genes contributes to malignancy or whether targeting global APA patterns might alter oncogenic potential. In this study, we examined global APA dysregulation in patients with acute myeloid leukemia (AML) by performing 3' region extraction and deep sequencing (3'READS) on a subset of AML patient samples along with healthy hematopoietic stem and progenitor cells (HSPCs) and by analyzing publicly available data from a broad AML patient cohort. We show that patient cells exhibit global 3' untranslated region (UTR) shortening and coding sequence lengthening due to differences in poly(A) site (PAS) usage. Among APA regulators, expression of FIP1L1, one of the core cleavage and polyadenylation factors, correlated with the degree of APA dysregulation in our 3'READS data set. Targeting global APA by FIP1L1 knockdown reversed the global trends seen in patients. Importantly, FIP1L1 knockdown induced differentiation of t(8;21) cells by promoting 3'UTR lengthening and downregulation of the fusion oncoprotein AML1-ETO. In non-t(8;21) cells, FIP1L1 knockdown also promoted differentiation by attenuating mechanistic target of rapamycin complex 1 (mTORC1) signaling and reducing MYC protein levels. Our study provides mechanistic insights into the role of APA in AML pathogenesis and indicates that targeting global APA patterns can overcome the differentiation block in patients with AML.
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Affiliation(s)
- Amanda G Davis
- Moores Cancer Center and
- Division of Biological Sciences, University of California San Diego, La Jolla, CA
| | - Daniel T Johnson
- Moores Cancer Center and
- Division of Biological Sciences, University of California San Diego, La Jolla, CA
| | - Dinghai Zheng
- Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ
| | - Ruijia Wang
- Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ
| | - Nathan D Jayne
- Moores Cancer Center and
- Division of Biological Sciences, University of California San Diego, La Jolla, CA
| | - Mengdan Liu
- Moores Cancer Center and
- Division of Biological Sciences, University of California San Diego, La Jolla, CA
| | - Jihae Shin
- Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ
| | - Luyang Wang
- Program in Gene Expression and Regulation, Center for Systems and Computational Biology, The Wistar Institute, Philadelphia, PA
| | | | - Jie-Hua Zhou
- Division of Blood and Marrow Transplantation, Department of Medicine; and
| | - Edward D Ball
- Division of Blood and Marrow Transplantation, Department of Medicine; and
| | - Bin Tian
- Department of Microbiology, Biochemistry, and Molecular Genetics, Rutgers New Jersey Medical School, Newark, NJ
- Program in Gene Expression and Regulation, Center for Systems and Computational Biology, The Wistar Institute, Philadelphia, PA
| | - Dong-Er Zhang
- Moores Cancer Center and
- Division of Biological Sciences, University of California San Diego, La Jolla, CA
- Department of Pathology, University of California San Diego, La Jolla, CA
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4
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Nafria M, Keane P, Ng ES, Stanley EG, Elefanty AG, Bonifer C. Expression of RUNX1-ETO Rapidly Alters the Chromatin Landscape and Growth of Early Human Myeloid Precursor Cells. Cell Rep 2021; 31:107691. [PMID: 32460028 PMCID: PMC7262600 DOI: 10.1016/j.celrep.2020.107691] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 03/12/2020] [Accepted: 05/05/2020] [Indexed: 01/03/2023] Open
Abstract
Acute myeloid leukemia (AML) is a hematopoietic malignancy caused by recurrent mutations in genes encoding transcriptional, chromatin, and/or signaling regulators. The t(8;21) translocation generates the aberrant transcription factor RUNX1-ETO (RUNX1-RUNX1T1), which by itself is insufficient to cause disease. t(8;21) AML patients show extensive chromatin reprogramming and have acquired additional mutations. Therefore, the genomic and developmental effects directly and solely attributable to RUNX1-ETO expression are unclear. To address this, we employ a human embryonic stem cell differentiation system capable of forming definitive myeloid progenitor cells to express RUNX1-ETO in an inducible fashion. Induction of RUNX1-ETO causes extensive chromatin reprogramming by interfering with RUNX1 binding, blocks differentiation, and arrests cellular growth, whereby growth arrest is reversible following RUNX1-ETO removal. Single-cell gene expression analyses show that RUNX1-ETO induction alters the differentiation of early myeloid progenitors, but not of other progenitor types, indicating that oncoprotein-mediated transcriptional reprogramming is highly target cell specific. RUNX1-ETO reversibly arrests the growth of human ESC-derived early myeloid cells RUNX1-ETO disrupts global RUNX1 binding and deregulates RUNX1 target genes RUNX1-ETO blocks myeloid differentiation by rapidly downregulating SPI1 and CEBPA The impact of RUNX1-ETO induction is cell type specific
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Affiliation(s)
- Monica Nafria
- Institute for Cancer and Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B15 2TT, UK; Murdoch Children's Research Institute, The Royal Children's Hospital, Flemington Road, Parkville, VIC 3052, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC 3052, Australia
| | - Peter Keane
- Institute for Cancer and Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B15 2TT, UK
| | - Elizabeth S Ng
- Murdoch Children's Research Institute, The Royal Children's Hospital, Flemington Road, Parkville, VIC 3052, Australia
| | - Edouard G Stanley
- Murdoch Children's Research Institute, The Royal Children's Hospital, Flemington Road, Parkville, VIC 3052, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC 3052, Australia; Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC 3800, Australia
| | - Andrew G Elefanty
- Murdoch Children's Research Institute, The Royal Children's Hospital, Flemington Road, Parkville, VIC 3052, Australia; Department of Paediatrics, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Parkville, VIC 3052, Australia; Department of Anatomy and Developmental Biology, Monash University, Clayton, VIC 3800, Australia.
| | - Constanze Bonifer
- Institute for Cancer and Genomic Sciences, College of Medicine and Dentistry, University of Birmingham, Birmingham B15 2TT, UK.
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5
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Johnson DT, Davis AG, Zhou JH, Ball ED, Zhang DE. MicroRNA let-7b downregulates AML1-ETO oncogene expression in t(8;21) AML by targeting its 3'UTR. Exp Hematol Oncol 2021; 10:8. [PMID: 33531067 PMCID: PMC7856722 DOI: 10.1186/s40164-021-00204-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 01/22/2021] [Indexed: 01/06/2023] Open
Abstract
Background Acute myeloid leukemia (AML) with the t(8;21)(q22;q22) chromosomal translocation is among the most common subtypes of AML and produces the AML1-ETO (RUNX1-ETO, RUNX1-RUNX1T1) oncogenic fusion gene. AML1-ETO functions as an aberrant transcription factor which plays a key role in blocking normal hematopoiesis. Thus, the expression of AML1-ETO is critical to t(8;21) AML leukemogenesis and maintenance. Post-transcriptional regulation of gene expression is often mediated through interactions between trans-factors and cis-elements within transcript 3′-untranslated regions (UTR). AML1-ETO uses the 3′UTR of the ETO gene, which is not normally expressed in hematopoietic cells. Therefore, the mechanisms regulating AML1-ETO expression via the 3’UTR are attractive therapeutic targets. Methods We used RNA-sequencing of t(8;21) patients and cell lines to examine the 3′UTR isoforms used by AML1-ETO transcripts. Using luciferase assay approaches, we test the relative contribution of 3′UTR cis elements to AML1-ETO expression. We further use let-7b microRNA mimics and anti-let-7b sponges for functional studies of t(8;21) AML cell lines. Results In this study, we examine the regulation of AML1-ETO via the 3’UTR. We demonstrate that AML1-ETO transcripts primarily use a 3.7 kb isoform of the ETO 3′UTR in both t(8;21) patients and cell lines. We identify a negative regulatory element within the AML1-ETO 3′UTR. We further demonstrate that the let-7b microRNA directly represses AML1-ETO through this site. Finally, we find that let-7b inhibits the proliferation of t(8;21) AML cell lines, rescues expression of AML1-ETO target genes, and promotes differentiation. Conclusions AML1-ETO is post-transcriptionally regulated by let-7b, which contributes to the leukemic phenotype of t(8;21) AML and may be important for t(8;21) leukemogenesis and maintenance.
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Affiliation(s)
- Daniel T Johnson
- Moores Cancer Center, University of California, La Jolla, San Diego, CA, USA.,Biological Sciences Graduate Program, University of California San Diego, La Jolla, San Diego, CA, USA.,Division of Biological Sciences, University of California San Diego, La Jolla, San Diego, CA, USA
| | - Amanda G Davis
- Moores Cancer Center, University of California, La Jolla, San Diego, CA, USA.,Biological Sciences Graduate Program, University of California San Diego, La Jolla, San Diego, CA, USA.,Division of Biological Sciences, University of California San Diego, La Jolla, San Diego, CA, USA
| | - Jie-Hua Zhou
- Moores Cancer Center, University of California, La Jolla, San Diego, CA, USA.,BMT Division, Department of Medicine, University of California San Diego, La Jolla, San Diego, CA, USA
| | - Edward D Ball
- Moores Cancer Center, University of California, La Jolla, San Diego, CA, USA.,BMT Division, Department of Medicine, University of California San Diego, La Jolla, San Diego, CA, USA
| | - Dong-Er Zhang
- Moores Cancer Center, University of California, La Jolla, San Diego, CA, USA. .,Biological Sciences Graduate Program, University of California San Diego, La Jolla, San Diego, CA, USA. .,Division of Biological Sciences, University of California San Diego, La Jolla, San Diego, CA, USA. .,Department of Pathology, University of California San Diego, La Jolla, San Diego, CA, USA.
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6
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Redondo Monte E, Wilding A, Leubolt G, Kerbs P, Bagnoli JW, Hartmann L, Hiddemann W, Chen-Wichmann L, Krebs S, Blum H, Cusan M, Vick B, Jeremias I, Enard W, Theurich S, Wichmann C, Greif PA. ZBTB7A prevents RUNX1-RUNX1T1-dependent clonal expansion of human hematopoietic stem and progenitor cells. Oncogene 2020; 39:3195-3205. [PMID: 32115572 PMCID: PMC7142018 DOI: 10.1038/s41388-020-1209-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 01/30/2020] [Accepted: 02/04/2020] [Indexed: 12/12/2022]
Abstract
ZBTB7A is frequently mutated in acute myeloid leukemia (AML) with t(8;21) translocation. However, the oncogenic collaboration between mutated ZBTB7A and the RUNX1–RUNX1T1 fusion gene in AML t(8;21) remains unclear. Here, we investigate the role of ZBTB7A and its mutations in the context of normal and malignant hematopoiesis. We demonstrate that clinically relevant ZBTB7A mutations in AML t(8;21) lead to loss of function and result in perturbed myeloid differentiation with block of the granulocytic lineage in favor of monocytic commitment. In addition, loss of ZBTB7A increases glycolysis and hence sensitizes leukemic blasts to metabolic inhibition with 2-deoxy-d-glucose. We observed that ectopic expression of wild-type ZBTB7A prevents RUNX1-RUNX1T1-mediated clonal expansion of human CD34+ cells, whereas the outgrowth of progenitors is enabled by ZBTB7A mutation. Finally, ZBTB7A expression in t(8;21) cells lead to a cell cycle arrest that could be mimicked by inhibition of glycolysis. Our findings suggest that loss of ZBTB7A may facilitate the onset of AML t(8;21), and that RUNX1-RUNX1T1-rearranged leukemia might be treated with glycolytic inhibitors.
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Affiliation(s)
- Enric Redondo Monte
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany.,German Cancer Consortium (DKTK), Partner Site Munich, 81377, Munich, Germany.,German Cancer Research Center (DKFZ), 69121, Heidelberg, Germany
| | - Anja Wilding
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany.,German Cancer Consortium (DKTK), Partner Site Munich, 81377, Munich, Germany.,German Cancer Research Center (DKFZ), 69121, Heidelberg, Germany
| | - Georg Leubolt
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany.,German Cancer Consortium (DKTK), Partner Site Munich, 81377, Munich, Germany.,German Cancer Research Center (DKFZ), 69121, Heidelberg, Germany
| | - Paul Kerbs
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany.,German Cancer Consortium (DKTK), Partner Site Munich, 81377, Munich, Germany.,German Cancer Research Center (DKFZ), 69121, Heidelberg, Germany
| | - Johannes W Bagnoli
- Anthropology & Human Genomics, Department of Biology II, LMU Munich, 82152, Martinsried, Germany
| | - Luise Hartmann
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany.,German Cancer Consortium (DKTK), Partner Site Munich, 81377, Munich, Germany.,German Cancer Research Center (DKFZ), 69121, Heidelberg, Germany
| | - Wolfgang Hiddemann
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany.,German Cancer Consortium (DKTK), Partner Site Munich, 81377, Munich, Germany.,German Cancer Research Center (DKFZ), 69121, Heidelberg, Germany
| | - Linping Chen-Wichmann
- Department of Transfusion Medicine, Cell Therapeutics and Hemostasis, University Hospital, LMU Munich, 81377, Munich, Germany
| | - Stefan Krebs
- Gene Center-Laboratory for Functional Genome Analysis, LMU Munich, 81377, Munich, Germany
| | - Helmut Blum
- Gene Center-Laboratory for Functional Genome Analysis, LMU Munich, 81377, Munich, Germany
| | - Monica Cusan
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany
| | - Binje Vick
- Research Unit Apoptosis in Hematopoietic Stem Cells, Helmholtz Center Munich, 81377, Munich, Germany
| | - Irmela Jeremias
- Research Unit Apoptosis in Hematopoietic Stem Cells, Helmholtz Center Munich, 81377, Munich, Germany
| | - Wolfgang Enard
- Anthropology & Human Genomics, Department of Biology II, LMU Munich, 82152, Martinsried, Germany
| | - Sebastian Theurich
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany.,Cancer & Immunometabolism Research Group, Gene Center, LMU Munich, 81377, Munich, Germany
| | - Christian Wichmann
- Department of Transfusion Medicine, Cell Therapeutics and Hemostasis, University Hospital, LMU Munich, 81377, Munich, Germany
| | - Philipp A Greif
- Department of Medicine III, University Hospital, LMU Munich, 81377, Munich, Germany. .,German Cancer Consortium (DKTK), Partner Site Munich, 81377, Munich, Germany. .,German Cancer Research Center (DKFZ), 69121, Heidelberg, Germany.
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7
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Tataranni T, Mazzoccoli C, Agriesti F, De Luca L, Laurenzana I, Simeon V, Ruggieri V, Pacelli C, Della Sala G, Musto P, Capitanio N, Piccoli C. Deferasirox drives ROS-mediated differentiation and induces interferon-stimulated gene expression in human healthy haematopoietic stem/progenitor cells and in leukemia cells. Stem Cell Res Ther 2019; 10:171. [PMID: 31196186 PMCID: PMC6567456 DOI: 10.1186/s13287-019-1293-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2019] [Revised: 05/15/2019] [Accepted: 05/31/2019] [Indexed: 12/11/2022] Open
Abstract
Background Administration of the iron chelator deferasirox (DFX) in transfusion-dependent patients occasionally results in haematopoiesis recovery by a mechanism remaining elusive. This study aimed to investigate at a molecular level a general mechanism underlying DFX beneficial effects on haematopoiesis, both in healthy and pathological conditions. Methods Human healthy haematopoietic stem/progenitor cells (HS/PCs) and three leukemia cell lines were treated with DFX. N-Acetyl cysteine (NAC) and fludarabine were added as antioxidant and STAT1 inhibitor, respectively. In vitro colony-forming assays were assessed both in healthy and in leukemia cells. Intracellular and mitochondrial reactive oxygen species (ROS) as well as mitochondrial content were assessed by cytofluorimetric and confocal microscopy analysis; mtDNA was assessed by qRT-PCR. Differentiation markers were monitored by cytofluorimetric analysis. Gene expression analysis (GEA) was performed on healthy HS/PCs, and differently expressed genes were validated in healthy and leukemia cells by qRT-PCR. STAT1 expression and phosphorylation were assessed by Western blotting. Data were compared by an unpaired Student t test or one-way ANOVA. Results DFX, at clinically relevant concentrations, increased the clonogenic capacity of healthy human CD34+ HS/PCs to form erythroid colonies. Extension of this analysis to human-derived leukemia cell lines Kasumi-1, K562 and HL60 confirmed DFX capacity to upregulate the expression of specific markers of haematopoietic commitment. Notably, the abovementioned DFX-induced effects are all prevented by the antioxidant NAC and accompanied with overproduction of mitochondria-generated reactive oxygen species (ROS) and increase of mitochondrial content and mtDNA copy number. GEA unveiled upregulation of genes linked to interferon (IFN) signalling and tracked back to hyper-phosphorylation of STAT1. Treatment of leukemic cell lines with NAC prevented the DFX-mediated phosphorylation of STAT1 as well as the expression of the IFN-stimulated genes. However, STAT1 inhibition by fludarabine was not sufficient to affect differentiation processes in leukemic cell lines. Conclusions These findings suggest a significant involvement of redox signalling as a major regulator of multiple DFX-orchestrated events promoting differentiation in healthy and tumour cells. The understanding of molecular mechanisms underlying the haematological response by DFX would enable to predict patient’s ability to respond to the drug, to extend treatment to other patients or to anticipate the treatment, regardless of the iron overload. Electronic supplementary material The online version of this article (10.1186/s13287-019-1293-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Tiziana Tataranni
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, Rionero in Vulture, PZ, Italy
| | - Carmela Mazzoccoli
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, Rionero in Vulture, PZ, Italy
| | - Francesca Agriesti
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, Rionero in Vulture, PZ, Italy
| | - Luciana De Luca
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, Rionero in Vulture, PZ, Italy
| | - Ilaria Laurenzana
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, Rionero in Vulture, PZ, Italy
| | - Vittorio Simeon
- Department of Public, Clinical and Preventive Medicine, Medical Statistics Unit, University of Campania Luigi Vanvitelli, Caserta, Italy
| | - Vitalba Ruggieri
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, Rionero in Vulture, PZ, Italy
| | - Consiglia Pacelli
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Gerardo Della Sala
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, Rionero in Vulture, PZ, Italy
| | - Pellegrino Musto
- Hematology Department of Basilicata, IRCCS-CROB Referral Cancer Center of Basilicata, Rionero in Vulture, Italy
| | - Nazzareno Capitanio
- Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy
| | - Claudia Piccoli
- Laboratory of Pre-Clinical and Translational Research, IRCCS-CROB, Referral Cancer Center of Basilicata, Rionero in Vulture, PZ, Italy. .,Department of Clinical and Experimental Medicine, University of Foggia, Foggia, Italy.
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8
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Mandoli A, Singh AA, Prange KHM, Tijchon E, Oerlemans M, Dirks R, Ter Huurne M, Wierenga ATJ, Janssen-Megens EM, Berentsen K, Sharifi N, Kim B, Matarese F, Nguyen LN, Hubner NC, Rao NA, van den Akker E, Altucci L, Vellenga E, Stunnenberg HG, Martens JHA. The Hematopoietic Transcription Factors RUNX1 and ERG Prevent AML1-ETO Oncogene Overexpression and Onset of the Apoptosis Program in t(8;21) AMLs. Cell Rep 2017; 17:2087-2100. [PMID: 27851970 DOI: 10.1016/j.celrep.2016.08.082] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Revised: 05/06/2016] [Accepted: 08/16/2016] [Indexed: 01/24/2023] Open
Abstract
The t(8;21) acute myeloid leukemia (AML)-associated oncoprotein AML1-ETO disrupts normal hematopoietic differentiation. Here, we have investigated its effects on the transcriptome and epigenome in t(8,21) patient cells. AML1-ETO binding was found at promoter regions of active genes with high levels of histone acetylation but also at distal elements characterized by low acetylation levels and binding of the hematopoietic transcription factors LYL1 and LMO2. In contrast, ERG, FLI1, TAL1, and RUNX1 bind at all AML1-ETO-occupied regulatory regions, including those of the AML1-ETO gene itself, suggesting their involvement in regulating AML1-ETO expression levels. While expression of AML1-ETO in myeloid differentiated induced pluripotent stem cells (iPSCs) induces leukemic characteristics, overexpression increases cell death. We find that expression of wild-type transcription factors RUNX1 and ERG in AML is required to prevent this oncogene overexpression. Together our results show that the interplay of the epigenome and transcription factors prevents apoptosis in t(8;21) AML cells.
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Affiliation(s)
- Amit Mandoli
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Abhishek A Singh
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Koen H M Prange
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Esther Tijchon
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Marjolein Oerlemans
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Rene Dirks
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Menno Ter Huurne
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Albertus T J Wierenga
- Department of Hematology, University of Groningen and University Medical Center Groningen, P.O. Box 30001, 9700 RB Groningen, the Netherlands; Department of Laboratory Medicine, University of Groningen and University Medical Center Groningen, P.O. Box 30001, 9700 RB Groningen, the Netherlands
| | - Eva M Janssen-Megens
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Kim Berentsen
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Nilofar Sharifi
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Bowon Kim
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Filomena Matarese
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Luan N Nguyen
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Nina C Hubner
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Nagesha A Rao
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Emile van den Akker
- Sanquin Research Department of Hematopoiesis, P.O. Box 9190, 1006 AD Amsterdam, the Netherlands
| | - Lucia Altucci
- Dipartimento di Patologia Generale, Seconda Università degli Studi di Napoli, Vico Luigi de Crecchio 7, 80138 Napoli, Italy; Istituto di Genetica e Biofisica "Adriano Buzzati Traverso," Via P. Castellino 131, 80131 Napoli, Italy
| | - Edo Vellenga
- Department of Hematology, University of Groningen and University Medical Center Groningen, P.O. Box 30001, 9700 RB Groningen, the Netherlands
| | - Hendrik G Stunnenberg
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands
| | - Joost H A Martens
- Radboud University, Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, 6500 HB Nijmegen, the Netherlands; Dipartimento di Patologia Generale, Seconda Università degli Studi di Napoli, Vico Luigi de Crecchio 7, 80138 Napoli, Italy.
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9
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Yan JS, Li YD, Liu SH, Yin QQ, Liu XY, Xia L, Lu Y. The t(8;21) fusion protein RUNX1-ETO downregulates PKM2 in acute myeloid leukemia cells. Leuk Lymphoma 2017; 58:1985-1988. [PMID: 28092997 DOI: 10.1080/10428194.2016.1272690] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
MESH Headings
- Animals
- Carrier Proteins/genetics
- Carrier Proteins/metabolism
- Cell Line, Tumor
- Chromosomes, Human, Pair 21
- Chromosomes, Human, Pair 8
- Core Binding Factor Alpha 2 Subunit/genetics
- Core Binding Factor Alpha 2 Subunit/metabolism
- Disease Models, Animal
- Gene Expression Regulation, Leukemic
- Humans
- Leukemia, Myeloid, Acute/diagnosis
- Leukemia, Myeloid, Acute/genetics
- Membrane Proteins/genetics
- Membrane Proteins/metabolism
- Mice
- Mutation
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/metabolism
- Protein Binding
- RUNX1 Translocation Partner 1 Protein/genetics
- RUNX1 Translocation Partner 1 Protein/metabolism
- Response Elements
- Thyroid Hormones/genetics
- Thyroid Hormones/metabolism
- Translocation, Genetic
- Xenograft Model Antitumor Assays
- Thyroid Hormone-Binding Proteins
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Affiliation(s)
- Jin-Song Yan
- a Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education , Shanghai Jiao Tong University School of Medicine , Shanghai , China
- b Department of Hematology of the Second Hospital of Dalian Medical University , Institute of Hematopoietic Stem Cell Transplantation of Dalian Medical University , Dalian , China
| | - Yi-Dong Li
- c Department of Pathophysiology , Shanghai Second Military Medical University , Shanghai , China
| | - Su-Hui Liu
- b Department of Hematology of the Second Hospital of Dalian Medical University , Institute of Hematopoietic Stem Cell Transplantation of Dalian Medical University , Dalian , China
| | - Qian-Qian Yin
- a Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Xin-Yi Liu
- a Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Li Xia
- a Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education , Shanghai Jiao Tong University School of Medicine , Shanghai , China
| | - Ying Lu
- a Department of Pathophysiology, Key Laboratory of Cell Differentiation and Apoptosis of Ministry of Education , Shanghai Jiao Tong University School of Medicine , Shanghai , China
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10
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AML1-ETO requires enhanced C/D box snoRNA/RNP formation to induce self-renewal and leukaemia. Nat Cell Biol 2017. [PMID: 28650479 DOI: 10.1038/ncb3563] [Citation(s) in RCA: 130] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Leukaemogenesis requires enhanced self-renewal, which is induced by oncogenes. The underlying molecular mechanisms remain incompletely understood. Here, we identified C/D box snoRNAs and rRNA 2'-O-methylation as critical determinants of leukaemic stem cell activity. Leukaemogenesis by AML1-ETO required expression of the groucho-related amino-terminal enhancer of split (AES). AES functioned by inducing snoRNA/RNP formation via interaction with the RNA helicase DDX21. Similarly, global loss of C/D box snoRNAs with concomitant loss of rRNA 2'-O-methylation resulted in decreased leukaemia self-renewal potential. Genomic deletion of either C/D box snoRNA SNORD14D or SNORD35A suppressed clonogenic potential of leukaemia cells in vitro and delayed leukaemogenesis in vivo. We further showed that AML1-ETO9a, MYC and MLL-AF9 all enhanced snoRNA formation. Expression levels of C/D box snoRNAs in AML patients correlated closely with in vivo frequency of leukaemic stem cells. Collectively, these findings indicate that induction of C/D box snoRNA/RNP function constitutes an important pathway in leukaemogenesis.
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11
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Spirin P, Lebedev T, Orlova N, Morozov A, Poymenova N, Dmitriev SE, Buzdin A, Stocking C, Kovalchuk O, Prassolov V. Synergistic suppression of t(8;21)-positive leukemia cell growth by combining oridonin and MAPK1/ERK2 inhibitors. Oncotarget 2017; 8:56991-57002. [PMID: 28915648 PMCID: PMC5593619 DOI: 10.18632/oncotarget.18503] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2016] [Accepted: 04/18/2017] [Indexed: 01/03/2023] Open
Abstract
One of the most common chromosomal translocations in acute myeloid leukemia is t(8;21)(q22;q22), which results in the appearance of abnormal transcripts encoding for the fusion protein RUNX1-ETO. Therefore, this oncoprotein is considered to be a pertinent and promising target for treating t(8;21) leukemia. Previously, we have shown that downregulation of RUNX1-ETO leads to activation of intracellular signaling pathways enhancing cell survival and determined that the protein ERK2 can mediate activation of most of these pathways. Here we used a combination of oridonin (natural tetracycline diterpenoid), which has been shown to exhibit anti-RUNX1-ETO activity, and ERK2 kinase inhibitors. We found that treatment of leukemic t(8;21)-positive Kasumi-1 cells with oridonin cause decrease of phosphorylated ERK1/2. Treatment of these cells with ERK2 inhibitors makes them more sensitive to RUNX1-ETO inhibition with oridonin. Therefore we postulate that simultaneous inhibition of RUNX1-ETO and ERK2 cause synergistic effect on survival of leukemic cells.
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Affiliation(s)
- Pavel Spirin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Timofey Lebedev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Natalia Orlova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Alexey Morozov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Nadezhda Poymenova
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
| | - Sergey E Dmitriev
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia.,Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119992, Russia
| | - Anton Buzdin
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia.,Dmitry Rogachev Federal Research Center of Pediatric Hematology, Oncology and Immunology, Moscow 117997, Russia.,National Research Centre "Kurchatov Institute", Centre for Convergence of Nano-, Bio-, Information and Cognitive Sciences and Technologies, Moscow 123182, Russia
| | - Carol Stocking
- Department of Stem Cell Transplantation, University Medical Center Hamburg-Eppendorf, Hamburg 20246, Germany
| | - Olga Kovalchuk
- OncoFinder Ltd, Lethbridge, AB T1K7×8, Canada.,Department of Biological Sciences, University of Lethbridge, Lethbridge, AB T1K3M4, Canada
| | - Vladimir Prassolov
- Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, Moscow 119991, Russia
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12
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RUNX transcription factors at the interface of stem cells and cancer. Biochem J 2017; 474:1755-1768. [PMID: 28490659 DOI: 10.1042/bcj20160632] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 03/01/2017] [Accepted: 03/03/2017] [Indexed: 12/22/2022]
Abstract
The RUNX1 transcription factor is a critical regulator of normal haematopoiesis and its functional disruption by point mutations, deletions or translocations is a major causative factor leading to leukaemia. In the majority of cases, genetic changes in RUNX1 are linked to loss of function classifying it broadly as a tumour suppressor. Despite this, several recent studies have reported the need for a certain level of active RUNX1 for the maintenance and propagation of acute myeloid leukaemia and acute lymphoblastic leukaemia cells, suggesting an oncosupportive role of RUNX1. Furthermore, in solid cancers, RUNX1 is overexpressed compared with normal tissue, and RUNX factors have recently been discovered to promote growth of skin, oral, breast and ovarian tumour cells, amongst others. RUNX factors have key roles in stem cell fate regulation during homeostasis and regeneration of many tissues. Cancer cells appear to have corrupted these stem cell-associated functions of RUNX factors to promote oncogenesis. Here, we discuss current knowledge on the role of RUNX genes in stem cells and as oncosupportive factors in haematological malignancies and epithelial cancers.
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13
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Expression and regulation of C/EBPα in normal myelopoiesis and in malignant transformation. Blood 2017; 129:2083-2091. [PMID: 28179278 DOI: 10.1182/blood-2016-09-687822] [Citation(s) in RCA: 105] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Accepted: 10/14/2016] [Indexed: 12/13/2022] Open
Abstract
One of the most studied transcription factors in hematopoiesis is the leucine zipper CCAAT-enhancer binding protein α (C/EBPα), which is mainly involved in cell fate decisions for myeloid differentiation. Its involvement in acute myeloid leukemia (AML) is diverse, with patients frequently exhibiting mutations, deregulation of gene expression, or alterations in the function of C/EBPα. In this review, we emphasize the importance of C/EBPα for neutrophil maturation, its role in myeloid priming of hematopoietic stem and progenitor cells, and its indispensable requirement for AML development. We discuss that mutations in the open reading frame of CEBPA lead to an altered C/EBPα function, affecting the expression of downstream genes and consequently deregulating myelopoiesis. The emerging transcriptional mechanisms of CEBPA are discussed based on recent studies. Novel insights on how these mechanisms may be deregulated by oncoproteins or mutations/variants in CEBPA enhancers are suggested in principal to reveal novel mechanisms of how CEBPA is deregulated at the transcriptional level.
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14
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AML1/ETO accelerates cell migration and impairs cell-to-cell adhesion and homing of hematopoietic stem/progenitor cells. Sci Rep 2016; 6:34957. [PMID: 27713544 PMCID: PMC5054523 DOI: 10.1038/srep34957] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2016] [Accepted: 09/20/2016] [Indexed: 12/16/2022] Open
Abstract
The AML1/ETO fusion protein found in acute myeloid leukemias functions as a transcriptional regulator by recruiting co-repressor complexes to its DNA binding site. In order to extend the understanding of its role in preleukemia, we expressed AML1/ETO in a murine immortalized pluripotent hematopoietic stem/progenitor cell line, EML C1, and found that genes involved in functions such as cell-to-cell adhesion and cell motility were among the most significantly regulated as determined by RNA sequencing. In functional assays, AML1/ETO-expressing cells showed a decrease in adhesion to stromal cells, an increase of cell migration rate in vitro, and displayed an impairment in homing and engraftment in vivo upon transplantation into recipient mice. Our results suggest that AML1/ETO expression determines a more mobile and less adherent phenotype in preleukemic cells, therefore altering the interaction with the hematopoietic niche, potentially leading to the migration across the bone marrow barrier and to disease progression.
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15
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New insights into transcriptional and leukemogenic mechanisms of AML1-ETO and E2A fusion proteins. ACTA ACUST UNITED AC 2016; 11:285-304. [PMID: 28261265 DOI: 10.1007/s11515-016-1415-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
BACKGROUND Nearly 15% of acute myeloid leukemia (AML) cases are caused by aberrant expression of AML1-ETO, a fusion protein generated by the t(8;21) chromosomal translocation. Since its discovery, AML1-ETO has served as a prototype to understand how leukemia fusion proteins deregulate transcription to promote leukemogenesis. Another leukemia fusion protein, E2A-Pbx1, generated by the t(1;19) translocation, is involved in acute lymphoblastic leukemias (ALLs). While AML1-ETO and E2A-Pbx1 are structurally unrelated fusion proteins, we have recently shown that a common axis, the ETO/E-protein interaction, is involved in the regulation of both fusion proteins, underscoring the importance of studying protein-protein interactions in elucidating the mechanisms of leukemia fusion proteins. OBJECTIVE In this review, we aim to summarize these new developments while also providing a historic overview of the related early studies. METHODS A total of 218 publications were reviewed in this article, a majority of which were published after 2004.We also downloaded 3D structures of AML1-ETO domains from Protein Data Bank and provided a systematic summary of their structures. RESULTS By reviewing the literature, we summarized early and recent findings on AML1-ETO, including its protein-protein interactions, transcriptional and leukemogenic mechanisms, as well as the recently reported involvement of ETO family corepressors in regulating the function of E2A-Pbx1. CONCLUSION While the recent development in genomic and structural studies has clearly demonstrated that the fusion proteins function by directly regulating transcription, a further understanding of the underlying mechanisms, including crosstalk with other transcription factors and cofactors, and the protein-protein interactions in the context of native proteins, may be necessary for the development of highly targeted drugs for leukemia therapy.
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16
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Cheng CK, Chan NPH, Wan TSK, Lam LY, Cheung CHY, Wong THY, Ip RKL, Wong RSM, Ng MHL. Helicase-like transcription factor is a RUNX1 target whose downregulation promotes genomic instability and correlates with complex cytogenetic features in acute myeloid leukemia. Haematologica 2016; 101:448-57. [PMID: 26802049 DOI: 10.3324/haematol.2015.137125] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 01/13/2016] [Indexed: 12/27/2022] Open
Abstract
Helicase-like transcription factor is a SWI/SNF chromatin remodeling factor involved in various biological processes. However, little is known about its role in hematopoiesis. In this study, we measured helicase-like transcription factor mRNA expression in the bone marrow of 204 adult patients with de novo acute myeloid leukemia. Patients were dichotomized into low and high expression groups at the median level for clinicopathological correlations. Helicase-like transcription factor levels were dramatically reduced in the low expression patient group compared to those in the normal controls (n=40) (P<0.0001). Low helicase-like transcription factor expression correlated positively with French-American-British M4/M5 subtypes (P<0.0001) and complex cytogenetic abnormalities (P=0.02 for ≥3 abnormalities;P=0.004 for ≥5 abnormalities) but negatively with CEBPA double mutations (P=0.012). Also, low expression correlated with poorer overall (P=0.005) and event-free (P=0.006) survival in the intermediate-risk cytogenetic subgroup. Consistent with the more aggressive disease associated with low expression, helicase-like transcription factor knockdown in leukemic cells promoted proliferation and chromosomal instability that was accompanied by downregulation of mitotic regulators and impaired DNA damage response. The significance of helicase-like transcription factor in genome maintenance was further indicated by its markedly elevated expression in normal human CD34(+)hematopoietic stem cells. We further demonstrated that helicase-like transcription factor was a RUNX1 target and transcriptionally repressed by RUNX1-ETO and site-specific DNA methylation through a duplicated RUNX1 binding site in its promoter. Taken together, our findings provide new mechanistic insights on genomic instability linked to helicase-like transcription factor deregulation, and strongly suggest a tumor suppressor function of the SWI/SNF protein in acute myeloid leukemia.
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Affiliation(s)
- Chi Keung Cheng
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina
| | - Natalie P H Chan
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina
| | - Thomas S K Wan
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina
| | - Lai Ying Lam
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina
| | - Coty H Y Cheung
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina
| | - Terry H Y Wong
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina
| | - Rosalina K L Ip
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina
| | - Raymond S M Wong
- Department of Medicine and Therapeutics, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina Sir Y. K. Pao Centre for Cancer, Prince of Wales Hospital, Hong Kong, Cina
| | - Margaret H L Ng
- Department of Anatomical and Cellular Pathology, Prince of Wales Hospital, The Chinese University of Hong Kong, Cina State Key Laboratory in Oncology in South China, The Chinese University of Hong Kong, Cina
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17
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Esculetin Downregulates the Expression of AML1-ETO and C-Kit in Kasumi-1 Cell Line by Decreasing Half-Life of mRNA. JOURNAL OF ONCOLOGY 2015; 2015:781473. [PMID: 25861270 PMCID: PMC4377501 DOI: 10.1155/2015/781473] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 02/23/2015] [Indexed: 01/05/2023]
Abstract
One of the most frequent genetic aberrations in acute myeloid leukemia (AML) is chromosomal translocation between AML1/RUNX1 on chromosome 21 and ETO gene on chromosome 8 resulting in the expression of chimeric oncogene AML1-ETO. Although patients with t(8;21) translocation have good prognosis, 5-year survival is observed only in 50% of the cases. AML1-ETO translocation is usually accompanied by overexpression of mutant C-Kit, a tyrosine kinase, which contributes to uncontrolled proliferation of premature blood cells leading to relapse and poor prognosis. We illustrate the potential use of esculetin on leukemic cell line, Kasumi-1, bearing t(8;21) translocation and mutated C-Kit gene. Esculetin decreases the expression of AML1-ETO at both protein and transcript level within 24 hours of treatment. Half-life of AML1-ETO mRNA was reduced from 7 hours to 1.5 hours. Similarly half-life of C-Kit mRNA was reduced to 2 hours from 5 hours in esculetin treated cells. Esculetin also perturbed the expression of ectopically expressed AML1-ETO in U937 cells. The decreased expression of AML1-ETO chimeric gene was associated with increased expression of LAT1 and RUNX3 genes, targets of AML1. We envisage that discovery of a drug candidate which could target both these mutated genes would be a considerable breakthrough for future application.
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18
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Activating c-KIT mutations confer oncogenic cooperativity and rescue RUNX1/ETO-induced DNA damage and apoptosis in human primary CD34+ hematopoietic progenitors. Leukemia 2014; 29:279-89. [PMID: 24897507 PMCID: PMC4320295 DOI: 10.1038/leu.2014.179] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 05/08/2014] [Accepted: 06/02/2014] [Indexed: 02/06/2023]
Abstract
The RUNX1/ETO (RE) fusion protein, which originates from the t(8;21) chromosomal rearrangement, is one of the most frequent translocation products found in de novo acute myeloid leukemia (AML). In RE leukemias, activated forms of the c-KIT tyrosine kinase receptor are frequently found, thereby suggesting oncogenic cooperativity between these oncoproteins in the development and maintenance of t(8;21) malignancies. In this report, we show that activated c-KIT cooperates with a C-terminal truncated variant of RE, REtr, to expand human CD34+ hematopoietic progenitors ex vivo. CD34+ cells expressing both oncogenes resemble the AML-M2 myeloblastic cell phenotype, in contrast to REtr-expressing cells which largely undergo granulocytic differentiation. Oncogenic c-KIT amplifies REtr-depended clonogenic growth and protects cells from exhaustion. Activated c-KIT reverts REtr-induced DNA damage and apoptosis. In the presence of activated c-KIT, REtr-downregulated DNA-repair genes are re-expressed leading to an enhancement of DNA-repair efficiency via homologous recombination. Together, our results provide new mechanistic insight into REtr and c-KIT oncogenic cooperativity and suggest that augmented DNA repair accounts for the increased chemoresistance observed in t(8;21)-positive AML patients with activated c-KIT mutations. This cell-protective mechanism might represent a new therapeutic target, as REtr cells with activated c-KIT are highly sensitive to pharmacological inhibitors of DNA repair.
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19
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DeKelver RC, Lewin B, Weng S, Yan M, Biggs J, Zhang DE. RUNX1-ETO induces a type I interferon response which negatively effects t(8;21)-induced increased self-renewal and leukemia development. Leuk Lymphoma 2014; 55:884-91. [PMID: 23772668 PMCID: PMC3987666 DOI: 10.3109/10428194.2013.815351] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The 8;21 translocation is the most common chromosomal aberration occurring in acute myeloid leukemia (AML). This translocation causes expression of the RUNX1-ETO (AML1-ETO) fusion protein, which cooperates with additional mutations in leukemia development. We report here that interferons (IFNs) and IFN-stimulated genes are a group of genes consistently up-regulated by RUNX1-ETO in both human and murine models. RUNX1-ETO-induced up-regulation of IFN-stimulated genes occurs primarily via type I IFN signaling with a requirement for the IFNAR complex. Addition of exogenous IFN in vitro significantly reduces the increase in self-renewal potential induced by both RUNX1-ETO and its leukemogenic splicing isoform RUNX1-ETO9a. Finally, loss of type I IFN signaling via knockout of Ifnar1 significantly accelerates leukemogenesis in a t(8;21) murine model. This demonstrates the role of increased IFN signaling as an important factor inhibiting t(8;21) fusion protein function and leukemia development and supports the use of type I IFNs in the treatment of AML.
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MESH Headings
- Animals
- Cell Line, Tumor
- Cell Transformation, Neoplastic/genetics
- Chromosomes, Human, Pair 21
- Chromosomes, Human, Pair 8
- Core Binding Factor Alpha 2 Subunit/genetics
- Disease Models, Animal
- Gene Expression Regulation, Leukemic/drug effects
- Humans
- Interferon Type I/pharmacology
- Leukemia/genetics
- Leukemia/metabolism
- Mice
- Mice, Knockout
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/metabolism
- Proto-Oncogene Proteins/genetics
- RUNX1 Translocation Partner 1 Protein
- Receptor, Interferon alpha-beta/deficiency
- Receptor, Interferon alpha-beta/genetics
- Receptor, Interferon alpha-beta/metabolism
- Transcription Factors/genetics
- Translocation, Genetic
- U937 Cells
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Affiliation(s)
- Russell C. DeKelver
- Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
| | - Benjamin Lewin
- Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
| | - Stephanie Weng
- Department of Biomedical Sciences, University of California San Diego, La Jolla, CA, USA
| | - Ming Yan
- Moores Cancer Center, University of California San Diego, La Jolla, CA, USA
| | - Joseph Biggs
- Moores Cancer Center, University of California San Diego, La Jolla, CA, USA
| | - Dong-Er Zhang
- Division of Biological Sciences, University of California San Diego, La Jolla, CA, USA
- Department of Biomedical Sciences, University of California San Diego, La Jolla, CA, USA
- Moores Cancer Center, University of California San Diego, La Jolla, CA, USA
- Department of Pathology, University of California San Diego, La Jolla, CA, USA
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20
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Fu L, Huang W, Jing Y, Jiang M, Zhao Y, Shi J, Huang S, Xue X, Zhang Q, Tang J, Dou L, Wang L, Nervi C, Li Y, Yu L. AML1-ETO triggers epigenetic activation of early growth response gene l, inducing apoptosis in t(8;21) acute myeloid leukemia. FEBS J 2014; 281:1123-31. [PMID: 24314118 DOI: 10.1111/febs.12673] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2013] [Revised: 11/06/2013] [Accepted: 12/02/2013] [Indexed: 11/30/2022]
Abstract
The t(8;21)(q22;q22) translocation is the most common chromosomal translocation in acute myeloid leukemia (AML), and it gives rise to acute myeloid gene 1 (AML1)-myeloid transforming gene 8 (ETO)-positive AML, which has a relatively favorable prognosis. However, the molecular mechanism related to a favorable prognosis in AML1-ETO-positive AML is still not fully understood. Our results show that the AML1-ETO fusion protein triggered activation of early growth response gene l (EGR1) by binding at AML1-binding sites on the EGR1 promoter and, subsequently, recruiting acetyltransferase P300, which is known to acetylate histones. However, AML1-ETO could not recruit DNA methyltransferases and histone deacetylases; therefore, EGR1 expression was affected by histone acetylation but not by DNA methylation. Both transcription and translation of EGR1 were higher in AML1-ETO-positive AML cell lines than in AML1-ETO-negative AML cell lines, owing to acetylation. Furthermore, when AML1-ETO-positive AML cell lines were treated with C646 (P300 inhibitor) and trichostatin A (histone deacetylase inhibitor), EGR1 expression was significantly decreased and increased, respectively. In addition, treatment with 5-azacytidine (methyltransferase inhibitor) did not cause any significant change in EGR1 expression. Overexpression of EGR1 inhibited cell proliferation and promoted apoptosis, and EGR1 knockout promoted cell proliferation. Thus, EGR1 could be a novel prognostic factor for a favorable outcome in AML1-ETO-positive AML. The results of our study may explain the molecular mechanisms underlying the favorable prognosis in AML1-ETO-positive AML.
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Affiliation(s)
- Lin Fu
- Department of Hematology, Chinese PLA General Hospital, Beijing, China; Nankai University School of Medicine, Tianjin, China
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21
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Ben-Ami O, Friedman D, Leshkowitz D, Goldenberg D, Orlovsky K, Pencovich N, Lotem J, Tanay A, Groner Y. Addiction of t(8;21) and inv(16) acute myeloid leukemia to native RUNX1. Cell Rep 2013; 4:1131-43. [PMID: 24055056 DOI: 10.1016/j.celrep.2013.08.020] [Citation(s) in RCA: 115] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2013] [Revised: 07/03/2013] [Accepted: 08/08/2013] [Indexed: 12/11/2022] Open
Abstract
The t(8;21) and inv(16) chromosomal aberrations generate the oncoproteins AML1-ETO (A-E) and CBFβ-SMMHC (C-S). The role of these oncoproteins in acute myeloid leukemia (AML) etiology has been well studied. Conversely, the function of native RUNX1 in promoting A-E- and C-S-mediated leukemias has remained elusive. We show that wild-type RUNX1 is required for the survival of t(8;21)-Kasumi-1 and inv(16)-ME-1 leukemic cells. RUNX1 knockdown in Kasumi-1 cells (Kasumi-1(RX1-KD)) attenuates the cell-cycle mitotic checkpoint, leading to apoptosis, whereas knockdown of A-E in Kasumi-1(RX1-KD) rescues these cells. Mechanistically, a delicate RUNX1/A-E balance involving competition for common genomic sites that regulate RUNX1/A-E targets sustains the malignant cell phenotype. The broad medical significance of this leukemic cell addiction to native RUNX1 is underscored by clinical data showing that an active RUNX1 allele is usually preserved in both t(8;21) or inv(16) AML patients, whereas RUNX1 is frequently inactivated in other forms of leukemia. Thus, RUNX1 and its mitotic control targets are potential candidates for new therapeutic approaches.
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Affiliation(s)
- Oren Ben-Ami
- Department of Molecular Genetics, Weizmann Institute of Science, 76100 Rehovot, Israel
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22
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Zhuang WY, Cen JN, Zhao Y, Chen ZX. Epigenetic silencing of Bcl-2, CEBPA and p14(ARF) by the AML1-ETO oncoprotein contributing to growth arrest and differentiation block in the U937 cell line. Oncol Rep 2013; 30:185-92. [PMID: 23673926 DOI: 10.3892/or.2013.2459] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 04/05/2013] [Indexed: 11/06/2022] Open
Abstract
The AML1-ETO fusion transcription factor generated by the t(8;21) translocation is considered to deregulate the expression of genes that are crucial for normal differentiation and proliferation of hematopoietic progenitors, resulting in acute myelogenous leukemia by recruiting co-repressor complexes to DNA. To investigate the role of AML1-ETO in leukemogenesis, we transfected the cloned AML1-ETO cDNA and expressed the AML1-ETO protein in U937 myelomonocytic leukemia cells. By focusing on the anti-apoptotic gene Bcl-2, the key regulator gene of granulocytic differentiation CCAAT/enhancer-binding protein α (CEBPA) and the tumor suppressor gene p14(ARF), we found that both AML1-ETO-expressing cell lines and t(8;21) leukemia samples displayed low levels of these three genes. Chromatin immunoprecipitation assays demonstrated that Bcl-2, CEBPA and p14(ARF) were direct transcriptional targets of AML1-ETO. The universal binding of AML1-ETO to genomic DNA resulted in recruitment of methyl-CpG binding protein 2 (MeCP2), reduction of histone H3 or H4 acetylation and increased trimethylation of histone H3 lysine 9 as well as lysine 27 indicating that AML1-ETO induced heterochromatic silencing of Bcl-2, CEBPA and p14(ARF). These results suggested that the aberrant transcription factor AML1-ETO epigenetically silenced the function of the Bcl-2, CEBPA and p14(ARF) genes by inducing repressed chromatin configurations at their promoters through histone modifications.
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Affiliation(s)
- Wen-Yue Zhuang
- The First Affiliated Hospital, Soochow University, Jiangsu Institute of Hematology, Key Laboratory of Thrombosis and Hemostasis, Ministry of Health, Suzhou, Jiangsu, P.R. China
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23
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Lo MC, Peterson LF, Yan M, Cong X, Jin F, Shia WJ, Matsuura S, Ahn EY, Komeno Y, Ly M, Ommen HB, Chen IM, Hokland P, Willman CL, Ren B, Zhang DE. Combined gene expression and DNA occupancy profiling identifies potential therapeutic targets of t(8;21) AML. Blood 2012; 120:1473-84. [PMID: 22740448 PMCID: PMC3423785 DOI: 10.1182/blood-2011-12-395335] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 06/16/2012] [Indexed: 12/24/2022] Open
Abstract
Chromosome translocation 8q22;21q22 [t(8;21)] is commonly associated with acute myeloid leukemia (AML), and the resulting AML1-ETO fusion proteins are involved in the pathogenesis of AML. To identify novel molecular and therapeutic targets, we performed combined gene expression microarray and promoter occupancy (ChIP-chip) profiling using Lin(-)/Sca1(-)/cKit(+) cells, the major leukemia cell population, from an AML mouse model induced by AML1-ETO9a (AE9a). Approximately 30% of the identified common targets of microarray and ChIP-chip assays overlap with the human t(8;21)-gene expression molecular signature. CD45, a protein tyrosine phosphatase and a negative regulator of cytokine/growth factor receptor and JAK/STAT signaling, is among those targets. Its expression is substantially down-regulated in leukemia cells. Consequently, JAK/STAT signaling is enhanced. Re-expression of CD45 suppresses JAK/STAT activation, delays leukemia development, and promotes apoptosis of t(8;21)-positive cells. This study demonstrates the benefit of combining gene expression and promoter occupancy profiling assays to identify molecular and potential therapeutic targets in human cancers and describes a previously unappreciated signaling pathway involving t(8;21) fusion proteins, CD45, and JAK/STAT, which could be a potential novel target for treating t(8;21) AML.
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MESH Headings
- Animals
- Antineoplastic Agents/therapeutic use
- Cell Line, Tumor
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/pathology
- Chromatin Immunoprecipitation
- Chromosomes, Human, Pair 21/genetics
- Chromosomes, Human, Pair 8/genetics
- DNA, Neoplasm/metabolism
- Enzyme Activation
- Gene Expression Profiling
- Gene Expression Regulation, Leukemic
- Gene Regulatory Networks/genetics
- Genes, Neoplasm/genetics
- Humans
- Janus Kinases/metabolism
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/genetics
- Leukocyte Common Antigens/metabolism
- Mice
- Oligonucleotide Array Sequence Analysis
- Promoter Regions, Genetic/genetics
- Reproducibility of Results
- STAT Transcription Factors/metabolism
- Signal Transduction/genetics
- Translocation, Genetic
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Affiliation(s)
- Miao-Chia Lo
- Moores Cancer Center, University of California-San Diego, La Jolla, CA 92093, USA
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24
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Runx1 deletion or dominant inhibition reduces Cebpa transcription via conserved promoter and distal enhancer sites to favor monopoiesis over granulopoiesis. Blood 2012; 119:4408-18. [PMID: 22451420 DOI: 10.1182/blood-2011-12-397091] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Deletion of Runx1 in adult mice produces a myeloproliferative phenotype. We now find that Runx1 gene deletion increases marrow monocyte while reducing granulocyte progenitors and that exogenous RUNX1 rescues granulopoiesis. Deletion of Runx1 reduces Cebpa mRNA in lineage-negative marrow cells and in granulocyte-monocyte progenitors or common myeloid progenitors. Pu.1 mRNA is also decreased, but to a lesser extent. We also transduced marrow with dominant-inhibitory RUNX1a. As with Runx1 gene deletion, RUNX1a expands lineage-Sca-1+c-kit+ and myeloid cells, increased monocyte CFUs relative to granulocyte CFUs, and reduced Cebpa mRNA. Runx1 binds a conserved site in the Cebpa promoter and binds 4 sites in a conserved 450-bp region located at +37 kb; mutation of the enhancer sites reduces activity 6-fold in 32Dcl3 myeloid cells. Endogenous Runx1 binds the promoter and putative +37 kb enhancer as assessed by ChIP, and RUNX1-ER rapidly induces Cebpa mRNA in these cells, even in cycloheximide, consistent with direct gene regulation. The +37 kb region contains strong H3K4me1 histone modification and p300-binding, as often seen with enhancers. Finally, exogenous C/EBPα increases granulocyte relative to monocyte progenitors in Runx1-deleted marrow cells. Diminished CEBPA transcription and consequent impairment of myeloid differentiation may contribute to leukemic transformation in acute myeloid leukemia cases associated with decreased RUNX1 activity.
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25
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Zapotocky M, Mejstrikova E, Smetana K, Stary J, Trka J, Starkova J. Valproic acid triggers differentiation and apoptosis in AML1/ETO-positive leukemic cells specifically. Cancer Lett 2012; 319:144-153. [PMID: 22261333 DOI: 10.1016/j.canlet.2011.12.041] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2011] [Revised: 12/04/2011] [Accepted: 12/25/2011] [Indexed: 01/07/2023]
Abstract
Valproic acid (VPA) has extensive effects on leukemic blasts through its inhibition of histone deacetylases. The main goal of this study was to identify the subgroup of patients who may benefit most from VPA treatment. We examined the significance of t(8;21) chromosomal aberration for VPA treatment response among acute myeloid leukemia (AML) patients by direct comparison of AML1/ETO-negative vs. positive leukemic cell-lines as well as bone marrow blasts from AML patients. In t(8;21) AML, leukemogenesis is supposed to be induced via aberrant recruitment of histone deacetylases. AML cell lines of different genotypes (Kasumi-1, Kasumi-6, MV4;11, K562) and diagnostic bone marrow samples from patients were treated with VPA. VPA induced apoptosis in AML1/ETO-positive and MLL-AF4-positive cells in a dose-dependent manner. Differentiation, as indicated by changes in immunophenotype, was observed only in AML1/ETO-positive cells. VPA increased the expression of AML1 target genes - PU.1, C/EBPa, BPI and IGFBP7 only in AML1/ETO-positive cells. This AML1/ETO-specific effect was confirmed also using patient blasts isolated at the time of diagnosis. AML1/ETO-positive leukemia shows specific mechanism of VPA residing from differentiation followed by apoptosis that is accompanied by an increase in the expression of repressed AML1 target genes. Our data suggest that AML1/ETO-positive patients might derive the greatest benefit from VPA treatment.
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Affiliation(s)
- Michal Zapotocky
- CLIP, Department of Pediatric Hematology and Oncology, Charles University, 2nd Medical School, Prague, Czech Republic
| | - Ester Mejstrikova
- CLIP, Department of Pediatric Hematology and Oncology, Charles University, 2nd Medical School, Prague, Czech Republic
| | - Karel Smetana
- Institute of Hematology and Blood Transfusion, Charles University, 1st Medical School, Prague, Czech Republic
| | - Jan Stary
- CLIP, Department of Pediatric Hematology and Oncology, Charles University, 2nd Medical School, Prague, Czech Republic
| | - Jan Trka
- CLIP, Department of Pediatric Hematology and Oncology, Charles University, 2nd Medical School, Prague, Czech Republic.
| | - Julia Starkova
- CLIP, Department of Pediatric Hematology and Oncology, Charles University, 2nd Medical School, Prague, Czech Republic
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26
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Runx1 loss minimally impacts long-term hematopoietic stem cells. PLoS One 2011; 6:e28430. [PMID: 22145044 PMCID: PMC3228772 DOI: 10.1371/journal.pone.0028430] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 11/08/2011] [Indexed: 12/14/2022] Open
Abstract
RUNX1 encodes a DNA binding subunit of the core-binding transcription factors and is frequently mutated in acute leukemia, therapy-related leukemia, myelodysplastic syndrome, and chronic myelomonocytic leukemia. Mutations in RUNX1 are thought to confer upon hematopoietic stem cells (HSCs) a pre-leukemic state, but the fundamental properties of Runx1 deficient pre-leukemic HSCs are not well defined. Here we show that Runx1 deficiency decreases both apoptosis and proliferation, but only minimally impacts the frequency of long term repopulating HSCs (LT-HSCs). It has been variously reported that Runx1 loss increases LT-HSC numbers, decreases LT-HSC numbers, or causes age-related HSC exhaustion. We attempt to resolve these discrepancies by showing that Runx1 deficiency alters the expression of several key HSC markers, and that the number of functional LT-HSCs varies depending on the criteria used to score them. Finally, we identify genes and pathways, including the cell cycle and p53 pathways that are dysregulated in Runx1 deficient HSCs.
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27
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Secreted-frizzled related protein 1 is a transcriptional repression target of the t(8;21) fusion protein in acute myeloid leukemia. Blood 2011; 118:6638-48. [PMID: 22031861 DOI: 10.1182/blood-2011-05-354712] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Secreted-frizzled related proteins (SFRPs) are modulators of the Wnt signaling pathway that is closely involved in normal and malignant hematopoiesis. Epigenetic deregulation of Wnt modulators leading to aberrant signaling has been reported in adult patients with acute myeloid leukemia (AML), but its occurrence in childhood patients with AML and the role of individual modulators are unclear. In this study, we examined SFRP1, SFRP2, SFRP4, and SFRP5 promoter methylation in 83 patients with AML (59 children and 24 adults) and found preferential SFRP1 methylation and mRNA down-regulation in the prognostically favorable subgroup of AML with t(8;21) translocation. Among the 4 genes, SFRP1 methylation independently predicted prolonged event-free and relapse-free survivals in childhood patients with nonacute promyelocytic leukemia with nonadverse cytogenetics. Mechanistically, we further demonstrated that RUNX1-ETO, the t(8;21) fusion product, specifically bound the SFRP1 promoter and repressed its transcription via a consensus RUNX binding site. In t(8;21)-leukemia cells, SFRP1 selectively inhibited canonical Wnt signaling and cellular proliferation that were associated with concomitant down-regulation of Wnt/β-catenin target genes, including CCND1 and MYC. Taken together, we identified SFRP1 as a transcriptional repression target of the t(8;21) fusion protein and demonstrated a novel mechanism of Wnt activation in a specific subtype of AML.
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28
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The HDAC class I-specific inhibitor entinostat (MS-275) effectively relieves epigenetic silencing of the LAT2 gene mediated by AML1/ETO. Oncogene 2011; 30:3062-72. [PMID: 21577204 DOI: 10.1038/onc.2011.32] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
The chromosomal translocation (8;21) fuses the hematopoietic transcription factor AML1 (RUNX1) with ETO (RUNX1T1, MTG8), resulting in the leukemia-specific chimeric protein AML1/ETO. This fusion protein has been implicated in epigenetic silencing, recruiting histone deacetylases (HDACs) and DNA methyltransferases to target promoters. Previously, we have identified a novel in vivo AML1/ETO target gene, LAT2 (NTAL/LAB/WBSCR5), which is involved in FcɛR I, c-Kit, B-cell and T-cell receptor signalling. We have now addressed the molecular mechanisms of AML1/ETO-mediated LAT2 repression. In Kasumi-1 cells, where AML1/ETO bound to the LAT2 gene, small interfering RNA (siRNA)-mediated AML1/ETO depletion caused upregulation of LAT2, suggesting a possible direct mechanism of repression. Expression of AML1/ETO was associated with a decrease in acetylation of histones H3, H3K9 and H4, and an increase in H3K9 and H3K27 trimethylation. The class I-specific HDAC inhibitors entinostat (MS-275) and mocetinostat (MGCD0103) induced LAT2 expression specifically in AML1/ETO-expressing cells, resulting in induction of several activating histone marks on the LAT2 gene, including trimethylation of histone H3K4. The combination of entinostat and decitabine increased acetylation of histones H3 and H4, as well as LAT2 mRNA expression, in an at least additive fashion. In conclusion, several repressive histone modifications mark the LAT2 gene in the presence of AML1/ETO, and LAT2 gene derepression is achieved by pharmacological inhibition of HDACs.
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29
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Abstract
Caspases, a family of aspartate-specific cysteine proteases, play a major role in apoptosis and a variety of physiological and pathological processes. Fourteen mammalian caspases have been identified and can be divided into two groups: inflammatory caspases and apoptotic caspases. Based on the structure and function, the apoptotic caspases are further grouped into initiator/apical caspases (caspase-2, -8, -9, and -10) and effector/executioner caspases (caspase-3, -6, and -7). In this paper, we discuss what we have learned about the role of individual effector caspase in mediating both apoptotic and nonapoptotic events, with special emphasis on leukemia-specific oncoproteins in relation to effector caspases.
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30
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Duque-Afonso J, Solari L, Essig A, Berg T, Pahl HL, Lübbert M. Regulation of the adaptor molecule LAT2, an in vivo target gene of AML1/ETO (RUNX1/RUNX1T1), during myeloid differentiation. Br J Haematol 2011; 153:612-22. [PMID: 21488857 DOI: 10.1111/j.1365-2141.2011.08586.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The leukaemia-specific fusion oncoprotein RUNX1/RUNX1T1 (AML1/ETO), resulting from the chromosomal translocation (8;21) in acute myeloid leukaemia (AML), imposes a striking genotype-phenotype relationship upon this distinct subtype of AML, which is mediated by multiple, co-ordinate downstream effects induced by this chimeric transcription factor. We previously identified the LAT2 gene, encoding the adaptor molecule LAT2 (NTAL, LAB), which is phosphorylated by KIT and has a role in mast cell and B-cell activation, as a target of the repressor activity of RUNX1/RUNX1T1. These results were confirmed and extended by demonstrating downregulation of the LAT2 protein in response to conditional RUNX1/RUNX1T1 expression, and its absence in primary AML with the t(8;21). In contrast, in a cohort of 43 AML patients, higher levels of LAT2 were associated with myelomonocytic features. Differentiation of HL-60 and NB4 cells towards granulocytes by all trans-retinoic acid (ATRA) resulted in downregulation of LAT2; conversely, it was upregulated during phorbol ester-induced monocytic differentiation of HL-60 cells. Forced expression of LAT2 in Kasumi-1 cells resulted in a striking block of ATRA- and phorbol ester-induced differentiation, implicating disturbances of the graded expression of this adaptor molecule in the maturation block of myeloid leukaemia cells.
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Affiliation(s)
- Jesús Duque-Afonso
- Department of Haematology/Oncology, University of Freiburg, Hugstetter Strasse 55, Freiburg, Germany
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31
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Abstract
Translocation (12;21), the most frequent chromosomal aberration in childhood acute lymphoblastic leukemia, creates TEL/AML1 fusion gene. Resulting hybrid protein was shown to have a role in pre-leukemia establishment. To address its role for leukemic cell survival, we applied RNA interference to silence TEL/AML1 in leukemic cells. We designed and tested 11 different oligonucleotides targeting the TEL/AML1 fusion site. Using most efficient siRNAs, we achieved an average of 74-86% TEL/AML1 protein knockdown in REH and UOC-B6 leukemic cells, respectively. TEL/AML1 silencing neither decreased cell viability, nor induced apoptosis. On the contrary, it resulted in the modest but significant increase in the S phase fraction and in higher proliferation rate. Opposite effects on cell cycle distribution and proliferation were induced by AML1 silencing, thus, supporting our hypothesis that TEL/AML1 may block AML1-mediated promotion of G1/S progression through the cell cycle. In line with the lack of major effect on phenotype, we found no significant changes in clonogenic potential and global gene expression pattern upon TEL/AML1 depletion. Our data suggest that though TEL/AML1 is important for the (pre)leukemic clone development, it may be dispensable for leukemic cell survival and would not be a suitable target for gene-specific therapy.
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32
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Guo H, Friedman AD. Phosphorylation of RUNX1 by cyclin-dependent kinase reduces direct interaction with HDAC1 and HDAC3. J Biol Chem 2010; 286:208-15. [PMID: 21059642 DOI: 10.1074/jbc.m110.149013] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
RUNX1 regulates formation of the definitive hematopoietic stem cell and its subsequent lineage maturation, and mutations of RUNX1 contribute to leukemic transformation. Phosphorylation of Ser-48, Ser-303, and Ser-424 by cyclin-dependent kinases (cdks) increases RUNX1 trans-activation activity without perturbing p300 interaction. We now find that endogenous RUNX1 interacts with endogenous HDAC1 or HDAC3. Mutation of the three RUNX1 serines to aspartic acid reduces co-immunoprecipitation with HDAC1 or HDAC3 when expressed in 293T cells; mutation of these three serines to alanine increases HDAC interaction, and mutation of each serine individually to aspartic acid also reduces these interactions. GST-RUNX1 isolated from bacterial extracts bound in vitro translated HDAC1 or HDAC3, and these interactions were weakened by mutation of Ser-48, Ser-303, and Ser-424 to aspartic acid. The ability of RUNX1 phosphorylation and not only serine to aspartic acid conversion to reduce HDAC1 binding was demonstrated using wild-type GST-RUNX1 phosphorylated in vitro using cdk1/cyclinB and by exposure of 293T cells transduced with RUNX1 and HDAC1 to roscovitine, a cdk inhibitor. Finally, RUNX1 or RUNX1(tripleD), in which Ser-48, Ser-303, and Ser-424 are mutated to aspartic acid, stimulated proliferation of transduced, lineage-negative murine marrow progenitors more potently than did RUNX1(tripleA), in which these serines are mutated to alanine, suggesting that stimulation of RUNX1 trans-activation by cdk-mediated reduction in HDAC interaction increases marrow progenitor cell proliferation.
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Affiliation(s)
- Hong Guo
- Division of Pediatric Oncology, The Johns Hopkins University School of Medicine, Baltimore, Maryland 21231, USA
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33
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Chevalier N, Solari ML, Becker H, Pantic M, Gärtner F, Maul-Pavicic A, Hübner J, Wäsch R, Schmitt-Gräff A, Lübbert M. Robust in vivo differentiation of t(8;21)-positive acute myeloid leukemia blasts to neutrophilic granulocytes induced by treatment with dasatinib. Leukemia 2010; 24:1779-81. [PMID: 20811401 DOI: 10.1038/leu.2010.151] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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34
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Abstract
Abstract
Introduction
The rational design of targeted therapies for acute myeloid leukemia (AML) requires the discovery of novel protein pathways in the systems biology of a specific AML subtype. We have shown that in the AML subtype with translocation t(8;21), the leukemic fusion protein AML1–ETO inhibits the function of transcription factors PU.1 and C/EBPα via direct protein–protein interaction. In addition, recently using proteomics, we have also shown that the AML subtypes differ in their proteome, interactome, and post-translational modifications.
Methods
We, therefore, hypothesized that the systematic identification of target proteins of AML1–ETO on a global proteome-wide level will lead to novel insights into the systems biology of t(8;21) AML on a post-genomic functional level. Thus, 6 h after inducible expression of AML1–ETO, protein expression changes were identified by two-dimensional gel electrophoresis and subsequent mass spectrometry analysis.
Results
Twenty-eight target proteins of AML1–ETO including prohibitin, NM23, HSP27, and Annexin1 were identified by MALDI-TOF mass spectrometry. AML1–ETO upregulated the differentiation inhibitory factor NM23 protein expression after 6 h, and the NM23 mRNA expression was also elevated in t(8;21) AML patient samples in comparison with normal bone marrow. AML1–ETO inhibited the ability of C/EBP transcription factors to downregulate the NM23 promoter. These data suggest a model in which AML1–ETO inhibits the C/EBP-induced downregulation of the NM23 promoter and thereby increases the protein level of differentiation inhibitory factor NM23.
Conclusions
Proteomic pathway discovery can identify novel functional pathways in AML, such as the AML1–ETO–C/EBP–NM23 pathway, as the main step towards a systems biology and therapy of AML.
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35
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Abstract
Abstract
RUNX1/ETO, the fusion protein resulting from the chromosomal translocation t(8;21), is one of the most frequent translocation products in acute myeloid leukemia. Several in vitro and in vivo studies have shown that the homo-tetramerization domain of ETO, the nervy homology region 2 (NHR2), is essential for RUNX1/ETO oncogenic activity. We analyzed the energetic contribution of individual amino acids within the NHR2 to RUNX1/ETO dimer-tetramer transition and found a clustered area of 5 distinct amino acids with strong contribution to the stability of tetramers. Substitution of these amino acids abolishes tetramer formation without affecting dimer formation. Similar to RUNX1/ETO monomers, dimers failed to bind efficiently to DNA and to alter expression of RUNX1-dependent genes. RUNX1/ETO dimers do not block myeloid differentiation, are unable to enhance the self-renewal capacity of hematopoietic progenitors, and fail to induce leukemia in a murine transplantation model. Our data reveal the existence of an essential structural motif (hot spot) at the NHR2 dimer-tetramer interface, suitable for a molecular intervention in t(8;21) leukemias.
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36
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Zhi L, Wang M, Rao Q, Yu F, Mi Y, Wang J. Enrichment of N-Cadherin and Tie2-bearing CD34+/CD38-/CD123+ leukemic stem cells by chemotherapy-resistance. Cancer Lett 2010; 296:65-73. [PMID: 20444543 DOI: 10.1016/j.canlet.2010.03.021] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 03/12/2010] [Accepted: 03/22/2010] [Indexed: 12/14/2022]
Abstract
Acute myeloid leukemia (AML) arises from genetic changes at the level of stem cell, various mutations have been elucidated, including AML1-ETO fusion gene has been shown as the representative target of cellular transformation for LSCs originating from hematopoietic stem cells (HSCs) compartment. LSCs resemble HSCs with respect to self-renewal capacity and chemotherapy-resistance. However, LSCs possess specific cell-surface markers, they are proposed to reside within the CD34(+)/CD38(-)/CD123(+) compartment. And the interaction mediated by adhesion molecules between LSCs and niche played a role in chemoresistance of LSCs. Therefore, study on the LSCs surface makers related to niche is helpful for the potential target therapy in the future. In this study, the proportions of CD34(+)/CD38(-)/CD123(+) LSCs compartment co-expressing the three adhesion molecules, N-Cadherin, Tie2 and CD44, respectively, from AML patients before and after chemotherapy were analyzed. We demonstrated N-Cadherin and Tie2 positive CD34(+)/CD38(-)/CD123(+) LSCs populations could be enriched by chemotherapy. Furthermore, AML1/ETO fusion signals and MDR1 expression were detected on the CD34(+)/CD38(-)/CD123(+) LSCs populations expressing N-Cadherin and Tie2. Therefore, N-Cadherin and Tie2 are probably the potential markers for identification of LSCs.
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Affiliation(s)
- Lei Zhi
- State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Science & Peking Union Medical College (CAMS & PUMC), PR China
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Lasa A, Carricondo M, Estivill C, Bussaglia E, Gich I, Brunet S, Aventin A, Sierra J, Nomdedéu JF. WT1 monitoring in core binding factor AML: Comparison with specific chimeric products. Leuk Res 2009; 33:1643-9. [DOI: 10.1016/j.leukres.2009.03.046] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2009] [Revised: 03/27/2009] [Accepted: 03/30/2009] [Indexed: 11/16/2022]
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38
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Zhang J, Gonit M, Salazar MD, Shatnawi A, Shemshedini L, Trumbly R, Ratnam M. C/EBPalpha redirects androgen receptor signaling through a unique bimodal interaction. Oncogene 2009; 29:723-38. [PMID: 19901962 DOI: 10.1038/onc.2009.373] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Nuclear expression of CCAAT enhancer binding protein-alpha (C/EBPalpha), which supports tissue differentiation through several antiproliferative protein-protein interactions, augurs terminal differentiation of prostate epithelial cells. C/EBPalpha is also a tumor suppressor, but in many tumors its antiproliferative interactions may be attenuated by de-phosphorylation. C/EBPalpha acts as a corepressor of the classical androgen response element (ARE)-mediated gene activation by the androgen receptor (AR), but this is paradoxical as the genotropic actions of AR are crucial not only for the growth of the prostate but also for its maintenance and function. We show that DNA-bound C/EPBalpha recruits AR to activate transcription. C/EBPalpha-dependent trans-activation by AR also overrode suppression of AREs by C/EBPalpha elsewhere in a promoter. This mechanism was remarkable in that its androgen dependence was apparently for nuclear translocation of AR; it was otherwise androgen independent, flutamide insensitive and tolerant to disruption of AR dimerization. Gene response profiles and global chromatin associations in situ supported the direct bimodal regulation of AR transcriptional signaling by C/EBPalpha. This unique mechanism explains the functional coordination between AR and C/EPBalpha in the prostate and also shows that hormone-refractory AR signaling in prostate cancer could occur through receptor tethering.
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Affiliation(s)
- J Zhang
- Department of Biochemistry and Cancer Biology, Medical University of Ohio, Toledo, OH 43614, USA
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Yin H, Lowery M, Glass J. In prostate cancer C/EBPalpha promotes cell growth by the loss of interactions with CDK2, CDK4, and E2F and by activation of AKT. Prostate 2009; 69:1001-16. [PMID: 19347879 DOI: 10.1002/pros.20947] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND The CCAAT/Enhancer binding protein alpha (C/EBPalpha) is an important transcription factor for granulopoiesis and adipogenesis. While decreased expression and mutation of C/EBPalpha has been found in several types of tumors, the role of C/EBPalpha in prostate cancer has not been well characterized. METHODS We quantitatively analyzed the immunochemical staining of prostate cancer tissue and examined the growth properties of prostate cancer cells stably expressing C/EBPalpha by measure growth curve, cell cycle, and anchorage independent colony formation, investigated the association of C/EBPalpha with E2Fs and CDKs by co-immunoprecipitation and examined the expression of CDKs and activation of AKT by Western blot analysis. RESULTS The ratio of C/EBPalpha expression between cancer cells close to the pseudolumen of glands and those nearer the basal cell layer was more than threefold greater than that seen in the normal prostate epithelium. Further, this ratio increased with increased Gleason score of the prostate cancer. Forced expression of C/EBPalpha in prostate cancer cell lines accelerated cell growth, stimulated cells into the S and G2 phases of cell cycle, and enhanced anchorage-independent colony formation. Simultaneously, forced expression of C/EBPalpha increased expression of CDK2/CDK4 and nuclear PP2A, and activated AKT. In addition, C/EBPalpha was no longer found associated with E2F1/E2F4 and CDK2/CDK4. AKT and PPA2 inhibitors restored both the anti-proliferation function of C/EBPalpha and the interaction between C/EBPalpha and E2F1/E2F4. CONCLUSION In prostate cancer cells C/EBPalpha cannot function as a tumor suppressor.
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Affiliation(s)
- Hong Yin
- Department of Medicine, Feist-Weiller Cancer Center, LSU Health Sciences Center, Shreveport, Louisiana 71130-3932, USA.
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40
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Abstract
Runx1 binds DNA in cooperation with CBFbeta to activate or repress transcription, dependent upon cellular context and interaction with a variety of co-activators and co-repressors. Runx1 is required for emergence of adult hematopoietic stem cells (HSC) during embryonic development and for lymphoid, myeloid, and megakaryocyte lineage maturation from HSC in adult marrow. Runx1 levels vary during the cell cycle, and Runx1 regulates G1 to S cell cycle progression. Both Cdk and ERK phosphorylate Runx1 to influence its interaction with co-repressors, and the Wnt effector LEF-1/TCF also modulates Runx1 activities. These links likely allow cytokines and signals from adjacent cells to influence HSC proliferation versus quiescence and the rate of progenitor expansion, in response to developmental or environmental demands. J. Cell. Physiol. 219: 520-524, 2009. (c) 2009 Wiley-Liss, Inc.
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Affiliation(s)
- Alan D Friedman
- Division of Pediatric Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
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41
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Global reduction of the epigenetic H3K79 methylation mark and increased chromosomal instability in CALM-AF10-positive leukemias. Blood 2009; 114:651-8. [PMID: 19443658 DOI: 10.1182/blood-2009-03-209395] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Chromosomal translocations generating fusion proteins are frequently found in human leukemias. The fusion proteins play an important role in leukemogenesis by subverting the function of one or both partner proteins. The leukemogenic CALM-AF10 fusion protein is capable of interacting with the histone H3 lysine 79 (H3K79)-specific methyltransferase hDOT1L through the fused AF10 moiety. This interaction leads to local H3K79 hypermethylation on Hoxa5 loci, which up-regulates the expression of Hoxa5 and contributes to leukemogenesis. However, the long latency of leukemogenesis of CALM-AF10 transgenic mice suggests that the direct effects of fusion oncogene are not sufficient for the induction of leukemia. In this study, we show that the CALM-AF10 fusion protein can also greatly reduce global H3K79 methylation in both human and murine leukemic cells by disrupting the AF10-mediated association of hDOT1L with chromatin. Cells with reduced H3K79 methylation are more sensitive to gamma-irradiation and display increased chromosomal instability. Consistently, leukemia patients harboring CALM-AF10 fusion have more secondary chromosomal aberrations. These findings suggest that chromosomal instability associated with global epigenetic alteration contributes to malignant transformation in certain leukemias, and that leukemias with this type of epigenetic alteration might benefit from treatment regimens containing DNA-damaging agents. This study is registered with www.clinicaltrials.gov as NCT00266136.
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Bakshi R, Zaidi SK, Pande S, Hassan MQ, Young DW, Lian JB, van Wijnen AJ, Stein JL, Stein GS. The leukemogenic t(8;21) fusion protein AML1-ETO controls rRNA genes and associates with nucleolar-organizing regions at mitotic chromosomes. J Cell Sci 2008; 121:3981-90. [PMID: 19001502 PMCID: PMC2904240 DOI: 10.1242/jcs.033431] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
RUNX1/AML1 is required for definitive hematopoiesis and is frequently targeted by chromosomal translocations in acute myeloid leukemia (AML). The t(8;21)-related AML1-ETO fusion protein blocks differentiation of myeloid progenitors. Here, we show by immunofluorescence microscopy that during interphase, endogenous AML1-ETO localizes to nuclear microenvironments distinct from those containing native RUNX1/AML1 protein. At mitosis, we clearly detect binding of AML1-ETO to nucleolar-organizing regions in AML-derived Kasumi-1 cells and binding of RUNX1/AML1 to the same regions in Jurkat cells. Both RUNX1/AML1 and AML1-ETO occupy ribosomal DNA repeats during interphase, as well as interact with the endogenous RNA Pol I transcription factor UBF1. Promoter cytosine methylation analysis indicates that RUNX1/AML1 binds to rDNA repeats that are more highly CpG methylated than those bound by AML1-ETO. Downregulation by RNA interference reveals that RUNX1/AML1 negatively regulates rDNA transcription, whereas AML1-ETO is a positive regulator in Kasumi-1 cells. Taken together, our findings identify a novel role for the leukemia-related AML1-ETO protein in epigenetic control of cell growth through upregulation of ribosomal gene transcription mediated by RNA Pol I, consistent with the hyper-proliferative phenotype of myeloid cells in AML patients.
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MESH Headings
- Cell Line, Tumor
- Cell Nucleolus/metabolism
- Chromosomes, Human, Pair 21/genetics
- Chromosomes, Human, Pair 8/genetics
- Core Binding Factor Alpha 2 Subunit/genetics
- Core Binding Factor Alpha 2 Subunit/metabolism
- Fluorescent Antibody Technique
- Genes, rRNA/genetics
- Humans
- Leukemia, Myeloid, Acute/genetics
- Mitosis/genetics
- Nucleolus Organizer Region/metabolism
- Oncogene Proteins, Fusion/genetics
- Oncogene Proteins, Fusion/metabolism
- RUNX1 Translocation Partner 1 Protein
- Translocation, Genetic/genetics
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Affiliation(s)
- Rachit Bakshi
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, MA 01655 USA
| | - Sayyed K. Zaidi
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, MA 01655 USA
| | - Sandhya Pande
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, MA 01655 USA
| | - Mohammad Q. Hassan
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, MA 01655 USA
| | | | - Jane B. Lian
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, MA 01655 USA
| | - Andre J. van Wijnen
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, MA 01655 USA
| | - Janet L. Stein
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, MA 01655 USA
| | - Gary S. Stein
- Department of Cell Biology and Cancer Center, University of Massachusetts Medical School, Worcester, MA 01655 USA
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Gardini A, Cesaroni M, Luzi L, Okumura AJ, Biggs JR, Minardi SP, Venturini E, Zhang DE, Pelicci PG, Alcalay M. AML1/ETO oncoprotein is directed to AML1 binding regions and co-localizes with AML1 and HEB on its targets. PLoS Genet 2008; 4:e1000275. [PMID: 19043539 PMCID: PMC2577924 DOI: 10.1371/journal.pgen.1000275] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2008] [Accepted: 10/22/2008] [Indexed: 11/18/2022] Open
Abstract
A reciprocal translocation involving chromosomes 8 and 21 generates the AML1/ETO oncogenic transcription factor that initiates acute myeloid leukemia by recruiting co-repressor complexes to DNA. AML1/ETO interferes with the function of its wild-type counterpart, AML1, by directly targeting AML1 binding sites. However, transcriptional regulation determined by AML1/ETO probably relies on a more complex network, since the fusion protein has been shown to interact with a number of other transcription factors, in particular E-proteins, and may therefore target other sites on DNA. Genome-wide chromatin immunoprecipitation and expression profiling were exploited to identify AML1/ETO-dependent transcriptional regulation. AML1/ETO was found to co-localize with AML1, demonstrating that the fusion protein follows the binding pattern of the wild-type protein but does not function primarily by displacing it. The DNA binding profile of the E-protein HEB was grossly rearranged upon expression of AML1/ETO, and the fusion protein was found to co-localize with both AML1 and HEB on many of its regulated targets. Furthermore, the level of HEB protein was increased in both primary cells and cell lines expressing AML1/ETO. Our results suggest a major role for the functional interaction of AML1/ETO with AML1 and HEB in transcriptional regulation determined by the fusion protein.
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Affiliation(s)
- Alessandro Gardini
- Department of Experimental Oncology, IEO–European Institute of Oncology, Milan, Italy
| | - Matteo Cesaroni
- Department of Experimental Oncology, IEO–European Institute of Oncology, Milan, Italy
| | - Lucilla Luzi
- IFOM–FIRC Institute for Molecular Oncology Foundation, Milan, Italy
| | - Akiko J. Okumura
- Moores UCSD Cancer Center, Department of Pathology and Division of Biological Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Joseph R. Biggs
- Moores UCSD Cancer Center, Department of Pathology and Division of Biological Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Simone P. Minardi
- IFOM–FIRC Institute for Molecular Oncology Foundation, Milan, Italy
- Cogentech–Consortium for Genomic Technologies, Milan, Italy
| | | | - Dong-Er Zhang
- Moores UCSD Cancer Center, Department of Pathology and Division of Biological Sciences, University of California San Diego, La Jolla, California, United States of America
| | - Pier Giuseppe Pelicci
- Department of Experimental Oncology, IEO–European Institute of Oncology, Milan, Italy
- Dipartimento di Medicina, Chirurgia e Odontoiatria, Università degli Studi di Milano, Milan, Italy
| | - Myriam Alcalay
- Department of Experimental Oncology, IEO–European Institute of Oncology, Milan, Italy
- Cogentech–Consortium for Genomic Technologies, Milan, Italy
- Dipartimento di Medicina, Chirurgia e Odontoiatria, Università degli Studi di Milano, Milan, Italy
- * E-mail:
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Disruption of the NHR4 domain structure in AML1-ETO abrogates SON binding and promotes leukemogenesis. Proc Natl Acad Sci U S A 2008; 105:17103-8. [PMID: 18952841 DOI: 10.1073/pnas.0802696105] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
AML1-ETO is generated from t(8;21)(q22;q22), which is a common form of chromosomal translocation associated with development of acute myeloid leukemia (AML). Although full-length AML1-ETO alone fails to promote leukemia because of its detrimental effects on cell proliferation, an alternatively spliced isoform, AML1-ETO9a, without its C-terminal NHR3/NHR4 domains, strongly induces leukemia. However, full-length AML1-ETO is a major form of fusion product in many t(8;21) AML patients, suggesting additional molecular mechanisms of t(8;21)-related leukemogenesis. Here, we report that disruption of the zinc-chelating structure in the NHR4 domain of AML1-ETO by replacing only one critical amino acid leads to rapid onset of leukemia, demonstrating that the NHR4 domain with the intact structure generates inhibitory effects on leukemogenesis. Furthermore, we identified SON, a DNA/RNA-binding domain containing protein, as a novel NHR4-interacting protein. Knock-down of SON by siRNA resulted in significant growth arrest, and disruption of the interaction between AML1-ETO and endogenous SON rescued cells from AML1-ETO-induced growth arrest, suggesting that SON is an indispensable factor for cell growth, and AML1-ETO binding to SON may trigger signals inhibiting leukemogenesis. In t(8;21) AML patient-derived primary leukemic cells and cell lines, abnormal cytoplasmic localization of SON was detected, which may keep cells proliferating in the presence of full-length AML1-ETO. These results uncovered the crucial role of the NHR4 domain in determination of cellular fate during AML1-ETO-associated leukemogenesis.
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45
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Deletion of Mtg16, a target of t(16;21), alters hematopoietic progenitor cell proliferation and lineage allocation. Mol Cell Biol 2008; 28:6234-47. [PMID: 18710942 DOI: 10.1128/mcb.00404-08] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
While a number of DNA binding transcription factors have been identified that control hematopoietic cell fate decisions, only a limited number of transcriptional corepressors (e.g., the retinoblastoma protein [pRB] and the nuclear hormone corepressor [N-CoR]) have been linked to these functions. Here, we show that the transcriptional corepressor Mtg16 (myeloid translocation gene on chromosome 16), which is targeted by t(16;21) in acute myeloid leukemia, is required for hematopoietic progenitor cell fate decisions and for early progenitor cell proliferation. Inactivation of Mtg16 skewed early myeloid progenitor cells toward the granulocytic/macrophage lineage while reducing the numbers of megakaryocyte-erythroid progenitor cells. In addition, inactivation of Mtg16 impaired the rapid expansion of short-term stem cells, multipotent progenitor cells, and megakaryocyte-erythroid progenitor cells that is required under hematopoietic stress/emergency. This impairment appears to be a failure to proliferate rather than an induction of cell death, as expression of c-Myc, but not Bcl2, complemented the Mtg16(-/-) defect.
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46
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Zhang J, Wilkinson JE, Gonit M, Keck R, Selman S, Ratnam M. Expression and sub-cellular localization of the CCAAT/enhancer binding protein alpha in relation to postnatal development and malignancy of the prostate. Prostate 2008; 68:1206-14. [PMID: 18481268 PMCID: PMC3911780 DOI: 10.1002/pros.20779] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
BACKGROUND C/EBPalpha is a critical mediator of terminal differentiation and a tumor suppressor through its strong antiproliferative actions on cell cycle regulatory proteins. C/EBPalpha also appears to regulate androgen receptor (AR) AR signaling. There, is a paucity of information on the expression and sub-cellular localization of C/EBPalpha in normal mouse and human prostate and in prostate cancer. METHODS Immunohistochemistry of tissues including tissue arrays, quantitative polymerase chain reaction and mRNA expression database mining. RESULTS In the mouse prostate epithelium, C/EBPalpha was present at 1 week postnatal localized in the cytosol, began to show nuclear localization at 8 weeks and continued to show prominent nuclear expression at 10 weeks and beyond; C/EBPalpha mRNA was expressed at all ages. In humans, C/EBPalpha showed prominent nuclear localization from peripubescence up to middle age but was sequestered in the cytosol in older individuals; the mRNA level for C/EBPalpha remained essentially unchanged. Most prostate adenocarcinomas expressed a range of levels of C/EBPalpha mRNA and protein that were relatively high in metastatic tumors in a manner that correlated with AR expression; however, most cells showed C/EBPalpha sequestered in the cytosol. CONCLUSIONS Temporal changes in sub-cellular localization of C/EBPalpha are consistent with a role in prostate differentiation and as a prostate tumor suppressor; the cytoplasmic sequestration of C/EBPalpha, unique to older human prostates, is arguably a permissive condition for the greater frequency of proliferative disorders of the prostate. In malignant prostate C/EBPalpha may be available to regulate AR signaling through transient changes in its sub-cellular localization.
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Affiliation(s)
- Juan Zhang
- Department of Biochemistry and Cancer Biology, Medical University of Ohio, Toledo, Ohio
| | - John Erby Wilkinson
- Department of Pathology, University of Michigan School of Medicine, Ann Arbor, Michigan
| | - Mesfin Gonit
- Department of Biochemistry and Cancer Biology, Medical University of Ohio, Toledo, Ohio
| | - Rick Keck
- Department of Urology, Medical University of Ohio, Toledo, Ohio
| | - Steven Selman
- Department of Urology, Medical University of Ohio, Toledo, Ohio
| | - Manohar Ratnam
- Department of Biochemistry and Cancer Biology, Medical University of Ohio, Toledo, Ohio
- Correspondence to: Prof. Manohar Ratnam, 3000 Arlington Avenue, Toledo, OH 43614.
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Müller AMS, Duque J, Shizuru JA, Lübbert M. Complementing mutations in core binding factor leukemias: from mouse models to clinical applications. Oncogene 2008; 27:5759-73. [PMID: 18604246 DOI: 10.1038/onc.2008.196] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
A great proportion of acute myeloid leukemias (AMLs) display cytogenetic abnormalities including chromosomal aberrations and/or submicroscopic mutations. These abnormalities significantly influence the prognosis of the disease. Hence, a thorough genetic work-up is an essential constituent of standard diagnostic procedures. Core binding factor (CBF) leukemias denote AMLs with chromosomal aberrations disrupting one of the CBF transcription factor genes; the most common examples are translocation t(8;21) and inversion inv(16), which result in the generation of the AML1-ETO and CBFbeta-MYH11 fusion proteins, respectively. However, in murine models, these alterations alone do not suffice to generate full-blown leukemia, but rather, complementary events are required. In fact, a substantial proportion of primary CBF leukemias display additional activating mutations, mostly of the receptor tyrosine kinase (RTK) c-KIT. The awareness of the impact and prognostic relevance of these 'second hits' is increasing with a wider range of mutations tested in clinical trials. Furthermore, novel agents targeting RTKs are emanating rapidly and entering therapeutic regimens. Here, we present a concise review on complementing mutations in CBF leukemias including pathophysiology, mouse models, and clinical implications.
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Affiliation(s)
- A M S Müller
- Department of Hematology/Oncology, University Medical Center Freiburg, Baden Wuerttemberg, Freiburg, Germany
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48
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Ko RM, Kim HG, Wolff L, Klug CA. Roles of p15Ink4b and p16Ink4a in myeloid differentiation and RUNX1-ETO-associated acute myeloid leukemia. Leuk Res 2008; 32:1101-11. [PMID: 18037485 PMCID: PMC2430055 DOI: 10.1016/j.leukres.2007.10.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2007] [Revised: 10/10/2007] [Accepted: 10/16/2007] [Indexed: 10/22/2022]
Abstract
Inactivation of p15(Ink4b) expression by promoter hypermethylation occurs in up to 80% of acute myeloid leukemia (AML) cases and is particularly common in the FAB-M2 subtype of AML, which is characterized by the presence of the RUNX1-ETO translocation in 40% of cases. To establish whether the loss of p15(Ink4b) contributes to AML progression in association with RUNX1-ETO, we have expressed the RUNX1-ETO fusion protein from a retroviral vector in hematopoietic progenitor cells isolated from wild-type, p15(Ink4b) or p16(Ink4a) knockout bone marrow. Analysis of lethally irradiated recipient mice reconstituted with RUNX1-ETO-expressing cells showed that neither p15(Ink4b) or p16(Ink4a) loss significantly accelerated disease progression over the time period of one year post-transplantation. Loss of p15(Ink4b) alone resulted in increased myeloid progenitor cell frequencies in bone marrow by 10-month post-transplant and a 19-fold increase in the frequency of Lin(-)c-Kit(+)Sca-1(+) (LKS) cells that was not associated with expansion of long-term reconstituting HSC. These results strongly suggest that p15(Ink4b) loss must be accompanied by additional oncogenic changes for RUNX1-ETO-associated AML to develop.
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Affiliation(s)
- Rose M. Ko
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, Birmingham, AL
| | - Hyung-Gyoon Kim
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL
| | - Linda Wolff
- Center for Cancer Research, National Cancer Institute, NIH, Bethesda, MD
| | - Christopher A. Klug
- Department of Biochemistry and Molecular Genetics, The University of Alabama at Birmingham, Birmingham, AL
- Department of Microbiology, The University of Alabama at Birmingham, Birmingham, AL
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AML1-ETO interacts with Sp1 and antagonizes Sp1 transactivity through RUNT domain. FEBS Lett 2008; 582:2167-72. [PMID: 18519037 DOI: 10.1016/j.febslet.2008.05.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2008] [Revised: 05/16/2008] [Accepted: 05/20/2008] [Indexed: 11/22/2022]
Abstract
AML1-ETO fusion protein is observed in approximately 12% of acute myeloid leukemia. In the present research, we found that AML1-ETO is able to inhibit Sp1 transactivity. We also found that this inhibition of Sp1 transactivity by AML1-ETO is achieved by interaction between Sp1 and RUNT domain of AML1. AML1b is able to abrogate the inhibition of AML1-ETO. Since Sp1 is involved in hematopoietic cell differentiation, we proposed that AML1-ETO promotes leukemogenesis by blocking cell differentiation through inhibition of Sp1 transactivity.
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50
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Serrano E, Carnicer MJ, Lasa A, Orantes V, Pena J, Brunet S, Aventín A, Sierra J, Nomdedéu JF. Epigenetic-based treatments emphasize the biologic differences of core-binding factor acute myeloid leukemias. Leuk Res 2008; 32:944-53. [DOI: 10.1016/j.leukres.2007.11.038] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2007] [Revised: 11/14/2007] [Accepted: 11/24/2007] [Indexed: 10/22/2022]
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