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Ueda K, Ikeda K. Cellular carcinogenesis in preleukemic conditions:drivers and defenses. Fukushima J Med Sci 2024; 70:11-24. [PMID: 37952978 PMCID: PMC10867434 DOI: 10.5387/fms.2023-17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Accepted: 09/26/2023] [Indexed: 11/14/2023] Open
Abstract
Acute myeloid leukemia (AML) arises from preleukemic conditions. We have investigated the pathogenesis of typical preleukemia, myeloproliferative neoplasms, and clonal hematopoiesis. Hematopoietic stem cells in both preleukemic conditions harbor recurrent driver mutations; additional mutation provokes further malignant transformation, leading to AML onset. Although genetic alterations are defined as the main cause of malignant transformation, non-genetic factors are also involved in disease progression. In this review, we focus on a non-histone chromatin protein, high mobility group AT-hook2 (HMGA2), and a physiological p53 inhibitor, murine double minute X (MDMX). HMGA2 is mainly overexpressed by dysregulation of microRNAs or mutations in polycomb components, and provokes expansion of preleukemic clones through stem cell signature disruption. MDMX is overexpressed by altered splicing balance in myeloid malignancies. MDMX induces leukemic transformation from preleukemia via suppression of p53 and p53-independent activation of WNT/β-catenin signaling. We also discuss how these non-genetic factors can be targeted for leukemia prevention therapy.
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Affiliation(s)
- Koki Ueda
- Department of Blood Transfusion and Transplantation Immunology, Fukushima Medical University
| | - Kazuhiko Ikeda
- Department of Blood Transfusion and Transplantation Immunology, Fukushima Medical University
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2
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Insufficiency of non-canonical PRC1 synergizes with JAK2V617F in the development of myelofibrosis. Leukemia 2021; 36:452-463. [PMID: 34497325 DOI: 10.1038/s41375-021-01402-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 08/19/2021] [Accepted: 08/26/2021] [Indexed: 12/22/2022]
Abstract
Insufficiency of polycomb repressive complex 2 (PRC2), which trimethylates histone H3 at lysine 27, is frequently found in primary myelofibrosis and promotes the development of JAK2V617F-induced myelofibrosis in mice by enhancing the production of dysplastic megakaryocytes. Polycomb group ring finger protein 1 (Pcgf1) is a component of PRC1.1, a non-canonical PRC1 that monoubiquitylates H2A at lysine 119 (H2AK119ub1). We herein investigated the impact of PRC1.1 insufficiency on myelofibrosis. The deletion of Pcgf1 in JAK2V617F mice strongly promoted the development of lethal myelofibrosis accompanied by a block in erythroid differentiation. Transcriptome and chromatin immunoprecipitation sequence analyses showed the de-repression of PRC1.1 target genes in Pcgf1-deficient JAK2V617F hematopoietic progenitors and revealed Hoxa cluster genes as direct targets. The deletion of Pcgf1 in JAK2V617F hematopoietic stem and progenitor cells (HSPCs), as well as the overexpression of Hoxa9, restored the attenuated proliferation of JAK2V617F progenitors. The overexpression of Hoxa9 also enhanced JAK2V617F-mediated myelofibrosis. The expression of PRC2 target genes identified in PRC2-insufficient JAK2V617F HSPCs was not largely altered in Pcgf1-deleted JAK2V617F HSPCs. The present results revealed a tumor suppressor function for PRC1.1 in myelofibrosis and suggest that PRC1.1 insufficiency has a different impact from that of PRC2 insufficiency on the pathogenesis of myelofibrosis.
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Dutta A, Nath D, Yang Y, Le BT, Mohi G. CDK6 Is a Therapeutic Target in Myelofibrosis. Cancer Res 2021; 81:4332-4345. [PMID: 34145036 PMCID: PMC8373692 DOI: 10.1158/0008-5472.can-21-0590] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 05/05/2021] [Accepted: 06/16/2021] [Indexed: 12/14/2022]
Abstract
Myelofibrosis (myelofibrosis) is a deadly blood neoplasia with the worst prognosis among myeloproliferative neoplasms (MPN). The JAK2 inhibitors ruxolitinib and fedratinib have been approved for treatment of myelofibrosis, but they do not offer significant improvement of bone marrow fibrosis. CDK6 expression is significantly elevated in MPN/myelofibrosis hematopoietic progenitor cells. In this study, we investigated the efficacy of CDK4/6 inhibitor palbociclib alone or in combination with ruxolitinib in Jak2V617F and MPLW515L murine models of myelofibrosis. Treatment with palbociclib alone significantly reduced leukocytosis and splenomegaly and inhibited bone marrow fibrosis in Jak2V617F and MPLW515L mouse models of myelofibrosis. Combined treatment of palbociclib and ruxolitinib resulted in normalization of peripheral blood leukocyte counts, marked reduction of spleen size, and abrogation of bone marrow fibrosis in murine models of myelofibrosis. Palbociclib treatment also preferentially inhibited Jak2V617F mutant hematopoietic progenitors in mice. Mechanistically, treatment with palbociclib or depletion of CDK6 inhibited Aurora kinase, NF-κB, and TGFβ signaling pathways in Jak2V617F mutant hematopoietic cells and attenuated expression of fibrotic markers in the bone marrow. Overall, these data suggest that palbociclib in combination with ruxolitinib may have therapeutic potential for treatment of myelofibrosis and support the clinical investigation of this drug combination in patients with myelofibrosis. SIGNIFICANCE: These findings demonstrate that CDK6 inhibitor palbociclib in combination with ruxolitinib ameliorates myelofibrosis, suggesting this drug combination could be an effective therapeutic strategy against this devastating blood disorder.
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Affiliation(s)
- Avik Dutta
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Dipmoy Nath
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Yue Yang
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Bao T. Le
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Golam Mohi
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA,University of Virginia Cancer Center, Charlottesville, VA 22908, USA
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Yokokawa T, Misaka T, Kimishima Y, Wada K, Minakawa K, Sugimoto K, Ishida T, Morishita S, Komatsu N, Ikeda K, Takeishi Y. Crucial role of hematopoietic JAK2 V617F in the development of aortic aneurysms. Haematologica 2021; 106:1910-1922. [PMID: 33567809 PMCID: PMC8252954 DOI: 10.3324/haematol.2020.264085] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Indexed: 12/11/2022] Open
Abstract
JAK2 V617F is the most frequent driver mutation in myeloproliferative neoplasms (MPN) and is associated with vascular complications. However, the impact of hematopoietic JAK2 V617F on aortic aneurysms (AA) remains unknown. Our cross-sectional study indicated that nine (23%) of 39 MPN patients with JAK2 V617F exhibited the presence of AA. In order to clarify whether the hematopoietic JAK2 V617F contributes to the AA, we applied bone marrow transplantation (BMT) with the donor cells from Jak2 V617F transgenic (JAK2V617F) mice or control wild-type (WT) mice into lethally irradiated apolipoprotein E-deficient mice. Five weeks after BMT, the JAK2V617F-BMT mice and WT-BMT mice were subjected to continuous angiotensin II infusion to induce AA formation. Four weeks after angiotensin II infusion, the abdominal aorta diameter in the JAK2V617F-BMT mice was significantly enlarged compared to that in the WT-BMT mice. Additionally, the abdominal AA-free survival rate was significantly lower in the JAK2V617F-BMT mice. Hematopoietic JAK2 V617F accelerated aortic elastic lamina degradation as well as activation of matrix metalloproteinase (MMP)-2 and MMP-9 in the abdominal aorta. The numbers of infiltrated macrophages were significantly upregulated in the abdominal aorta of the JAK2V617F-BMT mice accompanied by STAT3 phosphorylation. The accumulation of BM-derived hematopoietic cells carrying JAK2 V617F in the abdominal aorta was confirmed by use of the reporter green fluorescent proteintransgene. BM-derived macrophages carrying JAK2 V617F showed increases in mRNA expression levels of Mmp2, Mmp9, and Mmp13. Ruxolitinib decreased the abdominal aorta diameter and the incidence of abdominal AA in the JAK2V617F-BMT mice. Our findings provide a novel feature of vascular complications of AA in MPN with JAK2 V617F.
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Affiliation(s)
- Tetsuro Yokokawa
- Department of Cardiovascular Medicine, Fukushima Medical University, Fukushima, Japan; Department of Pulmonary Hypertension, Fukushima Medical University, Fukushima
| | - Tomofumi Misaka
- Department of Cardiovascular Medicine, Fukushima Medical University, Fukushima, Japan; Department of Advanced Cardiac Therapeutics, Fukushima Medical University, Fukushima.
| | - Yusuke Kimishima
- Department of Cardiovascular Medicine, Fukushima Medical University, Fukushima
| | - Kento Wada
- Department of Cardiovascular Medicine, Fukushima Medical University, Fukushima
| | - Keiji Minakawa
- Department of Blood Transfusion and Transplantation Immunology, Fukushima Medical University, Fukushima
| | - Koichi Sugimoto
- Department of Cardiovascular Medicine, Fukushima Medical University, Fukushima, Japan; Department of Pulmonary Hypertension, Fukushima Medical University, Fukushima
| | - Takafumi Ishida
- Department of Cardiovascular Medicine, Fukushima Medical University, Fukushima
| | - Soji Morishita
- Department of Transfusion Medicine and Stem Cell Regulation, Juntendo University Graduate School of Medicine, Tokyo
| | - Norio Komatsu
- Department of Hematology, Juntendo University Graduate School of Medicine, Tokyo
| | - Kazuhiko Ikeda
- Department of Blood Transfusion and Transplantation Immunology, Fukushima Medical University, Fukushima.
| | - Yasuchika Takeishi
- Department of Cardiovascular Medicine, Fukushima Medical University, Fukushima
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Pegoraro S, Ros G, Sgubin M, Petrosino S, Zambelli A, Sgarra R, Manfioletti G. Targeting the intrinsically disordered architectural High Mobility Group A (HMGA) oncoproteins in breast cancer: learning from the past to design future strategies. Expert Opin Ther Targets 2020; 24:953-969. [PMID: 32970506 DOI: 10.1080/14728222.2020.1814738] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Triple-negative breast cancer (TNBC) is the most difficult breast cancer subtype to treat because of its heterogeneity and lack of specific therapeutic targets. High Mobility Group A (HMGA) proteins are chromatin architectural factors that have multiple oncogenic functions in breast cancer, and they represent promising molecular therapeutic targets for this disease. AREAS COVERED We offer an overview of the strategies that have been exploited to counteract HMGA oncoprotein activities at the transcriptional and post-transcriptional levels. We also present the possibility of targeting cancer-associated factors that lie downstream of HMGA proteins and discuss the contribution of HMGA proteins to chemoresistance. EXPERT OPINION Different strategies have been exploited to counteract HMGA protein activities; these involve interfering with their nucleic acid binding properties and the blocking of HMGA expression. Some approaches have provided promising results. However, some unique characteristics of the HMGA proteins have not been exploited; these include their extensive protein-protein interaction network and their intrinsically disordered status that present the possibility that HMGA proteins could be involved in the formation of proteinaceous membrane-less organelles (PMLO) by liquid-liquid phase separation. These unexplored characteristics could open new pharmacological avenues to counteract the oncogenic contributions of HMGA proteins.
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Affiliation(s)
- Silvia Pegoraro
- Department of Life Sciences, University of Trieste , Trieste, Italy
| | - Gloria Ros
- Department of Life Sciences, University of Trieste , Trieste, Italy
| | - Michela Sgubin
- Department of Life Sciences, University of Trieste , Trieste, Italy
| | - Sara Petrosino
- Department of Life Sciences, University of Trieste , Trieste, Italy
| | | | - Riccardo Sgarra
- Department of Life Sciences, University of Trieste , Trieste, Italy
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Jacquelin S, Kramer F, Mullally A, Lane SW. Murine Models of Myelofibrosis. Cancers (Basel) 2020; 12:cancers12092381. [PMID: 32842500 PMCID: PMC7563264 DOI: 10.3390/cancers12092381] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Revised: 08/17/2020] [Accepted: 08/18/2020] [Indexed: 01/22/2023] Open
Abstract
Myelofibrosis (MF) is subtype of myeloproliferative neoplasm (MPN) characterized by a relatively poor prognosis in patients. Understanding the factors that drive MF pathogenesis is crucial to identifying novel therapeutic approaches with the potential to improve patient care. Driver mutations in three main genes (janus kinase 2 (JAK2), calreticulin (CALR), and myeloproliferative leukemia virus oncogene (MPL)) are recurrently mutated in MPN and are sufficient to engender MPN using animal models. Interestingly, animal studies have shown that the underlying molecular mutation and the acquisition of additional genetic lesions is associated with MF outcome and transition from early stage MPN such as essential thrombocythemia (ET) and polycythemia vera (PV) to secondary MF. In this issue, we review murine models that have contributed to a better characterization of MF pathobiology and identification of new therapeutic opportunities in MPN.
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Affiliation(s)
- Sebastien Jacquelin
- Cancer program QIMR Berghofer Medical Research Institute, Brisbane, Queensland 4006, Australia
- Correspondence: (S.J.); (S.W.L.)
| | - Frederike Kramer
- Division of Hematology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (F.K.); (A.M.)
| | - Ann Mullally
- Division of Hematology, Department of Medicine, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA; (F.K.); (A.M.)
| | - Steven W. Lane
- Cancer program QIMR Berghofer Medical Research Institute, Brisbane, Queensland 4006, Australia
- Cancer Care Services, The Royal Brisbane and Women’s Hospital, Brisbane 4029, Australia
- University of Queensland, St Lucia, QLD 4072, Australia
- Correspondence: (S.J.); (S.W.L.)
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Minervini A, Coccaro N, Anelli L, Zagaria A, Specchia G, Albano F. HMGA Proteins in Hematological Malignancies. Cancers (Basel) 2020; 12:cancers12061456. [PMID: 32503270 PMCID: PMC7353061 DOI: 10.3390/cancers12061456] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Revised: 05/25/2020] [Accepted: 06/01/2020] [Indexed: 02/07/2023] Open
Abstract
The high mobility group AT-Hook (HMGA) proteins are a family of nonhistone chromatin remodeling proteins known as "architectural transcriptional factors". By binding the minor groove of AT-rich DNA sequences, they interact with the transcription apparatus, altering the chromatin modeling and regulating gene expression by either enhancing or suppressing the binding of the more usual transcriptional activators and repressors, although they do not themselves have any transcriptional activity. Their involvement in both benign and malignant neoplasias is well-known and supported by a large volume of studies. In this review, we focus on the role of the HMGA proteins in hematological malignancies, exploring the mechanisms through which they enhance neoplastic transformation and how this knowledge could be exploited to devise tailored therapeutic strategies.
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Affiliation(s)
| | | | | | | | | | - Francesco Albano
- Correspondence: ; Tel.: +39-(0)80-5478031; Fax: +39-(0)80-5508369
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Schieber M, Crispino JD, Stein B. Myelofibrosis in 2019: moving beyond JAK2 inhibition. Blood Cancer J 2019; 9:74. [PMID: 31511492 PMCID: PMC6739355 DOI: 10.1038/s41408-019-0236-2] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/26/2019] [Accepted: 03/15/2019] [Indexed: 02/08/2023] Open
Abstract
Myelofibrosis (MF) is a myeloproliferative neoplasm characterized by ineffective clonal hematopoiesis, splenomegaly, bone marrow fibrosis, and the propensity for transformation to acute myeloid leukemia. The discovery of mutations in JAK2, CALR, and MPL have uncovered activated JAK-STAT signaling as a primary driver of MF, supporting a rationale for JAK inhibition. However, JAK inhibition alone is insufficient for long-term remission and offers modest, if any, disease-modifying effects. Given this, there is great interest in identifying mechanisms that cooperate with JAK-STAT signaling to predict disease progression and rationally guide the development of novel therapies. This review outlines the latest discoveries in the biology of MF, discusses current clinical management of patients with MF, and summarizes the ongoing clinical trials that hope to change the landscape of MF treatment.
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Affiliation(s)
- Michael Schieber
- Robert H. Lurie Comprehensive Cancer Center, Division of Hematology/Oncology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - John D Crispino
- Robert H. Lurie Comprehensive Cancer Center, Division of Hematology/Oncology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA
| | - Brady Stein
- Robert H. Lurie Comprehensive Cancer Center, Division of Hematology/Oncology, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL, USA.
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Yang J, Liu C, Jihang Z, Yu J, Dai L, Ding X, Qiu Y, Yu S, Yang Y, Wu Y, Huang L. PPARA genetic variants increase the risk for cardiac pumping function reductions following acute high-altitude exposure: A self-controlled study. Mol Genet Genomic Med 2019; 7:e00919. [PMID: 31407515 PMCID: PMC6785441 DOI: 10.1002/mgg3.919] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2019] [Revised: 07/22/2019] [Accepted: 07/23/2019] [Indexed: 12/22/2022] Open
Abstract
Background Left cardiac pumping function determines the compensatory capacity of the cardiovascular system following acute high‐altitude exposure. Variations in cardiac output (CO) at high altitude are inconsistent between individuals, and genetic susceptibility may play a crucial role. We sought to identify genetic causes of cardiac pumping function variations and describe the genotype–phenotype correlations. Methods A total of 151 young male volunteers were recruited and transferred to Lhasa (3,700 m) from Chengdu (<500 m) by plane. Genetic information related to hypoxic signaling and cardiovascular‐related pathways was collected before departure. Echocardiography was performed both before departure and 24 hr after arrival at high altitude. Results Here we reported that PPARA variants were closely related to high‐altitude cardiac function. The variants of rs6520015 C‐allele and rs7292407 A‐allele significantly increased the risk for cardiac pumping function reductions following acute high‐altitude exposure. In addition, the individuals carrying haplotypes in PPARA, namely, rs135538 C‐allele, rs4253623 A‐allele, rs6520015 C‐allele and rs7292407 A‐allele (C‐A‐C‐A), suffered a 7.27‐fold risk for cardiac pumping function reduction (95% CI: 2.39–22.15, p = .0006) compared with those carrying the wild‐type haplotype. Conclusions This self‐controlled study revealed that PPARA variations significantly increased the risk for cardiac pumping function reductions following acute high‐altitude exposure, providing a potential predictive marker before high‐altitude exposure and targets in mechanistic studies.
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Affiliation(s)
- Jie Yang
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Chuan Liu
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Zhang Jihang
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Jie Yu
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Limeng Dai
- Department of Medical Genetics, College of Basic Medical Science, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Xiaohan Ding
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Youzhu Qiu
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Sanjiu Yu
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Yuanqi Yang
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Yuzhang Wu
- Institute of Immunology, Army Medical University (Third Military Medical University), Chongqing, PR China
| | - Lan Huang
- Department of Cardiology, the Second Affiliated Hospital, Army Medical University (Third Military Medical University), Chongqing, PR China
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Rontauroli S, Norfo R, Pennucci V, Zini R, Ruberti S, Bianchi E, Salati S, Prudente Z, Rossi C, Rosti V, Guglielmelli P, Barosi G, Vannucchi A, Tagliafico E, Manfredini R. miR-494-3p overexpression promotes megakaryocytopoiesis in primary myelofibrosis hematopoietic stem/progenitor cells by targeting SOCS6. Oncotarget 2017; 8:21380-21397. [PMID: 28423484 PMCID: PMC5400591 DOI: 10.18632/oncotarget.15226] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 01/23/2017] [Indexed: 11/25/2022] Open
Abstract
Primary myelofibrosis (PMF) is a chronic Philadelphia-negative myeloproliferative neoplasm characterized by hematopoietic stem cell-derived clonal myeloproliferation, involving especially the megakaryocyte lineage. To better characterize how the altered expression of microRNAs might contribute to PMF pathogenesis, we have previously performed the integrative analysis of gene and microRNA expression profiles of PMF hematopoietic stem/progenitor cells (HSPCs), which allowed us to identify miR-494-3p as the upregulated microRNA predicted to target the highest number of downregulated mRNAs.To elucidate the role of miR-494-3p in hematopoietic differentiation, in the present study we demonstrated that miR-494-3p enforced expression in normal HSPCs promotes megakaryocytopoiesis. Gene expression profiling upon miR-494-3p overexpression allowed the identification of genes commonly downregulated both after microRNA overexpression and in PMF CD34+ cells. Among them, suppressor of cytokine signaling 6 (SOCS6) was confirmed to be a miR-494-3p target by luciferase assay. Western blot analysis showed reduced level of SOCS6 protein as well as STAT3 activation in miR-494-3p overexpressing cells. Furthermore, transient inhibition of SOCS6 expression in HSPCs demonstrated that SOCS6 silencing stimulates megakaryocytopoiesis, mimicking the phenotypic effects observed upon miR-494-3p overexpression. Finally, to disclose the contribution of miR-494-3p upregulation to PMF pathogenesis, we performed inhibition experiments in PMF HSPCs, which showed that miR-494-3p silencing led to SOCS6 upregulation and impaired megakaryocyte differentiation.Taken together, our results describe for the first time the role of miR-494-3p during normal HSPC differentiation and suggest that its increased expression, and the subsequent downregulation of its target SOCS6, might contribute to the megakaryocyte hyperplasia commonly observed in PMF patients.
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Affiliation(s)
- Sebastiano Rontauroli
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Ruggiero Norfo
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Valentina Pennucci
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Roberta Zini
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Samantha Ruberti
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Elisa Bianchi
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Simona Salati
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Zelia Prudente
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Chiara Rossi
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
| | - Vittorio Rosti
- Center for The Study of Myelofibrosis, Biotechnology Research Area, IRCCS Policlinico S. Matteo Foundation, Pavia, Italy
| | - Paola Guglielmelli
- CRIMM-Center for Research and Innovation for Myeloproliferative Neoplasms, AOU Careggi, and Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Giovanni Barosi
- Center for The Study of Myelofibrosis, Biotechnology Research Area, IRCCS Policlinico S. Matteo Foundation, Pavia, Italy
| | - Alessandro Vannucchi
- CRIMM-Center for Research and Innovation for Myeloproliferative Neoplasms, AOU Careggi, and Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Enrico Tagliafico
- Center for Genome Research, University of Modena and Reggio Emilia, Modena, Italy
| | - Rossella Manfredini
- Centre for Regenerative Medicine, Life Sciences Department, University of Modena and Reggio Emilia, Modena, Italy
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Hmga2 promotes the development of myelofibrosis in Jak2 V617F knockin mice by enhancing TGF-β1 and Cxcl12 pathways. Blood 2017. [PMID: 28637665 DOI: 10.1182/blood-2016-12-757344] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Myelofibrosis (MF) is a devastating blood disorder. The JAK2V617F mutation has been detected in ∼50% cases of MF. Elevated expression of high-mobility group AT hook 2 (HMGA2) has also been frequently observed in patients with MF. Interestingly, upregulation of HMGA2 expression has been found in association with the JAK2V617F mutation in significant cases of MF. However, the contribution of HMGA2 in the pathogenesis of MF remains elusive. To determine the effects of concurrent expression of HMGA2 and JAK2V617F mutation in hematopoiesis, we transduced bone marrow cells from Jak2V617F knockin mice with lentivirus expressing Hmga2 and performed bone marrow transplantation. Expression of Hmga2 enhanced megakaryopoiesis, increased extramedullary hematopoiesis, and accelerated the development of MF in mice expressing Jak2V617F Mechanistically, the data show that expression of Hmga2 enhances the activation of transforming growth factor-β1 (TGF-β1) and Cxcl12 pathways in mice expressing Jak2V617F In addition, expression of Hmga2 causes upregulation of Fzd2, Ifi27l2a, and TGF-β receptor 2. Forced expression of Cxcl12, Fzd2, or Ifi27l2a increases megakaryocytic differentiation and proliferation in the bone marrow of Jak2V617F mice, whereas TGF-β1 or Cxcl12 stimulation induces collagen deposition in the bone marrow mesenchymal stromal cells. Together, these findings demonstrate that expression of Hmga2 cooperates with Jak2V617F in the pathogenesis of MF.
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12
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Hmga2 collaborates with JAK2V617F in the development of myeloproliferative neoplasms. Blood Adv 2017; 1:1001-1015. [PMID: 29296743 DOI: 10.1182/bloodadvances.2017004457] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 05/18/2017] [Indexed: 12/13/2022] Open
Abstract
High-mobility group AT-hook 2 (HMGA2) is crucial for the self-renewal of fetal hematopoietic stem cells (HSCs) but is downregulated in adult HSCs via repression by MIRlet-7 and the polycomb-recessive complex 2 (PRC2) including EZH2. The HMGA2 messenger RNA (mRNA) level is often elevated in patients with myelofibrosis that exhibits an advanced myeloproliferative neoplasm (MPN) subtype, and deletion of Ezh2 promotes the progression of severe myelofibrosis in JAK2V617F mice with upregulation of several oncogenes such as Hmga2. However, the direct role of HMGA2 in the pathogenesis of MPNs remains unknown. To clarify the impact of HMGA2 on MPNs carrying the driver mutation, we generated ΔHmga2/JAK2V617F mice overexpressing Hmga2 due to deletion of the 3' untranslated region. Compared with JAK2V617F mice, ΔHmga2/JAK2V617F mice exhibited more severe leukocytosis, anemia and splenomegaly, and shortened survival, whereas severity of myelofibrosis was comparable. ΔHmga2/JAK2V617F cells showed a greater repopulating ability that reproduced the severe MPN compared with JAK2V617F cells in serial bone marrow transplants, indicating that Hmga2 promotes MPN progression at the HSC level. Hmga2 also enhanced apoptosis of JAK2V617F erythroblasts that may worsen anemia. Relative to JAK2V617F hematopoietic stem and progenitor cells (HSPCs), over 30% of genes upregulated in ΔHmga2/JAK2V617F HSPCs overlapped with those derepressed by Ezh2 loss in JAK2V617F/Ezh2Δ/Δ HSPCs, suggesting that Hmga2 may facilitate upregulation of Ezh2 targets. Correspondingly, deletion of Hmga2 ameliorated anemia and splenomegaly in JAK2V617F/Ezh2Δ/wild-type mice, and MIRlet-7 suppression and PRC2 mutations correlated with the elevated HMGA2 mRNA levels in patients with MPNs, especially myelofibrosis. These findings suggest the crucial role of HMGA2 in MPN progression.
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13
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Furukawa M, Ohkawara H, Ogawa K, Ikeda K, Ueda K, Shichishima-Nakamura A, Ito E, Imai JI, Yanagisawa Y, Honma R, Watanabe S, Waguri S, Ikezoe T, Takeishi Y. Autocrine and Paracrine Interactions between Multiple Myeloma Cells and Bone Marrow Stromal Cells by Growth Arrest-specific Gene 6 Cross-talk with Interleukin-6. J Biol Chem 2017; 292:4280-4292. [PMID: 28154173 DOI: 10.1074/jbc.m116.733030] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 01/19/2017] [Indexed: 12/12/2022] Open
Abstract
The pathogenesis of multiple myeloma (MM) has not yet been fully elucidated. Our microarray analysis and immunohistochemistry revealed significant up-regulation of growth arrest-specific gene 6 (Gas6), a vitamin K-dependent protein with a structural homology with protein S, in bone marrow (BM) cells of MM patients. ELISA showed that the serum levels of soluble Gas6 were significantly increased in the MM patients when compared with healthy controls. Gas6 was overexpressed in the human CD138-positive MM cell line RPMI-8226. Exogenous Gas6 suppressed apoptosis induced by serum deprivation and enhanced cell proliferation of the MM cells. The conditional medium from the human BM stromal cell line HS-5 induced cell proliferation and anti-apoptosis of the MM cells with extracellular signal-regulated kinase, Akt, and nuclear factor-κB phosphorylation, which were reversed by the neutralizing antibody to Gas6 or IL-6. The TAM family receptor Mer, which has been identified as a Gas6 receptor, was overexpressed in BM cells of MM patients. The knockdown of Mer by siRNA inhibited cell proliferation, anti-apoptosis, and up-regulation of intercellular cell adhesion molecule-1 (ICAM-1) in MM cells stimulated by an HS-5 cell-conditioned medium. Furthermore, the Gas6-neutralizing antibody reduced the up-regulation of IL-6 and ICAM-1 induced by a HS-5 cell-conditioned medium in MM cells. The present study provides new evidence that autocrine and paracrine stimulation of Gas6 in concert with IL-6 contributes to the pathogenesis of MM, suggesting that Gas6-Mer-related signaling pathways may be a promising novel target for treating MM.
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Affiliation(s)
| | | | | | - Kazuhiko Ikeda
- From the Departments of Hematology.,Blood Transfusion and Transplantation Immunology, and
| | | | | | - Emi Ito
- the Translational Research Center, Fukushima Medical University, Fukushima 960-1295 and
| | - Jun-Ichi Imai
- the Translational Research Center, Fukushima Medical University, Fukushima 960-1295 and
| | - Yuka Yanagisawa
- the Translational Research Center, Fukushima Medical University, Fukushima 960-1295 and
| | | | - Shinya Watanabe
- the Translational Research Center, Fukushima Medical University, Fukushima 960-1295 and
| | - Satoshi Waguri
- the Translational Research Center, Fukushima Medical University, Fukushima 960-1295 and
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14
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Chen CC, You JY, Lung J, Huang CE, Chen YY, Leu YW, Ho HY, Li CP, Lu CH, Lee KD, Hsu CC, Gau JP. Aberrant let7a/HMGA2 signaling activity with unique clinical phenotype in JAK2-mutated myeloproliferative neoplasms. Haematologica 2017; 102:509-518. [PMID: 28057739 PMCID: PMC5394969 DOI: 10.3324/haematol.2016.154385] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Accepted: 12/30/2016] [Indexed: 02/02/2023] Open
Abstract
High mobility group AT-hook 2 (HMGA2) is an architectural transcription factor that is negatively regulated by let-7 microRNA through binding to it’s 3′-untranslated region. Transgenic mice expressing Hmga2 with a truncation of its 3′-untranslated region has been shown to exhibit a myeloproliferative phenotype. To decipher the let-7-HMGA2 axis in myeloproliferative neoplasms, we employed an in vitro model supplemented with clinical correlation. Ba/F3 cells with inducible JAK2V617F expression (Ton.JAK2.V617F cells) showed upregulation of HMGA2 with concurrent let-7a repression. Ton.JAK2.V617F cells treated with a let-7a inhibitor exhibited further escalation of Hmga2 expression, while a let-7a mimic diminished the Hmga2 transcript level. Hmga2 overexpression conferred JAK2-mutated cells with a survival advantage through inhibited apoptosis. A pan-JAK inhibitor, INC424, increased the expression of let-7a, downregulated the level of Hmga2, and led to increased apoptosis in Ton.JAK2.V617F cells in a dose-dependent manner. In samples from 151 patients with myeloproliferative neoplasms, there was a modest inverse correlation between the expression levels of let-7a and HMGA2. Overexpression of HMGA2 was detected in 29 (19.2%) of the cases, and it was more commonly seen in patients with essential thrombocythemia than in those with polycythemia vera (26.9% vs. 12.7%, P=0.044). Patients with upregulated HMGA2 showed an increased propensity for developing major thrombotic events, and they were more likely to harbor one of the 3 driver myeloproliferative neoplasm mutations in JAK2, MPL and CALR. Our findings suggest that, in a subset of myeloproliferative neoplasm patients, the let-7-HMGA2 axis plays a prominent role in the pathogenesis of the disease that leads to unique clinical phenotypes.
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Affiliation(s)
- Chih-Cheng Chen
- Division of Hematology and Oncology, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan.,College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Jie-Yu You
- Division of Hematology and Oncology, Department of Medicine, Lotung Poh-Ai Hospital, Yilan, Taiwan.,School of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Jrhau Lung
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Cih-En Huang
- Division of Hematology and Oncology, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan.,College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Yi-Yang Chen
- Division of Hematology and Oncology, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Yu-Wei Leu
- Department of Life Science and Institute of Molecular Biology, National Chung Cheng University, Chiayi, Taiwan
| | - Hsing-Ying Ho
- Division of Hematology and Oncology, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Chian-Pei Li
- Division of Hematology and Oncology, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Chang-Hsien Lu
- Division of Hematology and Oncology, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan.,College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Kuan-Der Lee
- Division of Hematology and Oncology, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan.,College of Medicine, Chang Gung University, Tao-Yuan, Taiwan
| | - Chia-Chen Hsu
- Division of Hematology and Oncology, Department of Medicine, Chang Gung Memorial Hospital, Chiayi, Taiwan
| | - Jyh-Pyng Gau
- School of Medicine, National Yang-Ming University, Taipei, Taiwan .,Division of Hematology, Department of Medicine, Taipei Veterans General Hospital, Taiwan
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15
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Ikeda K, Ueda K, Sano T, Ogawa K, Ikezoe T, Hashimoto Y, Morishita S, Komatsu N, Ohto H, Takeishi Y. The Amelioration of Myelofibrosis with Thrombocytopenia by a JAK1/2 Inhibitor, Ruxolitinib, in a Post-polycythemia Vera Myelofibrosis Patient with a JAK2 Exon 12 Mutation. Intern Med 2017; 56:1705-1710. [PMID: 28674362 PMCID: PMC5519475 DOI: 10.2169/internalmedicine.56.7871] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Less than 5% of patients with polycythemia vera (PV) show JAK2 exon 12 mutations. Although PV patients with JAK2 exon 12 mutations are known to develop post-PV myelofibrosis (MF) as well as PV with JAK2V617F, the role of JAK inhibitors in post-PV MF patients with JAK2 exon 12 mutations remains unknown. We describe how treatment with a JAK1/2 inhibitor, ruxolitinib, led to the rapid amelioration of marrow fibrosis, erythrocytosis and thrombocytopenia in a 77-year-old man with post-PV MF who carried a JAK2 exon 12 mutation (JAK2H538QK539L). This case suggests that ruxolitinib is a treatment option for post-PV MF in patients with thrombocytopenia or JAK2 exon 12 mutations.
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Affiliation(s)
- Kazuhiko Ikeda
- Department of Hematology, Fukushima Medical University, Japan
- Department of Transfusion and Transplantation Immunology, Fukushima Medical University, Japan
| | - Koki Ueda
- Department of Hematology, Fukushima Medical University, Japan
| | - Takahiro Sano
- Department of Hematology, Fukushima Medical University, Japan
| | - Kazuei Ogawa
- Department of Hematology, Fukushima Medical University, Japan
| | - Takayuki Ikezoe
- Department of Hematology, Fukushima Medical University, Japan
| | - Yuko Hashimoto
- Department of Pathology and Diagnostic Pathology, Fukushima Medical University, Japan
| | - Soji Morishita
- Department of Transfusion Medicine and Stem Cell Regulation, Juntendo University Graduate School of Medicine, Japan
| | - Norio Komatsu
- Department of Hematology, Juntendo University School of Medicine, Japan
| | - Hitoshi Ohto
- Department of Transfusion and Transplantation Immunology, Fukushima Medical University, Japan
| | - Yasuchika Takeishi
- Department of Cardiovascular Medicine, Fukushima Medical University, Japan
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16
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Sashida G, Wang C, Tomioka T, Oshima M, Aoyama K, Kanai A, Mochizuki-Kashio M, Harada H, Shimoda K, Iwama A. The loss of Ezh2 drives the pathogenesis of myelofibrosis and sensitizes tumor-initiating cells to bromodomain inhibition. J Exp Med 2016; 213:1459-77. [PMID: 27401345 PMCID: PMC4986523 DOI: 10.1084/jem.20151121] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 04/29/2016] [Indexed: 12/12/2022] Open
Abstract
Loss of Ezh2 in the presence of activating mutation in JAK2 (JAK2V617F) cooperatively alters transcriptional programs of hematopoiesis, activates specific oncogenes, and promotes the development of myelofibrosis. EZH2 is a component of polycomb repressive complex 2 (PRC2) and functions as an H3K27 methyltransferase. Loss-of-function mutations in EZH2 are associated with poorer outcomes in patients with myeloproliferative neoplasms (MPNs), particularly those with primary myelofibrosis (MF [PMF]). To determine how EZH2 insufficiency is involved in the pathogenesis of PMF, we generated mice compound for an Ezh2 conditional deletion and activating mutation in JAK2 (JAK2V617F) present in patients with PMF. The deletion of Ezh2 in JAK2V617F mice markedly promoted the development of MF, indicating a tumor suppressor function for EZH2 in PMF. The loss of Ezh2 in JAK2V617F hematopoietic cells caused significant reductions in H3K27 trimethylation (H3K27me3) levels, resulting in an epigenetic switch to H3K27 acetylation (H3K27ac). These epigenetic switches were closely associated with the activation of PRC2 target genes including Hmga2, an oncogene implicated in the pathogenesis of PMF. The treatment of JAK2V617F/Ezh2-null mice with a bromodomain inhibitor significantly attenuated H3K27ac levels at the promoter regions of PRC2 targets and down-regulated their expression, leading to the abrogation of MF-initiating cells. Therefore, an EZH2 insufficiency not only cooperated with active JAK2 to induce MF, but also conferred an oncogenic addiction to the H3K27ac modification in MF-initiating cells that was capable of being restored by bromodomain inhibition.
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Affiliation(s)
- Goro Sashida
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan International Research Center for Medical Sciences, Kumamoto University, Chuo-ku, Kumamoto 860-0811, Japan
| | - Changshan Wang
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan College of Life Sciences, Inner Mongolia University, Hohhot 010021, China
| | - Takahisa Tomioka
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan
| | - Motohiko Oshima
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan
| | - Kazumasa Aoyama
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan
| | - Akinori Kanai
- Department of Molecular Oncology and Leukemia Program Project, Research Institute for Radiation Biology and Medicine, Hiroshima University, Minami-ku, Hiroshima 734-8553, Japan
| | - Makiko Mochizuki-Kashio
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan
| | - Hironori Harada
- Department of Hematology, Juntendo University School of Medicine, Bunkyo-ku, Tokyo 113-8421, Japan
| | - Kazuya Shimoda
- Department of Gastroenterology and Hematology, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan
| | - Atsushi Iwama
- Department of Cellular and Molecular Medicine, Graduate School of Medicine, Chiba University, Chuo-ku, Chiba 260-8670, Japan
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17
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Oshima M, Hasegawa N, Mochizuki-Kashio M, Muto T, Miyagi S, Koide S, Yabata S, Wendt GR, Saraya A, Wang C, Shimoda K, Suzuki Y, Iwama A. Ezh2 regulates the Lin28/let-7 pathway to restrict activation of fetal gene signature in adult hematopoietic stem cells. Exp Hematol 2016; 44:282-96.e3. [DOI: 10.1016/j.exphem.2015.12.009] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Revised: 12/29/2015] [Accepted: 12/30/2015] [Indexed: 11/16/2022]
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18
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Wu Z, Eguchi-Ishimae M, Yagi C, Iwabuki H, Gao W, Tauchi H, Inukai T, Sugita K, Ishii E, Eguchi M. HMGA2 as a potential molecular target in KMT2A-AFF1-positive infant acute lymphoblastic leukaemia. Br J Haematol 2015; 171:818-29. [PMID: 26403224 DOI: 10.1111/bjh.13763] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Accepted: 07/29/2015] [Indexed: 12/30/2022]
Abstract
Acute lymphoblastic leukaemia (ALL) in infants is an intractable cancer in childhood. Although recent intensive chemotherapy progress has considerably improved ALL treatment outcome, disease cure is often accompanied by undesirable long-term side effects, and efficient, less toxic molecular targeting therapies have been anticipated. In infant ALL cells with KMT2A (MLL) fusion, the microRNA let-7b (MIRLET7B) is significantly downregulated by DNA hypermethylation of its promoter region. We show here that the expression of HMGA2, one of the oncogenes repressed by MIRLET7B, is reversely upregulated in infant ALL leukaemic cells, particularly in KMT2A-AFF1 (MLL-AF4) positive ALL. In addition to the suppression of MIRLET7B, KMT2A fusion proteins positively regulate the expression of HMGA2. HMGA2 is one of the negative regulators of CDKN2A gene, which encodes the cyclin-dependent kinase inhibitor p16(INK4A) . The HMGA2 inhibitor netropsin, when combined with demethylating agent 5-azacytidine, upregulated and sustained the expression of CDKN2A, which resulted in growth suppression of KMT2A-AFF1-expressing cell lines. This effect was more apparent compared to treatment with 5-azacytidine alone. These results indicate that the MIRLET7B-HMGA2-CDKN2A axis plays an important role in cell proliferation of leukaemic cells and could be a possible molecular target for the therapy of infant ALL with KMT2A-AFF1.
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Affiliation(s)
- Zhouying Wu
- Department of Paediatrics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
| | | | - Chihiro Yagi
- Department of Paediatrics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
| | - Hidehiko Iwabuki
- Department of Paediatrics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
| | - Wenming Gao
- Department of Paediatrics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
| | - Hisamichi Tauchi
- Department of Paediatrics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
| | - Takeshi Inukai
- Department of Paediatrics, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Kanji Sugita
- Department of Paediatrics, University of Yamanashi, Chuo, Yamanashi, Japan
| | - Eiichi Ishii
- Department of Paediatrics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
| | - Mariko Eguchi
- Department of Paediatrics, Ehime University Graduate School of Medicine, Toon, Ehime, Japan
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Barosi G. Setting Appropriate Goals for the Next Generation of Clinical Trials in Myelofibrosis. Curr Hematol Malig Rep 2015; 10:362-9. [PMID: 26277615 DOI: 10.1007/s11899-015-0281-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
New targeted therapies administered in phase II and phase III studies have produced substantial improvements in outcomes of myelofibrosis (MF). However, strong documentation that the new agents modify the natural history of the disease is lacking, and a number of therapeutic indications of new drugs remain unaddressed. Overall survival (OS) improvement is the major goal of next-generation clinical trials in MF. This may be attained if an adequate population of patients and an unambiguous design of the trial will be selected. Another goal is preventing disease progression in early MF: this requires a controlled clinical trial with an accessible endpoint and a clinically relevant definition of disease progression. Improvement in the documentation of responsiveness of patient-reported outcomes (PROs) will allow to use them as a critical endpoint of new trials. Finally, exploiting the clinical utility of biomarkers should become a major goal of future clinical experimentation in MF.
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Affiliation(s)
- Giovanni Barosi
- Center for the Study of Myelofibrosis, Biotechnology Research Area, IRCCS Policlinico S. Matteo Foundation, Viale Golgi 19, 27100, Pavia, Italy.
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