1
|
Deutsch JL, Heath JL. MLLT10 in benign and malignant hematopoiesis. Exp Hematol 2020; 87:1-12. [PMID: 32569758 DOI: 10.1016/j.exphem.2020.06.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 06/16/2020] [Accepted: 06/18/2020] [Indexed: 01/01/2023]
Abstract
Non-random chromosomal translocations involving the putative transcription factor Mixed Lineage Leukemia Translocated to 10 (MLLT10, also known as AF10) are commonly observed in both acute myeloid and lymphoid leukemias and are indicative of a poor prognosis. Despite the well-described actions of oncogenic MLLT10 fusion proteins, the role of wild-type MLLT10 in hematopoiesis is not well characterized. The protein structure and several interacting partners have been described and provide indications as to the potential functions of MLLT10. This review examines these aspects of MLLT10, contextualizing its function in benign and malignant hematopoiesis.
Collapse
Affiliation(s)
- Jamie L Deutsch
- Department of Pediatrics, University of Vermont, Burlington, VT
| | - Jessica L Heath
- Department of Pediatrics, University of Vermont, Burlington, VT; Department of Biochemistry, University of Vermont, Burlington, VT 05405; University of Vermont Cancer Center, Burlington, VT.
| |
Collapse
|
2
|
Ehm P, Nalaskowski MM, Wundenberg T, Jücker M. The tumor suppressor SHIP1 colocalizes in nucleolar cavities with p53 and components of PML nuclear bodies. Nucleus 2015; 6:154-64. [PMID: 25723258 DOI: 10.1080/19491034.2015.1022701] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The inositol 5-phosphatase SHIP1 is a negative regulator of signaling processes in haematopoietic cells. By converting PI(3,4,5)P3 to PtdIns(3,4)P2 at the plasma membrane, SHIP1 modifies PI3-kinase mediated signaling. We have recently demonstrated that SHIP1 is a nucleo-cytoplasmic shuttling protein and SHIP1 nuclear puncta partially colocalize with FLASH, a component of nuclear bodies. In this study, we demonstrate that endogenous SHIP1 localizes to intranucleolar regions of both normal and leukemic haematopoietic cells. In addition, we report that ectopically expressed SHIP1 accumulates in nucleolar cavities and colocalizes with the tumor suppressor protein p53 and components of PML nuclear bodies (e.g. SP100, SUMO-1 and CK2). Moreover, SHIP1 also colocalizes in nucleolar cavities with components of the ubiquitin-proteasome pathway. By using confocal microscopy data, we generated 3D-models revealing the enormous extent of the SHIP1 aggresomes in the nucleolus. Furthermore, treatment of cells with the proteasome inhibitor MG132 causes an enlargement of nucleolar SHIP1 containing structures. Unexpectedly, this accumulation can be partially prevented by treatment with the inhibitor of nuclear protein export Leptomycin B. In recent years, several proteins aggregating in nucleolar cavities were shown to be key factors of neurodegenerative diseases and cancerogenesis. Our findings support current relevance of nuclear localized SHIP1.
Collapse
Key Words
- DFC, dense fibrillar component
- DIC, Differential interference contrast
- EGFP, enhanced green fluorescent protein
- FC, fibrillar center
- GC, granular component
- LMB, leptomycin B
- MG132
- NES, nuclear export signal
- PBMC, Peripheral Blood Mononuclear Cell
- PML bodies
- PML, Promyelocytic Leukemia
- PtdIns(3, 4)P2, phosphatidylinositol-(3, 4)-bisphosphate
- PtdIns(3, 4, 5)P3, phosphatidylinositol-(3, 4, 5)-trisphosphate
- RNA pol, RNA polymerase
- SHIP1
- SHIP1, src homology 2 domain-containing inositol phosphatase 1
- UPP, ubiquitin-proteasome pathway.
- aggresome
- cancer
- leptomycin B
- nucleolar cavities
- nucleus
- p53
- ubiquitin proteasome pathway
Collapse
Affiliation(s)
- Patrick Ehm
- a Institute of Biochemistry and Signal Transduction ; University Medical Center Hamburg-Eppendorf ; Hamburg , Germany
| | | | | | | |
Collapse
|
3
|
Deshpande AJ, Deshpande A, Sinha AU, Chen L, Chang J, Cihan A, Fazio M, Chen CW, Zhu N, Koche R, Dzhekieva L, Ibáñez G, Dias S, Banka D, Krivtsov A, Luo M, Roeder RG, Bradner JE, Bernt KM, Armstrong SA. AF10 regulates progressive H3K79 methylation and HOX gene expression in diverse AML subtypes. Cancer Cell 2014; 26:896-908. [PMID: 25464900 PMCID: PMC4291116 DOI: 10.1016/j.ccell.2014.10.009] [Citation(s) in RCA: 129] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 07/14/2014] [Accepted: 10/16/2014] [Indexed: 12/13/2022]
Abstract
Homeotic (HOX) genes are dysregulated in multiple malignancies, including several AML subtypes. We demonstrate that H3K79 dimethylation (H3K79me2) is converted to monomethylation (H3K79me1) at HOX loci as hematopoietic cells mature, thus coinciding with a decrease in HOX gene expression. We show that H3K79 methyltransferase activity as well as H3K79me1-to-H3K79me2 conversion is regulated by the DOT1L cofactor AF10. AF10 inactivation reverses leukemia-associated epigenetic profiles, precludes abnormal HOXA gene expression, and impairs the transforming ability of MLL-AF9, MLL-AF6, and NUP98-NSD1 fusions-mechanistically distinct HOX-activating oncogenes. Furthermore, NUP98-NSD1-transformed cells are sensitive to small-molecule inhibition of DOT1L. Our findings demonstrate that pharmacological inhibition of the DOT1L/AF10 complex may provide therapeutic benefits in an array of malignancies with abnormal HOXA gene expression.
Collapse
Affiliation(s)
- Aniruddha J Deshpande
- Division of Hematology/Oncology, Children's Hospital Boston, Boston, MA 02115, USA; Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Anagha Deshpande
- Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Amit U Sinha
- Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Liying Chen
- Division of Hematology/Oncology, Children's Hospital Boston, Boston, MA 02115, USA
| | - Jenny Chang
- Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Ali Cihan
- Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, NY 10065, USA
| | - Maurizio Fazio
- Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Chun-Wei Chen
- Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Nan Zhu
- Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Richard Koche
- Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Liuda Dzhekieva
- Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Gloria Ibáñez
- Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Stuart Dias
- Division of Hematology/Oncology, Children's Hospital Boston, Boston, MA 02115, USA
| | - Deepti Banka
- Division of Hematology/Oncology, Children's Hospital Boston, Boston, MA 02115, USA
| | - Andrei Krivtsov
- Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Minkui Luo
- Molecular Pharmacology and Chemistry Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Robert G Roeder
- Laboratory of Biochemistry and Molecular Biology, The Rockefeller University, New York, NY 10065, USA
| | - James E Bradner
- Department of Medical Oncology, Dana Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA
| | - Kathrin M Bernt
- Department of Pediatrics, University of Colorado Anshutz Medical Campus, Aurora, CO 80045 USA
| | - Scott A Armstrong
- Division of Hematology/Oncology, Children's Hospital Boston, Boston, MA 02115, USA; Department of Pediatrics and the Human Oncology and Pathogenesis Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
| |
Collapse
|