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Singh SK, Wang Y, Habib A, Priyadarshini M, Kodavali CV, Chen A, Ma W, Wang J, Hameed NUF, Hu B, Fuller GN, Kulich SM, Amankulor N, Colen RR, Edwards LA, Zinn PO. TP53-PTEN-NF1 depletion in human brain organoids produces a glioma phenotype in vitro. Front Oncol 2023; 13:1279806. [PMID: 37881491 PMCID: PMC10597663 DOI: 10.3389/fonc.2023.1279806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 09/25/2023] [Indexed: 10/27/2023] Open
Abstract
Glioblastoma (GBM) is fatal and the study of therapeutic resistance, disease progression, and drug discovery in GBM or glioma stem cells is often hindered by limited resources. This limitation slows down progress in both drug discovery and patient survival. Here we present a genetically engineered human cerebral organoid model with a cancer-like phenotype that could provide a basis for GBM-like models. Specifically, we engineered a doxycycline-inducible vector encoding shRNAs enabling depletion of the TP53, PTEN, and NF1 tumor suppressors in human cerebral organoids. Designated as inducible short hairpin-TP53-PTEN-NF1 (ish-TPN), doxycycline treatment resulted in human cancer-like cerebral organoids that effaced the entire organoid cytoarchitecture, while uninduced ish-TPN cerebral organoids recapitulated the normal cytoarchitecture of the brain. Transcriptomic analysis revealed a proneural GBM subtype. This proof-of-concept study offers a valuable resource for directly investigating the emergence and progression of gliomas within the context of specific genetic alterations in normal cerebral organoids.
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Affiliation(s)
- Sanjay K. Singh
- Department of Neurosurgery, MD Anderson Cancer Center, Houston, TX, United States
| | - Yan Wang
- Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Ahmed Habib
- Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Mamindla Priyadarshini
- Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Chowdari V. Kodavali
- Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Apeng Chen
- Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Wencai Ma
- Department of Radiology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Jing Wang
- Department of Bioinformatics, MD Anderson Cancer Center, Houston, TX, United States
| | - N. U. Farrukh Hameed
- Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Baoli Hu
- Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Gregory N. Fuller
- Department of Pathology, MD Anderson Cancer Center, Houston, TX, United States
| | - Scott M. Kulich
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Nduka Amankulor
- Department of Neurosurgery, Hospital of the University of Pennsylvania, Philadelphia, PA, United States
| | - Rivka R. Colen
- Department of Pathology, MD Anderson Cancer Center, Houston, TX, United States
| | - Lincoln A. Edwards
- Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
| | - Pascal O. Zinn
- Department of Neurosurgery, University of Pittsburgh Medical Center, Pittsburgh, PA, United States
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2
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Hanna GK, Madany M, Tay ASMS, Edwards LA, Kim S, Michael JS, Nuno M, Thomas T, Li A, Berel D, Black KL, Fan X, Zhang W, Rudnick JD, Wang R, Yu JS. ZEB1 loss increases glioma stem cell tumorigenicity and resistance to chemoradiation. J Neurosurg 2022; 138:1313-1324. [PMID: 36115050 DOI: 10.3171/2022.7.jns22259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 07/15/2022] [Indexed: 11/06/2022]
Abstract
OBJECTIVE Glioblastoma has been known to be resistant to chemotherapy and radiation, whereas the underlying mechanisms of resistance have not been fully elucidated. The authors studied the role of the transcription factor ZEB1 (zinc finger E-box-binding homeobox 1 protein), which is associated with epithelial-mesenchymal transition (EMT) and is central to the stemness of glioblastoma, to determine its role in therapeutic resistance to radiation and chemotherapy. The authors previously demonstrated that ZEB1 is deleted in a majority of glioblastomas. METHODS The authors explored resistance to therapy in the context of ZEB1 loss and overexpression in glioma stem cells (GSCs) and in patient data. RESULTS Patients with ZEB1 loss had a shorter survival time than patients with wild-type ZEB1 in both the high- and low-MGMT groups. Consistent with the clinical data, mice implanted with ZEB1 knockdown GSCs showed shortened survival compared with mice inoculated with nonsilencing control (NS) short-hairpin RNA (shRNA) GSC glioblastoma. ZEB1-deleted GSCs demonstrated increased tumorigenicity with regard to proliferation and invasion. Importantly, GSCs that lose ZEB1 expression develop enhanced resistance to chemotherapy, radiotherapy, and combined chemoradiation. ZEB1 loss may lead to increased HER3 expression through the HER3/Akt pathway associated with this chemoresistance. Conversely, overexpression of ZEB1 in GSCs that are ZEB1 null leads to increased sensitivity to chemoradiation. CONCLUSIONS The study results indicate that ZEB1 loss in cancer stem cells confers resistance to chemoradiation and uncovers a potentially targetable cell surface receptor in these resistant cells.
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Affiliation(s)
| | | | | | | | | | | | - Miriam Nuno
- Departments of1Neurosurgery and.,3Department of Biostatics, University of California, Davis, Sacramento, California
| | | | - Aiguo Li
- 4Neuro-Oncology Branch, National Institutes of Health/National Cancer Institute, Bethesda, Maryland; and
| | | | | | - Xuemo Fan
- 5Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles
| | - Wei Zhang
- 4Neuro-Oncology Branch, National Institutes of Health/National Cancer Institute, Bethesda, Maryland; and
| | - Jeremy D Rudnick
- Departments of1Neurosurgery and.,6Department of Medicine, Samuel Oschin Comprehensive Cancer Institute, Cedars-Sinai Medical Center, Los Angeles
| | - Rongfu Wang
- 7USC Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, California
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3
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Tay ASMS, Amano T, Edwards LA, Yu JS. CD133 mRNA-transfected dendritic cells induce coordinated cytotoxic and helper T cell responses against breast cancer stem cells. Mol Ther Oncolytics 2021; 22:64-71. [PMID: 34485687 PMCID: PMC8403713 DOI: 10.1016/j.omto.2021.05.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 05/12/2021] [Indexed: 01/16/2023]
Abstract
Breast cancer, a leading cause of death yearly, has been shown to be initiated and propagated by cancer stem cells. CD133, a cell surface antigen, has been shown to be present on cancer stem cells of many solid tumors, including breast cancer. A limitation to targeting CD133 is major histocompatibility complex (MHC)-restricted presentation of epitopes, leading to activation of only one arm of the immune system: either CD4+ helper T cells or CD8+ cytotoxic T cells. Thus, we hypothesized that by creating an MHC-independent vaccination, we would give rise to a sustained immune response against CD133 in triple-negative breast cancer (TNBCs). We transfected CD133 mRNA into dendritic cells and then tested this in animal models of TNBC. We showed in these models the activation of both CD8+ cytotoxic T cells and CD4+ helper T cells by dendritic cell vaccination with modified CD133 mRNA, with subsequent decrease in tumor growth. This study for the first time demonstrates in a syngeneic mouse model of TNBC that targeting CD133, in an MHC-independent manner, is an effective strategy against the cancer stem cell population, leading to tumor abrogation.
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Affiliation(s)
| | - Takayuki Amano
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Lincoln A Edwards
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - John S Yu
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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4
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Thomas TM, Miyaguchi K, Edwards LA, Wang H, Wollebo H, Aiguo L, Murali R, Wang Y, Braas D, Michael JS, Andres AM, Zhang M, Khalili K, Gottlieb RA, Perez JM, Yu JS. Elevated Asparagine Biosynthesis Drives Brain Tumor Stem Cell Metabolic Plasticity and Resistance to Oxidative Stress. Mol Cancer Res 2021; 19:1375-1388. [PMID: 33863814 DOI: 10.1158/1541-7786.mcr-20-0086] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2020] [Revised: 02/26/2021] [Accepted: 04/14/2021] [Indexed: 12/12/2022]
Abstract
Asparagine synthetase (ASNS) is a gene on the long arm of chromosome 7 that is copy-number amplified in the majority of glioblastomas. ASNS copy-number amplification is associated with a significantly decreased survival. Using patient-derived glioma stem cells (GSC), we showed that significant metabolic alterations occur in gliomas when perturbing the expression of ASNS, which is not merely restricted to amino acid homeostasis. ASNS-high GSCs maintained a slower basal metabolic profile yet readily shifted to a greatly increased capacity for glycolysis and oxidative phosphorylation when needed. This led ASNS-high cells to a greater ability to proliferate and spread into brain tissue. Finally, we demonstrate that these changes confer resistance to cellular stress, notably oxidative stress, through adaptive redox homeostasis that led to radiotherapy resistance. Furthermore, ASNS overexpression led to modifications of the one-carbon metabolism to promote a more antioxidant tumor environment revealing a metabolic vulnerability that may be therapeutically exploited. IMPLICATIONS: This study reveals a new role for ASNS in metabolic control and redox homeostasis in glioma stem cells and proposes a new treatment strategy that attempts to exploit one vulnerable metabolic node within the larger multilayered tumor network.
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Affiliation(s)
- Tom M Thomas
- Department of Neurosurgery, Maxine-Dunitz Neurosurgical Institute, Cedars Sinai Medical Center, Los Angeles, California
| | - Ken Miyaguchi
- Department of Neurosurgery, Maxine-Dunitz Neurosurgical Institute, Cedars Sinai Medical Center, Los Angeles, California
| | - Lincoln A Edwards
- Department of Neurosurgery, Maxine-Dunitz Neurosurgical Institute, Cedars Sinai Medical Center, Los Angeles, California
| | - Hongqiang Wang
- Department of Neurosurgery, Maxine-Dunitz Neurosurgical Institute, Cedars Sinai Medical Center, Los Angeles, California
| | - Hassen Wollebo
- Department of Neuroscience, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
| | - Li Aiguo
- Neuro-Oncology Branch, National Cancer Institute, Bethesda, Maryland
| | - Ramachandran Murali
- Department of Biomedical Sciences, Cedars Sinai Medical Center, Los Angeles, California
| | - Yizhou Wang
- Genomics Core, Cedars Sinai Medical Center, Los Angeles, California
| | - Daniel Braas
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, UCLA, Los Angeles, California
| | - Justin S Michael
- Department of Neurosurgery, Maxine-Dunitz Neurosurgical Institute, Cedars Sinai Medical Center, Los Angeles, California
| | - Allen M Andres
- Mitochondria and Metabolism Core, Cedars Sinai Medical Center, Los Angeles, California
| | - Miqin Zhang
- Department of Materials Science and Engineering, University of Washington, Seattle, Washington
| | - Kamel Khalili
- Department of Neuroscience, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
| | - Roberta A Gottlieb
- Mitochondria and Metabolism Core, Cedars Sinai Medical Center, Los Angeles, California
| | - J Manuel Perez
- Department of Neurosurgery, and Biomedical Imaging Research Institute, Cedars-Sinai Medical Center, Los Angeles, California
| | - John S Yu
- Department of Neurosurgery, Maxine-Dunitz Neurosurgical Institute, Cedars Sinai Medical Center, Los Angeles, California.
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5
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Do ASMS, Amano T, Edwards LA, Zhang L, De Peralta-Venturina M, Yu JS. CD133 mRNA-Loaded Dendritic Cell Vaccination Abrogates Glioma Stem Cell Propagation in Humanized Glioblastoma Mouse Model. Mol Ther Oncolytics 2020; 18:295-303. [PMID: 32728617 PMCID: PMC7378271 DOI: 10.1016/j.omto.2020.06.019] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Accepted: 06/19/2020] [Indexed: 01/24/2023]
Abstract
Cancer stem cells are initiating cells of cancer and propagate its growth through self-renewal and differentiation of its daughter cells. CD133 is a cell surface antigen that is present on glioma stem cells and has been used to prospectively isolate glioma stem cells. We hypothesized that a major histocompatibility complex (MHC)-independent and long-lasting immune response against CD133 could be generated by transfecting CD133 mRNA into dendritic cells and vaccinating animals with experimental gliomas. To test this hypothesis, we developed a novel humanized mouse model using CD34-positive hematopoietic stem cells. We confirmed the robust simultaneous activation of CD8- and CD4-positive T cells by dendritic cell vaccination with modified CD133 mRNA leading to a potent and long-lived immune response, with subsequent abrogation of CD133-positive glioma stem cell propagation and tumor growth. This study for the first time demonstrates in both a humanized mouse model and in a syngeneic mouse model of glioblastoma that targeting a glioma stem cell-associated antigen is an effective strategy to target and kill glioma stem cells. This novel and simple humanized mouse model for immunotherapy is a significant advance in our ability to test human-specific immunotherapies for glioblastoma.
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Affiliation(s)
| | - Takayuki Amano
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Lincoln A Edwards
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Lei Zhang
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | | | - John S Yu
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
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6
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Cacciottolo TM, Perikari A, van der Klaauw A, Henning E, Stadler LKJ, Keogh J, Farooqi IS, Tenin G, Keavney B, Ryan E, Budd R, Bewley M, Coelho P, Rumsey W, Sanchez Y, McCafferty J, Dockrell D, Walmsley S, Whyte M, Liu Y, Choy MK, Tenin G, Abraham S, Black G, Keavney B, Ford T, Stanley B, Good R, Rocchiccioli P, McEntegart M, Watkins S, Eteiba H, Shaukat A, Lindsay M, Robertson K, Hood S, McGeoch R, McDade R, Sidik N, McCartney P, Corcoran D, Collison D, Rush C, McConnachie A, Touyz R, Oldroyd K, Berry C, Gazdagh G, Diver L, Marshall J, McGowan R, Ahmed F, Tobias E, Curtis E, Parsons C, Maslin K, D'Angelo S, Moon R, Crozier S, Gossiel F, Bishop N, Kennedy S, Papageorghiou A, Fraser R, Gandhi S, Prentice A, Inskip H, Godfrey K, Schoenmakers I, Javaid MK, Eastell R, Cooper C, Harvey N, Watt ER, Howden A, Mirchandani A, Coelho P, Hukelmann JL, Sadiku P, Plant TM, Cantrell DA, Whyte MKB, Walmsley SR, Mordi I, Forteath C, Wong A, Mohan M, Palmer C, Doney A, Rena G, Lang C, Gray EH, Azarian S, Riva A, Edwards H, McPhail MJW, Williams R, Chokshi S, Patel VC, Edwards LA, Page D, Miossec M, Williams S, Monaghan R, Fotiou E, Santibanez-Koref M, Keavney B, Badat M, Mettananda S, Hua P, Schwessinger R, Hughes J, Higgs D, Davies J. Scientific Business Abstracts of the 113th Annual Meeting of the Association of Physicians of Great Britain and Ireland. QJM 2019; 112:724-729. [PMID: 31505685 DOI: 10.1093/qjmed/hcz175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
| | - A Perikari
- University of Cambridge Metabolic Research Laboratories
| | | | - E Henning
- University of Cambridge Metabolic Research Laboratories
| | - L K J Stadler
- University of Cambridge Metabolic Research Laboratories
| | - J Keogh
- University of Cambridge Metabolic Research Laboratories
| | - I S Farooqi
- University of Cambridge Metabolic Research Laboratories
| | - G Tenin
- From University of Manchester
| | | | - E Ryan
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - R Budd
- Department of Infection Immunity and Cardiovascular Disease, The Florey Institute for Host-Pathogen Interactions, University of Sheffield
| | - M Bewley
- Department of Infection Immunity and Cardiovascular Disease, The Florey Institute for Host-Pathogen Interactions, University of Sheffield
| | - P Coelho
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - W Rumsey
- Stress and Repair Discovery Performance Unit, Respiratory Therapy Area
| | - Y Sanchez
- Stress and Repair Discovery Performance Unit, Respiratory Therapy Area
| | - J McCafferty
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - D Dockrell
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - S Walmsley
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - M Whyte
- Department of Respiratory Medicine, Centre for Inflammation Research, University of Edinburgh
| | - Y Liu
- From the University of Manchester
| | - M-K Choy
- From the University of Manchester
| | - G Tenin
- From the University of Manchester
| | | | - G Black
- From the University of Manchester
| | | | - T Ford
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | | | - R Good
- Golden Jubilee National Hospital
| | - P Rocchiccioli
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - M McEntegart
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | | | - H Eteiba
- Golden Jubilee National Hospital
| | | | | | | | - S Hood
- Golden Jubilee National Hospital
| | | | - R McDade
- Golden Jubilee National Hospital
| | - N Sidik
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - P McCartney
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - D Corcoran
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - D Collison
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - C Rush
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | | | - R Touyz
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
| | - K Oldroyd
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - Colin Berry
- BHF Centre of Excellence in Vascular Science and Medicine, University of Glasgow
- Golden Jubilee National Hospital
| | - G Gazdagh
- School of Medicine, Dentistry & Nursing, College of Medical, Veterinary and Life Sciences, University of Glasgow
| | - L Diver
- West of Scotland Regional Genetics Service, Laboratory Medicine Building, Queen Elizabeth University Hospital
| | - J Marshall
- Institute of Cancer Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow
| | - R McGowan
- West of Scotland Regional Genetics Service, Laboratory Medicine Building, Queen Elizabeth University Hospital
| | - F Ahmed
- Developmental Endocrinology Research Group, Royal Hospital for Children, University of Glasgow
| | - E Tobias
- Academic Unit of Medical Genetics and Clinical Pathology, Laboratory Medicine Building, Queen Elizabeth University Hospital, University of Glasgow
| | - E Curtis
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - C Parsons
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - K Maslin
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - S D'Angelo
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - R Moon
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - S Crozier
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - F Gossiel
- Academic Unit of Bone Metabolism, University of Sheffield
| | - N Bishop
- Academic Unit of Child Health, University of Sheffield
| | - S Kennedy
- Nuffield Department of Women's & Reproductive Health, John Radcliffe Hospital, University of Oxford
| | - A Papageorghiou
- Nuffield Department of Women's & Reproductive Health, John Radcliffe Hospital, University of Oxford
| | - R Fraser
- Department of Obstetrics and Gynaecology, Sheffield Hospitals NHS Trust, University of Sheffield
| | - S Gandhi
- Department of Obstetrics and Gynaecology, Sheffield Hospitals NHS Trust, University of Sheffield
| | | | - H Inskip
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - K Godfrey
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - I Schoenmakers
- Department of Medicine, Faculty of Medicine and Health Sciences, University of East Anglia
| | - M K Javaid
- NIHR Oxford Biomedical Research Centre, University of Oxford
| | - R Eastell
- Academic Unit of Bone Metabolism, University of Sheffield
| | - C Cooper
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | - N Harvey
- MRC Lifecourse Epidemiology Unit, University of Southampton
| | | | - A Howden
- School of Life Sciences, University of Dundee
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - E H Gray
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - S Azarian
- Institute of Hepatology, Foundation for Liver Research
| | - A Riva
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - H Edwards
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - M J W McPhail
- School of Immunology and Microbial Sciences, King's College London
- Institute of Liver Studies & Transplantation, King's College Hospital
| | - R Williams
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - S Chokshi
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - V C Patel
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
- Institute of Liver Studies & Transplantation, King's College Hospital
| | - L A Edwards
- Institute of Hepatology, Foundation for Liver Research
- School of Immunology and Microbial Sciences, King's College London
| | - D Page
- University of Manchester
- Manchester Metropolitan University
| | - M Miossec
- Manchester Metropolitan University
- University of Newcastle
| | | | | | | | | | | | - M Badat
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - S Mettananda
- Department of Paediatrics, Faculty of Medicine, University of Kelaniya
| | - P Hua
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - R Schwessinger
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - J Hughes
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - D Higgs
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
| | - J Davies
- MRC Molecular Haematology Unit, MRC Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital
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7
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Edwards LA, Kim S, Madany M, Nuno M, Thomas T, Li A, Berel D, Lee BS, Liu M, Black KL, Fan X, Zhang W, Yu JS. ZEB1 Is a Transcription Factor That Is Prognostic and Predictive in Diffuse Gliomas. Front Neurol 2019; 9:1199. [PMID: 30705664 PMCID: PMC6345215 DOI: 10.3389/fneur.2018.01199] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 12/31/2018] [Indexed: 01/06/2023] Open
Abstract
Objective: To address the unmet medical need to better prognosticate patients with diffuse gliomas and to predict responses to chemotherapy regimens. Methods: ZEB1 alterations were retrospectively identified from a cohort of 1,160 diffuse glioma patients. Epigenome-wide association scans (EWAS) were performed on available data. We determined the utility of ZEB1 as a prognostic indicator of patient survival in diffuse gliomas and assessed the value of ZEB1 to predict the efficacy of treating diffuse glioma patients with procarbazine, CCNU, and vincristine along with radiation at diagnosis. Decision curve analysis (DCA) was used to determine if ZEB1 added benefit to clinical decision-making over and above conventional methods. Results: Fifteen percent of diffuse glioma patients had a ZEB1 deletion. ZEB1 deletion was associated with poor overall survival (OS) with and without adjustment for age and tumor grade (adjusted HR: 4.25; 95% CI: 2.35 to 7.66; P < 0.001). Decision curve analysis confirmed that ZEB1 status with or without IDH1 was more beneficial to clinical decision making than conventional information such as age and tumor grade. We showed that ZEB1 regulates TERT expression, and patients with ZEB1 deletions likely subsume patients with mutant TERT expression in diffuse gliomas. ZEB1 influenced clinical decision making to initiate procarbazine, CCNU, and vincristine treatment. Conclusion: We demonstrate the prognostic value of ZEB1 in diffuse glioma patients. We further determine ZEB1 to be a vital and influential molecular marker in clinical decisions that exceed conventional methods regarding whether to treat or not treat patients with diffuse glioma.
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Affiliation(s)
- Lincoln A Edwards
- Neurosurgery Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Sungjin Kim
- Biostatistics and Bioinformatics Research Center, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Mecca Madany
- Neurosurgery Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Miriam Nuno
- Neurosurgery Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Tom Thomas
- Neurosurgery Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Aiguo Li
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
| | - Dror Berel
- Biostatistics and Bioinformatics Research Center, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Bong-Sup Lee
- Neurosurgery Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Minzhi Liu
- Neurosurgery Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Keith L Black
- Neurosurgery Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Xuemo Fan
- Pathology and Laboratory Medicine Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
| | - Wei Zhang
- Neuro-Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD, United States
| | - John S Yu
- Neurosurgery Department, Cedars-Sinai Medical Center, Los Angeles, CA, United States
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8
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Abstract
The Zinc Finger E-box binding homeobox (ZEB1/TCF8 or DeltaEF1) is at the forefront of transcription factors involved in controlling epithelial-to-mesenchymal transitions (EMT). Essentially, EMT allows for the reorganization of epithelial cells to become migratory cells with a mesenchymal phenotype. In addition to ZEB1 being involved in embryonic development, ZEB1 has also been linked to processes involving micro-RNAs, long non-coding RNAs and stem cells. In recent years there has been an accumulation of evidence with regard to ZEB1 in various cancers. Although increased ZEB1 expression has largely been associated with EMT, cancer invasion, and tumorigenicity, there have been some episodic reports that have gone against the traditional reporting of the role of ZEB1. Indicating that the function of ZEB1 and the mechanisms by which ZEB1 facilitates its activities is more complex than was once appreciated. This complexity is further exacerbated by the notion that ZEB1 can act not only as a transcriptional repressor but a transcriptional activator as well. This review seeks to shed light on the complexity of ZEB1 with respect to cancer.
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Affiliation(s)
- Mecca Madany
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, CA, USA
| | - Tom Thomas
- Department of Pathology, Brigham & Women's Hospital, Harvard Medical School Boston, MA, USA
| | - Lincoln A Edwards
- Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY, USA
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9
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Edwards LA, Li A, Berel D, Madany M, Kim NH, Liu M, Hymowitz M, Uy B, Jung R, Xu M, Black KL, Rentsendorj A, Fan X, Zhang W, Yu JS. ZEB1 regulates glioma stemness through LIF repression. Sci Rep 2017; 7:69. [PMID: 28246407 PMCID: PMC5427900 DOI: 10.1038/s41598-017-00106-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 02/06/2017] [Indexed: 01/04/2023] Open
Abstract
The identification of a stem cell regulatory gene which is aberrantly expressed in glioma and associated with patient survival would increase the understanding of the role of glioma cancer stem cells (GCSCs) in the virulence of gliomas. Interrogating the genomes of over 4000 brain cancers we identified ZEB1 deletion in ~15% (grade II and III) and 50% of glioblastomas. Meta-analysis of ZEB1 copy number status in 2,988 cases of glioma revealed disruptive ZEB1 deletions associated with decreased survival. We identified ZEB1 binding sites within the LIF (stemness factor) promoter region, and demonstrate LIF repression by ZEB1. ZEB1 knockdown in GCSCs caused LIF induction commensurate with GCSC self-renewal and inhibition of differentiation. IFN-γ treatment to GCSCs induced ZEB1 expression, attenuating LIF activities. These findings implicate ZEB1 as a stem cell regulator in glioma which when deleted leads to increased stemness, tumorigenicity and shortened patient survival.
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Affiliation(s)
- Lincoln A Edwards
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Aiguo Li
- Neuro-Oncology Branch, National Cancer Institute, Bethesda, MD, USA
| | - Dror Berel
- Biostatistics Core, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Mecca Madany
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Nam-Ho Kim
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Minzhi Liu
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Mitch Hymowitz
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Benjamin Uy
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Rachel Jung
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Minlin Xu
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Keith L Black
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Altan Rentsendorj
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Xuemo Fan
- Pathology and Laboratory Medicine, Cedars-Sinai Medical Center, Los Angeles, California, USA
| | - Wei Zhang
- Neuro-Oncology Branch, National Cancer Institute, Bethesda, MD, USA
| | - John S Yu
- Department of Neurosurgery, Cedars-Sinai Medical Center, Los Angeles, California, USA.
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10
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Edwards EA, Lumsden J, Rivas C, Steed L, Edwards LA, Thiyagarajan A, Sohanpal R, Caton H, Griffiths CJ, Munafò MR, Taylor S, Walton RT. Gamification for health promotion: systematic review of behaviour change techniques in smartphone apps. BMJ Open 2016; 6:e012447. [PMID: 27707829 PMCID: PMC5073629 DOI: 10.1136/bmjopen-2016-012447] [Citation(s) in RCA: 187] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
OBJECTIVE Smartphone games that aim to alter health behaviours are common, but there is uncertainty about how to achieve this. We systematically reviewed health apps containing gaming elements analysing their embedded behaviour change techniques. METHODS Two trained researchers independently coded apps for behaviour change techniques using a standard taxonomy. We explored associations with user ratings and price. DATA SOURCES We screened the National Health Service (NHS) Health Apps Library and all top-rated medical, health and wellness and health and fitness apps (defined by Apple and Google Play stores based on revenue and downloads). We included free and paid English language apps using 'gamification' (rewards, prizes, avatars, badges, leaderboards, competitions, levelling-up or health-related challenges). We excluded apps targeting health professionals. RESULTS 64 of 1680 (4%) health apps included gamification and met inclusion criteria; only 3 of these were in the NHS Library. Behaviour change categories used were: feedback and monitoring (n=60, 94% of apps), reward and threat (n=52, 81%), and goals and planning (n=52, 81%). Individual techniques were: self-monitoring of behaviour (n=55, 86%), non-specific reward (n=49, 82%), social support unspecified (n=48, 75%), non-specific incentive (n=49, 82%) and focus on past success (n=47, 73%). Median number of techniques per app was 14 (range: 5-22). Common combinations were: goal setting, self-monitoring, non-specific reward and non-specific incentive (n=35, 55%); goal setting, self-monitoring and focus on past success (n=33, 52%). There was no correlation between number of techniques and user ratings (p=0.07; rs=0.23) or price (p=0.45; rs=0.10). CONCLUSIONS Few health apps currently employ gamification and there is a wide variation in the use of behaviour change techniques, which may limit potential to improve health outcomes. We found no correlation between user rating (a possible proxy for health benefits) and game content or price. Further research is required to evaluate effective behaviour change techniques and to assess clinical outcomes. TRIAL REGISTRATION NUMBER CRD42015029841.
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Affiliation(s)
- E A Edwards
- Centre for Primary Care and Public Health, Bart's and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - J Lumsden
- School of Experimental Psychology, University of Bristol, Bristol, UK MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
| | - C Rivas
- Centre for Primary Care and Public Health, Bart's and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK Faculty of Health Sciences, University of Southampton, Southampton, UK
| | - L Steed
- Centre for Primary Care and Public Health, Bart's and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - L A Edwards
- Institute of Liver Studies, King's College Hospital, London, UK
| | - A Thiyagarajan
- Centre for Primary Care and Public Health, Bart's and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - R Sohanpal
- Centre for Primary Care and Public Health, Bart's and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - H Caton
- Department of Computing and Information Systems, Kingston University, London, UK
| | - C J Griffiths
- Centre for Primary Care and Public Health, Bart's and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - M R Munafò
- School of Experimental Psychology, University of Bristol, Bristol, UK MRC Integrative Epidemiology Unit at the University of Bristol, Bristol, UK
| | - S Taylor
- Centre for Primary Care and Public Health, Bart's and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
| | - R T Walton
- Centre for Primary Care and Public Health, Bart's and The London School of Medicine and Dentistry, Queen Mary University of London, London, UK
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11
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Nowocin AK, Brown K, Edwards LA, Meader L, Hill JI, Wong W. An Extraperitoneal Technique for Murine Heterotopic Cardiac Transplantation. Am J Transplant 2015; 15:2491-4. [PMID: 25997384 DOI: 10.1111/ajt.13307] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 02/23/2015] [Accepted: 03/05/2015] [Indexed: 01/25/2023]
Abstract
The mouse heterotopic cardiac transplantation model has been used extensively by investigators in the field of organ transplantation to study the rejection process, test new antirejection treatments, tolerance induction protocols or to understand basic immunological principles. Due to its extensive use, any small refinement of the technique would have a major impact on replacement, reduction and refinement (commonly known as the 3Rs). Here, we describe a novel approach to refine this model. The donor aorta and pulmonary artery are anastomosed peripherally to the femoral artery and vein of the recipient, respectively. The technical success rate is comparable to the conventional abdominal site, but it avoids a laparotomy and handling of the bowels making it less invasive method. As a result, recipients recover faster and require less postoperative analgesia. It is a major refinement under one of the 3Rs and would represent an advance in animal welfare in scientific research.
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Affiliation(s)
- A K Nowocin
- Medical Research Council (MRC) Centre for Transplantation, King's College London, London, UK
| | - K Brown
- Medical Research Council (MRC) Centre for Transplantation, King's College London, London, UK
| | - L A Edwards
- Medical Research Council (MRC) Centre for Transplantation, King's College London, London, UK
| | - L Meader
- Medical Research Council (MRC) Centre for Transplantation, King's College London, London, UK
| | - J I Hill
- Medical Research Council (MRC) Centre for Transplantation, King's College London, London, UK
| | - W Wong
- Medical Research Council (MRC) Centre for Transplantation, King's College London, London, UK
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12
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Edwards LA, Woolard K, Son MJ, Li A, Lee J, Ene C, Mantey SA, Maric D, Song H, Belova G, Jensen RT, Zhang W, Fine HA. Effect of brain- and tumor-derived connective tissue growth factor on glioma invasion. J Natl Cancer Inst 2011; 103:1162-78. [PMID: 21771732 DOI: 10.1093/jnci/djr224] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Tumor cell invasion is the principal cause of treatment failure and death among patients with malignant gliomas. Connective tissue growth factor (CTGF) has been previously implicated in cancer metastasis and invasion in various tumors. We explored the mechanism of CTGF-mediated glioma cell infiltration and examined potential therapeutic targets. METHODS Highly infiltrative patient-derived glioma tumor-initiating or tumor stem cells (TIC/TSCs) were harvested and used to explore a CTGF-induced signal transduction pathway via luciferase reporter assays, chromatin immunoprecipitation (ChIP), real-time polymerase chain reaction, and immunoblotting. Treatment of TIC/TSCs with small-molecule inhibitors targeting integrin β1 (ITGB1) and the tyrosine kinase receptor type A (TrkA), and short hairpin RNAs targeting CTGF directly were used to reduce the levels of key protein components of CTGF-induced cancer infiltration. TIC/TSC infiltration was examined in real-time cell migration and invasion assays in vitro and by immunohistochemistry and in situ hybridization in TIC/TSC orthotopic xenograft mouse models (n = 30; six mice per group). All statistical tests were two-sided. RESULTS Treatment of TIC/TSCs with CTGF resulted in CTGF binding to ITGB1-TrkA receptor complexes and nuclear factor kappa B (NF-κB) transcriptional activation as measured by luciferase reporter assays (mean relative luciferase activity, untreated vs CTGF(200 ng/mL): 0.53 vs 1.87, difference = 1.34, 95% confidence interval [CI] = 0.69 to 2, P < .001). NF-κB activation resulted in binding of ZEB-1 to the E-cadherin promoter as demonstrated by ChIP analysis with subsequent E-cadherin suppression (fold increase in ZEB-1 binding to the E-cadherin promoter region: untreated + ZEB-1 antibody vs CTGF(200 ng/mL) + ZEB-1 antibody: 1.5 vs 6.4, difference = 4.9, 95% CI = 4.8 to 5.0, P < .001). Immunohistochemistry and in situ hybridization revealed that TrkA is selectively expressed in the most infiltrative glioma cells in situ and that the surrounding reactive astrocytes secrete CTGF. CONCLUSION A CTGF-rich microenvironment facilitates CTGF-ITGB1-TrkA complex activation in TIC/TSCs, thereby increasing the invasiveness of malignant gliomas.
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Affiliation(s)
- Lincoln A Edwards
- Neuro-Oncology Branch, National Cancer Institute/National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892-1002, USA
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13
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Edwards LA, Lucas M, Edwards EA, Torrente F, Heuschkel RB, Klein NJ, Murch SH, Bajaj-Elliott M, Phillips AD. Aberrant response to commensal Bacteroides thetaiotaomicron in Crohn's disease: an ex vivo human organ culture study. Inflamm Bowel Dis 2011; 17:1201-8. [PMID: 21484962 DOI: 10.1002/ibd.21501] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2010] [Accepted: 08/23/2010] [Indexed: 12/15/2022]
Abstract
BACKGROUND Human ex vivo evidence indicating that an inappropriate immune response(s) to nonpathogenic bacteria contributes to disease pathogenesis in pediatric Crohn's disease (CD) is limited. The aim of the present study was to compare and contrast the early innate immune response of pediatric "healthy" versus CD mucosa to pathogenic, probiotic, and commensal bacteria. METHODS "Healthy control" and CD pediatric mucosal biopsies (terminal ileum and transverse colon) were cocultured for 8 hours with E. coli O42, Lactobacillus GG (LGG), Bacteroidesthetaiotaomicron (B. theta), or stimulated with interleukin (IL)-1β (positive control). Matched nonstimulated biopsies served as experimental controls. IL-8 was the immune marker of choice. IL-8 mRNA and protein levels were quantified by quantitative polymerase chain reaction and sandwich enzyme-linked immunosorbent assay, respectively. RESULTS IL-8 secretion was observed when control, ileal biopsies were exposed to pathogenic O42 and probiotic LGG, with no response noted to commensal B. theta. In comparison, Crohn's ileal biopsies showed impaired ability to induce IL-8 in response to O42 and LGG. Control colonic tissue showed a limited response to O42 or B. theta and LGG significantly reduced IL-8 secretion. Unlike control tissue, however, Crohn's ileal and colonic tissue did respond to B. theta, with more enhanced expression in the colon. CONCLUSIONS We provide the first ex vivo data to support the notion that aberrant mucosal recognition of commensal bacteria may contribute to pediatric CD. While IL-8 responses to O42 and LGG varied with disease status and anatomical location, B. theta consistently induced significant IL-8 both in ileal and colonic CD tissue, which was not seen in control, healthy tissue.
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Affiliation(s)
- L A Edwards
- Centre for Paediatric Gastroenterology, Lower Ground Floor, Royal Free Hospital, London, UK.
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14
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Abstract
In this issue of Cancer Cell, Anido et al. demonstrate that Id1 is the likely arbiter of divergent transforming growth factor-β (TGF-β) signaling in glioma-initiating cells (GICs) from different tumors. These findings hold both the promise and potential peril of therapeutic targeting of the TGF-β pathway.
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Affiliation(s)
- Lincoln A Edwards
- Neuro-Oncology Branch, National Cancer Institute, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892, USA
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15
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Edwards LA, Woo J, Huxham LA, Verreault M, Dragowska WH, Chiu G, Rajput A, Kyle AH, Kalra J, Yapp D, Yan H, Minchinton AI, Huntsman D, Daynard T, Waterhouse DN, Thiessen B, Dedhar S, Bally MB. Suppression of VEGF secretion and changes in glioblastoma multiforme microenvironment by inhibition of integrin-linked kinase (ILK). Mol Cancer Ther 2008; 7:59-70. [PMID: 18202010 DOI: 10.1158/1535-7163.mct-07-0329] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Integrin-linked kinase (ILK) was assesed as a therapeutic target in glioblastoma xenograft models through multiple endpoints including treatment related changes in the tumor microenvironment. Glioblastoma cell lines were tested in vitro for sensitivity toward the small-molecule inhibitors QLT0254 and QLT0267. Cell viability, cell cycle, and apoptosis were evaluated using MTT assay, flow cytometry, caspase activation, and DAPI staining. Western blotting and ELISA were used for protein analysis (ILK, PKB/Akt, VEGF, and HIF-1alpha). In vivo assessment of growth rate, cell proliferation, BrdUrd, blood vessel mass (CD31 labeling), vessel perfusion (Hoechst 33342), and hypoxia (EF-5) was done using U87MG glioblastoma xenografts in RAG2-M mice treated orally with QLT0267 (200 mg/kg q.d.). ILK inhibition in vitro with QLT0254 and QLT0267 resulted in decreased levels of phospho-PKB/Akt (Ser473), secreted VEGF, G2-M block, and apoptosis induction. Mice treated with QLT0267 exhibited significant delays in tumor growth (treated 213 mm3 versus control 549 mm3). In situ analysis of U87MG tumor cell proliferation from QLT0267-treated mice was significantly lower relative to untreated mice. Importantly, VEGF and HIF-1alpha expression decreased in QLT0267-treated tumors as did the percentage of blood vessel mass and numbers of Hoechst 33342 perfused tumor vessels compared with control tumors (35% versus 83%). ILK inhibition with novel small-molecule inhibitors leads to treatment-associated delays in tumor growth, decreased tumor angiogenesis, and functionality of tumor vasculature. The therapeutic effects of a selected ILK inhibitor (QLT0267) should be determined in the clinic in cancers that exhibit dysregulated ILK, such as PTEN-null glioblastomas.
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Affiliation(s)
- Lincoln A Edwards
- Department of Advanced Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
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16
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Rowland RE, Edwards LA, Podd JV. Elevated sister chromatid exchange frequencies in New Zealand Vietnam War veterans. Cytogenet Genome Res 2007; 116:248-51. [PMID: 17431321 DOI: 10.1159/000100407] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2006] [Accepted: 12/15/2006] [Indexed: 11/19/2022] Open
Abstract
From July 1965 until November 1971, New Zealand Defence Force Personnel fought in the Vietnam War. During this time more than 76,500,000 litres of phenoxylic herbicides were sprayed over parts of Southern Vietnam and Laos, the most common being known as 'Agent Orange'. The current study aimed to ascertain whether or not New Zealand Vietnam War veterans show evidence of genetic disturbance arising as a consequence of their now confirmed exposure to these defoliants. A sample group of 24 New Zealand Vietnam War veterans and 23 control volunteers were compared using an SCE (sister chromatid exchange) analysis. The results from the SCE study show a highly significant difference (P < 0.001) between the mean of the experimental group (11.05) and the mean of a matched control group (8.18). The experimental group also has an exceptionally high proportion of HFCs (cells with high SCE frequencies) above the 95th percentile compared to the controls (11.0 and 0.07%, respectively). We conclude that the New Zealand Vietnam War veterans studied here were exposed to a clastogenic substance(s) which continues to exert an observable genetic effect today, and suggest that this is attributable to their service in Vietnam.
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Affiliation(s)
- R E Rowland
- Institute of Molecular Biosciences, Massey University, Palmerston North, New Zealand.
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17
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Chiu GNC, Edwards LA, Kapanen AI, Malinen MM, Dragowska WH, Warburton C, Chikh GG, Fang KYY, Tan S, Sy J, Tucker C, Waterhouse DN, Klasa R, Bally MB. Modulation of cancer cell survival pathways using multivalent liposomal therapeutic antibody constructs. Mol Cancer Ther 2007; 6:844-55. [PMID: 17339368 DOI: 10.1158/1535-7163.mct-06-0159] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Various methods have been explored to enhance antibody-based cancer therapy. The use of multivalent antibodies or fragments against tumor antigens has generated a great deal of interest, as various cellular signals, including induction of apoptosis, inhibition of cell growth/survival, or internalization of the surface molecules, can be triggered or enhanced on extensive cross-linking of the target/antibody complex by the multivalent form of the antibody. The goal of the studies reported here was to develop multivalent antibody constructs via grafting of antibody molecules onto liposome membranes to enhance antibody activity. Using trastuzumab and rituximab as examples, up to a 25-fold increase in the antibody potency in cell viability assay was observed when the antibodies were presented in the multivalent liposome formulation. Key cell survival signaling molecules, such as phosphorylated Akt and phosphorylated p65 nuclear factor-kappaB, were down-regulated on treatment with multivalent liposomal trastuzumab and liposomal rituximab, respectively. Potent in vivo antitumor activity was shown for liposomal trastuzumab. The data presented here showed the potential of liposome technology to enhance the therapeutic effect of antibodies via a mechanism that modulates cell survival through clustering of the target/antibody complex.
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MESH Headings
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal, Humanized
- Antibodies, Monoclonal, Murine-Derived
- Antibodies, Neoplasm
- Antigens, CD20/immunology
- Antigens, Neoplasm/immunology
- Antineoplastic Agents/administration & dosage
- Blotting, Western
- Breast Neoplasms/immunology
- Breast Neoplasms/pathology
- Breast Neoplasms/therapy
- Cell Survival
- DNA-Binding Proteins/genetics
- DNA-Binding Proteins/physiology
- Down-Regulation
- Female
- Flow Cytometry
- Genes, erbB-2/genetics
- Genes, erbB-2/immunology
- Humans
- Liposomes
- Mice
- Mice, Knockout
- Phosphorylation
- Proto-Oncogene Proteins c-akt/metabolism
- Receptor, ErbB-2/immunology
- Rituximab
- Signal Transduction
- Transcription Factor RelA/metabolism
- Trastuzumab
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Affiliation(s)
- Gigi N C Chiu
- Department of Pharmacy, Faculty of Science, National University of Singapore, 18 Science Drive 4, Singapore 117543, Singapore.
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18
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Edwards LA, Verreault M, Thiessen B, Dragowska WH, Hu Y, Yeung JHF, Dedhar S, Bally MB. Combined inhibition of the phosphatidylinositol 3-kinase/Akt and Ras/mitogen-activated protein kinase pathways results in synergistic effects in glioblastoma cells. Mol Cancer Ther 2006; 5:645-54. [PMID: 16546979 DOI: 10.1158/1535-7163.mct-05-0099] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The present study uses cell-based screening assays to assess the anticancer effects of targeting phosphatidylinositol 3-kinase-regulated integrin-linked kinase (ILK) in combination with small-molecule inhibitors of Raf-1 or mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase kinase (MEK). The objective was to determine if synergistic interactions are achievable through the use of agents targeting two key cell signaling pathways involved in regulating glioblastoma cancer. The phosphatidylinositol 3-kinase/protein kinase B (PKB)/Akt and the Ras/MAPK pathway were targeted for their involvement in cell survival and cell proliferation, respectively. The glioblastoma cell lines U87MG, SF-188, and U251MG were transiently transfected with an antisense oligonucleotide targeting ILK (ILKAS) alone or in combination with the Raf-1 inhibitor GW5074 or with the MEK inhibitor U0126. Dose and combination effects were analyzed by the Chou and Talalay median-effect method and indicated that combinations targeting ILK with either Raf-1 or MEK resulted in a synergistic interaction. Glioblastoma cells transfected with ILKAS exhibited reduced levels of ILK and phosphorylated PKB/Akt on Ser473 but not PKB/Akt on Thr308 as shown by immunoblot analysis. These results were confirmed using glioblastoma cells transfected with ILK small interfering RNA, which also suggested enhanced gene silencing when used in combination with U0126. U87MG glioblastoma cells showed a 90% (P < 0.05) reduction in colony formation in soft agar with exposure to ILKAS in combination with GW5074 compared with control colonies. A substantial increase in Annexin V-positive cells as determined by using fluorescence-activated cell sorting methods were seen in combinations that included ILKAS. Combinations targeting ILK and components of the Ras/MAPK pathway result in synergy and could potentially be more effective against glioblastoma cancer than monotherapy.
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Affiliation(s)
- Lincoln A Edwards
- Department of Advanced Therapeutics, BC Cancer Agency, Vancouver, British Columbia, Canada
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19
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Edwards LA, Thiessen B, Dragowska WH, Daynard T, Bally MB, Dedhar S. Inhibition of ILK in PTEN-mutant human glioblastomas inhibits PKB/Akt activation, induces apoptosis, and delays tumor growth. Oncogene 2005; 24:3596-605. [PMID: 15782140 DOI: 10.1038/sj.onc.1208427] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The tumor suppressor gene phosphatase and tensin homologue (PTEN) regulates the phosphatidylinositol-3'-kinase (PI3K) signaling pathway and has been shown to correlate with poor prognosis in high-grade astrocytomas when mutational inactivation or loss of the PTEN gene occurs. PTEN mutation leads to constitutive activation of protein kinase B (PKB)/Akt with phosphorylation at the PKB/Akt sites Thr-308 and Ser-473. Integrin-linked kinase (ILK) has been shown to regulate PKB/Akt activity with the loss of PTEN in prostate cancer. We now demonstrate that ILK activity regulates PKB/Akt activity in glioblastoma cells. The activity of ILK is constitutively elevated in a serum-independent manner in PTEN mutant cells, and transfection of wild-type PTEN under the control of an inducible promoter into mutant PTEN cells inhibits ILK activity. Transfection of ILK antisense (ILKAS) or exposure to a small-molecule ILK inhibitor suppresses the constitutive phosphorylation of PKB/Akt on Ser-473 in PTEN-mutant glioblastoma cell lines. In addition, the delivery of ILKAS to PTEN-negative glioblastoma cells resulted in apoptosis. Rag-2M mice bearing established ( approximately 100 mg) human U87MG glioblastoma tumors, treated QD x 5 for 3 consecutive weeks with ILKAS (i.p. 5 mg/kg), exhibited stable disease with < or =7% increase in tumor volume over the 3-week course of treatment. In contrast, animals treated with an oligonucleotide control or saline exhibited a >100% increase in tumor volume over the same time period. Our initial results indicate that therapeutic strategies targeting ILK may be beneficial in the treatment of glioblastomas.
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Affiliation(s)
- Lincoln A Edwards
- Department of Advanced Therapeutics, BC Cancer Agency, Vancouver, BC, Canada.
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20
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Affiliation(s)
- Lincoln A Edwards
- Advanced Therapeutics, BC Cancer Agency and Research Centre, Department of Pathology & Laboratory Medicine, The University of British Columbia
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21
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Stoll B, Edwards LA. Critical Incident Stress Management with inmates: an atypical application. Int J Emerg Ment Health 2002; 3:245-7. [PMID: 12025484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/25/2023]
Abstract
In March 2001, Centerstone Community Mental Health Centers, Inc.'s CISM Team was asked to debrief 14 inmates after a murder in a rural county jail. We had no specific experience providing CISM in this particular setting, so we contacted ICISF and local law enforcement personnel for their input. We found that neither had a significant amount of experience with this population. In general, although our Team found significant differences related to the restrictions inherent in the environmental setting and the overall group dynamic, we also found similarities in the general manner in which the CISM model was utilized.
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Affiliation(s)
- B Stoll
- Centerstone Community Mental Health Centers, Inc., Nashville, TN, USA
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Edwards LA, Read LC, Nishio SJ, Weir AJ, Hull W, Barry S, Styne D, Whitsett JA, Tarantal AF, George-Nascimento C. Comparison of the distinct effects of epidermal growth factor and betamethasone on the morphogenesis of the gas exchange region and differentiation of alveolar type II cells in lungs of fetal rhesus monkeys. J Pharmacol Exp Ther 1995; 274:1025-32. [PMID: 7636717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
To compare the effects of epidermal growth factor (EGF) and betamethasone on the morphogenesis of the gas exchange region and the differentiation of the alveolar type II cell during fetal lung development, fetal rhesus monkeys (78% gestation) were treated in utero with EGF (5.33 mg/kg total dose), beta-methasone (2.6 mg/kg total dose) or the carrier, saline (control), every other day for 7 days. EGF-treated monkeys had significantly increased body and adrenal weights. Betamethasone-treated monkeys had significantly decreased body and adrenal weights. Exogenous EGF reduced cytoplasmic glycogen and increased the cytoplasmic organelle and SP-A content within alveolar type II cells. In contrast, exogenous betamethasone did not alter alveolar type II cell cytodifferentiation. Neither EGF nor betamethasone treatment significantly altered the structure of the gas exchange region as shown by a lack of change from controls in alveolar airspace size or in the fraction of the gas exchange region that was potential airspace. We conclude that at clinically relevant doses, EGF greatly accelerates the maturation of alveolar type II cells, whereas betamethasone does not. Exogenous EGF may act directly on alveolar type II cells because these cells contain EGF receptor. Neither EGF nor betamethasone had dramatic effects on the morphogenesis of the gas exchange region.
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Affiliation(s)
- L A Edwards
- Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California, USA
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Affiliation(s)
- L A Edwards
- Family Medicine Programme, North Adelaide, SA
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24
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Martinez-Bilbao M, Holdsworth RE, Edwards LA, Huber RE. A highly reactive beta-galactosidase (Escherichia coli) resulting from a substitution of an aspartic acid for Gly-794. J Biol Chem 1991; 266:4979-86. [PMID: 1900512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The beta-galactosidases of several mutagenized strains of Escherichia coli K12 which grew on lactobionate were found to be heat labile. Sequence analysis of the lacZ gene (ligated into Bluescript) of one of these strains (E. coli REH4) showed that the only change in the amino acid sequence was a substitution of an Asp for Gly-794. This change caused a dramatic increase of the activity when lactose was the substrate. The kcat of the purified enzyme from E. coli REH4 (G794D-beta-galactosidase) with lactose as the substrate was five to six times as large as the kcat of the normal enzyme with lactose. Purified G794D-beta-galactosidase was, however, less stable to heat and also to chymotrypsin (which cleaves next to Trp-585) than was normal beta-galactosidase. G794D-beta-Galactosidase bound substrates and substrate analog inhibitors less well than did normal beta-galactosidase while planar transition state analog inhibitors were more strongly bound. The ability to bind 2-amino-D-galactose (a positively charged transition state analog inhibitor) was either unaltered or was decreased somewhat. The data showed that the alteration in structure caused an increase in the value of k2 (the rate constant for the step in which the glycosidic bond is cleaved) with each substrate tested (the increase was at least 25-fold when lactose was the substrate) while k3 was decreased about 4-fold (k3 is the rate constant for the common hydrolysis step with each substrate). Since k2 is rate determining when lactose is the substrate of the normal enzyme, the increase in k2 resulted in a large increase in rate despite the fact that the value of k3 decreased. Large rate increases were not found with the other two substrates because the k2 values were not increased by large factors and because the decrease in the value of k3 negated the effects of the increased k2 values. The destabilization of the substrate binding coupled with a stabilization of the binding of a planar transition state is a possible cause of the significant increase in the value of k2 and of the enhanced activity with lactose.
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Affiliation(s)
- M Martinez-Bilbao
- Division of Biochemistry, Faculty of Science, University of Calgary, Alberta, Canada
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Abstract
Electrical field stimulation of dog isolated basilar artery produced neurogenically mediated contractions which were unaffected by phentolamine (1 microM), atropine (1 microM), ketanserin (1 microM) or methiothepin (0.1 microM). Responses were abolished by GR32191 (1-10 nM), BM 13.177 (0.1-10 microM) or flurbiprofen (0.5 microM) and markedly attenuated by dazoxiben (1-10 microM). Removal of the endothelium by Triton X-100-perfusion did not modify the magnitude of contractions to electrical stimulation and GR32191 still abolished the responses. GR32191 (1-10 nM) did not modify neurogenically mediated contraction of rabbit ear artery or potassium chloride-induced contraction of dog basilar artery. The results suggest that electrical field stimulation of dog basilar artery causes contractions which are mediated via a cyclo-oxygenase product with characteristics similar to thromboxane. This thromboxane-like substance is not endothelial in origin, nor released by contraction of the cerebrovascular smooth muscle per se and is therefore derived from a subendothelial, possibly neuronal, source.
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Affiliation(s)
- H E Connor
- Department of Cardiovascular Pharmacology, Glaxo Group Research Ltd., Ware, Hertfordshire, U.K
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Ellis JS, Jennings AC, Edwards LA, Mavandad M, Lamb CJ, Dixon RA. Defense gene expression in elicitor-treated cell suspension cultures of french bean cv. Imuna. Plant Cell Rep 1989; 8:504-507. [PMID: 24233540 DOI: 10.1007/bf00269060] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/1989] [Revised: 10/03/1989] [Indexed: 06/02/2023]
Abstract
Cell suspension cultures of bean (Phaseolus vulgaris) cv. Imuna accumulated isoflavonoid phytoalexins on exposure to elicitor from the phytopathogenic fungus Colletotrichum lindemuthianum (CL). This was preceeded by rapid increases in the activities of phenylalanine ammonia-lyase (PAL) and chalcone synthase (CHS). However, the patterns of expression of PAL and CHS genes differed from those observed in cultures of a previously studied bean cultivar. The relative levels of transcripts from individual members of the CHS multigene family differed significantly at 1.5 h compared to 22.5 h after elicitation. More strikingly, three PAL genes were expressed in cultivar Imuna in response to fungal elicitor, whereas two are expressed in elicitor-treated cell cultures of cultivar Canadian Wonder.
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Affiliation(s)
- J S Ellis
- Department of Biochemistry, Royal Holloway and Bedford New College, University of London, Egham Hill, TW20 OEX, Egham, Surrey, UK
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Huber RE, Edwards LA, Carne TJ. Studies on the mechanism of the iodination of tyrosine by lactoperoxidase. J Biol Chem 1989; 264:1381-6. [PMID: 2912960] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Studies with lactoperoxidase showed that a highly reactive intermediate is produced (on the enzyme) from I- and H2O2 which then diffuses from the enzyme and very rapidly and indiscriminately iodinates any Tyr or peptides containing Tyr which are in the same solution. The evidence supporting these conclusions follows. 1) The rate followed the Michaelis-Menten pattern with I- and H2O2 while the concentration of Tyr peptides had no measurable effect on the rate; 2) the rates of reaction were independent of the type of peptide in which Tyr was located; 3) the amount of iodination which had occurred after the reaction had gone to completion and the amounts of monoiodination and diiodination after completion of the reaction were independent of the peptide type, the pH, the solvent polarity, or the ionic strength; 4) competition for reaction by two very different Tyr peptides depended only on their initial concentrations; and 5) iodination of a large protein occurred through a dialysis membrane. Free Tyr was iodinated at the same rate as Tyr peptides by lactoperoxidase, but monoiodotyrosine and m-fluorotyrosine were iodinated at one-half that rate. The results also showed that one can choose ratios of [peptide] to [H2O2] such that monoiodination is maximized relative to diiodination. It was also found that the iodination capacity of a mixture of I- and H2O2 with lactoperoxidase (when Tyr was absent) was only slowly dissipated. Finally, the results showed that lactoperoxidase can be used to brominate and chlorinate Tyr peptides at a slow rate.
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Affiliation(s)
- R E Huber
- Division of Biochemistry, Faculty of Science, University of Calgary, Alberta, Canada
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Edwards LA, Tian MR, Huber RE, Fowler AV. The use of limited proteolysis to probe interdomain and active site regions of beta-galactosidase (Escherichia coli). J Biol Chem 1988; 263:1848-54. [PMID: 3123481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Limited proteolysis by pancreatic elastase (EC 3.4.21.36) and chymotrypsin (EC 3.4.21.1) was used to study the domain structure and active site of beta-galactosidase (EC 3.2.1.23) (Escherichia coli). Treatment with elastase resulted in a rapid cleavage between residues Ala-732 and Ala-733. No inactivation accompanied this cleavage suggesting that this bond is in a hinge region of the protein. Some slow cleavages beyond the initial one were observed to occur and were accompanied by inactivation. Treatment of beta-galactosidase with chymotrypsin resulted in cleavages first between Trp-585 and Ser-586 and then between Phe-601 and Cys-602. The first of these cleavages resulted in total inactivation of beta-galactosidase. The presence of monovalent ions or isopropyl-beta-D-thiogalactopyranoside protected against the cleavages but when Mg2+ or Mn2+ was present in the reaction mixture, the bond between Trp-585 and Ser-586 was more susceptible to the action of chymotrypsin. These data demonstrate that the conformation of beta-galactosidase around Trp-585 and Ser-586 is dramatically affected by the binding of ions and isopropyl-beta-D-thiogalactopyranoside. The mutant M15 beta-galactosidase, which is missing residues 11 through 41 and is an inactive dimer rather than an active tetramer, was found to be much more labile to proteases than native beta-galactosidase, but the same initial cleavages were found to occur. In addition, trypsin cleaved the M15 protein between Arg-431 and Trp-432 while native beta-galactosidase was stable to trypsin.
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Affiliation(s)
- L A Edwards
- Department of Biological Sciences, University of Calgary, Alberta, Canada
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Edwards LA, Tian MR, Huber RE, Fowler AV. The use of limited proteolysis to probe interdomain and active site regions of beta-galactosidase (Escherichia coli). J Biol Chem 1988. [DOI: 10.1016/s0021-9258(19)77954-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
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Abstract
Separation of tyrosine, fluorotyrosine, monoiodotyrosine and diiodotyrosine was achieved by reversed-phase high-performance liquid chromatography (HPLC) using a gradient of acetonitrile with water and using trifluoroacetic acid for ion pairing. No derivatization of the amino acids, prior to separation, was needed. The spectral properties of Tyr and its fluorine and iodine derivatives and the dependence of their absorbance maxima on pH, made it possible to analyze and differentiate between these derivatives in the free amino acid form or in peptides. This analysis was accomplished by adjusting the post column HPLC eluate from two identical runs to different pH values and then comparing the spectra of the peaks from these two runs with a diode array detector. Hydrolysis in 6 M hydrochloric acid was totally destructive to mono- and diiodotyrosine. However, base hydrolysis in 13.5 M sodium hydroxide for 30 min at 121 degrees C in an autoclave caused no destruction and allowed excellent recovery of all of the Tyr derivatives. This is the first report of simple methods for the detection and analysis of these amino acids and of a hydrolytic method which protects against their loss. A method of storage was also proposed.
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Edwards LA, Huber RE. A detailed examination of the iodination of beta-galactosidase: stoichiometric inactivation by nonspecific iodination. Biochem Cell Biol 1986; 64:523-7. [PMID: 3091051 DOI: 10.1139/o86-073] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
The incorporation of 125I, using lactoperoxidase, and the subsequent inactivation of beta-galactosidase in the period when incorporation and inactivation were stoichiometric were investigated in detail. The high pressure liquid chromatographic (HPLC) radioactive profiles of the tryptic peptides of samples taken in the stoichiometric period showed that, although two labelled peptides predominated, there were other labelled peptides. The predominating peptides were shown to be the mono- and di-iodinated forms of the peptide containing Tyr-253. This confirmed the result of an earlier study, but quantitation showed that this iodination accounted for only 15-18% of the total. To show that the other labelled peptides in the HPLC profiles were not merely oxidized or partially digested forms of the peptide containing Tyr-253, two experiments were carried out. In one of the experiments, two of the other labelled peptides were isolated and identified as iodinated forms of the peptide containing Tyr-285 (5-7% of the incorporation). In the other experiment, four additional labelled fractions from the HPLC eluate were treated further with trypsin. No further digestion was observed and thus these peptides did not result from incomplete digestion of the sequence containing Tyr-253. Overall, these results show that, although the incorporation of 125I was stoichiometric with inactivation, no single Tyr was responsible for the inactivation as was tentatively suggested previously. The competitive inhibitor isopropyl-beta-D-thiogalactopyranoside (IPTG) was effective in reducing the rates of inactivation of the enzyme and incorporation of 125I, but the same peptides were labelled in the presence of IPTG as in its absence.
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Muhitch MJ, Edwards LA, Fletcher JS. Influence of diamines and polyamines on the senescence of plant suspension cultures. Plant Cell Rep 1983; 2:82-84. [PMID: 24257954 DOI: 10.1007/bf00270171] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/1982] [Indexed: 06/02/2023]
Abstract
The diamines putrescine and cadaverine and the polyamines spermine and spermidine inhibited the senescence of nonphotosynthetic cultures of Paul's Scarlet rose. Response was observed when the media of stationary phase cultures was adjusted to either 1 mM of cadaverine or putrescine; or 0.1 μM of either spermine or spermidine along with 2% sucrose in all cases. Senescence of the cultures was followed by microscopic examination of cell aliquots removed at 10 day intervals and treated with the vital stain, fluorescein diacetate.
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Affiliation(s)
- M J Muhitch
- Department of Botany and Microbiology, University of Oklahoma, 73019, Norman, OK, USA
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Edwards LA. Symposium on diarrhea. 6. Infectious diarrhea. Can Med Assoc J 1977; 116:753-5. [PMID: 849557 PMCID: PMC1879424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Diarrhea may be primarily infectious in origin. Causes can be conveniently classified according to the etiologic agent, which may be viral, chlamydial, bacterial, protozoal, helminthic or fungal. The most common type of infectious diarrhea in Canada is viral. Bacterial infection, particularly staphylococcal and salmonellal, also is relatively common.
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Abstract
Two cases of meglumine iodipamide (Cholografin) hepatotoxicity were confirmed by liver biopsy. The hepatic lesion was centrilobular in location and resolved within a short period of time. Nausea and vomiting commonly reported after intravenous cholangiography may be clinical manifestations of this entity.
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Edwards LA, Hilliard JR, Wood DE. Axillary vein thrombosis and pulmonary embolism possibly due to oral contraception. Can Med Assoc J 1969; 100:78-80. [PMID: 5762476 PMCID: PMC1945510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Hawley CA, Detmer JE, Edwards LA. An electronic data processing method for rapid assessment of potential off-site radiological effects. Health Phys 1966; 12:1356-1362. [PMID: 5970988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
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