1
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Zhou Q, Tu X, Hou X, Yu J, Zhao F, Huang J, Kloeber J, Olson A, Gao M, Luo K, Zhu S, Wu Z, Zhang Y, Sun C, Zeng X, Schoolmeester KJ, Weroha JS, Hu X, Jiang Y, Wang L, Mutter RW, Lou Z. Syk-dependent homologous recombination activation promotes cancer resistance to DNA targeted therapy. Drug Resist Updat 2024; 74:101085. [PMID: 38636338 DOI: 10.1016/j.drup.2024.101085] [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: 09/27/2023] [Revised: 04/03/2024] [Accepted: 04/08/2024] [Indexed: 04/20/2024]
Abstract
Enhanced DNA repair is an important mechanism of inherent and acquired resistance to DNA targeted therapies, including poly ADP ribose polymerase (PARP) inhibition. Spleen associated tyrosine kinase (Syk) is a non-receptor tyrosine kinase acknowledged for its regulatory roles in immune cell function, cell adhesion, and vascular development. This study presents evidence indicating that Syk expression in high-grade serous ovarian cancer and triple-negative breast cancers promotes DNA double-strand break resection, homologous recombination (HR), and subsequent therapeutic resistance. Our investigations reveal that Syk is activated by ATM following DNA damage and is recruited to DNA double-strand breaks by NBS1. Once localized to the break site, Syk phosphorylates CtIP, a pivotal mediator of resection and HR, at Thr-847 to promote repair activity, particularly in Syk-expressing cancer cells. Inhibition of Syk or its genetic deletion impedes CtIP Thr-847 phosphorylation and overcomes the resistant phenotype. Collectively, our findings suggest a model wherein Syk fosters therapeutic resistance by promoting DNA resection and HR through a hitherto uncharacterized ATM-Syk-CtIP pathway. Moreover, Syk emerges as a promising tumor-specific target to sensitize Syk-expressing tumors to PARP inhibitors, radiation and other DNA-targeted therapies.
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Affiliation(s)
- Qin Zhou
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Xinyi Tu
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Xiaonan Hou
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Jia Yu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, United States
| | - Fei Zhao
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Jinzhou Huang
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Jake Kloeber
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Anna Olson
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Ming Gao
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Kuntian Luo
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Shouhai Zhu
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Zheming Wu
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Yong Zhang
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Chenyu Sun
- AMITA Health Saint Joseph Hospital Chicago, Chicago, IL 60657, United States
| | - Xiangyu Zeng
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | | | - John S Weroha
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Xiwen Hu
- Nursing Department, Rochester Community and Technical College, Rochester, MN 55904, United States
| | - Yanxia Jiang
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, United States
| | - Liewei Wang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, United States
| | - Robert W Mutter
- Department of Radiation Oncology, Mayo Clinic, Rochester, MN 55905, United States; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, United States.
| | - Zhenkun Lou
- Department of Oncology, Mayo Clinic, Rochester, MN 55905, United States; Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55905, United States.
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2
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Samanta S, Sk MF, Koirala S, Kar P. Exploring molecular interactions of potential inhibitors against the spleen tyrosine kinase implicated in autoimmune disorders via virtual screening and molecular dynamics simulations. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2023:1-29. [PMID: 37881946 DOI: 10.1080/1062936x.2023.2266364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 09/19/2023] [Indexed: 10/27/2023]
Abstract
The spleen tyrosine kinase (Syk) plays a pivotal role in immune cells' signal transduction mechanism. While fostamatinib, an FDA-approved Syk inhibitor, is currently used to treat immune thrombocytopenia, the search for improved Syk-targeted medications to treat autoimmune diseases is still underway. Herein, we screened 38,493 compounds against Syk and selected eight leads based on the docking score and ADMET properties, and performed 3× 200 ns long molecular dynamics simulations of the apo and Syk-ligand complexes. We considered R406, the active component of fostamatinib, as a control. The molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) calculations demonstrated the lead1 (Δ G b i n d = -30.35 kcal/mol) exhibited a similar binding free energy as the control (Δ G b i n d = -29.82 kcal/mol). The Syk stabilizing effect of lead1 was also indicated in its network features, sampling space, and residual correlation motion analysis. We further generated 100 structural analogues of lead1 using deep learning, and one of the analogues displayed a better binding free energy (Δ G b i n d = -47.58 kcal/mol) compared to the control or lead1, facilitated by more favourable van der Waals interactions and lesser binding-opposing net polar forces. This analogue may be further exploited to develop effective therapeutics against Syk-associated diseases after validation in vitro and in vivo.
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Affiliation(s)
- S Samanta
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Madhya Pradesh, India
| | - M F Sk
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Madhya Pradesh, India
- Theoretical and Computational Biophysics Group, NIH Resource for Macromolecular Modeling and Visualization, Beckman Institute for Advanced Science and Technology, University of Illinois Urbana-Champaign, Urbana, IL, USA
| | - S Koirala
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Madhya Pradesh, India
| | - P Kar
- Department of Biosciences and Biomedical Engineering, Indian Institute of Technology Indore, Madhya Pradesh, India
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3
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Crowley HM, Georgantzoglou N, Tse JY, Williams EA, Mata DA, Martin SS, Guitart J, Bridge JA, Linos K. Expanding Our Knowledge of Molecular Pathogenesis in Histiocytoses: Solitary Soft Tissue Histiocytomas in Children With a Novel CLTC::SYK Fusion. Am J Surg Pathol 2023; 47:1108-1115. [PMID: 37522373 DOI: 10.1097/pas.0000000000002102] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/01/2023]
Abstract
The histiocytoses comprise a histopathologically and clinically diverse group of disorders bearing recurrent genomic alterations, commonly involving the BRAF gene and mitogen-activated protein kinase pathway. In the current study, a novel CLTC :: SYK fusion in 3 cases of a histopathologically distinct histiocytic neoplasm arising as solitary soft tissue lesions in children identified by next-generation sequencing and fluorescence in situ hybridization is described. Morphologically, all 3 neoplasms were composed of sheets of cells with round-oval nuclei and vacuolated eosinophilic cytoplasm but, in contrast to classic juvenile xanthogranuloma (JXG), Touton giant cells were absent. A separate cohort of classic JXG cases subsequently profiled by fluorescence in situ hybridization were negative for the presence of a CLTC::SYK fusion suggesting that CLTC::SYK fusion-positive histiocytoma is genetically and histologically distinct from JXG. We postulate that the CLTC::SYK fusion leads to aberrant activation of the SYK kinase, which is involved in variable pathways, including mitogen-activated protein kinase. The identification of a novel CLTC::SYK fusion may pave the way for the development of targeted therapeutic options for aggressive disease.
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Affiliation(s)
- Helena M Crowley
- Division of Pediatric Surgery and Urology, University of Maryland Children's Hospital
| | - Natalia Georgantzoglou
- Department of Pathology and Laboratory Medicine, Dartmouth Hitchcock Medical Center, Lebanon, NH
| | | | | | | | - Stuart S Martin
- Department of Pharmacology and Physiology, University of Maryland School of Medicine, Baltimore, MD
| | - Joan Guitart
- Department of Dermatology, Northwestern University Feinberg School of Medicine, Chicago, IL
| | - Julia A Bridge
- Division of Molecular Pathology, ProPath, Dallas, TX
- Department of Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE
| | - Konstantinos Linos
- Department of Pathology & Laboratory Medicine, Memorial Sloan Kettering Cancer Center, New York, NY
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4
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Hughes K, Evans K, Earley EJ, Smith CM, Erickson SW, Stearns T, Philip VM, Neuhauser SB, Chuang JH, Jocoy EL, Bult CJ, Teicher BA, Smith MA, Lock RB. In vivo activity of the dual SYK/FLT3 inhibitor TAK-659 against pediatric acute lymphoblastic leukemia xenografts. Pediatr Blood Cancer 2023; 70:e30503. [PMID: 37339930 PMCID: PMC10730772 DOI: 10.1002/pbc.30503] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Revised: 04/27/2023] [Accepted: 06/04/2023] [Indexed: 06/22/2023]
Abstract
BACKGROUND While children with acute lymphoblastic leukemia (ALL) experience close to a 90% likelihood of cure, the outcome for certain high-risk pediatric ALL subtypes remains dismal. Spleen tyrosine kinase (SYK) is a prominent cytosolic nonreceptor tyrosine kinase in pediatric B-lineage ALL (B-ALL). Activating mutations or overexpression of Fms-related receptor tyrosine kinase 3 (FLT3) are associated with poor outcome in hematological malignancies. TAK-659 (mivavotinib) is a dual SYK/FLT3 reversible inhibitor, which has been clinically evaluated in several other hematological malignancies. Here, we investigate the in vivo efficacy of TAK-659 against pediatric ALL patient-derived xenografts (PDXs). METHODS SYK and FLT3 mRNA expression was quantified by RNA-seq. PDX engraftment and drug responses in NSG mice were evaluated by enumerating the proportion of human CD45+ cells (%huCD45+ ) in the peripheral blood. TAK-659 was administered per oral at 60 mg/kg daily for 21 days. Events were defined as %huCD45+ ≥ 25%. In addition, mice were humanely killed to assess leukemia infiltration in the spleen and bone marrow (BM). Drug efficacy was assessed by event-free survival and stringent objective response measures. RESULTS FLT3 and SYK mRNA expression was significantly higher in B-lineage compared with T-lineage PDXs. TAK-659 was well tolerated and significantly prolonged the time to event in six out of eight PDXs tested. However, only one PDX achieved an objective response. The minimum mean %huCD45+ was significantly reduced in five out of eight PDXs in TAK-659-treated mice compared with vehicle controls. CONCLUSIONS TAK-659 exhibited low to moderate single-agent in vivo activity against pediatric ALL PDXs representative of diverse subtypes.
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Affiliation(s)
- Keira Hughes
- Children's Cancer Institute, Lowy Cancer Research Centre, School of Clinical Medicine, UNSW Medicine & Health, Centre for Childhood Cancer Research, UNSW Sydney, Sydney, NSW, Australia
| | - Kathryn Evans
- Children's Cancer Institute, Lowy Cancer Research Centre, School of Clinical Medicine, UNSW Medicine & Health, Centre for Childhood Cancer Research, UNSW Sydney, Sydney, NSW, Australia
| | - Eric J Earley
- RTI International, Research Triangle Park, North Carolina, USA
| | - Christopher M Smith
- Children's Cancer Institute, Lowy Cancer Research Centre, School of Clinical Medicine, UNSW Medicine & Health, Centre for Childhood Cancer Research, UNSW Sydney, Sydney, NSW, Australia
| | | | - Tim Stearns
- The Jackson Laboratory, Bar Harbor, Maine, USA
| | | | | | | | | | | | | | | | - Richard B Lock
- Children's Cancer Institute, Lowy Cancer Research Centre, School of Clinical Medicine, UNSW Medicine & Health, Centre for Childhood Cancer Research, UNSW Sydney, Sydney, NSW, Australia
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5
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Zhou Q, Tu X, Hou X, Yu J, Zhao F, Huang J, Kloeber J, Olson A, Gao M, Luo K, Zhu S, Wu Z, Zhang Y, Sun C, Zeng X, Schoolmeester K, Weroha J, Wang L, Mutter R, Lou Z. Syk-dependent alternative homologous recombination activation promotes cancer resistance to DNA targeted therapy. RESEARCH SQUARE 2023:rs.3.rs-2922520. [PMID: 37333340 PMCID: PMC10275042 DOI: 10.21203/rs.3.rs-2922520/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/20/2023]
Abstract
Enhanced DNA repair is an important mechanism of inherent and acquired resistance to DNA targeted therapies, including poly ADP ribose polymerase inhibition. Spleen associated tyrosine kinase (Syk) is a non-receptor tyrosine kinase known to regulate immune cell function, cell adhesion, and vascular development. Here, we report that Syk can be expressed in high grade serous ovarian cancer and triple negative breast cancers and promotes DNA double strand break resection, homologous recombination (HR) and therapeutic resistance. We found that Syk is activated by ATM following DNA damage and is recruited to DNA double strand breaks by NBS1. Once at the break site, Syk phosphorylates CtIP, a key mediator of resection and HR, at Thr-847 to promote repair activity, specifically in Syk expressing cancer cells. Syk inhibition or genetic deletion abolished CtIP Thr-847 phosphorylation and overcame the resistant phenotype. Collectively, our findings suggest that Syk drives therapeutic resistance by promoting DNA resection and HR through a novel ATM-Syk-CtIP pathway, and that Syk is a new tumor-specific target to sensitize Syk-expressing tumors to PARPi and other DNA targeted therapy.
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Affiliation(s)
- Qin Zhou
- Department of Radiation Oncology, Mayo Clinic
| | - Xinyi Tu
- Department of Radiation Oncology, Mayo Clinic
| | | | - Jia Yu
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic
| | - Fei Zhao
- Department of Oncology, Mayo Clinic
| | | | | | | | - Ming Gao
- Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences
| | | | | | | | | | | | | | | | | | - Liewei Wang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic
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6
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Precursor B-ALL Cell Lines Differentially Respond to SYK Inhibition by Entospletinib. Int J Mol Sci 2021; 22:ijms22020592. [PMID: 33435587 PMCID: PMC7827334 DOI: 10.3390/ijms22020592] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Revised: 01/04/2021] [Accepted: 01/07/2021] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Impaired B-cell receptor (BCR) function has been associated with the progress of several B-cell malignancies. The spleen tyrosine kinase (SYK) represents a potential therapeutic target in a subset of B-cell neoplasias. In precursor B-acute lymphoblastic leukemia (B-ALL), the pathogenic role and therapeutic potential of SYK is still controversially discussed. We evaluate the application of the SYK inhibitor entospletinib (Ento) in pre- and pro-B-ALL cell lines, characterizing the biologic and molecular effects. METHODS SYK expression was characterized in pre-B-ALL (NALM-6) and pro-B-ALL cell lines (SEM and RS4;11). The cell lines were exposed to different Ento concentrations and the cell biological response analyzed by proliferation, metabolic activity, apoptosis induction, cell-cycle distribution and morphology. BCR pathway gene expression and protein modulations were further characterized. RESULTS Ento significantly induced anti-proliferative and pro-apoptotic effects in NALM-6 and SEM, while barely affecting RS4;11. Targeted RNAseq revealed pronounced gene expression modulation only in NALM-6, while Western Blot analyses demonstrated that vital downstream effector proteins, such as pAKT, pERK, pGSK3β, p53 and BCL-6, were affected by Ento exposure in the inhibitor-sensitive cell lines. CONCLUSION Different acting modes of Ento, independent of pre-BCR dependency, were characterized, unexpected in SEM. Accordingly, SYK classifies as a potential target structure in a subset of pro-B-ALLs.
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7
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Alwithenani AI, Althubiti MA. Systematic Analysis of Spleen Tyrosine Kinase Expression and its Clinical Outcomes in Various Cancers. SAUDI JOURNAL OF MEDICINE & MEDICAL SCIENCES 2020; 8:95-104. [PMID: 32587490 PMCID: PMC7305679 DOI: 10.4103/sjmms.sjmms_300_19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2019] [Revised: 10/28/2019] [Accepted: 02/06/2020] [Indexed: 12/04/2022]
Abstract
Background: Spleen tyrosine kinase (SYK) is an important enzyme in the proliferation and differentiation of all hematopoietic tissues. Its role as a cancer driver is well documented in liquid tumors; however, cumulative evidence has suggested an opposite role in other tumor types. Objectives: To systematically assess the expression of SYK, its prognostic value and epigenetic status in different cancers using bioinformatics tools. Methods: In this bioinformatics study, Oncomine database and cBioPortal were used to study the SYK gene expression, Kaplan–Meier plotter to study its prognostic value and MethHC to assess the SYK gene methylation in various cancers. Results: From 542 unique analyses of the SYK gene, it was found to be overexpressed in bladder, breast and colon cancers but downregulated in leukemia, lymphoma and myeloma. Compared with normal tissues, breast and brain tumors showed an overexpression of the SYK gene, whereas lymphoma and leukemia had lower expression. The Kaplan–Meier survival analysis revealed that SYK expression in pancreatic, gastric, liver and lung patients were correlated with better overall survival. Using cBioPortal, prostate cancer was found to have the highest SYK gene mutation frequency, and the mean expression was highest in diffuse large B-cell lymphoma, acute myeloid leukemia and thymoma. Using the MethHC database, SYK promoter hypermethylation was found to be significantly higher in breast, renal, liver, lung, pancreatic, prostatic, skin and stomach cancers compared with the normal tissue (P < 0.005). Conclusion: The results of this study indicate the potential use of SYK as a diagnostic and therapeutic target for different type of cancers. However, further experimental data are required to validate these results before use of SYK in clinical settings.
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Affiliation(s)
- Akram I Alwithenani
- Department of Laboratory Medicine, Faculty of Applied Medical Sciences, Umm Al-Qura University, Makkah, Saudi Arabia
| | - Mohammad A Althubiti
- Department of Biochemistry, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia
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8
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SYK Inhibition Potentiates the Effect of Chemotherapeutic Drugs on Neuroblastoma Cells in Vitro. Cancers (Basel) 2019; 11:cancers11020202. [PMID: 30744170 PMCID: PMC6406899 DOI: 10.3390/cancers11020202] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2018] [Revised: 02/04/2019] [Accepted: 02/06/2019] [Indexed: 12/13/2022] Open
Abstract
Neuroblastoma is a malignancy arising from the developing sympathetic nervous system and the most common and deadly cancer of infancy. New therapies are needed to improve the prognosis for high-risk patients and to reduce toxicity and late effects. Spleen tyrosine kinase (SYK) has previously been identified as a promising drug target in various inflammatory diseases and cancers but has so far not been extensively studied as a potential therapeutic target in neuroblastoma. In this study, we observed elevated SYK gene expression in neuroblastoma compared to neural crest and benign neurofibroma. While SYK protein was detected in the majority of examined neuroblastoma tissues it was less frequently observed in neuroblastoma cell lines. Depletion of SYK by siRNA and the use of small molecule SYK inhibitors significantly reduced the cell viability of neuroblastoma cell lines expressing SYK protein. Moreover, SYK inhibition decreased ERK1/2 and Akt phosphorylation. The SYK inhibitor BAY 61-3606 enhanced the effect of different chemotherapeutic drugs. Transient expression of a constitutive active SYK variant increased the viability of neuroblastoma cells independent of endogenous SYK levels. Collectively, our findings suggest that targeting SYK in combination with conventional chemotherapy should be further evaluated as a treatment option in neuroblastoma.
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9
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Althubiti M. Spleen Tyrosine Kinase Inhibition Modulates p53 Activity. J Cell Death 2017; 10:1179066017731564. [PMID: 29249894 PMCID: PMC5726622 DOI: 10.1177/1179066017731564] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 08/13/2017] [Indexed: 01/09/2023] Open
Abstract
Spleen tyrosine kinase (SYK) is a cytoplasmic enzyme that promotes survival and proliferation of B cells. SYK inhibition has shown promising results in the treatment of arthritis and chronic lymphocytic leukemia (CLL). However, in other context, it has been shown that SYK overexpression in epithelial cancer cells induced senescence in p53-dependent mechanism, which underscored its antineoplastic activity in vitro. Here, we show that SYK was induced in response of DNA damage in parallel with p53 levels. In addition, using chemical inhibitors of SYK reduced p53 levels in HCT116 and HT1080 cell lines, which underlines the role of SYK inhibition on p53 activity. Furthermore, SYK inhibition modulated the cell growth, which resulted in a decreasing in cell death. Interestingly, SYK expression showed a positive prognosis in patients with solid tumors in correlations with their survival rates, as expected negative correlation was seen between SYK expression and survival rate of patients with CLL. In conclusion, these findings demonstrate that SYK inhibition modulates p53 expression and activity in HCT116 and HT1080 cells. Reconsidering using of SYK inhibitors in clinical setting in the future should be evaluated carefully in accordance with these findings to prevent the formation of secondary malignancies.
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Affiliation(s)
- Mohammad Althubiti
- Biochemistry Department, Faculty of Medicine, Umm Al-Qura University, Makkah, Saudi Arabia
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10
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Zheng T, Wang A, Hu D, Wang Y. Molecular mechanisms of breast cancer metastasis by gene expression profile analysis. Mol Med Rep 2017; 16:4671-4677. [PMID: 28791367 PMCID: PMC5647040 DOI: 10.3892/mmr.2017.7157] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 05/18/2017] [Indexed: 01/08/2023] Open
Abstract
Metastasis is the main cause of breast cancer‑related mortalities. The present study aimed to uncover the relevant molecular mechanisms of breast cancer metastasis and to explore potential biomarkers that may be used for prognosis. Expression profile microarray data GSE8977, which contained 22 stroma samples (15 were from normal breast and 7 were from invasive ductal carcinoma tumor samples), were obtained from the Gene Expression Omnibus database. Following data preprocessing, differentially expressed genes (DEGs) were selected based on analyses conducted using the linear models for microarray analysis package from R and Bioconductor software. The resulting data were used in subsequent function and pathway enrichment analyses, as well as protein‑protein interaction (PPI) network and subnetwork analyses. Transcription factors (TFs) and tumor‑associated genes were also identified among the DEGs. A total of 234 DEGs were identified, which were enriched in immune response, cell differentiation and cell adhesion‑related functions and pathways. Downregulated DEGs included TFs, such as the proto‑oncogene SPI1, pre‑B‑cell leukemia homeobox 3 (PBX3) and lymphoid enhancer‑binding factor 1 (LEF1), as well as tumor suppressors (TSs), such as capping actin protein, gelsolin like (CAPG) and tumor protein p53‑inducible nuclear protein 1 (TP53INP1). Upregulated DEGs also included TFs and tumor suppressors, consisting of transcription factor 7‑like 2 (TCF7L2) and pleiomorphic adenoma gene‑like 1 (PLAGL1). DEGs that were identified at the hub nodes in the PPI network and the subnetwork were epidermal growth factor receptor (EGFR) and spleen‑associated tyrosine kinase (SYK), respectively. Several genes crucial in the metastasis of breast cancer were identified, which may serve as potential biomarkers, many of which were associated with cell adhesion, proliferation or immune response, and may influence breast cancer metastasis by regulating these function or pathways.
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Affiliation(s)
- Tianying Zheng
- Department of Chemotherapy, Cancer Center, Qilu Hospital of Shandong University, Jinan, Shandong 250012, P.R. China
| | - Aijun Wang
- Department of Chemotherapy, Cancer Center, Qilu Hospital of Shandong University, Jinan, Shandong 250012, P.R. China
| | - Dongyan Hu
- Department of Chemotherapy, Cancer Center, Qilu Hospital of Shandong University, Jinan, Shandong 250012, P.R. China
| | - Yonggang Wang
- Department of Chemotherapy, Cancer Center, Qilu Hospital of Shandong University, Jinan, Shandong 250012, P.R. China
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11
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Afifiyan N, Tillman B, French BA, Masouminia M, Samadzadeh S, French SW. Over expression of proteins that alter the intracellular signaling pathways in the cytoplasm of the liver cells forming Mallory-Denk bodies. Exp Mol Pathol 2017; 102:106-114. [PMID: 28089901 DOI: 10.1016/j.yexmp.2017.01.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 01/12/2017] [Indexed: 12/12/2022]
Abstract
In this study, liver biopsy sections fixed in formalin and embedded in paraffin (FFPE) from patients with alcoholic hepatitis (AH) were used. The results showed that the expression of the SYK protein was up regulated by RNA-seq and real time PCR analyses in the alcoholic hepatitis patients compared to controls. The results were supported by using the IHC fluorescent antibody staining intensity morphometric quantitation. Morphometric quantification of fluorescent intensity measurement showed a two fold increase in SYK protein in the cytoplasm of the cells forming MDBs compared to surrounding normal hepatocytes. The expression of AKT1 was also analyzed. AKT1 is a serine/threonine-specific protein kinase that plays a key role in multiple cellular processes such as glucose metabolism, apoptosis, cell proliferation, transcription and cell migration. The AKT protein was also increased in hepatocyte balloon cells forming MDBs. This observation demonstrates the role of SYK and its subsequent effect on the internal signaling pathways such as PI3K/AKT as well as p70S6K, as a potential multifunctional target in protein quality control mechanisms of hepatocytes when ER stress is activated.
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Affiliation(s)
- N Afifiyan
- Department of Pathology, Harbor UCLA Medical Center and Los Angeles BioMedical Institute, 1000W, Carson, Torrance, CA 90509, United States
| | - B Tillman
- Department of Pathology, Harbor UCLA Medical Center and Los Angeles BioMedical Institute, 1000W, Carson, Torrance, CA 90509, United States
| | - B A French
- Department of Pathology, Harbor UCLA Medical Center and Los Angeles BioMedical Institute, 1000W, Carson, Torrance, CA 90509, United States
| | - M Masouminia
- Department of Pathology, Harbor UCLA Medical Center and Los Angeles BioMedical Institute, 1000W, Carson, Torrance, CA 90509, United States
| | - S Samadzadeh
- Department of Pathology, Harbor UCLA Medical Center and Los Angeles BioMedical Institute, 1000W, Carson, Torrance, CA 90509, United States
| | - S W French
- Department of Pathology, Harbor UCLA Medical Center and Los Angeles BioMedical Institute, 1000W, Carson, Torrance, CA 90509, United States.
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12
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Perova T, Grandal I, Nutter LMJ, Papp E, Matei IR, Beyene J, Kowalski PE, Hitzler JK, Minden MD, Guidos CJ, Danska JS. Therapeutic potential of spleen tyrosine kinase inhibition for treating high-risk precursor B cell acute lymphoblastic leukemia. Sci Transl Med 2014; 6:236ra62. [PMID: 24828076 DOI: 10.1126/scitranslmed.3008661] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Intensified and central nervous system (CNS)-directed chemotherapy has improved outcomes for pediatric B cell acute lymphoblastic leukemia (B-ALL) but confers treatment-related morbidities. Moreover, many patients suffer relapses, underscoring the need to develop new molecular targeted B-ALL therapies. Using a mouse model, we show that leukemic B cells require pre-B cell receptor (pre-BCR)-independent spleen tyrosine kinase (SYK) signaling in vivo for survival and proliferation. In diagnostic samples from human pediatric and adult B-ALL patients, SYK and downstream targets were phosphorylated regardless of pre-BCR expression or genetic subtype. Two small-molecule SYK inhibitors, fostamatinib and BAY61-3606, attenuated the growth of 69 B-ALL samples in vitro, including high-risk (HR) subtypes. Orally administered fostamatinib reduced heavy disease burden after xenotransplantation of HR B-ALL samples into immunodeficient mice and decreased leukemia dissemination into spleen, liver, kidneys, and the CNS of recipient mice. Thus, SYK activation sustains the growth of multiple HR B-ALL subtypes, suggesting that SYK inhibitors may improve outcomes for HR and relapsed B-ALL.
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Affiliation(s)
- Tatiana Perova
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada. Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Ildiko Grandal
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada
| | - Lauryl M J Nutter
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada
| | - Eniko Papp
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada. Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Irina R Matei
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada. Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Joseph Beyene
- Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Paul E Kowalski
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada
| | - Johann K Hitzler
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada. Division of Haematology/Oncology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada
| | - Mark D Minden
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5S 1A8, Canada. Ontario Cancer Institute and Princess Margaret Hospital, University Health Network, Toronto, Ontario M5T 2M9, Canada
| | - Cynthia J Guidos
- Program in Developmental and Stem Cell Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada. Department of Immunology, University of Toronto, Toronto, Ontario M5S 1A8, Canada
| | - Jayne S Danska
- Department of Medical Biophysics, University of Toronto, Toronto, Ontario M5S 1A8, Canada. Program in Genetics & Genome Biology, The Hospital for Sick Children, Toronto, Ontario M5G 1L7, Canada.
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13
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Krisenko MO, Geahlen RL. Calling in SYK: SYK's dual role as a tumor promoter and tumor suppressor in cancer. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1853:254-63. [PMID: 25447675 DOI: 10.1016/j.bbamcr.2014.10.022] [Citation(s) in RCA: 94] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2014] [Revised: 10/21/2014] [Accepted: 10/27/2014] [Indexed: 12/18/2022]
Abstract
SYK (spleen tyrosine kinase) is well-characterized in the immune system as an essential enzyme required for signaling through multiple classes of immune recognition receptors. As a modulator of tumorigenesis, SYK has a bit of a schizophrenic reputation, acting in some cells as a tumor promoter and in others as a tumor suppressor. In many hematopoietic malignancies, SYK provides an important survival function and its inhibition or silencing frequently leads to apoptosis. In cancers of non-immune cells, SYK provides a pro-survival signal, but can also suppress tumorigenesis by restricting epithelial-mesenchymal transition, enhancing cell-cell interactions and inhibiting migration.
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Affiliation(s)
- Mariya O Krisenko
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue Center for Cancer Research, Purdue University, West Lafayette, IN 47907, United States
| | - Robert L Geahlen
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue Center for Cancer Research, Purdue University, West Lafayette, IN 47907, United States.
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14
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A PREVIOUSLY UNKNOWN UNIQUE CHALLENGE FOR INHIBITORS OF SYK ATP-BINDING SITE: ROLE OF SYK AS A CELL CYCLE CHECKPOINT REGULATOR. EBioMedicine 2014; 1:16-28. [PMID: 25506060 PMCID: PMC4259291 DOI: 10.1016/j.ebiom.2014.10.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
The identification of SYK as a molecular target in B-lineage leukemia/lymphoma cells prompted the development of SYK inhibitors as a new class of anti-cancer drug candidates. Here we report that induction of the SYK gene expression in human cells causes a significant down-regulation of evolutionarily conserved genes associated with mitosis and cell cycle progression providing unprecedented evidence that SYK is a master regulator of cell cycle regulatory checkpoint genes in human cells. We further show that SYK regulates the G2 checkpoint by physically associating with and inhibiting the dual-specificity phosphatase CDC25C via phosphorylation of its S216 residue. SYK depletion by RNA interference or treatment with the chemical SYK inhibitor prevented nocodazole-treated human cell lines from activating the G2 checkpoint via CDC25C S216-phosphorylation and resulted in polyploidy. Our study provides genetic and biochemical evidence that spleen tyrosine kinase (SYK) has a unique role in the activation of the G2 checkpoint in both non-lymphohematopoietic and B-lineage lymphoid cells. This previously unknown role of SYK as a cell cycle checkpoint regulator represents an unforeseen and significant challenge for inhibitors of SYK ATP binding site. SYK is a cell cycle regulatory kinase that phosphorylates CDC25C at S216 SYK is a master regulator of cell cycle regulatory checkpoint genes in human cells Inhibitors of SYK ATP binding site may increase the risk for secondary cancer
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15
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Exon expression QTL (eeQTL) analysis highlights distant genomic variations associated with splicing regulation. QUANTITATIVE BIOLOGY 2014. [DOI: 10.1007/s40484-014-0031-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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16
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Feng H, Qin Z, Zhang X. Opportunities and methods for studying alternative splicing in cancer with RNA-Seq. Cancer Lett 2013. [DOI: 10.1016/j.canlet.2012.11.010] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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17
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Abstract
We report preclinical proof of principle for effective treatment of B-precursor acute lymphoblastic leukemia (ALL) by targeting the spleen tyrosine kinase (SYK)-dependent antiapoptotic blast cell survival machinery with a unique nanoscale pharmaceutical composition. This nanoscale liposomal formulation (NLF) contains the pentapeptide mimic 1,4-Bis (9-O dihydroquinidinyl) phthalazine/hydroquinidine 1,4-phathalazinediyl diether (C61) as the first and only selective inhibitor of the substrate binding P-site of SYK. The C61 NLF exhibited a very favorable pharmacokinetic and safety profile in mice, induced apoptosis in primary B-precursor ALL blast cells taken directly from patients as well as in vivo clonogenic ALL xenograft cells, destroyed the in vivo clonogenic fraction of ALL blast cells, and, at nontoxic dose levels, exhibited potent in vivo antileukemic activity against patient-derived ALL cells in xenograft models of aggressive B-precursor ALL. Our findings establish SYK as an attractive molecular target for therapy of B-precursor ALL. Further development of the C61 NLF may provide the foundation for therapeutic innovation against therapy-refractory B-precursor ALL.
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18
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Tyner JW. Rapid Identification of Therapeutic Targets in Hematologic Malignancies via Functional Genomics. Ther Adv Hematol 2013; 2:83-93. [PMID: 23556079 DOI: 10.1177/2040620711403028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The clinical application of gene-targeted drugs has transformed cancer therapy. The hallmark example of this strategy is use of the ABL kinase inhibitor imatinib for treatment of patients with chronic myeloid leukemia (CML). This remarkable clinical success has also stimulated an expansive search for personalized gene targets in all patients to facilitate broad application of targeted therapy for cancer. However, achievement of this objective will require simultaneous work towards several complementary goals. The first step towards broad application of gene-targeted therapy must entail a rapid means to identify target oncogenes in individual patients. Next, we must identify well-tolerated, gene-specific drugs that are collectively effective against a wide diversity of gene targets. Finally, we must develop protocols by which individual patients are matched with appropriate, gene-targeted drugs in a clinically relevant time frame. While these may seem like difficult tasks, we are fortunate to have a wide variety of new and rapidly evolving research tools at our disposal. These include next-generation sequencing of the genome and transcriptome, single nucleotide polymorphism (SNP)/copy number variations (CNV) and gene expression microarrays, and RNAi libraries for the application of functional screens. In this review we discuss the advantages and disadvantages of each of these techniques with the goal of demonstrating that no single technique will be sufficient as a standalone technology, but rather it will be the integration of all techniques that will enable broad application of gene-targeted cancer therapies.
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β2 integrin-derived signals induce cell survival and proliferation of AML blasts by activating a Syk/STAT signaling axis. Blood 2013; 121:3889-99, S1-66. [PMID: 23509157 DOI: 10.1182/blood-2012-09-457887] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Spleen tyrosine kinase (Syk) induces cell survival and proliferation in a high proportion of acute myeloid leukemia (AML) blasts, but the underlying molecular events of Syk signaling have not been investigated. Proteomic techniques have allowed us to identify the multiprotein complex that is nucleated by constitutively active Syk in AML cells. This complex differs from the B-lymphoid Syk interactome with respect to several proteins, especially the integrin receptor Mac-1, the Fc-γ receptor I (FcγRI), and the transcription factors STAT3 and STAT5. We show in several AML cell line models that tonic signals derived from the Fc-γ chain lead to Syk-dependent activation of STAT3 and STAT5, which in turn induces cell survival and proliferation. Moreover, stimulation of Mac-1 or FcγRI intensifies the constitutive Syk-mediated STAT3/5 activation in AML cells, a scenario likely to take place in the bone marrow niche. In accordance with these findings, we observed that β2 integrins, including Mac-1, trigger proliferation of AML cells in an AML cell/stroma coculture model. Taken together, we identified an oncogenic integrin/Syk/STAT3/5 signaling axis that might serve as a therapeutic target of AML in the future.
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20
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Kelly V, Genovese M. Novel small molecule therapeutics in rheumatoid arthritis. Rheumatology (Oxford) 2013; 52:1155-62. [DOI: 10.1093/rheumatology/kes367] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
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21
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Serine phosphorylation by SYK is critical for nuclear localization and transcription factor function of Ikaros. Proc Natl Acad Sci U S A 2012; 109:18072-7. [PMID: 23071339 DOI: 10.1073/pnas.1209828109] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ikaros is a zinc finger-containing DNA-binding protein that plays a pivotal role in immune homeostasis through transcriptional regulation of the earliest stages of lymphocyte ontogeny and differentiation. Functional deficiency of Ikaros has been implicated in the pathogenesis of acute lymphoblastic leukemia, the most common form of childhood cancer. Therefore, a stringent regulation of Ikaros activity is considered of paramount importance, but the operative molecular mechanisms responsible for its regulation remain largely unknown. Here we provide multifaceted genetic and biochemical evidence for a previously unknown function of spleen tyrosine kinase (SYK) as a partner and posttranslational regulator of Ikaros. We demonstrate that SYK phoshorylates Ikaros at unique C-terminal serine phosphorylation sites S358 and S361, thereby augmenting its nuclear localization and sequence-specific DNA binding activity. Mechanistically, we establish that SYK-induced Ikaros activation is essential for its nuclear localization and optimal transcription factor function.
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22
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Quantitative phosphoproteomics revealed interplay between Syk and Lyn in the resistance to nilotinib in chronic myeloid leukemia cells. Blood 2011; 118:2211-21. [DOI: 10.1182/blood-2010-10-313692] [Citation(s) in RCA: 79] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Abstract
In this study, we have addressed how Lyn kinase signaling mediates nilotinib-resistance by quantitative phospho-proteomics using Stable Isotope Labeling with Amino acid in Cell culture. We have found an increased tyrosine phosphorylation of 2 additional tyrosine kinases in nilotinib-resistant cells: the spleen tyrosine kinase Syk and the UFO family receptor tyrosine kinase Axl. This increased tyrosine phosphorylation involved an interaction of these tyrosine kinases with Lyn. Inhibition of Syk by the inhibitors R406 or BAY 61-3606 or by RNA interference restored the capacity of nilotinib to inhibit cell proliferation. Conversely, coexpression of Lyn and Syk were required to fully induce resistance to nilotinib in drug-sensitive cells. Surprisingly, the knockdown of Syk also strongly decreased tyrosine phosphorylation of Lyn and Axl, thus uncovering interplay between Syk and Lyn. We have shown the involvement of the adaptor protein CDCP-1 in resistance to nilotinib. Interestingly, the expression of Axl and CDCP1 were found increased both in a nilotinib-resistant cell line and in nilotinib-resistant CML patients. We conclude that an oncogenic signaling mediated by Lyn and Syk can bypass the need of Bcr-Abl in CML cells. Thus, targeting these kinases may be of therapeutic value to override imatinib or nilotinib resistance in CML.
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Bohnenberger H, Oellerich T, Engelke M, Hsiao HH, Urlaub H, Wienands J. Complex phosphorylation dynamics control the composition of the Syk interactome in B cells. Eur J Immunol 2011; 41:1550-62. [PMID: 21469132 DOI: 10.1002/eji.201041326] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2010] [Revised: 03/14/2011] [Accepted: 03/25/2011] [Indexed: 11/08/2022]
Abstract
Spleen tyrosine kinase Syk provides critical transducer functions for a number of immune cell receptors and has been implicated in the generation of several forms of leukemias. Catalytic activity and the ability of Syk to interact with other signaling elements depend on the phosphorylation status of Syk. We have now identified and quantified the full spectrum of phosphoacceptor sites in human Syk as well as the interactome of Syk in resting and activated B cells by high-resolution mass spectrometry. While the majority of inducible phosphorylations occurred on tyrosine residues, one of the most frequently detected phosphosites encompassed serine 297 located within the linker insert distinguishing the long and short isoforms of Syk. Full-length Syk can associate with more than 25 distinct ligands including the 14-3-3γ adaptor protein, which binds directly to phosphoserine 297. The latter complex attenuates inducible plasma membrane recruitment of Syk, thereby limiting antigen receptor-proximal signaling pathways. Collectively, the established ligand library provides a basis to understand the complexity of the Syk signaling network.
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Affiliation(s)
- Hanibal Bohnenberger
- Georg August University of Göttingen, Institute of Cellular and Molecular Immunology, Humboldtallee, Göttingen, Germany
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24
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Alternative splicing of SYK regulates mitosis and cell survival. Nat Struct Mol Biol 2011; 18:673-9. [PMID: 21552259 DOI: 10.1038/nsmb.2040] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 02/17/2011] [Indexed: 12/15/2022]
Abstract
Most human genes produce multiple mRNA isoforms through alternative splicing. However, the biological relevance of most splice variants remains unclear. In this study, we evaluated the functional impact of alternative splicing in cancer cells. We modulated the splicing pattern of 41 cancer-associated splicing events and scored the effects on cell growth, viability and apoptosis, identifying three isoforms essential for cell survival. Specifically, changing the splicing pattern of the spleen tyrosine kinase gene (SYK) impaired cell-cycle progression and anchorage-independent growth. Notably, exposure of cancer cells to epithelial growth factor modulated the SYK splicing pattern to promote the pro-survival isoform that is associated with cancer tissues in vivo. The data suggest that splicing of selected genes is specifically modified during tumor development to allow the expression of isoforms that promote cancer cell survival.
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25
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Murakami H, Kuroiwa T, Suzuki K, Miura Y, Sentsui H. Analysis of Syk expression in bovine lymphoma and persistent lymphocytosis induced by bovine leukemia virus. J Vet Med Sci 2010; 73:41-5. [PMID: 20736517 DOI: 10.1292/jvms.10-0225] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Spleen tyrosine kinase (Syk) is closely related to various cell reactions. In B-cells, Syk is involved in early B-cell receptor signaling, which affects cellular survival, proliferation and differentiation. Although the kinetics of Syk mRNA and its activity are variable in different types of tumor cells, Syk may have a relation to tumor progression in many human tumors, including B-cell lymphoma/leukemia. In this study we examined whether Syk mRNA expression was changed in bovine leukemia virus (BLV)-induced persistent lymphocytosis (PL) and lymphoma. As a result, we demonstrated that the Syk mRNA expression was significantly increased in PL samples, whereas it was decreased in tumor samples. Moreover one cow, which Syk mRNA expression has been lowest among PL cattle, developed lymphoma three months later and the expression significantly decreased. These data suggest that Syk mRNA expression dynamics is closely related to BLV-induced disease.
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Affiliation(s)
- Hironobu Murakami
- Laboratory of Veterinary Epizootiology, School of Veterinary Medicine, Nihon University, Kanagawa, Japan
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26
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Mócsai A, Ruland J, Tybulewicz VLJ. The SYK tyrosine kinase: a crucial player in diverse biological functions. Nat Rev Immunol 2010; 10:387-402. [PMID: 20467426 PMCID: PMC4782221 DOI: 10.1038/nri2765] [Citation(s) in RCA: 925] [Impact Index Per Article: 66.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Spleen tyrosine kinase (SYK) is known to have a crucial role in adaptive immune receptor signalling. However, recent reports indicate that SYK also mediates other, unexpectedly diverse biological functions, including cellular adhesion, innate immune recognition, osteoclast maturation, platelet activation and vascular development. SYK is activated by C-type lectins and integrins, and activates new targets, including the CARD9-BCL-10-MALT1 pathway and the NLRP3 inflammasome. Studies using Drosophila melanogaster suggest that there is an evolutionarily ancient origin of SYK-mediated signalling. Moreover, SYK has a crucial role in autoimmune diseases and haematological malignancies. This Review summarizes our current understanding of the diverse functions of SYK and how this is being translated for therapeutic purposes.
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Affiliation(s)
- Attila Mócsai
- Department of Physiology, Semmelweis University School of Medicine, 1094 Budapest, Hungary.
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27
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Uckun FM, Ek RO, Jan ST, Chen CL, Qazi S. Targeting SYK kinase-dependent anti-apoptotic resistance pathway in B-lineage acute lymphoblastic leukaemia (ALL) cells with a potent SYK inhibitory pentapeptide mimic. Br J Haematol 2010; 149:508-17. [PMID: 20151979 DOI: 10.1111/j.1365-2141.2010.08106.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The present study found that the pentapeptide mimic C-61, targeting the substrate binding P-site of SYK tyrosine kinase acted as a potent inducer of apoptosis in chemotherapy-resistant SYK-expressing primary leukemic B-cell precursors taken directly from relapsed B-precursor leukaemia (BPL) patients (but not SYK-deficient infant pro-B leukaemia cells), exhibited favourable pharmacokinetics in mice and non-human primates, and eradicated in vivo clonogenic leukaemia cells in severe combined immunodeficient mouse xenograft models of chemotherapy-resistant human BPL at dose levels non-toxic to mice and non-human primates. These in vitro and in vivo findings provide proof of principle for effective treatment of chemotherapy-resistant BPL by targeting SYK-dependent anti-apoptotic blast cell survival machinery with a SYK P-Site inhibitor. Further development of C-61 may provide the foundation for therapeutic innovation against chemotherapy-resistant BPL.
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Affiliation(s)
- Fatih M Uckun
- Developmental Therapeutics Program, Institute for Peadiatric Clinical Research, Childrens Hospital Los Angeles, and Department of Pediatrics, University of Southern California, Keck School of Medicine, Los Angeles, CA 90027-0367, USA.
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28
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STAT3 is a substrate of SYK tyrosine kinase in B-lineage leukemia/lymphoma cells exposed to oxidative stress. Proc Natl Acad Sci U S A 2010; 107:2902-7. [PMID: 20133729 DOI: 10.1073/pnas.0909086107] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
We provide unprecedented genetic and biochemical evidence that the antiapoptotic transcription factor STAT3 serves as a substrate for SYK tyrosine kinase both in vitro and in vivo. Induction of SYK in an ecdysone-inducible mammalian expression system results in STAT3 activation, as documented by tyrosine phosphorylation and nuclear translocation of STAT3, as well as amplified expression of several STAT3 target genes. STAT3 activation after oxidative stress (OS) is strongly diminished in DT40 chicken B-lineage lymphoma cells rendered SYK-deficient by targeted disruption of the syk gene. Introduction of a wild-type, C-terminal or N-terminal SH2 domain-mutated, but not a kinase domain-mutated, syk gene into SYK-deficient DT40 cells restores OS-induced enhancement of STAT-3 activity. Thus, SYK plays an important and indispensable role in OS-induced STAT3 activation and its catalytic SH1 domain is critical for this previously unknown regulatory function. These results provide evidence for the existence of a novel mode of cytokine-independent cross-talk that operates between SYK and STAT3 pathways and regulates apoptosis during OS. We further provide experimental evidence that SYK is capable of associating with and phosphorylating STAT3 in human B-lineage leukemia/lymphoma cells challenged with OS. In agreement with a prerequisite role of SYK in OS-induced STAT3 activation, OS does not induce tyrosine phosphorylation of STAT3 in SYK-deficient human proB leukemia cells. Notably, inhibition of SYK with a small molecule drug candidate prevents OS-induced activation of STAT3 and overcomes the resistance of human B-lineage leukemia/lymphoma cells to OS-induced apoptosis.
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29
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The tyrosine kinase Syk regulates the survival of chronic lymphocytic leukemia B cells through PKCdelta and proteasome-dependent regulation of Mcl-1 expression. Oncogene 2009; 28:3261-73. [PMID: 19581935 DOI: 10.1038/onc.2009.179] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
B-cell chronic lymphocytic leukemia (B-CLL) is characterized by accumulation of mature monoclonal CD5+ B cells. The disease results mainly from a failure of cells to undergo apoptosis, a process largely influenced by the existence of constitutively activated components of B-cell receptor signaling and the deregulated expression of anti-apoptotic molecules. Recent evidence pointing to a critical role of spleen tyrosine kinase (Syk) in ligand-independent BCR signaling prompted us to examine its role in primary B-CLL cell survival. We demonstrate that pharmacological inhibition of constitutive Syk activity and silencing by siRNA led to a dramatic decrease of cell viability in CLL samples (n=44), regardless of clinical and biological status and induced typical apoptotic cell death with mitochondrial failure followed by caspase 3-dependent cell death. We also provide functional and biochemical evidence that Syk regulated B-CLL cell survival through a novel pathway involving PKCdelta and a proteasome-dependent regulation of the anti-apoptotic protein Mcl-1. Together, our observations are consistent with a model wherein PKCdelta downstream of Syk stabilizes Mcl-1 through inhibitory phosphorylation of GSK3 by Akt. We conclude that Syk constitutes a key regulator of B-CLL cell survival, emphasizing the clinical utility of Syk inhibition in hematopoietic malignancies.
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30
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Leeman JR, Gilmore TD. Alternative splicing in the NF-kappaB signaling pathway. Gene 2008; 423:97-107. [PMID: 18718859 DOI: 10.1016/j.gene.2008.07.015] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2008] [Revised: 07/08/2008] [Accepted: 07/09/2008] [Indexed: 10/21/2022]
Abstract
Activation of transcription factor NF-kappaB can affect the expression of several hundred genes, many of which are involved in inflammation and immunity. The proper NF-kappaB transcriptional response is primarily regulated by post-translational modification of NF-kappaB signaling constituents. Herein, we review the accumulating evidence suggesting that alternative splicing of NF-kappaB signaling components is another means of controlling NF-kappaB signaling. Several alternative splicing events in both the tumor necrosis factor and Toll/interleukin-1 NF-kappaB signaling pathways can inhibit the NF-kappaB response, whereas others enhance NF-kappaB signaling. Alternative splicing of mRNAs encoding some NF-kappaB signaling components can be induced by prolonged exposure to an NF-kappaB-activating signal, such as lipopolysaccharide, suggesting a mechanism for negative feedback to dampen excessive NF-kappaB signaling. Moreover, some NF-kappaB alternative splicing events appear to be specific for certain diseases, and could serve as therapeutic targets or biomarkers.
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Affiliation(s)
- Joshua R Leeman
- Department of Biology, Boston University, 5 Cummington Street, Boston, MA 02215, USA
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31
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Inubushi S, Nagano-Fujii M, Kitayama K, Tanaka M, An C, Yokozaki H, Yamamura H, Nuriya H, Kohara M, Sada K, Hotta H. Hepatitis C virus NS5A protein interacts with and negatively regulates the non-receptor protein tyrosine kinase Syk. J Gen Virol 2008; 89:1231-1242. [PMID: 18420802 DOI: 10.1099/vir.0.83510-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Hepatitis C virus (HCV) is the major causative agent of hepatocellular carcinoma. However, the precise mechanism underlying the carcinogenesis is yet to be elucidated. It has recently been reported that Syk, a non-receptor protein tyrosine kinase, functions as a potent tumour suppressor in human breast carcinoma. This study first examined the possible effect of HCV infection on expression of Syk in vivo. Immunohistochemical analysis revealed that endogenous Syk, which otherwise was expressed diffusely in the cytoplasm of normal hepatocytes, was localized near the cell membrane with a patchy pattern in HCV-infected hepatocytes. The possible interaction between HCV proteins and Syk in human hepatoma-derived Huh-7 cells was then examined. Immunoprecipitation analysis revealed that NS5A interacted strongly with Syk. Deletion-mutation analysis revealed that an N-terminal portion of NS5A (aa 1-175) was involved in the physical interaction with Syk. An in vitro kinase assay demonstrated that NS5A inhibited the enzymic activity of Syk and that, in addition to the N-terminal 175 residues, a central portion of NS5A (aa 237-302) was required for inhibition of Syk. Moreover, Syk-mediated phosphorylation of phospholipase C-gamma1 was downregulated by NS5A. An interaction of NS5A with Syk was also detected in Huh-7.5 cells harbouring an HCV RNA replicon or infected with HCV. In conclusion, these results demonstrated that NS5A interacts with Syk resulting in negative regulation of its kinase activity. The results indicate that NS5A may be involved in the carcinogenesis of hepatocytes through the suppression of Syk kinase activities.
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Affiliation(s)
- Sachiko Inubushi
- Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Motoko Nagano-Fujii
- Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Kikumi Kitayama
- Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Motofumi Tanaka
- Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Chunying An
- Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Hiroshi Yokozaki
- Division of Surgical Pathology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Hirohei Yamamura
- Hyogo Laboratory, Hyogo Prefectural Institute of Public Health and Environmental Sciences, Kobe 652-0032, Japan
| | - Hideko Nuriya
- Department of Microbiology and Cell Biology, The Tokyo Metropolitan Institute of Medical Science, Tokyo 113-8613, Japan
| | - Michinori Kohara
- Department of Microbiology and Cell Biology, The Tokyo Metropolitan Institute of Medical Science, Tokyo 113-8613, Japan
| | - Kiyonao Sada
- Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
| | - Hak Hotta
- Division of Microbiology, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
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WANDROO F, BELL A, DARBYSHIRE P, PRATT G, STANKOVIC T, GORDON J, LAWSON S, MOSS P. ZAP-70 is highly expressed in most cases of childhood pre-B cell acute lymphoblastic leukemia. Int J Lab Hematol 2008; 30:149-57. [DOI: 10.1111/j.1751-553x.2007.00915.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Wossning T, Herzog S, Köhler F, Meixlsperger S, Kulathu Y, Mittler G, Abe A, Fuchs U, Borkhardt A, Jumaa H. Deregulated Syk inhibits differentiation and induces growth factor-independent proliferation of pre-B cells. ACTA ACUST UNITED AC 2006; 203:2829-40. [PMID: 17130299 PMCID: PMC2118175 DOI: 10.1084/jem.20060967] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The nonreceptor protein spleen tyrosine kinase (Syk) is a key mediator of signal transduction in a variety of cell types, including B lymphocytes. We show that deregulated Syk activity allows growth factor–independent proliferation and transforms bone marrow–derived pre–B cells that are then able to induce leukemia in mice. Syk-transformed pre–B cells show a characteristic pattern of tyrosine phosphorylation, increased c-Myc expression, and defective differentiation. Treatment of Syk-transformed pre–B cells with a novel Syk-specific inhibitor (R406) reduces tyrosine phosphorylation and c-Myc expression. In addition, R406 treatment removes the developmental block and allows the differentiation of the Syk-transformed pre–B cells into immature B cells. Because R406 treatment also prevents the proliferation of c-Myc–transformed pre–B cells, our data indicate that endogenous Syk kinase activity may be required for the survival of pre–B cells transformed by other oncogenes. Collectively, our data suggest that Syk is a protooncogene involved in the transformation of lymphocytes, thus making Syk a potential target for the treatment of leukemia.
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Affiliation(s)
- Thomas Wossning
- Institute of Biology III, Albert-Ludwigs-University of Freiburg, 79104 Freiburg, and Department of Pediatric Hematology and Oncology, Children's Hospital, Munich, Germany
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34
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Balaian L, Ball ED. Cytotoxic activity of gemtuzumab ozogamicin (Mylotarg) in acute myeloid leukemia correlates with the expression of protein kinase Syk. Leukemia 2006; 20:2093-101. [PMID: 17051243 DOI: 10.1038/sj.leu.2404437] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Acute myeloid leukemia (AML) cells express the cell surface antigen CD33 that, upon ligation with a monoclonal antibody (mAb), is a downregulator of cell growth in a Syk-dependent manner. An anti-CD33 mAb coupled to a toxin, gemtuzumab ozogamicin (GO), is used for the treatment of AML (Mylotarg). Therefore, we investigated whether the response of AML cells to GO treatment also depends on Syk expression. Forty primary AML samples (25 Syk-positive and 15 Syk-negative) were tested for their response to the anti-proliferative effects of GO and unmodified anti-CD33 mAb. A correlation between Syk expression and the response of leukemia cells to GO and anti-CD33 mAb was found. 'Blocking' of Syk by small interfering RNA resulted in unresponsiveness of AML cells to both GO and anti-CD33 mAb-mediated cytotoxicity. Syk upregulation by the de-methylating agent 5-azacytidine (5-aza) induced re-expression of Syk in some cases, resulting in enhanced GO and anti-CD33-mediated inhibition of leukemia cell growth. Thus, the cytotoxicity of both GO and anti-CD33 in primary AML samples was associated with Syk expression. 5-Aza restored Syk and increased the sensitivity of originally Syk-negative, non-responsive cells to CD33 ligation to levels of Syk-positive cells. These data have clinical significance for predicting response to GO and designing clinical trials.
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MESH Headings
- Aminoglycosides/pharmacology
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal, Humanized
- Antigens, CD/immunology
- Antigens, Differentiation, Myelomonocytic/immunology
- Antineoplastic Agents/pharmacology
- Azacitidine/pharmacology
- Cell Line, Tumor
- Gemtuzumab
- Humans
- Immunotoxins/pharmacology
- Intracellular Signaling Peptides and Proteins/analysis
- Intracellular Signaling Peptides and Proteins/antagonists & inhibitors
- Leukemia, Myeloid, Acute/drug therapy
- Leukemia, Myeloid, Acute/enzymology
- Leukemia, Myeloid, Acute/pathology
- Protein-Tyrosine Kinases/analysis
- Protein-Tyrosine Kinases/antagonists & inhibitors
- RNA, Small Interfering
- Sialic Acid Binding Ig-like Lectin 3
- Syk Kinase
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Affiliation(s)
- L Balaian
- Blood and Marrow Transplantation Division, Department of Medicine and Moores UCSD Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA
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35
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Crespo M, Villamor N, Giné E, Muntañola A, Colomer D, Marafioti T, Jones M, Camós M, Campo E, Montserrat E, Bosch F. ZAP-70 expression in normal pro/pre B cells, mature B cells, and in B-cell acute lymphoblastic leukemia. Clin Cancer Res 2006; 12:726-34. [PMID: 16467082 DOI: 10.1158/1078-0432.ccr-05-1531] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE The ZAP-70 gene is normally expressed in T and natural killer cells, where it is required for the T-cell receptor (TCR) signaling. More recently, it has been described that ZAP-70 contributes to the B-cell development at early stages of B-cell differentiation in mice. The purpose was to investigate the presence of ZAP-70 in normal pro/pre B cells and mature B cells and in tumoral cells from B-acute lymphoblastic leukemias (B-ALL). EXPERIMENTAL DESIGN ZAP-70 expression was ascertained by flow cytometry, immunofluorescence, Western blot, and quantitative reverse transcription-PCR. Analysis of ZAP-70 and other signaling proteins of the pre-TCR/TCR was done by Western blot. RESULTS ZAP-70 was expressed in pro/pre B cells but not in normal mature B cells derived from bone marrow, peripheral blood, or tonsil. Among tumoral cells, ZAP-70 was expressed in 56% of B-ALLs with pro/pre B-cell phenotype and in 4 of 6 Burkitt/ALL lymphomas. In B-ALL cells, expression of CD38 protein correlated with ZAP-70 expression (P = 0.05). Mutational analysis of the ZAP-70 gene revealed the absence of mutations in cases lacking ZAP-70 expression. Moreover, other elements of the pre-TCR/TCR signaling pathway, like LAT and Lck, were also found in B-ALL cells. CONCLUSIONS Among normal B-cell subsets, ZAP-70 was found expressed in normal pro/pre B cells but not in a significant proportion of normal B cells with mature phenotype. Moreover, the presence of ZAP-70 in B-ALLs probably reflects their cellular origin. The lack of ZAP-70 expression in normal mature B cells suggests that its expression in mature-derived neoplasms with different cellular origin, such as Burkitt's lymphoma and chronic lymphocytic leukemia, might be due to an aberrant phenomenon.
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Affiliation(s)
- Marta Crespo
- Department of Hematology, Institut d'Investigacions Biomèdiques August Pi i Sunyer, Hospital Clínic, Barcelona, Spain
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36
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Abstract
Alternative pre-mRNA splicing leads to distinct products of gene expression in development and disease. Antagonistic splice variants of genes involved in differentiation, apoptosis, invasion and metastasis often exist in a delicate equilibrium that is found to be perturbed in tumours. In several recent examples, splice variants that are overexpressed in cancer are expressed as hyper-oncogenic proteins, which often correlate with poor prognosis, thus suggesting improved diagnosis and follow up treatment. Global gene expression technologies are just beginning to decipher the interplay between alternatively spliced isoforms and protein-splicing factors that will lead to identification of the mutations in these trans-acting factors responsible for pathogenic alternative splicing in cancer.
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Affiliation(s)
- Julian P Venables
- University of Newcastle-upon-Tyne, Institute of Human Genetics, International Centre for Life, Central Parkway, Newcastle-upon-Tyne, UK.
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37
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Hendriks RW, Kersseboom R. Involvement of SLP-65 and Btk in tumor suppression and malignant transformation of pre-B cells. Semin Immunol 2006; 18:67-76. [PMID: 16300960 DOI: 10.1016/j.smim.2005.10.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Signals from the precursor-B cell receptor (pre-BCR) are essential for selection and clonal expansion of pre-B cells that have performed productive immunoglobulin heavy chain V(D)J recombination. In the mouse, the downstream signaling molecules SLP-65 and Btk cooperate to limit proliferation and induce differentiation of pre-B cells, thereby acting as tumor suppressors to prevent pre-B cell leukemia. In contrast, recent observations in human BCR-ABL1(+) pre-B lymphoblastic leukemia cells demonstrate that Btk is constitutively phosphorylated and activated by the BCR-ABL1 fusion protein. As a result, activated Btk transmits survival signals that are essential for the transforming activity of oncogenic Abl tyrosine kinase.
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Affiliation(s)
- Rudi W Hendriks
- Department of Immunology, Erasmus MC Rotterdam, P.O. Box 1738, NL-3000 DR Rotterdam, The Netherlands.
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38
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Coopman PJ, Mueller SC. The Syk tyrosine kinase: a new negative regulator in tumor growth and progression. Cancer Lett 2006; 241:159-73. [PMID: 16442709 DOI: 10.1016/j.canlet.2005.11.004] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2005] [Revised: 11/03/2005] [Accepted: 11/04/2005] [Indexed: 11/28/2022]
Abstract
The spleen tyrosine kinase Syk was long thought to be a hematopoietic cell-specific signaling molecule. Recent evidence demonstrated that it is also expressed by many non-hematopoietic cell types and that it plays a negative role in cancer. A significant drop in its expression was first observed during breast cancer progression, but an anomalous Syk expression has now also been evidenced in many other tumor types. Mechanistic studies using Syk re-expression demonstrated its suppressive function in tumorigenesis and metastasis formation, which is surprising for a tyrosine kinase. Loss of Syk expression is regulated, albeit not exclusively, by its promoter hypermethylation. The molecular mechanism of its tumor-suppressive function remains largely unknown; the identification of its activators and effectors in non-hematopoietic cells will be a challenge for the years to come. An increasing number of clinical studies reveal a correlation between reduced Syk expression and an increased risk for metastasis formation, and assign Syk as a potential new prognostic marker in different tumor types.
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Affiliation(s)
- Peter J Coopman
- CNRS UMR 5539, Université Montpellier 2, 34095 Montpellier, France.
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39
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Zyss D, Montcourrier P, Vidal B, Anguille C, Mérezègue F, Sahuquet A, Mangeat PH, Coopman PJ. The Syk tyrosine kinase localizes to the centrosomes and negatively affects mitotic progression. Cancer Res 2006; 65:10872-80. [PMID: 16322234 DOI: 10.1158/0008-5472.can-05-1270] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We showed previously that the spleen tyrosine kinase Syk is expressed by mammary epithelial cells and that it suppresses malignant growth of breast cancer cells. The exact molecular mechanism of its tumor-suppressive activity remains, however, to be identified. Here, we show that Syk colocalizes and copurifies with the centrosomal component gamma-tubulin and exhibits a catalytic activity within the centrosomes. Moreover, its centrosomal localization depends on its intact kinase activity. Centrosomal Syk expression is persistent in interphase but promptly drops during mitosis, obviously resulting from its ubiquitinylation and proteasomal degradation. Conversely, unrestrained exogenous expression of a fluorescently tagged Discosoma sp. red fluorescent protein (DsRed)-Syk chimera engenders abnormal cell division and cell death. Transient DsRed-Syk overexpression triggers an abrupt cell death lacking hallmarks of classic apoptosis but reminiscent of mitotic catastrophe. Surviving stable DsRed-Syk-transfected cells exhibit multipolar mitotic spindles and contain multiple abnormally sized nuclei and supernumerary centrosomes, revealing anomalous cell division. Taken together, these results show that Syk is a novel centrosomal kinase that negatively affects cell division. Its expression is strictly controlled in a spatiotemporal manner, and centrosomal Syk levels need to decline to allow customary progression of mitosis.
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Affiliation(s)
- Déborah Zyss
- Centre National de la Recherche Scientifique UMR5539, Université Montpellier II, Montpellier, France
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40
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Abstract
The proliferation and differentiation of lymphocytes are regulated by receptors localized on the cell surface. Engagement of these receptors induces the activation of intracellular signaling proteins that transmit the receptor signals to distinct targets and control the cellular responses. The first signaling proteins to be discovered in higher organisms were the products of oncogenes. For example, the kinases Src and Abelson (Abl) were originally identified as oncogenes and were later characterized as important proteins for signal transduction in various cell types, including lymphocytes. Now, as many cellular signaling molecules have been discovered and ordered into certain pathways, we can better understand why particular signaling proteins are associated with tumorigenesis. In this review, we discuss recent progress in unraveling the molecular mechanisms of signaling pathways that control the proliferation and differentiation of early B cells. We point out the concepts of auto-inhibition and subcellular localization as crucial aspects in the regulation of B cell signaling.
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Affiliation(s)
- Hassan Jumaa
- Institute for Biology III, Albert-Ludwigs University of Freiburg and Max Planck Institute for Immunobiology, 79108 Freiburg, Germany.
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41
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Matsusaka S, Tohyama Y, He J, Shi Y, Hazama R, Kadono T, Kurihara R, Tohyama K, Yamamura H. Protein-tyrosine kinase, Syk, is required for CXCL12-induced polarization of B cells. Biochem Biophys Res Commun 2005; 328:1163-9. [PMID: 15707999 DOI: 10.1016/j.bbrc.2005.01.076] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2004] [Indexed: 11/23/2022]
Abstract
Cell polarization and migration in response to CXCL12 is essential for hematopoiesis. To investigate the role of Syk in CXCL12/CXCR4-induced signaling, wild-type Syk or its dominant-negative form (DN-Syk) was introduced in mouse pro-B cells, BAF3. With CXCL12 stimulation, BAF3 cells became polarized with the formation of a leading edge and contractile uropod at the rear end with increased motility. Overexpression of wild-type Syk caused enhanced polarization, whereas DN-Syk inhibited cell polarity due to the loss of contractile structure at the rear end, and the altered phenotype was enhanced after CXCL12 stimulation. Motility of mutant BAF3 containing DN-Syk increased independent of CXCL12 stimulation. As beta1 integrin-mediated cell adhesion was inhibited, decreased adhesion might promote motility. CXCL12 stimulation led to prompt activation of RhoA, but expression of DN-Syk suppressed RhoA activation. These results demonstrate that Syk participates in CXCL12-induced cell polarization, which occurs in concert with cell adhesion mediated by beta1 integrin.
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Affiliation(s)
- Satoshi Matsusaka
- Department of Genome Sciences, Kobe University Graduate School of Medicine, Kobe 650-0017, Japan
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42
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Balaian L, Ball ED. Anti-CD33 monoclonal antibodies enhance the cytotoxic effects of cytosine arabinoside and idarubicin on acute myeloid leukemia cells through similarities in their signaling pathways. Exp Hematol 2005; 33:199-211. [PMID: 15676214 DOI: 10.1016/j.exphem.2004.11.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2004] [Revised: 10/28/2004] [Accepted: 11/08/2004] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Chemotherapy agents (CA) such as cytosine arabinoside (ara-C), idarubicin (IDA), and etoposide (VP-16) are widely used in the treatment of acute myeloid leukemia (AML) However, their effects on signaling pathways leading to cytotoxicity have only been described recently. Ligation of the leukemia-associated antigen CD33 by anti-CD33 monoclonal antibody (mAb) also results in signaling events that induce a downregulation of cell growth. We examined the possibility that anti-CD33 mAb and CA might cooperate in mediation of growth inhibition in primary AML samples and AML cell lines. MATERIALS AND METHODS We investigated two AML cells lines and 14 primary AML samples for their proliferative response ((3)H-thymidine incorporation), colony formation, and biochemical (Western blot analysis) to anti-CD33 mAb treatment combined with chemotherapy agents. RESULTS CD33 ligation induced a significant increase in ara-C- or IDA- but not VP-16-or Bryostatin-mediated inhibition of proliferation and colony formation. Ara-C and IDA induced SHP-1 and SHP-2 protein tyrosine phosphatase (PTPs) phosphorylation and Lyn/SHP-1 complex formation, while VP-16 and Bryostatin did not. CD33 ligation, however, mediated phosphorylation of these PTPs and Syk/SHP-1 complex formations. Combined treatment of AML cells by ara-C or IDA with anti-CD33 mAb resulted in higher levels of SHP-1 phosphorylation. Reduction in SHP-1 by short interfering RNA abrogated these effects. CONCLUSION These data suggest that combined incubation of leukemia cells with anti-CD33 mAb and ara-C or IDA, but not VP-16 or Bryostatin, independently triggers similar events in the downstream signaling cascade, and therefore leads to additive antiproliferative effects and enhanced cytotoxicity.
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Affiliation(s)
- Larisa Balaian
- Department of Medicine and Moores UCSD Cancer Center, University of California, San Diego, La Jolla, Calif, USA
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43
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Wang S, Ding YB, Chen GY, Xia JG, Wu ZY. Hypermethylation of Syk gene in promoter region associated with oncogenesis and metastasis of gastric carcinoma. World J Gastroenterol 2004; 10:1815-8. [PMID: 15188513 PMCID: PMC4572276 DOI: 10.3748/wjg.v10.i12.1815] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
AIM: To investigate the rrelationship between methylation of Syk (spleen tyrosine kinase) gene in promoter region and oncogenesis, metastasis of gastric carcinoma. The relation between silencing of the Syk gene and methylation of Syk promoter region was also studied.
METHODS: By using methylation-specific PCR (MSP) technique, the methylation of Syk promoter region in specimens from 61 gastric cancer patients (tumor tissues and adjacent normal tissues) was detected. Meanwhile, RT-PCR was used to analyse syk expression exclusively.
RESULTS: The expression of the Syk gene was detected in all normal gastric tissues. Syk expression in gastric carcinoma was lower in 14 out of 61 gastric cancer samples than in adjacent normal tissues (χ2 = 72.3, P < 0.05). No methylation of Syk promoter was found in adjacent normal tissues. hypermethylation of Syk gene in promoter was detected 21 cases in 61 gastric carcinoma patients. The rate of methylation of Syk promoter in gastric carcinoma was higher than that in adjacent normal tissues (χ2 = 25.1, P < 0.05). In 31 patients with lymph node metastasis, 17 were found with Syk promoter methylation. A significant difference was noted between two groups (χ2 = 11.4,P < 0.05).
CONCLUSION: Hypermethylation leads to silencing of the Syk gene in human gastric carcinoma. Methylation of Syk promoter is correlated to oncogenesis and metastasis of gastric carcinoma. Syk is considered to be a potential tumor suppressor and anti-metastasis gene in human gastric cancer.
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Affiliation(s)
- Shui Wang
- Department of General Surgery, First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, Jiangsu Province, China
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44
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Kanie T, Abe A, Matsuda T, Kuno Y, Towatari M, Yamamoto T, Saito H, Emi N, Naoe T. TEL-Syk fusion constitutively activates PI3-K/Akt, MAPK and JAK2-independent STAT5 signal pathways. Leukemia 2004; 18:548-55. [PMID: 14749700 DOI: 10.1038/sj.leu.2403266] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2003] [Accepted: 12/01/2003] [Indexed: 11/09/2022]
Abstract
We previously reported the fusion of the TEL gene to the Syk gene in myelodysplastic syndrome with t(9;12)(q22;p12). TEL-Syk fusion transformed interleukin-3 (IL-3)-dependent murine hematopoietic cell line BaF3 to growth factor independence. Here, we investigate the intracellular signal transduction of the stable transfectants. TEL-Syk fusion protein was associated with the p85 subunit of phosphatidyl inositol 3 kinase (PI3-K) followed by the activation of Akt in the absence of IL-3. Vav, phospholipase C-gamma2 and mitogen-activated protein kinase (MAPK) were also constitutively activated. TEL-Syk also activated the signal transducer and activator of transcription 5 (STAT5) in the absence of Janus kinase 2 activation. None of these kinases were phosphorylated in the BaF3 cells transfected with TELDeltaPNT-Syk in which the oligomerization domain of TEL was deleted. Inhibitor analysis showed that the MAPK pathway was important in TEL-Syk-mediated cell proliferation. The immunofluorescence technique revealed that the TEL-Syk fusion protein was located in the cytoplasm. These data suggest that TEL-Syk fusion protein in the cytoplasm leads to the constitutive activation of PI3-K/Akt, MAPK and STAT5 signal pathways, which are closely involved in IL-3-independent cell proliferation of BaF3 cells.
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Affiliation(s)
- T Kanie
- Department of Hematology, Graduate School of Medicine, Nagoya University, Nagoya, Japan
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45
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Hayashi K, Yamamoto M, Nojima T, Goitsuka R, Kitamura D. Distinct signaling requirements for Dmu selection, IgH allelic exclusion, pre-B cell transition, and tumor suppression in B cell progenitors. Immunity 2003; 18:825-36. [PMID: 12818163 DOI: 10.1016/s1074-7613(03)00142-0] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
The pre-B cell receptor triggers expansion and differentiation of pre-B cells (the pre-B cell transition), as well as inhibition of V(H) to DJ(H) recombination (allelic exclusion). The latter also accounts for counter-selection of pro-B cells expressing Dmu protein (Dmu selection). However, the signaling pathways responsible for these events remain poorly defined. Here we show complete arrest of B cell development at the pre-B cell transition in BASH/CD19 double mutant mice, indicating partial redundancy of the two B cell-specific adaptors. Allelic exclusion remained intact in the double mutant mice, whereas Dmu selection was abolished in BASH mutant mice. Thus, distinct signals are required for these events. In addition, both mutant mice succumbed to pre-B cell leukemia, indicating that BASH and CD19 contribute to tumor suppression.
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Affiliation(s)
- Katsuhiko Hayashi
- Division of Molecular Biology, Research Institute for Biological Sciences, Tokyo University of Science, Yamazaki 2669, Noda, 278-0022, Chiba, Japan
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46
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Jumaa H, Bossaller L, Portugal K, Storch B, Lotz M, Flemming A, Schrappe M, Postila V, Riikonen P, Pelkonen J, Niemeyer CM, Reth M. Deficiency of the adaptor SLP-65 in pre-B-cell acute lymphoblastic leukaemia. Nature 2003; 423:452-6. [PMID: 12761551 DOI: 10.1038/nature01608] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2003] [Accepted: 03/28/2003] [Indexed: 12/16/2022]
Abstract
Acute lymphoblastic leukaemia (ALL) is the commonest form of childhood malignancy, and most cases arise from B-cell clones arrested at the pre-B-cell stage of differentiation. The molecular events that arrest pre-B-cell differentiation in the leukaemic pre-B cells have not been well characterized. Here we show that the differentiation regulator SLP-65 (an adaptor protein also called BLNK or BASH) inhibits pre-B-cell leukaemia in mice. Reconstitution of SLP-65 expression in a SLP-65-/- pre-B-cell line led to enhanced differentiation in vitro and prevented the development of pre-B-cell leukaemia in immune-deficient mice. Tyrosine 96 of SLP-65 was required for this activity. The murine SLP-65-/- pre-B-cell leukaemia resembles human childhood pre-B ALL. Indeed, 16 of the 34 childhood pre-B ALL samples that were tested showed a complete loss or drastic reduction of SLP-65 expression. This loss is probably due to the incorporation of alternative exons into SLP-65 transcripts, leading to premature stop codons. Thus, the somatic loss of SLP-65 and the accompanying block in pre-B-cell differentiation might be one of the primary causes of childhood pre-B ALL.
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Affiliation(s)
- Hassan Jumaa
- Biologie III, University of Freiburg and Max Planck Institute for Immunobiology, D-79108 Freiburg, Germany.
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47
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Balaian L, Zhong RK, Ball ED. The inhibitory effect of anti-CD33 monoclonal antibodies on AML cell growth correlates with Syk and/or ZAP-70 expression. Exp Hematol 2003; 31:363-71. [PMID: 12763134 DOI: 10.1016/s0301-472x(03)00044-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
OBJECTIVES Acute myeloid leukemia (AML) cells express the cell surface antigen CD33 that can function as a downregulator of cell growth, mediating growth arrest and apoptosis. The protein kinase Syk is an essential element in several cascades coupling certain antigen receptors to cell responses. Recently we reported that CD33 recruits Syk for its signaling in AML cell lines. In this study, we further investigated the mechanism(s) of Syk engagement in CD33 signaling in primary AML samples. METHODS We investigated 25 primary AML samples for their proliferative response (3H-thymidine incorporation) and biochemical changes (Western blot analysis) to anti-CD33 mAb treatment. RESULTS Proliferation studies demonstrated that 14 (56%) of AML samples were responsive (R) while 11 (44%) were nonresponsive (n-R) to inhibitory antibody activity. Seven of 25 AML samples (28%) expressed undetectable levels of Syk. However, cells from two of these patients expressed the ZAP-70 protein kinase. In Syk/ZAP-70(+) samples, CD33 ligation inhibited proliferation in 70% of cases, while none of the Syk/ZAP-70(-) samples was responsive. There were significant biochemical differences between responder and nonresponder AML populations. In responder samples, CD33 ligation induced phosphorylation of CD33 andSyk and formation of the CD33/Syk complex. In nonresponder samples, CD33 was not phosphorylated, and Syk was in complex with the SHP-1 protein phosphatase constitutively. CONCLUSIONS Syk is an important component in the regulation of proliferation in AML cells. The differential response of AML cells to CD33 ligation is associated with the level of the Syk expression.
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Affiliation(s)
- Larisa Balaian
- Department of Medicine and Cancer Center, University of California, San Diego School of Medicine, La Jolla, Calif., USA
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48
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Goodman PA, Burkhardt N, Juran B, Tibbles HE, Uckun FM. Hypermethylation of the spleen tyrosine kinase promoter in T-lineage acute lymphoblastic leukemia. Oncogene 2003; 22:2504-14. [PMID: 12717427 DOI: 10.1038/sj.onc.1206313] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Sequence analysis of the noncoding first exon (exon 1) of the Syk gene demonstrated the presence of a previously cloned CpG island (GenBank #Z 65706). Transient transfection analysis in Daudi cells demonstrated promoter activity (18-fold increase over parental luciferase plasmid) for a 348 bp BstXI-BsrBI fragment containing this island. This region exhibits a high GC content (approximately 75%), contains several SP1 binding sites and a potential initiator sequence, but lacks a strong TATA consensus. Bisulfite sequencing and methylation-specific PCR (MSP) of this region demonstrated that the Syk promoter CpG island was largely unmethylated in B-lineage leukemia cell lines, control peripheral blood cells, human thymocytes and CD3(+) T lymphocytes. However, dense methylation was seen in four T-lineage leukemia cell lines, Jurkat, H9, Molt 3 and HUT 78. MSP screening of leukemia cells from six T-lineage acute lymphoblastic leukemia (ALL) patients demonstrated methylation of the Syk promoter CpG island in one T-lineage ALL patient. Promoter methylation was correlated with reduced to absent expression of Syk mRNA and SYK protein in the T-lineage leukemia cell lines. Treatment of the leukemia lines Ha and Molt 3, with the methylation inhibitor, 5-aza-2'-deoxycytidine (5-aza-CdR) resulted in increased Syk mRNA expression. The presence of a methylated promoter sequence in these T-lineage leukemia cell lines and in one T-lineage patient suggests a potential role for SYK as a tumor suppressor in T-ALL.
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Affiliation(s)
- Patricia A Goodman
- Department of Molecular Genetics, Parker Hughes Institute and Parker Hughes Cancer Center, 2699 Patton Road, St Paul, MN 55113, USA
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Janz S, Potter M, Rabkin CS. Lymphoma- and leukemia-associated chromosomal translocations in healthy individuals. Genes Chromosomes Cancer 2003; 36:211-23. [PMID: 12557221 DOI: 10.1002/gcc.10178] [Citation(s) in RCA: 121] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Chromosomal translocations (CTs) are hallmark mutations of hematopoietic malignancy that result in the deregulated expression of oncogenes or the generation of novel fusion genes. The polymerase chain reaction (PCR) can be used to detect illegitimate recombinations of genomic DNA sequences as a more sensitive assay than cytogenetics for determining the presence of CTs. Both direct DNA-PCR and reverse transcriptase-PCR were used to examine healthy individuals for lymphoma- and leukemia-associated CTs. Two oncogene-activating CTs [t(14;18)(q32;q21) and t(8;14)(q24;q32)] and one fusion-gene CT [t(2;5)(p23;q35)] from lymphomas and five fusion-gene CTs from leukemia [t(9;22)(q34;q11), t(4;11)(q21;q23), t(15;17)(q22;q11), t(12;21)(p13;q22), t(8;21)(q22;q22)] were detected in such studies. The biological implication is that CTs associated with malignant tumors may also be found in cells that are not neoplastic. CTs are characteristic attributes of neoplastic clones but are by themselves insufficient to cause malignant transformation. A better understanding of the special biology of non-neoplastic CT-bearing cells will provide insight into their putative role as tumor precursors. Prospective epidemiological studies are needed to determine whether such cells in healthy individuals may, in some instances, become clonogenic founders of lymphoma or leukemia.
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Affiliation(s)
- Siegfried Janz
- Laboratory of Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892-4256, USA.
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Goodman PA, Jurana B, Wood CM, Uckun F. Genomic studies of the spleen protein tyrosine kinase locus reveal a complex promoter structure and several genetic variants. Leuk Lymphoma 2002; 43:1627-35. [PMID: 12400606 DOI: 10.1080/1042819021000002965] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Here we show that the gene of the cytoplasmic tyrosine kinase SYK spans a region of 90kb with 13 coding exons, an alternative exon 14 and at least two 5' untranslated regions exons 1a and 1b. 5' RACE (Rapid amplification of cDNA ends) of human Syk cDNAs demonstrated a complex promoter usage and splicing pattern. We identified three common single nucleotide polymorphisms in the exon la promoter region of the Syk gene as well as a variant Syk cDNA haplotype. This haplotype was characterized by a constellation of 5 silent mutations in the Syk cDNA: 1065(C-T), 1302(G-C), 1338(G-A), 1521(C-T) and 1545(T-C). A hypervariable CATATA(n) repeat polymorphism was also localized to the intron between exons 11 and 12. These novel insights into the genomic organization, promoter structure and genetic variability of Syk will serve as a foundation for detailed molecular epidemiological investigation of its potential role in human cancer biology.
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Affiliation(s)
- Patricia A Goodman
- Department of Molecular Genetics, Parker Hughes Institute and Parker Hughes Cancer Center St Paul, MN 55113, USA
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