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Gutierrez-Camino A, Richer C, Ouimet M, Fuchs C, Langlois S, Khater F, Caron M, Beaulieu P, St-Onge P, Bataille AR, Sinnett D. Characterisation of FLT3 alterations in childhood acute lymphoblastic leukaemia. Br J Cancer 2024; 130:317-326. [PMID: 38049555 PMCID: PMC10803556 DOI: 10.1038/s41416-023-02511-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 12/06/2023] Open
Abstract
BACKGROUND Alterations of FLT3 are among the most common driver events in acute leukaemia with important clinical implications, since it allows patient classification into prognostic groups and the possibility of personalising therapy thanks to the availability of FLT3 inhibitors. Most of the knowledge on FLT3 implications comes from the study of acute myeloid leukaemia and so far, few studies have been performed in other leukaemias. METHODS A comprehensive genomic (DNA-seq in 267 patients) and transcriptomic (RNA-seq in 160 patients) analysis of FLT3 in 342 childhood acute lymphoblastic leukaemia (ALL) patients was performed. Mutations were functionally characterised by in vitro experiments. RESULTS Point mutations (PM) and internal tandem duplications (ITD) were detected in 4.3% and 2.7% of the patients, respectively. A new activating mutation of the TKD, G846D, conferred oncogenic properties and sorafenib resistance. Moreover, a novel alteration involving the circularisation of read-through transcripts (rt-circRNAs) was observed in 10% of the cases. Patients presenting FLT3 alterations exhibited higher levels of the receptor. In addition, patients with ZNF384- and MLL/KMT2A-rearranged ALL, as well as hyperdiploid subtype, overexpressed FLT3. DISCUSSION Our results suggest that specific ALL subgroups may also benefit from a deeper understanding of the biology of FLT3 alterations and their clinical implications.
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Affiliation(s)
- Angela Gutierrez-Camino
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Chantal Richer
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Manon Ouimet
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Claire Fuchs
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Sylvie Langlois
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Fida Khater
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Maxime Caron
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Patrick Beaulieu
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Pascal St-Onge
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Alain R Bataille
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada
| | - Daniel Sinnett
- Division of Hematology-Oncology, CHU Sainte-Justine Research Center, Montreal, Quebec, Canada.
- Department of Pediatrics, Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada.
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Jang SH, Sivakumar D, Mudedla SK, Choi J, Lee S, Jeon M, Bvs SK, Hwang J, Kang M, Shin EG, Lee KM, Jung KY, Kim JS, Wu S. PCW-A1001, AI-assisted de novo design approach to design a selective inhibitor for FLT-3(D835Y) in acute myeloid leukemia. Front Mol Biosci 2022; 9:1072028. [PMID: 36504722 PMCID: PMC9732455 DOI: 10.3389/fmolb.2022.1072028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 11/16/2022] [Indexed: 11/27/2022] Open
Abstract
Treating acute myeloid leukemia (AML) by targeting FMS-like tyrosine kinase 3 (FLT-3) is considered an effective treatment strategy. By using AI-assisted hit optimization, we discovered a novel and highly selective compound with desired drug-like properties with which to target the FLT-3 (D835Y) mutant. In the current study, we applied an AI-assisted de novo design approach to identify a novel inhibitor of FLT-3 (D835Y). A recurrent neural network containing long short-term memory cells (LSTM) was implemented to generate potential candidates related to our in-house hit compound (PCW-1001). Approximately 10,416 hits were generated from 20 epochs, and the generated hits were further filtered using various toxicity and synthetic feasibility filters. Based on the docking and free energy ranking, the top compound was selected for synthesis and screening. Of these three compounds, PCW-A1001 proved to be highly selective for the FLT-3 (D835Y) mutant, with an IC50 of 764 nM, whereas the IC50 of FLT-3 WT was 2.54 μM.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Minsung Kang
- Division of Radiation Biomedical Research, Korea Institute of Radiological and Medical Sciences, Seoul, South Korea
| | - Eun Gyeong Shin
- Therapeutics & Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, South Korea,Department of Medicinal Chemistry and Pharmacology, University of Science & Technology, Daejeon, South Korea
| | - Kyu Myung Lee
- Therapeutics & Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, South Korea
| | - Kwan-Young Jung
- Therapeutics & Biotechnology Division, Korea Research Institute of Chemical Technology, Daejeon, South Korea,Department of Medicinal Chemistry and Pharmacology, University of Science & Technology, Daejeon, South Korea,*Correspondence: Kwan-Young Jung, ; Jae-Sung Kim, ; Sangwook Wu,
| | - Jae-Sung Kim
- Division of Radiation Biomedical Research, Korea Institute of Radiological and Medical Sciences, Seoul, South Korea,*Correspondence: Kwan-Young Jung, ; Jae-Sung Kim, ; Sangwook Wu,
| | - Sangwook Wu
- R&D Center, PharmCADD, Busan, South Korea,Department of Physics, Pukyong National University, Busan, South Korea,*Correspondence: Kwan-Young Jung, ; Jae-Sung Kim, ; Sangwook Wu,
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Genomic Abnormalities as Biomarkers and Therapeutic Targets in Acute Myeloid Leukemia. Cancers (Basel) 2021; 13:cancers13205055. [PMID: 34680203 PMCID: PMC8533805 DOI: 10.3390/cancers13205055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Revised: 10/01/2021] [Accepted: 10/08/2021] [Indexed: 11/17/2022] Open
Abstract
Simple Summary AML is a heterogenous malignancy with a variety of underlying genomic abnormalities. Some of the genetic aberrations in AML have led to the development of specific inhibitors which were approved by the Food and Drug Administration (FDA) and are currently used to treat eligible patients. In this review, we describe five gene mutations for which approved inhibitors have been developed, the response of AML patients to these inhibitors, and the known mechanism(s) of resistance. This review also highlights the significance of developing function-based screens for target discovery in the era of personalized medicine. Abstract Acute myeloid leukemia (AML) is a highly heterogeneous malignancy characterized by the clonal expansion of myeloid stem and progenitor cells in the bone marrow, peripheral blood, and other tissues. AML results from the acquisition of gene mutations or chromosomal abnormalities that induce proliferation or block differentiation of hematopoietic progenitors. A combination of cytogenetic profiling and gene mutation analyses are essential for the proper diagnosis, classification, prognosis, and treatment of AML. In the present review, we provide a summary of genomic abnormalities in AML that have emerged as both markers of disease and therapeutic targets. We discuss the abnormalities of RARA, FLT3, BCL2, IDH1, and IDH2, their significance as therapeutic targets in AML, and how various mechanisms cause resistance to the currently FDA-approved inhibitors. We also discuss the limitations of current genomic approaches for producing a comprehensive picture of the activated signaling pathways at diagnosis or at relapse in AML patients, and how innovative technologies combining genomic and functional methods will improve the discovery of novel therapeutic targets in AML. The ultimate goal is to optimize a personalized medicine approach for AML patients and possibly those with other types of cancers.
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Deletions in FLT-3 juxtamembrane domain define a new class of pathogenic mutations: case report and systematic analysis. Blood Adv 2021; 5:2285-2293. [PMID: 33914060 DOI: 10.1182/bloodadvances.2020002876] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 03/17/2021] [Indexed: 11/20/2022] Open
Abstract
The FMS-like tyrosine kinase 3 (FLT-3) is the most frequently mutated gene in acute myeloid leukemia (AML), a high-risk feature, and now the target of tyrosine kinase inhibitors (TKIs), which are approved and in development. The most common mutation is the internal tandem duplication (ITD). We present a novel mutation, FLT-3/Q575Δ, identified in a patient with AML through next-generation sequencing (NGS). This mutation is activating, drives downstream signaling comparable to FLT-3/ITD, and can be targeted using available FLT-3 TKIs. We present the results of a systematic analysis that identified Y572Δ, E573Δ, and S574Δ as similarly activating and targetable deletions located in the FLT-3 juxtamembrane domain (JMD). These mutations target key residues in the JMD involved in the interactions within FLT-3 that regulate its activation. Our results suggest a new class of FLT-3 mutations that may have an impact on patient care and highlight the increasing importance of a systematic understanding of FLT-3 mutations other than ITD. It is likely that, as NGS becomes more commonly used in the diagnosis of patients with AML, these and other activating mutations will be discovered with increasing frequency.
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Abstract
Aberrant FLT3 receptor signaling is common in acute myeloid leukemia (AML) and has important implications for the biology and clinical management of the disease. Patients with FLT3-mutated AML frequently present with critical illness, are more likely to relapse after treatment, and have worse clinical outcomes than their FLT3 wild type counterparts. The clinical management of FLT3-mutated AML has been transformed by the development of FLT3 inhibitors, which are now in use in the frontline and relapsed/refractory settings. However, many questions regarding the optimal approach to the treatment of these patients remain. In this paper, we will review the rationale for targeting the FLT3 receptor in AML, the impact of FLT3 mutation on patient prognosis, the current standard of care approaches to FLT3-mutated AML management, and the diverse array of FLT3 inhibitors in use and under investigation. We will also explore new opportunities and strategies for targeting the FLT3 receptor. These include targeting the receptor in patients with non-canonical FLT3 mutations or wild type FLT3, pairing FLT3 inhibitors with other novel therapies, using minimal residual disease (MRD) testing to guide the targeting of FLT3, and novel immunotherapeutic approaches.
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Affiliation(s)
- Alexander J Ambinder
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Mark Levis
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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Diagnostic and therapeutic pitfalls in NPM1-mutated AML: notes from the field. Leukemia 2021; 35:3113-3126. [PMID: 33879827 PMCID: PMC8056374 DOI: 10.1038/s41375-021-01222-4] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/21/2021] [Accepted: 03/09/2021] [Indexed: 02/02/2023]
Abstract
Mutations of Nucleophosmin (NPM1) are the most common genetic abnormalities in adult acute myeloid leukaemia (AML), accounting for about 30% of cases. NPM1-mutated AML has been recognized as distinct entity in the 2017 World Health Organization (WHO) classification of lympho-haematopoietic neoplasms. WHO criteria allow recognition of this leukaemia entity and its distinction from AML with myelodysplasia-related changes, AML with BCR-ABL1 rearrangement and AML with RUNX1 mutations. Nevertheless, controversial issues include the percentage of blasts required for the diagnosis of NPM1-mutated AML and whether cases of NPM1-mutated myelodysplasia and chronic myelomonocytic leukaemia do exist. Evaluation of NPM1 and FLT3 status represents a major pillar of the European LeukemiaNet (ELN) genetic-based risk stratification model. Moreover, NPM1 mutations are particularly suitable for assessing measurable residual disease (MRD) since they are frequent, stable at relapse and do not drive clonal haematopoiesis. Ideally, combining monitoring of MRD with the ELN prognostication model can help to guide therapeutic decisions. Here, we provide examples of instructive cases of NPM1-mutated AML, in order to provide criteria for the appropriate diagnosis and therapy of this frequent leukaemia entity.
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Marensi V, Keeshan KR, MacEwan DJ. Pharmacological impact of FLT3 mutations on receptor activity and responsiveness to tyrosine kinase inhibitors. Biochem Pharmacol 2020; 183:114348. [PMID: 33242449 DOI: 10.1016/j.bcp.2020.114348] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 11/19/2020] [Accepted: 11/19/2020] [Indexed: 01/09/2023]
Abstract
Acute myelogenous leukaemia (AML) is an aggressive blood cancer characterized by the rapid proliferation of immature myeloid blast cells, resulting in a high mortality rate. The 5-year overall survival rate for AML patients is approximately 25%. Circa 35% of all patients carry a mutation in the FLT3 gene which have a poor prognosis. Targeting FLT3 receptor tyrosine kinase has become a treatment strategy in AML patients possessing FLT3 mutations. The most common mutations are internal tandem duplications (ITD) within exon 14 and a single nucleotide polymorphism (SNP) that leads to a point mutation in the D835 of the tyrosine kinase domain (TKD). Variations in the ITD sequence and the occurrence of other point mutations that lead to ligand-independent FLT3 receptor activation create difficulties in developing personalized therapeutic strategies to overcome observed mutation-driven drug resistance. Midostaurin and quizartinib are tyrosine kinase inhibitors (TKIs) with inhibitory efficacy against FLT3-ITD, but exhibit limited clinical impact. In this review, we focus on the structural aspects of the FLT3 receptor and correlate those mutations with receptor activation and the consequences for molecular and clinical responsiveness towards therapies targeting FLT3-ITD positive AML.
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Affiliation(s)
- Vanessa Marensi
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom
| | - Karen R Keeshan
- Paul O'Gorman Leukaemia Research Centre, Institute of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - David J MacEwan
- Department of Pharmacology and Therapeutics, Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, United Kingdom.
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Borowczyk M, Szczepanek-Parulska E, Dębicki S, Budny B, Janicka-Jedyńska M, Gil L, Verburg FA, Filipowicz D, Wrotkowska E, Majchrzycka B, Marszałek A, Ziemnicka K, Ruchała M. High incidence of FLT3 mutations in follicular thyroid cancer: potential therapeutic target in patients with advanced disease stage. Ther Adv Med Oncol 2020; 12:1758835920907534. [PMID: 32180839 PMCID: PMC7057406 DOI: 10.1177/1758835920907534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 01/22/2020] [Indexed: 11/30/2022] Open
Abstract
Background: Conventional treatments for follicular thyroid cancer (FTC) can be ineffective, leading to poor prognosis. The aim of this study was to identify mutations associated with FTC that would serve as novel molecular markers of the disease and its outcome and could potentially identify new therapeutic targets. Methods: FLT3 mutations were first detected in a 29-year-old White female diagnosed with metastasized, treatment-refractory FTC. Analyses of FLT3 mutational status through next-generation sequencing of formalin-fixed, paraffin-embedded FTC specimens were subsequently performed in 35 randomly selected patients diagnosed with FTC. Results: FLT3 mutations were found in 69% of patients. FLT3 mutation-positive patients were significantly older than those that were FLT3 mutation-negative [median age at diagnosis 54 (36–82) versus 45 (27–58) (p = 0.023)]. Patients over 60 years were 23 times more likely to be FLT3 mutation-positive (p = 0.006). However, the number of FLT3 mutations did not correlate with age (r-Pearson: –0.244, p-value: 0.25). A total of 26 mutations were identified in the FLT3 gene with 2–16 FLT3 mutations in each FLT3 mutation-positive patient (mean: 5.6 mutations/patient). Tyrosine kinase domain (TKD) mutations in the FLT3 gene were detected in 58% of FLT3 mutation-positive patients. All FLT3 mutation-positive patients with a disease stage of pT2N1 or worse harbored at least one mutation in the TKD of FLT3. Conclusions: There is a wide spectrum and high frequency of FLT3 mutations in FTC. The precise role of FLT3 mutations in the genesis of FTC, as well as its potential role as a therapeutic target, requires further investigation.
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Affiliation(s)
- Martyna Borowczyk
- Department of Endocrinology, Metabolism and Internal Diseases, Poznań University of Medical Sciences, Przybyszewskiego Street, 49, Poznan, 60-355, Poland
| | - Ewelina Szczepanek-Parulska
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Szymon Dębicki
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Bartłomiej Budny
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | | | - Lidia Gil
- Department of Hematology and Bone Marrow Transplantation, Poznan University of Medical Sciences, Poznan, Poland
| | - Frederik A Verburg
- Department of Nuclear Medicine, University Hospital Marburg, Marburg, Germany
| | - Dorota Filipowicz
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Elżbieta Wrotkowska
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Blanka Majchrzycka
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Andrzej Marszałek
- Department of Oncologic Pathology and Prophylaxis, Poznan University of Medical Sciences, Poznan, Poland
| | - Katarzyna Ziemnicka
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
| | - Marek Ruchała
- Department of Endocrinology, Metabolism and Internal Diseases, Poznan University of Medical Sciences, Poznan, Poland
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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: 86] [Impact Index Per Article: 17.2] [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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Schittenhelm MM, Walter B, Tsintari V, Federmann B, Bajrami Saipi M, Akmut F, Illing B, Mau-Holzmann U, Fend F, Lopez CD, Kampa-Schittenhelm KM. Alternative splicing of the tumor suppressor ASPP2 results in a stress-inducible, oncogenic isoform prevalent in acute leukemia. EBioMedicine 2019; 42:340-351. [PMID: 30952616 PMCID: PMC6491939 DOI: 10.1016/j.ebiom.2019.03.028] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2019] [Revised: 03/10/2019] [Accepted: 03/11/2019] [Indexed: 01/01/2023] Open
Abstract
Background Apoptosis-stimulating Protein of TP53-2 (ASPP2) is a tumor suppressor enhancing TP53-mediated apoptosis via binding to the TP53 core domain. TP53 mutations found in cancers disrupt ASPP2 binding, arguing for an important role of ASPP2 in TP53-mediated tumor suppression. We now identify an oncogenic splicing variant, ASPP2κ, with high prevalence in acute leukemia. Methods An mRNA screen to detect ASPP2 splicing variants was performed and ASPP2κ was validated using isoform-specific PCR approaches. Translation into a genuine protein isoform was evaluated after establishing epitope-specific antibodies. For functional studies cell models with forced expression of ASPP2κ or isoform-specific ASPP2κ-interference were created to evaluate proliferative, apoptotic and oncogenic characteristics of ASPP2κ. Findings Exon skipping generates a premature stop codon, leading to a truncated C-terminus, omitting the TP53-binding sites. ASPP2κ translates into a dominant-negative protein variant impairing TP53-dependent induction of apoptosis. ASPP2κ is expressed in CD34+ leukemic progenitor cells and functional studies argue for a role in early oncogenesis, resulting in perturbed proliferation and impaired induction of apoptosis, mitotic failure and chromosomal instability (CIN) – similar to TP53 mutations. Importantly, as expression of ASPP2κ is stress-inducible it defines a novel class of dynamic oncogenes not represented by genomic mutations. Interpretation Our data demonstrates that ASPP2κ plays a distinctive role as an antiapoptotic regulator of the TP53 checkpoint, rendering cells to a more aggressive phenotype as evidenced by proliferation and apoptosis rates – and ASPP2κ expression results in acquisition of genomic mutations, a first initiating step in leukemogenesis. We provide proof-of-concept to establish ASPP2κ as a clinically relevant biomarker and a target for molecule-defined therapy. Fund Unrestricted grant support from the Wilhelm Sander Foundation for Cancer Research, the IZKF Program of the Medical Faculty Tübingen, the Brigitte Schlieben-Lange Program and the Margarete von Wrangell Program of the State Ministry Baden-Wuerttemberg for Science, Research and Arts and the Athene Program of the excellence initiative of the Eberhard-Karls University, Tübingen.
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Affiliation(s)
- Marcus Matthias Schittenhelm
- Department of Oncology, Hematology, Rheumatology, Immunology and Pulmology, University Hospital Tübingen, Germany
| | - Bianca Walter
- Department of Oncology, Hematology, Rheumatology, Immunology and Pulmology, University Hospital Tübingen, Germany
| | - Vasileia Tsintari
- Department of Oncology, Hematology, Rheumatology, Immunology and Pulmology, University Hospital Tübingen, Germany
| | - Birgit Federmann
- Institute of General and Molecular Pathology and Pathological Anatomy, University Hospital Tübingen, Germany
| | - Mihada Bajrami Saipi
- Department of Oncology, Hematology, Rheumatology, Immunology and Pulmology, University Hospital Tübingen, Germany
| | - Figen Akmut
- Department of Oncology, Hematology, Rheumatology, Immunology and Pulmology, University Hospital Tübingen, Germany
| | - Barbara Illing
- Department of Oncology, Hematology, Rheumatology, Immunology and Pulmology, University Hospital Tübingen, Germany
| | | | - Falko Fend
- Institute of General and Molecular Pathology and Pathological Anatomy, University Hospital Tübingen, Germany
| | - Charles Darin Lopez
- Department of Hematology and Medical Oncology, Oregon Health and Science University, Portland, OR, United States of America
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Klug LR, Kent JD, Heinrich MC. Structural and clinical consequences of activation loop mutations in class III receptor tyrosine kinases. Pharmacol Ther 2018; 191:123-134. [DOI: 10.1016/j.pharmthera.2018.06.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
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Crenolanib is a type I tyrosine kinase inhibitor that inhibits mutant KIT D816 isoforms prevalent in systemic mastocytosis and core binding factor leukemia. Oncotarget 2017; 8:82897-82909. [PMID: 29137311 PMCID: PMC5669937 DOI: 10.18632/oncotarget.19970] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2016] [Accepted: 07/20/2017] [Indexed: 12/29/2022] Open
Abstract
Activating D816 mutations of the class III receptor tyrosine kinase KIT are associated with the majority of patients with systemic mastocytosis (SM), but also core binding factor (CBF) AML, making KIT mutations attractive therapeutic targets for the treatment of these cancers. Crenolanib is a potent and selective inhibitor of wild-type as well as mutant isoforms of the class III receptor tyrosine kinases FLT3 and PDGFRα/β. Notably, crenolanib inhibits constitutively active mutant-FLT3 isoforms resulting from amino acid substitutions of aspartic acid at codon 835, which is homologous to codon 816 in the KIT gene - suggesting sensitivity against mutant-KIT D816 isoforms as well. Here we demonstrate that crenolanib targets KIT D816 in SM and CBF AML models: crenolanib inhibits cellular proliferation and initiates apoptosis of mastocytosis cell lines expressing these mutations. Target-specificity was confirmed using an isogenic cell model. In addition, we demonstrate that KIT D816 mutations are targetable with clinically achievable doses of crenolanib. Further, a rationale to combine cladribine (2-CDA), the therapeutic standard in SM, with crenolanib is provided. In conclusion, we demonstrate that crenolanib is an inhibitor of mutant-KIT D816 isoforms at clinically achievable concentrations, and thus may be a potential treatment for SM and CBF AML as a monotherapy or in combination approaches.
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Chen C, Bartenhagen C, Gombert M, Okpanyi V, Binder V, Röttgers S, Bradtke J, Teigler-Schlegel A, Harbott J, Ginzel S, Thiele R, Husemann P, Krell PF, Borkhardt A, Dugas M, Hu J, Fischer U. Next-generation-sequencing of recurrent childhood high hyperdiploid acute lymphoblastic leukemia reveals mutations typically associated with high risk patients. Leuk Res 2015; 39:990-1001. [DOI: 10.1016/j.leukres.2015.06.005] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 06/08/2015] [Accepted: 06/10/2015] [Indexed: 01/07/2023]
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14
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Diaz R, Nguewa PA, Redrado M, Manrique I, Calvo A. Sunitinib reduces tumor hypoxia and angiogenesis, and radiosensitizes prostate cancer stem-like cells. Prostate 2015; 75:1137-49. [PMID: 25893276 DOI: 10.1002/pros.22980] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 01/19/2015] [Indexed: 12/17/2022]
Abstract
INTRODUCTION The need for new treatments for advanced prostate cancer has fostered the experimental use of targeted therapies. Sunitinib is a multi-tyrosine kinase inhibitor that mainly targets membrane-bound receptors of cells within the tumor microenvironment, such as endothelial cells and pericytes. However, recent studies suggest a direct effect on tumor cells. In the present study, we have evaluated both direct and indirect effects of Sunitinib in prostate cancer and how this drug regulates hypoxia, using in vitro and in vivo models. METHODS We have used both in vitro (PC-3, DU145, and LNCaP cells) and in vivo (PC-3 xenografts) models to study the effect of Sunitinib in prostate cancer. Analysis of hypoxia based on HIF-1α expression and FMISO uptake was conducted. ALDH activity was used to analyze cancer stem cells (CSC). RESULTS Sunitinib strongly reduced proliferation of PC-3 and DU-145 cells in a dose dependent manner, and decreased levels of p-Akt, p-Erk1/2, and Id-1, compared to untreated cells. A 3-fold reduction in tumor growth was also observed (P < 0.001 with respect to controls). Depletion of Hif-1α levels in vitro and a decrease in FMISO uptake in vivo showed that Sunitinib inhibits tumor hypoxia. When combined with radiotherapy, this drug enhanced cell death in vitro and in vivo, and significantly decreased CD-31, PDGFRβ, Hif-1α, Id1, and PCNA protein levels (whereas apoptosis was increased) in tumors as compared to controls or single-therapy treated mice. Moreover, Sunitinib reduced the number of ALDH + cancer stem-like cells and sensitized these cells to radiation-mediated loss of clonogenicity. DISCUSION Our results support the use of Sunitinib in prostate cancer and shows that both hypoxia and cancer stem cells are involved in the effect elicited by this drug. Combination of Sunitinib with radiotherapy warrants further consideration to reduce prostate cancer burden.
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Affiliation(s)
- Roque Diaz
- Division of Oncology, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Paul A Nguewa
- Division of Oncology, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
- Department of Microbiology and Parasitology, Instituto de Salud Tropical, University of Navarra, Pamplona, Spain
| | - Miriam Redrado
- Division of Oncology, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Irene Manrique
- Division of Oncology, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
| | - Alfonso Calvo
- Division of Oncology, Center for Applied Medical Research (CIMA), University of Navarra, Pamplona, Spain
- Department of Histology and Pathology, University of Navarra, Pamplona, Spain
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Ke YY, Singh VK, Coumar MS, Hsu YC, Wang WC, Song JS, Chen CH, Lin WH, Wu SH, Hsu JTA, Shih C, Hsieh HP. Homology modeling of DFG-in FMS-like tyrosine kinase 3 (FLT3) and structure-based virtual screening for inhibitor identification. Sci Rep 2015; 5:11702. [PMID: 26118648 PMCID: PMC4483777 DOI: 10.1038/srep11702] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 06/02/2015] [Indexed: 12/23/2022] Open
Abstract
The inhibition of FMS-like tyrosine kinase 3 (FLT3) activity using small-molecule inhibitors has emerged as a target-based alternative to traditional chemotherapy for the treatment of acute myeloid leukemia (AML). In this study, we report the use of structure-based virtual screening (SBVS), a computer-aided drug design technique for the identification of new chemotypes for FLT3 inhibition. For this purpose, homology modeling (HM) of the DFG-in FLT3 structure was carried using two template structures, including PDB ID: 1RJB (DFG-out FLT3 kinase domain) and PDB ID: 3LCD (DFG-in CSF-1 kinase domain). The modeled structure was able to correctly identify known DFG-in (SU11248, CEP-701, and PKC-412) and DFG-out (sorafenib, ABT-869 and AC220) FLT3 inhibitors, in docking studies. The modeled structure was then used to carry out SBVS of an HTS library of 125,000 compounds. The top scoring 97 compounds were tested for FLT3 kinase inhibition, and two hits (BPR056, IC50 = 2.3 and BPR080, IC50 = 10.7 μM) were identified. Molecular dynamics simulation and density functional theory calculation suggest that BPR056 (MW: 325.32; cLogP: 2.48) interacted with FLT3 in a stable manner and could be chemically optimized to realize a drug-like lead in the future.
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Affiliation(s)
- Yi-Yu Ke
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Vivek Kumar Singh
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605014, India
| | - Mohane Selvaraj Coumar
- Centre for Bioinformatics, School of Life Sciences, Pondicherry University, Kalapet, Puducherry 605014, India
| | - Yung Chang Hsu
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Wen-Chieh Wang
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Jen-Shin Song
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Chun-Hwa Chen
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Wen-Hsing Lin
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Szu-Huei Wu
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - John T A Hsu
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Chuan Shih
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
| | - Hsing-Pang Hsieh
- Institute of Biotechnology and Pharmaceutical Research, National Health Research Institutes, 35 Keyan Road, Zhunan, Miaoli County 350, Taiwan, ROC
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Moreira RB, Peixoto RD, de Sousa Cruz MR. Clinical Response to Sorafenib in a Patient with Metastatic Colorectal Cancer and FLT3 Amplification. Case Rep Oncol 2015; 8:83-7. [PMID: 25848357 PMCID: PMC4361904 DOI: 10.1159/000375483] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Background A considerable number of patients with metastatic colorectal cancer progress after exhausting all approved standard therapies but maintain an adequate performance status and could be candidates for further treatment. We aim at reviewing our experience with sorafenib treatment of a patient with FLT3 mutation in refractory metastatic colorectal cancer. Methods Treatment with sorafenib of a patient with metastatic colorectal cancer and FLT3 translocation who had previously been heavily treated. Results The patient with metastatic colorectal cancer, aged 51 years, showed significant symptomatic and laboratory improvement with sorafenib treatment (400 mg twice daily). Conclusion The presented case illustrates how an aggressive and refractory colorectal tumor may respond well to targeted therapy.
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17
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Janke H, Pastore F, Schumacher D, Herold T, Hopfner KP, Schneider S, Berdel WE, Büchner T, Woermann BJ, Subklewe M, Bohlander SK, Hiddemann W, Spiekermann K, Polzer H. Activating FLT3 mutants show distinct gain-of-function phenotypes in vitro and a characteristic signaling pathway profile associated with prognosis in acute myeloid leukemia. PLoS One 2014; 9:e89560. [PMID: 24608088 PMCID: PMC3946485 DOI: 10.1371/journal.pone.0089560] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2013] [Accepted: 01/21/2014] [Indexed: 11/28/2022] Open
Abstract
About 30% of patients with acute myeloid leukemia (AML) harbour mutations of the receptor tyrosine kinase FLT3, mostly internal tandem duplications (ITD) and point mutations of the second tyrosine kinase domain (TKD). It was the aim of this study to comprehensively analyze clinical and functional properties of various FLT3 mutants. In 672 normal karyotype AML patients FLT3-ITD, but not FLT3-TKD mutations were associated with a worse relapse free and overall survival in multivariate analysis. In paired diagnosis-relapse samples FLT3-ITD showed higher stability (70%) compared to FLT3-TKD (30%). In vitro, FLT3-ITD induced a strong activating phenotype in Ba/F3 cells. In contrast, FLT3-TKD mutations and other point mutations – including two novel mutations – showed a weaker but clear gain-of-function phenotype with gradual increase in proliferation and protection from apoptosis. The pro-proliferative capacity of the investigated FLT3 mutants was associated with cell surface expression and tyrosine 591 phosphorylation of the FLT3 receptor. Western blot experiments revealed STAT5 activation only in FLT3-ITD positive cell lines, in contrast to FLT3-non-ITD mutants, which displayed an enhanced signal of AKT and MAPK activation. Gene expression analysis revealed distinct difference between FLT3-ITD and FLT3-TKD for STAT5 target gene expression as well as deregulation of SOCS2, ENPP2, PRUNE2 and ART3. FLT3-ITD and FLT3 point mutations show a gain-of-function phenotype with distinct signalling properties in vitro. Although poor prognosis in AML is only associated with FLT3-ITD, all activating FLT3 mutations can contribute to leukemogenesis and are thus potential targets for therapeutic interventions.
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Affiliation(s)
- Hanna Janke
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
- Clinical Cooperative Group Leukemia, Helmholtz Center Munich, Germany
- * E-mail:
| | - Friederike Pastore
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
- Clinical Cooperative Group Leukemia, Helmholtz Center Munich, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Daniela Schumacher
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
| | - Tobias Herold
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
- Clinical Cooperative Group Leukemia, Helmholtz Center Munich, Germany
| | - Karl-Peter Hopfner
- Department of Biochemistry, Gene Center, Ludwig-Maximilians-University Munich, Germany
| | - Stephanie Schneider
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
| | - Wolfgang E. Berdel
- Department of Medicine A, Hematology, Oncology and Pneumology, University Muenster, Germany
| | - Thomas Büchner
- Department of Medicine A, Hematology, Oncology and Pneumology, University Muenster, Germany
| | | | - Marion Subklewe
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
- Clinical Cooperative Group Immunotherapy, Helmholtz Center Munich, Germany
| | - Stefan K. Bohlander
- Department of Molecular Medicine and Pathology, University of Auckland, New Zealand
| | - Wolfgang Hiddemann
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
- Clinical Cooperative Group Leukemia, Helmholtz Center Munich, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Karsten Spiekermann
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
- Clinical Cooperative Group Leukemia, Helmholtz Center Munich, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Harald Polzer
- Department of Internal Medicine III, University Hospital Munich, Ludwig-Maximilians-University Munich, Germany
- Clinical Cooperative Group Leukemia, Helmholtz Center Munich, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
- German Cancer Research Center (DKFZ), Heidelberg, Germany
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Crenolanib is a potent inhibitor of FLT3 with activity against resistance-conferring point mutants. Blood 2013; 123:94-100. [PMID: 24227820 DOI: 10.1182/blood-2013-10-529313] [Citation(s) in RCA: 188] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Mutations of the type III receptor tyrosine kinase FLT3 occur in approximately 30% of acute myeloid leukemia patients and lead to constitutive activation. This has made FLT3-activating mutations an attractive drug target because they are probable driver mutations of this disease. As more potent FLT3 inhibitors are developed, a predictable development of resistance-conferring point mutations, commonly at residue D835, has been observed. Crenolanib is a highly selective and potent FLT3 tyrosine kinase inhibitor (TKI) with activity against the internal tandem duplication (FLT3/ITD) mutants and the FLT3/D835 point mutants. We tested crenolanib against a panel of D835 mutant cell lines and primary patient blasts and observed superior cytotoxic effects when compared with other available FLT3 TKIs such as quizartinib and sorafenib. Another potential advantage of crenolanib is its reduced inhibition of c-Kit compared with quizartinib. In progenitor cell assays, crenolanib was less disruptive of erythroid colony growth, which may result in relatively less myelosuppression than quizartinib. Finally, correlative data from an ongoing clinical trial demonstrate that acute myeloid leukemia patients can achieve sufficient levels of crenolanib to inhibit both FLT3/ITD and resistance-conferring FLT3/D835 mutants in vivo. Crenolanib is thus an important next-generation FLT3 TKI.
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Exome sequencing identifies putative drivers of progression of transient myeloproliferative disorder to AMKL in infants with Down syndrome. Blood 2013; 122:554-61. [PMID: 23733339 DOI: 10.1182/blood-2013-03-491936] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Some neonates with Down syndrome (DS) are diagnosed with self-regressing transient myeloproliferative disorder (TMD), and 20% to 30% of those progress to acute megakaryoblastic leukemia (AMKL). We performed exome sequencing in 7 TMD/AMKL cases and copy-number analysis in these and 10 additional cases. All TMD/AMKL samples contained GATA1 mutations. No exome-sequenced TMD/AMKL sample had other recurrently mutated genes. However, 2 of 5 TMD cases, and all AMKL cases, showed mutations/deletions other than GATA1, in genes proven as transformation drivers in non-DS leukemia (EZH2, APC, FLT3, JAK1, PARK2-PACRG, EXT1, DLEC1, and SMC3). One patient at the TMD stage revealed 2 clonal expansions with different GATA1 mutations, of which 1 clone had an additional driver mutation. Interestingly, it was the other clone that gave rise to AMKL after accumulating mutations in 7 other genes. Data suggest that GATA1 mutations alone are sufficient for clonal expansions, and additional driver mutations at the TMD stage do not necessarily predict AMKL progression. Later in infancy, leukemic progression requires "third-hit driver" mutations/somatic copy-number alterations found in non-DS leukemias. Putative driver mutations affecting WNT (wingless-related integration site), JAK-STAT (Janus kinase/signal transducer and activator of transcription), or MAPK/PI3K (mitogen-activated kinase/phosphatidylinositol-3 kinase) pathways were found in all cases, aberrant activation of which converges on overexpression of MYC.
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20
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Kampa-Schittenhelm KM, Heinrich MC, Akmut F, Rasp KH, Illing B, Döhner H, Döhner K, Schittenhelm MM. Cell cycle-dependent activity of the novel dual PI3K-MTORC1/2 inhibitor NVP-BGT226 in acute leukemia. Mol Cancer 2013; 12:46. [PMID: 23705826 PMCID: PMC3689638 DOI: 10.1186/1476-4598-12-46] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2012] [Accepted: 05/06/2013] [Indexed: 12/01/2022] Open
Abstract
Background Dysregulation of the PI3Kinase/AKT pathway is involved in the pathogenesis of many human malignancies. In acute leukemia, the AKT pathway is frequently activated, however mutations in the PI3K/AKT pathway are uncommon. In some cases, constitutive AKT activation can be linked to gain-of-function tyrosine kinase (TK) mutations upstream of the PI3K/AKT pathway. Inhibitors of the PI3K/AKT pathway are attractive candidates for cancer drug development, but so far clinical efficacy of PI3K inhibitors against various neoplasms has been moderate. Furthermore, specific MTORC1 inhibitors, acting downstream of AKT, have the disadvantage of activating AKT via feed-back mechanisms. We now evaluated the antitumor efficacy of NVP-BGT226, a novel dual pan-PI3K and MTORC1/2 inhibitor, in acute leukemia. Methods Native leukemia blasts were stained to analyze for AKT phosphorylation levels on a flow cytometer. Efficacy of NVP-BGT226 in comparison to a second dual inhibitor, NVP-BEZ235, was determined with regard to cellular proliferation, autophagy, cell cycle regulation and induction of apoptosis in in vitro and ex vivo cellular assays as well as on the protein level. An isogenic AKT-autoactivated Ba/F3 model, different human leukemia cell lines as well as native leukemia patient blasts were studied. Isobologram analyses were set up to calculate for (super) additive or antagonistic effects of two agents. Results We show, that phosphorylation of AKT is frequently augmented in acute leukemia. NVP-BGT226 as well as NVP-BEZ235 profoundly and globally suppress AKT signaling pathways, which translates into potent antiproliferative effects. Furthermore, NVP-BGT226 has potent proapoptotic effects in vitro as well as in ex vivo native blasts. Surprisingly and in contrast, NVP-BEZ235 leads to a profound G1/G0 arrest preventing significant induction of apoptosis. Combination with TK inhibitors, which are currently been tested in the treatment of acute leukemia subtypes, overcomes cell cycle arrest and results in (super)additive proapoptotic effects for NVP-BGT226 – but also for NVP-BEZ235. Importantly, mononuclear donor cells show lower phospho-AKT expression levels and consequently, relative insensitivity towards dual PI3K-MTORC1/2 inhibition. Conclusions Our data suggest a favorable antileukemic profile for NVP-BGT226 compared to NVP-BEZ235 – which provides a strong rationale for clinical evaluation of the dual PI3K-MTORC1/2 inhibitor NVP-BGT226 in acute leukemia.
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Affiliation(s)
- Kerstin Maria Kampa-Schittenhelm
- Department of Hematology, Oncology, Rheumatology, Immunology and Pulmology, University Hospital Tübingen, Otfried-Müller-Straße 10, 72076, Tübingen, Germany
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21
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Kampa-Schittenhelm KM, Heinrich MC, Akmut F, Döhner H, Döhner K, Schittenhelm MM. Quizartinib (AC220) is a potent second generation class III tyrosine kinase inhibitor that displays a distinct inhibition profile against mutant-FLT3, -PDGFRA and -KIT isoforms. Mol Cancer 2013; 12:19. [PMID: 23497317 PMCID: PMC3637582 DOI: 10.1186/1476-4598-12-19] [Citation(s) in RCA: 81] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2012] [Accepted: 02/19/2013] [Indexed: 12/04/2022] Open
Abstract
Background Activating mutations of class III receptor tyrosine kinases (RTK) FLT3, PDGFR and KIT are associated with multiple human neoplasms including hematologic malignancies, for example: systemic mast cell disorders (KIT), non-CML myeloproliferative neoplasms (PDGFR) and subsets of acute leukemias (FLT3 and KIT). First generation tyrosine kinase inhibitors (TKI) are rapidly being integrated into routine cancer care. However, the expanding spectrum of TK-mutations, bioavailability issues and the emerging problem of primary or secondary TKI-therapy resistance have lead to the search for novel second generation TKIs to improve target potency and to overcome resistant clones. Quizartinib was recently demonstrated to be a selective FLT3 inhibitor with excellent pharmacokinetics and promising in vivo activity in a phase II study for FLT3 ITD + AML patients. In vitro kinase assays have suggested that in addition to FLT3, quizartinib also targets related class III RTK isoforms. Methods Various FLT3 or KIT leukemia cell lines and native blasts were used to determine the antiproliferative and proapoptotic efficacy of quizartinib. To better compare differences between the mutant kinase isoforms, we generated an isogenic BaF3 cell line expressing different FLT3, KIT or BCR/ABL isoforms. Using immunoblotting, we examined the effects of quizartinib on activation of mutant KIT or FLT3 isoforms. Results Kinase inhibition of (mutant) KIT, PDGFR and FLT3 isoforms by quizartinib leads to potent inhibition of cellular proliferation and induction of apoptosis in in vitro leukemia models as well as in native leukemia blasts treated ex vivo. However, the sensitivity patterns vary widely depending on the underlying (mutant)-kinase isoform, with some isoforms being relatively insensitive to this agent (e.g. FLT3 D835V and KIT codon D816 mutations). Evaluation of sensitivities in an isogenic cellular background confirms a direct association with the underlying mutant-TK isoform – which is further validated by immunoblotting experiments demonstrating kinase inhibition consistent with the cellular sensitivity/resistance to quizartinib. Conclusion Quizartinib is a potent second-generation class III receptor TK-inhibitor – but specific, mutation restricted spectrum of activity may require mutation screening prior to therapy.
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Effector mechanisms of sunitinib-induced G1 cell cycle arrest, differentiation, and apoptosis in human acute myeloid leukaemia HL60 and KG-1 cells. Ann Hematol 2012. [PMID: 23180436 DOI: 10.1007/s00277-012-1627-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Acute myeloid leukaemia (AML) is a heterogeneous disease with dismal outcome. Sunitinib is an orally active inhibitor of multiple tyrosine kinase receptors approved for renal cell carcinoma and gastrointestinal stromal tumour that has also been studied for AML in several clinical trials. However, the precise mechanism of sunitinib action against AML remains unclear and requires further investigation. For this purpose, this study was conducted using human AML cell lines (HL60 and KG-1) and AML patients' mononucleated cells. Sunitinib induced G1 phase arrest associated with decreased cyclin D1, cyclin D3, and cyclin-dependent kinase (Cdk)2 and increased p27(Kip1), pRb1, and p130/Rb2 expression and phosphorylated activation of protein kinase C alpha and beta (PKCα/β). Selective PKCα/β inhibitor treatment abolished sunitinib-elicited AML differentiation, suggesting that PKCα/β may underlie sunitinib-induced monocytic differentiation. Furthermore, sunitinib increased pro-apoptotic molecule expression (Bax, Bak, PUMA, Fas, FasL, DR4, and DR5) and decreased anti-apoptotic molecule expression (Bcl-2 and Mcl-1), resulting in caspase-2, caspase-3, caspase-8, and caspase-9 activation and both death receptor and mitochondria-dependent apoptosis. Taken together, these findings provide evidence that sunitinib targets AML cells through both differentiation and apoptosis pathways. More clinical studies are urgently needed to demonstrate its optimal clinical applications in AML.
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Hernandez-Davies JE, Zape JP, Landaw EM, Tan X, Presnell A, Griffith D, Heinrich MC, Glaser KB, Sakamoto KM. The multitargeted receptor tyrosine kinase inhibitor linifanib (ABT-869) induces apoptosis through an Akt and glycogen synthase kinase 3β-dependent pathway. Mol Cancer Ther 2011; 10:949-59. [PMID: 21471285 DOI: 10.1158/1535-7163.mct-10-0904] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
The FMS-like receptor tyrosine kinase 3 (FLT3) plays an important role in controlling differentiation and proliferation of hematopoietic cells. Activating mutations in FLT3 occur in patients with acute myeloid leukemia (AML; 15%-35%), resulting in abnormal cell proliferation. Furthermore, both adult and pediatric patients with AML harboring the FLT3 internal tandem duplication (ITD) mutation have a poor prognosis. Several inhibitors have been developed to target mutant FLT3 for the treatment of AML, yet the molecular pathways affected by drug inhibition of the mutated FLT3 receptor alone have not been characterized as yet. Linifanib (ABT-869) is a multitargeted tyrosine kinase receptor inhibitor that suppresses FLT3 signaling. In this article, we show that treatment with linifanib inhibits proliferation and induces apoptosis in ITD mutant cells in vitro and in vivo. We show that treatment with linifanib reduces phosphorylation of Akt and glycogen synthase kinase 3β (GSK3β). In addition, we show that inhibition of GSK3β decreases linifanib-induced apoptosis. This study shows the importance of GSK3 as a potential target for AML therapy, particularly in patients with FLT3 ITD mutations.
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Affiliation(s)
- Jenny E Hernandez-Davies
- Division of Hematology-Oncology, Gwynne Hazen Cherry Memorial Laboratories, Mattel Children's Hospital UCLA, Jonsson Comprehensive Cancer Center, University of California-Los Angeles, Los Angeles, CA 90095, USA
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Jogireddy R, Dakas PY, Valot G, Barluenga S, Winssinger N. Synthesis of a resorcylic acid lactone (RAL) library using fluorous-mixture synthesis and profile of its selectivity against a panel of kinases. Chemistry 2010; 15:11498-506. [PMID: 19821461 DOI: 10.1002/chem.200901375] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A library of resorcylic acid lactones (RAL) containing a cis-enone moiety targeting kinases bearing a cysteine residue within the ATP-binding pocket was prepared using a fluorous-mixture synthesis and evaluated against a panel of 19 kinases thus providing important structure-activity trends. Two new analogues were then profiled for their selectivity against a panel of 402 kinases providing the broadest evaluation of this pharmacophores' selectivity.
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Affiliation(s)
- Rajamalleswaramma Jogireddy
- Institut de Science et Ingénierie Supramoléculaires (ISIS-UMR 7006), Université de Strasbourg-CNRS, 8 allée Gaspard Monge, 67000 Strasbourg, France
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Andolina JR, Corey SJ. Are kinases factors in core binding factor leukemia? Leuk Lymphoma 2009; 50:1397-8. [DOI: 10.1080/10428190903174375] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
In acute myeloid leukemia (AML), aberrant signal transduction enhances the survival and proliferation of hematopoietic progenitor cells. Activation of signal transduction in AML may occur through a variety of genetic alterations affecting different signaling molecules, such as the FLT3 and KIT receptor tyrosine kinases (RTKs) and members of the RAS family of guanine nucleotide-binding proteins. These mutant signaling proteins are attractive therapeutic targets; however, developing targeted therapies for each genotypic variant and determining the relationships between different genotypes and critical functional dependencies of the leukemic cells remain major challenges. As the large number of mutant signaling proteins that have been identified in AML are likely to reflect activation of a more limited number of downstream effector pathways, such as the RAF/MEK/ERK and PI3K/AKT cascades, targeting these unifying pathways may represent a more broadly applicable therapeutic strategy. Furthermore, integrative genomic studies combining DNA sequencing, DNA copy number analysis, transcriptional profiling, and functional genetic approaches hold great promise for identifying additional signaling abnormalities in AML that are relevant to leukemogenesis and can be exploited therapeutically. Eventually, it may become possible to use pathogenesis-oriented combinations of signal transduction inhibitors to improve the cure rate in AML patients.
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Affiliation(s)
- Claudia Scholl
- Division of Hematology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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Illmer T, Ehninger G. FLT3 kinase inhibitors in the management of acute myeloid leukemia. ACTA ACUST UNITED AC 2008; 8 Suppl 1:S24-34. [PMID: 18282363 DOI: 10.3816/clm.2007.s.030] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
FMS-like tyrosine kinase 3 (FLT3) is a receptor tyrosine kinase (TK) expressed by immature hematopoietic cells and is important for the normal development of stem cells and the immune system. Mutations of the juxtamembranous and TK domain of the gene are described in 30%-35% of patients with acute myeloid leukemia (AML). These mutations alter the biologic properties of AML and are associated with prognosis. In recent years, there has been an enormous development of potential inhibitors of FLT3 mutations. These substances are now being studied in clinical protocols. The initial trials reveal that, unlike in patients with chronic myeloid leukemia, TK inhibitor (TKI) therapy in AML is more complex. To date, most FLT3 TKIs investigated in clinical studies show a favorable toxicity profile with considerable biologic activity. However, refractory disease and/or the rapid development of resistance toward these new drugs remain major challenges. Strategies to circumvent this unsatisfactory clinical potential of FLT3 TKIs are mainly based on the combination with cytotoxic chemotherapy. Herein, we summarize results from studies using FLT3 TKIs as single agents and report on the first clinical trials investigating FLT3 TKIs in combination with chemotherapy.
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Affiliation(s)
- Thomas Illmer
- Medical Clinic and Policlinic I, Hospital of the Technical University, Technical University Dresden, Fetscherstrasse 74, Dresden, Germany
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Abstract
Acute myeloid leukemia with normal karyotype (NK-AML) represents a cytogenetic grouping with intermediate prognosis but substantial molecular and clinical heterogeneity. Within this subgroup, presence of FLT3 (FMS-like tyrosine kinase 3) internal tandem duplication (ITD) mutation predicts less favorable outcome. The goal of our study was to discover gene-expression patterns correlated with FLT3-ITD mutation and to evaluate the utility of a FLT3 signature for prognostication. DNA microarrays were used to profile gene expression in a training set of 65 NK-AML cases, and supervised analysis, using the Prediction Analysis of Microarrays method, was applied to build a gene expression-based predictor of FLT3-ITD mutation status. The optimal predictor, composed of 20 genes, was then evaluated by classifying expression profiles from an independent test set of 72 NK-AML cases. The predictor exhibited modest performance (73% sensitivity; 85% specificity) in classifying FLT3-ITD status. Remarkably, however, the signature outperformed FLT3-ITD mutation status in predicting clinical outcome. The signature may better define clinically relevant FLT3 signaling and/or alternative changes that phenocopy FLT3-ITD, whereas the signature genes provide a starting point to dissect these pathways. Our findings support the potential clinical utility of a gene expression-based measure of FLT3 pathway activation in AML.
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Abstract
Acute myeloid leukemia (AML) is a heterogeneous group of neoplastic disorders with great variability in clinical course and response to therapy, as well as in the genetic and molecular basis of the pathology. Major advances in the understanding of leukemogenesis have been made by the characterization and the study of acquired cytogenetic abnormalities, particularly reciprocal translocations observed in AML. Besides these major cytogenetic abnormalities, gene mutations also constitute key events in AML pathogenesis. In this review, we describe the contribution of known gene mutations to the understanding of AML pathogenesis and their clinical significance. To gain more insight in this understanding, we clustered these alterations in three groups: (1) mutations affecting genes that contribute to cell proliferation (FLT3, c-KIT, RAS, protein tyrosine standard phosphatase nonreceptor 11); (2) mutations affecting genes involved in myeloid differentiation (AML1 and CEBPA) and (3) mutations affecting genes implicated in cell cycle regulation or apoptosis (P53, NPM1). This nonexhaustive review aims to show how gene mutations interact with each other, how they contribute to refine prognosis and how they can be useful for risk-adapted therapeutic management of AML patients.
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Fröhling S, Scholl C, Levine RL, Loriaux M, Boggon TJ, Bernard OA, Berger R, Döhner H, Döhner K, Ebert BL, Teckie S, Golub TR, Jiang J, Schittenhelm MM, Lee BH, Griffin JD, Stone RM, Heinrich MC, Deininger MW, Druker BJ, Gilliland DG. Identification of driver and passenger mutations of FLT3 by high-throughput DNA sequence analysis and functional assessment of candidate alleles. Cancer Cell 2007; 12:501-13. [PMID: 18068628 DOI: 10.1016/j.ccr.2007.11.005] [Citation(s) in RCA: 152] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Revised: 09/01/2007] [Accepted: 11/01/2007] [Indexed: 11/19/2022]
Abstract
Mutations in the juxtamembrane and kinase domains of FLT3 are common in AML, but it is not known whether alterations outside these regions contribute to leukemogenesis. We used a high-throughput platform to interrogate the entire FLT3 coding sequence in AML patients without known FLT3 mutations and experimentally tested the consequences of each candidate leukemogenic allele. This approach identified gain-of-function mutations that activated downstream signaling and conferred sensitivity to FLT3 inhibition and alleles that were not associated with kinase activation, including mutations in the catalytic domain. These findings support the concept that acquired mutations in cancer may not contribute to malignant transformation and underscore the importance of functional studies to distinguish "driver" mutations underlying tumorigenesis from biologically neutral "passenger" alterations.
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Affiliation(s)
- Stefan Fröhling
- Division of Hematology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
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31
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FLT3 D835/I836 mutations are associated with poor disease-free survival and a distinct gene-expression signature among younger adults with de novo cytogenetically normal acute myeloid leukemia lacking FLT3 internal tandem duplications. Blood 2007; 111:1552-9. [PMID: 17940205 DOI: 10.1182/blood-2007-08-107946] [Citation(s) in RCA: 206] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The prognostic relevance of FLT3 D835/I836 mutations (FLT3-TKD) in cytogenetically normal acute myeloid leukemia (CN-AML) remains to be established. After excluding patients with FLT3 internal tandem duplications, we compared treatment outcome of 16 de novo CN-AML patients with FLT3-TKD with that of 123 patients with wild-type FLT3 (FLT3-WT), less than 60 years of age and similarly treated on Cancer and Leukemia Group B protocols. All FLT3-TKD(+) patients and 85% of FLT3-WT patients achieved a complete remission (P = .13). Disease-free survival (DFS) of FLT3-TKD(+) patients was worse than DFS of FLT3-WT patients (P = .01; estimated 3-year DFS rates, 31% vs 60%, respectively). In a multivariable analysis, FLT3-TKD was associated with worse DFS (P = .02) independent of NPM1 status and percentage of bone marrow blasts. To gain further biologic insights, a gene-expression signature differentiating FLT3-TKD(+) from FLT3-WT patients was identified. The signature (333 probe sets) included overexpression of VNN1, C3AR1, PTPN6, and multiple other genes involved in monocarboxylate transport activity, and underexpression of genes involved in signal transduction regulation. These associations with outcome, other prognostic markers, and the elucidated expression signature enhance our understanding of FLT3-TKD-associated biology and may lead to development of novel therapies that improve clinical outcome of CN-AML patients with FLT3-TKD.
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Chen H, Ma J, Li W, Eliseenkova AV, Xu C, Neubert TA, Miller WT, Mohammadi M. A molecular brake in the kinase hinge region regulates the activity of receptor tyrosine kinases. Mol Cell 2007; 27:717-30. [PMID: 17803937 PMCID: PMC2094128 DOI: 10.1016/j.molcel.2007.06.028] [Citation(s) in RCA: 197] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2007] [Revised: 05/24/2007] [Accepted: 06/21/2007] [Indexed: 01/07/2023]
Abstract
Activating mutations in the tyrosine kinase domain of receptor tyrosine kinases (RTKs) cause cancer and skeletal disorders. Comparison of the crystal structures of unphosphorylated and phosphorylated wild-type FGFR2 kinase domains with those of seven unphosphorylated pathogenic mutants reveals an autoinhibitory "molecular brake" mediated by a triad of residues in the kinase hinge region of all FGFRs. Structural analysis shows that many other RTKs, including PDGFRs, VEGFRs, KIT, CSF1R, FLT3, TEK, and TIE, are also subject to regulation by this brake. Pathogenic mutations activate FGFRs and other RTKs by disengaging the brake either directly or indirectly.
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Affiliation(s)
- Huaibin Chen
- Department of Pharmacology, New York University School of Medicine, New York, NY 10016, USA
| | - Jinghong Ma
- Department of Pharmacology, New York University School of Medicine, New York, NY 10016, USA
| | - Wanqing Li
- Department of Physiology and Biophysics, School of Medicine, State University of New York at Stony Brook, Stony Brook, New York 11794, USA
| | - Anna V. Eliseenkova
- Department of Pharmacology, New York University School of Medicine, New York, NY 10016, USA
| | - Chongfeng Xu
- Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY 10016, USA
| | - Thomas A. Neubert
- Department of Pharmacology, New York University School of Medicine, New York, NY 10016, USA
- Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, NY 10016, USA
| | - W. Todd Miller
- Department of Physiology and Biophysics, School of Medicine, State University of New York at Stony Brook, Stony Brook, New York 11794, USA
| | - Moosa Mohammadi
- Department of Pharmacology, New York University School of Medicine, New York, NY 10016, USA
- To whom correspondence should be addressed: Moosa Mohammadi, Ph.D, Tel: (212) 263-2907, Fax: (212) 263-7133, E-mail:
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Colovic N, Tosic N, Aveic S, Djuric M, Milic N, Bumbasirevic V, Colovic M, Pavlovic S. Importance of early detection and follow-up of FLT3 mutations in patients with acute myeloid leukemia. Ann Hematol 2007; 86:741-7. [PMID: 17579862 DOI: 10.1007/s00277-007-0325-3] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2007] [Accepted: 05/28/2007] [Indexed: 11/24/2022]
Abstract
Mutations in the fms-like tyrosine kinase 3 (FLT3) gene, such as internal tandem duplication (FLT3/ITD) in the juxtamembrane domain and point mutations in the tyrosine kinase domain, are the most common abnormalities in acute myeloid leukemia (AML). FLT3/ITD and FLT3/D835 mutations were analyzed in 113 Serbian adult AML patients using polymerase chain reaction. Twenty patients were found to be FLT3/ITD positive (17.7%). The mutations occurred most frequently in M5 and M0 subtypes of AML. They were mainly associated with the normal karyotype. All patients harboring FLT3/ITD had a higher number of white blood cells than patients without it (p = 0.027). FLT3/ITD mutations were associated with lower complete remission (CR) rate (chi (2 )= 5.706; p = 0.017) and shorter overall survival (OS; Log rank = 8.76; p = 0.0031). As for disease-free survival, the difference between FLT3/ITD-positive and FLT3/ITD-negative patients was not statistically significant (Log rank = 0.78; p = 0.3764). In multivariate analysis, the presence of FLT3/ITD mutations was the most significant prognostic factor for both OS and CR rate (p = 0.0287; relative risk = 1.73; 95% CI = 1.06-2.82). However, in the group of patients with the intermediate-risk karyotype, the mere presence of FLT3/ITD was not associated with inferior clinical outcome. FLT3/D835 point mutation was found in four patients (3.5%) only. Follow-up of the FLT3/ITD-positive patients revealed stability of this mutation during the course of the disease. However, changes in the pattern of FLT3/D835 mutations in initial and relapsed AML were observed. Our results indicate an association of FLT3/ITD with the adverse outcome in AML patients treated with standard induction chemotherapy. Because FLT3/ITD mutation is a target for specific therapeutic inhibition, its early detection could be helpful in clinical practice.
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MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Antineoplastic Combined Chemotherapy Protocols/administration & dosage
- Chromosome Aberrations
- Disease-Free Survival
- Female
- Follow-Up Studies
- Humans
- Leukemia, Myeloid, Acute/blood
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myeloid, Acute/mortality
- Leukemia, Myeloid, Acute/therapy
- Leukocyte Count
- Male
- Middle Aged
- Point Mutation
- Recurrence
- Risk Factors
- Stem Cell Transplantation
- Survival Rate
- Transplantation, Homologous
- Yugoslavia
- fms-Like Tyrosine Kinase 3/genetics
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Affiliation(s)
- Natasa Colovic
- Institute of Hematology, Clinical Center of Serbia, Belgrade, Serbia
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Peterson LF, Boyapati A, Ahn EY, Biggs JR, Okumura AJ, Lo MC, Yan M, Zhang DE. Acute myeloid leukemia with the 8q22;21q22 translocation: secondary mutational events and alternative t(8;21) transcripts. Blood 2007; 110:799-805. [PMID: 17412887 PMCID: PMC1924771 DOI: 10.1182/blood-2006-11-019265] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Nonrandom and somatically acquired chromosomal translocations can be identified in nearly 50% of human acute myeloid leukemias. One common chromosomal translocation in this disease is the 8q22;21q22 translocation. It involves the AML1 (RUNX1) gene on chromosome 21 and the ETO (MTG8, RUNX1T1) gene on chromosome 8 generating the AML1-ETO fusion proteins. In this review, we survey recent advances made involving secondary mutational events and alternative t(8;21) transcripts in relation to understanding AML1-ETO leukemogenesis.
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MESH Headings
- Animals
- Cell Transformation, Neoplastic/genetics
- Cell Transformation, Neoplastic/metabolism
- Chromosomes, Human, Pair 21/genetics
- Chromosomes, Human, Pair 21/metabolism
- Chromosomes, Human, Pair 8/genetics
- Chromosomes, Human, Pair 8/metabolism
- Core Binding Factor Alpha 2 Subunit/biosynthesis
- Core Binding Factor Alpha 2 Subunit/genetics
- Humans
- Leukemia, Myeloid, Acute/genetics
- Leukemia, Myeloid, Acute/metabolism
- Leukemia, Myeloid, Acute/pathology
- Mice
- Oncogene Proteins, Fusion/biosynthesis
- Oncogene Proteins, Fusion/genetics
- RUNX1 Translocation Partner 1 Protein
- Transcription, Genetic
- Translocation, Genetic
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Affiliation(s)
- Luke F Peterson
- Department of Molecular and Experimental Medicine, Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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35
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Dong X, Han ZC, Yang R. Angiogenesis and antiangiogenic therapy in hematologic malignancies. Crit Rev Oncol Hematol 2006; 62:105-18. [PMID: 17188504 DOI: 10.1016/j.critrevonc.2006.11.006] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2006] [Revised: 11/13/2006] [Accepted: 11/15/2006] [Indexed: 12/15/2022] Open
Abstract
Angiogenesis, the generation of new blood capillaries from preexisting blood vessels, is tightly regulated in the adult organism. Although many of the initial studies were performed on solid tumors, increasing evidence indicates that angiogenesis also plays an important role in hematologic malignancies. Overexpression of angiogenic factors in particular VEGF and bFGF in most hematologic malignancies may explain the increased angiogenesis found in these malignancies and correlate with poor prognosis as well as decreased overall survival. In this review, we focus on the current literature of angiogenesis and antiangiogenic therapy in hematologic malignancies, and finally describe advances and potential challenges in antiangiogenic treatment in hematologic malignancies.
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Affiliation(s)
- Xunwei Dong
- State Key Laboratory of Experimental Hematology, Institute of Hematology and Hospital of Blood Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, 288 Nanjing Road, Tianjin 300020, PR China
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