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Nwabo Kamdje AH, Dongmo Fogang HP, Mimche PN. Role of epigenetic in cancer biology, in hematologic malignancies and in anticancer therapy. FRONTIERS IN MOLECULAR MEDICINE 2024; 4:1426454. [PMID: 39308891 PMCID: PMC11412843 DOI: 10.3389/fmmed.2024.1426454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/01/2024] [Accepted: 08/08/2024] [Indexed: 09/25/2024]
Abstract
Major epigenetic changes are associated with carcinogenesis, including aberrant DNA methylations and post-translational modifications of histone. Indeed evidence accumulated in recent years indicates that inactivating DNA hypermethylation preferentially targets the subset of polycomb group (PcG) genes that are regulators of developmental processes. Conversely, activating DNA hypomethylation targets oncogenic signaling pathway genes, but outcomes of both events lead in the overexpression of oncogenic signaling pathways that contribute to the stem-like state of cancer cells. On the basis of recent evidence from population-basedclinical and experimental studies, we hypothesize that factors associated with risk for developing a hematologic malignancy (HM), such as metabolic syndrome and chronic inflammation, may trigger epigenetic mechanisms to increase the transcriptional expression of oncogenes and activate oncogenic signaling pathways. Signaling pathways associated with such risk factors include but are not limited to pro-inflammatory nuclear factor κB (NF-κB) and mitogenic, growth, and survival Janus kinase (JAK) intracellular non-receptor tyrosine kinase-triggered pathways. The latter includes signaling pathways such as transducer and activator of transcription (STAT), Ras GTPases/mitogen-activated protein kinases (MAPKs)/extracellular signal-related kinases (ERKs), phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR), and β-catenin pathways. Recent findings on epigenetic mechanisms at work in the biology of cancer and in HMs and their importance in the etiology and pathogenesis of these diseases are herein summarized and discussed. Furthermore, the role of epigenetic processes in the determination of biological identity, the consequences for interindividual variability in disease clinical profile, and the potential of epigenetic drugs in HMs are also considered.
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Affiliation(s)
- Armel Hervé Nwabo Kamdje
- Department of Physiological Sciences and Biochemistry, Faculty of Medicine and Biomedical Sciences, University of Garoua, Garoua, Cameroon
| | - Hervet Paulain Dongmo Fogang
- Department of Physiological Sciences and Biochemistry, Faculty of Medicine and Biomedical Sciences, University of Garoua, Garoua, Cameroon
| | - Patrice N. Mimche
- Department of Dermatology, Indiana University School of Medicine, Indianapolis, IN, United States
- Department of Medicine, Division of Gastroenterology and Hepatology, Indiana University School of Medicine, Indianapolis, IN, United States
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Shi Q, Xue C, Zeng Y, Yuan X, Chu Q, Jiang S, Wang J, Zhang Y, Zhu D, Li L. Notch signaling pathway in cancer: from mechanistic insights to targeted therapies. Signal Transduct Target Ther 2024; 9:128. [PMID: 38797752 PMCID: PMC11128457 DOI: 10.1038/s41392-024-01828-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2024] [Revised: 03/31/2024] [Accepted: 04/15/2024] [Indexed: 05/29/2024] Open
Abstract
Notch signaling, renowned for its role in regulating cell fate, organ development, and tissue homeostasis across metazoans, is highly conserved throughout evolution. The Notch receptor and its ligands are transmembrane proteins containing epidermal growth factor-like repeat sequences, typically necessitating receptor-ligand interaction to initiate classical Notch signaling transduction. Accumulating evidence indicates that the Notch signaling pathway serves as both an oncogenic factor and a tumor suppressor in various cancer types. Dysregulation of this pathway promotes epithelial-mesenchymal transition and angiogenesis in malignancies, closely linked to cancer proliferation, invasion, and metastasis. Furthermore, the Notch signaling pathway contributes to maintaining stem-like properties in cancer cells, thereby enhancing cancer invasiveness. The regulatory role of the Notch signaling pathway in cancer metabolic reprogramming and the tumor microenvironment suggests its pivotal involvement in balancing oncogenic and tumor suppressive effects. Moreover, the Notch signaling pathway is implicated in conferring chemoresistance to tumor cells. Therefore, a comprehensive understanding of these biological processes is crucial for developing innovative therapeutic strategies targeting Notch signaling. This review focuses on the research progress of the Notch signaling pathway in cancers, providing in-depth insights into the potential mechanisms of Notch signaling regulation in the occurrence and progression of cancer. Additionally, the review summarizes pharmaceutical clinical trials targeting Notch signaling for cancer therapy, aiming to offer new insights into therapeutic strategies for human malignancies.
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Affiliation(s)
- Qingmiao Shi
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Chen Xue
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Yifan Zeng
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Xin Yuan
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Qingfei Chu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Shuwen Jiang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Jinzhi Wang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Yaqi Zhang
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China
| | - Danhua Zhu
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China.
| | - Lanjuan Li
- State Key Laboratory for Diagnosis and Treatment of Infectious Diseases, National Clinical Research Center for Infectious Diseases, National Medical Center for Infectious Diseases, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, The First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310003, China.
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Kastner P, Chan S. IKAROS Family Transcription Factors in Lymphocyte Differentiation and Function. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2024; 1459:33-52. [PMID: 39017838 DOI: 10.1007/978-3-031-62731-6_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2024]
Abstract
The IKAROS family of transcription factors comprises four zinc-finger proteins (IKAROS, HELIOS, AIOLOS, and EOS), which over the last decades have been established to be critical regulators of the development and function of lymphoid cells. These factors act as homo- or heterodimers and are involved both in gene activation and repression. Their function often involves cross-talk with other regulatory circuits, such as the JAK/STAT, NF-κB, and NOTCH pathways. They control lymphocyte differentiation at multiple stages and are notably critical for lymphoid commitment in multipotent hematopoietic progenitors and for T and B cell differentiation downstream of pre-TCR and pre-BCR signaling. They also control many aspects of effector functions in mature B and T cells. They are dysregulated or mutated in multiple pathologies affecting the lymphoid system, which range from leukemia to immunodeficiencies. In this chapter, we review the molecular and physiological function of these factors in lymphocytes and their implications in human pathologies.
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Affiliation(s)
- Philippe Kastner
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch-Graffenstaden, France.
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch-Graffenstaden, France.
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch-Graffenstaden, France.
- Université de Strasbourg, Illkirch-Graffenstaden, France.
- Faculté de Médecine, Université de Strasbourg, Strasbourg, France.
| | - Susan Chan
- Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), Illkirch-Graffenstaden, France.
- Institut National de la Santé et de la Recherche Médicale (INSERM), U1258, Illkirch-Graffenstaden, France.
- Centre National de la Recherche Scientifique (CNRS), UMR7104, Illkirch-Graffenstaden, France.
- Université de Strasbourg, Illkirch-Graffenstaden, France.
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IL-15 Prevents the Development of T-ALL from Aberrant Thymocytes with Impaired DNA Repair Functions and Increased NOTCH1 Activation. Cancers (Basel) 2023; 15:cancers15030671. [PMID: 36765626 PMCID: PMC9913776 DOI: 10.3390/cancers15030671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/16/2023] [Accepted: 01/18/2023] [Indexed: 01/25/2023] Open
Abstract
We previously reported that NOD.Scid mice lacking interleukin-15 (IL-15), or IL-15 receptor alpha-chain, develop T-acute lymphoblastic leukemia (T-ALL). To understand the mechanisms by which IL-15 signaling controls T-ALL development, we studied the thymocyte developmental events in IL-15-deficient Scid mice from NOD and C57BL/6 genetic backgrounds. Both kinds of mice develop T-ALL characterized by circulating TCR-negative cells expressing CD4, CD8 or both. Analyses of thymocytes in NOD.Scid.Il15-/- mice prior to T-ALL development revealed discernible changes within the CD4-CD8- double-negative (DN) thymocyte developmental stages and increased frequencies of CD4+CD8+ double-positive cells with a high proportion of TCR-negative CD4+ and CD8+ cells. The DN cells also showed elevated expressions of CXCR4 and CD117, molecules implicated in the expansion of DN thymocytes. T-ALL cell lines and primary leukemic cells from IL-15-deficient NOD.Scid and C57BL/6.Scid mice displayed increased NOTCH1 activation that was inhibited by NOTCH1 inhibitors and blockers of the PI3K/AKT pathway. Primary leukemic cells from NOD.Scid.Il15-/- mice survived and expanded when cultured with MS5 thymic stromal cells expressing Delta-like ligand 4 and supplemented with IL-7 and FLT3 ligand. These findings suggest that IL-15 signaling in the thymus controls T-ALL development from aberrant thymocytes with an impaired DNA repair capacity and increased NOTCH1 activation.
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Kashiwagi M, Figueroa DS, Ay F, Morgan BA, Georgopoulos K. A double-negative thymocyte-specific enhancer augments Notch1 signaling to direct early T cell progenitor expansion, lineage restriction and β-selection. Nat Immunol 2022; 23:1628-1643. [PMID: 36316479 PMCID: PMC10187983 DOI: 10.1038/s41590-022-01322-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 09/06/2022] [Indexed: 11/11/2022]
Abstract
T cell differentiation requires Notch1 signaling. In the present study, we show that an enhancer upstream of Notch1 active in double-negative (DN) mouse thymocytes is responsible for raising Notch1 signaling intrathymically. This enhancer is required to expand multipotent progenitors intrathymically while delaying early differentiation until lineage restrictions have been established. Early thymic progenitors lacking the enhancer show accelerated differentiation through the DN stages and increased frequency of B, innate lymphoid (IL) and natural killer (NK) cell differentiation. Transcription regulators for T cell lineage restriction and commitment are expressed normally, but IL and NK cell gene expression persists after T cell lineage commitment and T cell receptor β VDJ recombination, Cd3 expression and β-selection have been impaired. This Notch1 enhancer is inactive in double-positive (DP) thymocytes. Its aberrant reactivation at this stage in Ikaros mutants is required for leukemogenesis. Thus, the DN-specific Notch1 enhancer harnesses the regulatory architecture of DN and DP thymocytes to achieve carefully orchestrated changes in Notch1 signaling required for early lineage restrictions and normal T cell differentiation.
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Parriott G, Kee BL. E Protein Transcription Factors as Suppressors of T Lymphocyte Acute Lymphoblastic Leukemia. Front Immunol 2022; 13:885144. [PMID: 35514954 PMCID: PMC9065262 DOI: 10.3389/fimmu.2022.885144] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Accepted: 03/23/2022] [Indexed: 11/13/2022] Open
Abstract
T Lymphocyte Acute Lymphoblastic Leukemia (ALL) is an aggressive disease arising from transformation of T lymphocytes during their development. The mutation spectrum of T-ALL has revealed critical regulators of the growth and differentiation of normal and leukemic T lymphocytes. Approximately, 60% of T-ALLs show aberrant expression of the hematopoietic stem cell-associated helix-loop-helix transcription factors TAL1 and LYL1. TAL1 and LYL1 function in multiprotein complexes that regulate gene expression in T-ALL but they also antagonize the function of the E protein homodimers that are critical regulators of T cell development. Mice lacking E2A, or ectopically expressing TAL1, LYL1, or other inhibitors of E protein function in T cell progenitors, also succumb to an aggressive T-ALL-like disease highlighting that E proteins promote T cell development and suppress leukemogenesis. In this review, we discuss the role of E2A in T cell development and how alterations in E protein function underlie leukemogenesis. We focus on the role of TAL1 and LYL1 and the genes that are dysregulated in E2a-/- T cell progenitors that contribute to human T-ALL. These studies reveal novel mechanisms of transformation and provide insights into potential therapeutic targets for intervention in this disease.
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Affiliation(s)
- Geoffrey Parriott
- Committee on Immunology, University of Chicago, Chicago, IL, United States
| | - Barbara L Kee
- Committee on Immunology, University of Chicago, Chicago, IL, United States.,Committee on Cancer Biology, University of Chicago, Chicago, IL, United States.,Department of Pathology, University of Chicago, Chicago, IL, United States
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Carr T, McGregor S, Dias S, Verykokakis M, Le Beau MM, Xue HH, Sigvardsson M, Bartom ET, Kee BL. Oncogenic and Tumor Suppressor Functions for Lymphoid Enhancer Factor 1 in E2a-/- T Acute Lymphoblastic Leukemia. Front Immunol 2022; 13:845488. [PMID: 35371057 PMCID: PMC8971981 DOI: 10.3389/fimmu.2022.845488] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2021] [Accepted: 02/23/2022] [Indexed: 11/15/2022] Open
Abstract
T lymphocyte acute lymphoblastic leukemia (T-ALL) is a heterogeneous disease affecting T cells at multiple stages of their development and is characterized by frequent genomic alterations. The transcription factor LEF1 is inactivated through mutation in a subset of T-ALL cases but elevated LEF1 expression and activating mutations have also been identified in this disease. Here we show, in a murine model of T-ALL arising due to E2a inactivation, that the developmental timing of Lef1 mutation impacts its ability to function as a cooperative tumor suppressor or oncogene. T cell transformation in the presence of LEF1 allows leukemic cells to become addicted to its presence. In contrast, deletion prior to transformation both accelerates leukemogenesis and results in leukemic cells with altered expression of genes controlling receptor-signaling pathways. Our data demonstrate that the developmental timing of Lef1 mutations impact its apparent oncogenic or tumor suppressive characteristics and demonstrate the utility of mouse models for understanding the cooperation and consequence of mutational order in leukemogenesis.
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Affiliation(s)
- Tiffany Carr
- Committee on Immunology, The University of Chicago, Chicago, IL, United States
| | - Stephanie McGregor
- Committee on Cancer Biology, The University of Chicago, Chicago, IL, United States
| | - Sheila Dias
- Department of Pathology, The University of Chicago, Chicago, Chicago, IL, United States
| | - Mihalis Verykokakis
- Department of Pathology, The University of Chicago, Chicago, Chicago, IL, United States
| | - Michelle M. Le Beau
- Department of Medicine, Section of Hematology/Oncology, The University of Chicago, Chicago, IL, United States
| | - Hai-Hui Xue
- Center for Discovery and Innovation, Hackensack University Medical Center, Nutley, NJ, United States
| | | | - Elizabeth T. Bartom
- Department of Biochemistry and Molecular Genetics, Northwestern University, Chicago, IL, United States
| | - Barbara L. Kee
- Committee on Immunology, The University of Chicago, Chicago, IL, United States
- Committee on Cancer Biology, The University of Chicago, Chicago, IL, United States
- Department of Pathology, The University of Chicago, Chicago, Chicago, IL, United States
- *Correspondence: Barbara L. Kee,
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Sun W, Song X, Dong M, Liu Z, Song Y, Wang L, Song L. DNA binding protein CgIkaros-like regulates the proliferation of agranulocytes and granulocytes in oyster (Crassostrea gigas). DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2021; 124:104201. [PMID: 34252475 DOI: 10.1016/j.dci.2021.104201] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Revised: 07/04/2021] [Accepted: 07/07/2021] [Indexed: 06/13/2023]
Abstract
DNA-binding protein Ikaros is a major determinant of haematopoietic lineage, especially in the development, differentiation and proliferation of lymphocytes. In the present study, a Ikaros homologue (designed as CgIkaros-like) was identified and characterized as a vital determinant in the proliferation of haemocytes during haematopoiesis of Pacific oyster Crassostrea gigas. The complete coding sequence of CgIkaros-like was of 1329 bp encoding a predicted polypeptide of 442 amino acids with four ZnF regions, locating at the C-terminus and N-terminus respectively. The highest expression level of CgIkaros-like mRNA was found in gills, followed by haemocytes and gonad. The mRNA transcripts of CgIkaros-like could be detected in all the haemocytes with higher abundance in semi-granulocytes and agranulocytes. CgIkaros-like protein was localized in both of cytoplasm and nucleus with higher abundance in nucleus of oyster haemocytes. The mRNA and protein expression levels of agranulocyte marker CgCD9, granulocyte marker CgAATase, cell cycle related gene CgCDK2, Notch receptor CgNotch and Notch target gene CgHes1 all increased significantly (p < 0.05) after CgIkaros-like was interfered by siRNAs, which were about 27.33-, 2.63-, 24.34-, 4.45- and 6.08-fold of that in the siRNA-NC control group, respectively. While the transcripts of CgGATA3 and CgRunx did not change significantly after CgIkaros-like was interfered. These results demonstrated that CgIkaros-like functioned as a transcription factor combined with Notch pathway to mediate CgCDK2 and regulate the proliferation of oyster haemocytes.
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Affiliation(s)
- Wending Sun
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China
| | - Xiaorui Song
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China
| | - Miren Dong
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China
| | - Zhuyun Liu
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China
| | - Ying Song
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China
| | - Lingling Wang
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Liaoning Key Laboratory of Marine Animal Immunology and Disease Control, Dalian Ocean University, Dalian, 116023, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China
| | - Linsheng Song
- Liaoning Key Laboratory of Marine Animal Immunology, Dalian Ocean University, Dalian, 116023, China; Southern Marine Science and Engineering Guangdong Laboratory, Zhuhai, 519000, China; Functional Laboratory of Marine Fisheries Science and Food Production Processes, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266235, China; Dalian Key Laboratory of Aquatic Animal Disease Prevention and Control, Dalian Ocean University, Dalian, 116023, China.
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Ferreira A, Aster JC. Notch signaling in cancer: Complexity and challenges on the path to clinical translation. Semin Cancer Biol 2021; 85:95-106. [PMID: 33862222 DOI: 10.1016/j.semcancer.2021.04.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2021] [Revised: 03/29/2021] [Accepted: 04/11/2021] [Indexed: 12/22/2022]
Abstract
Notch receptors participate in a conserved pathway in which ligands expressed on neighboring cells trigger a series of proteolytic cleavages that allow the intracellular portion of the receptor to travel to the nucleus and form a short-lived transcription complex that turns on target gene expression. The directness and seeming simplicity of this signaling mechanism belies the complexity of the outcomes of Notch signaling in normal cells, which are highly context and dosage dependent. This complexity is reflected in the diverse roles of Notch in cancers of various types, in which Notch may be oncogenic or tumor suppressive and may have a wide spectrum of effects on tumor cells and stromal elements. This review provides an overview of the roles of Notch in cancer and discusses challenges to clinical translation of Notch targeting agents as well as approaches that may overcome these hurdles.
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Affiliation(s)
- Antonio Ferreira
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA, 02115, United States
| | - Jon C Aster
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, 75 Francis Street, Boston, MA, 02115, United States.
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Lemarié M, Bottardi S, Mavoungou L, Pak H, Milot E. IKAROS is required for the measured response of NOTCH target genes upon external NOTCH signaling. PLoS Genet 2021; 17:e1009478. [PMID: 33770102 PMCID: PMC8026084 DOI: 10.1371/journal.pgen.1009478] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 04/07/2021] [Accepted: 03/08/2021] [Indexed: 12/16/2022] Open
Abstract
The tumor suppressor IKAROS binds and represses multiple NOTCH target genes. For their induction upon NOTCH signaling, IKAROS is removed and replaced by NOTCH Intracellular Domain (NICD)-associated proteins. However, IKAROS remains associated to other NOTCH activated genes upon signaling and induction. Whether IKAROS could participate to the induction of this second group of NOTCH activated genes is unknown. We analyzed the combined effect of IKAROS abrogation and NOTCH signaling on the expression of NOTCH activated genes in erythroid cells. In IKAROS-deleted cells, we observed that many of these genes were either overexpressed or no longer responsive to NOTCH signaling. IKAROS is then required for the organization of bivalent chromatin and poised transcription of NOTCH activated genes belonging to either of the aforementioned groups. Furthermore, we show that IKAROS-dependent poised organization of the NOTCH target Cdkn1a is also required for its adequate induction upon genotoxic insults. These results highlight the critical role played by IKAROS in establishing bivalent chromatin and transcriptional poised state at target genes for their activation by NOTCH or other stress signals. NOTCH1 deregulation can favor hematological malignancies. In addition to RBP-Jκ/NICD/MAML1, other regulators are required for the measured activation of NOTCH target genes. IKAROS is a known repressor of many NOTCH targets. Since it can also favor transcriptional activation and control gene expression levels, we questioned whether IKAROS could participate to the activation of specific NOTCH target genes. We are reporting that upon NOTCH induction, the absence of IKAROS impairs the measured activation of two groups of NOTCH target genes: (i) those overexpressed and characterized by an additive effect imposed by the absence of IKAROS and NOTCH induction; and (ii) those ‘desensitized’ and no more activated by NOTCH. At genes of both groups, IKAROS controls the timely recruitment of the chromatin remodelers CHD4 and BRG1. IKAROS then influences the activation of these genes through the organization of chromatin and poised transcription or through transcriptional elongation control. The importance of the IKAROS controlled and measured activation of genes is not limited to NOTCH signaling as it also characterizes Cdkn1a expression upon genotoxic stress. Thus, these results provide a new perspective on the importance of IKAROS for the adequate cellular response to stress, whether imposed by NOTCH or genotoxic insults.
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Affiliation(s)
- Maud Lemarié
- Maisonneuve-Rosemont Hospital Research Center; CIUSSS de l’est de l’Île de Montréal, Montréal, QC, Canada
- Department of Medicine, Université de Montréal, Montréal, Québec, Canada
| | - Stefania Bottardi
- Maisonneuve-Rosemont Hospital Research Center; CIUSSS de l’est de l’Île de Montréal, Montréal, QC, Canada
| | - Lionel Mavoungou
- Maisonneuve-Rosemont Hospital Research Center; CIUSSS de l’est de l’Île de Montréal, Montréal, QC, Canada
| | - Helen Pak
- Maisonneuve-Rosemont Hospital Research Center; CIUSSS de l’est de l’Île de Montréal, Montréal, QC, Canada
| | - Eric Milot
- Maisonneuve-Rosemont Hospital Research Center; CIUSSS de l’est de l’Île de Montréal, Montréal, QC, Canada
- Department of Medicine, Université de Montréal, Montréal, Québec, Canada
- * E-mail:
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Tillman H, Janke LJ, Funk A, Vogel P, Rehg JE. Morphologic and Immunohistochemical Characterization of Spontaneous Lymphoma/Leukemia in NSG Mice. Vet Pathol 2019; 57:160-171. [PMID: 31736441 DOI: 10.1177/0300985819882631] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ strain (NOD scid gamma, NSG) is a severely immunodeficient inbred laboratory mouse used for preclinical studies because it is amenable to engraftment with human cells. Combining scid and Il2rgnull mutations results in severe immunodeficiency by impairing the maturation, survival, and functionality of interleukin 2-dependent immune cells, including T, B, and natural killer lymphocytes. While NSG mice are reportedly resistant to developing spontaneous lymphomas/leukemias, there are reports of hematopoietic cancers developing. In this study, we characterized the immunophenotype of spontaneous lymphoma/leukemia in 12 NSG mice (20 to 38 weeks old). The mice had a combination of grossly enlarged thymus, spleen, or lymph nodes and variable histologic involvement of the bone marrow and other tissues. All 12 lymphomas were diffusely CD3, TDT, and CD4 positive, and 11 of 12 were also positive for CD8, which together was consistent with precursor T-cell lymphoblastic lymphoma/leukemia (pre-T-LBL). A subset of NSG tissues from all mice and neoplastic lymphocytes from 8 of 12 cases had strong immunoreactivity for retroviral p30 core protein, suggesting an association with a viral infection. These data highlight that NSG mice may develop T-cell lymphoma at low frequency, necessitating the recognition of this spontaneously arising disease when interpreting studies.
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Affiliation(s)
- Heather Tillman
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Laura J Janke
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Amy Funk
- Animal Resources Center, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Peter Vogel
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN, USA
| | - Jerold E Rehg
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, TN, USA
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12
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Huang BJ, Wandler AM, Meyer LK, Dail M, Daemen A, Sampath D, Li Q, Wang X, Wong JC, Nakitandwe J, Downing JR, Zhang J, Taylor BS, Shannon K. Convergent genetic aberrations in murine and human T lineage acute lymphoblastic leukemias. PLoS Genet 2019; 15:e1008168. [PMID: 31199785 PMCID: PMC6594654 DOI: 10.1371/journal.pgen.1008168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 06/26/2019] [Accepted: 04/29/2019] [Indexed: 12/22/2022] Open
Abstract
The lack of predictive preclinical models is a fundamental barrier to translating knowledge about the molecular pathogenesis of cancer into improved therapies. Insertional mutagenesis (IM) in mice is a robust strategy for generating malignancies that recapitulate the extensive inter- and intra-tumoral genetic heterogeneity found in advanced human cancers. While the central role of "driver" viral insertions in IM models that aberrantly increase the expression of proto-oncogenes or disrupt tumor suppressors has been appreciated for many years, the contributions of cooperating somatic mutations and large chromosomal alterations to tumorigenesis are largely unknown. Integrated genomic studies of T lineage acute lymphoblastic leukemias (T-ALLs) generated by IM in wild-type (WT) and Kras mutant mice reveal frequent point mutations and other recurrent non-insertional genetic alterations that also occur in human T-ALL. These somatic mutations are sensitive and specific markers for defining clonal dynamics and identifying candidate resistance mechanisms in leukemias that relapse after an initial therapeutic response. Primary cancers initiated by IM and resistant clones that emerge during in vivo treatment close key gaps in existing preclinical models, and are robust platforms for investigating the efficacy of new therapies and for elucidating how drug exposure shapes tumor evolution and patterns of resistance. A lack of predictive cancer models is a major bottleneck for prioritizing new anti-cancer drugs for clinical trials. We comprehensively profiled a panel of primary mouse T lineage leukemias initiated by insertional mutagenesis and found remarkable similarities with human T-ALL in regard to overall mutational burden, the occurrence of specific somatic mutations and large chromosomal alterations, and concordant gene expression signatures. We observed frequent duplication of the Kras oncogene with loss of the normal allele, which has potential therapeutic implications that merit further investigation in human leukemia and in other preclinical models. Mutations identified in mouse leukemias that relapsed after in vivo treatment with signal transduction inhibitors were also observed in relapsed human T-ALL, indicating that this model system can be utilized to investigate strategies for overcoming intrinsic and acquired drug resistance. Finally, preclinical models similar to the one described here that are characterized by a normal endogenous tumor microenvironment and intact immune system will become increasingly important for testing immunotherapy approaches for human cancer.
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Affiliation(s)
- Benjamin J. Huang
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, United States of America
| | - Anica M. Wandler
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, United States of America
| | - Lauren K. Meyer
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, United States of America
| | - Monique Dail
- Department of Oncology Biomarker Development, Genentech, South San Francisco, CA, United States of America
| | - Anneleen Daemen
- Department of Bioinformatics & Computational Biology, Genentech, South San Francisco, CA, United States of America
| | - Deepak Sampath
- Department of Translational Oncology, Genentech, South San Francisco, CA, United States of America
| | - Qing Li
- Division of Hematology/Oncology, Department of Medicine, University of Michigan, Ann Arbor, MI, United States of America
| | - Xinyue Wang
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, United States of America
| | - Jasmine C. Wong
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, United States of America
| | - Joy Nakitandwe
- Department of Pathology, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - James R. Downing
- Department of Pathology, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Jinghui Zhang
- Department of Computational Biology, St Jude Children’s Research Hospital, Memphis, Tennessee, United States of America
| | - Barry S. Taylor
- Marie-Josée and Henry R. Kravis Center for Molecular Oncology, Memorial Sloan Kettering Cancer Center, New York, NY, United States of America
- Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY, United States of America
- Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, United States of America
| | - Kevin Shannon
- Department of Pediatrics, University of California San Francisco, San Francisco, CA, United States of America
- Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA, United States of America
- * E-mail:
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13
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Yi L, Hu Q, Zhou J, Liu Z, Li H. Alternative splicing of Ikaros regulates the FUT4/Le X-α5β1 integrin-FAK axis in acute lymphoblastic leukemia. Biochem Biophys Res Commun 2019; 510:128-134. [PMID: 30683310 DOI: 10.1016/j.bbrc.2019.01.064] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 01/12/2019] [Indexed: 12/24/2022]
Abstract
Unveiling the mechanism of the relapse of acute lymphoblastic leukemia (ALL) is the key to improve the prognosis of ALL and remains a huge challenge. Glycan-based interactions play a vital role in immune surveillance, cell-cell adhesion and cell-matrix interaction, contributing to treatment failure in tumor. However, the glycan essential for leukemia development and its upstream regulatory mechanism by oncogenic drivers were rarely reported. Here, we demonstrated that LeX, a well-characterized cancer-related glycan epitope, strengthened the cell-matrix interaction via glycosylating α5β1 integrin under the control of the driver oncogenic Ikaros isoform (IK6) in ALL. By analyzing the expression profile of Ikaros and the level of FUT4/LeX in clinical samples, we found that FUT4/LeX was positively correlated with dysfunctional Ikaros isoforms. IK1 (Full length Ikaros) regulates the level of FUT4 as a transcription repressor, while IK6 abolished the wild-type Ikaros mediated transcriptional repression and resulted in higher level of FUT4 expression. Moreover, we demonstrated that FUT4 could activate α5β1-mediated sequential signal transduction and accelerate adhesion and invasion between integrin α5β1 in leukemia cells and fibronectin in extracellular matrix (ECM) via increasing glycosylation. Together, our study provides a new insight into the mechanisms by which Ikaros mutation induced ALL cells invasion and a potential strategy for drug-resistance ALL by blocking LeX in combination with common chemotherapy.
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Affiliation(s)
- Lijun Yi
- Central Laboratory, Jiangxi Provincial Children's Hospital, Yangming Rd, Nanchang, Jiangxi, 330006, China
| | - Qinghua Hu
- Central Laboratory, Jiangxi Provincial Children's Hospital, Yangming Rd, Nanchang, Jiangxi, 330006, China
| | - Jing Zhou
- Central Laboratory, Jiangxi Provincial Children's Hospital, Yangming Rd, Nanchang, Jiangxi, 330006, China
| | - Zhiqiang Liu
- Central Laboratory, Jiangxi Provincial Children's Hospital, Yangming Rd, Nanchang, Jiangxi, 330006, China
| | - Hong Li
- Central Laboratory, Jiangxi Provincial Children's Hospital, Yangming Rd, Nanchang, Jiangxi, 330006, China.
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14
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Horvat L, Antica M, Matulić M. Effect of Notch and PARP Pathways' Inhibition in Leukemic Cells. Cells 2018; 7:cells7060058. [PMID: 29903986 PMCID: PMC6025460 DOI: 10.3390/cells7060058] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 06/11/2018] [Accepted: 06/12/2018] [Indexed: 12/13/2022] Open
Abstract
Differentiation of blood cells is one of the most complex processes in the body. It is regulated by the action of transcription factors in time and space which creates a specific signaling network. In the hematopoietic signaling system, Notch is one of the main regulators of lymphocyte development. The aim of this study was to get insight into the regulation of Notch signalization and the influence of poly(ADP-ribose)polymerase (PARP) activity on this process in three leukemia cell lines obtained from B and T cells. PARP1 is an enzyme involved in posttranslational protein modification and chromatin structure changes. B and T leukemia cells were treated with Notch and PARP inhibitors, alone or in combination, for a prolonged period. The cells did not show cell proliferation arrest or apoptosis. Analysis of gene and protein expression set involved in Notch and PARP pathways revealed increase in JAGGED1 expression after PARP1 inhibition in B cell lines and changes in Ikaros family members in both B and T cell lines after γ-secretase inhibition. These data indicate that Notch and PARP inhibition, although not inducing differentiation in leukemia cells, induce changes in signaling circuits and chromatin modelling factors.
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Affiliation(s)
- Luka Horvat
- Department of Molecular Biology, Faculty of Science, University of Zagreb, Horvatovac 102A, 10000 Zagreb, Croatia.
| | - Mariastefania Antica
- Division of Molecular Biology, Rudjer Boskovic Institute, Bijenicka 54, 10000 Zagreb, Croatia.
| | - Maja Matulić
- Department of Molecular Biology, Faculty of Science, University of Zagreb, Horvatovac 102A, 10000 Zagreb, Croatia.
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15
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Animal models of T-cell acute lymphoblastic leukemia: mimicking the human disease. JOURNAL OF BIO-X RESEARCH 2018. [DOI: 10.1097/jbr.0000000000000001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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16
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Heizmann B, Kastner P, Chan S. The Ikaros family in lymphocyte development. Curr Opin Immunol 2018; 51:14-23. [DOI: 10.1016/j.coi.2017.11.005] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2017] [Revised: 11/21/2017] [Accepted: 11/30/2017] [Indexed: 10/18/2022]
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17
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Bellavia D, Checquolo S, Palermo R, Screpanti I. The Notch3 Receptor and Its Intracellular Signaling-Dependent Oncogenic Mechanisms. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2018; 1066:205-222. [PMID: 30030828 DOI: 10.1007/978-3-319-89512-3_10] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
During evolution, gene duplication of the Notch receptor suggests a progressive functional diversification. The Notch3 receptor displays a number of structural differences with respect to Notch1 and Notch2, most of which have been reported in the transmembrane and in the intracellular regions, mainly localized in the negative regulatory region (NRR) and trans-activation domain (TAD). Targeted deletion of Notch3 does not result in embryonic lethality, which is in line with its highly restricted tissue expression pattern. Importantly, deregulated Notch3 expression and/or activation, often results in disrupted cell differentiation and/or pathological development, most notably in oncogenesis in different cell contexts. Mechanistically this is due to Notch3-related genetic alterations or epigenetic or posttranslational control mechanisms. In this chapter we discuss the possible relationships between the structural differences and the pathological role of Notch3 in the control of mouse and human cancers. In future, targeting the unique features of Notch3-oncogenic mechanisms could be exploited to develop anticancer therapeutics.
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Affiliation(s)
- Diana Bellavia
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Saula Checquolo
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Rome, Italy
| | - Rocco Palermo
- Center for Life Nano Science@Sapienza, Istituto Italiano di Tecnologia, Rome, Italy
| | - Isabella Screpanti
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy.
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18
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Robles-Valero J, Lorenzo-Martín LF, Menacho-Márquez M, Fernández-Pisonero I, Abad A, Camós M, Toribio ML, Espinosa L, Bigas A, Bustelo XR. A Paradoxical Tumor-Suppressor Role for the Rac1 Exchange Factor Vav1 in T Cell Acute Lymphoblastic Leukemia. Cancer Cell 2017; 32:608-623.e9. [PMID: 29136506 PMCID: PMC5691892 DOI: 10.1016/j.ccell.2017.10.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 07/31/2017] [Accepted: 10/04/2017] [Indexed: 12/20/2022]
Abstract
Rho guanine exchange factors (GEFs), the enzymes that stimulate Rho GTPases, are deemed as potential therapeutic targets owing to their protumorigenic functions. However, the understanding of the spectrum of their pathobiological roles in tumors is still very limited. We report here that the GEF Vav1 unexpectedly possesses tumor-suppressor functions in immature T cells. This function entails the noncatalytic nucleation of complexes between the ubiquitin ligase Cbl-b and the intracellular domain of Notch1 (ICN1) that favors ICN1 ubiquitinylation and degradation. Ablation of Vav1 promotes ICN1 signaling and the development of T cell acute lymphoblastic leukemia (T-ALL). The downregulation of Vav1 is essential for the pathogenesis of human T-ALL of the TLX+ clinical subtype, further underscoring the suppressor role of this pathway.
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Affiliation(s)
- Javier Robles-Valero
- Centro de Investigación del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), CSIC - University of Salamanca, 37007 Salamanca, Spain
| | - L Francisco Lorenzo-Martín
- Centro de Investigación del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), CSIC - University of Salamanca, 37007 Salamanca, Spain
| | - Mauricio Menacho-Márquez
- Centro de Investigación del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), CSIC - University of Salamanca, 37007 Salamanca, Spain
| | - Isabel Fernández-Pisonero
- Centro de Investigación del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain
| | - Antonio Abad
- Centro de Investigación del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), CSIC - University of Salamanca, 37007 Salamanca, Spain
| | - Mireia Camós
- Hospital Sant Joan de Déu, 08950 Esplugues de Llobregat, Spain
| | - María L Toribio
- Centro de Biología Molecular Severo Ochoa, CSIC - Madrid Autonomous University, 28049 Madrid, Spain
| | - Lluis Espinosa
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), CSIC - University of Salamanca, 37007 Salamanca, Spain; Institut Hospital del Mar d'Investigacions Mèdiques, 08003 Barcelona, Spain
| | - Anna Bigas
- Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), CSIC - University of Salamanca, 37007 Salamanca, Spain; Institut Hospital del Mar d'Investigacions Mèdiques, 08003 Barcelona, Spain
| | - Xosé R Bustelo
- Centro de Investigación del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Instituto de Biología Molecular y Celular del Cáncer, CSIC - University of Salamanca, 37007 Salamanca, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), CSIC - University of Salamanca, 37007 Salamanca, Spain.
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19
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High selective pressure for Notch1 mutations that induce Myc in T-cell acute lymphoblastic leukemia. Blood 2016; 128:2229-2240. [PMID: 27670423 DOI: 10.1182/blood-2016-01-692855] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2016] [Accepted: 09/08/2016] [Indexed: 12/20/2022] Open
Abstract
Activating NOTCH1 mutations are frequent in human T-cell acute lymphoblastic leukemia (T-ALL) and Notch inhibitors (γ-secretase inhibitors [GSIs]) have produced responses in patients with relapsed, refractory disease. However, sustained responses, although reported, are uncommon, suggesting that other pathways can substitute for Notch in T-ALL. To address this possibility, we first generated KrasG12D transgenic mice with T-cell-specific expression of the pan-Notch inhibitor, dominant-negative Mastermind (DNMAML). These mice developed leukemia, but instead of accessing alternative oncogenic pathways, the tumor cells acquired Notch1 mutations and subsequently deleted DNMAML, reinforcing the notion that activated Notch1 is particularly transforming within the context of T-cell progenitors. We next took a candidate approach to identify oncogenic pathways downstream of Notch, focusing on Myc and Akt, which are Notch targets in T-cell progenitors. KrasG12D mice transduced with Myc developed T-ALLs that were GSI-insensitive and lacked Notch1 mutations. In contrast, KrasG12D mice transduced with myristoylated AKT developed GSI-sensitive T-ALLs that acquired Notch1 mutations. Thus, Myc can substitute for Notch1 in leukemogenesis, whereas Akt cannot. These findings in primary tumors extend recent work using human T-ALL cell lines and xenografts and suggest that the Notch/Myc signaling axis is of predominant importance in understanding both the selective pressure for Notch mutations in T-ALL and response and resistance of T-ALL to Notch pathway inhibitors.
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20
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Carofino BL, Ayanga B, Tracey LJ, Brooke-Bisschop T, Justice MJ. PRDM14 promotes RAG-dependent Notch1 driver mutations in mouse T-ALL. Biol Open 2016; 5:645-53. [PMID: 27106930 PMCID: PMC4874358 DOI: 10.1242/bio.017699] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
PRDM14 is an epigenetic regulator known for maintaining embryonic stem cell identity and resetting potency in primordial germ cells. However, hematopoietic expression of Prdm14 at supraphysiological levels results in fully penetrant and rapid-onset T-cell acute lymphoblastic leukemia (T-ALL) in the mouse. Here, we show that PRDM14-induced T-ALLs are driven by NOTCH1, a frequently mutated driver of human T-ALL. Notch1 is activated in this murine model via RAG-dependent promoter deletions and subsequent production of truncated, ligand-independent protein from downstream regions of the Notch1 locus. These T-ALLs also have focal changes in H3K4me3 deposition at the Notch1 locus and global increases in both H3K4me1 and H3K4me3. Using a PRDM14-FLAG mouse model, we show that PRDM14 binds within an intron of Notch1 prior to leukemia development. Our data support the idea that PRDM14 binding promotes a chromatin state that allows access of the RAG recombinase complex to cryptic RAG signal sequences embedded at the Notch1 locus. Indeed, breeding into a RAG recombination-deficient background abrogates T-ALL development and prevents Notch1 deletions, while allowing for transient hematopoietic stem cell (HSC)-like pre-leukemia cell expansion. Together, our data suggest that PRDM14 expands a progenitor cell population while promoting a permissive epigenetic state for the creation of driver mutations (here, in Notch1), enabling cancer development through the misappropriation of endogenous cellular DNA recombination machinery. Summary: PRDM14 promotes an epigenetic state that facilitates RAG-dependent Notch1 driver mutations, coupling progenitor cell expansion with genomic instability to produce T-ALL with shorter latency than other NOTCH1-driven mouse models.
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Affiliation(s)
- Brandi L Carofino
- Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, 77030 USA Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030 USA
| | - Bernard Ayanga
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030 USA
| | - Lauren J Tracey
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5S 1A8 Canada Genetics and Genome Biology, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, M5G 0A4 Canada
| | - Travis Brooke-Bisschop
- Genetics and Genome Biology, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, M5G 0A4 Canada
| | - Monica J Justice
- Interdepartmental Program in Translational Biology and Molecular Medicine, Baylor College of Medicine, Houston, TX, 77030 USA Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX, 77030 USA Department of Molecular Genetics, University of Toronto, Toronto, Ontario, M5S 1A8 Canada Genetics and Genome Biology, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, Ontario, M5G 0A4 Canada
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21
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Abstract
Recent investigations have provided an increasingly complete picture of the genetic landscape of chronic lymphocytic leukaemia (CLL). These analyses revealed that the CLL genome displays a high degree of heterogeneity between patients and within the same patient. In addition, they highlighted molecular mechanisms and functionally relevant biological programmes that may be important for the pathogenesis and therapeutic targeting of this disease. This Review focuses on recent insights into the understanding of CLL biology, with emphasis on the role of genetic lesions in the initiation and clinical progression of CLL. We also consider the translation of these findings into the development of risk-adapted and targeted therapeutic approaches.
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Affiliation(s)
- Giulia Fabbri
- Institute for Cancer Genetics, Columbia University, New York, New York 10032, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York 10032, USA
| | - Riccardo Dalla-Favera
- Institute for Cancer Genetics, Columbia University, New York, New York 10032, USA
- Herbert Irving Comprehensive Cancer Center, Columbia University, New York, New York 10032, USA
- Department of Pathology and Cell Biology and New York, New York 10032, USA
- Departments of Genetics and Development and Microbiology and Immunology, Columbia University, New York, New York 10032, USA
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22
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Mijušković M, Chou YF, Gigi V, Lindsay CR, Shestova O, Lewis SM, Roth DB. Off-Target V(D)J Recombination Drives Lymphomagenesis and Is Escalated by Loss of the Rag2 C Terminus. Cell Rep 2015; 12:1842-52. [PMID: 26365182 DOI: 10.1016/j.celrep.2015.08.034] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 07/07/2015] [Accepted: 08/08/2015] [Indexed: 11/29/2022] Open
Abstract
Genome-wide analysis of thymic lymphomas from Tp53(-/-) mice with wild-type or C-terminally truncated Rag2 revealed numerous off-target, RAG-mediated DNA rearrangements. A significantly higher fraction of these errors mutated known and suspected oncogenes/tumor suppressor genes than did sporadic rearrangements (p < 0.0001). This tractable mouse model recapitulates recent findings in human pre-B ALL and allows comparison of wild-type and mutant RAG2. Recurrent, RAG-mediated deletions affected Notch1, Pten, Ikzf1, Jak1, Phlda1, Trat1, and Agpat9. Rag2 truncation substantially increased the frequency of off-target V(D)J recombination. The data suggest that interactions between Rag2 and a specific chromatin modification, H3K4me3, support V(D)J recombination fidelity. Oncogenic effects of off-target rearrangements created by this highly regulated recombinase may need to be considered in design of site-specific nucleases engineered for genome modification.
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Affiliation(s)
- Martina Mijušković
- Department of Pathology and Laboratory Medicine, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Department of Genetics and Epidemiology, The Institute of Cancer Research, 15 Cotswold Road, Sutton, Surrey SM2 5NG, UK
| | - Yi-Fan Chou
- Department of Pathology and Laboratory Medicine, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Vered Gigi
- Department of Pathology and Laboratory Medicine, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; The Boston Consulting Group, 1735 Market Street, Philadelphia, PA 19103, USA
| | - Cory R Lindsay
- Department of Pathology and Laboratory Medicine, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Cardeza Foundation for Hematological Research, Thomas Jefferson University, 394 Jefferson Alumni Hall, 1020 Locust Street, Philadelphia, PA 19104, USA
| | - Olga Shestova
- Department of Pathology and Laboratory Medicine, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Translational Research Program, Abramson Family Research Cancer Institute, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Susanna M Lewis
- Department of Pathology and Laboratory Medicine, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
| | - David B Roth
- Department of Pathology and Laboratory Medicine, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA; Abramson Family Cancer Research Institute, Raymond and Ruth Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA.
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23
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Abstract
The modular, noncontiguous architecture of the antigen receptor genes necessitates their assembly through V(D)J recombination. This program of DNA breakage and rejoining occurs during early lymphocyte development, and depends on the RAG1 and RAG2 proteins, whose collaborative endonuclease activity targets specific DNA motifs enriched in the antigen receptor loci. This essential gene shuffling reaction requires lymphocytes to traverse several developmental stages wherein DNA breakage is tolerated, while minimizing the expense to overall genome integrity. Thus, RAG activity is subject to stringent temporal and spatial regulation. The RAG proteins themselves also contribute autoregulatory properties that coordinate their DNA cleavage activity with target chromatin structure, cell cycle status, and DNA repair pathways. Even so, lapses in regulatory restriction of RAG activity are apparent in the aberrant V(D)J recombination events that underlie many lymphomas. In this review, we discuss the current understanding of the RAG endonuclease, its widespread binding in the lymphocyte genome, its noncleavage activities that restrain its enzymatic potential, and the growing evidence of its evolution from an ancient transposase.
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24
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Blyth BJ, Kakinuma S, Sunaoshi M, Amasaki Y, Hirano-Sakairi S, Ogawa K, Shirakami A, Shang Y, Tsuruoka C, Nishimura M, Shimada Y. Genetic Analysis of T Cell Lymphomas in Carbon Ion-Irradiated Mice Reveals Frequent Interstitial Chromosome Deletions: Implications for Second Cancer Induction in Normal Tissues during Carbon Ion Radiotherapy. PLoS One 2015; 10:e0130666. [PMID: 26125582 PMCID: PMC4488329 DOI: 10.1371/journal.pone.0130666] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 05/25/2015] [Indexed: 02/07/2023] Open
Abstract
Monitoring mice exposed to carbon ion radiotherapy provides an indirect method to evaluate the potential for second cancer induction in normal tissues outside the radiotherapy target volume, since such estimates are not yet possible from historical patient data. Here, male and female B6C3F1 mice were given single or fractionated whole-body exposure(s) to a monoenergetic carbon ion radiotherapy beam at the Heavy Ion Medical Accelerator in Chiba, Japan, matching the radiation quality delivered to the normal tissue ahead of the tumour volume (average linear energy transfer = 13 keV.μm-1) during patient radiotherapy protocols. The mice were monitored for the remainder of their lifespan, and a large number of T cell lymphomas that arose in these mice were analysed alongside those arising following an equivalent dose of 137Cs gamma ray-irradiation. Using genome-wide DNA copy number analysis to identify genomic loci involved in radiation-induced lymphomagenesis and subsequent detailed analysis of Notch1, Ikzf1, Pten, Trp53 and Bcl11b genes, we compared the genetic profile of the carbon ion- and gamma ray-induced tumours. The canonical set of genes previously associated with radiation-induced T cell lymphoma was identified in both radiation groups. While the pattern of disruption of the various pathways was somewhat different between the radiation types, most notably Pten mutation frequency and loss of heterozygosity flanking Bcl11b, the most striking finding was the observation of large interstitial deletions at various sites across the genome in carbon ion-induced tumours, which were only seen infrequently in the gamma ray-induced tumours analysed. If such large interstitial chromosomal deletions are a characteristic lesion of carbon ion irradiation, even when using the low linear energy transfer radiation to which normal tissues are exposed in radiotherapy patients, understanding the dose-response and tissue specificity of such DNA damage could prove key to assessing second cancer risk in carbon ion radiotherapy patients.
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Affiliation(s)
- Benjamin J. Blyth
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Shizuko Kakinuma
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Masaaki Sunaoshi
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Yoshiko Amasaki
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Shinobu Hirano-Sakairi
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Kanae Ogawa
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Ayana Shirakami
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Yi Shang
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Chizuru Tsuruoka
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Mayumi Nishimura
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
| | - Yoshiya Shimada
- Radiobiology for Children’s Health Program, Research Center for Radiation Protection, National Institute of Radiological Sciences, Chiba, Japan
- * E-mail:
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Bottardi S, Mavoungou L, Milot E. IKAROS: a multifunctional regulator of the polymerase II transcription cycle. Trends Genet 2015; 31:500-8. [PMID: 26049627 DOI: 10.1016/j.tig.2015.05.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2015] [Revised: 05/06/2015] [Accepted: 05/07/2015] [Indexed: 11/16/2022]
Abstract
Transcription factors are important determinants of lineage specification during hematopoiesis. They favor recruitment of cofactors involved in epigenetic regulation, thereby defining patterns of gene expression in a development- and lineage-specific manner. Additionally, transcription factors can facilitate transcription preinitiation complex (PIC) formation and assembly on chromatin. Interestingly, a few lineage-specific transcription factors, including IKAROS, also regulate transcription elongation. IKAROS is a tumor suppressor frequently inactivated in leukemia and associated with a poor prognosis. It forms a complex with the nucleosome remodeling and deacetylase (NuRD) complex and the positive transcription elongation factor b (P-TEFb), which is required for productive transcription elongation. It has also been reported that IKAROS interacts with factors involved in transcription termination. Here we review these and other recent findings that establish IKAROS as the first transcription factor found to act as a multifunctional regulator of the transcription cycle in hematopoietic cells.
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Affiliation(s)
- Stefania Bottardi
- Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Montreal, QC H1T 3W5, Canada; Department of Medicine, University of Montreal, 5415 boulevard l'Assomption, Montreal, QC H1T 2M4, Canada
| | - Lionel Mavoungou
- Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Montreal, QC H1T 3W5, Canada; Department of Medicine, University of Montreal, 5415 boulevard l'Assomption, Montreal, QC H1T 2M4, Canada
| | - Eric Milot
- Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Montreal, QC H1T 3W5, Canada; Department of Medicine, University of Montreal, 5415 boulevard l'Assomption, Montreal, QC H1T 2M4, Canada.
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26
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Witkowski MT, Cimmino L, Hu Y, Trimarchi T, Tagoh H, McKenzie MD, Best SA, Tuohey L, Willson TA, Nutt SL, Busslinger M, Aifantis I, Smyth GK, Dickins RA. Activated Notch counteracts Ikaros tumor suppression in mouse and human T-cell acute lymphoblastic leukemia. Leukemia 2015; 29:1301-11. [PMID: 25655195 PMCID: PMC4845663 DOI: 10.1038/leu.2015.27] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 01/28/2015] [Accepted: 01/30/2015] [Indexed: 12/13/2022]
Abstract
Activating NOTCH1 mutations occur in ~60% of human T-cell acute lymphoblastic leukemias (T-ALLs), and mutations disrupting the transcription factor IKZF1 (IKAROS) occur in ~5% of cases. To investigate the regulatory interplay between these driver genes, we have used a novel transgenic RNA interference mouse model to produce primary T-ALLs driven by reversible Ikaros knockdown. Restoring endogenous Ikaros expression in established T-ALL in vivo acutely represses Notch1 and its oncogenic target genes including Myc, and in multiple primary leukemias causes disease regression. In contrast, leukemias expressing high levels of endogenous or engineered forms of activated intracellular Notch1 (ICN1) resembling those found in human T-ALL rapidly relapse following Ikaros restoration, indicating that ICN1 functionally antagonizes Ikaros in established disease. Furthermore, we find that IKAROS mRNA expression is significantly reduced in a cohort of primary human T-ALL patient samples with activating NOTCH1/FBXW7 mutations, but is upregulated upon acute inhibition of aberrant NOTCH signaling across a panel of human T-ALL cell lines. These results demonstrate for the first time that aberrant NOTCH activity compromises IKAROS function in mouse and human T-ALL, and provide a potential explanation for the relative infrequency of IKAROS gene mutations in human T-ALL.
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Affiliation(s)
- MT Witkowski
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - L Cimmino
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
- Department of Pathology, NYU School of Medicine, New York, NY, USA
| | - Y Hu
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - T Trimarchi
- Department of Pathology, NYU School of Medicine, New York, NY, USA
| | - H Tagoh
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - MD McKenzie
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - SA Best
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - L Tuohey
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - TA Willson
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - SL Nutt
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
- Molecular Immunology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
| | - M Busslinger
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna, Austria
| | - I Aifantis
- Department of Pathology, NYU School of Medicine, New York, NY, USA
| | - GK Smyth
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Mathematics and Statistics, University of Melbourne, Parkville, VIC, Australia
| | - RA Dickins
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, VIC, Australia
- Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
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27
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Lubeck BA, Lapinski PE, Oliver JA, Ksionda O, Parada LF, Zhu Y, Maillard I, Chiang M, Roose J, King PD. Cutting Edge: Codeletion of the Ras GTPase-Activating Proteins (RasGAPs) Neurofibromin 1 and p120 RasGAP in T Cells Results in the Development of T Cell Acute Lymphoblastic Leukemia. THE JOURNAL OF IMMUNOLOGY 2015; 195:31-5. [PMID: 26002977 DOI: 10.4049/jimmunol.1402639] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 04/28/2015] [Indexed: 12/11/2022]
Abstract
Ras GTPase-activating proteins (RasGAPs) inhibit signal transduction initiated through the Ras small GTP-binding protein. However, which members of the RasGAP family act as negative regulators of T cell responses is not completely understood. In this study, we investigated potential roles for the RasGAPs RASA1 and neurofibromin 1 (NF1) in T cells through the generation and analysis of T cell-specific RASA1 and NF1 double-deficient mice. In contrast to mice lacking either RasGAP alone in T cells, double-deficient mice developed T cell acute lymphoblastic leukemia/lymphoma, which originated at an early point in T cell development and was dependent on activating mutations in the Notch1 gene. These findings highlight RASA1 and NF1 as cotumor suppressors in the T cell lineage.
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Affiliation(s)
- Beth A Lubeck
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Philip E Lapinski
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Jennifer A Oliver
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Olga Ksionda
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143
| | - Luis F Parada
- Department of Developmental Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390
| | - Yuan Zhu
- Division of Molecular Medicine and Genetics, University of Michigan Medical School, Ann Arbor, MI 48109; and
| | - Ivan Maillard
- Division of Hematology and Oncology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Mark Chiang
- Division of Hematology and Oncology, Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, MI 48109
| | - Jeroen Roose
- Department of Anatomy, University of California, San Francisco, San Francisco, CA 94143
| | - Philip D King
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI 48109;
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28
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Wang H, Zang C, Liu XS, Aster JC. The role of Notch receptors in transcriptional regulation. J Cell Physiol 2015; 230:982-8. [PMID: 25418913 DOI: 10.1002/jcp.24872] [Citation(s) in RCA: 88] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Accepted: 11/19/2014] [Indexed: 12/22/2022]
Abstract
Notch signaling has pleiotropic context-specific functions that have essential roles in many processes, including embryonic development and maintenance and homeostasis of adult tissues. Aberrant Notch signaling (both hyper- and hypoactive) is implicated in a number of human developmental disorders and many cancers. Notch receptor signaling is mediated by tightly regulated proteolytic cleavages that lead to the assembly of a nuclear Notch transcription complex, which drives the expression of downstream target genes and thereby executes Notch's functions. Thus, understanding regulation of gene expression by Notch is central to deciphering how Notch carries out its many activities. Here, we summarize the recent findings pertaining to the complex interplay between the Notch transcriptional complex and interacting factors involved in transcriptional regulation, including co-activators, cooperating transcription factors, and chromatin regulators, and discuss emerging data pertaining to the role of Notch-regulated noncoding RNAs in transcription.
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Affiliation(s)
- Hongfang Wang
- Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
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29
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Hua C, Guo H, Bu J, Zhou M, Cheng H, He F, Wang J, Wang X, Zhang Y, Wang Q, Zhou J, Cheng T, Xu M, Yuan W. Rictor/mammalian target of rapamycin 2 regulates the development of Notch1 induced murine T-cell acute lymphoblastic leukemia via forkhead box O3. Exp Hematol 2014; 42:1031-40.e1-4. [PMID: 25201756 DOI: 10.1016/j.exphem.2014.08.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 08/29/2014] [Accepted: 08/31/2014] [Indexed: 11/17/2022]
Abstract
Mammalian target of rapamycin (mTOR) is composed of two distinct biochemical complexes, mTORC1 and mTORC2. In response to nutrients and growth factors, mTORC1 is known to control cellular growth by regulating the translational regulators S6 kinase 1 and 4E binding protein 1, whereas mTORC2 mediates cell proliferation and survival by activating Akt through phosphorylation at Ser473. Studies have shown that the deregulation of mTORC2 leads to the development of myeloproliferative disorder and leukemia in the phosphatase and tensin homolog deleted on chromosome ten (PTEN)-deleted mouse model. However, the mechanism by which mTORC2 specifically affects leukemogenesis is still not fully understood. Here, we investigated the role of mTORC2 in NOTCH1-driven T-cell acute lymphoblastic leukemia (T-ALL) in a Rictor-deficient mouse model. We found that, by deleting Rictor, an essential component of mTORC2, leukemia progression was significantly suppressed by arresting a greater proportion of Rictor(△/△) leukemic cells at the G0 phase of the cell cycle. Furthermore, the absence of Rictor led to the overexpression of chemotaxis-related genes, such as CCR2, CCR4 and CXCR4, which contributed to the homing and migration of Rictor-deficient T-ALL cells to the spleen but not the bone marrow. In addition, we demonstrated that inactivation of mTORC2 caused the overexpression of forkhead box O3 and its downstream effectors and eased the progression of leukemia in T-ALL mice. Our study thus indicates that forkhead box O3 could be a potential drug target for the treatment of T-ALL leukemia.
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Affiliation(s)
- Chunlan Hua
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Huidong Guo
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Jiachen Bu
- Laboratory of Genome Variations and Precision Bio-Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Mi Zhou
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Hui Cheng
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Fuhong He
- Laboratory of Genome Variations and Precision Bio-Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Jinhong Wang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Xiaomin Wang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Yinchi Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Qianfei Wang
- Laboratory of Genome Variations and Precision Bio-Medicine, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing, China
| | - Jianfeng Zhou
- Cancer Biology Research Center, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Tao Cheng
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Mingjiang Xu
- Herman B Wells Center for Pediatric Research, Indiana University School of Medicine, Indianapolis, IN, USA
| | - Weiping Yuan
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Center for Stem Cell Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China.
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30
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Yoshida T, Georgopoulos K. Ikaros fingers on lymphocyte differentiation. Int J Hematol 2014; 100:220-9. [PMID: 25085254 DOI: 10.1007/s12185-014-1644-5] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2014] [Revised: 07/15/2014] [Accepted: 07/15/2014] [Indexed: 11/29/2022]
Abstract
The Ikaros family of DNA-binding proteins are critical regulators of lymphocyte differentiation. In multipotent, hematopoietic progenitors, Ikaros supports transcriptional priming of genes promoting lymphocyte differentiation. Ikaros targets the Nucleosome Remodeling Deacetylase (NuRD) complex to lymphoid lineage genes, thereby increasing chromatin accessibility and transcriptional priming. After lymphoid lineage specification, Ikaros expression is raised to levels characteristic of intermediate B cell and T cell precursors, which is necessary to support maturation and prevent leukemogenesis. Loss of Ikaros in T cell precursors allows the NuRD complex to repress lymphocyte genes and extends its targeting to genes that support growth and proliferation, causing their activation and triggering a cascade of events that leads to leukemogenesis. Loss of Ikaros in B cell precursors blocks differentiation and perpetuates stromal adhesion by enhancing integrin signaling. The combination of integrin and cytokine signaling in Ikaros-deficient pre-B cells promotes their survival and self-renewal. The stages of lymphocyte differentiation that are highly dependent on Ikaros are underscored by changes in Ikaros transcription, supported by a complex network of stage-specific regulatory networks that converge upon the Ikzf1 locus. It is increasingly apparent that understanding the regulatory networks that operate upstream and downstream of Ikaros is critical not only for our understanding of normal lymphopoiesis, but also in placing the right finger on the mechanisms that support hematopoietic malignancies in mouse and human.
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Affiliation(s)
- Toshimi Yoshida
- Cutaneous Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Bldg.149-3, 13th st, Charlestown, MA, 02129, USA,
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31
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Tanaka M, Yamazaki Y, Kanno Y, Igarashi K, Aisaki KI, Kanno J, Nakamura T. Ewing's sarcoma precursors are highly enriched in embryonic osteochondrogenic progenitors. J Clin Invest 2014; 124:3061-74. [PMID: 24911143 DOI: 10.1172/jci72399] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 04/10/2014] [Indexed: 12/18/2022] Open
Abstract
Ewing's sarcoma is a highly malignant bone tumor found in children and adolescents, and the origin of this malignancy is not well understood. Here, we introduced a Ewing's sarcoma-associated genetic fusion of the genes encoding the RNA-binding protein EWS and the transcription factor ETS (EWS-ETS) into a fraction of cells enriched for osteochondrogenic progenitors derived from the embryonic superficial zone (eSZ) of long bones collected from late gestational murine embryos. EWS-ETS fusions efficiently induced Ewing's sarcoma-like small round cell sarcoma formation by these cells. Analysis of the eSZ revealed a fraction of a precursor cells that express growth/differentiation factor 5 (Gdf5), the transcription factor Erg, and parathyroid hormone-like hormone (Pthlh), and selection of the Pthlh-positive fraction alone further enhanced EWS-ETS-dependent tumor induction. Genes downstream of the EWS-ETS fusion protein were quite transcriptionally active in eSZ cells, especially in regions in which the chromatin structure of the ETS-responsive locus was open. Inhibition of β-catenin, poly (ADP-ribose) polymerase 1 (PARP1), or enhancer of zeste homolog 2 (EZH2) suppressed cell growth in a murine model of Ewing's sarcoma, suggesting the utility of the current system as a preclinical model. These results indicate that eSZ cells are highly enriched in precursors to Ewing's sarcoma and provide clues to the histogenesis of Ewing's sarcoma in bone.
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32
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Tiemessen MM, Staal FJT. Wnt signaling in leukemias and myeloma: T-cell factors are in control. Future Oncol 2014; 9:1757-72. [PMID: 24156335 DOI: 10.2217/fon.13.122] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Aberrant activation of the Wnt pathway has been implicated in the pathogenesis of many malignancies, especially solid tumors. During the past decade it also became clear that in hematological malignancies abnormal regulation of the Wnt pathway can either be causative or enhance disease progression, which will be discussed in detail in this review.
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Affiliation(s)
- Machteld M Tiemessen
- Department of Immunohematology & Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
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33
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Geimer Le Lay AS, Oravecz A, Mastio J, Jung C, Marchal P, Ebel C, Dembélé D, Jost B, Le Gras S, Thibault C, Borggrefe T, Kastner P, Chan S. The tumor suppressor Ikaros shapes the repertoire of notch target genes in T cells. Sci Signal 2014; 7:ra28. [PMID: 24643801 DOI: 10.1126/scisignal.2004545] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The Notch signaling pathway is activated in many cell types, but its effects are cell type- and stage-specific. In the immune system, Notch activity is required for the differentiation of T cell progenitors, but it is reduced in more mature thymocytes, in which Notch is oncogenic. Studies based on single-gene models have suggested that the tumor suppressor protein Ikaros plays an important role in repressing the transcription of Notch target genes. We used genome-wide analyses, including chromatin immunoprecipitation sequencing, to identify genes controlled by Notch and Ikaros in gain- and loss-of-function experiments. We found that Ikaros bound to and directly repressed the expression of most genes that are activated by Notch. Specific deletion of Ikaros in thymocytes led to the persistent expression of Notch target genes that are essential for T cell maturation, as well as the rapid development of T cell leukemias in mice. Expression of Notch target genes that are normally silent in T cells, but are activated by Notch in other cell types, occurred in T cells of mice genetically deficient in Ikaros. We propose that Ikaros shapes the timing and repertoire of the Notch transcriptional response in T cells through widespread targeting of elements adjacent to Notch regulatory sequences. These results provide a molecular framework for understanding the regulation of tissue-specific and tumor-related Notch responses.
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Affiliation(s)
- Anne-Solen Geimer Le Lay
- 1Institut de Génétique et de Biologie Moléculaire et Cellulaire (IGBMC), INSERM U964, CNRS UMR 7104, Université de Strasbourg, 67404 Illkirch, France
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Illegitimate V(D)J recombination-mediated deletions in Notch1 and Bcl11b are not sufficient for extensive clonal expansion and show minimal age or sex bias in frequency or junctional processing. Mutat Res 2014; 761:34-48. [PMID: 24530429 DOI: 10.1016/j.mrfmmm.2014.01.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2013] [Revised: 12/23/2013] [Accepted: 01/28/2014] [Indexed: 01/22/2023]
Abstract
Illegitimate V(D)J recombination at oncogenes and tumor suppressor genes is implicated in formation of several T cell malignancies. Notch1 and Bcl11b, genes involved in developing T cell specification, selection, proliferation, and survival, were previously shown to contain hotspots for deletional illegitimate V(D)J recombination associated with radiation-induced thymic lymphoma. Interestingly, these deletions were also observed in wild-type animals. In this study, we conducted frequency, clonality, and junctional processing analyses of Notch1 and Bcl11b deletions during mouse development and compared results to published analyses of authentic V(D)J rearrangements at the T cell receptor beta (TCRβ) locus and illegitimate V(D)J deletions observed at the human, nonimmune HPRT1 locus not involved in T cell malignancies. We detect deletions in Notch1 and Bcl11b in thymic and splenic T cell populations, consistent with cells bearing deletions in the circulating lymphocyte pool. Deletions in thymus can occur in utero, increase in frequency between fetal and postnatal stages, are detected at all ages examined between fetal and 7 months, exhibit only limited clonality (contrasting with previous results in radiation-sensitive mouse strains), and consistent with previous reports are more frequent in Bcl11b, partially explained by relatively high Recombination Signal Information Content (RIC) scores. Deletion junctions in Bcl11b exhibit greater germline nucleotide loss, while in Notch1 palindromic (P) nucleotides are more abundant, although average P nucleotide length is similar for both genes and consistent with results at the TCRβ locus. Non-templated (N) nucleotide insertions appear to increase between fetal and postnatal stages for Notch1, consistent with normal terminal deoxynucleotidyl transferase (TdT) activity; however, neonatal Bcl11b junctions contain elevated levels of N insertions. Finally, contrasting with results at the HPRT1 locus, we find no obvious age or gender bias in junctional processing, and inverted repeats at recessed coding ends (Pr nucleotides) correspond mostly to single-base additions consistent with normal TdT activity.
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35
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Palau N, Julià A, Ferrándiz C, Puig L, Fonseca E, Fernández E, López-Lasanta M, Tortosa R, Marsal S. Genome-wide transcriptional analysis of T cell activation reveals differential gene expression associated with psoriasis. BMC Genomics 2013; 14:825. [PMID: 24267790 PMCID: PMC4046651 DOI: 10.1186/1471-2164-14-825] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Accepted: 11/19/2013] [Indexed: 12/28/2022] Open
Abstract
BACKGROUND Psoriasis is a chronic autoimmune disease in which T cells have a predominant role in initiating and perpetuating the chronic inflammation in skin. However, the mechanisms that regulate T cell activation in psoriasis are still incompletely understood. The objective of the present study was to characterize the main genetic pathways associated with T cell activation in psoriasis. RESULTS Gene expression profiles from in vitro activated T cells were obtained from 17 psoriasis patients and 7 healthy controls using Illumina HT-12 v4 microarrays. From a total of 47,321 analyzed transcripts, 42 genes were found to be differentially expressed between psoriasis and controls (FDR p-value < 0.1, absolute fold-change > 1.2). Using an independent cohort of 8 patients and 8 healthy controls we validated the overexpression of SPATS2L (p-value =0.0009) and KLF6 (p-value =0.0012) genes in activated T cells from psoriasis patients. Using weighted correlation analysis we identified SPATS2L and KLF6 coexpression networks, which were also significantly associated with psoriasis (p-value < 0.05). Gene Ontology analysis allowed the identification of several biological processes associated with each coexpression network. Finally, using Gene Set Enrichment Analysis over the global T cell transcriptome we also found additional genetic pathways strongly associated with psoriasis (p-value < 0.0001). CONCLUSIONS This study has identified two new genes, SPATS2L and KLF6, strongly associated with T cell activation in psoriasis. Functional analyses of the gene expression profiles also revealed new biological processes and genetic pathways associated with psoriasis. The results of this study provide an important insight into the biology of this common chronic inflammatory disease.
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Affiliation(s)
- Nuria Palau
- Rheumatology Research Group, Vall d'Hebron Research Institute, Barcelona 08035, Spain.
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Zhang Y, Hua C, Cheng H, Wang W, Hao S, Xu J, Wang X, Gao Y, Zhu X, Cheng T, Yuan W. Distinct sensitivity of CD8+ CD4- and CD8+ CD4+ leukemic cell subpopulations to cyclophosphamide and rapamycin in Notch1-induced T-ALL mouse model. Leuk Res 2013; 37:1592-601. [PMID: 24090996 DOI: 10.1016/j.leukres.2013.09.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2013] [Revised: 07/01/2013] [Accepted: 09/09/2013] [Indexed: 01/13/2023]
Abstract
The Notch1 signaling pathway plays an essential role in cell growth and differentiation. Over-expression of the intracellular Notch1 domain (ICN1) in murine hematopoietic cells is able to induce robust T-cell acute lymphoblastic leukemia (T-ALL) in mice. Here we explored the drug sensitivity of T-ALL cells in two subpopulations of CD8(+)CD4(+) and CD8(+)CD4(-) cells in Notch1-induced T-ALL mice. We found that Notch1 induced T-ALL cells could be decreased by chemotherapeutic drug cyclophosphamide (CTX). CD8(+)CD4(-) T-ALL cells were more sensitive to CTX treatment than CD8(+)CD4(+) T-ALL cells. The percentage of apoptotic cells induced by CTX treatment was higher in CD8(+)CD4(-) T-ALL cells. T-ALL cells were also inhibited by inhibitor of mTORC1 rapamycin. CD8(+)CD4(+) T-ALL cells were more susceptible to rapamycin treatment than CD8(+)CD4(-) T-ALL cells. Rapamycin treatment selectively arrested more CD8(+)CD4(+) T-ALL cells at G0 phase of cell cycle. A combination of the two drugs significantly improved overall survival of T-ALL bearing mice when compared with CTX or rapamycin alone. These results indicated that CD8(+)CD4(+) and CD8(+)CD4(-) leukemia cell populations had distinct drug sensitivity.
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Affiliation(s)
- Yingchi Zhang
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China; Center for Stem Cell Medicine, Chinese Academy of Medical Sciences, Beijing 100730, China
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Abstract
Ikaros is a critical regulator of lymphocyte development and homeostasis; thus, understanding its transcriptional regulation is important from both developmental and clinical perspectives. Using a mouse transgenic reporter approach, we functionally characterized a network of highly conserved cis-acting elements at the Ikzf1 locus. We attribute B-cell and myeloid but not T-cell specificity to the main Ikzf1 promoter. Although this promoter was unable to counter local chromatin silencing effects, each of the 6 highly conserved Ikzf1 intronic enhancers alleviated silencing. Working together, the Ikzf1 enhancers provided locus control region activity, allowing reporter expression in a position and copy-independent manner. Only 1 of the Ikzf1 enhancers was responsible for the progressive upregulation of Ikaros expression from hematopoietic stem cells to lymphoid-primed multipotent progenitors to T-cell precursors, which are stages of differentiation dependent on Ikaros for normal outcome. Thus, Ikzf1 is regulated by both epigenetic and transcriptional factors that target its enhancers in both redundant and specific fashions to provide an expression profile supportive of normal lymphoid lineage progression and homeostasis. Mutations in the Ikzf1 regulatory elements and their interacting factors are likely to have adverse effects on lymphopoiesis and contribute to leukemogenesis.
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Smeets MFMA, Chan AC, Dagger S, Bradley CK, Wei A, Izon DJ. Fli-1 overexpression in hematopoietic progenitors deregulates T cell development and induces pre-T cell lymphoblastic leukaemia/lymphoma. PLoS One 2013; 8:e62346. [PMID: 23667468 PMCID: PMC3646842 DOI: 10.1371/journal.pone.0062346] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/20/2013] [Indexed: 12/28/2022] Open
Abstract
The Ets transcription factor Fli-1 is preferentially expressed in hematopoietic tissues and cells, including immature T cells, but the role of Fli-1 in T cell development has not been closely examined. To address this we retrovirally overexpressed Fli-1 in various in vitro and in vivo settings and analysed its effect on T cell development. We found that Fli-1 overexpression perturbed the DN to DP transition and inhibited CD4 development whilst enhancing CD8 development both in vitro and in vivo. Surprisingly, Fli-1 overexpression in vivo eventuated in development of pre-T cell lymphoblastic leukaemia/lymphoma (pre-T LBL). Known Fli-1 target genes such as the pro-survival Bcl-2 family members were not found to be upregulated. In contrast, we found increased NOTCH1 expression in all Fli-1 T cells and detected Notch1 mutations in all tumours. These data show a novel function for Fli-1 in T cell development and leukaemogenesis and provide a new mouse model of pre-T LBL to identify treatment options that target the Fli-1 and Notch1 signalling pathways.
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Affiliation(s)
- Monique F. M. A. Smeets
- Haematology and Leukaemia Unit, St. Vincent’s Institute, University of Melbourne, Fitzroy, Victoria, Australia
| | - Angela C. Chan
- Department of Microbiology and Immunology, University of Melbourne, Parkville, Victoria, Australia
| | - Samantha Dagger
- School of Pathology and Laboratory Medicine, University of Western Australia, Crawley, Western Australia, Australia
| | | | - Andrew Wei
- Department of Clinical Haematology, The Alfred Hospital and The Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria, Australia
| | - David J. Izon
- Haematology and Leukaemia Unit, St. Vincent’s Institute, University of Melbourne, Fitzroy, Victoria, Australia
- * E-mail:
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Vecchio L, Seke Etet PF, Kipanyula MJ, Krampera M, Nwabo Kamdje AH. Importance of epigenetic changes in cancer etiology, pathogenesis, clinical profiling, and treatment: what can be learned from hematologic malignancies? Biochim Biophys Acta Rev Cancer 2013; 1836:90-104. [PMID: 23603458 DOI: 10.1016/j.bbcan.2013.04.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 01/25/2013] [Accepted: 04/10/2013] [Indexed: 02/06/2023]
Abstract
Epigenetic alterations represent a key cancer hallmark, even in hematologic malignancies (HMs) or blood cancers, whose clinical features display a high inter-individual variability. Evidence accumulated in recent years indicates that inactivating DNA hypermethylation preferentially targets the subset of polycomb group (PcG) genes that are regulators of developmental processes. Conversely, activating DNA hypomethylation targets oncogenic signaling pathway genes, but outcomes of both events lead in the overexpression of oncogenic signaling pathways that contribute to the stem-like state of cancer cells. On the basis of recent evidence from population-based, clinical and experimental studies, we hypothesize that factors associated with risk for developing a HM, such as metabolic syndrome and chronic inflammation, trigger epigenetic mechanisms to increase the transcriptional expression of oncogenes and activate oncogenic signaling pathways. Among others, signaling pathways associated with such risk factors include pro-inflammatory nuclear factor κB (NF-κB), and mitogenic, growth, and survival Janus kinase (JAK) intracellular non-receptor tyrosine kinase-triggered pathways, which include signaling pathways such as transducer and activator of transcription (STAT), Ras GTPases/mitogen-activated protein kinases (MAPKs)/extracellular signal-related kinases (ERKs), phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR), and β-catenin pathways. Recent findings on epigenetic mechanisms at work in HMs and their importance in the etiology and pathogenesis of these diseases are herein summarized and discussed. Furthermore, the role of epigenetic processes in the determination of biological identity, the consequences for interindividual variability in disease clinical profile, and the potential of epigenetic drugs in HMs are also considered.
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Affiliation(s)
- Lorella Vecchio
- Laboratory of Cytometry, Institute of Molecular Genetics, CNR, University of Pavia, 27100 Pavia, Italy
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40
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Abstract
Ikaros is the founding member of a family of zinc finger transcription factors whose function during early hematopoietic development is required for differentiation into the three major hematopoietic lineages. Ikaros deletions have been described in human malignancies, particularly precursor B-cell leukemia. Deletions of this transcription factor appear to mediate leukemogenesis, although the exact mechanism is unclear. This article reviews the structure and function of Ikaros proteins in chromatin remodeling and gene expression as well as the current knowledge of Ikaros deletions in human malignancies. A new proteomic platform, mass cytometry, is introduced which allows measurements of greater than 30 parameters at the single-cell level and should thus provide a greater level of detail to unravel the mechanistic consequences of Ikaros dysfunction in leukemia.
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Ikaros inhibits megakaryopoiesis through functional interaction with GATA-1 and NOTCH signaling. Blood 2013; 121:2440-51. [PMID: 23335373 DOI: 10.1182/blood-2012-08-450627] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The transcription factor Ikaros regulates the development of hematopoietic cells. Ikaros-deficient animals fail to develop B cells and display a T-cell malignancy, which is correlated with altered Notch signaling. Recently, loss of Ikaros was associated with progression of myeloproliferative neoplasms to acute myeloid leukemia and increasing evidence shows that Ikaros is also critical for the regulation of myeloid development. Previous studies showed that Ikaros-deficient mice have increased megakaryopoiesis, but the molecular mechanism of this phenomenon remains unknown. Here, we show that Ikaros overexpression decreases NOTCH-induced megakaryocytic specification, and represses expression of several megakaryocytic genes including GATA-1 to block differentiation and terminal maturation. We also demonstrate that Ikaros expression is differentially regulated by GATA-2 and GATA-1 during megakaryocytic differentiation and reveal that the combined loss of Ikzf1 and Gata1 leads to synthetic lethality in vivo associated with prominent defects in erythroid cells and an expansion of megakaryocyte progenitors. Taken together, our observations demonstrate an important functional interplay between Ikaros, GATA factors, and the NOTCH signaling pathway in specification and homeostasis of the megakaryocyte lineage.
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Yamamoto K, Nakamachi Y, Yakushijin K, Miyata Y, Okamura A, Kawano S, Matsuoka H, Minami H. A novel TRB@/NOTCH1 fusion gene in T-cell lymphoblastic lymphoma with t(7;9)(q34;q34). Eur J Haematol 2012; 90:68-75. [PMID: 23033986 DOI: 10.1111/ejh.12019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/22/2012] [Indexed: 01/01/2023]
Abstract
BACKGROUND In T-cell acute lymphoblastic leukemia/lymphoma (T-ALL/LBL), activating mutations of NOTCH1 are observed in more than 50% of cases, whereas the t(7;9)(q34;q34) involving NOTCH1 at 9q34 and TRB@ at 7q34 is an extremely rare but recurrent translocation. PATIENT A 41-year-old male with a large mediastinal mass, pleural effusion, and lymphadenopathy was diagnosed as having T-LBL. Lymphoma cells were positive for CD4, CD8, CD2, CD3, CD5, CD7, CD10, and TdT. RESULTS G-banding and spectral karyotyping of pleural effusion cells showed 47,XY,dup(1)(q21q32),t(7;9)(q34;q34),+20. Genomic polymerase chain reaction (PCR) revealed that the 5' end of TRB@ J1-5 was connected with the middle of NOTCH1 exon 25 (434 bp downstream from its 5' end) in a 'head-to-head' configuration on the der(9)t(7;9), although nine extra bases were inserted between the two genes. Reverse transcription-PCR confirmed expression of the TRB@/NOTCH1 fusion transcripts. Similarly, the 5' end of J1-5 was fused to the shortened exon 25 with nine extra bases. The NOTCH1 breakpoint in exon 25 was very close to transcription start sites of deleted Notch1 in murine T-ALL. CONCLUSIONS The TRB@/NOTCH1 fusion gene with a NOTCH1 breakpoint in exon 25, which has not previously been detected in four other reported cases with t(7;9), could lead to aberrant expression of the truncated NOTCH1 by TRB@ enhancer elements. The resultant NOTCH1 receptor deleting most of the extracellular domain may be implicated in the pathogenesis of T-LBL by ligand-independent, constitutive activation of the NOTCH1 pathway, suggesting avenues for future therapy with γ-secretase inhibitors.
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Affiliation(s)
- Katsuya Yamamoto
- Division of Medical Oncology/Hematology, Department of Medicine, Kobe University Graduate School of Medicine, Kobe, Japan.
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Xi Y, Li YS, Tang HB. High mobility group A1 protein acts as a new target of Notch1 signaling and regulates cell proliferation in T leukemia cells. Mol Cell Biochem 2012; 374:173-80. [PMID: 23229232 DOI: 10.1007/s11010-012-1517-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Accepted: 11/07/2012] [Indexed: 11/30/2022]
Abstract
Active mutations of Notch1 play pivotal roles during leukemogenesis, but the downstream targets and molecular mechanisms of activated Notch1 signaling have not yet been fully clarified. In this study, we detected the overexpression of the high mobility group A1 (HMGA1) and activation of Notch1 signaling in mouse thymic lymphomas. A direct regulation of Notch1 on HMGA1 transcription was demonstrated and two Notch1/RBPJ cobinding sites of T/CTCCCACA were found in HMGA1 promoter regions. It was the first time demonstrated that HMGA1 was the downstream target of Notch1 signaling. Moreover, knockdown of HMGA1 resulted in significantly impaired cell growth and decreased expressions of cyclin D and cyclin E in human T leukemia cells. The formation of complexes was also observed between HMGA1 and retinoblastoma (RB) protein indicating a mechanism of cell cycle regulation. These findings suggest that activated HMGA1 regulates cell proliferation through the Notch1 signaling pathway, which represents an important molecular pathway leading to leukemogenesis.
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Affiliation(s)
- Yang Xi
- Medical School, Ningbo University, Ningbo, 315211, China
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Bagley BN, Keane TM, Maklakova VI, Marshall JG, Lester RA, Cancel MM, Paulsen AR, Bendzick LE, Been RA, Kogan SC, Cormier RT, Kendziorski C, Adams DJ, Collier LS. A dominantly acting murine allele of Mcm4 causes chromosomal abnormalities and promotes tumorigenesis. PLoS Genet 2012; 8:e1003034. [PMID: 23133403 PMCID: PMC3486839 DOI: 10.1371/journal.pgen.1003034] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Accepted: 08/29/2012] [Indexed: 12/22/2022] Open
Abstract
Here we report the isolation of a murine model for heritable T cell lymphoblastic leukemia/lymphoma (T-ALL) called Spontaneous dominant leukemia (Sdl). Sdl heterozygous mice develop disease with a short latency and high penetrance, while mice homozygous for the mutation die early during embryonic development. Sdl mice exhibit an increase in the frequency of micronucleated reticulocytes, and T-ALLs from Sdl mice harbor small amplifications and deletions, including activating deletions at the Notch1 locus. Using exome sequencing it was determined that Sdl mice harbor a spontaneously acquired mutation in Mcm4 (Mcm4D573H). MCM4 is part of the heterohexameric complex of MCM2–7 that is important for licensing of DNA origins prior to S phase and also serves as the core of the replicative helicase that unwinds DNA at replication forks. Previous studies in murine models have discovered that genetic reductions of MCM complex levels promote tumor formation by causing genomic instability. However, Sdl mice possess normal levels of Mcms, and there is no evidence for loss-of-heterozygosity at the Mcm4 locus in Sdl leukemias. Studies in Saccharomyces cerevisiae indicate that the Sdl mutation produces a biologically inactive helicase. Together, these data support a model in which chromosomal abnormalities in Sdl mice result from the ability of MCM4D573H to incorporate into MCM complexes and render them inactive. Our studies indicate that dominantly acting alleles of MCMs can be compatible with viability but have dramatic oncogenic consequences by causing chromosomal abnormalities. Our study investigated a spontaneous mouse model for dominantly inherited T-cell leukemia/lymphoma. Using genetic methods, we identified a mutant allele of Mcm4 (Mcm4D573H) in this model. Interestingly, this Mcm4 allele promotes the accumulation of focal chromosomal gains and losses, including aberrations at the Notch1 locus that drive the formation of T-cell leukemia/lymphoma. Previous studies of hypomorphic Mcm alleles have demonstrated that a decrease in MCM levels can cause tumorigenesis. However, total and chromatin bound MCM levels were similar to wild-type in our model, indicating that Mcm alleles that do not drastically impact MCM levels can cause genomic aberrations that drive tumor formation.
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Affiliation(s)
- Bruce N. Bagley
- School of Pharmacy and UW Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, United States of America
| | - Thomas M. Keane
- Experimental Cancer Genetics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Vilena I. Maklakova
- School of Pharmacy and UW Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, United States of America
| | - Jonathon G. Marshall
- School of Pharmacy and UW Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, United States of America
| | - Rachael A. Lester
- School of Pharmacy and UW Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, United States of America
| | - Michelle M. Cancel
- School of Pharmacy and UW Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, United States of America
| | - Alex R. Paulsen
- School of Pharmacy and UW Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, United States of America
| | - Laura E. Bendzick
- Department of Genetics, Cell Biology, and Development, Masonic Cancer Center, University of Minnesota Twin Cities, Minneapolis, Minnesota, United States of America
| | - Raha A. Been
- Department of Genetics, Cell Biology, and Development, Masonic Cancer Center, University of Minnesota Twin Cities, Minneapolis, Minnesota, United States of America
| | - Scott C. Kogan
- Department of Laboratory Medicine and Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, California, United States of America
| | - Robert T. Cormier
- Department of Biomedical Sciences, University of Minnesota Medical School Duluth, Duluth, Minnesota, United States of America
| | - Christina Kendziorski
- Department of Biostatistics and Medical Informatics and UW Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, United States of America
| | - David J. Adams
- Experimental Cancer Genetics, Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, United Kingdom
| | - Lara S. Collier
- School of Pharmacy and UW Carbone Cancer Center, University of Wisconsin Madison, Madison, Wisconsin, United States of America
- * E-mail:
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Blackburn JS, Liu S, Raiser DM, Martinez SA, Feng H, Meeker ND, Gentry J, Neuberg D, Look AT, Ramaswamy S, Bernards A, Trede NS, Langenau DM. Notch signaling expands a pre-malignant pool of T-cell acute lymphoblastic leukemia clones without affecting leukemia-propagating cell frequency. Leukemia 2012; 26:2069-78. [PMID: 22538478 PMCID: PMC3435461 DOI: 10.1038/leu.2012.116] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2011] [Revised: 04/03/2012] [Accepted: 04/18/2012] [Indexed: 01/22/2023]
Abstract
NOTCH1 pathway activation contributes to the pathogenesis of over 60% of T-cell acute lymphoblastic leukemia (T-ALL). While Notch is thought to exert the majority of its effects through transcriptional activation of Myc, it also likely has independent roles in T-ALL malignancy. Here, we utilized a zebrafish transgenic model of T-ALL, where Notch does not induce Myc transcription, to identify a novel Notch gene expression signature that is also found in human T-ALL and is regulated independently of Myc. Cross-species microarray comparisons between zebrafish and mammalian disease identified a common T-ALL gene signature, suggesting that conserved genetic pathways underlie T-ALL development. Functionally, Notch expression induced a significant expansion of pre-leukemic clones; however, a majority of these clones were not fully transformed and could not induce leukemia when transplanted into recipient animals. Limiting-dilution cell transplantation revealed that Notch signaling does not increase the overall frequency of leukemia-propagating cells (LPCs), either alone or in collaboration with Myc. Taken together, these data indicate that a primary role of Notch signaling in T-ALL is to expand a population of pre-malignant thymocytes, of which a subset acquire the necessary mutations to become fully transformed LPCs.
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Affiliation(s)
- Jessica S. Blackburn
- Department of Pathology, Massachusetts General Hospital, Boston, MA
- Center of Cancer Research, Massachusetts General Hospital, Charlestown, MA
- Harvard Stem Cell Institute, Boston, MA
| | - Sali Liu
- Department of Pathology, Massachusetts General Hospital, Boston, MA
- Center of Cancer Research, Massachusetts General Hospital, Charlestown, MA
- Harvard Stem Cell Institute, Boston, MA
| | | | - Sarah A. Martinez
- Department of Pathology, Massachusetts General Hospital, Boston, MA
- Center of Cancer Research, Massachusetts General Hospital, Charlestown, MA
- Harvard Stem Cell Institute, Boston, MA
| | - Hui Feng
- Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA
| | - Nathan D. Meeker
- Department of Pediatrics, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT
| | - Jeffery Gentry
- Center of Cancer Research, Massachusetts General Hospital, Charlestown, MA
| | - Donna Neuberg
- Department of Biostatistics, Dana-Farber Cancer Institute, Boston, MA
| | - A. Thomas Look
- Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA
| | - Sridhar Ramaswamy
- Center of Cancer Research, Massachusetts General Hospital, Charlestown, MA
- Harvard Stem Cell Institute, Boston, MA
| | - Andre Bernards
- Center of Cancer Research, Massachusetts General Hospital, Charlestown, MA
| | - Nikolaus S. Trede
- Department of Pediatrics, Huntsman Cancer Institute, University of Utah, Salt Lake City, UT
| | - David M. Langenau
- Department of Pathology, Massachusetts General Hospital, Boston, MA
- Center of Cancer Research, Massachusetts General Hospital, Charlestown, MA
- Harvard Stem Cell Institute, Boston, MA
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Enforced expression of Lin28b leads to impaired T-cell development, release of inflammatory cytokines, and peripheral T-cell lymphoma. Blood 2012; 120:1048-59. [PMID: 22723554 DOI: 10.1182/blood-2012-01-401760] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
LIN28A and LIN28B, the mammalian homologs of lin-28, are implicated in malignant transformation in part because of their ability to promote degradation of the let-7 family of miRs. In the present study, we show that overexpression of Lin28b in vivo leads to an aggressive peripheral T-cell lymphoma (PTCL) characterized by widespread infiltration of parenchymal organs with malignant CD4(+) cells. Similar to patients with PTCL, Lin28b-transgenic mice show signs of inflammation such as eosinophilia, increased C-reactive protein, release of inflammatory cytokines, and pleural effusion. The PTCLs that develop in Lin28b mice are derived from activated T cells and show decreased let-7 expression, increased Il6 expression, activation of NF-κB, and infiltration of B cells, all resulting in an inflammatory microenvironment. In addition, LIN28B is overexpressed 7.5-fold in PTCL patient samples compared with activated CD4(+) cells. The results of the present study demonstrate for the first time that Lin28b can transform primary cells in vivo, identify a previously unsuspected link between Lin28b and PTCL, and provide a unique animal model for the study of PTCL biology and therapy.
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Onozawa M, Aplan PD. Illegitimate V(D)J recombination involving nonantigen receptor loci in lymphoid malignancy. Genes Chromosomes Cancer 2012; 51:525-35. [PMID: 22334400 PMCID: PMC3323722 DOI: 10.1002/gcc.21942] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2011] [Accepted: 01/10/2012] [Indexed: 11/09/2022] Open
Abstract
V(D)J recombination of antigen receptor loci (IGH, IGK, IGL, TCRA, TCRB, TCRG, and TCRD) is an essential mechanism that confers enormous diversity to the mammalian immune system. However, there are now at least six examples of intrachromosomal interstitial deletions caused by aberrant V(D)J recombination between nonantigen receptor loci; five of out these six are associated with lymphoid malignancy. The SIL-SCL fusion and deletions of CDKN2A, IKZF1, Notch1, and Bcl11b are all associated with lymphoid malignancy. These interstitial deletions seem to be species specific, as the deletions seen in mice are not seen in humans; the converse is true as well. Nucleotide sequence analysis of these rearrangements reveals the hallmarks of V(D)J recombination, including site specificity near cryptic heptamer signal sequences, exonucleolytic "nibbling" at the junction site, and nontemplated "N"-region nucleotide insertion at the junction site. Two of these interstitial deletions (murine Notch1 and Bcl11b deletions) have been detected, at low frequency, in tissues from healthy mice with no evidence of malignancy, similar to the finding of chromosomal translocations in the peripheral blood or tonsils of healthy individuals. The contention that these are mediated via V(D)J recombination is strengthened by in vivo assays using extrachromosomal substrates, and chromatin immunoprecipitation-sequence analysis which shows Rag2 binding at the sites of rearrangement. Although the efficiency of these "illegitimate" recombination events is several orders of magnitude less than that at bona fide antigen receptor loci, the consequence of such deletions, namely activation of proto-oncogenes or deletion of tumor suppressor genes, is devastating, and a major cause for lymphoid malignancy.
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Affiliation(s)
- Masahiro Onozawa
- Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institute of Health, Bethesda, MD
| | - Peter D. Aplan
- Genetics Branch, Center for Cancer Research, National Cancer Institute, National Institute of Health, Bethesda, MD
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Abstract
Oncogenic activating mutations in NOTCH1 occur in more than 50% of T-cell acute lymphoblastic leukemias (T-ALLs). In the present study, we describe a novel mechanism of NOTCH1 activation in T-ALL in which a deletion removing the 5' portion of NOTCH1 abolishes the negative regulatory control of the extracellular domain and leads to constitutively active NOTCH1 signaling. Polypeptides translated from truncated transcripts encoded by the NOTCH1 deletion allele retain the transmembrane domain of the receptor and are constitutively cleaved by the γ-secretase complex, resulting in high levels of NOTCH1 signaling that can be effectively blocked by γ-secretase inhibitors. Our results expand the spectrum of oncogenic lesions activating NOTCH1 signaling in human T-ALL.
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50
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Wang HC, Peng V, Zhao Y, Sun XH. Enhanced Notch activation is advantageous but not essential for T cell lymphomagenesis in Id1 transgenic mice. PLoS One 2012; 7:e32944. [PMID: 22393458 PMCID: PMC3290631 DOI: 10.1371/journal.pone.0032944] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 02/02/2012] [Indexed: 01/06/2023] Open
Abstract
T cell lymphoblastic leukemia (T-ALL) is known to be associated with chromosomal abnormalities that lead to aberrant expression of a number of transcription factors such as TAL1, which dimerizes with basic helix-loop-helix (bHLH) E proteins and inhibits their function. Activated Notch receptors also efficiently induce T cell leukemogenesis in mouse models. Interestingly, gain-of-function mutations or cryptic transcription initiation of the Notch1 gene have been frequently found in both human and mouse T-ALL. However, the correlations between these alterations and overall Notch activities or leukemogenesis have not been thoroughly evaluated. Therefore, we made use of our collection of T cell lymphomas developed in transgenic mice expressing Id1, which like TAL1, inhibits E protein function. By comparing expression levels of Notch target genes in Id1-expressing tumors to those in tumors induced by a constitutively active form of Notch1, N1C, we were able to assess the overall activities of Notch pathways and conclude that the majority of Id1-expressing tumors had elevated Notch function to a varying degree. However, 26% of the Id1-expressing tumors had no evidence of enhanced Notch activation, but that did not delay the onset of tumorigenesis. Furthermore, we examined the genetic or epigenetic alterations thought to contribute to ligand-independent activation or protein stabilization of Notch1 and found that some of the Id1-expressing tumors acquired these changes, but they are not uniformly associated with elevated Notch activities in Id1 tumor samples. In contrast, N1C-expressing tumors do not harbor any PEST domain mutations nor exhibit intragenic transcription initiation. Taken together, it appears that Notch activation provides Id1-expressing tumor cells with selective advantages in growth and survival. However, this may not be absolutely essential for lymphomagenesis in Id1 transgenic mice and additional factors could also cooperate with Id1 to induce T cell lymphoma. Therefore, a broad approach is necessary in designing T-ALL therapy.
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Affiliation(s)
- Hong-Cheng Wang
- Immunobiology and Cancer Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
| | - Vincent Peng
- Oklahoma School of Science and Mathematics, Oklahoma City, Oklahoma, United States of America
| | - Ying Zhao
- Immunobiology and Cancer Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
| | - Xiao-Hong Sun
- Immunobiology and Cancer Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, United States of America
- * E-mail:
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