1
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Wei Z, Su L, Gao S. The roles of ubiquitination in AML. Ann Hematol 2024; 103:3413-3428. [PMID: 37603061 DOI: 10.1007/s00277-023-05415-y] [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: 04/25/2023] [Accepted: 08/10/2023] [Indexed: 08/22/2023]
Abstract
Acute myeloid leukemia (AML) is a heterogeneously malignant disorder resulting in poor prognosis. Ubiquitination, a major post-translational modification (PTM), plays an essential role in regulating various cellular processes and determining cell fate. Despite these initial insights, the precise role of ubiquitination in AML pathogenesis and treatment remains largely unknown. In order to address this knowledge gap, we explore the relationship between ubiquitination and AML from the perspectives of signal transduction, cell differentiation, and cell cycle control; and try to find out how this relationship can be utilized to inform new therapeutic strategies for AML patients.
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Affiliation(s)
- Zhifeng Wei
- Department of Hematology, The First Hospital of Jilin University, Changchun, China
| | - Long Su
- Department of Hematology, The First Hospital of Jilin University, Changchun, China
| | - Sujun Gao
- Department of Hematology, The First Hospital of Jilin University, Changchun, China.
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2
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Paredes de la Fuente R, Sucre S, Ponce C, Rattani AAA, Peters MLB. Somatic Mutation Profile as a Predictor of Treatment Response and Survival in Unresectable Pancreatic Ductal Adenocarcinoma Treated with FOLFIRINOX and Gemcitabine Nab-Paclitaxel. Cancers (Basel) 2024; 16:2734. [PMID: 39123462 PMCID: PMC11312283 DOI: 10.3390/cancers16152734] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2024] [Revised: 07/25/2024] [Accepted: 07/29/2024] [Indexed: 08/12/2024] Open
Abstract
(1) Background: Pancreatic ductal adenocarcinoma (PDAC) has low survival rates despite treatment advancements. Aim: This study aims to show how molecular profiling could possibly guide personalized treatment strategies, which may help improve survival outcomes in patients with PDAC. (2) Materials and Methods: A retrospective analysis of 142 PDAC patients from a single academic center was conducted. Patients underwent chemotherapy and next-generation sequencing for molecular profiling. Key oncogenic pathways were identified using the Reactome pathway database. Survival analysis was performed using Kaplan-Meier curves and Cox Proportional Hazards Regression. (3) Results: Patients mainly received FOLFIRINOX (n = 62) or gemcitabine nab-paclitaxel (n = 62) as initial chemotherapy. The median OS was 13.6 months. Longer median OS was noted in patients with NOTCH (15 vs. 12.3 months, p = 0.007) and KIT pathway mutations (21.3 vs. 12.12 months, p = 0.04). Combinatorial pathway analysis indicated potential synergistic effects on survival. In the PFS, PI3K pathway (6.6 vs. 5.7 months, p = 0.03) and KIT pathway (10.3 vs. 6.2 months, p = 0.03) mutations correlated with improved PFS within the gemcitabine nab-paclitaxel subgroup. (4) Conclusions: Molecular profiling could play a role in PDAC for predicting outcomes and responses to therapies like FOLFIRINOX and gemcitabine nab-paclitaxel. Integrating genomic data into clinical decision-making can benefit PDAC treatment, though further validation is needed to fully utilize precision oncology in PDAC management.
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Affiliation(s)
| | - Santiago Sucre
- Division of Medical Oncology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA (A.A.A.R.)
| | - Cristina Ponce
- Division of Medical Oncology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA (A.A.A.R.)
| | - Ahmed Anwer Ali Rattani
- Division of Medical Oncology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA (A.A.A.R.)
| | - Mary Linton B. Peters
- Division of Medical Oncology, Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA (A.A.A.R.)
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3
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Montalban-Bravo G, Jabbour E, Chien K, Hammond D, Short N, Ravandi F, Konopleva M, Borthakur G, Daver N, Kanagal-Shammana R, Loghavi S, Qiao W, Huang X, Schneider H, Meyer M, Kantarjian H, Garcia-Manero G. Phase 1 study of azacitidine in combination with quizartinib in patients with FLT3 or CBL mutated MDS and MDS/MPN. Leuk Res 2024; 142:107518. [PMID: 38744144 DOI: 10.1016/j.leukres.2024.107518] [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: 03/19/2024] [Revised: 04/29/2024] [Accepted: 05/07/2024] [Indexed: 05/16/2024]
Abstract
We conducted a phase 1 study evaluating 3 dose levels of quizartinib (30 mg, 40 mg or 60 mg) in combination with azacitidine for HMA-naïve or relapsed/refractory MDS or MDS/MPN with FLT3 or CBL mutations. Overall, 12 patients (HMA naïve: n=9, HMA failure: n=3) were enrolled; 7 (58 %) patients had FLT3 mutations and 5 (42 %) had CBL mutations. The maximum tolerated dose was not reached. Most common grade 3-4 treatment-emergent adverse events were thrombocytopenia (n=5, 42 %), anemia (n=4, 33 %), lung infection (n=2, 17 %), skin infection (n=2, 17 %), hyponatremia (n=2, 17 %) and sepsis (n=2, 17 %). The overall response rate was 83 % with median relapse-free and overall survivals of 15.1 months (95 % CI 0.0-38.4 months) and 17.5 months (95 % CI NC-NC), respectively. FLT3 mutation clearance was observed in 57 % (n=4) patients. These data suggest quizartinib is safe and shows encouraging activity in FLT3-mutated MDS and MDS/MPN. This study is registered at Clinicaltrials.gov as NCT04493138.
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Affiliation(s)
| | - Elias Jabbour
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Kelly Chien
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Danielle Hammond
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Nicholas Short
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Farhad Ravandi
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Marina Konopleva
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Gautam Borthakur
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Naval Daver
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | | | - Sanam Loghavi
- Department of Hematopathology, The University of Texas MD Anderson Cancer Center, USA
| | - Wei Qiao
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, USA
| | - Xuelin Huang
- Department of Biostatistics, The University of Texas MD Anderson Cancer Center, USA
| | - Heather Schneider
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Meghan Meyer
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
| | - Hagop Kantarjian
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, USA
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4
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Nkosi D, Allbee AW, Rothberg PG, Friedberg JW, Evans AG. Common clonal origin of three distinct hematopoietic neoplasms in a single patient: B-cell lymphoma, T-cell lymphoma, and polycythemia vera. Cold Spring Harb Mol Case Stud 2023; 9:a006313. [PMID: 38199781 PMCID: PMC10815289 DOI: 10.1101/mcs.a006313] [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: 09/12/2023] [Accepted: 11/27/2023] [Indexed: 01/12/2024] Open
Abstract
The potential for more than one distinct hematolymphoid neoplasm to arise from a common mutated stem or precursor cell has been proposed based on findings in primary human malignancies. Particularly, angioimmunoblastic T-cell lymphoma (AITL), which shares a somatic mutation profile in common with other hematopoietic malignancies, has been reported to occur alongside myeloid neoplasms or clonal B-cell proliferations, with identical mutations occurring in more than one cell lineage. Here we report such a case of an elderly woman who was diagnosed over a period of 8 years with diffuse large B-cell lymphoma, polycythemia vera, and AITL, each harboring identical somatic mutations in multiple genes. Overall, at least five identical nucleotide mutations were shared across multiple specimens, with two identical mutations co-occurring at variable variant allele frequencies in all three specimen types. These findings lend credence to the theory that a common mutated stem cell could give rise to multiple neoplasms through parallel hematopoietic differentiation pathways.
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Affiliation(s)
- Dingani Nkosi
- Department of Pathology and Laboratory Medicine, University of Rochester, Rochester, New York 14642, USA
| | - Andrew W Allbee
- University of Rochester School of Medicine and Dentistry, University of Rochester, Rochester, New York 14642, USA
| | - Paul G Rothberg
- Department of Pathology and Laboratory Medicine, University of Rochester, Rochester, New York 14642, USA
| | - Jonathan W Friedberg
- Wilmot Cancer Institute, University of Rochester, Rochester, New York 14642, USA
| | - Andrew G Evans
- Department of Pathology and Laboratory Medicine, University of Rochester, Rochester, New York 14642, USA;
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5
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González-López O, Muñoz-González JI, Orfao A, Álvarez-Twose I, García-Montero AC. Comprehensive Analysis of Acquired Genetic Variants and Their Prognostic Impact in Systemic Mastocytosis. Cancers (Basel) 2022; 14:cancers14102487. [PMID: 35626091 PMCID: PMC9139197 DOI: 10.3390/cancers14102487] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2022] [Revised: 05/14/2022] [Accepted: 05/15/2022] [Indexed: 01/27/2023] Open
Abstract
Systemic mastocytosis (SM) is a rare clonal haematopoietic stem cell disease in which activating KIT mutations (most commonly KIT D816V) are present in virtually every (>90%) adult patient at similar frequencies among non-advanced and advanced forms of SM. The KIT D816V mutation is considered the most common pathogenic driver of SM. Acquisition of this mutation early during haematopoiesis may cause multilineage involvement of haematopoiesis by KIT D816V, which has been associated with higher tumour burden and additional mutations in other genes, leading to an increased rate of transformation to advanced SM. Thus, among other mutations, alterations in around 30 genes that are also frequently mutated in other myeloid neoplasms have been reported in SM cases. From these genes, 12 (i.e., ASXL1, CBL, DNMT3A, EZH2, JAK2, KRAS, NRAS, SF3B1, RUNX1, SF3B1, SRSF2, TET2) have been recurrently reported to be mutated in SM. Because of all the above, assessment of multilineage involvement of haematopoiesis by the KIT D816V mutation, in the setting of multi-mutated haematopoiesis as revealed by a limited panel of genes (i.e., ASXL1, CBL, DNMT3A, EZH2, NRAS, RUNX1 and SRSF2) and associated with a poorer patient outcome, has become of great help to identify SM patients at higher risk of disease progression and/or poor survival who could benefit from closer follow-up and eventually also early cytoreductive treatment.
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Affiliation(s)
- Oscar González-López
- Cancer Research Center (IBMCC, USAL/CSIC), Department of Medicine, Universidad de Salamanca, Biomedical Research Institute of Salamanca and Spanish Network on Mastocytosis (REMA), 37007 Salamanca, Spain; (O.G.-L.); (J.I.M.-G.); (A.O.)
- Centro de Investigación Biomédica en Red Cáncer (CIBERONC), 28029 Madrid, Spain;
| | - Javier I. Muñoz-González
- Cancer Research Center (IBMCC, USAL/CSIC), Department of Medicine, Universidad de Salamanca, Biomedical Research Institute of Salamanca and Spanish Network on Mastocytosis (REMA), 37007 Salamanca, Spain; (O.G.-L.); (J.I.M.-G.); (A.O.)
- Centro de Investigación Biomédica en Red Cáncer (CIBERONC), 28029 Madrid, Spain;
| | - Alberto Orfao
- Cancer Research Center (IBMCC, USAL/CSIC), Department of Medicine, Universidad de Salamanca, Biomedical Research Institute of Salamanca and Spanish Network on Mastocytosis (REMA), 37007 Salamanca, Spain; (O.G.-L.); (J.I.M.-G.); (A.O.)
- Centro de Investigación Biomédica en Red Cáncer (CIBERONC), 28029 Madrid, Spain;
| | - Iván Álvarez-Twose
- Centro de Investigación Biomédica en Red Cáncer (CIBERONC), 28029 Madrid, Spain;
- Instituto de Estudios de Mastocitosis de Castilla La Mancha (CLMast, Virgen del Valle Hospital) and REMA, 45071 Toledo, Spain
| | - Andrés C. García-Montero
- Cancer Research Center (IBMCC, USAL/CSIC), Department of Medicine, Universidad de Salamanca, Biomedical Research Institute of Salamanca and Spanish Network on Mastocytosis (REMA), 37007 Salamanca, Spain; (O.G.-L.); (J.I.M.-G.); (A.O.)
- Centro de Investigación Biomédica en Red Cáncer (CIBERONC), 28029 Madrid, Spain;
- Correspondence:
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6
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Distinct genomic landscape of Chinese pediatric acute myeloid leukemia impacts clinical risk classification. Nat Commun 2022; 13:1640. [PMID: 35347147 PMCID: PMC8960760 DOI: 10.1038/s41467-022-29336-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 03/09/2022] [Indexed: 12/17/2022] Open
Abstract
Studies have revealed key genomic aberrations in pediatric acute myeloid leukemia (AML) based on Western populations. It is unknown to what extent the current genomic findings represent populations with different ethnic backgrounds. Here we present the genomic landscape of driver alterations of Chinese pediatric AML and discover previously undescribed genomic aberrations, including the XPO1-TNRC18 fusion. Comprehensively comparing between the Chinese and Western AML cohorts reveal a substantially distinct genomic alteration profile. For example, Chinese AML patients more commonly exhibit mutations in KIT and CSF3R, and less frequently mutated of genes in the RAS signaling pathway. These differences in mutation frequencies lead to the detection of previously uncharacterized co-occurring mutation pairs. Importantly, the distinct driver profile is clinical relevant. We propose a refined prognosis risk classification model which better reflected the adverse event risk for Chinese AML patients. These results emphasize the importance of genetic background in precision medicine. The genomic landscape of pediatric acute myeloid leukemia (AML) has mostly been characterised for Western populations. Here, the authors identify potential driver alterations in Chinese pediatric AML, which differ from Western populations, and propose a prognostic risk classification model.
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7
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Role of CBL Mutations in Cancer and Non-Malignant Phenotype. Cancers (Basel) 2022; 14:cancers14030839. [PMID: 35159106 PMCID: PMC8833995 DOI: 10.3390/cancers14030839] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Revised: 02/04/2022] [Accepted: 02/05/2022] [Indexed: 12/30/2022] Open
Abstract
Simple Summary CBL mutations are progressively being described as involved in different clinical manifestations. Somatic CBL mutations can be found in different type of cancer. The clinical spectrum of germline mutations configures the so-called CBL syndrome, a cancer-predisposing condition that includes multisystemic involvement characterized by variable phenotypic expression and expressivity. In this review we provide an up-to-date review of the clinical manifestation of CBL mutations and of the molecular mechanisms in which CBL exerts its pathogenic role. Abstract CBL plays a key role in different cell pathways, mainly related to cancer onset and progression, hematopoietic development and T cell receptor regulation. Somatic CBL mutations have been reported in a variety of malignancies, ranging from acute myeloid leukemia to lung cancer. Growing evidence have defined the clinical spectrum of germline CBL mutations configuring the so-called CBL syndrome; a cancer-predisposing condition that also includes multisystemic involvement characterized by variable phenotypic expression and expressivity. This review provides a comprehensive overview of the molecular mechanisms in which CBL exerts its function and describes the clinical manifestation of CBL mutations in humans.
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8
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Lee P, Yim R, Yung Y, Chu HT, Yip PK, Gill H. Molecular Targeted Therapy and Immunotherapy for Myelodysplastic Syndrome. Int J Mol Sci 2021; 22:10232. [PMID: 34638574 PMCID: PMC8508686 DOI: 10.3390/ijms221910232] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/17/2021] [Accepted: 09/21/2021] [Indexed: 12/22/2022] Open
Abstract
Myelodysplastic syndrome (MDS) is a heterogeneous, clonal hematological disorder characterized by ineffective hematopoiesis, cytopenia, morphologic dysplasia, and predisposition to acute myeloid leukemia (AML). Stem cell genomic instability, microenvironmental aberrations, and somatic mutations contribute to leukemic transformation. The hypomethylating agents (HMAs), azacitidine and decitabine are the standard of care for patients with higher-risk MDS. Although these agents induce responses in up to 40-60% of patients, primary or secondary drug resistance is relatively common. To improve the treatment outcome, combinational therapies comprising HMA with targeted therapy or immunotherapy are being evaluated and are under continuous development. This review provides a comprehensive update of the molecular pathogenesis and immune-dysregulations involved in MDS, mechanisms of resistance to HMA, and strategies to overcome HMA resistance.
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Affiliation(s)
| | | | | | | | | | - Harinder Gill
- Division of Haematology, Medical Oncology and Haemopoietic Stem Cell Transplantation, Department of Medicine, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, China; (P.L.); (R.Y.); (Y.Y.); (H.-T.C.); (P.-K.Y.)
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9
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Aoyagi Y, Hayashi Y, Harada Y, Choi K, Matsunuma N, Sadato D, Maemoto Y, Ito A, Yanagi S, Starczynowski DT, Harada H. Mitochondrial Fragmentation Triggers Ineffective Hematopoiesis in Myelodysplastic Syndromes. Cancer Discov 2021; 12:250-269. [PMID: 34462274 DOI: 10.1158/2159-8290.cd-21-0032] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Revised: 07/04/2021] [Accepted: 08/24/2021] [Indexed: 11/16/2022]
Abstract
Ineffective hematopoiesis is a fundamental process leading to the pathogenesis of myelodysplastic syndromes (MDS). However, the pathobiological mediators of ineffective hematopoiesis in MDS remain unclear. Here, we demonstrated that overwhelming mitochondrial fragmentation in mutant hematopoietic stem cells and progenitors (HSC/Ps) triggers ineffective hematopoiesis in MDS. Mouse modeling of CBL exon-deletion with RUNX1 mutants, previously unreported co-mutations in MDS patients, recapitulated not only clinically relevant MDS phenotypes but also a distinct MDS-related gene signature. Mechanistically, dynamin-related protein 1 (DRP1)-dependent excessive mitochondrial fragmentation in HSC/Ps led to excessive ROS production, induced inflammatory signaling activation, and promoted subsequent dysplasia formation and impairment of granulopoiesis. Mitochondrial fragmentation was generally observed in patients with MDS. Pharmacological inhibition of DRP1 attenuated mitochondrial fragmentation and rescued ineffective hematopoiesis phenotypes in MDS mice. These findings provide mechanistic insights into ineffective hematopoiesis and indicate that dysregulated mitochondrial dynamics could be a therapeutic target for bone marrow failure in MDS.
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Affiliation(s)
- Yasushige Aoyagi
- Laboratory of Oncology, Tokyo University of Pharmacy and Life Sciences
| | - Yoshihiro Hayashi
- Laboratory of Oncology, Tokyo University of Pharmacy and Life Sciences
| | - Yuka Harada
- Clinical Laboratory Medicine, Tokyo Metropolitan Cancer and Infectious Diseases Center Komagome Hospital
| | - Kwangmin Choi
- Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center
| | - Natsumi Matsunuma
- Laboratory of Oncology, Tokyo University of Pharmacy and Life Sciences
| | - Daichi Sadato
- Clinical Research Center, Tokyo Metropolitan Cancer and Infectious Diseases Center, Komagome Hospital
| | - Yuki Maemoto
- Laboratory of Cell Signaling, School of Life Sciences,, Tokyo University of Pharmacy and Life Sciences
| | - Akihiro Ito
- School of Life Sciences, Tokyo University of Pharmacy and Life Sciences
| | - Shigeru Yanagi
- School of Life Science, Tokyo University of Pharmacy and Life Sciences
| | - Daniel T Starczynowski
- Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center
| | - Hironori Harada
- Laboratory of Oncology, School of Life Science, Tokyo University of Pharmacy and Life Sciences
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10
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CBL mutations drive PI3K/AKT signaling via increased interaction with LYN and PIK3R1. Blood 2021; 137:2209-2220. [PMID: 33512474 DOI: 10.1182/blood.2020006528] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 12/14/2020] [Indexed: 12/13/2022] Open
Abstract
Casitas B-lineage lymphoma (CBL) encodes an E3 ubiquitin ligase and signaling adaptor that regulates receptor and nonreceptor tyrosine kinases. Recurrent CBL mutations occur in myeloid neoplasms, including 10% to 20% of chronic myelomonocytic leukemia (CMML) cases, and selectively disrupt the protein's E3 ubiquitin ligase activity. CBL mutations have been associated with poor prognosis, but the oncogenic mechanisms and therapeutic implications of CBL mutations remain incompletely understood. We combined functional assays and global mass spectrometry to define the phosphoproteome, CBL interactome, and mechanism of signaling activation in a panel of cell lines expressing an allelic series of CBL mutations. Our analyses revealed that increased LYN activation and interaction with mutant CBL are key drivers of enhanced CBL phosphorylation, phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1) recruitment, and downstream phosphatidylinositol 3-kinase (PI3K)/AKT signaling in CBL-mutant cells. Signaling adaptor domains of CBL, including the tyrosine kinase-binding domain, proline-rich region, and C-terminal phosphotyrosine sites, were all required for the oncogenic function of CBL mutants. Genetic ablation or dasatinib-mediated inhibition of LYN reduced CBL phosphorylation, CBL-PIK3R1 interaction, and PI3K/AKT signaling. Furthermore, we demonstrated in vitro and in vivo antiproliferative efficacy of dasatinib in CBL-mutant cell lines and primary CMML. Overall, these mechanistic insights into the molecular function of CBL mutations provide rationale to explore the therapeutic potential of LYN inhibition in CBL-mutant myeloid malignancies.
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11
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Jian J, Qiao Y, Li Y, Guo Y, Ma H, Liu B. Mutations in chronic myelomonocytic leukemia and their prognostic relevance. Clin Transl Oncol 2021; 23:1731-1742. [PMID: 33861431 DOI: 10.1007/s12094-021-02585-x] [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: 11/26/2020] [Accepted: 03/06/2021] [Indexed: 12/19/2022]
Abstract
Chronic myelomonocytic leukemia (CMML) is a hematologic malignancy that overlaps with myeloproliferative neoplasms (MPN) and myelodysplastic syndromes (MDS) and tends to transform into acute myeloid leukemia (AML). Among cases of CMML, > 90% have gene mutations, primarily involving TET2 (~ 60%), ASXL1 (~ 40%), SRSF2 (~ 50%), and the RAS pathways (~ 30%). These gene mutations are associated with both the clinical phenotypes and the prognosis of CMML, special CMML variants and pre-phases of CMML. Cytogenetic abnormalities and the size of genome are also associated with prognosis. Meanwhile, cases with ASXL1, DNMT3A, NRAS, SETBP1, CBL and RUNX1 mutations may have inferior prognoses, but only ASXL1 mutations were confirmed to be independent predictors of the patient outcome and were included in three prognostic models. Novel treatment targets related to the various gene mutations are emerging. Therefore, this review provides new insights to explore the correlations among gene mutations, clinical phenotypes, prognosis, and novel drugs in CMML.
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Affiliation(s)
- J Jian
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China
| | - Y Qiao
- Institute of Hematology, Xi'an Central Hospital, Xi'an, Shaanxi, China
| | - Y Li
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China
| | - Y Guo
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China
| | - H Ma
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China. .,Department of Hematology, The First Affiliated Hospital, Lanzhou University, 1 Donggangxilu street, Lanzhou, Gansu, China.
| | - B Liu
- The First Clinical Medical College, Lanzhou University, Lanzhou, Gansu, China. .,Department of Hematology, The First Affiliated Hospital, Lanzhou University, 1 Donggangxilu street, Lanzhou, Gansu, China.
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12
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Venanzi A, Marra A, Schiavoni G, Milner SG, Limongello R, Santi A, Pettirossi V, Ultimo S, Tasselli L, Pucciarini A, Falini L, Sciabolacci S, Martelli MP, Sportoletti P, Ascani S, Falini B, Tiacci E. Dissecting Clonal Hematopoiesis in Tissues of Classical Hodgkin Lymphoma Patients. Blood Cancer Discov 2021; 2:216-225. [PMID: 34164626 DOI: 10.1158/2643-3230.bcd-20-0203] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Clonal hematopoiesis predisposes to hematological malignancies. However, clonal hematopoiesis is understudied in classical Hodgkin lymphoma (cHL), a mature B-cell neoplasm exhibiting the most abundant microenvironment. We analyzed clonal hematopoiesis in 40 cHL cases by sequencing microdissected tumor cells and matched normal cells from blood and/or lymph nodes. Five patients had blood and/or tissue clonal hematopoiesis. In three of five patients (all failing first-line therapy), clonal hematopoiesis spread through the tissue microenvironment extensively, and featured mutant DNMT3AR882H , KRASG60D and DNMT3AR882H +TET2Q1274 * in 33%, 92% and 60% of non-neoplastic cells, respectively. In the latter case, DNMT3A/TET2-mutant clonal hematopoiesis seeded the neoplastic clone, which was infected by the Epstein-Barr virus and showed almost no other somatic mutations exome-wide. In the former case, DNMT3A-mutant clonal hematopoiesis did not originate the neoplastic clone despite dominating the blood and B-cell lineage (~94% leukocytes; ~96% mature blood B cells), yet led to NPM1-mutated acute myeloid leukemia 6 years after therapy for cHL. Our results expand to cHL the spectrum of hematologic malignancies associated with clonal hematopoiesis.
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Affiliation(s)
- Alessandra Venanzi
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Andrea Marra
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Gianluca Schiavoni
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Sara G Milner
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Roberto Limongello
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Alessia Santi
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Valentina Pettirossi
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Simona Ultimo
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Luisa Tasselli
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Alessandra Pucciarini
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Lorenza Falini
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Sofia Sciabolacci
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Maria Paola Martelli
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Paolo Sportoletti
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Stefano Ascani
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Brunangelo Falini
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
| | - Enrico Tiacci
- Institute of Hematology and Center for Hemato-Oncology Research, University and Hospital of Perugia - Italy
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13
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Ramos Perez J, Montalban-Bravo G. Emerging drugs for the treatment of chronic myelomonocytic leukemia. Expert Opin Emerg Drugs 2020; 25:515-529. [PMID: 33280448 DOI: 10.1080/14728214.2020.1854224] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Introduction: Chronic myelomonocytic leukemia (CMML) is a clonal hematologic disorder with heterogenous prognosis, but with no curative therapies with exception of allogeneic transplant. Therapeutic options for patients with CMML are limited, and although hypomethylating agents such as azacitidine and decitabine are the standard of care, only 40% of patients achieve a response, and most responses are transient. Over the last 5 years, significant advances have been made in the understanding of the clonal landscape of CMML, some of the mechanisms associated to resistance to HMA, and other key biological processes involved in disease pathogenesis. Areas covered: The current article reviews the most relevant emerging therapies currently undergoing clinical trials for the treatment of previously untreated or relapsed CMML. Expert opinion: The presence of recurrent somatic mutations in CMML represents therapeutic opportunities to utilize specific small molecule inhibitors such as IDH, FLT3, MEK/ERK, PLK1, or splicing inhibitors and modulators. In addition, other novel agents such as immune therapies, BCL2 or MCL1 inhibitors and other monoclonal antibodies could lead to therapeutic advances. Identifying specific patient populations likely to benefit from some of these interventions, and development of optimal combinations will remain the challenge when determining their role in therapy.
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Affiliation(s)
- Jorge Ramos Perez
- Department of Leukemia, The University of Texas MD Anderson Cancer Center , Houston, TX, USA
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14
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Weisberg E, Meng C, Case AE, Tiv HL, Gokhale PC, Toure AA, Buhrlage S, Liu X, Wang J, Gray N, Stone R, Adamia S, Winer E, Sattler M, Griffin JD. The combination of FLT3 and SYK kinase inhibitors is toxic to leukaemia cells with CBL mutations. J Cell Mol Med 2020; 24:2145-2156. [PMID: 31943762 PMCID: PMC7011134 DOI: 10.1111/jcmm.14820] [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: 06/12/2019] [Revised: 10/28/2019] [Accepted: 11/02/2019] [Indexed: 12/13/2022] Open
Abstract
Mutations in the E3 ubiquitin ligase CBL, found in several myeloid neoplasms, lead to decreased ubiquitin ligase activity. In murine systems, these mutations are associated with cytokine-independent proliferation, thought to result from the activation of hematopoietic growth receptors, including FLT3 and KIT. Using cell lines and primary patient cells, we compared the activity of a panel of FLT3 inhibitors currently being used or tested in AML patients and also evaluated the effects of inhibition of the non-receptor tyrosine kinase, SYK. We show that FLT3 inhibitors ranging from promiscuous to highly targeted are potent inhibitors of growth of leukaemia cells expressing mutant CBL in vitro, and we demonstrate in vivo efficacy of midostaurin using mouse models of mutant CBL. Potentiation of effects of targeted FLT3 inhibition by SYK inhibition has been demonstrated in models of mutant FLT3-positive AML and AML characterized by hyperactivated SYK. Here, we show that targeted SYK inhibition similarly enhances the effects of midostaurin and other FLT3 inhibitors against mutant CBL-positive leukaemia. Taken together, our results support the notion that mutant CBL-expressing myeloid leukaemias are highly sensitive to available FLT3 inhibitors and that this effect can be significantly augmented by optimum inhibition of SYK kinase.
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Affiliation(s)
- Ellen Weisberg
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Chengcheng Meng
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Abigail E Case
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Hong L Tiv
- Experimental Therapeutics Core and Belfer Center for Applied Cancer Science, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Prafulla C Gokhale
- Experimental Therapeutics Core and Belfer Center for Applied Cancer Science, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Anthia A Toure
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Sara Buhrlage
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Xiaoxi Liu
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Jinhua Wang
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Nathanael Gray
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Richard Stone
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Sophia Adamia
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Eric Winer
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Martin Sattler
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - James D Griffin
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
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15
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Azrakhsh NA, Mensah-Glanowska P, Sand K, Kittang AO. Targeting Immune Signaling Pathways in Clonal Hematopoiesis. Curr Med Chem 2019; 26:5262-5277. [PMID: 30907306 DOI: 10.2174/0929867326666190325100636] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 03/05/2019] [Accepted: 03/12/2019] [Indexed: 12/15/2022]
Abstract
BACKGROUND Myeloid neoplasms are a diverse group of malignant diseases with different entities and numerous patho-clinical features. They arise from mutated clones of hematopoietic stem- and progenitor cells which expand by outperforming their normal counterparts. The intracellular signaling profile of cancer cells is the sum of genetic, epigenetic and microenvironmental influences, and the multiple interconnections between different signaling pathways make pharmacological targeting complicated. OBJECTIVE To present an overview of known somatic mutations in myeloproliferative neoplasms (MPN), myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) and the inflammatory signaling pathways affected by them, as well as current efforts to therapeutically modulate this aberrant inflammatory signaling. METHODS In this review, we extensively reviewed and compiled salient information with ClinicalTrials.gov as our source on ongoing studies, and PubMed as our authentic bibliographic source, using a focused review question. RESULTS Mutations affecting immune signal transduction are present to varying extents in clonal myeloid diseases. While MPN are dominated by a few common mutations, a multitude of different genes can be mutated in MDS and AML. Mutations can also occur in asymptomatic persons, a finding called clonal hematopoiesis of indeterminate potential (CHIP). Mutations in FLT3, JAK, STAT, CBL and RAS can lead to aberrant immune signaling. Protein kinase inhibitors are entering the clinic and are extensively investigated in clinical trials in MPN, MDS and AML. CONCLUSION In summary, this article summarizes recent research on aberrant inflammatory signaling in clonal myeloid diseases and the clinical therapeutic potential of modulation of signal transduction and effector proteins in the affected pathways.
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Affiliation(s)
| | - Patrycja Mensah-Glanowska
- Department of Hematology, Jagiellonian University Medical College / University Hospital, Krakow, Poland
| | - Kristoffer Sand
- Clinic of Medicine and Rehabilitation, More and Romsdal Hospital Trust, Alesund, Norway
| | - Astrid Olsnes Kittang
- Department of Clinical Science, University of Bergen, Bergen, Norway.,Department of Medicine, Section for Hematology, Haukeland University Hospital, Bergen, Norway
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16
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Kazi JU, Rönnstrand L. FMS-like Tyrosine Kinase 3/FLT3: From Basic Science to Clinical Implications. Physiol Rev 2019; 99:1433-1466. [PMID: 31066629 DOI: 10.1152/physrev.00029.2018] [Citation(s) in RCA: 103] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
FMS-like tyrosine kinase 3 (FLT3) is a receptor tyrosine kinase that is expressed almost exclusively in the hematopoietic compartment. Its ligand, FLT3 ligand (FL), induces dimerization and activation of its intrinsic tyrosine kinase activity. Activation of FLT3 leads to its autophosphorylation and initiation of several signal transduction cascades. Signaling is initiated by the recruitment of signal transduction molecules to activated FLT3 through binding to specific phosphorylated tyrosine residues in the intracellular region of FLT3. Activation of FLT3 mediates cell survival, cell proliferation, and differentiation of hematopoietic progenitor cells. It acts in synergy with several other cytokines to promote its biological effects. Deregulated FLT3 activity has been implicated in several diseases, most prominently in acute myeloid leukemia where around one-third of patients carry an activating mutant of FLT3 which drives the disease and is correlated with poor prognosis. Overactivity of FLT3 has also been implicated in autoimmune diseases, such as rheumatoid arthritis. The observation that gain-of-function mutations of FLT3 can promote leukemogenesis has stimulated the development of inhibitors that target this receptor. Many of these are in clinical trials, and some have been approved for clinical use. However, problems with acquired resistance to these inhibitors are common and, furthermore, only a fraction of patients respond to these selective treatments. This review provides a summary of our current knowledge regarding structural and functional aspects of FLT3 signaling, both under normal and pathological conditions, and discusses challenges for the future regarding the use of targeted inhibition of these pathways for the treatment of patients.
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Affiliation(s)
- Julhash U Kazi
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University , Lund , Sweden ; Lund Stem Cell Center, Department of Laboratory Medicine, Lund University , Lund , Sweden ; and Division of Oncology, Skåne University Hospital , Lund , Sweden
| | - Lars Rönnstrand
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University , Lund , Sweden ; Lund Stem Cell Center, Department of Laboratory Medicine, Lund University , Lund , Sweden ; and Division of Oncology, Skåne University Hospital , Lund , Sweden
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17
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Weisberg E, Meng C, Case AE, Sattler M, Tiv HL, Gokhale PC, Buhrlage SJ, Liu X, Yang J, Wang J, Gray N, Stone RM, Adamia S, Dubreuil P, Letard S, Griffin JD. Comparison of effects of midostaurin, crenolanib, quizartinib, gilteritinib, sorafenib and BLU-285 on oncogenic mutants of KIT, CBL and FLT3 in haematological malignancies. Br J Haematol 2019; 187:488-501. [PMID: 31309543 DOI: 10.1111/bjh.16092] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 05/21/2019] [Indexed: 12/27/2022]
Abstract
Mutations in two type-3 receptor tyrosine kinases (RTKs), KIT and FLT3, are common in both acute myeloid leukaemia (AML) and systemic mastocytosis (SM) and lead to hyperactivation of key signalling pathways. A large number of tyrosine kinase inhibitors (TKIs) have been developed that target either FLT3 or KIT and significant clinical benefit has been demonstrated in multiple clinical trials. Given the structural similarity of FLT3 and KIT, it is not surprising that some of these TKIs inhibit both of these receptors. This is typified by midostaurin, which has been approved by the US Food and Drug Administration for mutant FLT3-positive AML and for KIT D816V-positive SM. Here, we compare the in vitro activities of the clinically available FLT3 and KIT inhibitors with those of midostaurin against a panel of cells expressing a variety of oncogenic FLT3 or KIT receptors, including wild-type (wt) FLT3, FLT3-internal tandem duplication (ITD), FLT3 D835Y, the resistance mutant FLT3-ITD+ F691L, KIT D816V, and KIT N822K. We also examined the effects of these inhibitors in vitro and in vivo on cells expressing mutations in c-CBL found in AML that result in hypersensitization of RTKs, such as FLT3 and KIT. The results show a wide spectrum of activity of these various mutations to these clinically available TKIs.
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Affiliation(s)
- Ellen Weisberg
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Chengcheng Meng
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Abigail E Case
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Martin Sattler
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Hong L Tiv
- Experimental Therapeutics Core and Belfer Center for Applied Cancer Science, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Prafulla C Gokhale
- Experimental Therapeutics Core and Belfer Center for Applied Cancer Science, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Sara J Buhrlage
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Xiaoxi Liu
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Jing Yang
- Department of Cancer Biology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - Jinhua Wang
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Nathanael Gray
- Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Richard M Stone
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Sophia Adamia
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Patrice Dubreuil
- CRCM, [Signalling, Haematopoiesis and Mechanism of Oncogenesis, Equipe Labellisée Ligue Contre le Cancer], Inserm, U1068; Institut Paoli-Calmettes; Aix-Marseille University, Marseille, France
| | - Sebastien Letard
- CRCM, [Signalling, Haematopoiesis and Mechanism of Oncogenesis, Equipe Labellisée Ligue Contre le Cancer], Inserm, U1068; Institut Paoli-Calmettes; Aix-Marseille University, Marseille, France
| | - James D Griffin
- Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
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18
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Tobiasson M, Kittang AO. Treatment of myelodysplastic syndrome in the era of next-generation sequencing. J Intern Med 2019; 286:41-62. [PMID: 30869816 DOI: 10.1111/joim.12893] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Next-generation sequencing (NGS) is rapidly changing the clinical care of patients with myelodysplastic syndrome (MDS). NGS can be used for various applications: (i) in the diagnostic process to discriminate between MDS and other diseases such as aplastic anaemia, myeloproliferative disorders and idiopathic cytopenias; (ii) for classification, for example, where the presence of SF3B1 mutation is one criterion for the ring sideroblast anaemia subgroups in the World Health Organization 2016 classification; (iii) for identification of patients suitable for targeted therapy (e.g. IDH1/2 inhibitors); (iv) for prognostication, for example, where specific mutations (e.g. TP53 and RUNX1) are associated with inferior prognosis, whereas others (e.g. SF3B1) are associated with superior prognosis; and (v) to monitor patients for progression or treatment failure. Most commonly, targeted sequencing for genes (normally 50-100 genes) reported to be recurrently mutated in myeloid disease is used. At present, NGS is rarely incorporated into clinical guidelines although an increasing number of studies have demonstrated the benefit of using NGS in the clinical management of MDS patients.
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Affiliation(s)
- M Tobiasson
- Department of Hematology, Karolinska University Hospital, Stockholm, Sweden.,Institution of Medicine Huddinge, Karolinska Institute, Stockholm, Sweden
| | - A O Kittang
- Department of Clinical Science, University of Bergen, Bergen, Norway.,Section for Hematology, Department of Medicine, Haukeland University Hospital, Bergen, Norway
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19
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B7-H3 promotes multiple myeloma cell survival and proliferation by ROS-dependent activation of Src/STAT3 and c-Cbl-mediated degradation of SOCS3. Leukemia 2018; 33:1475-1486. [PMID: 30573782 DOI: 10.1038/s41375-018-0331-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 10/17/2018] [Accepted: 11/16/2018] [Indexed: 12/16/2022]
Abstract
B7-H3 (CD276) is broadly overexpressed by multiple human cancers. It plays a vital role in tumor progression and has been accepted as one of the inhibitory B7 family checkpoint molecules. To identify the functions and underlying mechanisms of B7-H3 in multiple myeloma, we analyzed B7-H3 expression in myeloma patients and used siRNAs and overexpression plasmid of B7-H3 to investigate its roles and downstream signaling molecules in myeloma cell lines. The results showed that surface expression of B7-H3 was upregulated in myeloma samples and cell lines. Lower expression of B7-H3 in myeloma cells was associated with better progression-free survival. Myeloma cell survival, drug resistance, and tumor growth could be promoted by B7-H3. The molecular basis for these functional roles of B7-H3 involved the activation of JAK2/STAT3 via redox-mediated oxidation and activation of Src. We further identified a STAT3-promoting signaling pathway by which oxidant-mediated Src phosphorylation led to secondary activation of the E3 ubiquitin ligase c-Cbl. Activated c-Cbl subsequently caused specific proteasomal degradation of SOCS3, a negative regulator of JAK2/STAT3. These data indicate B7-H3's important role in the activation of ROS/Src/c-Cbl pathway in multiple myeloma which integrates redox regulation and sustained STAT3 activation at the level of degradation of STAT3 suppressor.
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20
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Hyrenius-Wittsten A, Pilheden M, Sturesson H, Hansson J, Walsh MP, Song G, Kazi JU, Liu J, Ramakrishan R, Garcia-Ruiz C, Nance S, Gupta P, Zhang J, Rönnstrand L, Hultquist A, Downing JR, Lindkvist-Petersson K, Paulsson K, Järås M, Gruber TA, Ma J, Hagström-Andersson AK. De novo activating mutations drive clonal evolution and enhance clonal fitness in KMT2A-rearranged leukemia. Nat Commun 2018; 9:1770. [PMID: 29720585 PMCID: PMC5932012 DOI: 10.1038/s41467-018-04180-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 04/11/2018] [Indexed: 02/07/2023] Open
Abstract
Activating signaling mutations are common in acute leukemia with KMT2A (previously MLL) rearrangements (KMT2A-R). These mutations are often subclonal and their biological impact remains unclear. Using a retroviral acute myeloid mouse leukemia model, we demonstrate that FLT3ITD, FLT3N676K, and NRASG12D accelerate KMT2A-MLLT3 leukemia onset. Further, also subclonal FLT3N676K mutations accelerate disease, possibly by providing stimulatory factors. Herein, we show that one such factor, MIF, promotes survival of mouse KMT2A-MLLT3 leukemia initiating cells. We identify acquired de novo mutations in Braf, Cbl, Kras, and Ptpn11 in KMT2A-MLLT3 leukemia cells that favored clonal expansion. During clonal evolution, we observe serial genetic changes at the KrasG12D locus, consistent with a strong selective advantage of additional KrasG12D. KMT2A-MLLT3 leukemias with signaling mutations enforce Myc and Myb transcriptional modules. Our results provide new insight into the biology of KMT2A-R leukemia with subclonal signaling mutations and highlight the importance of activated signaling as a contributing driver. In acute leukemia with KMT2A rearrangements (KMT2A-R), activating signaling mutations are common. Here, the authors use a retroviral acute myeloid mouse leukemia model to show that subclonal de novo activating mutations drive clonal evolution in acute leukemia with KMT2A-R and enhance clonal fitness.
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Affiliation(s)
- Axel Hyrenius-Wittsten
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Mattias Pilheden
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Helena Sturesson
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Jenny Hansson
- Division of Molecular Hematology, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Michael P Walsh
- Department of Pathology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA
| | - Guangchun Song
- Department of Pathology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA
| | - Julhash U Kazi
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University, 223 63, Lund, Sweden
| | - Jian Liu
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Ramprasad Ramakrishan
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Cristian Garcia-Ruiz
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Stephanie Nance
- Department of Oncology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA
| | - Pankaj Gupta
- Department of Computational Biology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA
| | - Jinghui Zhang
- Department of Computational Biology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA
| | - Lars Rönnstrand
- Division of Translational Cancer Research, Department of Laboratory Medicine, Lund University, 223 63, Lund, Sweden.,Lund Stem Cell Center, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden.,Division of Oncology, Skane University Hospital, Lund University, 221 85, Lund, Sweden
| | - Anne Hultquist
- Department of Pathology, Skane University Hospital, Lund University, 221 85, Lund, Sweden
| | - James R Downing
- Department of Pathology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA
| | - Karin Lindkvist-Petersson
- Medical Structural Biology, Department of Experimental Medical Science, 221 84 Lund University, Lund, Sweden
| | - Kajsa Paulsson
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Marcus Järås
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden
| | - Tanja A Gruber
- Department of Pathology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA.,Department of Oncology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA
| | - Jing Ma
- Department of Pathology, St. Jude Children´s Research Hospital, Memphis, TN, 38105, USA
| | - Anna K Hagström-Andersson
- Division of Clinical Genetics, Department of Laboratory Medicine, Lund University, 221 84, Lund, Sweden.
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21
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Myelodysplastic Syndrome/Acute Myeloid Leukemia Arising in Idiopathic Erythrocytosis. Case Rep Hematol 2018; 2018:4378310. [PMID: 29682367 PMCID: PMC5842720 DOI: 10.1155/2018/4378310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Accepted: 02/07/2018] [Indexed: 11/17/2022] Open
Abstract
The term “idiopathic erythrocytosis (IE)” is applied to those cases where a causal clinical or pathological event cannot be elucidated and likely reflects a spectrum of underlying medical and molecular abnormalities. The clinical course of a patient with IE is described manifesting as a persistent erythrocytosis with a low serum erythropoietin level, mild eosinophilia, and with evidence of a thrombotic event. The patient subsequently developed a myelodysplasic syndrome (MDS) and acute myeloid leukemia (AML), an event not observed in erythrocytosis patients other than those with polycythemia vera (PV). Application of a next-generation sequencing (NGS) approach targeted for myeloid malignancies confirmed wild-type JAK2 exons 12–15 and identified a common SH2B3 W262R single-nucleotide polymorphism associated with the development of hematological features of myeloproliferative neoplasms (MPNs). Further NGS analysis detected a CBL L380P mutated clone expanding in parallel with the development of MDS and subsequent AML. Despite the absence of JAK2, MPL exon 10, or CALR exon 9 mutations, a similarity with the disease course of PV/MPN was evident. A clonal link between the erythrocytosis and AML could be neither confirmed nor excluded. Future molecular identification of the mechanisms underlying IE is likely to provide a more refined therapeutic approach.
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22
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Seong MW, Ka SH, Park JH, Park JH, Yoo HM, Yang SW, Park JM, Park D, Lee ST, Seol JH, Chung CH. Deleterious c-Cbl Exon Skipping Contributes to Human Glioma. Neoplasia 2016; 17:518-24. [PMID: 26152360 PMCID: PMC4719003 DOI: 10.1016/j.neo.2015.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 06/02/2015] [Accepted: 06/08/2015] [Indexed: 11/29/2022] Open
Abstract
c-Cbl, a RING-type ubiquitin E3 ligase, downregulates various receptor tyrosine kinases (e.g., epidermal growth factor receptor (EGFR)), leading to inhibition of cell proliferation. Moreover, patients with myeloid neoplasm frequently harbor c-Cbl mutations, implicating the role of c-Cbl as a tumor suppressor. Recently, we have shown that c-Cbl downregulates αPix-mediated cell migration and invasion, and the lack of c-Cbl in the rat C6 and human A172 glioma cells is responsible for their malignant behavior. Here, we showed that c-Cbl exon skipping occurs in the glioma cells and the brain tissues from glioblastoma patients lacking c-Cbl. This exon skipping resulted in generation of two types of c-Cbl isoforms: type I lacking exon-9 and type II lacking exon-9 and exon-10. However, the c-Cbl isoforms in the cells and tissues could not be detected as they were rapidly degraded by proteasome. Consequently, C6 and A172 cells showed sustained EGFR activation. However, no splice site mutation was found in the region from exon-7 to exon-11 of the c-Cbl gene in C6 cells and a glioblastoma tissue lacking c-Cbl. In addition, c-Cbl exon skipping could be induced when cells transfected with a c-Cbl mini-gene were grown to high density or under hypoxic stress. These results suggest that unknown alternations (e.g., mutation) of splicing machinery in C6 and A172 cells and the glioblastoma brain tissues are responsible for the deleterious exon skipping. Collectively, these findings indicate that the c-Cbl exon skipping contributes to human glioma and its malignant behavior.
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Affiliation(s)
- Min Woo Seong
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Seung Hyeun Ka
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Ji Ho Park
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Jong Ho Park
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Hee Min Yoo
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Seung Wook Yang
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Jung Mi Park
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Dongeun Park
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea
| | - Soon Tae Lee
- Department of Neurology, Seoul National University Hospital, Seoul, Korea
| | - Jae Hong Seol
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea.
| | - Chin Ha Chung
- School of Biological Sciences and Institute for Protein Metabolism and Diseases, College of Natural Sciences, Seoul National University, Seoul, Korea.
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23
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Akin DF, Oner DA, Mumcuoglu M, Ezer U, Bahce M, Kurekci E, Akar N. Detection of TET2, KRAS and CBL variants by Next Generation Sequencing and analysis of their correlation with JAK2 and FLT3 in childhood AML. EGYPTIAN JOURNAL OF MEDICAL HUMAN GENETICS 2016. [DOI: 10.1016/j.ejmhg.2015.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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24
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Katzav S, Schmitz ML. Mutations of c-Cbl in myeloid malignancies. Oncotarget 2016; 6:10689-96. [PMID: 26028666 PMCID: PMC4484412 DOI: 10.18632/oncotarget.3986] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 04/15/2015] [Indexed: 12/18/2022] Open
Abstract
Next generation sequencing has shown the frequent occurrence of point mutations in the ubiquitin E3 ligase c-Cbl in myeloid malignancies. Mouse models revealed a causal contribution of c-Cbl for the onset of such neoplasms. The point mutations typically cluster in the linker region and RING finger domain and affect both alleles by acquired uniparental disomy. The fast progress in the detection of c-Cbl mutations is contrasted by our scarce knowledge on their functional consequences. The c-Cbl protein displays several enzymatic functions by promoting the attachment of differentially composed ubiquitin chains and of the ubiquitin-like protein NEDD8 to its target proteins. In addition, c-Cbl functions as an adapter protein and undergoes phosphorylation-dependent inducible conformation changes. Studies on the impact of c-Cbl mutations on its functions as a dynamic and versatile adapter protein, its interactomes and on its various enzymatic activities are now important to allow the identification of druggable targets within the c-Cbl signaling network.
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Affiliation(s)
- Shulamit Katzav
- Developmental Biology and Cancer Research, IMRIC, Faculty of Medicine, The Hebrew University, Jerusalem, Israel
| | - M Lienhard Schmitz
- Institute of Biochemistry, University of Giessen, Friedrichstrasse, Giessen, Germany
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25
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Goyama S, Schibler J, Gasilina A, Shrestha M, Lin S, Link KA, Chen J, Whitman SP, Bloomfield CD, Nicolet D, Assi SA, Ptasinska A, Heidenreich O, Bonifer C, Kitamura T, Nassar NN, Mulloy JC. UBASH3B/Sts-1-CBL axis regulates myeloid proliferation in human preleukemia induced by AML1-ETO. Leukemia 2015; 30:728-39. [PMID: 26449661 DOI: 10.1038/leu.2015.275] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Revised: 09/22/2015] [Accepted: 09/30/2015] [Indexed: 12/24/2022]
Abstract
The t(8;21) rearrangement, which creates the AML1-ETO fusion protein, represents the most common chromosomal translocation in acute myeloid leukemia (AML). Clinical data suggest that CBL mutations are a frequent event in t(8;21) AML, but the role of CBL in AML1-ETO-induced leukemia has not been investigated. In this study, we demonstrate that CBL mutations collaborate with AML1-ETO to expand human CD34+ cells both in vitro and in a xenograft model. CBL depletion by shRNA also promotes the growth of AML1-ETO cells, demonstrating the inhibitory function of endogenous CBL in t(8;21) AML. Mechanistically, loss of CBL function confers hyper-responsiveness to thrombopoietin and enhances STAT5/AKT/ERK/Src signaling in AML1-ETO cells. Interestingly, we found the protein tyrosine phosphatase UBASH3B/Sts-1, which is known to inhibit CBL function, is upregulated by AML1-ETO through transcriptional and miR-9-mediated regulation. UBASH3B/Sts-1 depletion induces an aberrant pattern of CBL phosphorylation and impairs proliferation in AML1-ETO cells. The growth inhibition caused by UBASH3B/Sts-1 depletion can be rescued by ectopic expression of CBL mutants, suggesting that UBASH3B/Sts-1 supports the growth of AML1-ETO cells partly through modulation of CBL function. Our study reveals a role of CBL in restricting myeloid proliferation of human AML1-ETO-induced leukemia, and identifies UBASH3B/Sts-1 as a potential target for pharmaceutical intervention.
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Affiliation(s)
- S Goyama
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA.,Division of Cellular Therapy, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - J Schibler
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - A Gasilina
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - M Shrestha
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - S Lin
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - K A Link
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - J Chen
- Section of Hematology/Oncology, Department of Medicine, University of Chicago, Chicago, IL, USA
| | - S P Whitman
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
| | - C D Bloomfield
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
| | - D Nicolet
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA.,Alliance for Clinical Trials in Oncology Statistics and Data Center, Mayo Clinic, Rochester, MN, USA
| | - S A Assi
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - A Ptasinska
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - O Heidenreich
- Northern Institute for Cancer Research, Newcastle University, Newcastle upon Tyne, UK
| | - C Bonifer
- Institute of Cancer and Genomic Sciences, University of Birmingham, Birmingham, UK
| | - T Kitamura
- Division of Cellular Therapy, The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
| | - N N Nassar
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - J C Mulloy
- Division of Experimental Hematology and Cancer Biology, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH, USA
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26
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Peng X, Dong M, Ma L, Jia XE, Mao J, Jin C, Chen Y, Gao L, Liu X, Ma K, Wang L, Du T, Jin Y, Huang Q, Li K, Zon LI, Liu T, Deng M, Zhou Y, Xi X, Zhou Y, Chen S. A point mutation of zebrafish c-cbl gene in the ring finger domain produces a phenotype mimicking human myeloproliferative disease. Leukemia 2015; 29:2355-65. [PMID: 26104663 DOI: 10.1038/leu.2015.154] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2015] [Revised: 05/09/2015] [Accepted: 05/12/2015] [Indexed: 12/12/2022]
Abstract
Controlled self-renewal and differentiation of hematopoietic stem/progenitor cells (HSPCs) are critical for vertebrate development and survival. These processes are tightly regulated by the transcription factors, signaling molecules and epigenetic factors. Impaired regulations of their function could result in hematological malignancies. Using a large-scale zebrafish N-ethyl-N-nitrosourea mutagenesis screening, we identified a line named LDD731, which presented significantly increased HSPCs in hematopoietic organs. Further analysis revealed that the cells of erythroid/myeloid lineages in definitive hematopoiesis were increased while the primitive hematopoiesis was not affected. The homozygous mutation was lethal with a median survival time around 14-15 days post fertilization. The causal mutation was located by positional cloning in the c-cbl gene, the human ortholog of which, c-CBL, is found frequently mutated in myeloproliferative neoplasms (MPN) or acute leukemia. Sequence analysis showed the mutation in LDD731 caused a histidine-to-tyrosine substitution of the amino acid codon 382 within the RING finger domain of c-Cbl. Moreover, the myeloproliferative phenotype in zebrafish seemed dependent on the Flt3 (fms-like tyrosine kinase 3) signaling, consistent with that observed in both mice and humans. Our study may shed new light on the pathogenesis of MPN and provide a useful in vivo vertebrate model of this syndrome for screening drugs.
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Affiliation(s)
- X Peng
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - M Dong
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - L Ma
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China.,Shanghai Center for Systems Biomedicine, Ministry of Education Key Laboratory of Systems Biomedicine, Shanghai Jiao Tong University, Shanghai, China
| | - X-E Jia
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - J Mao
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - C Jin
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Y Chen
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - L Gao
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - X Liu
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - K Ma
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - L Wang
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - T Du
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - Y Jin
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - Q Huang
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - K Li
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - L I Zon
- Stem Cell Program at Boston Children's Hospital, Hematology/Oncology Program at Children's Hospital and Dana Faber Cancer Institute, Harvard Medical School, Boston, MA, USA.,Howard Hughes Medical Institute, Boston, MA, USA
| | - T Liu
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China.,Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - M Deng
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Y Zhou
- Key Laboratory of Stem Cell Biology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences and Graduate University, Chinese Academy of Sciences & Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - X Xi
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
| | - Y Zhou
- Stem Cell Program at Boston Children's Hospital, Hematology/Oncology Program at Children's Hospital and Dana Faber Cancer Institute, Harvard Medical School, Boston, MA, USA
| | - S Chen
- State Key Laboratory for Medical Genomics, Shanghai Institute of Hematology, RuiJin Hospital, Shanghai Jiao Tong University (SJTU) School of Medicine, and Collaborative Innovation Center of Systems Biomedicine, SJTU, Shanghai, China
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27
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Martinelli S, Stellacci E, Pannone L, D'Agostino D, Consoli F, Lissewski C, Silvano M, Cencelli G, Lepri F, Maitz S, Pauli S, Rauch A, Zampino G, Selicorni A, Melançon S, Digilio MC, Gelb BD, De Luca A, Dallapiccola B, Zenker M, Tartaglia M. Molecular Diversity and Associated Phenotypic Spectrum of Germline CBL Mutations. Hum Mutat 2015; 36:787-96. [PMID: 25952305 DOI: 10.1002/humu.22809] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 04/30/2015] [Indexed: 01/11/2023]
Abstract
Noonan syndrome (NS) is a relatively common developmental disorder with a pleomorphic phenotype. Mutations causing NS alter genes encoding proteins involved in the RAS-MAPK pathway. We and others identified Casitas B-lineage lymphoma proto-oncogene (CBL), which encodes an E3-ubiquitin ligase acting as a tumor suppressor in myeloid malignancies, as a disease gene underlying a condition clinically related to NS. Here, we further explored the spectrum of germline CBL mutations and their associated phenotype. CBL mutation scanning performed on 349 affected subjects with features overlapping NS and no mutation in NS genes allowed the identification of five different variants with pathological significance. Among them, two splice-site changes, one in-frame deletion, and one missense mutation affected the RING domain and/or the adjacent linker region, overlapping cancer-associated defects. A novel nonsense mutation generating a v-Cbl-like protein able to enhance signal flow through RAS was also identified. Genotype-phenotype correlation analysis performed on available records indicated that germline CBL mutations cause a variable phenotype characterized by a relatively high frequency of neurological features, predisposition to juvenile myelomonocytic leukemia, and low prevalence of cardiac defects, reduced growth, and cryptorchidism. Finally, we excluded a major contribution of two additional members of the CBL family, CBLB and CBLC, to NS and related disorders.
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Affiliation(s)
- Simone Martinelli
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy
| | - Emilia Stellacci
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy
| | - Luca Pannone
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy.,Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Rome, Italy
| | - Daniela D'Agostino
- Department of Medical Genetics, McGill University Health Centre, Montreal Children's Hospital, Montreal, Quebec, Canada
| | - Federica Consoli
- Dipartimento di Medicina Sperimentale, Sapienza Università di Roma, Rome, Italy.,Laboratorio Mendel, Istituto di Ricovero e Cura a Carattere Scientifico-Casa Sollievo della Sofferenza, Rome, Italy
| | - Christina Lissewski
- Institute of Human Genetics, University Hospital of Magdeburg, Otto-von-Guericke-University, Magdeburg, Germany
| | - Marianna Silvano
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy
| | - Giulia Cencelli
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy
| | | | - Silvia Maitz
- Dipartimento di Pediatria, Genetica Clinica, Ospedale S. Gerardo, Università di Milano-Bicocca, Monza, Italy
| | - Silke Pauli
- Institute of Human Genetics, University of Göttingen, Göttingen, Germany
| | - Anita Rauch
- Institute of Medical Genetics, University of Zurich, Schlieren-Zurich, Switzerland
| | - Giuseppe Zampino
- Istituto di Clinica Pediatrica, Università Cattolica del Sacro Cuore, Rome, Italy
| | - Angelo Selicorni
- Dipartimento di Pediatria, Genetica Clinica, Ospedale S. Gerardo, Università di Milano-Bicocca, Monza, Italy
| | - Serge Melançon
- Department of Medical Genetics, McGill University Health Centre, Montreal Children's Hospital, Montreal, Quebec, Canada
| | | | - Bruce D Gelb
- Mindich Child Health and Development Institute and Departments of Pediatrics and Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York
| | - Alessandro De Luca
- Laboratorio Mendel, Istituto di Ricovero e Cura a Carattere Scientifico-Casa Sollievo della Sofferenza, Rome, Italy
| | | | - Martin Zenker
- Institute of Human Genetics, University Hospital of Magdeburg, Otto-von-Guericke-University, Magdeburg, Germany
| | - Marco Tartaglia
- Dipartimento di Ematologia, Oncologia e Medicina Molecolare, Istituto Superiore di Sanità, Rome, Italy
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28
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Liyasova MS, Ma K, Lipkowitz S. Molecular pathways: cbl proteins in tumorigenesis and antitumor immunity-opportunities for cancer treatment. Clin Cancer Res 2015; 21:1789-94. [PMID: 25477533 PMCID: PMC4401614 DOI: 10.1158/1078-0432.ccr-13-2490] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 11/05/2014] [Indexed: 11/16/2022]
Abstract
The Cbl proteins are a family of ubiquitin ligases (E3s) that regulate signaling through many tyrosine kinase-dependent pathways. A predominant function is to negatively regulate receptor tyrosine kinase (RTK) signaling by ubiquitination of active RTKs, targeting them for trafficking to the lysosome for degradation. Also, Cbl-mediated ubiquitination can regulate signaling protein function by altered cellular localization of proteins without degradation. In addition to their role as E3s, Cbl proteins play a positive role in signaling by acting as adaptor proteins that can recruit signaling molecules to the active RTKs. Cbl-b, a second family member, negatively regulates the costimulatory pathway of CD8 T cells and also negatively regulates natural killer cell function. The different functions of Cbl proteins and their roles both in the development of cancer and the regulation of immune responses provide multiple therapeutic opportunities. Mutations in Cbl that inactivate the negative E3 function while maintaining the positive adaptor function have been described in approximately 5% of myeloid neoplasms. An improved understanding of how the signaling pathways [e.g., Fms-like tyrosine kinase 3 (Flt3), PI3K, and signal transducer and activator of transcription (Stat)] are dysregulated by these mutations in Cbl has helped to identify potential targets for therapy of myeloid neoplasms. Conversely, the loss of Cbl-b leads to increased adaptive and innate antitumor immunity, suggesting that inhibiting Cbl-b may be a means to increase antitumor immunity across a wide variety of tumors. Thus, targeting the pathways regulated by Cbl proteins may provide attractive opportunities for treating cancer.
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Affiliation(s)
- Mariya S Liyasova
- Women's Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Ke Ma
- Women's Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland
| | - Stanley Lipkowitz
- Women's Malignancies Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland.
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29
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Seong MW, Park JH, Yoo HM, Yang SW, Oh KH, Ka SH, Park DE, Lee ST, Chung CH. c-Cbl regulates αPix-mediated cell migration and invasion. Biochem Biophys Res Commun 2014; 455:153-8. [PMID: 25450678 DOI: 10.1016/j.bbrc.2014.10.129] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2014] [Accepted: 10/27/2014] [Indexed: 12/23/2022]
Abstract
c-Cbl, a RING-type ubiquitin E3 ligase, down-regulates receptor tyrosine kinases, including EGF receptor, and inhibits cell proliferation. Moreover, c-Cbl mutations are frequently found in patients with myeloid neoplasm. Therefore, c-Cbl is known as a tumor suppressor. αPix is expressed only in highly proliferative and mobile cells, including immune cells, and up-regulated in certain invasive tumors, such as glioblastoma multiforme. Here, we showed that c-Cbl serves as an ubiquitin E3 ligase for proteasome-mediated degradation of αPix, but not βPix. Remarkably, the rat C6 and human A172 glioma cells were unable to express c-Cbl, which leads to a dramatic accumulation of αPix. Depletion of αPix by shRNA markedly reduced the ability of the glioma cells to migrate and invade, whereas complementation of shRNA-insensitive αPix promoted it. These results indicate that c-Cbl negatively regulates αPix-mediated cell migration and invasion and the lack of c-Cbl in the C6 and A172 glioma cells is responsible for their malignant behavior.
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Affiliation(s)
- Min Woo Seong
- School of Biological Sciences and Institute for Protein Metabolism, Seoul National University, Seoul 151-742, Republic of Korea
| | - Ji Ho Park
- School of Biological Sciences and Institute for Protein Metabolism, Seoul National University, Seoul 151-742, Republic of Korea
| | - Hee Min Yoo
- School of Biological Sciences and Institute for Protein Metabolism, Seoul National University, Seoul 151-742, Republic of Korea
| | - Seung Wook Yang
- School of Biological Sciences and Institute for Protein Metabolism, Seoul National University, Seoul 151-742, Republic of Korea
| | - Kyu Hee Oh
- School of Biological Sciences and Institute for Protein Metabolism, Seoul National University, Seoul 151-742, Republic of Korea
| | - Seung Hyeun Ka
- School of Biological Sciences and Institute for Protein Metabolism, Seoul National University, Seoul 151-742, Republic of Korea
| | - Dong Eun Park
- School of Biological Sciences and Institute for Protein Metabolism, Seoul National University, Seoul 151-742, Republic of Korea
| | - Soon-Tae Lee
- Department of Neurology, Seoul National University Hospital, Seoul 110-744, Republic of Korea
| | - Chin Ha Chung
- School of Biological Sciences and Institute for Protein Metabolism, Seoul National University, Seoul 151-742, Republic of Korea.
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30
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Kang B, Sun XH. Regulation of cancer stem cells by RING finger ubiquitin ligases. Stem Cell Investig 2014; 1:5. [PMID: 27358852 DOI: 10.3978/j.issn.2306-9759.2014.01.01] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 01/16/2014] [Indexed: 01/03/2023]
Abstract
Like normal stem cells, cancer stem cells (CSCs) are capable of self-renewal, either by symmetric or asymmetric cell division. They have the exclusive ability to reproduce malignant tumors indefinitely, and to confer resistance in response to radiation or chemotherapy. The ubiquitin modification system plays various roles in physiology and pathology. The key component for the specificity of this system is ubiquitin ligases (E3s). Of these E3s, the majority are RING finger proteins. Many RING finger E3s, such as the Cullin1-Skp1-F-box protein (SCF) E3s, CBL, BRCA1, MDM2 and von Hippel-Lindau tumour suppressor (VHL), are crucial in the regulation of cell-cycle progression and cell differentiation. As a result, many RING finger E3s are implicated in the positive and negative regulation of CSC maintenance. This review summarizes current knowledge in this research field.
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Affiliation(s)
- Bin Kang
- Program in Immunobiology and Cancer Research, Oklahoma Medical Research Foundation, Oklahoma, USA
| | - Xiao-Hong Sun
- Program in Immunobiology and Cancer Research, Oklahoma Medical Research Foundation, Oklahoma, USA
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31
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Abstract
We describe the development of acute myeloid leukemia (AML) in an adult with CBL syndrome caused by a heterozygous de novo germline mutation in CBL codon D390. In the AML bone marrow, the mutated CBL allele was homozygous after copy number-neutral loss-of-heterozygosity and amplified through a chromosomal gain; moreover, an inv(16)(p13q22) and, as assessed by whole-exome sequencing, 12 gene mutations (eg, in CAND1, NID2, PTPRT, DOCK6) were additionally acquired. During complete remission of the AML, in the presence of normal blood counts, the hematopoiesis stably maintained the homozygous CBL mutation, which is reminiscent of the situation in children with CBL syndrome and transient juvenile myelomonocytic leukemia. No additional mutations were identified by whole-exome sequencing in granulocytes during complete remission. The study highlights the development of AML in an adult with CBL syndrome and, more generally, in genetically aberrant but clinically inconspicuous hematopoiesis.
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32
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33
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Lee H, Tsygankov AY. Cbl-family proteins as regulators of cytoskeleton-dependent phenomena. J Cell Physiol 2013; 228:2285-93. [DOI: 10.1002/jcp.24412] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Accepted: 05/29/2013] [Indexed: 12/21/2022]
Affiliation(s)
- Hojin Lee
- Department of Microbiology and Immunology; Sol Sherry Thrombosis Research Center and Fels Institute for Cancer Research; Temple University School of Medicine; Philadelphia Pennsylvania
| | - Alexander Y. Tsygankov
- Department of Microbiology and Immunology; Sol Sherry Thrombosis Research Center and Fels Institute for Cancer Research; Temple University School of Medicine; Philadelphia Pennsylvania
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34
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Abstract
The t(8;21) and inv(16)/t(16;16) rearrangements affecting the core-binding factors RUNX1 and CBFB, respectively, are found in 15% to 20% of adult de novo acute myeloid leukemia (AML) cases and are associated with a favorable prognosis. Since the expression of the fusion genes CBFB/MYH11 or RUNX1/RUNX1T1 alone is not sufficient to cause leukemia, we performed exome sequencing of an AML sample with an inv(16) to identify mutations, which may collaborate with the CBFB/MYH11 fusion during leukemogenesis. We discovered an N676K mutation in the adenosine triphosphate (ATP)-binding domain (tyrosine kinase domain 1 [TKD1]) of the fms-related tyrosine kinase 3 (FLT3) gene. In a cohort of 84 de novo AML patients with a CBFB/MYH11 rearrangement and in 36 patients with a RUNX1/RUNX1T1 rearrangement, the FLT3 N676K mutation was identified in 5 and 1 patients, respectively (5 [6%] of 84; 1 [3%] of 36). The FLT3-N676K mutant alone leads to factor-independent growth in Ba/F3 cells and, together with a concurrent FLT3-ITD (internal tandem duplication), confers resistance to the FLT3 protein tyrosine kinase inhibitors (PTKIs) PKC412 and AC220. Gene expression analysis of AML patients with CBFB/MYH11 rearrangement and FLT3 N676K mutation showed a trend toward a specific expression profile. Ours is the first report of recurring FLT3 N676 mutations in core-binding factor (CBF) leukemias and suggests a defined subgroup of CBF leukemias.
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35
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In hematopoietic cells with a germline mutation of CBL, loss of heterozygosity is not a signature of juvenile myelo-monocytic leukemia. Leukemia 2013; 27:2404-7. [PMID: 23823657 DOI: 10.1038/leu.2013.203] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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36
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Allen C, Hills RK, Lamb K, Evans C, Tinsley S, Sellar R, O'Brien M, Yin JL, Burnett AK, Linch DC, Gale RE. The importance of relative mutant level for evaluating impact on outcome of KIT, FLT3 and CBL mutations in core-binding factor acute myeloid leukemia. Leukemia 2013; 27:1891-901. [DOI: 10.1038/leu.2013.186] [Citation(s) in RCA: 108] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2013] [Revised: 05/24/2013] [Accepted: 06/14/2013] [Indexed: 12/25/2022]
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37
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Javadi M, Richmond TD, Huang K, Barber DL. CBL linker region and RING finger mutations lead to enhanced granulocyte-macrophage colony-stimulating factor (GM-CSF) signaling via elevated levels of JAK2 and LYN. J Biol Chem 2013; 288:19459-70. [PMID: 23696637 DOI: 10.1074/jbc.m113.475087] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023] Open
Abstract
Juvenile myelomonocytic leukemia (JMML) is characterized by hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF). SHP2, NF-1, KRAS, and NRAS are mutated in JMML patients, leading to aberrant regulation of RAS signaling. A subset of JMML patients harbor CBL mutations associated with 11q acquired uniparental disomy. Many of these mutations are in the linker region and the RING finger of CBL, leading to a loss of E3 ligase activity. We investigated the mechanism by which CBL-Y371H, a linker region mutant, and CBL-C384R, a RING finger mutant, lead to enhanced GM-CSF signaling. Expression of CBL mutants in the TF-1 cell line resulted in enhanced survival in the absence of GM-CSF. Cells expressing CBL mutations displayed increased phosphorylation of GM-CSF receptor βc subunit in response to stimulation, although expression of total GM-CSFR βc was lower. This suggested enhanced kinase activity downstream of GM-CSFR. JAK2 and LYN kinase expression is elevated in CBL-Y371H and CBL-C384R mutant cells, resulting in enhanced phosphorylation of CBL and S6 in response to GM-CSF stimulation. Incubation with the JAK2 inhibitor, TG101348, abolished the increased phosphorylation of GM-CSFR βc in cells expressing CBL mutants, whereas treatment with the SRC kinase inhibitor dasatinib resulted in equalization of GM-CSFR βc phosphorylation signal between wild type CBL and CBL mutant samples. Dasatinib treatment inhibited the elevated phosphorylation of CBL-Y371H and CBL-C384R mutants. Our study indicates that CBL linker and RING finger mutants lead to enhanced GM-CSF signaling due to elevated kinase expression, which can be blocked using small molecule inhibitors targeting specific downstream pathways.
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Affiliation(s)
- Mojib Javadi
- Ontario Cancer Institute, Campbell Family Cancer Research Institute, Toronto, Ontario M5G 2M9, Canada
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38
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Patnaik MM, Lasho TL, Finke CM, Hanson CA, Hodnefield JM, Knudson RA, Ketterling RP, Pardanani A, Tefferi A. Spliceosome mutations involving SRSF2, SF3B1, and U2AF35 in chronic myelomonocytic leukemia: prevalence, clinical correlates, and prognostic relevance. Am J Hematol 2013; 88:201-6. [PMID: 23335386 DOI: 10.1002/ajh.23373] [Citation(s) in RCA: 123] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 11/22/2012] [Accepted: 11/26/2012] [Indexed: 01/19/2023]
Abstract
SRSF2, SF3B1, and U2AF35 (U2AF1) are the three most frequent genes involved with spliceosome mutations in myeloid malignancies. SF3B1 mutations are most frequent (~80%) in myelodysplastic syndromes (MDS) with ring sideroblasts (RS) but lack prognostic relevance. SRSF2 mutations are associated with shortened overall (OS) and leukemia-free survival (LFS) in both MDS and myelofibrosis. In this study of 226 patients with chronic myelomonocytic leukemia (CMML), mutational frequencies were 40% for SRSF2 (all affecting P95), 6% for SF3B1 (primarily K700E) and 9% for U2AF35 (mostly S34F and Q157P/R). These mutations were mutually exclusive and 54% of the patients displayed at least one mutation. The three mutation groups were phenotypically similar, with the exception of higher RS% (P < 0.0001) in patients with SF3B1 mutations. At a median follow-up of 15 months, 176 (78%) deaths and 32 (14%) leukemic transformations were documented. OS (median survivals of 17, 16, 17, and 20 months; P = 0.48) and LFS (leukemic transformation rates of 17, 13, 15, and 5%; P = 0.63) were similar among patients with none of the three mutations, SRSF2, SF3B1, or U2AF35 mutations, respectively. We conclude that SRSF2 is the most frequently mutated spliceosome gene in CMML but neither it nor SF3B1 or U2AF35 mutations are prognostically relevant.
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Affiliation(s)
- Mrinal M Patnaik
- Division of Hematology, Mayo Clinic, Rochester, Minnesota 55905, USA
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39
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Schmitt-Graeff AH, Müller MJ, Fisch P. [Myelodysplastic syndromes. Epidemiology, molecular and morphological characteristics and risk stratification]. DER PATHOLOGE 2013; 34:45-55. [PMID: 23322304 DOI: 10.1007/s00292-012-1707-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Myelodysplastic syndromes (MDS) comprise a spectrum of clonal stem cell disorders which are currently defined according to the classification scheme of the revised 2008 WHO classification but which may be further refined in the future. The clinical presentation is often characterized by unexplained isolated or multiple peripheral blood cytopenias resulting in anemia, bleeding events or increased susceptibility to infections. The generally hypercellular, but rarely hypocellular and occasionally fibrotic bone marrow shows dysplastic features in ≥ 10 % of cells of at least one of the hematopoietic lineages. These features and enhanced apoptosis, stem cell senescence and immunologic dysregulation result in ineffective hematopoiesis. Diagnostics in MDS relies on complementary consideration of hematological, morphological and cytogenetic/molecular parameters. Methods include marrow and peripheral blood cytology, cytogenetics, fluorescence in situ hybridization (FISH), trephine bone marrow biopsy examination, immunophenotyping and the evaluation of molecular markers by established and new techniques. Mutations affecting growth factor receptors, cell cycle and apoptosis regulators, intracellular signaling, transcription factors, epigenetic regulation and the splicosome are involved in MDS pathogenesis and progression.
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Affiliation(s)
- A H Schmitt-Graeff
- Institut für Pathologie, Universitätsklinikum Freiburg, Breisacherstr. 115a, 79106, Freiburg, Deutschland.
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40
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Nadeau S, An W, Palermo N, Feng D, Ahmad G, Dong L, Borgstahl GEO, Natarajan A, Naramura M, Band V, Band H. Oncogenic Signaling by Leukemia-Associated Mutant Cbl Proteins. ACTA ACUST UNITED AC 2013; Suppl 6. [PMID: 23997989 DOI: 10.4172/2161-1009.s6-001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Members of the Cbl protein family (Cbl, Cbl-b, and Cbl-c) are E3 ubiquitin ligases that have emerged as critical negative regulators of protein tyrosine kinase (PTK) signaling. This function reflects their ability to directly interact with activated PTKs and to target them as well as their associated signaling components for ubiquitination. Given the critical roles of PTK signaling in driving oncogenesis, recent studies in animal models and genetic analyses in human cancer have firmly established that Cbl proteins function as tumor suppressors. Missense mutations or small in-frame deletions within the regions of Cbl protein that are essential for its E3 activity have been identified in nearly 5% of leukemia patients with myelodysplastic/myeloproliferative disorders. Based on evidence from cell culture studies, in vivo models and clinical data, we discuss the potential signaling mechanisms of mutant Cbl-driven oncogenesis. Mechanistic insights into oncogenic Cbl mutants and associated animal models are likely to enhance our understanding of normal hematopoietic stem cell homeostasis and provide avenues for targeted therapy of mutant Cbl-driven cancers.
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Affiliation(s)
- Scott Nadeau
- Eppley Institute for Research in Cancer and Allied Diseases, University of Nebraska Medical Center, 985950 Nebraska Medical Center Omaha, NE 68198-5950, USA ; Departments of Genetics, Cell Biology & Anatomy, University of Nebraska Medical Center, 985950 Nebraska Medical Center Omaha, NE 68198-5950, USA
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41
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Kazi JU, Rönnstrand L. Src-Like adaptor protein (SLAP) binds to the receptor tyrosine kinase Flt3 and modulates receptor stability and downstream signaling. PLoS One 2012; 7:e53509. [PMID: 23300935 PMCID: PMC3534055 DOI: 10.1371/journal.pone.0053509] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2012] [Accepted: 11/29/2012] [Indexed: 12/23/2022] Open
Abstract
Fms-like tyrosine kinase 3 (Flt3) is an important growth factor receptor in hematopoiesis. Gain-of-function mutations of the receptor contribute to the transformation of acute myeloid leukemia (AML). Src-like adaptor protein (SLAP) is an interaction partner of the E3 ubiquitin ligase Cbl that can regulate receptor tyrosine kinases-mediated signal transduction. In this study, we analyzed the role of SLAP in signal transduction downstream of the type III receptor tyrosine kinase Flt3. The results show that upon ligand stimulation SLAP stably associates with Flt3 through multiple phosphotyrosine residues in Flt3. SLAP constitutively interacts with oncogenic Flt3-ITD and co-localizes with Flt3 near the cell membrane. This association initiates Cbl-dependent receptor ubiquitination and degradation. Depletion of SLAP expression by shRNA in Flt3-transfected Ba/F3 cells resulted in a weaker activation of FL-induced PI3K-Akt and MAPK signaling. Meta-analysis of microarray data from patient samples suggests that SLAP mRNA is differentially expressed in different cancers and its expression was significantly increased in patients carrying the Flt3-ITD mutation. Thus, our data suggest a novel role of SLAP in different cancers and in modulation of receptor tyrosine kinase signaling apart from its conventional role in regulation of receptor stability.
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Affiliation(s)
- Julhash U. Kazi
- Experimental Clinical Chemistry, Wallenberg Laboratory, Department of Laboratory Medicine, Lund University, Skåne University Hospital, Malmö, Sweden
| | - Lars Rönnstrand
- Experimental Clinical Chemistry, Wallenberg Laboratory, Department of Laboratory Medicine, Lund University, Skåne University Hospital, Malmö, Sweden
- * E-mail:
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Milosevic JD, Kralovics R. Genetic and epigenetic alterations of myeloproliferative disorders. Int J Hematol 2012; 97:183-97. [PMID: 23233154 DOI: 10.1007/s12185-012-1235-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 11/27/2012] [Accepted: 11/27/2012] [Indexed: 01/07/2023]
Abstract
The classical BCR-ABL negative myeloproliferative neoplasms (MPN) polycythemia vera, essential thrombocythemia, and primary myelofibrosis are clonal hematopoietic disorders characterized by excessive production of terminally differentiated myeloid cells. In MPN patients, the disease can progress to secondary myelofibrosis or acute myeloid leukemia. Clonal hematopoiesis, disease phenotype, and progression are caused by somatically acquired genetic lesions of genes involved in cytokine signaling, RNA splicing, as well as epigenetic regulation. This review provides an overview of point mutations and cytogenetic lesions associated with MPN and addresses the role of these somatic lesions in MPN disease progression.
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Affiliation(s)
- Jelena D Milosevic
- CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Lazarettgasse 14, AKH BT25.3, 1090 Vienna, Austria
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FLT3 signals via the adapter protein Grb10 and overexpression of Grb10 leads to aberrant cell proliferation in acute myeloid leukemia. Mol Oncol 2012; 7:402-18. [PMID: 23246379 DOI: 10.1016/j.molonc.2012.11.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2012] [Accepted: 11/22/2012] [Indexed: 01/17/2023] Open
Abstract
The adaptor protein Grb10 plays important roles in mitogenic signaling. However, its roles in acute myeloid leukemia (AML) are predominantly unknown. Here we describe the role of Grb10 in FLT3-ITD-mediated AML. We observed that Grb10 physically associates with FLT3 in response to FLT3-ligand (FL) stimulation through FLT3 phospho-tyrosine 572 and 793 residues and constitutively associates with oncogenic FLT3-ITD. Furthermore endogenous Grb10-FLT3 association was observed in OCI-AML-5 cells. Grb10 expression did not alter FLT3 receptor activation or stability in Ba/F3-FLT3 cells. However, expression of Grb10 enhanced FL-induced Akt phosphorylation without affecting Erk or p38 phosphorylation in Ba/F3-FLT3-WT and Ba/F3-FLT3-ITD. Selective Grb10 depletion reduced Akt phosphorylation in Ba/F3-FLT3-WT and OCI-AML-5 cells. Grb10 transduces signal from FLT3 by direct interaction with p85 and Ba/F3-FLT3-ITD cells expressing Grb10 exhibits higher STAT5 activation. Grb10 regulates the cell cycle by increasing cell population in S-phase. Expression of Grb10 furthermore resulted in an increased proliferation and survival of Ba/F3-FLT3-ITD cells as well as increased colony formation in semisolid culture. Grb10 expression was significantly increased in AML patients compared to healthy controls and was also elevated in patients carrying FLT3-ITD mutants. The elevated Grb10 expression partially correlated to relapse as well as to poor prognosis. These results suggest that Grb10 binds to both normal and oncogenic FLT3 and induces PI3K-Akt and STAT5 signaling pathways resulting in an enhanced proliferation, survival and colony formation of hematopoietic cells.
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Flt3 inhibitor AC220 is a potent therapy in a mouse model of myeloproliferative disease driven by enhanced wild-type Flt3 signaling. Blood 2012; 120:4049-57. [DOI: 10.1182/blood-2012-06-436675] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Abstract
High levels of expression of wild-type Flt3 characterize many hematopoietic proliferative diseases and neoplasms, providing a potential therapeutic target. Using the c-Cbl RING finger mutant mouse as a model of a myeloproliferative disease (MPD) driven by wild-type Flt3, in the present study, we show that treatment with the Flt3 kinase inhibitor AC220 blocks MPD development by targeting Flt3+ multipotent progenitors (MPPs). We found that daily administration of AC220 caused a marked reduction in Flt3 expression, induction of quiescence, and a significant loss of MPPs within 4 days. Unexpectedly, a robust Flt3 ligand–associated proliferative recovery response soon followed, preventing further loss of MPPs. However, continued AC220 treatment limited MPP recovery and maintained reduced, steady-state levels of cycling MPPs that express low levels of Flt3. Therefore, a finely tuned balance between the opposing forces of AC220 and Flt3 ligand production was established; whereas the Flt3 ligand blunted the inhibitory effects of AC220, the disease was held in remission for as long as therapy was continued. The net effect is a potent therapy indicating that patients with c-Cbl mutations, or those with similarly enhanced Flt3 signaling, may respond well to AC220 even after the induction of high levels of Flt3 ligand.
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45
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Polzer H, Janke H, Schmid D, Hiddemann W, Spiekermann K. Casitas B-lineage lymphoma mutants activate AKT to induce transformation in cooperation with class III receptor tyrosine kinases. Exp Hematol 2012; 41:271-80.e4. [PMID: 23127761 DOI: 10.1016/j.exphem.2012.10.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2012] [Revised: 10/05/2012] [Accepted: 10/26/2012] [Indexed: 02/04/2023]
Abstract
In addition to overexpression and the occurrence of activating mutations, receptors can be aberrantly activated by impaired downregulation. In this study, we show that an oncogenic mutant of the ubiquitin ligase casitas B-lineage lymphoma (CBL; CBLΔexon8), which is found in acute myeloid leukemia patients, predominantly cooperates with receptor tyrosine kinase (RTK) class III receptors (PDGFRA, PDGFRB, KIT, and FLT3), but not with non-class III RTKs or cytokine receptors, to induce IL-3-independent growth of Ba/F3 cells. In cells coexpressing RTK class III/CBLΔexon8, receptor internalization was delayed, and cells were protected from apoptosis after cytokine withdrawal. Ligand-stimulated Ba/F3 cells and acute myeloid leukemia cell lines coexpressing the CBL deletion mutant and FLT3 showed enhanced AKT phosphorylation. Combined pharmacologic inhibition of the PI3K/AKT pathway and FLT3 had an additive effect on cell proliferation. The transforming potential of the CBL mutant was completely abolished by the mutation of the CBL PTB domain and was decreased by the mutation of tyrosines 589 and 591 in the juxtamembrane domain of FLT3. A constitutively active AKT1 mutant (E17K) recapitulated the phenotype induced by the CBL deletion mutant in Ba/F3 cells. This study reveals FLT3-CBL interaction sites and the AKT pathway as critical mediators of transformation by oncogenic CBL mutants.
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Affiliation(s)
- Harald Polzer
- Department of Internal Medicine III, University Hospital Grosshadern, Ludwig-Maximilians University, Munich, Germany
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46
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Campregher PV, Santos FPDS, Perini GF, Hamerschlak N. Molecular biology of Philadelphia-negative myeloproliferative neoplasms. Rev Bras Hematol Hemoter 2012; 34:150-5. [PMID: 23049405 PMCID: PMC3459398 DOI: 10.5581/1516-8484.20120035] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 12/21/2011] [Indexed: 01/13/2023] Open
Abstract
Myeloproliferative neoplasms are clonal diseases of hematopoietic stem cells characterized by myeloid hyperplasia and increased risk of developing acute myeloid leukemia. Myeloproliferative neoplasms are caused, as any other malignancy, by genetic defects that culminate in the neoplastic phenotype. In the past six years, since the identification of JAK2V617F, we have experienced a substantial increase in our knowledge about the genetic mechanisms involved in the genesis of myeloproliferative neoplasms. Mutations described in several genes have revealed a considerable degree of molecular homogeneity between different subtypes of myeloproliferative neoplasms. At the same time, the molecular differences between each subtype have become clearer. While mutations in several genes, such as JAK2, myeloproliferative leukemia (MPL) and LNK have been validated in functional assays or animal models as causative mutations, the roles of other recurring mutations in the development of disease, such as TET2 and ASXL1 remain to be elucidated. In this review we will examine the most prevalent recurring gene mutations found in myeloproliferative neoplasms and their molecular consequences.
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47
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Kazi JU, Sun J, Phung B, Zadjali F, Flores-Morales A, Rönnstrand L. Suppressor of cytokine signaling 6 (SOCS6) negatively regulates Flt3 signal transduction through direct binding to phosphorylated tyrosines 591 and 919 of Flt3. J Biol Chem 2012; 287:36509-17. [PMID: 22952242 DOI: 10.1074/jbc.m112.376111] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
The receptor tyrosine kinase Flt3 is an important growth factor receptor in hematopoiesis, and gain-of-function mutations of the receptor contribute to the transformation of acute myeloid leukemia. SOCS6 (suppressor of cytokine signaling 6) is a member of the SOCS family of E3 ubiquitin ligases that can regulate receptor tyrosine kinase signal transduction. In this study, we analyzed the role of SOCS6 in Flt3 signal transduction. The results show that ligand stimulation of Flt3 can induce association of SOCS6 and Flt3 and tyrosine phosphorylation of SOCS6. Phosphopeptide fishing indicated that SOCS6 binds directly to phosphotyrosines 591 and 919 of Flt3. By using stably transfected Ba/F3 cells with Flt3 and/or SOCS6, we show that the presence of SOCS6 can enhance ubiquitination of Flt3, as well as internalization and degradation of the receptor. The presence of SOCS6 also induces weaker activation of Erk1/2, but not Akt, in transfected Ba/F3 and UT-7 cells and in OCI-AML-5 cells. The absence of SOCS6 promotes Ba/F3 and UT-7 cell proliferation induced by oncogenic internal tandem duplications of Flt3. Taken together, these results suggest that SOCS6 negatively regulates Flt3 activation, the downstream Erk signaling pathway, and cell proliferation.
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Affiliation(s)
- Julhash U Kazi
- Experimental Clinical Chemistry, Department of Laboratory Medicine, Lund University, Wallenberg Laboratory, Skåne University Hospital, 20502 Malmö, Sweden
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48
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Lindsley RC, Ebert BL. Molecular pathophysiology of myelodysplastic syndromes. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2012; 8:21-47. [PMID: 22934674 DOI: 10.1146/annurev-pathol-011811-132436] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The clinicopathologic heterogeneity of myelodysplastic syndromes (MDS) is driven by diverse, somatically acquired genetic abnormalities. Recent technological advances have enabled the identification of many new mutations, which have implicated novel pathways in MDS pathogenesis, including RNA splicing and epigenetic regulation of gene expression. Molecular abnormalities, either somatic point mutations or chromosomal lesions, can be identified in the vast majority of MDS cases and underlie specific disease phenotypes. As the full array of molecular abnormalities is characterized, genetic variables are likely to complement standard morphologic evaluation in future MDS classification schemes and risk models.
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Affiliation(s)
- R Coleman Lindsley
- Division of Hematology, Brigham and Women's Hospital, Boston, MA 02215, USA
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49
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Ibáñez M, Such E, Cervera J, Luna I, Gómez-Seguí I, López-Pavía M, Dolz S, Barragán E, Fuster O, Llop M, Rodríguez-Veiga R, Avaria A, Oltra S, Senent ML, Moscardó F, Montesinos P, Martínez-Cuadrón D, Martín G, Sanz MA. Rapid screening of ASXL1, IDH1, IDH2, and c-CBL mutations in de novo acute myeloid leukemia by high-resolution melting. J Mol Diagn 2012; 14:594-601. [PMID: 22929312 DOI: 10.1016/j.jmoldx.2012.06.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 05/08/2012] [Accepted: 06/08/2012] [Indexed: 11/16/2022] Open
Abstract
Recently, many novel molecular abnormalities were found to be distinctly associated with acute myeloid leukemia (AML). However, their clinical relevance and prognostic implications are not well established. We developed a new combination of high-resolution melting assays on a LightCycler 480 and direct sequencing to detect somatic mutations of ASXL1 (exon 12), IDH1 (exon 4), IDH2 (exon 4), and c-CBL (exons 8 and 9) genes to know their incidence and prognostic effect in a cohort of 175 patients with de novo AML: 16 patients (9%) carried ASXL1 mutations, 16 patients had IDH variations (3% with IDH1(R132) and 6% with IDH2(R140)), and none had c-CBL mutations. Patients with ASXL1 mutations did not harbor IDH1, [corrected] or CEBPA mutations, and a combination of ASXL1 and IDH2 mutations was found only in one patient. In addition, we did not find IDH1 and FLT3 or CEBPA mutations concurrently or IDH2 with CEBPA. IDH1 and IDH2 mutations were mutually exclusive. Alternatively, NPM1 mutations were concurrently found with ASXL1, IDH1, or IDH2 with a variable incidence. Mutations were not significantly correlated with any of the clinical and biological features studied. High-resolution melting is a reliable, rapid, and efficient screening technique for mutation detection in AML. The incidence for the studied genes was in the range of those previously reported. We were unable to find an effect on the outcome.
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Affiliation(s)
- Mariam Ibáñez
- Department of Hematology, University Hospital La Fe, Valencia, Spain.
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Abstract
We analyzed the mutational hotspot region of SRSF2 (Pro95) in 275 cases with chronic myelomonocytic leukemia (CMML). In addition, ASXL1, CBL, EZH2, JAK2V617F, KRAS, NRAS, RUNX1, and TET2 mutations were investigated in subcohorts. Mutations in SRSF2 (SRSF2mut) were detected in 47% (129 of 275) of all cases. In detail, 120 cases had a missense mutation at Pro95, leading to a change to Pro95His, Pro95Leu, Pro95Arg, Pro95Ala, or Pro95Thr. In 9 cases, 3 new in/del mutations were observed: 7 cases with a 24-bp deletion, 1 case with a 3-bp duplication, and 1 case with a 24-bp duplication. In silico analyses predicted a damaging character for the protein structure of SRSF2 for all mutations. SRSF2mut was correlated with higher age, less pronounced anemia, and normal karyotype. SRSF2mut and EZH2mut were mutually exclusive, but SRSF2mut was associated with TET2mut. In the total cohort, no effect of SRSF2mut on survival was observed. However, in the RUNX1mut subcohort, SRSF2 Pro95His had a favorable effect on overall survival. This comprehensive mutation analysis found that 93% of all patients with CMML carried at least 1 somatic mutation in 9 recurrently mutated genes. In conclusion, these data show the importance of SRSF2mut as new diagnostic marker in CMML.
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