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Jackson E, Duchatel R, Persson M, Mannan A, Yadavilli S, Parackal S, Game S, Chong WC, Jayasekara S, Le Grand M, Kearney P, Douglas A, Findlay I, Staudt D, Germon Z, Skerrett-Byrne D, Nixon B, Smith N, Hulleman E, Day B, McCowage G, Alvaro F, Waszak S, Larsen M, Colino-Sanguino Y, Valdes-Mora F, Rakotomalala A, Meignan S, Pasquier E, Vitanza N, Nazarian J, Koschmann C, Cain J, Mueller S, Dun M. EXTH-12. PRECLINICAL AND CASE STUDY EXAMINATION OF THE COMBINATION OF THE CLPP AGONIST ONC201 WITH THE PI3K/AKT INHIBITOR PAXALISIB FOR THE TREATMENT OF DIFFUSE MIDLINE GLIOMA. Neuro Oncol 2022. [PMCID: PMC9660771 DOI: 10.1093/neuonc/noac209.811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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] Open
Abstract
Abstract
Diffuse midline gliomas (DMGs), including those of the pons (diffuse intrinsic pontine glioma - DIPG), are pediatric CNS tumors recognized as the most lethal of all children’s cancers. Palliative radiotherapy remains the only approved treatment, with survival just 9-11 months post-diagnosis. The brain-penetrant small molecule therapy, ONC201, shows preclinical and emerging efficacy in early-stage clinical trials. However, patients invariably develop resistance, with some patients and models completely refractory to treatment. Using a powerful combination of pharmacology, proteomics, genomics, epigenetics, in vitro and in vivo modeling, across ten international laboratories, we have uncovered mechanisms underpinning resistance to ONC201. We find ONC201 elicits antagonism of the Dopamine receptor D2 (DRD2), whilst also causing mitochondrial degradation through potent agonism of the mitochondrial protease CLPP. This drives proteolysis of the electron transport chain (ETC) proteins including Succinate dehydrogenase A (SDHA) and the critical mitochondrial tricarboxylic acid (TCA) cycle regulator, Isocitrate dehydrogenase 3B (IDH3B). Loss of TCA activity reduces α-ketoglutarate and inhibits lysine demethylation, increasing methylation of H3K4me3 and H3K27me3, thus, altering the epigenome of DIPG. Mitochondrial disruption elicited redox-activated RAS-PI3K/AKT signaling, counteracted using the PI3K/AKT inhibitor paxalisib. The combination of ONC201 and paxalisib synergistically extended survival of two aggressive DIPG PDX models (SU-DIPG-VI vehicle=73 vs. combination=100-days, p=0.0027; SF8626 vehicle=36 vs. combination=43-days, p=0.0002). Compassionate access to this combination (n=2 patients; immediately post-RT and following re-RT) resulted in dramatic reductions in tumor volume, extending overall survival for the patient at diagnosis and the patient at progression (e.g., MR axial diagnosis scan = 1554 mm2, following twelve months on the combination, current tumor volume = 464 mm2 (~70% reduction), patient remains in progression free survival, 15 months since diagnosis). The clinical utility of our preclinical data is currently under investigation in the PNOC022 clinical trial (NCT05009992).
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Affiliation(s)
- Evangeline Jackson
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - Ryan Duchatel
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - Mika Persson
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - Abdul Mannan
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - Sridevi Yadavilli
- Center for Genetic Medicine Research, Children’s National Hospital , Washington, DC , USA
| | - Sarah Parackal
- Hudson Institute of Medical Research , Clayton, VIC , Australia
| | - Shaye Game
- Hudson Institute of Medical Research , Clayton, VIC , Australia
| | - Wai Chin Chong
- Hudson Institute of Medical Research , Clayton, VIC , Australia
| | | | - Marion Le Grand
- Laboratoire d’Oncologie Prédictive, CRCM, Institut Paoli-Calmettes, Aix-Marseille Université, Département d’Oncologie Médicale, Institut Paoli-Calmettes, Marseille, France , Marseille , France
| | - Padraic Kearney
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - Alicia Douglas
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - Izac Findlay
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - Dilana Staudt
- 1 Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - Zacary Germon
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
| | - David Skerrett-Byrne
- Infertility and Reproduction Research Program, Hunter Medical Research Institute, New Lambton Heights, NSW , Australia
| | - Brett Nixon
- Infertility and Reproduction Research Program, Hunter Medical Research Institute, New Lambton Heights, NSW , Australia
| | - Nathan Smith
- Analytical and Biomolecular Research Facility Advanced Mass Spectrometry Unit, University of Newcastle , Callaghan, NSW , Australia
| | - Esther Hulleman
- Princess Máxima Center for Pediatric Oncology, Utrecht, Netherlands , Utrecht , Netherlands
| | - Bryan Day
- QIMR Berghofer Medical Research Institute , Herston, QLD , Australia
| | - Geoffrey McCowage
- Sydney Children's Hospitals Network , Westmead, New South Wales , Australia
| | - Frank Alvaro
- Precision Medicine Program, Hunter Medical Research Institute, New Lambton Heights, NSW , Australia
| | - Sebastian Waszak
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo and Oslo University Hospital, Oslo, Norway , Oslo , Norway
| | - Martin Larsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark, Odense M, Denmark , Odense M , Denmark
| | - Yolanda Colino-Sanguino
- Cancer Epigenetics Biology and Therapeutics, Precision Medicine Theme, Children’s Cancer Institute , Sydney, NSW , Australia
| | - Fatima Valdes-Mora
- Cancer Epigenetics Biology and Therapeutics, Precision Medicine Theme, Children’s Cancer Institute , Sydney, NSW , Australia
| | - Andria Rakotomalala
- Tumorigenesis and Resistance to Treatment Unit, Centre Oscar Lambret, F-59000 Lille, France, F-59000 Lille, France
| | - Samuel Meignan
- Tumorigenesis and Resistance to Treatment Unit, Centre Oscar Lambret, F-59000 Lille, France , F-59000 Lille , France
| | - Eddy Pasquier
- Laboratoire d’Oncologie Prédictive, CRCM, Institut Paoli-Calmettes, Aix-Marseille Université, Département d’Oncologie Médicale, Institut Paoli-Calmettes, Marseille, France , Marseille , France
| | - Nicholas Vitanza
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute , Seattle, WA , USA
| | - Javad Nazarian
- Department of Oncology, Children’s Research Center, University Children’s Hospital Zurich, Zurich, Switzerland , Zurich , Switzerland
| | - Carl Koschmann
- Department of Pediatrics, Michigan Medicine , Ann Arbor, MI , USA
| | - Jason Cain
- Hudson Institute of Medical Research , Clayton, VIC , Australia
| | - Sabine Mueller
- UCSF Helen Diller Family Comprehensive Cancer Center, University of California, San Francisco , San Francisco, CA , USA
| | - Matthew Dun
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
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Dun MD, Jackson ER, Duchatel RJ, Persson ML, Mannan A, Yadavilli S, Parackal S, Game S, Chong WC, Jayasekara S, Le Grand M, Kearney PS, Douglas AM, Findlay IJ, Staudt D, Germon ZP, Skerrett-Byrne DA, Nixon B, Smith ND, Hulleman E, Day B, McCowage GB, Alvaro F, Waszak SM, Larsen MR, Colino-Sanguino Y, Valdes-Mora F, Rakotomalala A, Meignan S, Pasquier E, Vitanza NA, Nazarian J, Koschmann C, Cain J, Mueller S. DIPG-07. Preclinical and case study results underpinning the phase II clinical trial testing the combination of ONC201 and paxalisib for the treatment of patients with diffuse midline glioma (NCT05009992). Neuro Oncol 2022. [DOI: 10.1093/neuonc/noac079.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Diffuse midline gliomas (DMG), including those of the brainstem (diffuse intrinsic pontine glioma - DIPG), are pediatric CNS tumors recognized as the most lethal of all children’s cancers. Palliative radiotherapy is the only approved treatment, with survival just 9-11–months post-diagnosis. ONC201 shows preclinical and emerging clinical efficacy in early-stage clinical trials, extending survival of DIPG patients by ~9-11–months compared to historic controls. However, patients invariably develop resistance, with some patients completely refractory to treatment. Using a multi-omics approach, including pharmacology, proteomics, genomics, epigenetics, in vitro and in vivo modeling, across ten international laboratories, we have uncovered the inherent mechanisms of resistance to ONC201. We find ONC201 elicits antagonism of the Dopamine receptor D2 (DRD2), whilst also causing mitochondrial degradation through potent agonism of the Mitochondrial protease CLPP, that drives proteolysis of the electron transport chain (ETC) protein Succinate dehydrogenase A (SDHA) and degradation of critical mitochondrial tricarboxylic acid (TCA) cycle regulator Isocitrate dehydrogenase 3B (IDH3B). Loss mitochondrial respiration increased hypoxia and reduced α-ketoglutarate, inhibiting lysine demethylation, increasing methylation of H3K4me3 and H3K27me3, thus altering the epigenome of primary DIPG cells. Loss of SDHA caused oxidation of succinate forming superoxide driving redox regulated PI3K/AKT signaling, counteracted using the PI3K/AKT inhibitor paxalisib. The combination of ONC201 and paxalisib synergically extended survival of two aggressive DIPG PDX models (SU-SIPG-VI vehicle=73 vs. combination=100-days, p=0.0027; SF8626 vehicle=36 vs. combination=43-days, p=0.0002). Compassionate access to this combination (n=2 patients; immediately post-RT and following re-RT) resulted in reductions in tumor volume and complete resolution of disease symptoms, extending overall survival (e.g., diagnosis patient MR axial scan=1554 mm2 , following eight months on the combination, current tumor volume=464 mm2 (<70%), patient remains on treatment). Our findings harness the powerful anti-DMG/DIPG pharmacokinetic/dynamic properties of ONC201 and paxalisib, a combination that is currently in clinical trials (NCT05009992).
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Affiliation(s)
- Matthew D Dun
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Evangeline R Jackson
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Ryan J Duchatel
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Mika L Persson
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Abdul Mannan
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Sridevi Yadavilli
- Center for Genetic Medicine Research, Children’s National Hospital , Washington, DC , USA
- Brain Tumor Institute, Children’s National Hospital , Washington, DC , USA
| | - Sarah Parackal
- Hudson Institute of Medical Research , Clayton, VIC , Australia
- Department of Molecular and Translational Science, Monash University , Clayton, VIC , Australia
| | - Shaye Game
- Hudson Institute of Medical Research , Clayton, VIC , Australia
- Department of Molecular and Translational Science, Monash University , Clayton, VIC , Australia
| | - Wai Chin Chong
- Hudson Institute of Medical Research , Clayton, VIC , Australia
- Department of Molecular and Translational Science, Monash University , Clayton, VIC , Australia
| | - Samantha Jayasekara
- Hudson Institute of Medical Research , Clayton, VIC , Australia
- Department of Molecular and Translational Science, Monash University , Clayton, VIC , Australia
| | - Marion Le Grand
- Laboratoire d’Oncologie Prédictive, CRCM, Institut Paoli-Calmettes, Aix-Marseille Université, Département d’Oncologie Médicale, Institut Paoli-Calmettes , Marseille , France
- Centre de Recherche en Cancérologie de Marseille, Aix-Marseille Université, Inserm, CNRS, Institut Paoli Calmettes , Marseille , France
| | - Padraic S Kearney
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Alicia M Douglas
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Izac J Findlay
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Dilana Staudt
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - Zacary P Germon
- Cancer Signalling Research Group, School of Biomedical Sciences and Pharmacy, College of Health, Medicine and Wellbeing, University of Newcastle , Callaghan, NSW , Australia
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
| | - David A Skerrett-Byrne
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, The University of Newcastle , Callaghan, NSW , Australia
| | - Brett Nixon
- Priority Research Centre for Reproductive Science, School of Environmental and Life Sciences, The University of Newcastle , Callaghan, NSW , Australia
| | - Nathan D Smith
- Analytical and Biomolecular Research Facility Advanced Mass Spectrometry Unit, University of Newcastle , Callaghan, NSW , Australia
| | - Esther Hulleman
- Princess Máxima Center for Pediatric Oncology , Utrecht , Netherlands
| | - Bryan Day
- QIMR Berghofer Medical Research Institute , Herston, QLD , Australia
| | - Geoff B McCowage
- Department of Oncology, The Children's Hospital at Westmead , Westmead, NSW , Australia
| | - Frank Alvaro
- Precision Medicine Research Program, Hunter Medical Research Institute, New Lambton Heights , NSW , Australia
- John Hunter Children’s Hospital, New Lambton Heights , NSW , Australia
| | - Sebastian M Waszak
- Centre for Molecular Medicine Norway (NCMM), Nordic EMBL Partnership, University of Oslo and Oslo University Hospital , Oslo , Norway
- Department of Neurology, University of California, San Francisco , CA , USA
| | - Martin R Larsen
- Department of Biochemistry and Molecular Biology, University of Southern Denmark , Odense M , Denmark
| | - Yolanda Colino-Sanguino
- Cancer Epigenetics Biology and Therapeutics, Precision Medicine Theme, Children’s Cancer Institute , Sydney, NSW , Australia
- School of Children and Women Health, University of NSW , Sydney, NSW , Australia
| | - Fatima Valdes-Mora
- Cancer Epigenetics Biology and Therapeutics, Precision Medicine Theme, Children’s Cancer Institute , Sydney, NSW , Australia
- School of Children and Women Health, University of NSW , Sydney, NSW , Australia
| | - Andria Rakotomalala
- Tumorigenesis and Resistance to Treatment Unit, Centre Oscar Lambret, F-
- Lille, France, Univ. Lille, CNRS, Inserm, CHU Lille, UMR-U- CANTHER – Cancer Heterogeneity Plasticity and Resistance to Therapies, F-59000, Lille, France
| | - Samuel Meignan
- Tumorigenesis and Resistance to Treatment Unit, Centre Oscar Lambret, F-
- Lille, France, Univ. Lille, CNRS, Inserm, CHU Lille, UMR-U- CANTHER – Cancer Heterogeneity Plasticity and Resistance to Therapies, F-59000, Lille, France
| | - Eddy Pasquier
- Centre de Recherche en Cancérologie de Marseille, Aix-Marseille Université, Inserm, CNRS, Institut Paoli Calmettes , Marseille , France
- Metronomics Global Health Initiative , Marseille , France
| | - Nicholas A Vitanza
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute , Seattle, WA , USA
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, Seattle Children’s Hospital , Seattle, WA , USA
| | - Javad Nazarian
- Department of Oncology, Children’s Research Center, University Children’s Hospital Zürich , Zurich , Switzerland
- The George Washington University, School of Medicine and Health Sciences , Washington, DC , USA
| | - Carl Koschmann
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, University of Michigan, Ann Arbor , MI , USA
| | - Jason Cain
- Hudson Institute of Medical Research , Clayton, VIC , Australia
- Department of Molecular and Translational Science, Monash University , Clayton, VIC , Australia
| | - Sabine Mueller
- Department of Oncology, Children’s Research Center, University Children’s Hospital Zürich , Zurich , Switzerland
- Pediatric Hematology-Oncology and Neurology, UCSF Benioff Children’s Hospital , CA , USA
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Parackal S, Bradshaw G, Sun C, Chong WC, Daniel P, Jayasekara S, Crombie D, Firestein R, Cain J. Abstract 3029: Functional genomics pipeline reveals therapeutic dependencies in diffuse intrinsic pontine glioma. Cancer Res 2021. [DOI: 10.1158/1538-7445.am2021-3029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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
Abstract
Diffuse intrinsic pontine glioma (DIPG) is a highly aggressive and infiltrative pediatric brainstem tumor with universal lethality. Current treatment is limited to palliative radiotherapy. Molecular characterization of DIPG has revealed recurrent heterozygous mutation (p.K27M) in the Histone H3 variant genes; H3.1 (HIST1H3B, HIS1H3C) or H3.3 (H3F3A) in >80% of cases. While H3K27M function is still under heavy investigation, accumulating molecular evidence now suggests its subsequent role in tumorigenesis is driven through epigenetic dysregulation of the chromatin via the loss of tri-methylation markers. Co-occurring mutations in known oncogenes and amplification in cancer prone proliferative pathways further contribute to the DIPG's diverse molecular landscape and may represent therapeutic vulnerabilities. The purpose of this present study is to utilize a functional genomics pipeline to investigate the intrinsic molecular mechanisms of H3K27M DIPG. Identification of novel molecular dependencies and pathways that contribute to overall disease progression serve as potential targets for therapeutic exploitation and development for clinical utility. Sixteen established and validated patient derived cell lines (10 H3.3K27M, 4 H3.1K27M and 2 Wt), obtained from external collaborators were used in this study. High throughput screening for DIPG drug sensitivity was carried out using a panel of 2048 molecular compounds. Cell viability data following 72 hours treatment was z- score transformed and potential compounds identified based on a z-score ≤-1.5 and no effect in a neural stem cell (NSC) control line. Highly prevalent targets identified from this primary screen include HDAC, Proteasome, Topoisomerase and Microtubule Associated inhibitors. In parallel, a 300 gene pooled CRISPR/Cas9 loss of function screen was used to determine key DIPG survival dependencies. Cas9 expressing DIPG cell lines (3 H3.1K27M and 3 H3.3K27M) were transduced with 1200 gRNAs and cultured for 21-28 day period. Next Generation Sequencing (NGS) of samples was used to determine gRNA depletion and a set z score threshold of ≤-1.5 to distinguish potential “hits”. Hierarchical clustering revealed genotype specific patterns suggesting differing tumorigenic mechanisms between H3.1 and H3.3 K27M DIPG. Comparison between CRISPR and drug screens revealed 24 molecular targets with therapeutic sensitivity and DIPG cell survival dependency. We are currently carrying out validation studies of these targets for therapeutic development, effectively demonstrating a functional genomics pipeline is able to identify therapeutic dependencies in DIPG.
Citation Format: Sarah Parackal, Gabrielle Bradshaw, Claire Sun, Wai Chin Chong, Paul Daniel, Samantha Jayasekara, Duncan Crombie, Ron Firestein, Jason Cain, Department of Molecular Translational Science, Monash University. Functional genomics pipeline reveals therapeutic dependencies in diffuse intrinsic pontine glioma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3029.
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Affiliation(s)
- Sarah Parackal
- Hudson Institute of Medical Research, Melbourne, Australia
| | | | - Claire Sun
- Hudson Institute of Medical Research, Melbourne, Australia
| | - Wai Chin Chong
- Hudson Institute of Medical Research, Melbourne, Australia
| | - Paul Daniel
- Hudson Institute of Medical Research, Melbourne, Australia
| | | | - Duncan Crombie
- Hudson Institute of Medical Research, Melbourne, Australia
| | - Ron Firestein
- Hudson Institute of Medical Research, Melbourne, Australia
| | - Jason Cain
- Hudson Institute of Medical Research, Melbourne, Australia
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Parackal S, Chong WC, Bradshaw G, Sun C, Daniel P, Roussel E, Jayasekara S, Crombie D, Firestein R, Cain J. DIPG-18. IDENTIFICATION OF TARGETABLE PATHWAY DEPENDENCIES IN DIFFUSE INTRINSIC PONTINE GLIOMA. Neuro Oncol 2020. [PMCID: PMC7715817 DOI: 10.1093/neuonc/noaa222.068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Diffuse Intrinsic Pontine Glioma (DIPG) is a highly aggressive paediatric brainstem tumour with a dismal prognosis. Recurrent heterozygous mutations (p.K27M) in Histone H3 variant genes have been identified in the majority of DIPG cases. While the exact mechanism of H3K27M’s function is poorly understood, evidence suggests a role for epigenetic dysregulation in disease pathogenesis. This study aims to use functional genomics to identify novel therapeutic dependencies in H3K27M DIPG. DIPG drug sensitivity screening was carried out in twelve established and validated patient derived cell lines (10 H3.3K27M and 2 Wt) using an FDA approved drug library containing 1480 compounds. Highly prevalent targets identified from this screen include HDAC, microtubule, proteasome and CDK inhibitors. Additionally, a custom pooled CRISPR knockout library of druggable targets (300 genes, 1200 guide RNAs) was used to identify key DIPG cell survival pathways. To date five DIPG cell lines (1 Wt; 1 H3.1; 3 H3.3) have undergone screening. Knockdown of known DIPG driver genes (TP53; PDGFRA; PIK3CA and PIK3CR1) resulted in reduced cell viability, consistent with their proposed function and validating knockout screen utility. Preliminary data demonstrates Wt and H3K27M DIPGs cluster independently based on genes required for survival, suggesting differing tumorigenesis mechanisms and the potential for therapeutically targeting genotype specific pathways. Correlation of parallel drug screen and RNA-seq data will potentially reveal H3-dependent pathways for therapeutic exploitation. Collectively, we show a functional genomics approach is able to identify genotype-specific pathway dependencies in DIPG, paving the way for molecularly informed personalized therapies for patients.
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Affiliation(s)
- Sarah Parackal
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Wai Chin Chong
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Gabrielle Bradshaw
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Claire Sun
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Paul Daniel
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Enola Roussel
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Genetics, School of Biological Sciences, Faculty of Science, Monash University
| | - Samantha Jayasekara
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Duncan Crombie
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Ron Firestein
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
| | - Jason Cain
- Centre for Cancer Research, Hudson Institute of Medical Research, Department of Molecular Translational Science, School of Clinical Sciences, Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC, Australia
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Przystal* JM, Yadavilli* S, Abadi* CC, Yadav VN, Laternser S, Cosentino CC, Waszak SM, Cartaxo R, Biery M, Myers C, Jayasekara S, Olson JM, Filbin MG, Vitanza NA, Cain J, Koschmann# C, Müller# S, Nazarian# J. DIPG-64. INTERNATIONAL PRECLINICAL DRUG DISCOVERY AND BIOMARKER PROGRAM INFORMING AN ADOPTIVE COMBINATORIAL TRIAL FOR DIFFUSE MIDLINE GLIOMAS. Neuro Oncol 2020. [PMCID: PMC7715218 DOI: 10.1093/neuonc/noaa222.109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
INTRODUCTION DMG-ACT (DMG- multi-arm Adaptive and Combinatorial Trial) aims to implement a highly innovative clinical trial design of combinatorial arms for patients with diffuse midline gliomas (DMGs) at all disease stages that is adaptive to pre-clinical data generated in eight collaborating institutions. The goals of the team are to: i) rapidly identify and validate promising drugs for clinical use, and ii) predict biomarkers for promising drugs. METHODS In vitro (n=15) and in vivo (n=8) models of DMGs across seven institutions were used to assess single and combination treatments with ONC201, ONC206, marizomib, panobinostat, Val-083, and TAK228. In vivo pharmacokinetic assays using clinically relevant dosing of ONC201, ONC206, and panobinostat were performed. Predictive biomarkers for ONC201 and ONC206 were identified using extensive molecular assays including CRISPR, RNAseq, ELISA, FACS, and IHC. RESULTS Inhibitory concentrations (IC50) were established and validated across participating sites. In vivo validation of single and combination drug assays confirmed drug efficacy as increased survival for: ONC201 (p=0.01), ONC206 (p=0.01), ONC201+ONC206 (p=0.02), and ONC201+panobinostat (p=0.01). Marizomib showed toxicity in murine/zebrafish PDXs models. Murine pharmacokinetic analysis showed peak brain levels of ONC201 and ONC206 above pre-clinical IC50. Molecular testing and analyses of existing drug screen across 537 cancer cell lines validated mitochondrial stress and ATF4 as the main targets induced by ONC201/6. CONCLUSION Thorough preclinical testing in a multi-site laboratory setting is feasible and identified ONC201 in combination with ONC206 as promising therapeutics for DMGs. Preclinical and correlative-clinical studies are ongoing.
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Affiliation(s)
- Justyna M Przystal*
- Oncology Department, University Children’s Hospital Zurich, Zürich, Switzerland
| | - Sridevi Yadavilli*
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington DC, USA
| | | | | | - Sandra Laternser
- Oncology Department, University Children’s Hospital Zurich, Zürich, Switzerland
| | | | | | - Rodrigo Cartaxo
- Department of Pediatrics, Michigan Medicine, Ann Arbor, MI, USA
| | - Matt Biery
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Carrie Myers
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Samantha Jayasekara
- Developmental and Cancer Biology Centre for Cancer Research Hudson Institute of Medical Research, Melbourne, Australia
| | - James M Olson
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Mariella G Filbin
- Department of Pediatric Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Broad Institute of Harvard and MIT, Cambridge, MA, USA
| | - Nicholas A Vitanza
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Division of Pediatric Hematology/Oncology, Department of Pediatrics, University of Washington, Seattle Children’s Hospital, Seattle, WA, USA
| | - Jason Cain
- Developmental and Cancer Biology Centre for Cancer Research Hudson Institute of Medical Research, Melbourne, Australia
| | - Carl Koschmann#
- Department of Pediatrics, Michigan Medicine, Ann Arbor, MI, USA
| | - Sabine Müller#
- Oncology Department, University Children’s Hospital Zurich, Zürich, Switzerland
- UCSF Department of Neurology, Neurosurgery and Pediatrics, San Francisco, California, USA
| | - Javad Nazarian#
- Oncology Department, University Children’s Hospital Zurich, Zürich, Switzerland
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington DC, USA
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Przystal J, Yadavilli S, Abadi CC, Yadav VN, Laternser S, Cosentino CC, Waszak S, Cartaxo R, Biery M, Myers C, Jayasekara S, Olson J, Filbin M, Vitanza N, Cain J, Koschmann C, Mueller S, Nazarian J. DDRE-03. INTERNATIONAL PRECLINICAL DRUG DISCOVERY AND BIOMARKER PROGRAM INFORMING AN ADOPTIVE COMBINATORIAL TRIAL FOR DIFFUSE MIDLINE GLIOMAS. Neuro Oncol 2020. [DOI: 10.1093/neuonc/noaa215.248] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
INTRODUCTION
DMG-ACT (DMG- multi-arm Adaptive and Combinatorial Trial) aims to implement a highly innovative clinical trial design of combinatorial arms for patients with diffuse midline gliomas (DMGs) at all disease stages that is adaptive to pre-clinical data generated in ten collaborating institutions. Novel drug and drug combination were tested, predictive biomarkers were identified and incorporated in clinical trial design.
METHODS
In vitro (n=15) and in vivo (n=8) models of DMGs across ten institutions were used to assess single and combination treatments with ONC201, ONC206, marizomib, panobinostat, 5-Azacytidine, Val-083, GDC0084 and TAK228. In vivo drug toxicity screenings were conducted using larval zebrafish model and murine PDX models. Predictive biomarkers for ONC201 and ONC206 were identified using meta-analysis, and extensive molecular assays including CRISPR, RNAseq, FACS, and IHC.
RESULTS
Inhibitory concentrations (IC50) were established and validated multiple preclinical models. ONC201 and ONC206, ONC201 and TAK228, ONC201 and GDC0084 showed synergism. In vivo survival assays showed increased survival for: ONC201 (p=0.01), ONC206 (p=0.01), ONC201+ONC206 (p=0.02), and ONC201+panobinostat (p=0.01). Marizomib showed toxicity in murine/zebrafish PDXs models. Murine pharmacokinetic analysis showed peak brain levels of ONC201 and ONC206 above pre-clinical IC50. Molecular testing and analyses of existing drug screen across 537 cancer cell lines validated mitochondrial protease ClpP and ATF4 as ONC201/6 targets. Predictive biomarkers of response to drug were identified.
CONCLUSION
Thorough preclinical testing in a multi-site laboratory setting is feasible and identified ONC201 in combination with ONC206, TAK228 and GDC0084 as promising therapeutics for DMGs.
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Affiliation(s)
| | - Sridevi Yadavilli
- Center for Genetic Medicine Research, Children’s National Medical Center, Washington, DC, USA
| | | | | | - Sandra Laternser
- Oncology Department, University Children’s Hospital Zurich, Zurich, Switzerland
| | | | | | | | - Matt Biery
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Carrie Myers
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Samantha Jayasekara
- Developmental and Cancer Biology Centre for Cancer Research Hudson Institute of Medical Research, Melbourne, Australia
| | - James Olson
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Mariella Filbin
- Dana-Farber Boston Children’s Cancer and Blood Disorders Center, Boston, MA, USA
| | | | - Jason Cain
- Developmental and Cancer Biology Centre for Cancer Research Hudson Institute of Medical Research, Melbourne, Australia
| | - Carl Koschmann
- University of Michigan Medical School, Ann Abor, MI, USA
| | - Sabine Mueller
- University of California, San Francisco, San Francisco, CA, USA
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Popovski D, Cochrane C, Algar E, Szczepny A, Jayasekara S, Ashley D, Downie P, Watkins N, Cain J. ATRT-03. TARGETED CATALYTIC INHIBITION OF EZH2 SYNERGIZES WITH LOW-DOSE PANOBINOSTAT IN MALIGNANT RHABDOID TUMOR. Neuro Oncol 2017. [DOI: 10.1093/neuonc/nox083.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Lazarus KA, Brown K, Young M, Cain J, Jayasekara S, Coulson R, Watkins N, Clyne C, Chand A. Abstract 76: Liver receptor homologue-1 increases incidence of DMBA-induced mammary tumors. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-76] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [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
Abstract
Breast cancer is one of the most common malignancies globally. It accounts for approximately 15% of cancer-related deaths in Australian women. The orphan nuclear receptor liver receptor homolog-1 (LRH-1) promotes increased cell proliferation, motility and invasion in breast cancer cell lines. Additionally, high LRH-1 expression in human breast cancers is positively associated with estrogen receptor alpha status and aromatase activity. However, the role of LRH-1 in tumour growth is not well understood. Therefore, we aimed to generate a doxycycline (dox)-inducible mammary epithelial specific LRH-1 knock-in mouse in order to define the role of LRH-1 in mammary epithelial proliferation in vivo. In addition, the Dimethylbenz(a)anthracene (DMBA) induced mammary tumour model was utilized with the LRH-1 transgenic mice to determine the role LRH-1 plays in promoting mammary carcinogenesis. Given clear in vitro roles for LRH-1 in breast cancer cell proliferation, we hypothesise LRH-1 stimulates mouse mammary epithelial cell proliferation and promotes DMBA-mediated mammary tumorigenesis.
We demonstrate increase in proliferation markers Ki-67, PCNA and PH3 immunoreactivity in luminal epithelial cells of dox-treated animals indicating that LRH-1 plays a role in mammary cell proliferation in vivo. In DMBA treated animals, we observed a five-fold increase of dense pre-neoplastic epithelial foci (p=0.0267), and a four-fold increase in microscopic lesions in dox-treated animals (p=0.0003). We also demonstrated that LRH-1 over-expression significantly reduced breast tumour-free survival in the transgenic DMBA model (no dox n=11; dox n=12, Mantel-Cox test p=0.0375). Tumour penetrance in DMBA animals not treated with dox was 9% (out of eleven animals) versus 25.0% (out of twelve animals) in the dox treated cohort.
LRH-1 is known synergise with β-catenin to induce cyclin D1/E1 mediated cell proliferation in vitro. We analysed transcript levels of cyclin D1/E1 and show a significant increase in dox treated animals with or without DMBA. Finally, we demonstrate an increase in the oncogene β-catenin nuclear localisation in the dox treated animals with or without DMBA. Taken together, these data suggest that LRH-1 increases incidence of DMBA-induced mammary tumours. Further analyses on mechanism(s) mediated by LRH-1 are warranted to fully understand its role in mammary tumorigenesis.
Note: This abstract was not presented at the meeting.
Citation Format: Kyren A. Lazarus, Kristy Brown, Morag Young, Jason Cain, Samantha Jayasekara, Rhiannon Coulson, Neil Watkins, Colin Clyne, Ashwini Chand. Liver receptor homologue-1 increases incidence of DMBA-induced mammary tumors. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 76. doi:10.1158/1538-7445.AM2014-76
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Bertozzi AI, Munzer C, Fouyssac F, Andre N, Boetto S, Leblond P, Bourdeaut F, Dufour C, Deshpande RK, Bhat KG, Mahalingam S, Muscat A, Cain J, Ferguson M, Popovski D, Algar E, Rossello FJ, Jayasekara S, Watkins DN, Hodge J, Ashley D, Hishii M, Saito M, Arai H, Han ZY, Richer W, Lucchesi C, Freneaux P, Nicolas A, Grison C, Pierron G, Delattre O, Bourdeaut F, Epari S, TS N, Gupta T, Chinnaswamy G, Sastri JG, Shetty P, Moiyadi A, Jalali R, Fay-McClymont T, Johnston D, Janzen L, Guger S, Scheinemann K, Fleming A, Fryer C, Hukin J, Mabbott D, Huang A, Bouffet E, Lafay-Cousin L, Kawamura A, Yamamoto K, Nagashima T, Bartelheim K, Benesch M, Buchner J, Gerss J, Hasselblatt M, Kortmann RD, Fleischack G, Quiroga E, Reinhard H, Schneppenheim R, Seeringer A, Siebert R, Timmermann B, Warmuth-Metz M, Schmid I, Fruhwald MC, Fruhwald MC, Bartelheim K, Seeringer A, Kerl K, Kortmann RD, Warmuth-Metz M, Hasselblatt M, Schneppenheim R, Siebert R, Klingebiel T, Al-Kofide A, Khafaga Y, Al-Hindi H, Dababo M, Ul-Haq A, Anas M, Barria MG, Siddiqui K, Hassounah M, Ayas M, Al-Shail E, Hasselblatt M, Jeibmann A, Eikmeier K, Linge A, Johann P, Koos B, Bartelheim K, Kool M, Pfister SM, Fruhwald MC, Paulus W, Hasselblatt M, Schuller U, Junckerstorff R, Rosenblum MK, Alassiri AH, Rossi S, Bartelheim K, Schmid I, Gottardo N, Toledano H, Viscardi E, Witkowski L, Nagel I, Oyen F, Foulkes WD, Paulus W, Siebert R, Schneppenheim R, Fruhwald MC, Schrey D, Malietzis G, Chi S, Dufour C, Lafay-Cousin L, Marshall L, Carceller F, Moreno L, Zacharoulis S, Bhardwaj R, Chakravadhanula M, Ozals V, Hampton C, Metpally R, Grillner P, Asmundsson J, Gustavsson B, Holm S, Johann PD, Korshunov A, Ryzhova M, Kerl K, Milde T, Witt O, Jones DTW, Hovestadt V, Gajjar A, Hasselblatt M, Fruhwald M, Pfister S, Kool M, Finetti M, Pons ADC, Selby M, Smith A, Crosier S, Wood J, Skalkoyannis B, Bailey S, Clifford S, Williamson D, Seeringer A, Bartelheim K, Kerl K, Hasselblatt M, Rutkowski S, Timmermann B, Kortmann RD, Schneppenheim R, Warmuth-Metz M, Gerss J, Siebert R, Graf N, Boos J, Nysom K, Fruhwald MC, Kerl K, Moreno N, Holsten T, Ahlfeld J, Mertins J, Hotfilder M, Kool M, Bartelheim K, Schleicher S, Handgretinger R, Fruhwald M, Meisterernst M, Kerl K, Schmidt C, Ahlfeld J, Moreno N, Dittmar S, Pfister S, Fruhwald M, Kool M, Meisterernst M, Schuller U, Chan GCF, Shing MMK, Yuen HL, Li RCH, Ling SL, Slavc I, Peyrl A, Chocholous M, Azizi A, Czech T, Dieckmann K, Haberler C, Leiss U, Gotti G, Biassoni V, Schiavello E, Spreafico F, Pecori E, Gandola L, Massimino M, Mertins J, Kornelius K, Moreno N, Holsten T, Fruhwald M, Kool M, Meisterernst M, Yano H, Nakayama N, Ohe N, Ozeki M, Kanda K, Kimura T, Hori T, Fukao T, Iwama T, Weil AG, Diaz A, Gernsback J, Bhatia S, Ragheb J, Niazi T, Khatib Z, Kerl K, Holsten T, Moreno N, Zoghbi A, Meisterernst AM, Birks D, Griesinger A, Amani V, Donson A, Posner R, Dunham C, Kleinschmidt-DeMasters BK, Handler M, Vibhakar R, Foreman N, Bhardwaj R, Ozals V, Hampton C, Zhou L, Catchpoole D, Chakravadhanula M, Kakkar A, Biswas A, Suri V, Sharma M, Kale S, Mahapatra A, Sarkar C, Torchia J, Picard D, Ho KC, Khuong-Quang DA, Louterneau L, Bourgey M, Chan T, Golbourn B, Cousin LL, Taylor MD, Dirks P, Rutka JT, Bouffet E, Hawkins C, Majewski J, Kim SK, Jabado N, Huang A, Chang JHC, Confer M, Chang A, Goldman S, Dunn M, Hartsell W. ATYPICAL TERATOID RHABDOID TUMOUR. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Jayasekara S, Sharma RP, Drown DB. Effects of N-ethyl,N-nitrosourea on monoamine concentrations and metabolizing enzymes in mouse brain regions. Eur J Pharmacol 1992; 228:37-44. [PMID: 1383012 DOI: 10.1016/0926-6917(92)90009-2] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
N-ethyl,N-nitrosourea is a well known alkylating agent and produces central nervous system-specific tumors in several laboratory animal species. In the present study, young male CD-1 mice were treated by i.p. injections of 0, 2, 8, or 32 mg/kg body weight N-ethyl,N-nitrosourea, twice a week for 3 weeks. Endogenous levels of brain monoamine neurotransmitters and their selected metabolites; norepinephrine (NE), dopamine (DA), 5-hydroxytryptamine (5-HT), vanillylmandelic acid (VMA), dihydroxyphenyl acetic acid (dopac), homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and dihydroxyphenylalanine (dopa) were measured using HPLC with electrochemical detection. N-ethyl,N-nitrosourea treatment caused an increase of NE and 5-HT in the hypothalamus and striatum. Increased levels of 5-HIAA were noticed in the same brain regions. Elevated levels of NE were also observed in the cerebral cortex, medulla oblongata and the cerebellum. The major metabolite of NE, VMA, was decreased in several brain regions to non-detectable levels. Histopathological examination of brain tissue did not reveal any pathologic lesions. The increases in brain amines were associated with increased activity of tryptophan hydroxylase in the hypothalamus and corpus striatum. Dopa-decarboxylase was elevated in the cerebral cortex at a low dose of N-ethyl,N-nitrosourea only, whereas the monoamine oxidase activity was unaltered. Results indicated that N-ethyl,N-nitrosourea exposure may cause an elevation of steady state levels of various biogenic amines in brain areas and these changes to some extent are consistent with the altered activity of metabolizing enzymes.
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Affiliation(s)
- S Jayasekara
- Department of Biology, Utah State University, Logan 84322
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Jayasekara S, Sharma RP, Drown DB. Immunotoxic potential of N-ethyl, N-nitrosourea (ENU) in CD1 mice. Clin Exp Immunol 1989; 77:294-8. [PMID: 2776363 PMCID: PMC1542004] [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: 01/02/2023] Open
Abstract
The immunotoxic potential of ENU, a potent and transplacental neurocarcinogen, was evaluated in male CD1 mice. The animals received i.p. injections of ENU--0, 2, 8 or 32 mg/kg body weight, in citrate-phosphate buffer, twice weekly for three weeks. Splenic lymphocytes were cultured in the presence of mitogens, lipopolysaccharide, pokeweed mitogen, concanavalin A and phytohaemagglutinin. Mixed lymphocyte cultures in the presence of allogeneic cells were also tested. Blastogenic response decreased in a dose-dependent manner, as measured by the 3H-thymidine uptake by splenocytes. Primary antibody production by splenic lymphocytes from animals challenged with a T-dependent antigen (sheep red blood cells) was stimulated at low doses but depressed at the highest dose group compared with the controls, whereas T-independent cell response showed no significant change. Our results suggest that exposure to repeated, low levels of ENU significantly alters the immune status of CD1 mice. The effects appear to be somewhat selective to T cell processes, based on in vivo responses to T-dependent and T-independent antigens.
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Affiliation(s)
- S Jayasekara
- Department of Biology, Utah State University, Logan
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