1
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Focused CRISPR-Cas9 genetic screening reveals USO1 as a vulnerability in B-cell acute lymphoblastic leukemia. Sci Rep 2021; 11:13158. [PMID: 34162911 PMCID: PMC8222245 DOI: 10.1038/s41598-021-92448-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2020] [Accepted: 06/10/2021] [Indexed: 12/13/2022] Open
Abstract
Post-transcriptional gene regulation, including that by RNA binding proteins (RBPs), has recently been described as an important mechanism in cancer. We had previously identified a set of RBPs that were highly dysregulated in B-cell acute lymphoblastic leukemia (B-ALL) with MLL translocations, which carry a poor prognosis. Here, we sought to functionally characterize these dysregulated RBP genes by performing a focused CRISPR dropout screen in B-ALL cell lines, finding dependencies on several genes including EIF3E, EPRS and USO1. Validating our findings, CRISPR/Cas9-mediated disruption of USO1 in MLL-translocated B-ALL cells reduced cell growth, promoted cell death, and altered the cell cycle. Transcriptomic analysis of USO1-deficient cells revealed alterations in pathways related to mTOR signaling, RNA metabolism, and targets of MYC. In addition, USO1-regulated genes from these experimental samples were significantly and concordantly correlated with USO1 expression in primary samples collected from B-ALL patients. Lastly, we found that loss of Uso1 inhibited colony formation of MLL-transformed in primary bone marrow cells from Cas9-EGFP mice. Together, our findings demonstrate an approach to performing focused sub-genomic CRISPR screens and highlight a putative RBP vulnerability in MLL-translocated B-ALL, thus identifying potential therapeutic targets in this disease.
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2
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Sugeedha J, Gautam J, Tyagi S. SET1/MLL family of proteins: functions beyond histone methylation. Epigenetics 2020; 16:469-487. [PMID: 32795105 PMCID: PMC8078731 DOI: 10.1080/15592294.2020.1809873] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The SET1 family of enzymes are well known for their involvement in the histone 3 lysine 4 (H3K4) methylation, a conserved trait of euchromatin associated with transcriptional activation. These methyltransferases are distinct, and involved in various biological functions in the cell. Impairment in the function of SET1 family members leads to a number of abnormalities such as skeletal and neurological defects, leukaemogenesis and even lethality. Tremendous progress has been made in understanding the unique biological roles and the mechanism of SET1 enzymes in context with H3K4 methylation/canonical functions. However, in recent years, several studies have indicated the novel role of SET1 family proteins, other than H3K4 methylation, which are equally important for cellular functions. In this review, we focus on these non-canonical function of SET1 family members.
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Affiliation(s)
- Jeyapal Sugeedha
- Laboratory of Cell Cycle Regulation, Centre for DNA Fingerprinting and Diagnostics (CDFD), Uppal, Hyderabad, India
| | - Jyoti Gautam
- Laboratory of Cell Cycle Regulation, Centre for DNA Fingerprinting and Diagnostics (CDFD), Uppal, Hyderabad, India
| | - Shweta Tyagi
- Laboratory of Cell Cycle Regulation, Centre for DNA Fingerprinting and Diagnostics (CDFD), Uppal, Hyderabad, India
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3
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Ge M, Li D, Qiao Z, Sun Y, Kang T, Zhu S, Wang S, Xiao H, Zhao C, Shen S, Xu Z, Liu H. Restoring MLL reactivates latent tumor suppression-mediated vulnerability to proteasome inhibitors. Oncogene 2020; 39:5888-5901. [PMID: 32733069 PMCID: PMC7471105 DOI: 10.1038/s41388-020-01408-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 07/16/2020] [Accepted: 07/23/2020] [Indexed: 12/15/2022]
Abstract
MLL undergoes multiple distinct chromosomal translocations to yield aggressive leukemia with dismal outcomes. Besides their well-established role in leukemogenesis, MLL fusions also possess latent tumor-suppressive activity, which can be exploited as effective cancer treatment strategies using pharmacological means such as proteasome inhibitors (PIs). Here, using MLL-rearranged xenografts and MLL leukemic cells as models, we show that wild-type MLL is indispensable for the latent tumor-suppressive activity of MLL fusions. MLL dysfunction, shown as loss of the chromatin accumulation and subsequent degradation of MLL, compromises the latent tumor suppression of MLL-AF4 and is instrumental for the acquired PI resistance. Mechanistically, MLL dysfunction is caused by chronic PI treatment-induced epigenetic reprogramming through the H2Bub-ASH2L-MLL axis and can be specifically restored by histone deacetylase (HDAC) inhibitors, which induce histone acetylation and recruits MLL on chromatin to promote cell cycle gene expression. Our findings not only demonstrate the mechanism underlying the inevitable acquisition of PI resistance in MLL leukemic cells, but also illustrate that preventing the emergence of PI-resistant cells constitutes a novel rationale for combination therapy with PIs and HDAC inhibitors in MLL leukemias.
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Affiliation(s)
- Maolin Ge
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Dan Li
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Zhi Qiao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - Yan Sun
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Ting Kang
- Department of Oncology, Xin Hua Hospital, School of Medicine, Shanghai Jiao Tong University, 200092, Shanghai, China
| | - Shouhai Zhu
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Shifen Wang
- Fujian Institute of Hematology, Fujian Provincial Key Laboratory of Hematology, Fujian Medical University Union Hospital, 350001, Fuzhou, China
| | - Hua Xiao
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 200240, Shanghai, China
| | - Chunjun Zhao
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China
| | - Shuhong Shen
- Key Laboratory of Pediatric Hematology and Oncology Ministry of Health, Department of Hematology & Oncology, Pediatric Translational Medicine Institute, Shanghai Children's Medical Center, School of Medicine, Shanghai Jiao Tong University, 200127, Shanghai, China.
| | - Zhenshu Xu
- Fujian Institute of Hematology, Fujian Provincial Key Laboratory of Hematology, Fujian Medical University Union Hospital, 350001, Fuzhou, China.
| | - Han Liu
- Shanghai Institute of Hematology, State Key Laboratory of Medical Genomics, National Research Center for Translational Medicine at Shanghai, Ruijin Hospital affiliated to Shanghai Jiao Tong University School of Medicine, 200025, Shanghai, China.
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4
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Schwaller J. Learning from mouse models of MLL fusion gene-driven acute leukemia. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1863:194550. [PMID: 32320749 DOI: 10.1016/j.bbagrm.2020.194550] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 02/17/2020] [Accepted: 04/05/2020] [Indexed: 01/28/2023]
Abstract
5-10% of human acute leukemias carry chromosomal translocations involving the mixed lineage leukemia (MLL) gene that result in the expression of chimeric protein fusing MLL to >80 different partners of which AF4, ENL and AF9 are the most prevalent. In contrast to many other leukemia-associated mutations, several MLL-fusions are powerful oncogenes that transform hematopoietic stem cells but also more committed progenitor cells. Here, I review different approaches that were used to express MLL fusions in the murine hematopoietic system which often, but not always, resulted in highly penetrant and transplantable leukemias that closely phenocopied the human disease. Due to its simple and reliable nature, reconstitution of irradiated mice with bone marrow cells retrovirally expressing the MLL-AF9 fusion became the most frequently in vivo model to study the biology of acute myeloid leukemia (AML). I review some of the most influential studies that used this model to dissect critical protein interactions, the impact of epigenetic regulators, microRNAs and microenvironment-dependent signals for MLL fusion-driven leukemia. In addition, I highlight studies that used this model for shRNA- or genome editing-based screens for cellular vulnerabilities that allowed to identify novel therapeutic targets of which some entered clinical trials. Finally, I discuss some inherent characteristics of the widely used mouse model based on retroviral expression of the MLL-AF9 fusion that can limit general conclusions for the biology of AML. This article is part of a Special Issue entitled: The MLL family of proteins in normal development and disease edited by Thomas A Milne.
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Affiliation(s)
- Juerg Schwaller
- University Children's Hospital Beider Basel (UKBB), Basel, Switzerland; Department of Biomedicine, University of Basel, Switzerland.
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5
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Hematopoietic stem and progenitor cell proliferation and differentiation requires the trithorax protein Ash2l. Sci Rep 2019; 9:8262. [PMID: 31164666 PMCID: PMC6547667 DOI: 10.1038/s41598-019-44720-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 05/20/2019] [Indexed: 12/18/2022] Open
Abstract
Post-translational modifications of core histones participate in controlling the expression of genes. Methylation of lysine 4 of histone H3 (H3K4), together with acetylation of H3K27, is closely associated with open chromatin and gene transcription. H3K4 methylation is catalyzed by KMT2 lysine methyltransferases that include the mixed-lineage leukemia 1–4 (MLL1-4) and SET1A and B enzymes. For efficient catalysis, all six require a core complex of four proteins, WDR5, RBBP5, ASH2L, and DPY30. We report that targeted disruption of Ash2l in the murine hematopoietic system results in the death of the mice due to a rapid loss of mature hematopoietic cells. However, lin−Sca1+Kit+ (LSK) cells, which are highly enriched in hematopoietic stem and multi-potent progenitor cells, accumulated in the bone marrow. The loss of Ash2l resulted in global reduction of H3K4 methylation and deregulated gene expression, including down-regulation of many mitosis-associated genes. As a consequence, LSK cells accumulated in the G2-phase of the cell cycle and were unable to proliferate and differentiate. In conclusion, Ash2l is essential for balanced gene expression and for hematopoietic stem and multi-potent progenitor cell physiology.
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Glucocorticoid-resistant B cell acute lymphoblastic leukemia displays receptor tyrosine kinase activation. NPJ Genom Med 2019; 4:7. [PMID: 30962949 PMCID: PMC6449402 DOI: 10.1038/s41525-019-0082-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 03/13/2019] [Indexed: 01/29/2023] Open
Abstract
The response of childhood acute lymphoblastic leukemia (ALL) to dexamethasone predicts the long-term remission outcome. To explore the mechanisms of dexamethasone resistance in B cell ALL (B-ALL), we generated dexamethasone-resistant clones by prolonged treatment with dexamethasone. Using RNA-sequencing and high-throughput screening, we found that dexamethasone-resistant cells are dependent on receptor tyrosine kinases. Further analysis with phosphokinase arrays showed that the type III receptor tyrosine kinase FLT3 is constitutively active in resistant cells. Targeted next-generation and Sanger sequencing identified an internal tandem duplication mutation and a point mutation (R845G) in FLT3 in dexamethasone-resistant cells, which were not present in the corresponding sensitive clones. Finally, we showed that resistant cells displayed sensitivity to second-generation FLT3 inhibitors both in vitro and in vivo. Collectively, our data suggest that long-term dexamethasone treatment selects cells with a distinct genetic background, in this case oncogenic FLT3, and therefore therapies targeting FLT3 might be useful for the treatment of relapsed B-ALL patients.
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7
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Grey W, Ivey A, Milne TA, Haferlach T, Grimwade D, Uhlmann F, Voisset E, Yu V. The Cks1/Cks2 axis fine-tunes Mll1 expression and is crucial for MLL-rearranged leukaemia cell viability. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2018; 1865:105-116. [PMID: 28939057 PMCID: PMC5701546 DOI: 10.1016/j.bbamcr.2017.09.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 09/09/2017] [Accepted: 09/17/2017] [Indexed: 12/25/2022]
Abstract
The Cdc28 protein kinase subunits, Cks1 and Cks2, play dual roles in Cdk-substrate specificity and Cdk-independent protein degradation, in concert with the E3 ubiquitin ligase complexes SCFSkp2 and APCCdc20. Notable targets controlled by Cks include p27 and Cyclin A. Here, we demonstrate that Cks1 and Cks2 proteins interact with both the MllN and MllC subunits of Mll1 (Mixed-lineage leukaemia 1), and together, the Cks proteins define Mll1 levels throughout the cell cycle. Overexpression of CKS1B and CKS2 is observed in multiple human cancers, including various MLL-rearranged (MLLr) AML subtypes. To explore the importance of MLL-Fusion Protein regulation by CKS1/2, we used small molecule inhibitors (MLN4924 and C1) to modulate their protein degradation functions. These inhibitors specifically reduced the proliferation of MLLr cell lines compared to primary controls. Altogether, this study uncovers a novel regulatory pathway for MLL1, which may open a new therapeutic approach to MLLr leukaemia.
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Affiliation(s)
- William Grey
- Department of Medical and Molecular Genetics, King's College London, Faculty of Life Sciences and Medicine, London, UK.
| | - Adam Ivey
- Department of Medical and Molecular Genetics, King's College London, Faculty of Life Sciences and Medicine, London, UK
| | - Thomas A Milne
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, NIHR Oxford Biomedical Research Centre Programme, University of Oxford, UK
| | | | - David Grimwade
- Department of Medical and Molecular Genetics, King's College London, Faculty of Life Sciences and Medicine, London, UK
| | - Frank Uhlmann
- Chromosome Segregation Laboratory, The Francis Crick Institute, London, UK
| | - Edwige Voisset
- Department of Medical and Molecular Genetics, King's College London, Faculty of Life Sciences and Medicine, London, UK.
| | - Veronica Yu
- Department of Medical and Molecular Genetics, King's College London, Faculty of Life Sciences and Medicine, London, UK
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8
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Vedadi M, Blazer L, Eram MS, Barsyte-Lovejoy D, Arrowsmith CH, Hajian T. Targeting human SET1/MLL family of proteins. Protein Sci 2017; 26:662-676. [PMID: 28160335 PMCID: PMC5368065 DOI: 10.1002/pro.3129] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 01/18/2017] [Accepted: 01/24/2017] [Indexed: 12/15/2022]
Abstract
The SET1 family of proteins, and in particular MLL1, are essential regulators of transcription and key mediators of normal development and disease. Here, we summarize the detailed characterization of the methyltransferase activity of SET1 complexes and the role of the key subunits, WDR5, RbBP5, ASH2L, and DPY30. We present new data on full kinetic characterization of human MLL1, MLL3, SET1A, and SET1B trimeric, tetrameric, and pentameric complexes to elaborate on substrate specificities and compare our findings with what has been reported before. We also review exciting recent work identifying potent inhibitors of oncogenic MLL1 function through disruption of protein–protein interactions within the MLL1 complex.
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Affiliation(s)
- Masoud Vedadi
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7.,Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, M5S 1A8
| | - Levi Blazer
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7
| | - Mohammad S Eram
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7
| | | | - Cheryl H Arrowsmith
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7.,Princess Margaret Cancer Centre and Department of Medical Biophysics, University of Toronto, Toronto, ON, M5G 2M9
| | - Taraneh Hajian
- Structural Genomics Consortium, University of Toronto, Toronto, ON, M5G 1L7
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9
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Yang W, Tran P, Khan Z, Rezk S, O'Brien S. MLL-rearranged mixed phenotype acute leukemia masquerading as B-cell ALL. Leuk Lymphoma 2016; 58:1498-1501. [PMID: 27774846 DOI: 10.1080/10428194.2016.1246728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Affiliation(s)
- Wei Yang
- a Department of Medicine , University of California Irvine , Orange , CA , USA
| | - Phu Tran
- b Division of Hematology-Oncology , University of California Irvine , Orange , CA , USA
| | - Ziad Khan
- b Division of Hematology-Oncology , University of California Irvine , Orange , CA , USA
| | - Sherif Rezk
- c Department of Pathology and Laboratory Medicine , University of California Irvine , Orange , CA , USA
| | - Susan O'Brien
- b Division of Hematology-Oncology , University of California Irvine , Orange , CA , USA
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10
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Yeh CH, Moles R, Nicot C. Clinical significance of microRNAs in chronic and acute human leukemia. Mol Cancer 2016; 15:37. [PMID: 27179712 PMCID: PMC4867976 DOI: 10.1186/s12943-016-0518-2] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/01/2016] [Indexed: 01/01/2023] Open
Abstract
Small non-coding microRNAs (miRNAs) are epigenetic regulators that target specific cellular mRNA to modulate gene expression patterns and cellular signaling pathways. miRNAs are involved in a wide range of biological processes and are frequently deregulated in human cancers. Numerous miRNAs promote tumorigenesis and cancer progression by enhancing tumor growth, angiogenesis, invasion and immune evasion, while others have tumor suppressive effects (Hayes, et al., Trends Mol Med 20(8): 460-9, 2014; Stahlhut and Slack, Genome Med 5 (12): 111, 2013). The expression profile of cancer miRNAs can be used to predict patient prognosis and clinical response to treatment (Bouchie, Nat Biotechnol 31(7): 577, 2013). The majority of miRNAs are intracellular localized, however circulating miRNAs have been detected in various body fluids and represent new biomarkers of solid and hematologic cancers (Fabris and Calin, Mol Oncol 10(3):503-8, 2016; Allegra, et al., Int J Oncol 41(6): 1897-912, 2012). This review describes the clinical relevance of miRNAs, lncRNAs and snoRNAs in the diagnosis, prognosis and treatment response in patients with chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), acute lymphocytic leukemia (ALL), acute myeloid leukemia (AML) and acute adult T-cell leukemia (ATL).
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Affiliation(s)
- Chien-Hung Yeh
- Department of Pathology, Center for Viral Oncology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA
| | - Ramona Moles
- Department of Pathology, Center for Viral Oncology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA
| | - Christophe Nicot
- Department of Pathology, Center for Viral Oncology, University of Kansas Medical Center, 3901 Rainbow Boulevard, Kansas City, KS 66160, USA.
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11
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Abstract
Histone-lysine N-methyltransferase 2 (KMT2) family proteins methylate lysine 4 on the histone H3 tail at important regulatory regions in the genome and thereby impart crucial functions through modulating chromatin structures and DNA accessibility. Although the human KMT2 family was initially named the mixed-lineage leukaemia (MLL) family, owing to the role of the first-found member KMT2A in this disease, recent exome-sequencing studies revealed KMT2 genes to be among the most frequently mutated genes in many types of human cancers. Efforts to integrate the molecular mechanisms of KMT2 with its roles in tumorigenesis have led to the development of first-generation inhibitors of KMT2 function, which could become novel cancer therapies.
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Affiliation(s)
- Rajesh C. Rao
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
- Department of Ophthalmology & Visual Sciences, University of Michigan, Ann Arbor, MI 48109
| | - Yali Dou
- Department of Pathology, University of Michigan, Ann Arbor, MI 48109
- Department of Biological Chemistry, University of Michigan, Ann Arbor, MI 48109
- Correspondence: , Tel: (734) 6151315, Fax: (734) 7636476
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12
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Aguilera CM, Gomez-Llorente C, Tofe I, Gil-Campos M, Cañete R, Gil Á. Genome-wide expression in visceral adipose tissue from obese prepubertal children. Int J Mol Sci 2015; 16:7723-37. [PMID: 25856673 PMCID: PMC4425045 DOI: 10.3390/ijms16047723] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 03/19/2015] [Accepted: 04/01/2015] [Indexed: 02/07/2023] Open
Abstract
Characterization of the genes expressed in adipose tissue (AT) is key to understanding the pathogenesis of obesity and to developing treatments for this condition. Our objective was to compare the gene expression in visceral AT (VAT) between obese and normal-weight prepubertal children. A total of fifteen obese and sixteen normal-weight children undergoing abdominal elective surgery were selected. RNA was extracted from VAT biopsies. Microarray experiments were independently performed for each sample (six obese and five normal-weight samples). Validation by quantitative PCR (qPCR) was performed on an additional 10 obese and 10 normal-weight VAT samples. Of 1276 differentially expressed genes (p < 0.05), 245 were more than two-fold higher in obese children than in normal-weight children. As validated by qPCR, expression was upregulated in genes involved in lipid and amino acid metabolism (CES1, NPRR3 and BHMT2), oxidative stress and extracellular matrix regulation (TNMD and NQO1), adipogenesis (CRYAB and AFF1) and inflammation (ANXA1); by contrast, only CALCRL gene expression was confirmed to be downregulated. In conclusion, this study in prepubertal children demonstrates the up- and down-regulation of genes that encode molecules that were previously proposed to influence the pathogenesis of adulthood obesity, as well as previously unreported dysregulated genes that may be candidate genes in the aetiology of obesity.
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Affiliation(s)
- Concepción M Aguilera
- Department of Biochemistry and Molecular Biology II, Institute of Nutrition and Food Technology, Centre for Biomedical Research, University of Granada, Armilla, 18100 Granada, Spain.
| | - Carolina Gomez-Llorente
- Department of Biochemistry and Molecular Biology II, Institute of Nutrition and Food Technology, Centre for Biomedical Research, University of Granada, Armilla, 18100 Granada, Spain.
| | - Inés Tofe
- Unit of Pediatric Endocrinology, Reina Sofia University Hospital, Avda Menéndez Pidal s/n. 14004 Córdoba, Spain.
| | - Mercedes Gil-Campos
- Unit of Pediatric Endocrinology, Reina Sofia University Hospital, Avda Menéndez Pidal s/n. 14004 Córdoba, Spain.
| | - Ramón Cañete
- Unit of Pediatric Endocrinology, Reina Sofia University Hospital, Avda Menéndez Pidal s/n. 14004 Córdoba, Spain.
| | - Ángel Gil
- Department of Biochemistry and Molecular Biology II, Institute of Nutrition and Food Technology, Centre for Biomedical Research, University of Granada, Armilla, 18100 Granada, Spain.
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13
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Roy A, Banerjee S. p27 and Leukemia: Cell Cycle and Beyond. J Cell Physiol 2014; 230:504-9. [PMID: 25205053 DOI: 10.1002/jcp.24819] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2014] [Accepted: 09/05/2014] [Indexed: 01/17/2023]
Affiliation(s)
- Anita Roy
- Biophysics and Structural Genomics Division; Saha Institute of Nuclear Physics; 1/AF Bidhannagar Kolkata West Bengal India
| | - Subrata Banerjee
- Biophysics and Structural Genomics Division; Saha Institute of Nuclear Physics; 1/AF Bidhannagar Kolkata West Bengal India
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14
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Wang X, Ju L, Fan J, Zhu Y, Liu X, Zhu K, Wu M, Li L. Histone H3K4 methyltransferase Mll1 regulates protein glycosylation and tunicamycin-induced apoptosis through transcriptional regulation. BIOCHIMICA ET BIOPHYSICA ACTA 2014; 1843:2592-602. [PMID: 24983772 DOI: 10.1016/j.bbamcr.2014.06.013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 06/20/2014] [Accepted: 06/23/2014] [Indexed: 01/03/2023]
Abstract
Disrupting protein glycosylation induces ER (endoplasmic reticulum) stress, resulting in the activation of UPR (unfolded protein response) pathways. A key function of the UPR is to restore ER homeostasis, but prolonged or unsolved ER stress can lead to apoptosis. MLL1 (Mixed Lineage Leukemia 1, also named ALL-1 or HRX), a histone H3K4 methyltransferase in mammals, plays important roles in leukemogenesis, transcriptional regulation, cell cycle and development. Here, we find that Mll1 deficiency enhances UPR and apoptosis induced by the glycosylation inhibitor TM (tunicamycin). The abnormal regulation of the UPR appears to be caused by a defect in protein glycosylation. Furthermore, Mll1 directly binds to the promoters of H6pd, Galnt12 and Ugp2, which regulates H3K4 trimethylation and the subsequent expression of these genes. The knockdown of H6pd, Galnt12 or Ugp2 enhances TM-induced apoptosis in Mll1(+/+)MEF cells, whereas the ectopic expression of these proteins inhibits TM-induced apoptosis in Mll1(-/-) MEF cells. Together, our data suggest that the maturation of glycoproteins in the ER is subject to regulation at the epigenetic level by a histone methyltransferase whose abnormality can lead to cancer and developmental defects.
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Affiliation(s)
- Xiang Wang
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Lingao Ju
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Jiadong Fan
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Yuan Zhu
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Xiaolan Liu
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Kun Zhu
- College of Life Sciences, Wuhan University, Wuhan, China
| | - Min Wu
- College of Life Sciences, Wuhan University, Wuhan, China.
| | - Lianyun Li
- College of Life Sciences, Wuhan University, Wuhan, China.
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15
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Chen Y, Chen J, Yu J, Yang G, Temple E, Harbinski F, Gao H, Wilson C, Pagliarini R, Zhou W. Identification of mixed lineage leukemia 1(MLL1) protein as a coactivator of heat shock factor 1(HSF1) protein in response to heat shock protein 90 (HSP90) inhibition. J Biol Chem 2014; 289:18914-27. [PMID: 24831003 DOI: 10.1074/jbc.m114.574053] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Heat shock protein 90 (HSP90) inhibition inhibits cancer cell proliferation through depleting client oncoproteins and shutting down multiple oncogenic pathways. Therefore, it is an attractive strategy for targeting human cancers. Several HSP90 inhibitors, including AUY922 and STA9090, show promising effects in clinical trials. However, the efficacy of HSP90 inhibitors may be limited by heat shock factor 1 (HSF1)-mediated feedback mechanisms. Here, we identify, through an siRNA screen, that the histone H3 lysine 4 methyltransferase MLL1 functions as a coactivator of HSF1 in response to HSP90 inhibition. MLL1 is recruited to the promoters of HSF1 target genes and regulates their expression in response to HSP90 inhibition. In addition, a striking combination effect is observed when MLL1 depletion is combined with HSP90 inhibition in various human cancer cell lines and tumor models. Thus, targeting MLL1 may block a HSF1-mediated feedback mechanism induced by HSP90 inhibition and provide a new avenue to enhance HSP90 inhibitor activity in human cancers.
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Affiliation(s)
| | | | - Jianjun Yu
- the Department of Oncology, Novartis Institutes for Biomedical Research, Emeryville, California 94608
| | | | | | | | - Hui Gao
- From the Departments of Oncology
| | - Christopher Wilson
- Neuroscience, Novartis Institutes for Biomedical Research, Cambridge, Massachusetts 02139 and
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16
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Liu H, Westergard TD, Cashen A, Piwnica-Worms DR, Kunkle L, Vij R, Pham CG, DiPersio J, Cheng EH, Hsieh JJ. Proteasome inhibitors evoke latent tumor suppression programs in pro-B MLL leukemias through MLL-AF4. Cancer Cell 2014; 25:530-42. [PMID: 24735925 PMCID: PMC4097146 DOI: 10.1016/j.ccr.2014.03.008] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Revised: 11/24/2013] [Accepted: 03/10/2014] [Indexed: 01/22/2023]
Abstract
Chromosomal translocations disrupting MLL generate MLL-fusion proteins that induce aggressive leukemias. Unexpectedly, MLL-fusion proteins are rarely observed at high levels, suggesting excessive MLL-fusions may be incompatible with a malignant phenotype. Here, we used clinical proteasome inhibitors, bortezomib and carfilzomib, to reduce the turnover of endogenous MLL-fusions and discovered that accumulated MLL-fusions induce latent, context-dependent tumor suppression programs. Specifically, in MLL pro-B lymphoid, but not myeloid, leukemias, proteasome inhibition triggers apoptosis and cell cycle arrest involving activation cleavage of BID by caspase-8 and upregulation of p27, respectively. Furthermore, proteasome inhibition conferred preliminary benefit to patients with MLL-AF4 leukemia. Hence, feasible strategies to treat cancer-type and oncogene-specific cancers can be improvised through harnessing inherent tumor suppression properties of individual oncogenic fusions.
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Affiliation(s)
- Han Liu
- Human Oncology & Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; State Key Laboratory of Medical Genomics, Shanghai Institute of Hematology, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, China
| | - Todd D Westergard
- Department of Medicine, Washington University, St. Louis, MO 63105, USA
| | - Amanda Cashen
- Department of Medicine, Washington University, St. Louis, MO 63105, USA
| | - David R Piwnica-Worms
- BRIGHT Institute, Molecular Imaging Center, Mallinckrodt Institute of Radiology, Washington University, St. Louis, MO 63105, USA
| | | | - Ravi Vij
- Department of Medicine, Washington University, St. Louis, MO 63105, USA
| | - Can G Pham
- Human Oncology & Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - John DiPersio
- Department of Medicine, Washington University, St. Louis, MO 63105, USA
| | - Emily H Cheng
- Human Oncology & Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Department of Pathology, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY 10065, USA.
| | - James J Hsieh
- Human Oncology & Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Department of Medicine, Weill Cornell Medical College, New York, NY 10065, USA.
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Zhang J, Seet CS, Sun C, Li J, You D, Volk A, Breslin P, Li X, Wei W, Qian Z, Zeleznik-Le NJ, Zhang Z, Zhang J. p27kip1 maintains a subset of leukemia stem cells in the quiescent state in murine MLL-leukemia. Mol Oncol 2013; 7:1069-82. [PMID: 23988911 DOI: 10.1016/j.molonc.2013.07.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Revised: 07/22/2013] [Accepted: 07/31/2013] [Indexed: 12/14/2022] Open
Abstract
MLL (mixed-lineage leukemia)-fusion genes induce the development of leukemia through deregulation of normal MLL target genes, such as HOXA9 and MEIS1. Both HOXA9 and MEIS1 are required for MLL-fusion gene-induced leukemogenesis. Co-expression of HOXA9 and MEIS1 induces acute myeloid leukemia (AML) similar to that seen in mice in which MLL-fusion genes are over-expressed. p27(kip1) (p27 hereafter), a negative regulator of the cell cycle, has also been defined as an MLL target, the expression of which is up-regulated in MLL leukemic cells (LCs). To investigate whether p27 plays a role in the pathogenesis of MLL-leukemia, we examined the effects of p27 deletion (p27(-/-)) on MLL-AF9 (MA9)-induced murine AML development. HOXA9/MEIS1 (H/M)-induced, p27 wild-type (p27(+/+)) and p27(-/-) AML were studied in parallel as controls. We found that LCs from both MA9-AML and H/M-AML can be separated into three fractions, a CD117(-)CD11b(hi) differentiated fraction as well as CD117(+)CD11b(hi) and CD117(+)CD11b(lo), two less differentiated fractions. The CD117(+)CD11b(lo) fraction, comprising only 1-3% of total LCs, expresses higher levels of early hematopoietic progenitor markers but lower levels of mature myeloid cell markers compared to other populations of LCs. p27 is expressed and is required for maintaining the quiescent and drug-resistant states of the CD117(+)CD11b(lo) fraction of MA9-LCs but not of H/M-LCs. p27 deletion significantly compromises the leukemogenic capacity of CD117(+)CD11b(lo) MA9-LCs by reducing the frequency of leukemic stem cells (LSCs) but does not do so in H/M-LCs. In addition, we found that p27 is highly expressed and required for cell cycle arrest in the CD117(-)CD11b(hi) fraction in both types of LCs. Furthermore, we found that c-Myc expression is required for maintaining LCs in an undifferentiated state independently of proliferation. We concluded that p27 represses the proliferation of LCs, which is specifically required for maintaining the quiescent and drug-resistant states of a small subset of MA9-LSCs in collaboration with the differentiation blockage function of c-Myc.
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Affiliation(s)
- Jun Zhang
- Department of Biology, College of Life and Environment Science, Shanghai Normal University, 100 Guilin Road, Shanghai 200234, PR China; Oncology Institute, Cardinal Bernardin Cancer Center and Department of Pathology, Loyola University Chicago, Maywood, IL 60153, United States
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18
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Dobbins SE, Sherborne AL, Ma YP, Bardini M, Biondi A, Cazzaniga G, Lloyd A, Chubb D, Greaves MF, Houlston RS. The silent mutational landscape of infant MLL-AF4 pro-B acute lymphoblastic leukemia. Genes Chromosomes Cancer 2013; 52:954-60. [PMID: 23893660 DOI: 10.1002/gcc.22090] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 06/17/2013] [Indexed: 01/20/2023] Open
Abstract
Over 90% of infants (< 1-year-old) diagnosed with leukemia have pro-B acute lymphoblastic leukemia (ALL) containing the MLL-AF4 fusion. When compared with other forms of paediatric ALL affecting later B-cell differentiation, MLL-AF4 pro-B is associated with a dismal prognosis with a typical 5-year disease-free survival of <20%. MLL-AF4 may be sufficient on its own for leukemogenesis or the gene-fusion product may alternatively predispose transformed cells to global genetic instability, enhancing the acquisition of additional key mutations. To gain insight into the genomic landscape of infant MLL-AF4 pro-B ALL we performed whole genome sequencing of diagnostic leukemic blasts and matched germline samples from three MLL-AF4 pro-B ALL infants. Our analysis revealed few somatic changes (copy number abnormalities, loss of heterozygosity, or single nucleotide variants), demonstrating that only a very small number of mutations are necessary to generate infant MLL-leukemia.
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Affiliation(s)
- Sara E Dobbins
- Molecular and Population Genetics, Division of Genetics and Epidemiology, Institute of Cancer Research, Sutton, Surrey, SM2 5NG, UK
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Wilkinson A, Ballabio E, Geng H, North P, Tapia M, Kerry J, Biswas D, Roeder R, Allis C, Melnick A, de Bruijn M, Milne T. RUNX1 is a key target in t(4;11) leukemias that contributes to gene activation through an AF4-MLL complex interaction. Cell Rep 2013; 3:116-27. [PMID: 23352661 PMCID: PMC3607232 DOI: 10.1016/j.celrep.2012.12.016] [Citation(s) in RCA: 113] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Revised: 11/08/2012] [Accepted: 12/26/2012] [Indexed: 12/22/2022] Open
Abstract
The Mixed Lineage Leukemia (MLL) protein is an important epigenetic regulator required for the maintenance of gene activation during development. MLL chromosomal translocations produce novel fusion proteins that cause aggressive leukemias in humans. Individual MLL fusion proteins have distinct leukemic phenotypes even when expressed in the same cell type, but how this distinction is delineated on a molecular level is poorly understood. Here, we highlight a unique molecular mechanism whereby the RUNX1 gene is directly activated by MLL-AF4 and the RUNX1 protein interacts with the product of the reciprocal AF4-MLL translocation. These results support a mechanism of transformation whereby two oncogenic fusion proteins cooperate by activating a target gene and then modulating the function of its downstream product.
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Affiliation(s)
- Adam C. Wilkinson
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Erica Ballabio
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Huimin Geng
- Departments of Medicine/Hematology and Oncology Division, Weill Medical College of Cornell University, New York, NY, 10065, USA
- Institute for Computational Biomedicine, Weill Medical College of Cornell University, New York, NY, 10065, USA
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Phillip North
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Marta Tapia
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Jon Kerry
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Debabrata Biswas
- Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, NY 10065, USA
| | - Robert G. Roeder
- Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, NY 10065, USA
| | - C. David Allis
- Laboratory of Chromatin Biology and Epigenetics, The Rockefeller University, New York, NY 10065, USA
| | - Ari Melnick
- Departments of Medicine/Hematology and Oncology Division, Weill Medical College of Cornell University, New York, NY, 10065, USA
- Department of Pharmacology, Weill Medical College of Cornell University, New York, NY, 10065, USA
| | - Marella F.T.R. de Bruijn
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
| | - Thomas A. Milne
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, UK
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20
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The Blk pathway functions as a tumor suppressor in chronic myeloid leukemia stem cells. Nat Genet 2012; 44:861-71. [PMID: 22797726 PMCID: PMC3408839 DOI: 10.1038/ng.2350] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2012] [Accepted: 06/15/2012] [Indexed: 12/18/2022]
Abstract
A therapeutic strategy for treating cancer is to target and eradicate cancer stem cells (CSCs) without harming their normal stem cell counterparts. The success of this approach relies on identification of molecular pathways that selectively regulate CSC function. Using BCR-ABL-induced chronic myeloid leukemia (CML) as a disease model for CSCs, we show that BCR-ABL down-regulates the B lymphoid kinase (Blk) gene through c-Myc in leukemia stem cells (LSCs) in CML mice and that Blk functions as a tumor suppressor in LSCs but does not affect normal hematopoietic stem cells (HSCs) or hematopoiesis. Blk suppresses LSC function through a pathway involving an upstream regulator, Pax5, and a downstream effector, p27. Inhibition of this Blk pathway accelerates CML development, whereas increased activity of the Blk pathway delays CML development. Blk also suppresses human CML stem cells. Our results demonstrate the feasibility of selectively targeting LSCs, an approach that should be applicable to other cancers.
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21
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Okada Y, Shimane K, Kochi Y, Tahira T, Suzuki A, Higasa K, Takahashi A, Horita T, Atsumi T, Ishii T, Okamoto A, Fujio K, Hirakata M, Amano H, Kondo Y, Ito S, Takada K, Mimori A, Saito K, Kamachi M, Kawaguchi Y, Ikari K, Mohammed OW, Matsuda K, Terao C, Ohmura K, Myouzen K, Hosono N, Tsunoda T, Nishimoto N, Mimori T, Matsuda F, Tanaka Y, Sumida T, Yamanaka H, Takasaki Y, Koike T, Horiuchi T, Hayashi K, Kubo M, Kamatani N, Yamada R, Nakamura Y, Yamamoto K. A genome-wide association study identified AFF1 as a susceptibility locus for systemic lupus eyrthematosus in Japanese. PLoS Genet 2012; 8:e1002455. [PMID: 22291604 PMCID: PMC3266877 DOI: 10.1371/journal.pgen.1002455] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2011] [Accepted: 11/18/2011] [Indexed: 11/18/2022] Open
Abstract
Systemic lupus erythematosus (SLE) is an autoimmune disease that causes multiple organ damage. Although recent genome-wide association studies (GWAS) have contributed to discovery of SLE susceptibility genes, few studies has been performed in Asian populations. Here, we report a GWAS for SLE examining 891 SLE cases and 3,384 controls and multi-stage replication studies examining 1,387 SLE cases and 28,564 controls in Japanese subjects. Considering that expression quantitative trait loci (eQTLs) have been implicated in genetic risks for autoimmune diseases, we integrated an eQTL study into the results of the GWAS. We observed enrichments of cis-eQTL positive loci among the known SLE susceptibility loci (30.8%) compared to the genome-wide SNPs (6.9%). In addition, we identified a novel association of a variant in the AF4/FMR2 family, member 1 (AFF1) gene at 4q21 with SLE susceptibility (rs340630; P = 8.3×10(-9), odds ratio = 1.21). The risk A allele of rs340630 demonstrated a cis-eQTL effect on the AFF1 transcript with enhanced expression levels (P<0.05). As AFF1 transcripts were prominently expressed in CD4(+) and CD19(+) peripheral blood lymphocytes, up-regulation of AFF1 may cause the abnormality in these lymphocytes, leading to disease onset.
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Affiliation(s)
- Yukinori Okada
- Laboratory for Autoimmune Diseases, Center for Genomic Medicine (CGM), RIKEN, Yokohama, Japan
- Department of Allergy and Rheumatology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
- Laboratory for Statistical Analysis, CGM, RIKEN, Yokohama, Japan
| | - Kenichi Shimane
- Laboratory for Autoimmune Diseases, Center for Genomic Medicine (CGM), RIKEN, Yokohama, Japan
- Department of Allergy and Rheumatology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Yuta Kochi
- Laboratory for Autoimmune Diseases, Center for Genomic Medicine (CGM), RIKEN, Yokohama, Japan
- Department of Allergy and Rheumatology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
- * E-mail:
| | - Tomoko Tahira
- Division of Genome Analysis, Research Center for Genetic Information, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Akari Suzuki
- Laboratory for Autoimmune Diseases, Center for Genomic Medicine (CGM), RIKEN, Yokohama, Japan
| | - Koichiro Higasa
- Laboratory for Statistical Analysis, CGM, RIKEN, Yokohama, Japan
| | | | - Tetsuya Horita
- Department of Medicine II, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Tatsuya Atsumi
- Department of Medicine II, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Tomonori Ishii
- Department of Hematology and Rheumatology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Akiko Okamoto
- Department of Allergy and Rheumatology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Keishi Fujio
- Department of Allergy and Rheumatology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
| | - Michito Hirakata
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
| | - Hirofumi Amano
- Department of Internal Medicine and Rheumatology, Juntendo University School of Medicine, Tokyo, Japan
| | - Yuya Kondo
- Division of Clinical Immunology, Doctoral Program in Clinical Sciences, Graduate School of Comprehensive Human Science, University of Tsukuba, Tsukuba, Japan
| | - Satoshi Ito
- Division of Clinical Immunology, Doctoral Program in Clinical Sciences, Graduate School of Comprehensive Human Science, University of Tsukuba, Tsukuba, Japan
| | - Kazuki Takada
- Departments of Medicine and Rheumatology, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan
| | - Akio Mimori
- Division of Rheumatic Diseases, National Center for Global Health and Medicine, Tokyo, Japan
| | - Kazuyoshi Saito
- First Department of Internal Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Makoto Kamachi
- Department of Immunology and Rheumatology, Unit of Translational Medicine, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan
| | - Yasushi Kawaguchi
- Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan
| | - Katsunori Ikari
- Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan
| | - Osman Wael Mohammed
- Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Koichi Matsuda
- Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Chikashi Terao
- Department of Rheumatology and Clinical immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Koichiro Ohmura
- Department of Rheumatology and Clinical immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Keiko Myouzen
- Laboratory for Autoimmune Diseases, Center for Genomic Medicine (CGM), RIKEN, Yokohama, Japan
| | - Naoya Hosono
- Laboratory for Genotyping Development, CGM, RIKEN, Yokohama, Japan
| | | | - Norihiro Nishimoto
- Laboratory of Immune Regulation, Wakayama Medical University, Wakayama, Japan
| | - Tsuneyo Mimori
- Department of Rheumatology and Clinical immunology, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Fumihiko Matsuda
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yoshiya Tanaka
- First Department of Internal Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan
| | - Takayuki Sumida
- Division of Clinical Immunology, Doctoral Program in Clinical Sciences, Graduate School of Comprehensive Human Science, University of Tsukuba, Tsukuba, Japan
| | - Hisashi Yamanaka
- Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan
| | - Yoshinari Takasaki
- Department of Internal Medicine and Rheumatology, Juntendo University School of Medicine, Tokyo, Japan
| | - Takao Koike
- Department of Medicine II, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Takahiko Horiuchi
- Department of Medicine and Biosystemic Science, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
| | - Kenshi Hayashi
- Division of Genome Analysis, Research Center for Genetic Information, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Michiaki Kubo
- Laboratory for Genotyping Development, CGM, RIKEN, Yokohama, Japan
| | - Naoyuki Kamatani
- Laboratory for Statistical Analysis, CGM, RIKEN, Yokohama, Japan
| | - Ryo Yamada
- Laboratory for Autoimmune Diseases, Center for Genomic Medicine (CGM), RIKEN, Yokohama, Japan
- Center for Genomic Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yusuke Nakamura
- Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, University of Tokyo, Tokyo, Japan
| | - Kazuhiko Yamamoto
- Laboratory for Autoimmune Diseases, Center for Genomic Medicine (CGM), RIKEN, Yokohama, Japan
- Department of Allergy and Rheumatology, Graduate School of Medicine, University of Tokyo, Tokyo, Japan
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Abstract
Cellular memory is provided by two counteracting groups of chromatin proteins termed Trithorax group (TrxG) and Polycomb group (PcG) proteins. TrxG proteins activate transcription and are perhaps best known because of the involvement of the TrxG protein MLL in leukaemia. However, in terms of molecular analysis, they have lived in the shadow of their more famous counterparts, the PcG proteins. Recent advances have improved our understanding of TrxG protein function and demonstrated that the heterogeneous group of TrxG proteins is of critical importance in the epigenetic regulation of the cell cycle, senescence, DNA damage and stem cell biology.
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Muntean AG, Hess JL. The pathogenesis of mixed-lineage leukemia. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2011; 7:283-301. [PMID: 22017583 DOI: 10.1146/annurev-pathol-011811-132434] [Citation(s) in RCA: 255] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Aggressive leukemias arise in both children and adults as a result of rearrangements to the mixed-lineage leukemia gene (MLL) located on chromosome 11q23. MLL encodes a large histone methyltransferase that directly binds DNA and positively regulates gene transcription, including homeobox (HOX) genes. MLL is involved in chromosomal translocations, partial tandem duplications, and amplifications, all of which result in hematopoietic malignancies due to sustained HOX expression and stalled differentiation. MLL lesions are associated with both acute myeloid leukemia and acute lymphoid leukemia and are usually associated with a relatively poor prognosis despite improved treatment options such as allogeneic hematopoietic stem cell transplantation, which underscores the need for new treatment regimens. Recent advances have begun to reveal the molecular mechanisms that drive MLL-associated leukemias, which, in turn, have provided opportunities for therapeutic development. Here, we discuss the etiology of MLL leukemias and potential directions for future therapy.
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Affiliation(s)
- Andrew G Muntean
- Department of Pathology, University of Michigan Medical School, Ann Arbor, Michigan 48109, USA.
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24
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Logan CA, Somero GN. Effects of thermal acclimation on transcriptional responses to acute heat stress in the eurythermal fish Gillichthys mirabilis (Cooper). Am J Physiol Regul Integr Comp Physiol 2011; 300:R1373-83. [DOI: 10.1152/ajpregu.00689.2010] [Citation(s) in RCA: 89] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The capacities of eurythermal ectotherms to withstand wide ranges of temperature are based, in part, on abilities to modulate gene expression as body temperature changes, notably genes encoding proteins of the cellular stress response. Here, using a complementary DNA microarray, we investigated the sequence in which cellular stress response-linked genes are expressed during acute heat stress, to elucidate how severity of stress affects the categories of genes changing expression. We also studied how prior acclimation history affected gene expression in response to acute heat stress. Eurythermal goby fish ( Gillichthys mirabilis ) were acclimated to 9 ± 0.5, 19 ± 0.5, and 28 ± 0.5°C for 1 mo. Then fish were given an acute heat ramp (4°C/h), and gill tissues were sampled every +4°C to monitor gene expression. The average onset temperature for a significant change in expression during acute stress increased by ∼2°C for each ∼10°C increase in acclimation temperature. For some genes, warm acclimation appeared to obviate the need for expression change until the most extreme temperatures were reached. Sequential expression of different categories of genes reflected severity of stress. Regardless of acclimation temperature, the gene encoding heat shock protein 70 ( HSP70) was upregulated strongly during mild stress; the gene encoding the proteolytic protein ubiquitin ( UBIQ) was upregulated at slightly higher temperatures; and a gene encoding a protein involved in cell cycle arrest and apoptosis, cyclin-dependent kinase inhibitor 1B ( CDKN1B), was upregulated only under extreme stress. The tiered, stress level-related expression patterns and the effects of acclimation on induction temperature yield new insights into the fundamental mechanisms of eurythermy.
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Affiliation(s)
- Cheryl A. Logan
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, California
| | - George N. Somero
- Hopkins Marine Station, Department of Biology, Stanford University, Pacific Grove, California
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The heterodimerization domains of MLL—FYRN and FYRC—are potential target structures in t(4;11) leukemia. Leukemia 2011; 25:663-70. [DOI: 10.1038/leu.2010.308] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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27
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Waterworth DM, Ricketts SL, Song K, Chen L, Zhao JH, Ripatti S, Aulchenko YS, Zhang W, Yuan X, Lim N, Luan J, Ashford S, Wheeler E, Young EH, Hadley D, Thompson JR, Braund PS, Johnson T, Struchalin M, Surakka I, Luben R, Khaw KT, Rodwell SA, Loos RJF, Boekholdt SM, Inouye M, Deloukas P, Elliott P, Schlessinger D, Sanna S, Scuteri A, Jackson A, Mohlke KL, Tuomilehto J, Roberts R, Stewart A, Kesäniemi YA, Mahley RW, Grundy SM, McArdle W, Cardon L, Waeber G, Vollenweider P, Chambers JC, Boehnke M, Abecasis GR, Salomaa V, Järvelin MR, Ruokonen A, Barroso I, Epstein SE, Hakonarson HH, Rader DJ, Reilly MP, Witteman JCM, Hall AS, Samani NJ, Strachan DP, Barter P, van Duijn CM, Kooner JS, Peltonen L, Wareham NJ, McPherson R, Mooser V, Sandhu MS. Genetic variants influencing circulating lipid levels and risk of coronary artery disease. Arterioscler Thromb Vasc Biol 2010; 30:2264-76. [PMID: 20864672 DOI: 10.1161/atvbaha.109.201020] [Citation(s) in RCA: 318] [Impact Index Per Article: 22.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
OBJECTIVE Genetic studies might provide new insights into the biological mechanisms underlying lipid metabolism and risk of CAD. We therefore conducted a genome-wide association study to identify novel genetic determinants of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides. METHODS AND RESULTS We combined genome-wide association data from 8 studies, comprising up to 17 723 participants with information on circulating lipid concentrations. We did independent replication studies in up to 37 774 participants from 8 populations and also in a population of Indian Asian descent. We also assessed the association between single-nucleotide polymorphisms (SNPs) at lipid loci and risk of CAD in up to 9 633 cases and 38 684 controls. We identified 4 novel genetic loci that showed reproducible associations with lipids (probability values, 1.6×10(-8) to 3.1×10(-10)). These include a potentially functional SNP in the SLC39A8 gene for HDL-C, an SNP near the MYLIP/GMPR and PPP1R3B genes for LDL-C, and at the AFF1 gene for triglycerides. SNPs showing strong statistical association with 1 or more lipid traits at the CELSR2, APOB, APOE-C1-C4-C2 cluster, LPL, ZNF259-APOA5-A4-C3-A1 cluster and TRIB1 loci were also associated with CAD risk (probability values, 1.1×10(-3) to 1.2×10(-9)). CONCLUSIONS We have identified 4 novel loci associated with circulating lipids. We also show that in addition to those that are largely associated with LDL-C, genetic loci mainly associated with circulating triglycerides and HDL-C are also associated with risk of CAD. These findings potentially provide new insights into the biological mechanisms underlying lipid metabolism and CAD risk.
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Huo H, Magro PG, Pietsch EC, Patel BB, Scotto KW. Histone methyltransferase MLL1 regulates MDR1 transcription and chemoresistance. Cancer Res 2010; 70:8726-35. [PMID: 20861184 DOI: 10.1158/0008-5472.can-10-0755] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
The multidrug resistance 1 gene (MDR1) encodes P-glycoprotein (Pgp), a member of the ATP-binding cassette (ABC) transporter family that confers tumor drug resistance by actively effluxing a number of antitumor agents. We had previously shown that MDR1 transcription is regulated by epigenetic events such as histone acetylation, and had identified the histone acetylase P/CAF and the transcription factor NF-Y as the factors mediating the enzymatic and DNA-anchoring functions, respectively, at the MDR1 promoter. It has also been shown that MDR1 activation is accompanied by increased methylation on lysine 4 of histone H3 (H3K4). In this study, we further investigated histone methylation in MDR1 regulation and function. We show that the mixed lineage leukemia 1 (MLL1) protein, a histone methyltransferase specific for H3K4, is required for MDR1 promoter methylation, as knockdown of MLL1 resulted in a decrease in MDR1 expression. The regulation of MDR1 by MLL1 has functional consequences in that downregulation of MLL1 led to increased retention of the Pgp-specific substrate DIOC(2)(3), as well as increased cellular sensitivity to several Pgp substrates. Regulation of MDR1 by MLL1 was dependent on the CCAAT box within the proximal MDR1 promoter, similar to what we had shown for MDR1 promoter acetylation, and also requires NF-Y. Finally, overexpression of the most prevalent MLL fusion protein, MLL-AF4, led to increased MDR1 expression. This is the first identification of a histone methyltransferase and its leukemogenic rearrangement that regulates expression of an ABC drug transporter, suggesting a new target for circumvention of tumor multidrug resistance.
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Affiliation(s)
- Hairong Huo
- Department of Pharmacology, The Cancer Institute of New Jersey, Robert Wood Johnson Medical School, The University of Medicine and Dentistry of New Jersey, New Brunswick, New Jersey 08901, USA
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Park S, Osmers U, Raman G, Schwantes RH, Diaz MO, Bushweller JH. The PHD3 domain of MLL acts as a CYP33-regulated switch between MLL-mediated activation and repression . Biochemistry 2010; 49:6576-86. [PMID: 20677832 PMCID: PMC2916634 DOI: 10.1021/bi1009387] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
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The mixed lineage leukemia (MLL) gene plays a critical role in epigenetic regulation of gene expression and is a frequent target of chromosomal translocations leading to leukemia. MLL plant homeodomain 3 (PHD3) is lost in all MLL translocation products, and reinsertion of PHD3 into MLL fusion proteins abrogates their transforming activity. PHD3 has been shown to interact with the RNA-recognition motif (RRM) domain of human nuclear Cyclophilin33 (CYP33). Here, we show that CYP33 mediates downregulation of the expression of MLL target genes HOXC8, HOXA9, CDKN1B, and C-MYC, in a proline isomerase-dependent manner. This downregulation correlates with the reduction of trimethylated lysine 4 of histone H3 (H3K4me3) and histone H3 acetylation. We have structurally characterized both the PHD3 and CYP33 RRM domains and analyzed their binding to one another. The PHD3 domain binds H3K4me3 (preferentially) and the CYP33 RRM domain at distinct sites. Our binding data show that binding of H3K4me3 to PHD3 and binding of the CYP33 RRM domain to PHD3 are mutually inhibitory, implying that PHD3 is a molecular switch for the transition between activation and repression of target genes. To explore the possible mechanism of CYP33/PHD3-mediated repression, we have analyzed the CYP33 proline isomerase activity on various H3 and H4 peptides and shown selectivity for two sites in H3. Our results provide a possible mechanism for the MLL PHD3 domain to act as a switch between activation and repression.
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Affiliation(s)
- Sangho Park
- Department of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22908, USA
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30
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Phosphorylation of MLL by ATR is required for execution of mammalian S-phase checkpoint. Nature 2010; 467:343-6. [PMID: 20818375 PMCID: PMC2940944 DOI: 10.1038/nature09350] [Citation(s) in RCA: 108] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2009] [Accepted: 07/15/2010] [Indexed: 12/22/2022]
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31
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Liu H, Cheng EHY, Hsieh JJD. MLL fusions: pathways to leukemia. Cancer Biol Ther 2010; 8:1204-11. [PMID: 19729989 DOI: 10.4161/cbt.8.13.8924] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Human leukemias with chromosomal band 11q23 aberrations that disrupt the MLL/HRX/ALL-1 gene portend poor prognosis. MLL associated leukemias account for the majority of infant leukemia, approximately 10% of adult de novo leukemia and approximately 33% of therapy related acute leukemia with a balanced chromosome translocation. The 500 kD MLL precursor is processed by Taspase1 to generate mature MLL(N320/C180), which orchestrates many aspects of biology such as embryogenesis, cell cycle, cell fate and stem cell maintenance. Leukemogenic MLL translocations fuse the common MLL N-terminus (approximately 1,400 aa) in frame with more than 60 translocation partner genes (TPGs). Recent studies on MLL and MLL leukemia have greatly advanced our knowledge concerning the normal function of MLL and its deregulation in leukemogenesis. Here, we summarize the critical biological and pathological activities of MLL and MLL fusions, and discuss available models and potential therapeutic targets of MLL associated leukemias.
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Affiliation(s)
- Han Liu
- Molecular Oncology, Department of Medicine, Siteman Cancer Center, Washington University School of Medicine, St. Louis, MO 63110, USA
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32
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Kotani A, Ha D, Schotte D, den Boer ML, Armstrong SA, Lodish HF. A novel mutation in the miR-128b gene reduces miRNA processing and leads to glucocorticoid resistance of MLL-AF4 acute lymphocytic leukemia cells. Cell Cycle 2010; 9:1037-42. [PMID: 20237425 DOI: 10.4161/cc.9.6.11011] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
MLL-AF4 acute lymphocytic leukemia has a poor prognosis, and the mechanisms by which these leukemias develop are not understood despite intensive research based on well-known concepts and methods. MicroRNAs (miRNAs) are a new class of small noncoding RNAs that post-transcriptionally regulate expression of target mRNA transcripts. We recently reported that ectopic expression of miR-128b together with miR-221, two of the miRNAs downregulated in MLL-AF4 ALL, restores glucocorticoid resistance through downregulation of the MLL-AF4 chimeric fusion proteins MLL-AF4 and AF4-MLL that are generated by chromosomal translocation t(4;11). Here we report the identification of new mutations in miR-128b in RS4;11 cells, derived from MLL-AF4 ALL patient. One novel mutation significantly reduces the processing of miR-128b. Finally, this base change occurs in a primary MLL-AF4 ALL sample as an acquired mutation. These results demonstrate that the novel mutation in miR-128b in MLL-AF4 ALL alters the processing of miR-128b and that the resultant downregulation of mature miR-128b contributes to glucocorticoid resistance through the failure to downregulate the fusion oncogenes.
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Affiliation(s)
- Ai Kotani
- Division of Molecular Therapy Advanced Clinical Research Center, Institute of Medical Science, The University of Tokyo, Tokyo, Japan
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33
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Daniel-Cravioto A, Gonzalez-Bonilla CR, Mejia-Arangure JM, Perez-Saldivar ML, Fajardo-Gutierrez A, Jimenez-Hernandez E, Hernandez-Serrano M, Bekker-Mendez VC. Genetic rearrangement MLL/AF4 is most frequent in children with acute lymphoblastic leukemias in Mexico City. Leuk Lymphoma 2010; 50:1352-60. [PMID: 19579075 DOI: 10.1080/10428190903015636] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
One of the highest incidences of acute lymphoblastic leukemia (ALL) in the world has been reported in Mexico City. In the current study (26 cases), the frequencies of the most frequent genetic rearrangements TEL-AML1, MLL/AF4, BCR-ABL (major and minor) in ALL in children from Mexico City were determined. For the ALL, the frequency of MLL/AF4 was 65.4%, for TEL-AML1 and that of BCR/ABL was 3.8%. Only 6 of the 17 children with the MLL/AF4 rearrangement were less than 26 months old. The frequency reported for MLL/AF4 in Mexican children with ALL is one of the highest worldwide. These findings could potentially explain the higher frequency of ALL with poor prognosis for children in Mexico City.
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Affiliation(s)
- Alondra Daniel-Cravioto
- Unidad de Investigación Biomédica en Infectología e Inmunología, Unidad Medica de Alta Especialidad (UMAE), Hospital de Infectología Daniel Mendez Hernandez del Centro Medico Nacional La Raza, Instituto Mexicano del Seguro Social (IMSS), Mexico City, Mexico
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miR-128b is a potent glucocorticoid sensitizer in MLL-AF4 acute lymphocytic leukemia cells and exerts cooperative effects with miR-221. Blood 2009; 114:4169-78. [PMID: 19749093 DOI: 10.1182/blood-2008-12-191619] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
MLL-AF4 acute lymphocytic leukemia (ALL) has a poor prognosis. MicroRNAs (miRNA) are small noncoding RNAs that posttranscriptionally regulate expression of target mRNAs. Our analysis of previously published data showed that expression of miR-128b and miR-221 is down-regulated in MLL-rearranged ALL relative to other types of ALL. Reexpression of these miRNAs cooperatively sensitizes 2 cultured lines of MLL-AF4 ALL cells to glucocorticoids. Target genes down-regulated by miR-128b include MLL, AF4, and both MLL-AF4 and AF4-MLL fusion genes; miR-221 down-regulates CDKN1B. These results demonstrate that down-regulation of miR-128b and miR-221 is implicated in glucocorticoid resistance and that restoration of their levels is a potentially promising therapeutic in MLL-AF4 ALL.
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35
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Molecular targeting of MLL-rearranged leukemia cell lines with the synthetic peptide PFWT synergistically enhances the cytotoxic effect of established chemotherapeutic agents. Leuk Res 2009; 33:937-47. [PMID: 19232721 DOI: 10.1016/j.leukres.2009.01.018] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2008] [Revised: 01/12/2009] [Accepted: 01/15/2009] [Indexed: 11/21/2022]
Abstract
MLL leukemias are characterized cytogenetically by reciprocal translocations of the MLL gene at 11q23 and clinically by unfavorable outcomes. Evidence indicating that MLL leukemias are resistant to apoptosis encourages the identification of agents that induce cell death by other mechanisms. The AF4-mimetic peptide PFWT induces necrosis in the t(4;11) leukemia cell line, MV4-11. Treatment of MV4-11 cells with PFWT in combination with four chemotherapeutic compounds results in sequence-dependent synergy, induction of both apoptotic and necrotic cell death, and inhibition of MV4-11 clonogenicity. Therefore, PFWT holds promise as a therapy for MLL leukemias that augments the effects of several clinically available chemotherapeutic agents.
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36
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Glycogen synthase kinase 3 in MLL leukaemia maintenance and targeted therapy. Nature 2008; 455:1205-9. [PMID: 18806775 DOI: 10.1038/nature07284] [Citation(s) in RCA: 227] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2008] [Accepted: 07/18/2008] [Indexed: 12/20/2022]
Abstract
Glycogen synthase kinase 3 (GSK3) is a multifunctional serine/threonine kinase that participates in numerous signalling pathways involved in diverse physiological processes. Several of these pathways are implicated in disease pathogenesis, which has prompted efforts to develop GSK3-specific inhibitors for therapeutic applications. However, before now, there has been no strong rationale for targeting GSK3 in malignancies. Here we report pharmacological, physiological and genetic studies that demonstrate an oncogenic requirement for GSK3 in the maintenance of a specific subtype of poor prognosis human leukaemia, genetically defined by mutations of the MLL proto-oncogene. In contrast to its previously characterized roles in suppression of neoplasia-associated signalling pathways, GSK3 paradoxically supports MLL leukaemia cell proliferation and transformation by a mechanism that ultimately involves destabilization of the cyclin-dependent kinase inhibitor p27(Kip1). Inhibition of GSK3 in a preclinical murine model of MLL leukaemia provides promising evidence of efficacy and earmarks GSK3 as a candidate cancer drug target.
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37
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Kennedy JA, Barabé F. Investigating human leukemogenesis: from cell lines to in vivo models of human leukemia. Leukemia 2008; 22:2029-40. [DOI: 10.1038/leu.2008.206] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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38
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MLL protects CpG clusters from methylation within the Hoxa9 gene, maintaining transcript expression. Proc Natl Acad Sci U S A 2008; 105:7517-22. [PMID: 18483194 DOI: 10.1073/pnas.0800090105] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Homeobox (HOX) genes play a definitive role in determination of cell fate during embryogenesis and hematopoiesis. MLL-related leukemia is coincident with increased expression of a subset of HOX genes, including HOXA9. MLL functions to maintain, rather than initiate, expression of its target genes. However, the mechanism of MLL maintenance of target gene expression is not understood. Here, we demonstrate that Mll binds to specific clusters of CpG residues within the Hoxa9 locus and regulates expression of multiple transcripts. The presence of Mll at these clusters provides protection from DNA methylation. shRNA knock-down of Mll reverses the methylation protection status at the previously protected CpG clusters; methylation at these CpG residues is similar to that observed in Mll null cells. Furthermore, reconstituting MLL expression in Mll null cells can reverse DNA methylation of the same CpG residues, demonstrating a dominant effect of MLL in protecting this specific region from DNA methylation. Intriguingly, an oncogenic MLL-AF4 fusion can also reverse DNA methylation, but only for a subset of these CpGs. This method of transcriptional regulation suggests a mechanism that explains the role of Mll in transcriptional maintenance, but it may extend to other CpG DNA binding proteins. Protection from methylation may be an important mechanism of epigenetic inheritance by regulating the function of both de novo and maintenance DNA methyltransferases.
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39
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Jude CD, Climer L, Xu D, Artinger E, Fisher JK, Ernst P. Unique and independent roles for MLL in adult hematopoietic stem cells and progenitors. Cell Stem Cell 2008; 1:324-37. [PMID: 18371366 DOI: 10.1016/j.stem.2007.05.019] [Citation(s) in RCA: 235] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2007] [Revised: 04/15/2007] [Accepted: 05/22/2007] [Indexed: 12/17/2022]
Abstract
The Mixed Lineage Leukemia (MLL) gene is essential for embryonic hematopoietic stem cell (HSC) development, but its role during adult hematopoiesis is unknown. Using an inducible knockout model, we demonstrate that Mll is essential for the maintenance of adult HSCs and progenitors, with fatal bone marrow failure occurring within 3 weeks of Mll deletion. Mll-deficient cells are selectively lost from mixed bone marrow chimeras, demonstrating their failure to self-renew even in an intact bone marrow environment. Surprisingly, HSCs lacking Mll exhibit ectopic cell-cycle entry, resulting in the depletion of quiescent HSCs. In contrast, Mll deletion in myelo-erythroid progenitors results in reduced proliferation and reduced response to cytokine-induced cell-cycle entry. Committed lymphoid and myeloid cells no longer require Mll, defining the early multipotent stages of hematopoiesis as Mll dependent. These studies demonstrate that Mll plays selective and independent roles within the hematopoietic system, maintaining quiescence in HSCs and promoting proliferation in progenitors.
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Affiliation(s)
- Craig D Jude
- Department of Genetics and Norris Cotton Cancer Center, Dartmouth Medical School, 725 Remsen, HB7400, Hanover, NH 03755, USA
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40
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Mechanisms of transcriptional regulation by MLL and its disruption in acute leukemia. Int J Hematol 2007; 87:10-8. [DOI: 10.1007/s12185-007-0009-8] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Accepted: 07/20/2007] [Indexed: 10/22/2022]
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41
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Liu H, Cheng EHY, Hsieh JJD. Bimodal degradation of MLL by SCFSkp2 and APCCdc20 assures cell cycle execution: a critical regulatory circuit lost in leukemogenic MLL fusions. Genes Dev 2007; 21:2385-98. [PMID: 17908926 PMCID: PMC1993870 DOI: 10.1101/gad.1574507] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Human chromosome 11q23 translocations disrupting MLL result in poor prognostic leukemias. It fuses the common MLL N-terminal approximately 1400 amino acids in-frame with >60 different partners without shared characteristics. In addition to the well-characterized activity of MLL in maintaining Hox gene expression, our recent studies established an MLL-E2F axis in orchestrating core cell cycle gene expression including Cyclins. Here, we demonstrate a biphasic expression of MLL conferred by defined windows of degradation mediated by specialized cell cycle E3 ligases. Specifically, SCF(Skp2) and APC(Cdc20) mark MLL for degradation at S phase and late M phase, respectively. Abolished peak expression of MLL incurs corresponding defects in G1/S transition and M-phase progression. Conversely, overexpression of MLL blocks S-phase progression. Remarkably, MLL degradation initiates at its N-terminal approximately 1400 amino acids, and tested prevalent MLL fusions are resistant to degradation. Thus, impaired degradation of MLL fusions likely constitutes the universal mechanism underlying all MLL leukemias. Our data conclude an essential post-translational regulation of MLL by the cell cycle ubiquitin/proteasome system (UPS) assures the temporal necessity of MLL in coordinating cell cycle progression.
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Affiliation(s)
- Han Liu
- Molecular Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
- Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - Emily H.-Y. Cheng
- Molecular Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
- Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri 63110, USA
- Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
| | - James J.-D. Hsieh
- Molecular Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
- Siteman Cancer Center, Washington University School of Medicine, St. Louis, Missouri 63110, USA
- Department of Molecular Biology and Pharmacology, Washington University School of Medicine, St. Louis, Missouri 63110, USA
- Corresponding author.E-MAIL ; FAX (314) 362-1589
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42
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Kowarz E, Burmeister T, Lo Nigro L, Jansen MWJC, Delabesse E, Klingebiel T, Dingermann T, Meyer C, Marschalek R. Complex MLL rearrangements in t(4;11) leukemia patients with absent AF4 · MLL fusion allele. Leukemia 2007; 21:1232-8. [PMID: 17410185 DOI: 10.1038/sj.leu.2404686] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The human mixed lineage leukemia (MLL) gene is frequently involved in genetic rearrangements with more than 55 different translocation partner genes, all associated with acute leukemia. Reciprocal chromosomal translocations generate two MLL fusion alleles, where 5'- and 3'-portions of MLL are fused to gene segments of given fusion partners. In case of t(4;11) patients, about 80% of all patients exhibit both reciprocal fusion alleles, MLL.AF4 and AF4.MLL, respectively. By contrast, 20% of all t(4;11) patients seem to encode only the MLL.AF4 fusion allele. Here, we analyzed these 'MLL.AF4(+)/AF4.MLL(-)' patients at the genomic DNA level to unravel their genetic situation. Cryptic translocations and three-way translocations were found in this group of t(4;11) patients. Reciprocal MLL fusions with novel translocation partner genes, for example NF-KB1 and RABGAP1L, were identified and actively transcribed in leukemic cells. In other patients, the reciprocal 3'-MLL gene segment was fused out-of-frame to PBX1, ELF2, DSCAML1 and FXYD6. The latter rearrangements caused haploinsufficiency of genes that are normally expressed in hematopoietic cells. Finally, patients were identified that encode only solitary 3'-MLL gene segments on the reciprocal allele. Based on these data, we propose that all t(4;11) patients exhibit reciprocal MLL alleles, but due to the individual recombination events, provide different pathological disease mechanisms.
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Affiliation(s)
- E Kowarz
- Institute of Pharmaceutical Biology, ZAFES, DCAL, JWG-University Frankfurt, Biocenter, Frankfurt, Main, Germany
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43
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Santillan DA, Theisler CM, Ryan AS, Popovic R, Stuart T, Zhou MM, Alkan S, Zeleznik-Le NJ. Bromodomain and histone acetyltransferase domain specificities control mixed lineage leukemia phenotype. Cancer Res 2006; 66:10032-9. [PMID: 17047066 DOI: 10.1158/0008-5472.can-06-2597] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A critical unanswered question about mixed lineage leukemia (MLL) is how specific MLL fusion partners control leukemia phenotype. The MLL-cyclic AMP-responsive element binding protein-binding protein (CBP) fusion requires both the CBP bromodomain and histone acetyltransferase (HAT) domain for transformation and causes acute myelogenous leukemia (AML), often preceded by a myelodysplastic phase. We did domain-swapping experiments to define whether unique specificities of these CBP domains drive this specific MLL phenotype. Within MLL-CBP, we replaced the CBP bromodomain or HAT domain with P300/CBP-associated factor (P/CAF) or TAF(II)250 bromodomains or the P/CAF or GCN5 HAT domains. HAT, but not bromodomain, substitutions conferred enhanced proliferative capacity in vitro but lacked expression of myeloid cell surface markers normally seen with MLL-CBP. Mice reconstituted with domain-swapped hematopoietic progenitors developed different disease from those with MLL-CBP. This included development of lymphoid disease and lower frequency of the myelodysplastic phase in those mice developing AML. We conclude that both the CBP bromodomain and HAT domain play different but critical roles in determining the phenotype of MLL-CBP leukemia. Our results support an important role for MLL partner genes in determining the leukemia phenotype besides their necessity in leukemogenesis. Here, we find that subtleties in MLL fusion protein domain specificity direct cells toward a specific disease phenotype.
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Affiliation(s)
- Donna A Santillan
- Molecular Biology Program, Loyola University Medical Center, Maywood, Illinois 60153, USA
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44
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Gaussmann A, Wenger T, Eberle I, Bursen A, Bracharz S, Herr I, Dingermann T, Marschalek R. Combined effects of the two reciprocal t(4;11) fusion proteins MLL.AF4 and AF4.MLL confer resistance to apoptosis, cell cycling capacity and growth transformation. Oncogene 2006; 26:3352-63. [PMID: 17130830 DOI: 10.1038/sj.onc.1210125] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The reciprocal chromosomal translocation t(4;11) is correlated with infant, childhood, adult and therapy-related high-risk acute leukemia. Here, we investigated the biological effects of MLL.AF4, AF4.MLL or the combination of both reciprocal fusion proteins in a conditional in vitro cell culture model system. Several parameters like cell growth, cell cycling capacity, apoptotic behavior and growth transformation were investigated under physiological and stress conditions. Co-transfected cells displayed the highest resistance against apoptotic triggers, cell cycling capacity and loss-of-contact inhibition. These analyses were complemented by gene expression profiling experiments and specific gene signatures were established for each of the three cell lines. Interestingly, co-transfected cells strongly upregulate the homeobox gene Nanog. In combination with Oct4, the Nanog homeoprotein is steering maintenance of pluripotency and self-renewal in embryonic stem cells. Transcription of Nanog and other stem cell factors, like Oct4 and Bmi1, was verified in biopsy material of t(4;11) patient cells which express both reciprocal t(4;11) fusion genes. In conclusion, the presence of both reciprocal MLL fusion proteins confers biological properties known from t(4;11) leukemia, suggesting that each of the two fusion proteins contribute specific properties and, in combination, also synergistic effects to the leukemic phenotype.
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Affiliation(s)
- A Gaussmann
- Institute of Pharmaceutical Biology/ZAFES, JWG-University Frankfurt, Biocenter, Frankfurt/Main, Germany
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45
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Basecke J, Whelan JT, Griesinger F, Bertrand FE. The MLL partial tandem duplication in acute myeloid leukaemia. Br J Haematol 2006; 135:438-49. [PMID: 16965385 DOI: 10.1111/j.1365-2141.2006.06301.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Mixed lineage leukaemia gene-partial tandem duplications (MLL-PTD) characterise acute myeloid leukaemia (AML) with trisomy 11 and AML with a normal karyotype. MLL-PTD confer a worse prognosis with shortened overall and event free survival in childhood and adult AML. In spite of these clinical observations, the leukaemogenic mechanism has, so far, not been determined. This review summarises clinical studies on MLL-PTD positive AML and recent experimental findings on the putative leukaemogenic role of MLL-PTD.
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Affiliation(s)
- Jorg Basecke
- Division of Haematology and Oncology, University of Goettingen, Goettingen, Germany.
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46
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Takeda S, Chen DY, Westergard TD, Fisher JK, Rubens JA, Sasagawa S, Kan JT, Korsmeyer SJ, Cheng EHY, Hsieh JJD. Proteolysis of MLL family proteins is essential for taspase1-orchestrated cell cycle progression. Genes Dev 2006; 20:2397-409. [PMID: 16951254 PMCID: PMC1560414 DOI: 10.1101/gad.1449406] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Taspase1 was identified as the threonine endopeptidase that cleaves mixed-lineage leukemia (MLL) for proper Hox gene expression in vitro. To investigate its functions in vivo, we generated Taspase1(-/-) mice. Taspase1 deficiency results in noncleavage (nc) of MLL and MLL2 and homeotic transformations. Remarkably, our in vivo studies uncover an unexpected role of Taspase1 in the cell cycle. Taspase1(-/-) animals are smaller in size. Taspase1(-/-) mouse embryonic fibroblasts (MEFs) exhibit impaired proliferation, and acute deletion of Taspase1 leads to a marked reduction of thymocytes. Taspase1 deficiency incurs down-regulation of Cyclin Es, As, and Bs and up-regulation of p16(Ink4a) . We show that MLL and MLL2 directly target E2Fs for Cyclin expression. The uncleaved precursor MLL displays a reduced histone H3 methyl transferase activity in vitro. Accordingly, chromatin immunoprecipitation assays demonstrate a markedly decreased histone H3 K4 trimethylation at Cyclin E1 and E2 genes in Taspase1(-/-) cells. Furthermore, MLL(nc/nc;2nc/nc) MEFs are also impaired in proliferation. Our data are consistent with a model in which precursor MLLs, activated by Taspase1, target to Cyclins through E2Fs to methylate histone H3 at K4, leading to activation. Lastly, Taspase1(-/-) cells are resistant to oncogenic transformation, and Taspase1 is overexpressed in many cancer cell lines. Thus, Taspase1 may serve as a target for cancer therapeutics.
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Affiliation(s)
- Shugaku Takeda
- Molecular Oncology, Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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Hayne CC, Winer E, Williams T, Chaves F, Khorsand J, Mark HFL. Acute lymphoblastic leukemia with 4;11 translocation analyzed by a multi-modal strategy of conventional cytogenetics, FISH, morphology, flow cytometry and molecular genetics, and review of the literature. Exp Mol Pathol 2006; 81:62-71. [PMID: 16765346 DOI: 10.1016/j.yexmp.2006.04.002] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2006] [Revised: 04/09/2006] [Accepted: 04/17/2006] [Indexed: 11/23/2022]
Abstract
We report a case of acute lymphoblastic leukemia (ALL) with a 4;11 translocation. Metaphase cells and interphase nuclei derived from a routine unstimulated culture of bone marrow were analyzed using a combined strategy of G-banding and fluorescent in situ hybridization (FISH) in addition to hematopathological analysis, flow cytometry, and molecular genetics. This multimodal approach enables a successful correlation of pathology and cytogenetics to support a comprehensive diagnosis of the patient. Meaningful prognostication and appropriate therapeutic considerations are possible only when accurate diagnostic information is given. We further search and review the literature for the most up-to-date information currently available for this subtype of ALL in the constantly evolving field of molecular cytogenetics.
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Affiliation(s)
- Cynthia C Hayne
- Boston University School of Medicine, 700 Albany Street, Suite 408, Boston, MA 02118, USA
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48
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Chen W, Li Q, Hudson WA, Kumar A, Kirchhof N, Kersey JH. A murine Mll-AF4 knock-in model results in lymphoid and myeloid deregulation and hematologic malignancy. Blood 2006; 108:669-77. [PMID: 16551973 PMCID: PMC1895483 DOI: 10.1182/blood-2005-08-3498] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The 2 most frequent human MLL hematopoietic malignancies involve either AF4 or AF9 as fusion partners; each has distinct biology but the role of the fusion partner is not clear. We produced Mll-AF4 knock-in (KI) mice by homologous recombination in embryonic stem cells and compared them with Mll-AF9 KI mice. Young Mll-AF4 mice had lymphoid and myeloid deregulation manifest by increased lymphoid and myeloid cells in hematopoietic organs. In vitro, bone marrow cells from young mice formed unique mixed pro-B lymphoid (B220(+)CD19(+)CD43(+)sIgM(-), PAX5(+), TdT(+), IgH rearranged)/myeloid (CD11b/Mac1(+), c-fms(+), lysozyme(+)) colonies when grown in IL-7- and Flt3 ligand-containing media. Mixed lymphoid/myeloid hyperplasia and hematologic malignancies (most frequently B-cell lymphomas) developed in Mll-AF4 mice after prolonged latency; long latency to malignancy indicates that Mll-AF4-induced lymphoid/myeloid deregulation alone is insufficient to produce malignancy. In contrast, young Mll-AF9 mice had predominately myeloid deregulation in vivo and in vitro and developed myeloid malignancies. The early onset of distinct mixed lymphoid/myeloid lineage deregulation in Mll-AF4 mice shows evidence for both "instructive" and "noninstructive" roles for AF4 and AF9 as partners in MLL fusion genes. The molecular basis for "instruction" and secondary cooperating mutations can now be studied in our Mll-AF4 model.
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Affiliation(s)
- Weili Chen
- Cancer Center, University of Minnesota, Minneapolis, USA
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Eguchi M, Eguchi-Ishimae M, Knight D, Kearney L, Slany R, Greaves M. MLL chimeric protein activation renders cells vulnerable to chromosomal damage: An explanation for the very short latency of infant leukemia. Genes Chromosomes Cancer 2006; 45:754-60. [PMID: 16688745 DOI: 10.1002/gcc.20338] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
MLL fusion genes are a predominant feature of acute leukemias in infants and in secondary acute myeloid leukemia (AML) associated with prior chemotherapy with topo-II poisons. The former is considered to possibly arise in utero via transplacental chemical exposure. A striking feature of these leukemias is their malignancy and remarkably brief latencies implying the rapid acquisition of any necessary additional mutations. We have suggested that these coupled features might be explained if MLL fusion gene encoded proteins rendered cells more vulnerable to further DNA damage and mutation in the presence of chronic exposure to the agent(s) that induced the MLL fusion itself. We have tested this idea by exploiting a hormone regulated MLL-ENL (MLLT1) activation system and show that MLL-ENL function in normal murine progenitor cells substantially increases the incidence of chromosomal abnormalities in proliferating cells that survive exposure to etoposide VP-16. This phenotype is associated with an altered pattern of cell cycle arrest and/or apoptosis.
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Affiliation(s)
- Mariko Eguchi
- Section of Haemato-Oncology, The Institute of Cancer Research, London, UK
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