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Tang L, Peng L, Tan C, Liu H, Chen P, Wang H. Role of HOXA9 in solid tumors: mechanistic insights and therapeutic potential. Cancer Cell Int 2022; 22:349. [PMID: 36376832 PMCID: PMC9664671 DOI: 10.1186/s12935-022-02767-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Accepted: 10/19/2022] [Indexed: 11/16/2022] Open
Abstract
HOXA9 functioning as a transcription factor is one of the members of HOX gene family, which governs multiple cellular activities by facilitating cellular signal transduction. In addition to be a driver in AML which has been widely studied, the role of HOXA9 in solid tumor progression has also received increasing attention in recent years, where the aberrant expression of HOXA9 is closely associated with the prognosis of patient. This review details the signaling pathways, binding partners, post-transcriptional regulation of HOXA9, and possible inhibitors of HOXA9 in solid tumors, which provides a reference basis for further study on the role of HOXA9 in solid tumors.
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Kalmode H, Podsiadly I, Kabra A, Boulton A, Reddy P, Gao Y, Li C, Bushweller JH. Small-Molecule Inhibitors of the MLL1 CXXC Domain, an Epigenetic Reader of DNA Methylation. ACS Med Chem Lett 2022; 13:1363-1369. [PMID: 35978680 PMCID: PMC9377001 DOI: 10.1021/acsmedchemlett.2c00198] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The CXXC domain is a reader of DNA methylation which preferentially binds to unmethylated CpG DNA motifs. Chromosomal translocations involving the MLL1 gene produce in-frame fusion proteins in which the N-terminal portion of the MLL1 protein harboring its CXXC domain is fused to the C-terminal portion of multiple partners. For the MLL-AF9 fusion, mutations which disrupt CXXC domain-DNA binding abrogate the ability to cause leukemia in mice. Based on this, we initiated an effort to develop small-molecule inhibitors of the MLL1 CXXC domain as a novel approach to therapy. We developed a fluorescence polarization-based assay for MLL CXXC domain-DNA binding and screened a library of Cys-reactive molecules. For the most potent hit from this screen, we have synthesized a library of analogs to explore the structure-activity relationship, defined the binding site using chemical shift perturbations in NMR spectra, and explored the selectivity of compounds across the CXXC domain family.
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Affiliation(s)
- Hanuman
P. Kalmode
- Department
of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Izabella Podsiadly
- Department
of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Ashish Kabra
- Department
of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Adam Boulton
- Department
of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Prabhakar Reddy
- Department
of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Yan Gao
- Department
of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22903, United States
| | - Christopher Li
- Department
of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22903, United States
| | - John H. Bushweller
- Department
of Molecular Physiology and Biological Physics, University of Virginia, Charlottesville, Virginia 22903, United States
- Department
of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
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3
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ST8SIA6-AS1 Promotes the Epithelial-to-Mesenchymal Transition and Angiogenesis of Pituitary Adenoma. JOURNAL OF ONCOLOGY 2022; 2022:7960261. [PMID: 35783150 PMCID: PMC9242794 DOI: 10.1155/2022/7960261] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 02/09/2022] [Accepted: 03/11/2022] [Indexed: 11/17/2022]
Abstract
To investigate the effect of long noncoding RNA ST8SIA6-AS1 on the epithelial-to-mesenchymal transition (EMT) and angiogenesis of pituitary adenoma and its possible mechanism. The expression levels of ST8SIA6-AS1 and HOXA9 in noninvasive pituitary adenoma and invasive pituitary adenoma were detected using qRT-PCR. sh-ST8SIA6-AS1 transfection silenced the expression of ST8SIA6-AS1 in GH3 and GTI-1 cells. The effects of ST8SIA6-AS1 on the proliferation, invasion, angiogenesis, and EMT of GH3 and GTI-1 pituitary adenoma cells were detected. The migration ability of cells was detected through scratch assay. Dual luciferase analysis verified the targeting relationship between ST8SIA6-AS1 and miR-5195-3p. ST8SIA6-AS1 and HOXA9 were highly expressed in invasive pituitary adenoma. In pituitary adenomas, miR-5195-3p directly targeted HOXA9. miR-5195-3p is the target gene of ST8SIA6-AS1. ST8SIA6-AS1 knockdown inhibited the proliferation, invasion, angiogenesis, and EMT of pituitary adenoma. HOXA9 expression mediates the biological effect of ST8SIA6-AS1. ST8SIA6-AS1 targets miR-5195-3p to regulate the expression of HOXA9 and promote the EMT of pituitary adenomas.
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4
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Liang L, Ma K, Wang Z, Janissen R, Yu Z. Dynamics and inhibition of MLL1 CXXC domain on DNA revealed by single-molecule quantification. Biophys J 2021; 120:3283-3291. [PMID: 34280370 DOI: 10.1016/j.bpj.2021.03.045] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2020] [Revised: 02/09/2021] [Accepted: 03/11/2021] [Indexed: 02/05/2023] Open
Abstract
CpG islands recruit MLL1 via the CXXC domain to modulate chromatin structure and regulate gene expression. The amino acid motif of CXXC also plays a pivotal role in MLL1's structure and function and serves as a target for drug design. In addition, the CpG pattern in an island governs spatially dependent collaboration among CpGs in recruiting epigenetic enzymes. However, current studies using short DNA fragments cannot probe the dynamics of CXXC on long DNA with crowded CpG motifs. Here, we used single-molecule magnetic tweezers to examine the binding dynamics of MLL1's CXXC domain on a long DNA with a CpG island. The mechanical strand separation assay allows profiling of protein-DNA complexes and reports force-dependent unfolding times. Further design of a hairpin detector reveals the unfolding time of individual CXXC-CpG complexes. Finally, in a proof of concept we demonstrate the inhibiting effect of dimethyl fumarate on the CXXC-DNA complexes by measuring the dose response curve of the unfolding time. This demonstrates the potential feasibility of using single-molecule strand separation as a label-free detector in drug discovery and chemical biology.
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Affiliation(s)
- Lin Liang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Kangkang Ma
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Zeyu Wang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Richard Janissen
- Department of Bionanoscience, Kavli Institute of Nanoscience, Delft, South-Holland, The Netherlands
| | - Zhongbo Yu
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China.
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5
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Chen W, Chen X, Li D, Wang X, Long G, Jiang Z, You Q, Guo X. Discovery of a potent MLL1 and WDR5 protein-protein interaction inhibitor with in vivo antitumor activity. Eur J Med Chem 2021; 223:113677. [PMID: 34225179 DOI: 10.1016/j.ejmech.2021.113677] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/18/2021] [Accepted: 06/25/2021] [Indexed: 10/21/2022]
Abstract
MLL1-WDR5 interaction is essential for the formation of MLL core complex and its H3K4 methyltransferase activity. Disrupting MLL1-WDR5 interaction has been proposed as a potential therapeutic approach in the treatment of leukemia. A "toolkit" of well-characterized chemical probe will allow exploring animal studies. Based on a specific MLL1-WDR5 PPI inhibitor (DDO-2117), which was previously reported by our group, we conducted a bioisosterism approach by click chemistry to discover novel phenyltriazole scaffold MLL1-WDR5 interaction blockers. Here, our efforts resulted in the best inhibitor 24 (DDO-2093) with high binding affinity (Kd = 11.6 nM) and with improved drug-like properties. Both in vitro and in vivo assays revealed 24 could efficiently block the MLL1-WDR5 interaction. Furthermore, 24 significantly suppressed tumor growth in the MV4-11 xenograft mouse model and showed a favorable safety profile. We propose 24 as a chemical probe that is suitable for in vivo pharmacodynamic and biological studies of MLL1-WDR5 interaction.
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Affiliation(s)
- Weilin Chen
- Jiangsu Key Laboratory of Drug Design and Optimization and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, Nanjing Medical University, Nanjing, 211166, China
| | - Xin Chen
- Jiangsu Key Laboratory of Drug Design and Optimization and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
| | - Dongdong Li
- Jiangsu Key Laboratory of Drug Design and Optimization and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
| | - Xianghan Wang
- Jiangsu Key Laboratory of Drug Design and Optimization and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
| | - Guanlu Long
- Jiangsu Key Laboratory of Drug Design and Optimization and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China
| | - Zhengyu Jiang
- Jiangsu Key Laboratory of Drug Design and Optimization and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
| | - Qidong You
- Jiangsu Key Laboratory of Drug Design and Optimization and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
| | - Xiaoke Guo
- Jiangsu Key Laboratory of Drug Design and Optimization and State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 210009, China; Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
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6
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Zhai X, Brownell JE. Biochemical perspectives on targeting KMT2 methyltransferases in cancer. Trends Pharmacol Sci 2021; 42:688-699. [PMID: 34074527 DOI: 10.1016/j.tips.2021.05.002] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 04/20/2021] [Accepted: 05/05/2021] [Indexed: 02/05/2023]
Abstract
KMT2 methyltransferases are important regulators of gene transcription through the methylation of histone H3 lysine 4 at promoter and enhancer regions. They reside in large, multisubunit protein complexes, which not only regulate their catalytic activities but also mediate their interactions with chromatin. The KMT2 family was initially associated with cancer due to the discovery of KMT2A translocations in mixed-lineage leukemia (MLL). However, emerging evidences suggest that the methyltransferase activity of KMT2 enzymes can also be important in cancer, raising the prospect of targeting the catalytic domain of KMT2 as a therapeutic strategy. In this review, we summarize recent advances in our understanding of KMT2 enzyme mechanisms and their regulation on nucleosomes, which will provide mechanistic insights into therapeutic discoveries targeting their methyltransferase activities.
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Affiliation(s)
- Xiang Zhai
- Mechanistic Biology & Profiling, Discovery Sciences, R&D, AstraZeneca, Waltham, MA 02451, USA.
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7
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Liu D, Fan W, Xu Y, Yu S, Liu W, Guo Z, Huang W, Zhou Z, Hou S. Genome-wide association studies demonstrate that TASP1 contributes to increased muscle fiber diameter. Heredity (Edinb) 2021; 126:991-999. [PMID: 33767369 DOI: 10.1038/s41437-021-00425-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 03/01/2021] [Accepted: 03/09/2021] [Indexed: 12/13/2022] Open
Abstract
Muscle fiber diameter is an economically important trait because it affects meat yield and quality. However, the genetic basis underlying muscle fiber diameter has not been determined. In this study, we collected THREE muscular histological phenotypes in 479 ducks from an F2 segregating population generated by mallard × Pekin duck crosses. We performed genome-wide association studies (GWAS) and identified a quantitative trait locus (QTL) significantly associated with muscle fiber diameter on chromosome 3. Then, we discovered the selection signatures using the fixation index among 40 mallards and 30 Pekin ducks in this QTL region. Furthermore, we characterized the recombination event in this QTL region and identified a 6-kb block located on TASP1 that was significantly associated with muscle fiber diameter. Finally, five SNPs were screened as potential causative mutations within the 6-kb block. In conclusion, we demonstrated that TASP1 contributes to an increase in muscle fiber diameter, which helps to characterize muscle development and contributes to the genetic improvement of meat yield and quality in livestock.
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Affiliation(s)
- Dapeng Liu
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs; State Key Laboratory of Animal Nutrition; Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - Wenlei Fan
- College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, PR China
| | - Yaxi Xu
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs; State Key Laboratory of Animal Nutrition; Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - Simeng Yu
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs; State Key Laboratory of Animal Nutrition; Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - Wenjing Liu
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs; State Key Laboratory of Animal Nutrition; Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China.,College of Animal Science, Qingdao Agricultural University, Qingdao, PR China
| | - Zhanbao Guo
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs; State Key Laboratory of Animal Nutrition; Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - Wei Huang
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs; State Key Laboratory of Animal Nutrition; Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China
| | - Zhengkui Zhou
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs; State Key Laboratory of Animal Nutrition; Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China.
| | - Shuisheng Hou
- Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture and Rural Affairs; State Key Laboratory of Animal Nutrition; Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, PR China.
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8
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Liang L, Wang Z, Qu L, Huang W, Guo S, Guan X, Zhang W, Sun F, Yuan H, Zou H, Liu H, Yu Z. Single-molecule multiplexed profiling of protein-DNA complexes using magnetic tweezers. J Biol Chem 2021; 296:100327. [PMID: 33493518 PMCID: PMC7949110 DOI: 10.1016/j.jbc.2021.100327] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2020] [Revised: 01/10/2021] [Accepted: 01/21/2021] [Indexed: 01/14/2023] Open
Abstract
Epigenetics, such as the dynamic interplay between DNA methylation and demethylation, play diverse roles in critical cellular events. Enzymatic activity at CpG sites, where cytosines are methylated or demethylated, is known to be influenced by the density of CpGs, methylation states, and the flanking sequences of a CpG site. However, how the relevant enzymes are recruited to and recognize their target DNA is less clear. Moreover, although DNA-binding epigenetic enzymes are ideal targets for therapeutic intervention, these targets have been rarely exploited. Single-molecule techniques offer excellent capabilities to probe site-specific protein-DNA interactions and unravel the dynamics. Here, we develop a single-molecule approach that allows multiplexed profiling of protein-DNA complexes using magnetic tweezers. When a DNA hairpin with multiple binding sites is unzipping, strand separation pauses at the positions bound by a protein. We can thus measure site-specific binding probabilities and dissociation time directly. Taking the TET1 CXXC domain as an example, we show that TET1 CXXC binds multiple CpG motifs with various flanking nucleotides or different methylation patterns in an AT-rich DNA. We are able to establish for the first time, at nanometer resolution, that TET1 CXXC prefers G/C flanked CpG motif over C/G, A/T, or T/A flanked ones. CpG methylation strengthens TET1 CXXC recruitment but has little effect on dissociation time. Finally, we demonstrate that TET1 CXXC can distinguish five CpG clusters in a CpG island with crowded binding motifs. We anticipate that the feasibility of single-molecule multiplexed profiling assays will contribute to the understanding of protein-DNA interactions.
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Affiliation(s)
- Lin Liang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Zeyu Wang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Lihua Qu
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Wei Huang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Shuang Guo
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Xiangchen Guan
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China
| | - Wei Zhang
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Institute of Modern Optics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin, China
| | - Fuping Sun
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Institute of Modern Optics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin, China
| | - Hongrui Yuan
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Institute of Modern Optics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin, China
| | - Huiru Zou
- Central Laboratory of Tianjin Stomatological Hospital, The Affiliated Stomatological Hospital of Nankai University, Tianjin, China
| | - Haitao Liu
- Tianjin Key Laboratory of Optoelectronic Sensor and Sensing Network Technology, Institute of Modern Optics, College of Electronic Information and Optical Engineering, Nankai University, Tianjin, China
| | - Zhongbo Yu
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy, Nankai University, Tianjin, China.
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9
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Milan T, Celton M, Lagacé K, Roques É, Safa-Tahar-Henni S, Bresson E, Bergeron A, Hebert J, Meshinchi S, Cellot S, Barabé F, Wilhelm BT. Epigenetic changes in human model KMT2A leukemias highlight early events during leukemogenesis. Haematologica 2020; 107:86-99. [PMID: 33375773 PMCID: PMC8719083 DOI: 10.3324/haematol.2020.271619] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2020] [Indexed: 11/26/2022] Open
Abstract
Chromosomal translocations involving the KMT2A gene are among the most common genetic alterations found in pediatric acute myeloid leukemias although the molecular mechanisms that initiate the disease remain incompletely defined. To elucidate these initiating events we used a human model system of acute myeloid leukemia driven by the KMT2A-MLLT3 (KM3) fusion. More specifically, we investigated changes in DNA methylation, histone modifications, and chromatin accessibility at each stage of our model system and correlated these with expression changes. We observed the development of a pronounced hypomethyl - ation phenotype in the early stages of leukemic transformation after KM3 addition along with loss of expression of stem-cell-associated genes and skewed expression of other genes, such as S100A8/9, implicated in leukemogenesis. In addition, early increases in the expression of the lysine demethylase KDM4B was functionally linked to these expression changes as well as other key transcription factors. Remarkably, our ATAC-sequencing data showed that there were relatively few leukemia-specific changes and that the vast majority corresponded to open chromatin regions and transcription factor clusters previously observed in other cell types. Integration of the gene expression and epigenetic changes revealed that the adenylate cyclase gene ADCY9 is an essential gene in KM3-acute myeloid leukemia, and suggested the potential for autocrine signaling through the chemokine receptor CCR1 and CCL23 ligand. Collectively, our results suggest that KM3 induces subtle changes in the epigenome while co-opting the normal transcriptional machinery to drive leukemogenesis.
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Affiliation(s)
- Thomas Milan
- Laboratory for High Throughput Biology, Institute for Research in Immunology and Cancer, Montréal, QC
| | - Magalie Celton
- Laboratory for High Throughput Biology, Institute for Research in Immunology and Cancer, Montréal, QC
| | - Karine Lagacé
- Laboratory for High Throughput Biology, Institute for Research in Immunology and Cancer, Montréal, QC
| | - Élodie Roques
- Laboratory for High Throughput Biology, Institute for Research in Immunology and Cancer, Montréal, QC
| | - Safia Safa-Tahar-Henni
- Laboratory for High Throughput Biology, Institute for Research in Immunology and Cancer, Montréal, QC
| | - Eva Bresson
- Centre de recherche en infectiologie du CHUL, Centre de recherche du CHU de Québec - Université Laval, Québec City, QC, Canada; CHU de Québec - Université Laval - Hôpital Enfant-Jésus; Québec City, QC, Canada; Department of Medicine, Université Laval, Quebec City, QC
| | - Anne Bergeron
- Centre de recherche en infectiologie du CHUL, Centre de recherche du CHU de Québec - Université Laval, Québec City, QC, Canada; CHU de Québec - Université Laval - Hôpital Enfant-Jésus; Québec City, QC, Canada; Department of Medicine, Université Laval, Quebec City, QC
| | - Josée Hebert
- Division of Hematology-Oncology and Leukemia Cell Bank of Quebec, Maisonneuve-Rosemont Hospital, Montréal, QC, Canada; Department of Medicine, Université de Montréal, Montréal, QC
| | - Soheil Meshinchi
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Sonia Cellot
- Department of pediatrics, division of Hematology, Ste-Justine Hospital, Montréal, QC
| | - Frédéric Barabé
- Centre de recherche en infectiologie du CHUL, Centre de recherche du CHU de Québec - Université Laval, Québec City, QC, Canada; CHU de Québec - Université Laval - Hôpital Enfant-Jésus; Québec City, QC, Canada; Department of Medicine, Université Laval, Quebec City, QC
| | - Brian T Wilhelm
- Laboratory for High Throughput Biology, Institute for Research in Immunology and Cancer, Montréal, QC, Canada; Department of Medicine, Université de Montréal, Montréal, QC.
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10
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Han C, Sun LY, Wang WT, Sun YM, Chen YQ. Non-coding RNAs in cancers with chromosomal rearrangements: the signatures, causes, functions and implications. J Mol Cell Biol 2020; 11:886-898. [PMID: 31361891 PMCID: PMC6884712 DOI: 10.1093/jmcb/mjz080] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Revised: 05/24/2019] [Accepted: 05/26/2019] [Indexed: 12/25/2022] Open
Abstract
Chromosomal translocation leads to the juxtaposition of two otherwise separate DNA loci, which could result in gene fusion. These rearrangements at the DNA level are catastrophic events and often have causal roles in tumorigenesis. The oncogenic DNA messages are transferred to RNA molecules, which are in most cases translated into cancerous fusion proteins. Gene expression programs and signaling pathways are altered in these cytogenetically abnormal contexts. Notably, non-coding RNAs have attracted increasing attention and are believed to be tightly associated with chromosome-rearranged cancers. These RNAs not only function as modulators in downstream pathways but also directly affect chromosomal translocation or the associated products. This review summarizes recent research advances on the relationship between non-coding RNAs and chromosomal translocations and on diverse functions of non-coding RNAs in cancers with chromosomal rearrangements.
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Affiliation(s)
- Cai Han
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, Sun Yat-sen University, Guangzhou 510275, China
| | - Lin-Yu Sun
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, Sun Yat-sen University, Guangzhou 510275, China
| | - Wen-Tao Wang
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, Sun Yat-sen University, Guangzhou 510275, China
| | - Yu-Meng Sun
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, Sun Yat-sen University, Guangzhou 510275, China
| | - Yue-Qin Chen
- MOE Key Laboratory of Gene Function and Regulation, State Key Laboratory for Biocontrol, Sun Yat-sen University, Guangzhou 510275, China
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11
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The Influence of Methylating Mutations on Acute Myeloid Leukemia: Preliminary Analysis on 56 Patients. Diagnostics (Basel) 2020; 10:diagnostics10050263. [PMID: 32365516 PMCID: PMC7277399 DOI: 10.3390/diagnostics10050263] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2020] [Revised: 04/26/2020] [Accepted: 04/28/2020] [Indexed: 11/18/2022] Open
Abstract
Acute myeloid leukemia (AML) is a hematologic malignancy characterized by abnormal proliferation and a lack of differentiation of myeloid blasts. Considering the dismal prognosis this disease presents, several efforts have been made to better classify it and offer a tailored treatment to each subtype. This has been formally done by the World Health Organization (WHO) with the AML classification schemes from 2008 and 2016. Nonetheless, there are still mutations that are not currently included in the WHO AML classification, as in the case of some mutations that influence methylation. In this regard, the present study aimed to determine if some of the mutations that influence DNA methylation can be clustered together regarding methylation, expression, and clinical profile. Data from the TCGA LAML cohort were downloaded via cBioPortal. The analysis was performed using R 3.5.2, and the necessary packages for classical statistics, dimensionality reduction, and machine learning. We included only patients that presented mutations in DNMT3A, TET2, IDH1/2, ASXL1, WT1, and KMT2A. Afterwards, mutations that were present in too few patients were removed from the analysis, thus including a total of 57 AML patients. We observed that regarding expression, methylation, and clinical profile, patients with mutated TET2, IDH1/2, and WT1 presented a high degree of similarity, indicating the equivalence that these mutations present between themselves. Nonetheless, we did not observe this similarity between DNMT3A- and KMT2A-mutated AML. Moreover, when comparing the hypermethylating group with the hypomethylating one, we also observed important differences regarding expression, methylation, and clinical profile. In the current manuscript we offer additional arguments for the similarity of the studied hypermethylating mutations and suggest that those should be clustered together in further classifications. The hypermethylating and hypomethylating groups formed above were shown to be different from each other considering overall survival, methylation profile, expression profile, and clinical characteristics. In this manuscript, we present additional arguments for the similarity of the effect generated by TET2, IDH1/2, and WT1 mutations in AML patients. Thus, we hypothesize that hypermethylating mutations skew the AML cells to a similar phenotype with a possible sensitivity to hypermethylating agents.
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12
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Insights on the regulation of the MLL/SET1 family histone methyltransferases. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2020; 1863:194561. [PMID: 32304759 DOI: 10.1016/j.bbagrm.2020.194561] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 03/07/2020] [Accepted: 04/09/2020] [Indexed: 01/09/2023]
Abstract
In eukaryotes, histone H3K4 methylation by the MLL/SET1 family histone methyltransferases is enriched at transcription regulatory elements including gene promoters and enhancers. The level of H3K4 methylation is highly correlated with transcription activation and is one of the most frequently used histone post-translational modifications to predict transcriptional outcome. Recently, it has been shown that rearrangement of the cellular landscape of H3K4 mono-methylation at distal enhancers precedes cell fate transition and is used for identification of novel regulatory elements for development and disease progression. Similarly, broad H3K4 tri-methylation regions have also been used to predict intrinsic tumor suppression properties of regulator regions in a variety of cellular models. Understanding the regulation for how H3K4 methylation is deposited and regulated is of paramount importance. In this review, we will discuss new findings on how the MLL/SET1 family enzymes are regulated on chromatin and their potential functional and regulatory implications. 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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13
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Ma X, Zhu M, Liu J, Li X, Qu L, Liang L, Huang W, Wang J, Li N, Chen JH, Zhang W, Yu Z. Interactions between PHD3-Bromo of MLL1 and H3K4me3 Revealed by Single-Molecule Magnetic Tweezers in a Parallel DNA Circuit. Bioconjug Chem 2019; 30:2998-3006. [PMID: 31714753 DOI: 10.1021/acs.bioconjchem.9b00665] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Single-molecule force spectroscopy is a powerful tool to directly measure protein-protein interactions (PPI). The high specificity and precision of PPI measurements made it possible to reveal detailed mechanisms of intermolecular interactions. However, protein aggregation due to specific or nonspecific interactions is among the most challenging problems in PPI examination. Here, we propose a strategy of a parallel DNA circuit to probe PPI using single-molecule magnetic tweezers. In contrast to PPI examination using atomic force microscopy, microspheres as probes used in magnetic tweezers avoided the single-probe issue of a cantilever. Negatively charged DNA as a linker circumvented the severe aggregation in the PPI construct with a protein linker. The unnatural amino acid encoded in proteins of interest expanded the choices of biorthogonal conjugation. We demonstrated how to apply our strategy to probe the PPI between the PHD3-Bromo and the histone H3 methylated at K4, a critical epigenetic event in leukemia development. We found a rupture force of 12 pN for breaking the PPI, which is much higher than that required to peel DNA off from a nucleosome, 3 pN. We expect that our methods will make PPI measurements of mechanics and kinetics with great precision, facilitating PPI-related research, e.g., PPI-targeted drug discovery.
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Affiliation(s)
- Xiaofeng Ma
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
| | - Manning Zhu
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
| | - Jianyu Liu
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Changchun 130012 , China
| | - Xu Li
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
| | - Lihua Qu
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
| | - Lin Liang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
| | - Wei Huang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
| | - Junli Wang
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
| | - Ning Li
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
| | - Jun-Hu Chen
- National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, WHO Collaborating Center for Tropical Diseases, National Center for International Research on Tropical Diseases , Key Laboratory of Parasite and Vector Biology, Ministry of Health , Shanghai 200025 , China
| | - Wenke Zhang
- State Key Laboratory of Supramolecular Structure and Materials, College of Chemistry , Jilin University , Changchun 130012 , China
| | - Zhongbo Yu
- State Key Laboratory of Medicinal Chemical Biology, College of Pharmacy , Nankai University , 38 Tongyan Rd , Tianjin 300353 , China
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14
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Hurtz C, Chan LN, Geng H, Ballabio E, Xiao G, Deb G, Khoury H, Chen CW, Armstrong SA, Chen J, Ernst P, Melnick A, Milne T, Müschen M. Rationale for targeting BCL6 in MLL-rearranged acute lymphoblastic leukemia. Genes Dev 2019; 33:1265-1279. [PMID: 31395741 PMCID: PMC6719625 DOI: 10.1101/gad.327593.119] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 07/02/2019] [Indexed: 12/27/2022]
Abstract
Chromosomal rearrangements of the mixed lineage leukemia (MLL) gene occur in ∼10% of B-cell acute lymphoblastic leukemia (B-ALL) and define a group of patients with dismal outcomes. Immunohistochemical staining of bone marrow biopsies from most of these patients revealed aberrant expression of BCL6, a transcription factor that promotes oncogenic B-cell transformation and drug resistance in B-ALL. Our genetic and ChIP-seq (chromatin immunoprecipitation [ChIP] combined with high-throughput sequencing) analyses showed that MLL-AF4 and MLL-ENL fusions directly bound to the BCL6 promoter and up-regulated BCL6 expression. While oncogenic MLL fusions strongly induced aberrant BCL6 expression in B-ALL cells, germline MLL was required to up-regulate Bcl6 in response to physiological stimuli during normal B-cell development. Inducible expression of Bcl6 increased MLL mRNA levels, which was reversed by genetic deletion and pharmacological inhibition of Bcl6, suggesting a positive feedback loop between MLL and BCL6. Highlighting the central role of BCL6 in MLL-rearranged B-ALL, conditional deletion and pharmacological inhibition of BCL6 compromised leukemogenesis in transplant recipient mice and restored sensitivity to vincristine chemotherapy in MLL-rearranged B-ALL patient samples. Oncogenic MLL fusions strongly induced transcriptional activation of the proapoptotic BH3-only molecule BIM, while BCL6 was required to curb MLL-induced expression of BIM. Notably, peptide (RI-BPI) and small molecule (FX1) BCL6 inhibitors derepressed BIM and synergized with the BH3-mimetic ABT-199 in eradicating MLL-rearranged B-ALL cells. These findings uncover MLL-dependent transcriptional activation of BCL6 as a previously unrecognized requirement of malignant transformation by oncogenic MLL fusions and identified BCL6 as a novel target for the treatment of MLL-rearranged B-ALL.
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Affiliation(s)
- Christian Hurtz
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA.,Department of Laboratory Medicine, University of California at San Francisco, San Francisco, California 94143, USA
| | - Lai N Chan
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA.,Department of Laboratory Medicine, University of California at San Francisco, San Francisco, California 94143, USA
| | - Huimin Geng
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA.,Department of Laboratory Medicine, University of California at San Francisco, San Francisco, California 94143, USA
| | - Erica Ballabio
- Medical Research Council (MRC) Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Gang Xiao
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA.,Department of Laboratory Medicine, University of California at San Francisco, San Francisco, California 94143, USA
| | - Gauri Deb
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA
| | - Haytham Khoury
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA
| | - Chun-Wei Chen
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA
| | - Scott A Armstrong
- Department of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts 02115, USA
| | - Jianjun Chen
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA
| | - Patricia Ernst
- Department of Pediatrics, University of Colorado, Denver, Colorado 80045, USA
| | - Ari Melnick
- Department of Medicine, Weill Cornell Medical College, New York, New York 10065, USA.,Department of Pharmacology, Weill Cornell Medical College, New York, New York 10065, USA
| | - Thomas Milne
- Medical Research Council (MRC) Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford OX3 9DS, United Kingdom
| | - Markus Müschen
- Department of Systems Biology, City of Hope Comprehensive Cancer Center, Monrovia, California 91016, USA.,Department of Laboratory Medicine, University of California at San Francisco, San Francisco, California 94143, USA
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15
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Alsayegh K, Cortés-Medina LV, Ramos-Mandujano G, Badraiq H, Li M. Hematopoietic Differentiation of Human Pluripotent Stem Cells: HOX and GATA Transcription Factors as Master Regulators. Curr Genomics 2019; 20:438-452. [PMID: 32194342 PMCID: PMC7062042 DOI: 10.2174/1389202920666191017163837] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 09/04/2019] [Accepted: 09/27/2019] [Indexed: 02/07/2023] Open
Abstract
Numerous human disorders of the blood system would directly or indirectly benefit from therapeutic approaches that reconstitute the hematopoietic system. Hematopoietic stem cells (HSCs), either from matched donors or ex vivo manipulated autologous tissues, are the most used cellular source of cell therapy for a wide range of disorders. Due to the scarcity of matched donors and the difficulty of ex vivo expansion of HSCs, there is a growing interest in harnessing the potential of pluripotent stem cells (PSCs) as a de novo source of HSCs. PSCs make an ideal source of cells for regenerative medicine in general and for treating blood disorders in particular because they could expand indefinitely in culture and differentiate to any cell type in the body. However, advancement in deriving functional HSCs from PSCs has been slow. This is partly due to an incomplete understanding of the molecular mechanisms underlying normal hematopoiesis. In this review, we discuss the latest efforts to generate human PSC (hPSC)-derived HSCs capable of long-term engraftment. We review the regulation of the key transcription factors (TFs) in hematopoiesis and hematopoietic differentiation, the Homeobox (HOX) and GATA genes, and the interplay between them and microRNAs. We also propose that precise control of these master regulators during the course of hematopoietic differentiation is key to achieving functional hPSC-derived HSCs.
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Affiliation(s)
- Khaled Alsayegh
- King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Sciences, Jeddah, Saudi Arabia.,Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Lorena V Cortés-Medina
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Gerardo Ramos-Mandujano
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Heba Badraiq
- King Abdullah International Medical Research Centre, King Saud bin Abdulaziz University for Health Sciences, Jeddah, Saudi Arabia
| | - Mo Li
- Biological and Environmental Science and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
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16
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Meyer SE, Muench DE, Rogers AM, Newkold TJ, Orr E, O'Brien E, Perentesis JP, Doench JG, Lal A, Morris PJ, Thomas CJ, Lieberman J, McGlinn E, Aronow BJ, Salomonis N, Grimes HL. miR-196b target screen reveals mechanisms maintaining leukemia stemness with therapeutic potential. J Exp Med 2018; 215:2115-2136. [PMID: 29997117 PMCID: PMC6080909 DOI: 10.1084/jem.20171312] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 04/30/2018] [Accepted: 06/26/2018] [Indexed: 01/02/2023] Open
Abstract
We have shown that antagomiR inhibition of miRNA miR-21 and miR-196b activity is sufficient to ablate MLL-AF9 leukemia stem cells (LSC) in vivo. Here, we used an shRNA screening approach to mimic miRNA activity on experimentally verified miR-196b targets to identify functionally important and therapeutically relevant pathways downstream of oncogenic miRNA in MLL-r AML. We found Cdkn1b (p27Kip1) is a direct miR-196b target whose repression enhanced an embryonic stem cell-like signature associated with decreased leukemia latency and increased numbers of leukemia stem cells in vivo. Conversely, elevation of p27Kip1 significantly reduced MLL-r leukemia self-renewal, promoted monocytic differentiation of leukemic blasts, and induced cell death. Antagonism of miR-196b activity or pharmacologic inhibition of the Cks1-Skp2-containing SCF E3-ubiquitin ligase complex increased p27Kip1 and inhibited human AML growth. This work illustrates that understanding oncogenic miRNA target pathways can identify actionable targets in leukemia.
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MESH Headings
- Animals
- Carcinogenesis/genetics
- Carcinogenesis/pathology
- Cell Differentiation/genetics
- Cell Line, Tumor
- Cell Proliferation/genetics
- Cell Survival/genetics
- Chromosomes, Human, Pair 11/genetics
- Cyclin-Dependent Kinase Inhibitor p27/metabolism
- Cyclin-Dependent Kinases/metabolism
- Cyclins/metabolism
- Embryonic Stem Cells/metabolism
- Gene Expression Regulation, Leukemic
- Humans
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myeloid, Acute/pathology
- Leukemia, Myeloid, Acute/therapy
- Mice, Inbred C57BL
- MicroRNAs/genetics
- MicroRNAs/metabolism
- Neoplastic Stem Cells/metabolism
- Neoplastic Stem Cells/pathology
- Oncogenes
- RNA, Small Interfering/metabolism
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Affiliation(s)
- Sara E Meyer
- Division of Immunobiology and Center for Systems Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - David E Muench
- Division of Immunobiology and Center for Systems Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Andrew M Rogers
- Division of Immunobiology and Center for Systems Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Tess J Newkold
- Division of Immunobiology and Center for Systems Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Emily Orr
- Division of Immunobiology and Center for Systems Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Eric O'Brien
- Division of Oncology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - John P Perentesis
- Division of Oncology, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | | | - Ashish Lal
- Regulatory RNAs and Cancer Section, Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD
| | - Patrick J Morris
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Craig J Thomas
- Division of Preclinical Innovation, National Center for Advancing Translational Sciences, National Institutes of Health, Rockville, MD
| | - Judy Lieberman
- Program in Cellular and Molecular Medicine, Boston Children's Hospital, Boston, MA
- Department of Pediatrics, Harvard Medical School, Boston, MA
| | - Edwina McGlinn
- EMBL Australia, Australian Regenerative Medicine Institute, Monash University, Clayton, Victoria, Australia
| | - Bruce J Aronow
- Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - Nathan Salomonis
- Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
| | - H Leighton Grimes
- Division of Immunobiology and Center for Systems Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH
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17
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Modes of Interaction of KMT2 Histone H3 Lysine 4 Methyltransferase/COMPASS Complexes with Chromatin. Cells 2018; 7:cells7030017. [PMID: 29498679 PMCID: PMC5870349 DOI: 10.3390/cells7030017] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Revised: 02/22/2018] [Accepted: 02/27/2018] [Indexed: 02/07/2023] Open
Abstract
Regulation of gene expression is achieved by sequence-specific transcriptional regulators, which convey the information that is contained in the sequence of DNA into RNA polymerase activity. This is achieved by the recruitment of transcriptional co-factors. One of the consequences of co-factor recruitment is the control of specific properties of nucleosomes, the basic units of chromatin, and their protein components, the core histones. The main principles are to regulate the position and the characteristics of nucleosomes. The latter includes modulating the composition of core histones and their variants that are integrated into nucleosomes, and the post-translational modification of these histones referred to as histone marks. One of these marks is the methylation of lysine 4 of the core histone H3 (H3K4). While mono-methylation of H3K4 (H3K4me1) is located preferentially at active enhancers, tri-methylation (H3K4me3) is a mark found at open and potentially active promoters. Thus, H3K4 methylation is typically associated with gene transcription. The class 2 lysine methyltransferases (KMTs) are the main enzymes that methylate H3K4. KMT2 enzymes function in complexes that contain a necessary core complex composed of WDR5, RBBP5, ASH2L, and DPY30, the so-called WRAD complex. Here we discuss recent findings that try to elucidate the important question of how KMT2 complexes are recruited to specific sites on chromatin. This is embedded into short overviews of the biological functions of KMT2 complexes and the consequences of H3K4 methylation.
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18
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Li M, Li X, Zhuang Y, Wang Y, Burow ME, Collins-Burow B, Xue M, Song C, Shan B. Induction of HOXA9 expression in three-dimensional organotypic culture of the Claudin-low breast cancer cells. Oncotarget 2018; 7:51503-51514. [PMID: 27409175 PMCID: PMC5239492 DOI: 10.18632/oncotarget.10491] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 06/29/2016] [Indexed: 01/05/2023] Open
Abstract
The gene expression signatures of the molecular intrinsic subtypes of breast cancer are regulated by epigenetic mechanisms such as methylation of CpG islands in gene promoters. Epigenetic codes can be regulated by the tumor microenvironment. The Claudin-low subtype is associated with triple-negative invasive ductal carcinomas in patients. Herein we explored epigenetic regulation of gene expression in the Claudin-low breast cancer cells by extracellular matrix (ECM), a key component of the tumor microenvironment. We modeled attachment to ECM using laminin rich ECM three-dimensional organotypic culture (lrECM 3D). In 2D and lrECM 3D cultures we examined expression of the homeobox (HOX) genes that epigenetically regulated in development and cancer. We demonstrated induction of the selected HOX genes in lrECM 3D culture of the Claudin-low breast cancer cells MDA-MB-231 and Hs578T. In particular activation of HOXA9 expression in lrECM 3D culture required binding of bromodomain containing 4 to the HOXA9 promoter and involved CpG hypomethylation. Our findings warrant further investigation of the ECM-regulated epigenetic coding of gene expression in the Claudin-low breast cancer.
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Affiliation(s)
- Miao Li
- Department of Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - Xi Li
- Department of Sports Medicine and Joint Surgery, The People's Hospital of Liaoning Province, Shenyang, China
| | - Yan Zhuang
- Department of Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | - Yan Wang
- Department of Biological Engineering, Zunyi Medical College Zhuhai Campus, Zhuhai, China
| | - Matthew E Burow
- Department of Medicine, Tulane University School of Medicine, New Orleans, LA, USA
| | | | - Min Xue
- Department of Physiology, Xuzhou Medical College, Xuzhou, China
| | - Chengjie Song
- Department of Physiology, Xuzhou Medical College, Xuzhou, China
| | - Bin Shan
- Department of Biomedical Sciences, Elson S. Floyd College of Medicine, Washington State University Spokane, Spokane, WA, USA
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19
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Saul MJ, Groher F, Hegewald AB, Müller-McNicoll M, Marschalek R, Suess B, Steinhilber D. TGFβ/SMAD signalling modulates MLL and MLL-AF4 mediated 5-lipoxygenase promoter activation. Prostaglandins Other Lipid Mediat 2017; 133:60-67. [DOI: 10.1016/j.prostaglandins.2017.07.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Revised: 06/28/2017] [Accepted: 07/31/2017] [Indexed: 01/11/2023]
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20
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Huang YC, Lin SJ, Shih HY, Chou CH, Chu HH, Chiu CC, Yuh CH, Yeh TH, Cheng YC. Epigenetic regulation of NOTCH1 and NOTCH3 by KMT2A inhibits glioma proliferation. Oncotarget 2017; 8:63110-63120. [PMID: 28968975 PMCID: PMC5609907 DOI: 10.18632/oncotarget.18668] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Accepted: 05/22/2017] [Indexed: 02/06/2023] Open
Abstract
Glioblastomas are among the most fatal brain tumors; however, the molecular determinants of their tumorigenic behavior are not adequately defined. In this study, we analyzed the role of KMT2A in the glioblastoma cell line U-87 MG. KMT2A knockdown promoted cell proliferation. Moreover, it increased the DNA methylation of NOTCH1 and NOTCH3 and reduced the expression of NOTCH1 and NOTCH3. NOTCH1 or NOTCH3 activation inhibited U-87 MG cell proliferation, whereas NOTCH1 and NOTCH3 inhibition by shRNAs induced cell proliferation, thus demonstrating the tumor-suppressive ability of NOTCH1 and NOTCH3 in U-87 MG cells. The induced cell proliferation caused by KMT2A knockdown could be nullified by using either constitutively active NOTCH1 or constitutively active NOTCH3. This result demonstrates that KMT2A positively regulates NOTCH1 and NOTCH3 and that this mechanism is essential for inhibiting the U-87 MG cell proliferation. The role of KMT2A knockdown in promoting tumor growth was further confirmed in vivo by transplanting U-87 MG cells into the brains of zebrafish larvae. In conclusion, we identified KMT2A-NOTCH as a negative regulatory cascade for glioblastoma cell proliferation, and this result provides important information for KMT2A- or NOTCH-targeted therapeutic strategies for brain tumors.
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Affiliation(s)
- Yin-Cheng Huang
- College of Medicine, Chang Gung University, Taoyuan, Taiwan.,Department of Neurosurgery, Chang Gung Memorial Hospital at Linkou Medical Center, Taoyuan, Taiwan
| | - Sheng-Jia Lin
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang-Gung University, Taoyuan, Taiwan
| | - Hung-Yu Shih
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang-Gung University, Taoyuan, Taiwan
| | - Chung-Han Chou
- School of Medicine, College of Medicine, Chang-Gung University, Taoyuan, Taiwan
| | - Hsiao-Han Chu
- School of Medicine, College of Medicine, Chang-Gung University, Taoyuan, Taiwan
| | - Ching-Chi Chiu
- Neuroscience Research Center, Chang Gung Memorial Hospital at Linkou Medical Center, Taoyuan, Taiwan
| | - Chiou-Hwa Yuh
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan, Taiwan
| | - Tu-Hsueh Yeh
- Neuroscience Research Center, Chang Gung Memorial Hospital at Linkou Medical Center, Taoyuan, Taiwan.,Department of Neurology, Taipei Medical University Hospital, Taipei, Taiwan.,School of Medicine, Taipei Medical University, Taipei, Taiwan
| | - Yi-Chuan Cheng
- Graduate Institute of Biomedical Sciences, College of Medicine, Chang-Gung University, Taoyuan, Taiwan.,Neuroscience Research Center, Chang Gung Memorial Hospital at Linkou Medical Center, Taoyuan, Taiwan
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21
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Mian YA, Zeleznik-Le NJ. The miR-17∼92 cluster contributes to MLL leukemia through the repression of MEIS1 competitor PKNOX1. Leuk Res 2016; 46:51-60. [PMID: 27123834 DOI: 10.1016/j.leukres.2016.04.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Revised: 04/06/2016] [Accepted: 04/07/2016] [Indexed: 12/19/2022]
Abstract
Mixed lineage leukemias have a relatively poor prognosis and arise as a result of translocations between the MLL(KMT2A) gene and one of multiple partner genes. Downstream targets of MLL are aberrantly upregulated and include the developmentally important HOX genes and MEIS1, as well as multiple microRNAs (miRNAs), including the miR-17∼92 cluster. Here we examined the contribution of specific miRNAs to MLL leukemias through knockdown studies utilizing custom anti-microRNA oligonucleotides. Combinatorial treatment against miR-17-5p and miR-19a-3p of the miR-17∼92 cluster dramatically reduces colony forming ability of MLL-fusion containing cell lines relative to non-MLL acute myeloid leukemia (AML) controls. To determine the mechanism by which these miRNAs contribute to leukemia, we validated PKNOX1 as a target of both miR-17-5p and miR-19a-3p. MEIS1 and PKNOX1 are TALE domain proteins that participate in ternary complexes with HOX and PBX partners. Here we establish the competitive relationship between PKNOX1 and MEIS1 in PBX-containing complex formation and determine the antagonistic role of PKNOX1 to leukemia in a murine MLL-AF9 model. These data implicate the miR-17∼92 cluster as part of a regulatory mechanism necessary to maintain MEIS1/HOXA9 -mediated transformation in MLL leukemia, indicating that targeting multiple non-homologous miRNAs may be utilized as a novel therapeutic regimen.
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Affiliation(s)
- Yousaf A Mian
- Molecular Biology Program, Loyola University Chicago, Maywood, IL 60153, United States
| | - Nancy J Zeleznik-Le
- Molecular Biology Program, Loyola University Chicago, Maywood, IL 60153, United States; Department of Medicine, Loyola University Chicago, Maywood, IL 60153, United States.
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22
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Epigenetic regulation of cyclooxygenase-2 by methylation of c8orf4 in pulmonary fibrosis. Clin Sci (Lond) 2016; 130:575-86. [PMID: 26744410 PMCID: PMC4782165 DOI: 10.1042/cs20150697] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 01/07/2016] [Indexed: 02/01/2023]
Abstract
The present study demonstrates that hypermethylation and silencing of chromosome 8 open reading frame 4 (thyroid cancer protein 1, TC-1) (c8orf4), a transcriptional regulator of cyclooxygenase-2 (COX-2), is a major contributor to failure of fibroblasts to up-regulate COX-2 in pulmonary fibrosis. DNA methyltransferase (DNMT) inhibition reduces c8orf4 methylation, restores COX-2 expression and normalizes fibroblast function. Fibroblasts derived from the lungs of patients with idiopathic pulmonary fibrosis (IPF) and systemic sclerosis (SSc) produce low levels of prostaglandin (PG) E2, due to a limited capacity to up-regulate cyclooxygenase-2 (COX-2). This deficiency contributes functionally to the fibroproliferative state, however the mechanisms responsible are incompletely understood. In the present study, we examined whether the reduced level of COX-2 mRNA expression observed in fibrotic lung fibroblasts is regulated epigenetically. The DNA methylation inhibitor, 5-aza-2′-deoxycytidine (5AZA) restored COX-2 mRNA expression by fibrotic lung fibroblasts dose dependently. Functionally, this resulted in normalization of fibroblast phenotype in terms of PGE2 production, collagen mRNA expression and sensitivity to apoptosis. COX-2 methylation assessed by bisulfite sequencing and methylation microarrays was not different in fibrotic fibroblasts compared with controls. However, further analysis of the methylation array data identified a transcriptional regulator, chromosome 8 open reading frame 4 (thyroid cancer protein 1, TC-1) (c8orf4), which is hypermethylated and down-regulated in fibrotic fibroblasts compared with controls. siRNA knockdown of c8orf4 in control fibroblasts down-regulated COX-2 and PGE2 production generating a phenotype similar to that observed in fibrotic lung fibroblasts. Chromatin immunoprecipitation demonstrated that c8orf4 regulates COX-2 expression in lung fibroblasts through binding of the proximal promoter. We conclude that the decreased capacity of fibrotic lung fibroblasts to up-regulate COX-2 expression and COX-2-derived PGE2 synthesis is due to an indirect epigenetic mechanism involving hypermethylation of the transcriptional regulator, c8orf4.
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Sakamoto A, Akiyama Y, Shimada S, Zhu WG, Yuasa Y, Tanaka S. DNA Methylation in the Exon 1 Region and Complex Regulation of Twist1 Expression in Gastric Cancer Cells. PLoS One 2015; 10:e0145630. [PMID: 26695186 PMCID: PMC4687923 DOI: 10.1371/journal.pone.0145630] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Accepted: 12/06/2015] [Indexed: 02/06/2023] Open
Abstract
Twist1 overexpression is frequently observed in various cancers including gastric cancer (GC). Although DNA methylation of the Twist1 gene has been reported in cancer cells, the mechanisms underlying transcriptional activation remain uncertain. In this study, we first examined epigenetic alterations of the Twist1 using Twist1 transcription-positive and -negative cell lines that are derived from our established diffuse-type GC mouse model. Treatment with a DNA demethylation agent 5-aza-dC re-activated Twist1 expression in Twist1 expression-negative GC cells. According to methylation-specific PCR and bisulfite sequencing analysis, methylation at the CpG-rich region within Twist1 coding exon 1, rather than its promoter region, was tightly linked to transcriptional silencing of the Twist1 expression in mouse GC cells. Chromatin immunoprecipitation assays revealed that active histone mark H3K4me3 was enriched in Twist1 expression-positive cells, and inactive histone mark H3K9me3 was enriched in Twist1 expression-negative cells. The expression levels of Suv39h1 and Suv39h2, histone methyltransferases for H3K9me3, were inversely correlated with Twist1 expression, and knockdown of Suv39h1 or Suv39h2 induced Twist1 expression. Moreover, Sp1 transcription factor bound to the exon 1 CpG-rich region in Twist1 expression-positive cell lines, and Twist1 expression was diminished by mithramycin, which that interferes with Sp1 binding to CpG-rich regulatory sequences. Our studies suggested that the Twist1 transcription in GC cells might be regulated through potential cooperation of DNA methylation, histone modification in complex with Sp1 binding to CpG-rich regions within the exon 1 region.
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Affiliation(s)
- Ayuna Sakamoto
- Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Yoshimitsu Akiyama
- Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- * E-mail: ;
| | - Shu Shimada
- Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Wei-Guo Zhu
- Department of Biochemistry and Molecular Biology, Peking University Health Science Center, Beijing, 100191, China
| | - Yasuhito Yuasa
- Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
| | - Shinji Tanaka
- Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, Japan
- * E-mail: ;
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Bina M, Wyss P. Impact of the MLL1 morphemes on codon utilization and preservation in CpG Islands. Biopolymers 2015; 103:480-90. [PMID: 25991579 DOI: 10.1002/bip.22681] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2014] [Revised: 05/04/2015] [Accepted: 05/13/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Minou Bina
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907
| | - Phillip Wyss
- Department of Chemistry, Purdue University, West Lafayette, IN, 47907
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25
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Zhang T, Walensky LD, Saghatelian A. A nonapoptotic role for BAX and BAK in eicosanoid metabolism. ACS Chem Biol 2015; 10:1398-403. [PMID: 25815636 DOI: 10.1021/acschembio.5b00168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
BCL-2 proteins are key regulators of programmed cell death. The interplay between pro and antiapoptotic BCL-2 members has important roles in many cancers. In addition to their apoptotic function, recent evidence supports key nonapoptotic roles for several BCL-2 proteins. We used an unbiased lipidomics strategy to reveal that the proapoptotic proteins BAX, and to a lesser extent BAK, regulate the cellular inflammatory response by mediating COX-2 expression and prostaglandin biosynthesis. COX-2 upregulation in response to the bacterial endotoxin lipopolysaccharide is blunted in the absence of BAX, and Bax(-/-) mouse embryonic fibroblasts display altered kinetics of NFκB and MAPK signaling following endotoxin treatment. Our approach uncovers a novel, nonapoptotic function for BAX in regulation of the cellular inflammatory response and suggests that inflammation and apoptosis are more tightly connected than previously anticipated.
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Affiliation(s)
- Tejia Zhang
- Clayton
Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California 92037, United States
| | - Loren D. Walensky
- Department
of Pediatric Oncology, Dana-Farber Cancer Institute and Boston Children’s
Hospital, Harvard Medical School, Boston, Massachusetts 02215, United States
- Linde
Program in Cancer Chemical Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, United States
| | - Alan Saghatelian
- Clayton
Foundation Laboratories for Peptide Biology, Salk Institute for Biological Studies, La Jolla, California 92037, United States
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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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Karamitros D, Patmanidi AL, Kotantaki P, Potocnik AJ, Bähr-Ivacevic T, Benes V, Lygerou Z, Kioussis D, Taraviras S. Geminin deletion increases the number of fetal hematopoietic stem cells by affecting the expression of key transcription factors. Development 2015; 142:70-81. [PMID: 25516969 DOI: 10.1242/dev.109454] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Balancing stem cell self-renewal and initiation of lineage specification programs is essential for the development and homeostasis of the hematopoietic system. We have specifically ablated geminin in the developing murine hematopoietic system and observed profound defects in the generation of mature blood cells, leading to embryonic lethality. Hematopoietic stem cells (HSCs) accumulated in the fetal liver following geminin ablation, while committed progenitors were reduced. Genome-wide transcriptome analysis identified key HSC transcription factors as being upregulated upon geminin deletion, revealing a gene network linked with geminin that controls fetal hematopoiesis. In order to obtain mechanistic insight into the ability of geminin to regulate transcription, we examined Hoxa9 as an example of a key gene in definitive hematopoiesis. We demonstrate that in human K562 cells geminin is associated with HOXA9 regulatory elements and its absence increases HOXA9 transcription similarly to that observed in vivo. Moreover, silencing geminin reduced recruitment of the PRC2 component SUZ12 to the HOXA9 locus and resulted in an increase in RNA polymerase II recruitment and H3K4 trimethylation (H3K4me3), whereas the repressive marks H3K9me3 and H3K27me3 were reduced. The chromatin landscape was also modified at the regulatory regions of HOXA10 and GATA1. K562 cells showed a reduced ability to differentiate to erythrocytes and megakaryocytes upon geminin silencing. Our data suggest that geminin is indispensable for fetal hematopoiesis and regulates the generation of a physiological pool of stem and progenitor cells in the fetal hematopoietic system.
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Affiliation(s)
- Dimitris Karamitros
- Department of Physiology, Medical School, University of Patras, Rio, Patras 26504, Greece
| | - Alexandra L Patmanidi
- Department of Physiology, Medical School, University of Patras, Rio, Patras 26504, Greece
| | - Panoraia Kotantaki
- Department of Physiology, Medical School, University of Patras, Rio, Patras 26504, Greece
| | - Alexandre J Potocnik
- Division of Molecular Immunology, MRC/National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Tomi Bähr-Ivacevic
- European Molecular Biology Laboratory (EMBL), Core Facilities and Services, Meyerhofstraße 1, Heidelberg 69117, Germany
| | - Vladimir Benes
- European Molecular Biology Laboratory (EMBL), Core Facilities and Services, Meyerhofstraße 1, Heidelberg 69117, Germany
| | - Zoi Lygerou
- Department of Biology, Medical School, University of Patras, Rio, Patras 26504, Greece
| | - Dimitris Kioussis
- Division of Molecular Immunology, MRC/National Institute for Medical Research, The Ridgeway, London NW7 1AA, UK
| | - Stavros Taraviras
- Department of Physiology, Medical School, University of Patras, Rio, Patras 26504, Greece
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28
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Mehdipour P, Santoro F, Minucci S. Epigenetic alterations in acute myeloid leukemias. FEBS J 2014; 282:1786-800. [DOI: 10.1111/febs.13142] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 10/22/2014] [Accepted: 10/31/2014] [Indexed: 12/22/2022]
Affiliation(s)
- Parinaz Mehdipour
- Department of Experimental Oncology at the IFOM-IEO Campus; European Institute of Oncology; Milan Italy
| | - Fabio Santoro
- Department of Experimental Oncology at the IFOM-IEO Campus; European Institute of Oncology; Milan Italy
| | - Saverio Minucci
- Department of Experimental Oncology at the IFOM-IEO Campus; European Institute of Oncology; Milan Italy
- Department of Biosciences; University of Milan; Milan Italy
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29
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Ballabio E, Milne TA. Epigenetic control of gene expression in leukemogenesis: Cooperation between wild type MLL and MLL fusion proteins. Mol Cell Oncol 2014; 1:e955330. [PMID: 27308325 PMCID: PMC4905190 DOI: 10.1080/23723548.2014.955330] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Revised: 07/14/2014] [Accepted: 07/17/2014] [Indexed: 12/17/2022]
Abstract
Although there has been great progress in the treatment of human cancers, especially leukemias, many remain resistant to treatment. A major current focus is the development of so-called epigenetic drugs. Epigenetic states are stable enough to persist through multiple cell divisions, but by their very nature are reversible and thus are amenable to therapeutic manipulation. Exciting work in this area has produced a new breed of highly specific small molecules designed to inhibit epigenetic proteins, some of which have entered clinical trials. The current and future development of epigenetic drugs is greatly aided by highly detailed information about normal and aberrant epigenetic changes at the molecular level. In this review we focus on a class of aggressive acute leukemias caused by mutations in the Mixed Lineage Leukemia (MLL) gene. We provide an overview of how detailed molecular analysis of MLL leukemias has provided several early-stage epigenetic drugs and propose that further study of MLL leukemogenesis may continue to provide molecular details that potentially have a wider range of applications in human cancers.
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Affiliation(s)
- Erica Ballabio
- MRC Molecular Hematology Unit; Weatherall Institute of Molecular Medicine; University of Oxford ; Oxford, UK
| | - Thomas A Milne
- MRC Molecular Hematology Unit; Weatherall Institute of Molecular Medicine; University of Oxford ; Oxford, UK
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Messerschmidt DM, Knowles BB, Solter D. DNA methylation dynamics during epigenetic reprogramming in the germline and preimplantation embryos. Genes Dev 2014; 28:812-28. [PMID: 24736841 PMCID: PMC4003274 DOI: 10.1101/gad.234294.113] [Citation(s) in RCA: 446] [Impact Index Per Article: 44.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Methylation of DNA is an essential epigenetic control mechanism in mammals. Messerschmidt et al. review the current understanding of epigenetic dynamics regulating the molecular processes that prepare the mammalian embryo for normal development. Methylation of DNA is an essential epigenetic control mechanism in mammals. During embryonic development, cells are directed toward their future lineages, and DNA methylation poses a fundamental epigenetic barrier that guides and restricts differentiation and prevents regression into an undifferentiated state. DNA methylation also plays an important role in sex chromosome dosage compensation, the repression of retrotransposons that threaten genome integrity, the maintenance of genome stability, and the coordinated expression of imprinted genes. However, DNA methylation marks must be globally removed to allow for sexual reproduction and the adoption of the specialized, hypomethylated epigenome of the primordial germ cell and the preimplantation embryo. Recent technological advances in genome-wide DNA methylation analysis and the functional description of novel enzymatic DNA demethylation pathways have provided significant insights into the molecular processes that prepare the mammalian embryo for normal development.
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Affiliation(s)
- Daniel M Messerschmidt
- Developmental Epigenetics and Disease, Institute of Molecular and Cell Biology (IMCB), Agency for Science, Technology, and Research (A*STAR), 138673 Singapore,
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Fleischmann KK, Pagel P, Schmid I, Roscher AA. RNAi-mediated silencing of MLL-AF9 reveals leukemia-associated downstream targets and processes. Mol Cancer 2014; 13:27. [PMID: 24517546 PMCID: PMC3924703 DOI: 10.1186/1476-4598-13-27] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2013] [Accepted: 02/07/2014] [Indexed: 11/10/2022] Open
Abstract
Background The translocation t(9;11)(p22;q23) leading to the leukemogenic fusion gene MLL-AF9 is a frequent translocation in infant acute myeloid leukemia (AML). This study aimed to identify genes and molecular processes downstream of MLL-AF9 (alias MLL-MLLT3) which could assist to develop new targeted therapies for such leukemia with unfavorable prognosis. Methods In the AML cell line THP1 which harbors this t(9;11) translocation, endogenous MLL-AF9 was silenced via siRNA while ensuring specificity of the knockdown and its efficiency on functional protein level. Results The differential gene expression profile was validated for leukemia-association by gene set enrichment analysis of published gene sets from patient studies and MLL-AF9 overexpression studies and revealed 425 differentially expressed genes. Gene ontology analysis was consistent with a more differentiated state of MLL-AF9 depleted cells, with involvement of a wide range of downstream transcriptional regulators and with defined functional processes such as ribosomal biogenesis, chaperone binding, calcium homeostasis and estrogen response. We prioritized 41 gene products as candidate targets including several novel and potentially druggable effectors of MLL-AF9 (AHR, ATP2B2, DRD5, HIPK2, PARP8, ROR2 and TAS1R3). Applying the antagonist SCH39166 against the dopamine receptor DRD5 resulted in reduced leukemic cell characteristics of THP1 cells. Conclusion Besides potential new therapeutic targets, the described transcription profile shaped by MLL-AF9 provides an information source into the molecular processes altered in MLL aberrant leukemia.
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Affiliation(s)
- Katrin K Fleischmann
- Children's Research Center, Division of Pediatric Hematology and Oncology, Dr, von Hauner Children's Hospital, Ludwig-Maximilians-Universität München, Lindwurmstrasse 2a, München 80337, Germany.
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32
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Bina M, Wyss P, Novorolsky E, Zulkelfi N, Xue J, Price R, Fay M, Gutmann Z, Fogler B, Wang D. Discovery of MLL1 binding units, their localization to CpG Islands, and their potential function in mitotic chromatin. BMC Genomics 2013; 14:927. [PMID: 24373511 PMCID: PMC3890651 DOI: 10.1186/1471-2164-14-927] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2013] [Accepted: 12/16/2013] [Indexed: 11/10/2022] Open
Abstract
Background Mixed Lineage Leukemia 1 (MLL1) is a mammalian ortholog of the Drosophila Trithorax. In Drosophila, Trithorax complexes transmit the memory of active genes to daughter cells through interactions with Trithorax Response Elements (TREs). However, despite their functional importance, nothing is known about sequence features that may act as TREs in mammalian genomic DNA. Results By analyzing results of reported DNA binding assays, we identified several CpG rich motifs as potential MLL1 binding units (defined as morphemes). We find that these morphemes are dispersed within a relatively large collection of human promoter sequences and appear densely packed near transcription start sites of protein-coding genes. Genome wide analyses localized frequent morpheme occurrences to CpG islands. In the human HOX loci, the morphemes are spread across CpG islands and in some cases tail into the surrounding shores and shelves of the islands. By analyzing results of chromatin immunoprecipitation assays, we found a connection between morpheme occurrences, CpG islands, and chromatin segments reported to be associated with MLL1. Furthermore, we found a correspondence of reported MLL1-driven “bookmarked” regions in chromatin to frequent occurrences of MLL1 morphemes in CpG islands. Conclusion Our results implicate the MLL1 morphemes in sequence-features that define the mammalian TREs and provide a novel function for CpG islands. Apparently, our findings offer the first evidence for existence of potential TREs in mammalian genomic DNA and the first evidence for a connection between CpG islands and gene-bookmarking by MLL1 to transmit the memory of highly active genes during mitosis. Our results further suggest a role for overlapping morphemes in producing closely packed and multiple MLL1 binding events in genomic DNA so that MLL1 molecules could interact and reside simultaneously on extended potential transcriptional maintenance elements in human chromosomes to transmit the memory of highly active genes during mitosis.
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Affiliation(s)
- Minou Bina
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA.
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Ng RK, Kong CT, So CC, Lui WC, Chan YF, Leung KC, So KC, Tsang HM, Chan LC, Sham MH. Epigenetic dysregulation of leukaemic HOX code inMLL-rearranged leukaemia mouse model. J Pathol 2013; 232:65-74. [DOI: 10.1002/path.4279] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 09/19/2013] [Accepted: 09/22/2013] [Indexed: 01/13/2023]
Affiliation(s)
- Ray Kit Ng
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
- Centre for Reproduction, Development and Growth, Li Ka Shing Faculty of Medicine; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Cheuk Ting Kong
- Department of Biochemistry; University of Hong Kong, Pokfulam; Hong Kong SAR China
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
- Centre for Reproduction, Development and Growth, Li Ka Shing Faculty of Medicine; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Chi Chiu So
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
- Centre for Reproduction, Development and Growth, Li Ka Shing Faculty of Medicine; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Wing Chi Lui
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Yuen Fan Chan
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Ka Chun Leung
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Kam Chung So
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Ho Man Tsang
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Li Chong Chan
- SH Ho Foundation Research Laboratories, Department of Pathology, Hong Kong Jockey Club Clinical Research Centre; University of Hong Kong, Pokfulam; Hong Kong SAR China
- Centre for Reproduction, Development and Growth, Li Ka Shing Faculty of Medicine; University of Hong Kong, Pokfulam; Hong Kong SAR China
| | - Mai Har Sham
- Department of Biochemistry; University of Hong Kong, Pokfulam; Hong Kong SAR China
- Centre for Reproduction, Development and Growth, Li Ka Shing Faculty of Medicine; University of Hong Kong, Pokfulam; Hong Kong SAR China
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Jeong KW, Andreu-Vieyra C, You JS, Jones PA, Stallcup MR. Establishment of active chromatin structure at enhancer elements by mixed-lineage leukemia 1 to initiate estrogen-dependent gene expression. Nucleic Acids Res 2013; 42:2245-56. [PMID: 24288367 PMCID: PMC3936730 DOI: 10.1093/nar/gkt1236] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
A number of genome-wide analyses have revealed that estrogen receptor α binding to and regulation of its target genes correlate with binding of FOXA1, a pioneer factor, to nearby DNA sites in MCF-7 breast cancer cells. The enhancer element-specific histone H3K4me1/2 mark is enriched at the specific FOXA1/ERα recruitment sites in chromatin, but the mechanism by which these enhancer marks are established in chromatin before hormone treatment is unclear. Here, we show that mixed-lineage leukemia 1 (MLL1) protein is a key determinant that maintains permissive chromatin structure of the TFF1 enhancer region. MLL1 occupies the TFF1 enhancer region and methylates H3K4 before hormone stimulation. In vitro, MLL1 binds directly to the CpG-rich region of the TFF1 enhancer, and its binding is dependent on hypomethylation of DNA. Furthermore, the depletion of MLL1 in MCF-7 cells results in a dramatic decrease of chromatin accessibility and recruitment of FOXA1 and ERα to the enhancer element. Our study defines the mechanism by which MLL1 nucleates histone H3K4 methylation marks in CpG-enriched regions to maintain permissive chromatin architecture and allow FOXA1 and estrogen receptor α binding to transcriptional regulatory sites in breast cancer cells.
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Affiliation(s)
- Kwang Won Jeong
- Gachon Institute of Pharmaceutical Sciences, College of Pharmacy, Gachon University, Incheon 406-840, Republic of Korea, Departments of Urology and Biochemistry and Molecular Biology, USC Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089-9176, USA, Department of Biochemistry, School of Medicine, Konkuk University, Seoul 143-701, Republic of Korea and Department of Biochemistry and Molecular Biology, USC/Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089-9176, USA
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MicroRNA-regulated pathways in hematological malignancies: how to avoid cells playing out of tune. Int J Mol Sci 2013; 14:20930-53. [PMID: 24145746 PMCID: PMC3821651 DOI: 10.3390/ijms141020930] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2013] [Revised: 10/03/2013] [Accepted: 10/10/2013] [Indexed: 12/19/2022] Open
Abstract
The coordinated expression and interplay among lineage specific transcription factors and microRNAs contribute to the regulation of gene expression and determination of cell specificity. In hematopoietic stem cells (HSCs), unique combinations of transcription factors largely control growth and maturation of different blood cell lineages through cooperative regulation of specific target genes. MicroRNAs provide an additional level of control beyond transcription factors. By acting as regulators of crucial lineage-specific genetic programs, microRNAs direct early multipotential progenitor cells to adopt a certain cell fate program. Thus, alteration of specific microRNA levels may affect proliferation, differentiation and genetic stability of HSCs, contributing to the onset of myeloproliferative disorders and leukemia. The major aim of this review is to highlight the critical role of microRNA-regulated pathways during the establishment and progression of hematological malignancies, with a particular attention to leukemia, lymphomas and myelodysplastic syndromes. This will give us the opportunity to discuss the potential use of microRNA-based therapeutic approaches in these diseases. MicroRNAs are indeed emerging as relevant tools to improve the efficacy of currently used therapeutic protocols.
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Risner LE, Kuntimaddi A, Lokken AA, Achille NJ, Birch NW, Schoenfelt K, Bushweller JH, Zeleznik-Le NJ. Functional specificity of CpG DNA-binding CXXC domains in mixed lineage leukemia. J Biol Chem 2013; 288:29901-10. [PMID: 23990460 DOI: 10.1074/jbc.m113.474858] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The MLL CXXC domain binds nonmethylated CpG-containing DNA and is essential for the oncogenic properties of MLL fusion proteins. To determine potential functional promiscuity of similar DNA binding domains, we replaced the MLL CXXC domain in the context of the leukemogenic MLL-AF9 fusion with CXXC domains from DNMT1, CGBP (CFP1), and MBD1, or with a methyl-CpG-binding domain (MBD) from MBD1. MLL(DNMT1 CXXC)-AF9 shows robust in vitro colony forming activity and in vivo leukemogenesis, similar to MLL-AF9. However, colony forming ability and leukemogenicity are abrogated in MLL-AF9 containing either the CGBP or MBD1 CXXC domains or the MBD1 MBD domain. Direct comparison of in vitro DNA binding affinity of the isolated CXXC or MBD domains demonstrated that MLL, DNMT1, and CGBP CXXC domains could each bind to unmethylated DNA but with differing affinity. In contrast, the isolated MBD1 CXXC and MBD1 MBD domains were unable to bind to the same DNA. However, all substituted domains still allowed targeting of the MLL fusions to the functionally important Hoxa9 locus in primary bone marrow progenitor cells. In addition to DNA binding activity, it was critical that specific CpG residues in the Hoxa9 locus were protected from methylation for leukemia development. This ultimately prevented histone 3 lysine 9 trimethylation (H3K9me3) of the locus and enabled Hoxa9 expression. These were properties shared by MLL and DNMT1 CXXC domains but not by CGBP CXXC or the other swapped fusions tested. We demonstrate that similar CXXC domains can be mechanistically distinguished by specificity of CpG nucleotides preferentially protected from DNA methylation.
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Affiliation(s)
- Laurie E Risner
- From the Molecular Biology Program, Loyola University Medical Center, Maywood, Illinois 60153
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MLL fusion protein-driven AML is selectively inhibited by targeted disruption of the MLL-PAFc interaction. Blood 2013; 122:1914-22. [PMID: 23900238 DOI: 10.1182/blood-2013-02-486977] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
MLL rearrangements are common in leukemia and considered an adverse risk factor. Through interactions with the polymerase-associated factor complex (PAFc), mixed lineage leukemia (MLL) fusion proteins activate genes critical for blocking differentiation, such as HOXA9. Here we investigate whether the MLL-PAFc interaction can be exploited therapeutically using both genetic and biochemical approaches. We tested the genetic requirement of the PAFc in acute myeloid leukemia (AML) using a conditional allele of the PAFc subunit, Cdc73. We show that the PAFc is indiscriminately necessary for the proliferation of AML cells through the epigenetic regulation of proleukemogenic target genes, such as MEIS1 and Bcl2. To investigate the therapeutic potential of targeting the MLL-PAFc interaction, we engineered a dominant negative fragment of MLL capable of binding to the PAFc. Disruption of the MLL-PAFc interaction selectively inhibits the proliferation of MLL leukemic cells without affecting cells transformed by an unrelated E2A-HLF fusion protein. Using in vivo hematopoietic reconstitution assays, we demonstrate that disruption of the MLL-PAFc does not alter normal hematopoietic stem cell function. Together, our data show a selective growth inhibition of MLL-associated leukemic cells and tolerance of normal hematopoiesis to disruption of the MLL-PAFc interaction establishing the MLL-PAFc interaction as an attractive therapeutic target.
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Abstract
Advances in our understanding of the genetic determinants of leukemia have translated to better treatment options and improved survival of patients with acute myeloid and acute lymphoid leukemia. However, some leukemias, such as those bearing 11q23 (MLL) translocations, result in aggressive diseases with a relatively poor prognosis, despite improved treatments such as allogeneic hematopoietic stem cell transplantation. This article will briefly review the functions and regulation of wild-type MLL during normal hematopoiesis, while focusing on recent advances in our understanding of the molecular mechanisms governing MLL leukemias. The transcriptional targets, cooperating signaling pathways and molecular machinery involved in MLL-associated leukemias will be discussed, as well as how these may be harnessed for more personalized treatment of this disease.
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Affiliation(s)
- Andrew G Muntean
- Department of Pathology, Department of Medicine, University of Michigan Medical School, 7520B Medical Science Research Building I, 1301 Catherine Road, Ann Arbor, MI 48109-5602, USA
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Intrinsic and extrinsic connections of Tet3 dioxygenase with CXXC zinc finger modules. PLoS One 2013; 8:e62755. [PMID: 23690950 PMCID: PMC3653909 DOI: 10.1371/journal.pone.0062755] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 03/25/2013] [Indexed: 12/16/2022] Open
Abstract
Tet proteins are emerging as major epigenetic modulators of cell fate and plasticity. However, little is known about how Tet proteins are targeted to selected genomic loci in distinct biological contexts. Previously, a CXXC-type zinc finger domain in Tet1 was shown to bind CpG-rich DNA sequences. Interestingly, in human and mouse the Tet2 and Tet3 genes are adjacent to Cxxc4 and Cxxc10-1, respectively. The CXXC domains encoded by these loci, together with those in Tet1 and Cxxc5, identify a distinct homology group within the CXXC domain family. Here we provide evidence for alternative mouse Tet3 transcripts including the Cxxc10-1 sequence (Tet3CXXC) and for an interaction between Tet3 and Cxxc4. In vitro Cxxc4 and the isolated CXXC domains of Tet1 and Tet3CXXC bind DNA substrates with similar preference towards the modification state of cytosine at a single CpG site. In vivo Tet1 and Tet3 isoforms with and without CXXC domain hydroxylate genomic 5-methylcytosine with similar activity. Relative transcript levels suggest that distinct ratios of Tet3CXXC isoforms and Tet3-Cxxc4 complex may be present in adult tissues. Our data suggest that variable association with CXXC modules may contribute to context specific functions of Tet proteins.
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Osada T, Rydén AM, Masutani M. Poly(ADP-ribosylation) regulates chromatin organization through histone H3 modification and DNA methylation of the first cell cycle of mouse embryos. Biochem Biophys Res Commun 2013; 434:15-21. [PMID: 23548571 DOI: 10.1016/j.bbrc.2013.03.074] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Accepted: 03/24/2013] [Indexed: 10/27/2022]
Abstract
We examined the roles of poly(ADP-ribosylation) in chromatin remodeling during the first cell cycle of mouse embryos. Drug-based inhibition of poly(ADP-ribosylation) by a PARP inhibitor, PJ-34, revealed up-regulation of dimethylation of histone H3 at lysine 4 in male pronuclei and down-regulation of dimethylation of histone H3 at lysine 9 (H3K9) and lysine 27 (H3K27). Association of poly(ADP-ribosylation) with histone modification was suggested to be supported by the interaction of Suz12, a histone methyltransferase in the polycomb complex, with Parp1. PARP activity was suggested to be required for a proper localization and maintenance of Suz12 on chromosomes. Notably, DNA methylation level of female pronuclei in one-cell embryos was robustly decreased by PJ-34. Electron microscopic analysis showed a frequent appearance of unusual electron-dense areas within the female pronuclei, implying the disorganized and hypercondensed chromatin ultrastructure. These results show that poly(ADP-ribosylation) is important for the integrity of non-equivalent epigenetic dynamics of pronuclei during the first cell cycle of mouse embryos.
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Affiliation(s)
- Tomoharu Osada
- Advanced Medical Science Research Department, Mitsubishi Chemical Medience Corporation, 14-1 Sunayama, Kamisu-shi, Ibaragi 314-0255, Japan.
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Abstract
DNA methylation is among the best studied epigenetic modifications and is essential to mammalian development. Although the methylation status of most CpG dinucleotides in the genome is stably propagated through mitosis, improvements to methods for measuring methylation have identified numerous regions in which it is dynamically regulated. In this Review, we discuss key concepts in the function of DNA methylation in mammals, stemming from more than two decades of research, including many recent studies that have elucidated when and where DNA methylation has a regulatory role in the genome. We include insights from early development, embryonic stem cells and adult lineages, particularly haematopoiesis, to highlight the general features of this modification as it participates in both global and localized epigenetic regulation.
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Geng H, Brennan S, Milne TA, Chen WY, Li Y, Hurtz C, Kweon SM, Zickl L, Shojaee S, Neuberg D, Huang C, Biswas D, Xin Y, Racevskis J, Ketterling RP, Luger SM, Lazarus H, Tallman MS, Rowe JM, Litzow MR, Guzman ML, Allis CD, Roeder RG, Müschen M, Paietta E, Elemento O, Melnick AM. Integrative epigenomic analysis identifies biomarkers and therapeutic targets in adult B-acute lymphoblastic leukemia. Cancer Discov 2012; 2:1004-23. [PMID: 23107779 DOI: 10.1158/2159-8290.cd-12-0208] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
UNLABELLED Genetic lesions such as BCR-ABL1, E2A-PBX1, and MLL rearrangements (MLLr) are associated with unfavorable outcomes in adult B-cell precursor acute lymphoblastic leukemia (B-ALL). Leukemia oncoproteins may directly or indirectly disrupt cytosine methylation patterning to mediate the malignant phenotype. We postulated that DNA methylation signatures in these aggressive B-ALLs would point toward disease mechanisms and useful biomarkers and therapeutic targets. We therefore conducted DNA methylation and gene expression profiling on a cohort of 215 adult patients with B-ALL enrolled in a single phase III clinical trial (ECOG E2993) and normal control B cells. In BCR-ABL1-positive B-ALLs, aberrant cytosine methylation patterning centered around a cytokine network defined by hypomethylation and overexpression of IL2RA(CD25). The E2993 trial clinical data showed that CD25 expression was strongly associated with a poor outcome in patients with ALL regardless of BCR-ABL1 status, suggesting CD25 as a novel prognostic biomarker for risk stratification in B-ALLs. In E2A-PBX1-positive B-ALLs, aberrant DNA methylation patterning was strongly associated with direct fusion protein binding as shown by the E2A-PBX1 chromatin immunoprecipitation (ChIP) sequencing (ChIP-seq), suggesting that E2A-PBX1 fusion protein directly remodels the epigenome to impose an aggressive B-ALL phenotype. MLLr B-ALL featured prominent cytosine hypomethylation, which was linked with MLL fusion protein binding, H3K79 dimethylation, and transcriptional upregulation, affecting a set of known and newly identified MLL fusion direct targets with oncogenic activity such as FLT3 and BCL6. Notably, BCL6 blockade or loss of function suppressed proliferation and survival of MLLr leukemia cells, suggesting BCL6-targeted therapy as a new therapeutic strategy for MLLr B-ALLs. SIGNIFICANCE We conducted the first integrative epigenomic study in adult B-ALLs, as a correlative study to the ECOG E2993 phase III clinical trial. This study links for the first time the direct actions of oncogenic fusion proteins with disruption of epigenetic regulation mediated by cytosine methylation. We identify a novel clinically actionable biomarker in B-ALLs: IL2RA (CD25), which is linked with BCR-ABL1 and an inflammatory signaling network associated with chemotherapy resistance. We show that BCL6 is a novel MLL fusion protein target that is required to maintain the proliferation and survival of primary human adult MLLr cells and provide the basis for a clinical trial with BCL6 inhibitors for patients with MLLr.
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Affiliation(s)
- Huimin Geng
- Department of Medicine/Hematology-Oncology Division, Weill Medical College of Cornell University, New York, NY 10065, USA
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43
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Lee JW, Kim HS, Hwang J, Kim YH, Lim GY, Sohn WJ, Yoon SR, Kim JY, Park TS, Oh SH, Park KM, Choi SU, Ryoo ZY, Lee S. Regulation of HOXA9 activity by predominant expression of DACH1 against C/EBPα and GATA-1 in myeloid leukemia with MLL-AF9. Biochem Biophys Res Commun 2012; 426:299-305. [PMID: 22902925 DOI: 10.1016/j.bbrc.2012.08.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2012] [Accepted: 08/10/2012] [Indexed: 02/03/2023]
Abstract
Although MLL-AF9 caused by the chromosomal translocation t(9;11) has a critical role in acute myeloid leukemia, the molecular pathogenesis is poorly understood. Here, we identified that the cell fate determination factor DACH1 is directly up-regulated by MLL-AF9. Recently we showed that the forced expression of DACH1 in myeloid cells induced p27(Kip1) and repressed p21(Cip1), which is a pivotal characteristic of the myeloid progenitor. Consistent with our previous study, ectopic expression of DACH1 contributed to the maintenance of colonogenic activity and blocked the differentiation of myeloid progenitors. Moreover, we here identified an endogenous HOXA9-DACH1 complex mediated by the carboxyl terminus of DACH1 in t(9;11) leukemia cells. qRT-PCR revealed that DACH1 has a stronger transcription-promoting activity with HOXA9 than does PBX2 with HOXA9. Furthermore, C/EBPα and GATA-1 can directly bind to the promoter of DACH1 and act as a transcriptional suppressor. Expression of DACH1 is down-regulated during myeloid differentiation and shows an inverse pattern compared to C/EBPα and GATA-1 expression. However, ectopic expression of C/EBPα and/or GATA-1 could not abrogate the over-expression of DACH1 induced by MLL-AF9. Therefore, we postulate that the inability of C/EBPα and GATA-1 to down-regulate DACH1 expression induced by MLL-AF9 during myeloid differentiation may contribute to t(9;11) leukemogenesis.
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Affiliation(s)
- Jae-Woong Lee
- School of Life Science and Biotechnology, Kyungpook National University, Daegu 702-701, Republic of Korea
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Holmes T, Yan F, Ko KH, Nordon R, Song E, O'Brien TA, Dolnikov A. Ex vivo expansion of cord blood progenitors impairs their short-term and long-term repopulating activity associated with transcriptional dysregulation of signalling networks. Cell Prolif 2012; 45:266-78. [PMID: 22429797 DOI: 10.1111/j.1365-2184.2012.00813.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 01/13/2012] [Indexed: 01/18/2023] Open
Abstract
OBJECTIVES Cord blood (CB) has been established to be an alternative source of haematopoietic stem/progenitor cells (HPC) for transplantation. The number of HPC per CB unit is limited, which results in engraftment delay. Ex vivo expansion of HPC improvement must overcome this. MATERIALS AND METHODS Flow cytometry was used to extensively phenotype HPC pre- and post-expansion and CFDA-SE staining was used to track cell divisions. The NSG mouse model was employed in transplantation studies to determine long and short term repopulation in human cells. Gene array analysis was used to evaluate signalling pathways regulated following ex vivo expansion of HPC. RESULTS expansion of CD34(+) HPC impaired their regenerative function. In this xenograft transplantation model we showed that repopulating activity of CB cells declined following expansion. Expanded HPC had delayed engraftment at early and late stages post-transplant. High resolution division tracking revealed that the cultured HPC had reduced expansion and self-renewal probability and increased differentiation rate compared to non-expanded cells. Gene expression analysis exposed significant modulation of a complex network of genes and pathways that normally maintain HPC proliferation and limit their differentiation. CONCLUSIONS The decline in short-term engraftment is consistent with the loss of rapid SCID repopulating ability r(SRA) by expanded CD34(+) CD38(+) cells recently reported. Our data raise concerns for future clinical applications of expanded HPC alone in transplantation.
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Affiliation(s)
- T Holmes
- Sydney Cord & Marrow Transplant Facility, Sydney Children's Hospital, Sydney, NSW, Australia
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45
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Li Z, Huang H, Chen P, He M, Li Y, Arnovitz S, Jiang X, He C, Hyjek E, Zhang J, Zhang Z, Elkahloun A, Cao D, Shen C, Wunderlich M, Wang Y, Neilly MB, Jin J, Wei M, Lu J, Valk PJM, Delwel R, Lowenberg B, Le Beau MM, Vardiman J, Mulloy JC, Zeleznik-Le NJ, Liu PP, Zhang J, Chen J. miR-196b directly targets both HOXA9/MEIS1 oncogenes and FAS tumour suppressor in MLL-rearranged leukaemia. Nat Commun 2012; 3:688. [PMID: 22353710 PMCID: PMC3514459 DOI: 10.1038/ncomms1681] [Citation(s) in RCA: 125] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Accepted: 01/11/2012] [Indexed: 01/07/2023] Open
Abstract
HOXA9 and MEIS1 have essential oncogenic roles in mixed lineage leukaemia (MLL)-rearranged leukaemia. Here we show that they are direct targets of miRNA-196b, a microRNA (miRNA) located adjacent to and co-expressed with HOXA9, in MLL-rearranged leukaemic cells. Forced expression of miR-196b significantly delays MLL-fusion-mediated leukemogenesis in primary bone marrow transplantation through suppressing Hoxa9/Meis1 expression. However, ectopic expression of miR-196b results in more aggressive leukaemic phenotypes and causes much faster leukemogenesis in secondary transplantation than MLL fusion alone, likely through the further repression of Fas expression, a proapoptotic gene downregulated in MLL-rearranged leukaemia. Overexpression of FAS significantly inhibits leukemogenesis and reverses miR-196b-mediated phenotypes. Targeting Hoxa9/Meis1 and Fas by miR-196b is probably also important for normal haematopoiesis. Thus, our results uncover a previously unappreciated miRNA-regulation mechanism by which a single miRNA may target both oncogenes and tumour suppressors, simultaneously, or, sequentially, in tumourigenesis and normal development per cell differentiation, indicating that miRNA regulation is much more complex than previously thought.
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Affiliation(s)
- Zejuan Li
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Hao Huang
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Ping Chen
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Miao He
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA.,Department of Pharmacology, China Medical University, Shenyang, 110001, Liaoning, China
| | - Yuanyuan Li
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Stephen Arnovitz
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Xi Jiang
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Chunjiang He
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Elizabeth Hyjek
- Department of Pathology, University of Chicago, Chicago, 60637, Illinois, USA
| | - Jun Zhang
- Oncology Institute, Cardinal Bernardin Cancer Center, Loyola University Medical Center, Maywood, 60153, Illinois, USA
| | - Zhiyu Zhang
- Tang Center for Herbal Medicine Research, University of Chicago, Chicago, 60637, Illinois, USA
| | - Abdel Elkahloun
- Genetics and Molecular Biology Branch, National Human Genome Research Institute, NIH, Bethesda, 20892, Maryland, USA
| | - Donglin Cao
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA.,Department of Laboratory Medicine, Guangdong No.2 Provincial People's Hospital, Guangzhou, 510317, Guangdong, China
| | - Chen Shen
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Mark Wunderlich
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, 45229, Ohio, USA
| | - Yungui Wang
- Institute of Hematology, the First Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, 310058, Zhejiang, China
| | - Mary Beth Neilly
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - Jie Jin
- Institute of Hematology, the First Affiliated Hospital, Zhejiang University College of Medicine, Hangzhou, 310058, Zhejiang, China
| | - Minjie Wei
- Department of Pharmacology, China Medical University, Shenyang, 110001, Liaoning, China
| | - Jun Lu
- Department of Genetics, Yale Stem Cell Center, Yale University, New Haven, 06520, Connecticut, USA
| | - Peter J M Valk
- Department of Hematology, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands
| | - Ruud Delwel
- Department of Hematology, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands
| | - Bob Lowenberg
- Department of Hematology, Erasmus University Medical Center, 3000 CA Rotterdam, The Netherlands
| | - Michelle M Le Beau
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA
| | - James Vardiman
- Department of Pathology, University of Chicago, Chicago, 60637, Illinois, USA
| | - James C Mulloy
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, 45229, Ohio, USA
| | - Nancy J Zeleznik-Le
- Department of Medicine, Loyola University Medical Center, Maywood, 60153, Illinois, USA
| | - Paul P Liu
- Genetics and Molecular Biology Branch, National Human Genome Research Institute, NIH, Bethesda, 20892, Maryland, USA
| | - Jiwang Zhang
- Oncology Institute, Cardinal Bernardin Cancer Center, Loyola University Medical Center, Maywood, 60153, Illinois, USA
| | - Jianjun Chen
- Department of Medicine, University of Chicago, Chicago, 60637, Illinois, USA.
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46
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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: 253] [Impact Index Per Article: 19.5] [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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47
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Abstract
The past decade has highlighted the central role of epigenetic processes in cancer causation, progression and treatment. Next-generation sequencing is providing a window for visualizing the human epigenome and how it is altered in cancer. This view provides many surprises, including linking epigenetic abnormalities to mutations in genes that control DNA methylation, the packaging and the function of DNA in chromatin, and metabolism. Epigenetic alterations are leading candidates for the development of specific markers for cancer detection, diagnosis and prognosis. The enzymatic processes that control the epigenome present new opportunities for deriving therapeutic strategies designed to reverse transcriptional abnormalities that are inherent to the cancer epigenome.
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Affiliation(s)
- Stephen B. Baylin
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, Baltimore, Maryland 21231, USA
| | - Peter A. Jones
- The USC Norris Comprehensive Cancer Center, Keck School of Medicine, University of Southern California, Los Angeles, California 90089, USA
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Laursen KB, Wong PM, Gudas LJ. Epigenetic regulation by RARα maintains ligand-independent transcriptional activity. Nucleic Acids Res 2011; 40:102-15. [PMID: 21911359 PMCID: PMC3245912 DOI: 10.1093/nar/gkr637] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Retinoic acid receptors (RARs) α, β and γ are key regulators of embryonic development. Hematopoietic differentiation is regulated by RARα, and several types of leukemia show aberrant RARα activity. Through microarray expression analysis, we identified transcripts differentially expressed between F9 wild-type (Wt) and RARα knockout cells cultured in the absence or presence of the RAR-specific ligand all trans retinoic acid (RA). We validated the decreased Mest, Tex13, Gab1, Bcl11a, Tcfap2a and HMGcs1 transcript levels, and increased Slc38a4, Stmn2, RpL39l, Ref2L, Mobp and Rlf1 transcript levels in the RARa knockout cells. The decreased Mest and Tex13 transcript levels were associated with increased promoter CpG-island methylation and increased repressive histone modifications (H3K9me3) in RARα knockout cells. Increased Slc38a4 and Stmn2 transcript levels were associated with decreased promoter CpG-island methylation and increased permissive histone modifications (H3K9/K14ac, H3K4me3) in RARα knockout cells. We demonstrated specific association of RARα and RXRα with the Mest promoter. Importantly, stable expression of a dominant negative, oncogenic PML–RARα fusion protein in F9 Wt cells recapitulated the decreased Mest transcript levels observed in RARα knockout cells. We propose that RARα plays an important role in cellular memory and imprinting by regulating the CpG methylation status of specific promoter regions.
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Affiliation(s)
- Kristian B Laursen
- Pharmacology Department of Weill Cornell Medical College of Cornell University, NY 10065, USA
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49
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Tao Y, Liu S, Briones V, Geiman TM, Muegge K. Treatment of breast cancer cells with DNA demethylating agents leads to a release of Pol II stalling at genes with DNA-hypermethylated regions upstream of TSS. Nucleic Acids Res 2011; 39:9508-20. [PMID: 21880597 PMCID: PMC3239205 DOI: 10.1093/nar/gkr611] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Inactivation of tumor suppressor genes plays an important role in tumorigenesis, and epigenetic modifications such as DNA methylation are frequently associated with transcriptional repression. Here, we show that gene silencing at selected genes with signs of DNA hypermethylation in breast cancer cells involves Pol II stalling. We studied several repressed genes with DNA hypermethylation within a region 1-kb upstream of the transcriptional start site that were upregulated after treatment with DNA demethylating agents, such as Azacytidine and several natural products. All those selected genes had stalled Pol II at their transcriptional start site and showed enhanced ser2 phosphorylated Pol II and elevated transcripts after drug treatment indicating successful elongation. In addition, a decrease of the epigenetic regulator LSH in a breast cancer cell line by siRNA treatment reduced DNA methylation and overcame Pol II stalling, whereas overexpression of LSH in a normal breast epithelial cell line increased DNA methylation and resulted in repression. Decrease of LSH was associated with reduced DNMT3b binding to promoter sequences, and depletion of DNMT3b by siRNA could release Pol II suggesting that DNMT3b is functionally involved. The release of paused Pol II was accompanied by a dynamic switch from repressive to active chromatin marks. Thus release of Pol II stalling can act as a mechanism for gene reactivation at specific target genes after DNA demethylating treatment in cancer cells.
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Affiliation(s)
- Yongguang Tao
- Laboratory of Cancer Prevention, SAIC-Frederick, National Cancer Institute, Frederick, Maryland 21701, USA
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50
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Methylation-mediated repression of microRNA-143 enhances MLL-AF4 oncogene expression. Oncogene 2011; 31:507-17. [PMID: 21706045 DOI: 10.1038/onc.2011.248] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Fusion proteins containing the amino terminus of mixed lineage leukemia (MLL) are common in acute lymphoblastic leukemia (ALL) due to translocations. The MLL-AF4 fusion protein is generated by the translocation t(4;11)(q21;q23), and t(4;11)-positive ALL patients (MLL-AF4 ALL), have a notoriously poorer prognosis compared with patients with other MLL-associated leukemias. The detailed role of this fusion protein in leukemogenesis is not well understood. MicroRNAs (miRNAs) targeting the AF4 3' untranslated regions may modulate MLL-AF4 fusion protein levels, raising the question of whether regulation of these miRNAs are involved in the progression of MLL-AF4 ALL. In this study, we show that miR-143 was identified as a regulator of MLL-AF4 expression in MLL-AF4 ALL samples. Restoration of miR-143 in MLL-AF4-positive RS4;11 and MV4-11 cells induced apoptosis, negatively contributing to leukemia cell growth by reducing MLL-AF4 fusion protein levels. Furthermore, miR-143 was epigenetically repressed by promoter hypermethylation in MLL-AF4-positive primary blasts and cell lines, but not in normal bone marrow cells and MLL-AF4-negative primary blasts, which was directly associated with expression of the MLL-AF4 oncogene. This is the first study to show that miR-143 functions as a tumor suppressor in MLL-AF4 B-cell ALL. These data reveal the therapeutic promise of upregulating miR-143 expression for MLL-AF4 B-cell ALL.
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