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Mishra DK, Popovski D, Morris SM, Bondoc A, Senthil Kumar S, Girard EJ, Rutka J, Fouladi M, Huang A, Olson JM, Drissi R. Preclinical pediatric brain tumor models for immunotherapy: Hurdles and a way forward. Neuro Oncol 2024; 26:226-235. [PMID: 37713135 PMCID: PMC10836771 DOI: 10.1093/neuonc/noad170] [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] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Indexed: 09/16/2023] Open
Abstract
Brain tumors are the most common solid tumor in children and the leading cause of cancer-related deaths. Over the last few years, improvements have been made in the diagnosis and treatment of children with Central Nervous System tumors. Unfortunately, for many patients with high-grade tumors, the overall prognosis remains poor. Lower survival rates are partly attributed to the lack of efficacious therapies. The advent and success of immune checkpoint inhibitors (ICIs) in adults have sparked interest in investigating the utility of these therapies alone or in combination with other drug treatments in pediatric patients. However, to achieve improved clinical outcomes, the establishment and selection of relevant and robust preclinical pediatric high-grade brain tumor models is imperative. Here, we review the information that influenced our model selection as we embarked on an international collaborative study to test ICIs in combination with epigenetic modifying agents to enhance adaptive immunity to treat pediatric brain tumors. We also share challenges that we faced and potential solutions.
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Affiliation(s)
- Deepak Kumar Mishra
- Center for Childhood Cancer Research, Nationwide Children’s Hospital, Columbus, Ohio, USA
| | - Dean Popovski
- Arthur and Sonia Labatt Brain Tumor Research Centre, Division of Haematology/Oncology, Hospital for Sick Children, Toronto, Onatario, Canada
| | - Shelli M Morris
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - Andrew Bondoc
- Arthur and Sonia Labatt Brain Tumor Research Centre, Division of Haematology/Oncology, Hospital for Sick Children, Toronto, Onatario, Canada
| | - Shiva Senthil Kumar
- Center for Childhood Cancer Research, Nationwide Children’s Hospital, Columbus, Ohio, USA
| | - Emily J Girard
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - James Rutka
- Division of Neurosurgery, Hospital for Sick Children, Toronto, Ontario, Canada
| | - Maryam Fouladi
- Pediatric Neuro-Oncology Program, Nationwide Children’s Hospital, Columbus, Ohio, USA
- The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Annie Huang
- Arthur and Sonia Labatt Brain Tumor Research Centre, Division of Haematology/Oncology, Hospital for Sick Children, Toronto, Onatario, Canada
| | - James M Olson
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute, Seattle, Washington, USA
| | - Rachid Drissi
- Center for Childhood Cancer Research, Nationwide Children’s Hospital, Columbus, Ohio, USA
- The Ohio State University College of Medicine, Columbus, Ohio, USA
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2
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Kaonis S, Smith JL, Katiyar N, Merrill M, Hyelkma T, Namciu S, Le Q, Babaeva E, Ishida T, Morris SM, Girard E, Furuyama S, Ries R, Bernstein I, Meshinchi S, Henikoff S, Meers M, Hadland B, Sarthy JF. Chromatin Profiling of CBFA2T3-GLIS2 AMLs Identifies Key Transcription Factor Dependencies and BRG1 Inhibition as a Novel Therapeutic Strategy. bioRxiv 2023:2023.08.30.555598. [PMID: 37693371 PMCID: PMC10491196 DOI: 10.1101/2023.08.30.555598] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Oncogenic fusions involving transcription factors are present in the majority of pediatric leukemias; however, the context-specific mechanisms they employ to drive cancer remain poorly understood. CBFA2T3-GLIS2 (C/G) fusions occur in treatment-refractory acute myeloid leukemias and are restricted to young children. To understand how the C/G fusion drives oncogenesis we applied CUT&RUN chromatin profiling to an umbilical cord blood/endothelial cell (EC) co-culture model of C/G AML that recapitulates the biology of this malignancy. We find C/G fusion binding is mediated by its zinc finger domains. Integration of fusion binding sites in C/G- transduced cells with Polycomb Repressive Complex 2 (PRC2) sites in control cord blood cells identifies MYCN, ZFPM1, ZBTB16 and LMO2 as direct C/G targets. Transcriptomic analysis of a large pediatric AML cohort shows that these genes are upregulated in C/G patient samples. Single cell RNA-sequencing of umbilical cord blood identifies a population of megakaryocyte precursors that already express many of these genes despite lacking the fusion. By integrating CUT&RUN data with CRISPR dependency screens we identify BRG1/SMARCA4 as a vulnerability in C/G AML. BRG1 profiling in C/G patient-derived cell lines shows that the CBFA2T3 locus is a binding site, and treatment with clinically-available BRG1 inhibitors reduces fusion levels and downstream C/G targets including N-MYC, resulting in C/G leukemia cell death and extending survival in a murine xenograft model.
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3
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Le Q, Hadland B, Smith JL, Leonti A, Huang BJ, Ries R, Hylkema TA, Castro S, Tang TT, McKay CN, Perkins L, Pardo L, Sarthy J, Beckman AK, Williams R, Idemmili R, Furlan S, Ishida T, Call L, Srivastava S, Loeb AM, Milano F, Imren S, Morris SM, Pakiam F, Olson JM, Loken MR, Eidenschink Brodersen L, Riddell SR, Tarlock K, Bernstein ID, Loeb KR, Meshinchi S. CBFA2T3-GLIS2 model of pediatric acute megakaryoblastic leukemia identifies FOLR1 as a CAR T cell target. J Clin Invest 2022; 132:157101. [PMID: 36136600 DOI: 10.1172/jci157101] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [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: 01/19/2022] [Accepted: 09/16/2022] [Indexed: 11/17/2022] Open
Abstract
Fusion oncoproteins are the initiating event in the pathogenesis of many pediatric AML. The CBFA2T3-GLIS2 (C/G) fusion is a product of a cryptic translocation primarily seen in infants and early childhood and is associated with dismal outcome. Here, we demonstrate that the expression of the C/G oncogenic fusion protein promotes the transformation of human cord blood hematopoietic stem/progenitor cells (CB HSPCs) in an endothelial cell (EC) co-culture system, that recapitulates the transcriptome, morphology and immunophenotype of C/G AML and induces highly aggressive leukemia in xenograft models. Interrogating the transcriptome of C/G-CB cells and primary C/G AML identified a library of C/G fusion-specific genes that are potential targets for therapy. We developed chimeric antigen receptor (CAR) T cells directed against one of the targets, FOLR1, and demonstrated their pre-clinical efficacy against C/G AML using in vitro and xenograft models. FOLR1 is also expressed in renal and pulmonary epithelium, raising concerns for toxicity that must be addressed for the clinical application of this therapy. Our findings underscore the role of the endothelial niche in promoting leukemic transformation of C/G-transduced CB HSPCs. Furthermore, this work has broad implications for studies of leukemogenesis applicable to a variety of oncogenic fusion-driven pediatric leukemias, providing a robust and tractable model system to characterize the molecular mechanisms of leukemogenesis and identify biomarkers for disease diagnosis and targets for therapy.
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Affiliation(s)
- Quy Le
- Clincial Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Brandon Hadland
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Jenny L Smith
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Amanda Leonti
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Benjamin J Huang
- Department of Pediatrics, University of California, San Francisco, San Francisco, United States of America
| | - Rhonda Ries
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Tiffany A Hylkema
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Sommer Castro
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Thao T Tang
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Cyd N McKay
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - LaKeisha Perkins
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Laura Pardo
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Jay Sarthy
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Amy K Beckman
- Department of Laboratory Medicine and Pathology, The University of Minnesota, Minneapolis, United States of America
| | - Robin Williams
- Department of Laboratory Medicine and Pathology, The University of Minnesota, Minneapolis, United States of America
| | - Rhonda Idemmili
- Department of Laboratory Medicine and Pathology, The University of Minnesota, Minneapolis, United States of America
| | - Scott Furlan
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Takashi Ishida
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Lindsey Call
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Shivani Srivastava
- Program in Immunology, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Anisha M Loeb
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Filippo Milano
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Suzan Imren
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Shelli M Morris
- Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, United States of America
| | - Fiona Pakiam
- Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Insitute, Seattle, United States of America
| | - James M Olson
- Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Insitute, Seattle, United States of America
| | | | | | - Stanley R Riddell
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Katherine Tarlock
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Irwin D Bernstein
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Keith R Loeb
- Department of Pathology, Fred Hutchinson Cancer Research Center, Seattle, United States of America
| | - Soheil Meshinchi
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, United States of America
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4
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Vitanza NA, Biery MC, Myers C, Ferguson E, Zheng Y, Girard EJ, Przystal JM, Park G, Noll A, Pakiam F, Winter CA, Morris SM, Sarthy J, Cole BL, Leary SES, Crane C, Lieberman NAP, Mueller S, Nazarian J, Gottardo R, Brusniak MY, Mhyre AJ, Olson JM. Optimal therapeutic targeting by HDAC inhibition in biopsy-derived treatment-naïve diffuse midline glioma models. Neuro Oncol 2021; 23:376-386. [PMID: 33130903 DOI: 10.1093/neuonc/noaa249] [Citation(s) in RCA: 39] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Diffuse midline gliomas (DMGs), including diffuse intrinsic pontine gliomas (DIPGs), have a dismal prognosis, with less than 2% surviving 5 years postdiagnosis. The majority of DIPGs and all DMGs harbor mutations altering the epigenetic regulatory histone tail (H3 K27M). Investigations addressing DMG epigenetics have identified a few promising drugs, including the HDAC inhibitor (HDACi) panobinostat. Here, we use clinically relevant DMG models to identify and validate other effective HDACi and their biomarkers of response. METHODS HDAC inhibitors were tested across biopsy-derived treatment-naïve in vitro and in vivo DMG models with biologically relevant radiation resistance. RNA sequencing was performed to define and compare drug efficacy and to map predictive biomarkers of response. RESULTS Quisinostat and romidepsin showed efficacy with low nanomolar half-maximal inhibitory concentration (IC50) values (~50 and ~5 nM, respectively). Comparative transcriptome analyses across quisinostat, romidepsin, and panobinostat showed a greater degree of shared biological effects between quisinostat and panobinostat, and less overlap with romidepsin. However, some transcriptional changes were consistent across all 3 drugs at similar biologically effective doses, such as overexpression of troponin T1 slow skeletal type (TNNT1) and downregulation of collagen type 20 alpha 1 chain (COL20A1), identifying these as potential vulnerabilities or on-target biomarkers in DMG. Quisinostat and romidepsin significantly (P < 0.0001) inhibited in vivo tumor growth. CONCLUSIONS Our data highlight the utility of treatment-naïve biopsy-derived models; establishes quisinostat and romidepsin as effective in vivo; illuminates potential mechanisms and/or biomarkers of DMG cell lethality due to HDAC inhibition; and emphasizes the need for brain tumor-penetrant versions of potentially efficacious agents.
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Affiliation(s)
- Nicholas A Vitanza
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Division of Pediatric Hematology/Oncology, Department of Pediatrics, Seattle Children's Hospital, University of Washington, Seattle, Washington, USA
| | - Matt C Biery
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Carrie Myers
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Eric Ferguson
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Ye Zheng
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Emily J Girard
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | | | - Giulia Park
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Alyssa Noll
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Molecular and Cellular Biology Graduate Program and Medical Scientist Training Program, University of Washington, Seattle, Washington, USA
| | - Fiona Pakiam
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Conrad A Winter
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Shelli M Morris
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Jay Sarthy
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Bonnie L Cole
- Department of Laboratories, Seattle Children's Hospital, Seattle, Washington, USA.,Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Sarah E S Leary
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Division of Pediatric Hematology/Oncology, Department of Pediatrics, Seattle Children's Hospital, University of Washington, Seattle, Washington, USA
| | - Courtney Crane
- Ben Towne Center for Childhood Cancer Research, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Nicole A P Lieberman
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, Washington, USA
| | - Sabine Mueller
- University Children's Hospital Zurich, Zurich, Switzerland.,University of California San Francisco, San Francisco, California, USA
| | - Javad Nazarian
- University Children's Hospital Zurich, Zurich, Switzerland.,Department of Genetic Medicine Research, Children's National Medical Center, Washington DC, USA
| | - Raphael Gottardo
- Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Department of Statistics, University of Washington, Seattle, Washington, USA
| | - Mi-Youn Brusniak
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Andrew J Mhyre
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - James M Olson
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA.,Division of Pediatric Hematology/Oncology, Department of Pediatrics, Seattle Children's Hospital, University of Washington, Seattle, Washington, USA
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5
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Biery MC, Noll A, Myers C, Morris SM, Winter CA, Pakiam F, Cole BL, Browd SR, Olson JM, Vitanza NA. A Protocol for the Generation of Treatment-naïve Biopsy-derived Diffuse Intrinsic Pontine Glioma and Diffuse Midline Glioma Models. J Exp Neurol 2020. [PMID: 33768215 PMCID: PMC7990285 DOI: 10.33696//neurol.1.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Diffuse intrinsic pontine glioma (DIPG) is a universally fatal tumor of the brainstem, most commonly affecting young children. Due to its location, surgical resection is not achievable, but consideration of a biopsy has become standard practice at children’s hospitals with the appropriate neurosurgical expertise. While the decision to obtain a biopsy should be directed by the presence of atypical radiographic features that call the diagnosis of DIPG into question or the requirement of biopsy tissue for clinical trial enrollment, once this precious tissue is available its use for research should be considered. The majority of DIPG and diffuse midline glioma, H3 K27M-mutant (DMG) models are autopsy-derived or genetically-engineered, each of which has limitations for translational studies, so the use of biopsy tissue for laboratory model development provides an opportunity to create unique model systems. Here, we present a detailed laboratory protocol for the generation of treatment-naïve biopsy-derived DIPG/DMG models.
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Affiliation(s)
- Matt C Biery
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Alyssa Noll
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Molecular and Cellular Biology Graduate Program and Medical Scientist Training Program, University of Washington, Seattle, WA, USA
| | - Carrie Myers
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | | | - Conrad A Winter
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Department of Laboratories, Seattle Children's Hospital, Seattle, WA, USA
| | - Fiona Pakiam
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Bonnie L Cole
- Department of Laboratories, Seattle Children's Hospital, Seattle, WA, USA.,Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA, USA
| | - Samuel R Browd
- Division of Neurosurgery, Department of Neurological Surgery, University of Washington, Seattle Children's Hospital, Seattle, WA, USA
| | - James M Olson
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Hematology/Oncology, Department of Pediatrics, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
| | - Nicholas A Vitanza
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA.,Division of Hematology/Oncology, Department of Pediatrics, Seattle Children's Hospital, University of Washington, Seattle, WA, USA
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6
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Biery MC, Noll A, Myers C, Morris SM, Winter CA, Pakiam F, Cole BL, Browd SR, Olson JM, Vitanza NA. A Protocol for the Generation of Treatment-naïve Biopsy-derived Diffuse Intrinsic Pontine Glioma and Diffuse Midline Glioma Models. J Exp Neurol 2020; 1:158-167. [PMID: 33768215 PMCID: PMC7990285 DOI: 10.33696/neurol.1.025] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
Abstract
Diffuse intrinsic pontine glioma (DIPG) is a universally fatal tumor of the brainstem, most commonly affecting young children. Due to its location, surgical resection is not achievable, but consideration of a biopsy has become standard practice at children's hospitals with the appropriate neurosurgical expertise. While the decision to obtain a biopsy should be directed by the presence of atypical radiographic features that call the diagnosis of DIPG into question or the requirement of biopsy tissue for clinical trial enrollment, once this precious tissue is available its use for research should be considered. The majority of DIPG and diffuse midline glioma, H3 K27M-mutant (DMG) models are autopsy-derived or genetically-engineered, each of which has limitations for translational studies, so the use of biopsy tissue for laboratory model development provides an opportunity to create unique model systems. Here, we present a detailed laboratory protocol for the generation of treatment-naïve biopsy-derived DIPG/DMG models.
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Affiliation(s)
- Matt C. Biery
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Alyssa Noll
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Molecular and Cellular Biology Graduate Program and Medical Scientist Training Program, University of Washington, Seattle, WA, USA
| | - Carrie Myers
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | | | - Conrad A. Winter
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Department of Laboratories, Seattle Children’s Hospital, Seattle, WA, USA
| | - Fiona Pakiam
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Bonnie L. Cole
- Department of Laboratories, Seattle Children’s Hospital, Seattle, WA, USA
- Department of Laboratory Medicine and Pathology, University of Washington School of Medicine, Seattle, WA, USA
| | - Samuel R. Browd
- Division of Neurosurgery, Department of Neurological Surgery, University of Washington, Seattle Children’s Hospital, Seattle, WA, USA
| | - James M. Olson
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Division of Hematology/Oncology, Department of Pediatrics, Seattle Children’s Hospital, University of Washington, Seattle, WA, USA
| | - Nicholas A. Vitanza
- Fred Hutchinson Cancer Research Center, Seattle, WA, USA
- Division of Hematology/Oncology, Department of Pediatrics, Seattle Children’s Hospital, University of Washington, Seattle, WA, USA
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7
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Morris SM, Mhyre AJ, Carmack SS, Myers CH, Burns C, Ye W, Ferrer M, Olson JM, Klinghoffer RA. A modified gene trap approach for improved high-throughput cancer drug discovery. Oncogene 2018; 37:4226-4238. [PMID: 29717260 PMCID: PMC6076322 DOI: 10.1038/s41388-018-0274-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [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] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Revised: 03/01/2018] [Accepted: 03/23/2018] [Indexed: 01/22/2023]
Abstract
While advances in laboratory automation has dramatically increased throughout of compound screening efforts, development of robust cell-based assays in relevant disease models remain resource-intensive and time-consuming, presenting a bottleneck to drug discovery campaigns. To address this issue, we present a modified gene trap approach to efficiently generate pathway-specific reporters that result in a robust "on" signal when the pathway of interest is inhibited. In this proof-of-concept study, we used vemurafenib and trametinib to identify traps that specifically detect inhibition of the mitogen-activated protein kinase (MAPK) pathway in a model of BRAFV600E driven human malignant melanoma. We demonstrate that insertion of our trap into particular loci results in remarkably specific detection of MAPK pathway inhibitors over compounds targeting any other pathway or cellular function. The accuracy of our approach was highlighted in a pilot screen of ~6000 compounds where 40 actives were detected, including 18 MEK, 10 RAF, and 3 ERK inhibitors along with a few compounds representing previously under-characterized inhibitors of the MAPK pathway. One such compound, bafetinib, a second generation BCR/ABL inhibitor, reduced phosphorylation of ERK and when combined with trametinib, both in vitro and in vivo, reduced growth of vemurafenib resistant melanoma cells. While piloted in a model of BRAF-driven melanoma, our results set the stage for using this approach to rapidly generate reporters against any transcriptionally active pathway across a wide variety of disease-relevant cell-based models to expedite drug discovery efforts.
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Affiliation(s)
- Shelli M Morris
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Andrew J Mhyre
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Savanna S Carmack
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | - Carrie H Myers
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA
| | | | | | | | - James M Olson
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
- Division of Pediatric Hematology/Oncology, University of Washington School of Medicine, Seattle, WA, USA.
- Seattle Children's Hospital, Seattle, WA, USA.
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8
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Morris SM, Mhyre AJ, Carmack SS, Burns C, Ferrer M, Ye W, Olson JM, Klinghoffer RA. Abstract 4023: The SABRE platform: A novel, unbiased technology for drug discovery and prioritization. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-4023] [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
Targeted therapies designed to inhibit hyperactive oncogenic signaling have demonstrated some encouraging clinical responses. However, most of the time these responses are not durable as tumors “work around” pathway inhibition, often reactivating the inhibited pathway, leading to drug resistance and disease relapse. New technologies that enable more efficient discovery and development of “suites” of drugs that comprehensively inhibit multiple pathway nodes are needed. The SABRE (Splice Acceptor Brilliant Reporter) platform was developed to provide an unbiased method to screen large compound libraries and dramatically improve the speed and efficiency of which novel targeted therapeutics can be identified. SABRE is built off the premise that oncogenic output is exerted through changes in gene transcription and that such changes can be harnessed as powerful reporters of pathway activation status. SABRE utilizes the power of gene trap technology coupled with a drug selection process to isolate cells that generate a robust “off to on” signal in response to target or pathway inhibition. Via massively parallel comparative analysis, multiple traps let nature provide the best reporter for further analysis and drug discovery. In this proof-of-concept study, we employed the SABRE technology to identify insertion sites that are specifically regulated by the MAPK pathway. Experiments were performed using the human BRAFV600E mutant melanoma cell line A375. SABRE lentiviral transduced A375 cells were treated with trametinib, a MEK inhibitor, and clones were isolated that emitted a positive luciferase signal upon drug treatment. To determine if these reporters were MAPK pathway specific, the platform was miniaturized to a 1536 well format and used to screen a 6000+ compound library. Results from the screen found that 70% (28/40) of the top drug hits were known to directly modulate the MAPK pathway. Since drug resistance is a common occurrence in melanoma, we generated a “resistant” A375 SABRE reporter line to increasing concentrations of vemurafenib and interrogated the top drug candidates identified in the screen. As expected, the resistant SABRE line failed to respond to BRAFV600E specific inhibitors but continued to respond to downstream MEK inhibitors, which is helping to delineate the mechanism of resistance. We were also interested in the screening hits that were not previously known to influence the MAPK pathway including bafetinib and a Tie2 inhibitor. In follow-up testing, we found that these drugs induced robust and titratable reporter signals in both the SABRE A375 vemurafenib sensitive and resistant lines. In addition, treatment of either bafetinib or the Tie2 inhibitor reduced ERK phosphorylation in the vemurafenib resistant cells, suggesting that these drugs could be useful in the treatment of drug resistant melanomas. Studies are currently underway to determine the in vivo efficacy of these drugs in A375 SABRE reporter xenograft models.
Citation Format: Shelli M. Morris, Andrew J. Mhyre, Savanna S. Carmack, Connor Burns, Marc Ferrer, Wenjuan Ye, James M. Olson, Richard A. Klinghoffer. The SABRE platform: A novel, unbiased technology for drug discovery and prioritization [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4023. doi:10.1158/1538-7445.AM2017-4023
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9
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Mhyre AJ, Turnbaugh S, Morris SM, Xin H, Paddison PJ, Ferrer M, Olson JM. Abstract 3200: Targeting PHF5A for the treatment of glioblastoma and other Myc-driven cancers. Cancer Res 2017. [DOI: 10.1158/1538-7445.am2017-3200] [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
Glioblastoma multiforme (GBM) is one of the most aggressive and invasive types of brain cancer, but targeted treatment options remain elusive. The standard of care (surgery chemotherapy and radiation) falls far short of where it should be with two-year survival rates less than 10%. Using stem cell isolates from GBM patients, we found that perturbing PHF5A, a component of the spliceosome machinery, was lethal and caused hundreds of genes to be mis-spliced. These mis-splicing events included both exon skipping and intron inclusions. In contrast, similar levels of PHF5A suppression in normal control stem cells and astrocytes failed to induce cell death and mis-splicing, indicating that PHF5A plays a specific role in the cancer biology. Moreover, when normal astrocytes were transformed with the Myc oncogene, they became sensitive to PHF5A perturbation. Taken together, these results suggested that specifically inhibiting PHF5A would be an effective therapy for glioblastoma and other Myc-driven cancers. Specifically targeting PHF5A would also likely result in reduced side-effects seen with general spliceosome inhibitors. Unfortunately, there are currently no known inhibitors that target PHF5A.
In order to discovery novel PHF5A inhibitors, we created a mini-gene mis-splicing reporter assay that was sensitive to both general spliceosome inhibitors and PHF5A perturbation. In a 96-well assay format, the assay was robust with a 200-fold assay window and Z’ values over 0.8. Following miniaturization to a 1536-well format, we conducted a high throughput screening (HTS) campaign testing 450,000 small molecule compounds. The initial hits were retested and counter-screened yielding 381 confirmed actives and we are further interrogating these actives in secondary and tertiary assays. Future efforts will focus on developing an SAR of the lead and backup series and identifying potential liabilities that will be addressed, if necessary, in further lead optimization efforts. We are enthusiastic about the potential of developing a targeted PHF5A inhibitor as a novel and effective therapy for patients and their families fighting GBM and other Myc-driven cancers.
Citation Format: Andrew J. Mhyre, Shanon Turnbaugh, Shelli M. Morris, Hu Xin, Patrick J. Paddison, Marc Ferrer, James M. Olson. Targeting PHF5A for the treatment of glioblastoma and other Myc-driven cancers [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3200. doi:10.1158/1538-7445.AM2017-3200
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Affiliation(s)
| | | | | | - Hu Xin
- 2National Institutes of Health, Bethesda, MD
| | | | - Marc Ferrer
- 2National Institutes of Health, Bethesda, MD
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10
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Morris SM, Davison J, Carter KT, O'Leary RM, Trobridge P, Knoblaugh SE, Myeroff LL, Markowitz SD, Brett BT, Scheetz TE, Dupuy AJ, Starr TK, Grady WM. Transposon mutagenesis identifies candidate genes that cooperate with loss of transforming growth factor-beta signaling in mouse intestinal neoplasms. Int J Cancer 2016; 140:853-863. [PMID: 27790711 DOI: 10.1002/ijc.30491] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2016] [Revised: 10/06/2016] [Accepted: 10/10/2016] [Indexed: 12/22/2022]
Abstract
Colorectal cancer (CRC) results from the accumulation of gene mutations and epigenetic alterations in colon epithelial cells, which promotes CRC formation through deregulating signaling pathways. One of the most commonly deregulated signaling pathways in CRC is the transforming growth factor β (TGF-β) pathway. Importantly, the effects of TGF-β signaling inactivation in CRC are modified by concurrent mutations in the tumor cell, and these concurrent mutations determine the ultimate biological effects of impaired TGF-β signaling in the tumor. However, many of the mutations that cooperate with the deregulated TGF-β signaling pathway in CRC remain unknown. Therefore, we sought to identify candidate driver genes that promote the formation of CRC in the setting of TGF-β signaling inactivation. We performed a forward genetic screen in mice carrying conditionally inactivated alleles of the TGF-β receptor, type II (Tgfbr2) using Sleeping Beauty (SB) transposon mediated mutagenesis. We used TAPDANCE and Gene-centric statistical methods to identify common insertion sites (CIS) and, thus, candidate tumor suppressor genes and oncogenes within the tumor genome. CIS analysis of multiple neoplasms from these mice identified many candidate Tgfbr2 cooperating genes and the Wnt/β-catenin, Hippo and MAPK pathways as the most commonly affected pathways. Importantly, the majority of candidate genes were also found to be mutated in human CRC. The SB transposon system provides an unbiased method to identify Tgfbr2 cooperating genes in mouse CRC that are functionally relevant and that may provide further insight into the pathogenesis of human CRC.
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Affiliation(s)
- Shelli M Morris
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Jerry Davison
- Public Health Sciences Division, Genomics and Bioinformatics Shared Resource, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Kelly T Carter
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Rachele M O'Leary
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Patty Trobridge
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Sue E Knoblaugh
- Department of Veterinary Biosciences, The Ohio State University, Columbus, OH
| | - Lois L Myeroff
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH
- Department of Medicine, Case Western Reserve University, Cleveland, OH
| | - Sanford D Markowitz
- Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH
- Department of Medicine, Case Western Reserve University, Cleveland, OH
- Department of Genetics and Genome Sciences, Case Western Reserve University, Cleveland, OH
| | - Benjamin T Brett
- Center for Bioinformatics and Computational Biology, University of Iowa, Iowa City, IA
| | - Todd E Scheetz
- Center for Bioinformatics and Computational Biology, University of Iowa, Iowa City, IA
- Department of Ophthalmology and Visual Sciences, Roy J. & Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Adam J Dupuy
- Department of Anatomy and Cell Biology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA
- Department of Pathology, Roy J. and Lucille A. Carver College of Medicine, University of Iowa, Iowa City, IA
| | - Timothy K Starr
- Department of Obstetrics, Gynecology & Women's Health, Masonic Cancer Center, University of Minnesota, Minneapolis, MN
- Department of Genetics, Cell Biology & Development, University of Minnesota, Minneapolis, MN
| | - William M Grady
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
- Department of Medicine, University of Washington School of Medicine, Seattle, WA
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11
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Klinghoffer RA, Bahrami SB, Hatton BA, Frazier JP, Moreno-Gonzalez A, Strand AD, Kerwin WS, Casalini JR, Thirstrup DJ, You S, Morris SM, Watts KL, Veiseh M, Grenley MO, Tretyak I, Dey J, Carleton M, Beirne E, Pedro KD, Ditzler SH, Girard EJ, Deckwerth TL, Bertout JA, Meleo KA, Filvaroff EH, Chopra R, Press OW, Olson JM. A technology platform to assess multiple cancer agents simultaneously within a patient's tumor. Sci Transl Med 2016; 7:284ra58. [PMID: 25904742 DOI: 10.1126/scitranslmed.aaa7489] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
A fundamental problem in cancer drug development is that antitumor efficacy in preclinical cancer models does not translate faithfully to patient outcomes. Much of early cancer drug discovery is performed under in vitro conditions in cell-based models that poorly represent actual malignancies. To address this inconsistency, we have developed a technology platform called CIVO, which enables simultaneous assessment of up to eight drugs or drug combinations within a single solid tumor in vivo. The platform is currently designed for use in animal models of cancer and patients with superficial tumors but can be modified for investigation of deeper-seated malignancies. In xenograft lymphoma models, CIVO microinjection of well-characterized anticancer agents (vincristine, doxorubicin, mafosfamide, and prednisolone) induced spatially defined cellular changes around sites of drug exposure, specific to the known mechanisms of action of each drug. The observed localized responses predicted responses to systemically delivered drugs in animals. In pair-matched lymphoma models, CIVO correctly demonstrated tumor resistance to doxorubicin and vincristine and an unexpected enhanced sensitivity to mafosfamide in multidrug-resistant lymphomas compared with chemotherapy-naïve lymphomas. A CIVO-enabled in vivo screen of 97 approved oncology agents revealed a novel mTOR (mammalian target of rapamycin) pathway inhibitor that exhibits significantly increased tumor-killing activity in the drug-resistant setting compared with chemotherapy-naïve tumors. Finally, feasibility studies to assess the use of CIVO in human and canine patients demonstrated that microinjection of drugs is toxicity-sparing while inducing robust, easily tracked, drug-specific responses in autochthonous tumors, setting the stage for further application of this technology in clinical trials.
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Affiliation(s)
| | - S Bahram Bahrami
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | | | | | | | - Andrew D Strand
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | | | | | | | - Sheng You
- Presage Biosciences, Seattle, WA 98109, USA
| | | | | | - Mandana Veiseh
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | | | | | - Joyoti Dey
- Presage Biosciences, Seattle, WA 98109, USA
| | | | | | - Kyle D Pedro
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | | | - Emily J Girard
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | | | | | - Karri A Meleo
- Oncology Department, BluePearl Veterinary Partners, Seattle, WA 98125, USA
| | | | | | - Oliver W Press
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - James M Olson
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.,Department of Pediatrics, University of Washington, Seattle, WA 98195, USA.,Seattle Children's Hospital, Seattle, WA 98105, USA
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Yu M, O'Leary RM, Kaz AM, Morris SM, Carter KT, Chak A, Chandar A, Willis JE, Moinova HR, Markowitz SD, Brenner DE, Anandabapasathy S, Westerhoff M, Wong CJ, Shaheen NJ, Chen Y, Barnholtz-Sloan JS, Grady WM. Methylated B3GAT2 and ZNF793 Are Potential Detection Biomarkers for Barrett's Esophagus. Cancer Epidemiol Biomarkers Prev 2015; 24:1890-7. [PMID: 26545406 DOI: 10.1158/1055-9965.epi-15-0370] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Accepted: 09/30/2015] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Barrett's esophagus (BE) is a preneoplastic condition in which normal esophageal squamous epithelium (SQ) is replaced by specialized intestinal metaplasia. It is the presumed precursor for esophageal adenocarcinoma (EAC) as well as the strongest risk factor for this cancer. Unfortunately, many patients with BE go undiagnosed under the current BE screening guidelines. The development of noninvasive and accurate BE detection assays could potentially identify many of these undiagnosed BE patients. METHODS DNA methylation is a common epigenetic alteration in BE. Therefore, we conducted a genome-wide methylation screen to identify potential BE biomarkers. Samples from SQ (N = 12), stomach (N = 28), and BE (N = 29) were analyzed and methylation levels at over 485,000 CpG sites were compared. Pyrosequencing assays were used to validate the results and MethyLight assays were developed to detect the methylated alleles in endoscopic brushings. RESULTS We discovered two genes, B3GAT2 and ZNF793, that are aberrantly methylated in BE. Clinical validation studies confirmed B3GAT2 and ZNF793 methylation levels were significantly higher in BE samples (median = 32.5% and 33.1%, respectively) than in control tissues (median = 2.29% and 2.52%, respectively; P < 0.0001 for both genes). Furthermore, gene-specific MethyLight assays could accurately detect BE (P < 0.0001 for both) in endoscopic brushing samples. CONCLUSION B3GAT2 and ZNF793 are hypermethylated in BE, and the methylation status of these genes can be used to detect BE in tissue samples. IMPACT These findings support the development of methylated B3GAT2 and ZNF793 as biomarkers for noninvasive assays for the detection of BE.
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Affiliation(s)
- Ming Yu
- Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Rachele M O'Leary
- Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Andrew M Kaz
- Research and Development Service, VA Puget Sound Health Care System, Seattle, Washington. Department of Medicine, University of Washington School of Medicine, Seattle, Washington
| | - Shelli M Morris
- Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Kelly T Carter
- Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Amitabh Chak
- Division of Gastroenterology, University Hospitals Case Medical Center, Cleveland, Ohio. Division of Oncology, University Hospitals Case Medical Center, Cleveland, Ohio
| | - Apoorva Chandar
- Division of Gastroenterology, University Hospitals Case Medical Center, Cleveland, Ohio. Division of Oncology, University Hospitals Case Medical Center, Cleveland, Ohio
| | - Joseph E Willis
- Department of Pathology, University Hospitals Case Medical Center, Cleveland, Ohio
| | - Helen R Moinova
- Department of Medicine, University Hospitals Case Medical Center, Cleveland, Ohio
| | - Sanford D Markowitz
- Department of Medicine, University Hospitals Case Medical Center, Cleveland, Ohio. Case Comprehensive Cancer Center, Case Western Reserve University, School of Medicine, Cleveland, Ohio
| | - Dean E Brenner
- University of Michigan Medical Center, Ann Arbor, Michigan
| | | | - Maria Westerhoff
- Department of Anatomic Pathology, University of Washington School of Medicine, Seattle, Washington
| | - Chao-Jen Wong
- Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Nicholas J Shaheen
- Division of Gastroenterology & Hepatology, University of North Carolina Hospitals, Chapel Hill, North Carolina
| | - Yanwen Chen
- Case Comprehensive Cancer Center, Case Western Reserve University, School of Medicine, Cleveland, Ohio
| | - Jill S Barnholtz-Sloan
- Case Comprehensive Cancer Center, Case Western Reserve University, School of Medicine, Cleveland, Ohio
| | - William M Grady
- Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, Washington. Department of Medicine, University of Washington School of Medicine, Seattle, Washington.
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13
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Varma SD, Devamanoharan PS, Morris SM. Oxygen and light as risk factors in senile cataract development: experimental studies. Dev Ophthalmol 2015; 21:162-9. [PMID: 1868942 DOI: 10.1159/000419952] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- S D Varma
- Department of Ophthalmology, University of Maryland School of Medicine, Baltimore
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Stockdale RM, Kaz AM, Morris SM, Chak A, Willis J, Brenner D, Anandabapasathy S, Westerhoff M, Wong CJ, Barnholtz-Sloan J, Chen Y, Grady WM. Abstract 2292: Epigenetic alterations in Barrett's esophagus and esophageal adenocarcinoma: identification and evaluation of potential biomarkers. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-2292] [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
Patients diagnosed with esophageal adenocarcinoma (EAC) have poor long-term survival rates. Currently, patients identified with Barrett's esophagus (BE), the strongest risk factor for EAC, are placed in costly and invasive surveillance programs. The impact of these surveillance programs on decreasing EAC related mortality is debatable, presumably because many patients with BE are not diagnosed until they develop cancer and because of suboptimal BE risk markers for EAC. Thus, there is a need for more accurate biomarkers. Epigenetic alterations in BE have the potential to be detection and risk markers for BE and EAC. In order to identify individual gene methylation patterns of normal squamous (SQ) epithelium, BE, low-grade dysplasia, high-grade dysplasia and EAC tissues, we have conducted genome-wide methylation assessments of these tissue types using HumanMethylation450 arrays (Illumina). Unique methylation signatures for each histological subtype have been identified by unsupervised clustering. Additionally, we determined the mean methylation state (‘beta value’) for more than 480,000 CpGs for each sample group. After normalization and filtering, differentially methylated loci (FDR p < 0.05) with mean beta values with differences greater than 0.20 between the different tissue types were used to identify potential biomarkers. These biomarkers were then subjected to technical and clinical validation studies. We have currently identified and validated four potential biomarkers that may be useful in detection assays for BE and EAC. We have found two CpGs that distinguish EAC from BE, and two other CpGs that distinguish BE from SQ epithelium. The best performing biomarker has 100% sensitivity and 87.5% specificity in its ability to distinguish BE from EAC in the validation set of tissue samples. We presently have a number of additional candidates in various stages of validation. In summary, we have shown that differential methylation patterns exist between the various stages of progression from normal SQ epithelium to BE and ultimately EAC. Furthermore, some of these methylated CpGs have potential to be used as detection markers for BE or EAC.
Citation Format: Rachele M. Stockdale, Andrew M. Kaz, Shelli M. Morris, Amitabh Chak, Joseph Willis, Dean Brenner, Sharmila Anandabapasathy, Maria Westerhoff, Chao-Jen Wong, Jill Barnholtz-Sloan, Yanwen Chen, William M. Grady. Epigenetic alterations in Barrett's esophagus and esophageal adenocarcinoma: identification and evaluation of potential biomarkers. [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 2292. doi:10.1158/1538-7445.AM2014-2292
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Affiliation(s)
| | - Andrew M. Kaz
- 1Fred Hutchinson Cancer Research Center, Seattle, WA
| | | | | | | | | | | | | | - Chao-Jen Wong
- 1Fred Hutchinson Cancer Research Center, Seattle, WA
| | | | - Yanwen Chen
- 2Case Western Reserve University, Cleveland, OH
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15
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Luo Y, Wong CJ, Kaz AM, Dzieciatkowski S, Carter KT, Morris SM, Wang J, Willis JE, Makar KW, Ulrich CM, Lutterbaugh JD, Shrubsole MJ, Zheng W, Markowitz SD, Grady WM. Differences in DNA methylation signatures reveal multiple pathways of progression from adenoma to colorectal cancer. Gastroenterology 2014; 147:418-29.e8. [PMID: 24793120 PMCID: PMC4107146 DOI: 10.1053/j.gastro.2014.04.039] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/06/2013] [Revised: 04/15/2014] [Accepted: 04/23/2014] [Indexed: 12/16/2022]
Abstract
BACKGROUND & AIMS Genetic and epigenetic alterations contribute to the pathogenesis of colorectal cancer (CRC). There is considerable molecular heterogeneity among colorectal tumors, which appears to arise as polyps progress to cancer. This heterogeneity results in different pathways to tumorigenesis. Although epigenetic and genetic alterations have been detected in conventional tubular adenomas, little is known about how these affect progression to CRC. We compared methylomes of normal colon mucosa, tubular adenomas, and colorectal cancers to determine how epigenetic alterations might contribute to cancer formation. METHODS We conducted genome-wide array-based studies and comprehensive data analyses of aberrantly methylated loci in 41 normal colon tissue, 42 colon adenomas, and 64 cancers using HumanMethylation450 arrays. RESULTS We found genome-wide alterations in DNA methylation in the nontumor colon mucosa and cancers. Three classes of cancers and 2 classes of adenomas were identified based on their DNA methylation patterns. The adenomas separated into classes of high-frequency methylation and low-frequency methylation. Within the high-frequency methylation adenoma class a subset of adenomas had mutant KRAS. Additionally, the high-frequency methylation adenoma class had DNA methylation signatures similar to those of cancers with low or intermediate levels of methylation, and the low-frequency methylation adenoma class had methylation signatures similar to that of nontumor colon tissue. The CpG sites that were differentially methylated in these signatures are located in intragenic and intergenic regions. CONCLUSIONS Genome-wide alterations in DNA methylation occur during early stages of progression of tubular adenomas to cancer. These findings reveal heterogeneity in the pathogenesis of colorectal cancer, even at the adenoma step of the process.
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Affiliation(s)
- Yanxin Luo
- Department of Colorectal Surgery, The Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, PR China; Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington.
| | - Chao-Jen Wong
- Clinical Research Division, Fred Hutchinson Cancer Research
Center, Seattle, WA, USA
| | - Andrew M. Kaz
- Clinical Research Division, Fred Hutchinson Cancer Research
Center, Seattle, WA, USA,Research and Development Service, VA Puget Sound Health
Care System, Seattle, WA, USA,Department of Medicine, University of Washington School of
Medicine, Seattle, WA, USA
| | | | - Kelly T. Carter
- Clinical Research Division, Fred Hutchinson Cancer Research
Center, Seattle, WA, USA
| | - Shelli M. Morris
- Clinical Research Division, Fred Hutchinson Cancer Research
Center, Seattle, WA, USA
| | - Jianping Wang
- Department of Colorectal Surgery, The Sixth Affiliated
Hospital, Sun Yat-Sen University, Guangzhou, P.R. China
| | - Joseph E. Willis
- Department of Pathology, Case Medical Center, Case
Comprehensive Cancer Center and Case Western Reserve University, Cleveland, OH,
USA
| | - Karen W. Makar
- Public Health Sciences Division, Fred Hutchinson Cancer
Research Center, Seattle, WA, USA
| | - Cornelia M. Ulrich
- Public Health Sciences Division, Fred Hutchinson Cancer
Research Center, Seattle, WA, USA,National Center for Tumor Diseases (NCT) and German Cancer
Research Center (DKFZ), University of Heidelberg, Heidelberg, Germany GDR
| | - James D. Lutterbaugh
- Department of Medicine and Ireland Cancer Center, Case
Western Reserve University School of Medicine and Case Medical Center, Cleveland,
OH, USA
| | - Martha J. Shrubsole
- Division of Epidemiology, Department of Medicine,
Vanderbilt Epidemiology Center, Vanderbilt University School of Medicine, Nashville,
TN, USA
| | - Wei Zheng
- Division of Epidemiology, Department of Medicine,
Vanderbilt Epidemiology Center, Vanderbilt University School of Medicine, Nashville,
TN, USA
| | - Sanford D. Markowitz
- Department of Medicine and Ireland Cancer Center, Case
Western Reserve University School of Medicine and Case Medical Center, Cleveland,
OH, USA
| | - William M. Grady
- Clinical Research Division, Fred Hutchinson Cancer Research
Center, Seattle, WA, USA
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Castles F, Morris SM, Hung JMC, Qasim MM, Wright AD, Nosheen S, Choi SS, Outram BI, Elston SJ, Burgess C, Hill L, Wilkinson TD, Coles HJ. Stretchable liquid-crystal blue-phase gels. Nat Mater 2014; 13:817-21. [PMID: 24880732 DOI: 10.1038/nmat3993] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2014] [Accepted: 04/25/2014] [Indexed: 05/24/2023]
Abstract
Liquid-crystalline polymers are materials of considerable scientific interest and technological value. An important subset of these materials exhibit rubber-like elasticity, combining the optical properties of liquid crystals with the mechanical properties of rubber. Moreover, they exhibit behaviour not seen in either type of material independently, and many of their properties depend crucially on the particular mesophase employed. Such stretchable liquid-crystalline polymers have previously been demonstrated in the nematic, chiral-nematic, and smectic mesophases. Here, we report the fabrication of a stretchable gel of blue phase I, which forms a self-assembled, three-dimensional photonic crystal that remains electro-optically switchable under a moderate applied voltage, and whose optical properties can be manipulated by an applied strain. We also find that, unlike its undistorted counterpart, a mechanically deformed blue phase exhibits a Pockels electro-optic effect, which sets out new theoretical challenges and possibilities for low-voltage electro-optic devices.
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Affiliation(s)
- F Castles
- 1] Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK [2] Department of Materials, University of Oxford, Parks Road Oxford OX1 3PH, UK
| | - S M Morris
- 1] Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK [2] Department of Engineering Science, University of Oxford, Parks Road Oxford OX1 3PJ, UK
| | - J M C Hung
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK
| | - M M Qasim
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK
| | - A D Wright
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK
| | - S Nosheen
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK
| | - S S Choi
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK
| | - B I Outram
- Department of Engineering Science, University of Oxford, Parks Road Oxford OX1 3PJ, UK
| | - S J Elston
- Department of Engineering Science, University of Oxford, Parks Road Oxford OX1 3PJ, UK
| | - C Burgess
- Defence Science & Technology Laboratory, Porton Down Salisbury SP4 0JQ, UK
| | - L Hill
- Defence Science & Technology Laboratory, Porton Down Salisbury SP4 0JQ, UK
| | - T D Wilkinson
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK
| | - H J Coles
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue Cambridge CB3 0FA, UK
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Yu M, Trobridge P, Wang Y, Kanngurn S, Morris SM, Knoblaugh S, Grady WM. Inactivation of TGF-β signaling and loss of PTEN cooperate to induce colon cancer in vivo. Oncogene 2014; 33:1538-47. [PMID: 23604118 PMCID: PMC3883899 DOI: 10.1038/onc.2013.102] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2012] [Revised: 01/18/2013] [Accepted: 02/01/2013] [Indexed: 12/12/2022]
Abstract
The accumulation of genetic and epigenetic alterations mediates colorectal cancer (CRC) formation by deregulating key signaling pathways in cancer cells. In CRC, one of the most commonly inactivated signaling pathways is the transforming growth factor-beta (TGF-β) signaling pathway, which is often inactivated by mutations of TGF-β type II receptor (TGFBR2). Another commonly deregulated pathway in CRC is the phosphoinositide-3-kinase (PI3K)-AKT pathway. Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is an important negative regulator of PI3K-AKT signaling and is silenced in ∼30% of CRC. The combination of TGFBR2 inactivation and loss of PTEN is particularly common in microsatellite-unstable CRCs. Consequently, we determined in vivo if deregulation of these two pathways cooperates to affect CRC formation by analyzing tumors arising in mice that lack Tgfbr2 and/or Pten specifically in the intestinal epithelium. We found that lack of Tgfbr2 (Tgfbr2(IEKO)) alone is not sufficient for intestinal tumor formation and lack of Pten (Pten(IEKO)) alone had a weak effect on intestinal tumor induction. However, the combination of Tgfbr2 inactivation with Pten loss (Pten(IEKO);Tgfbr2(IEKO)) led to malignant tumors in both the small intestine and colon in 86% of the mice and to metastases in 8% of the tumor-bearing mice. Moreover, these tumors arose via a β-catenin-independent mechanism. Inactivation of TGF-β signaling and loss of Pten in the tumors led to increased cell proliferation, decreased apoptosis and decreased expression of cyclin-dependent kinase inhibitors. Thus, inactivation of TGF-β signaling and loss of PTEN cooperate to drive intestinal cancer formation and progression by suppressing cell cycle inhibitors.
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Affiliation(s)
- Ming Yu
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | | | - Yuxin Wang
- Department of Microbiology, University of Washington, Seattle, WA
- Department of Medicine, University of Washington, Medical School, Seattle, WA
| | - Samornmas Kanngurn
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
- Department of Pathology, Prince of Songkla University, Hatyai, Thailand
| | - Shelli M. Morris
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - Sue Knoblaugh
- Comparative Medicine, Fred Hutchinson Cancer Research Center, Seattle, WA
| | - William M. Grady
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA
- Department of Medicine, University of Washington, Medical School, Seattle, WA
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Luo Y, Kaz AM, Kanngurn S, Welsch P, Morris SM, Wang J, Lutterbaugh JD, Markowitz SD, Grady WM. NTRK3 is a potential tumor suppressor gene commonly inactivated by epigenetic mechanisms in colorectal cancer. PLoS Genet 2013; 9:e1003552. [PMID: 23874207 PMCID: PMC3708790 DOI: 10.1371/journal.pgen.1003552] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2012] [Accepted: 04/23/2013] [Indexed: 12/03/2022] Open
Abstract
NTRK3 is a member of the neurotrophin receptor family and regulates cell survival. It appears to be a dependence receptor, and thus has the potential to act as an oncogene or as a tumor suppressor gene. NTRK3 is a receptor for NT-3 and when bound to NT-3 it induces cell survival, but when NT-3 free, it induces apoptosis. We identified aberrantly methylated NTRK3 in colorectal cancers through a genome-wide screen for hypermethylated genes. This discovery led us to assess whether NTRK3 could be a tumor suppressor gene in the colon. NTRK3 is methylated in 60% of colon adenomas and 67% of colon adenocarcinomas. NTRK3 methylation suppresses NTRK3 expression. Reconstitution of NTRK3 induces apoptosis in colorectal cancers, if NT-3 is absent. Furthermore, the loss of NTRK3 expression associates with neoplastic transformation in vitro and in vivo. We also found that a naturally occurring mutant NTRK3 found in human colorectal cancer inhibits the tumor suppressor activity of NTRK3. In summary, our findings suggest NTRK3 is a conditional tumor suppressor gene that is commonly inactivated in colorectal cancer by both epigenetic and genetic mechanisms whose function in the pathogenesis of colorectal cancer depends on the expression status of its ligand, NT-3. NTRK3 is a neurotrophin receptor and appears to be a dependence receptor in certain tissues. NTRK3 has been previously shown to be an oncogene in breast cancer and possibly hepatocellular carcinoma. Through a genome-wide methylation screen, we unexpectedly found that NTRK3 is commonly methylated in colorectal cancers but not in normal colon samples, which led us to assess whether NTRK3 could be a tumor suppressor gene in the colon. We now demonstrate that NTRK3 is frequently methylated in colorectal adenomas and cancers. Induced NTRK3 expression in the absence of its ligand, NT-3, causes apoptosis and suppresses in vitro anchorage-independent colony formation and in vivo tumor growth. Reintroduction of NT-3 releases colon cancer cells from NTRK3-mediated apoptosis, which is consistent with NTRK3 being a dependence receptor in the colon. Finally, somatic mutations of NTRK3 have been observed in primary human colorectal cancer. We provide evidence that a subset of these mutations inactivate tumor suppressor activities of NTRK3. These findings suggest that NTRK3 is a conditional tumor suppressor gene in the colon that is inactivated by both genetic and epigenetic mechanisms and whose function in the pathogenesis of colorectal cancer depends on the expression status of its ligand, NT-3.
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Affiliation(s)
- Yanxin Luo
- Department of Colorectal Surgery, The Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, P.R. China
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Andrew M. Kaz
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Research and Development Service, VA Puget Sound Health Care System, Seattle, Washington, United States of America
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
| | - Samornmas Kanngurn
- Tumor Biology Research Unit and Department of Pathology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Piri Welsch
- Division of Medical Genetics, University of Washington Medical School, Seattle, Washington, United States of America
| | - Shelli M. Morris
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
| | - Jianping Wang
- Department of Colorectal Surgery, The Sixth Affiliated Hospital, Sun Yat-Sen University, Guangzhou, P.R. China
| | - James D. Lutterbaugh
- Department of Medicine and Ireland Cancer Center, Case Western Reserve University School of Medicine and Case Medical Center, Cleveland, Ohio, United States of America
| | - Sanford D. Markowitz
- Department of Medicine and Ireland Cancer Center, Case Western Reserve University School of Medicine and Case Medical Center, Cleveland, Ohio, United States of America
| | - William M. Grady
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington, United States of America
- Department of Medicine, University of Washington School of Medicine, Seattle, Washington, United States of America
- * E-mail:
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Mavrogordatos TK, Morris SM, Wood SM, Coles HJ, Wilkinson TD. Spontaneous emission from radiative chiral nematic liquid crystals at the photonic band-gap edge: an investigation into the role of the density of photon states near resonance. Phys Rev E Stat Nonlin Soft Matter Phys 2013; 87:062504. [PMID: 23848702 DOI: 10.1103/physreve.87.062504] [Citation(s) in RCA: 1] [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: 03/08/2013] [Indexed: 06/02/2023]
Abstract
In this article, we investigate the spontaneous emission properties of radiating molecules embedded in a chiral nematic liquid crystal, under the assumption that the electronic transition frequency is close to the photonic edge mode of the structure, i.e., at resonance. We take into account the transition broadening and the decay of electromagnetic field modes supported by the so-called "mirrorless"cavity. We employ the Jaynes-Cummings Hamiltonian to describe the electron interaction with the electromagnetic field, focusing on the mode with the diffracting polarization in the chiral nematic layer. As known in these structures, the density of photon states, calculated via the Wigner method, has distinct peaks on either side of the photonic band gap, which manifests itself as a considerable modification of the emission spectrum. We demonstrate that, near resonance, there are notable differences between the behavior of the density of states and the spontaneous emission profile of these structures. In addition, we examine in some detail the case of the logarithmic peak exhibited in the density of states in two-dimensional photonic structures and obtain analytic relations for the Lamb shift and the broadening of the atomic transition in the emission spectrum. The dynamical behavior of the atom-field system is described by a system of two first-order differential equations, solved using the Green's-function method and the Fourier transform. The emission spectra are then calculated and compared with experimental data.
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Affiliation(s)
- Th K Mavrogordatos
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom.
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Mavrogordatos TK, Morris SM, Castles F, Hands PJW, Ford AD, Coles HJ, Wilkinson TD. Density of photon states in dye-doped chiral nematic liquid crystal cells in the presence of losses and gain. Phys Rev E Stat Nonlin Soft Matter Phys 2012; 86:011705. [PMID: 23005435 DOI: 10.1103/physreve.86.011705] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Indexed: 06/01/2023]
Abstract
We calculate the density of photon states (DOS) of the normal modes in dye-doped chiral nematic liquid crystal (LC) cells in the presence of various loss mechanisms. Losses and gain are incorporated into the transmission characteristics through the introduction of a small imaginary part in the dielectric constant perpendicular and along the director, for which we assume no frequency dispersion. Theoretical results are presented on the DOS in the region of the photonic band gap for a range of values of the loss coefficient and different values of the optical anisotropy. The obtained values of the DOS at the photonic band gap edges predict a reversal of the dominant modes in the structure. Our results are found to be in good agreement with the experimentally obtained excitation thresholds in chiral nematic LC lasers. The behavior of the DOS is also discussed for amplifying LC cells providing additional insight to the lasing mechanism of these structures.
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Affiliation(s)
- Th K Mavrogordatos
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
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Castles F, Day FV, Morris SM, Ko DH, Gardiner DJ, Qasim MM, Nosheen S, Hands PJW, Choi SS, Friend RH, Coles HJ. Blue-phase templated fabrication of three-dimensional nanostructures for photonic applications. Nat Mater 2012; 11:599-603. [PMID: 22581313 DOI: 10.1038/nmat3330] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Accepted: 04/10/2012] [Indexed: 05/31/2023]
Abstract
A promising approach to the fabrication of materials with nanoscale features is the transfer of liquid-crystalline structure to polymers. However, this has not been achieved in systems with full three-dimensional periodicity. Here we demonstrate the fabrication of self-assembled three-dimensional nanostructures by polymer templating blue phase I, a chiral liquid crystal with cubic symmetry. Blue phase I was photopolymerized and the remaining liquid crystal removed to create a porous free-standing cast, which retains the chiral three-dimensional structure of the blue phase, yet contains no chiral additive molecules. The cast may in turn be used as a hard template for the fabrication of new materials. By refilling the cast with an achiral nematic liquid crystal, we created templated blue phases that have unprecedented thermal stability in the range -125 to 125 °C, and that act as both mirrorless lasers and switchable electro-optic devices. Blue-phase templated materials will facilitate advances in device architectures for photonics applications in particular.
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Affiliation(s)
- F Castles
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, UK
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Morris SM, Baek JY, Koszarek A, Kanngurn S, Knoblaugh SE, Grady WM. Transforming growth factor-beta signaling promotes hepatocarcinogenesis induced by p53 loss. Hepatology 2012; 55:121-31. [PMID: 21898503 PMCID: PMC3237853 DOI: 10.1002/hep.24653] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/08/2011] [Accepted: 08/22/2011] [Indexed: 12/25/2022]
Abstract
UNLABELLED Hepatocellular carcinoma (HCC) results from the accumulation of deregulated tumor suppressor genes and/or oncogenes in hepatocytes. Inactivation of TP53 and inhibition of transforming growth factor-beta (TGF-β) signaling are among the most common molecular events in human liver cancers. Thus, we assessed whether inactivation of TGF-β signaling, by deletion of the TGF-β receptor, type II (Tgfbr2), cooperates with Trp53 loss to drive HCC formation. Albumin-cre transgenic mice were crossed with floxed Trp53 and/or floxed Tgfbr2 mice to generate mice lacking p53 and/or Tgfbr2 in the liver. Deletion of Trp53 alone (Trp53(KO) ) resulted in liver tumors in approximately 41% of mice by 10 months of age, whereas inactivation of Tgfbr2 alone (Tgfbr2(KO) ) did not induce liver tumors. Surprisingly, deletion of Tgfbr2 in the setting of p53 loss (Trp53(KO) ;Tgfbr2(KO) ) decreased the frequency of mice with liver tumors to around 17% and delayed the age of tumor onset. Interestingly, Trp53(KO) and Trp53(KO) ;Tgfbr2(KO) mice develop both HCC and cholangiocarcinomas, suggesting that loss of p53, independent of TGF-β, may affect liver tumor formation through effects on a common liver stem cell population. Assessment of potential mechanisms through which TGF-β signaling may promote liver tumor formation in the setting of p53 loss revealed a subset of Trp53(KO) tumors that express increased levels of alpha-fetoprotein. Furthermore, tumors from Trp53(KO) mice express increased TGF-β1 levels compared with tumors from Trp53(KO) ;Tgfbr2(KO) mice. Increased phosphorylated Smad3 and ERK1/2 expression was also detected in the tumors from Trp53(KO) mice and correlated with increased expression of the TGF-β responsive genes, Pai1 and Ctgf. CONCLUSION TGF-β signaling paradoxically promotes the formation of liver tumors that arise in the setting of p53 inactivation.
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Affiliation(s)
- Shelli M. Morris
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
| | - Ji Yeon Baek
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
,Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea
| | - Amanda Koszarek
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
| | - Samornmas Kanngurn
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
,Department of Pathology, Prince of Songkla University, Hat Yai, Thailand
| | - Sue E. Knoblaugh
- Animal Health Resources, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
| | - William M. Grady
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109 USA
,Department of Medicine, University of Washington Medical School, Seattle, WA 98195 USA
,Corresponding Author: William M. Grady, MD, Fred Hutchinson Cancer Research Center, Clinical Research Division, 1100 Fairview Ave. N, Mailstop D4-100, Seattle, WA 98109-1024, Phone: 206-667-1107, Fax: 206-667-2917,
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Morris SM, Baek JY, Koszarek A, Kanngurn S, Knoblaugh SE, Grady WM. Transforming growth factor-beta signaling promotes hepatocarcinogenesis induced by p53 loss. Hepatology 2011. [PMID: 21898503 DOI: 10.1002/hep.2465] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
UNLABELLED Hepatocellular carcinoma (HCC) results from the accumulation of deregulated tumor suppressor genes and/or oncogenes in hepatocytes. Inactivation of TP53 and inhibition of transforming growth factor-beta (TGF-β) signaling are among the most common molecular events in human liver cancers. Thus, we assessed whether inactivation of TGF-β signaling, by deletion of the TGF-β receptor, type II (Tgfbr2), cooperates with Trp53 loss to drive HCC formation. Albumin-cre transgenic mice were crossed with floxed Trp53 and/or floxed Tgfbr2 mice to generate mice lacking p53 and/or Tgfbr2 in the liver. Deletion of Trp53 alone (Trp53(KO) ) resulted in liver tumors in approximately 41% of mice by 10 months of age, whereas inactivation of Tgfbr2 alone (Tgfbr2(KO) ) did not induce liver tumors. Surprisingly, deletion of Tgfbr2 in the setting of p53 loss (Trp53(KO) ;Tgfbr2(KO) ) decreased the frequency of mice with liver tumors to around 17% and delayed the age of tumor onset. Interestingly, Trp53(KO) and Trp53(KO) ;Tgfbr2(KO) mice develop both HCC and cholangiocarcinomas, suggesting that loss of p53, independent of TGF-β, may affect liver tumor formation through effects on a common liver stem cell population. Assessment of potential mechanisms through which TGF-β signaling may promote liver tumor formation in the setting of p53 loss revealed a subset of Trp53(KO) tumors that express increased levels of alpha-fetoprotein. Furthermore, tumors from Trp53(KO) mice express increased TGF-β1 levels compared with tumors from Trp53(KO) ;Tgfbr2(KO) mice. Increased phosphorylated Smad3 and ERK1/2 expression was also detected in the tumors from Trp53(KO) mice and correlated with increased expression of the TGF-β responsive genes, Pai1 and Ctgf. CONCLUSION TGF-β signaling paradoxically promotes the formation of liver tumors that arise in the setting of p53 inactivation.
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Affiliation(s)
- Shelli M Morris
- Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA
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Morris SM, Baek JY, Koszarek A, Kanngurn S, Knoblaugh SE, Grady WM. Abstract 2415: TGF-ß signaling inactivation inhibits the formation of hepatocellular carcinomas induced by loss of p53. Cancer Res 2011. [DOI: 10.1158/1538-7445.am2011-2415] [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
Background: Hepatocellular carcinoma (HCC) is one of the most deadly forms of cancer and results from the accumulation of mutated or altered tumor suppressor genes and/or oncogenes. The tumor suppressor and oncogenes commonly affected include growth factors, receptors and downstream signaling components. Inactivation of the TGF-ß signaling pathway and mutation of TP53, the gene for p53, are common in HCCs suggesting they may cooperate in HCC formation. Thus, we assessed whether inactivation of TGF-ß signaling, by deletion of the TGF-ß receptor type II, TGFBR2, affects the formation of HCCs arising secondary to loss of p53.
Aim: To determine if loss of TGFBR2 and p53 cooperate in vivo to affect HCC formation.
Methods and Results: Albumin-cre (Alb-Cre) transgenic mice were crossed with mice homozygous for floxed Tgfbr2 (Tgfbr2flx/flx) and/or floxed Trp53 (Trp53flx/flx) to generate mice lacking TGFBR2 and/or p53 in the liver. Deletion of Tgfbr2 alone did not induce liver tumors, while inactivation of both Tgfbr2 and Trp53 resulted in a subset of mice (19%) that developed liver tumors by 65 weeks of age. Surprisingly, deletion of p53 alone, in the context of intact TGF-ß receptors, resulted in an increased number of mice developing tumors (38%), as well as increased morbidity (42 weeks of age). Interestingly, in both genotypes, Alb-Cre;Trp53flx/flx;Tgfbr2flx/flx and Alb-Cre;Trp53flx/flx;Tgfbr2wt/wt, the mice develop both hepatocellular carcinomas (HCC) and cholangiocarcinomas (CC), suggesting these tumors originate from a common liver stem cell population. Quantitative RT-PCR analysis of tumor and non-tumor tissue demonstrated a subset of Alb-Cre;Trp53flx/flx;Tgfbr2wt/wt (p53 null) tumors express significantly increased levels of alpha-fetoprotein mRNA, a clinical marker for HCC. Additionally, tumors from the Alb-Cre;Trp53flx/flx;Tgfbr2wt/wt displayed increased TGFβ-1 protein levels as compared to tumors from Trp53 and Tgfbr2 null mice. Furthermore, increased phosphorylated ERK1/2 expression was also present in the tumors from the p53 null mice and correlated with a slight up-regulation in beta-catenin expression, another common molecular event observed in human HCC.
Conclusions: The Alb-Cre;Trp53flx/flx;Tgfbr2flx/flx mouse model recapitulates many molecular features of human HCC and demonstrates that TGF-ß signaling is oncogenic in the setting of loss of p53 in the liver.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2415. doi:10.1158/1538-7445.AM2011-2415
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Affiliation(s)
| | - Ji Yeon Baek
- 1Fred Hutchinson Cancer Research Center, Seattle, WA
| | | | - Samornmas Kanngurn
- 2Prince of Songkla University, Department of Pathology, Hatyai, Thailand
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Martel CM, Parker JE, Jackson CJ, Warrilow AGS, Rolley N, Greig C, Morris SM, Donnison IS, Kelly DE, Kelly SL. Expression of bacterial levanase in yeast enables simultaneous saccharification and fermentation of grass juice to bioethanol. Bioresour Technol 2011; 102:1503-8. [PMID: 20801645 DOI: 10.1016/j.biortech.2010.07.099] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2010] [Revised: 07/21/2010] [Accepted: 07/22/2010] [Indexed: 05/13/2023]
Abstract
This study demonstrates use of recombinant yeast to simultaneously saccharify and ferment grass juice (GJ) to bioethanol. A modified Bacillus subtilis levanase gene (sacC) in which the native bacterial signal sequence was replaced with a yeast α-factor domain, was synthesised with yeast codon preferences and transformed into Saccharomyces cerevisiae (strain AH22) using the expression vector pMA91. AH22:psacC transformants secreted sacCp as an active, hyper-glycosylated (>180 kDa) protein allowing them to utilise inulin (β[2-1] linked fructose) and levan (β[2-6] linkages) as growth substrates. The control (AH22:pMA91) strain, transformed with empty plasmid DNA was not able to utilise inulin or levan. When cultured on untreated GJ levels of growth and bioethanol production were significantly higher in experiments with AH22:psacC than with AH22:pMA91. Bioethanol yields from AH22:psacC grown on GJ (32.7[±4] mg mL(-1)) compared closely to those recently achieved (Martel et al., 2010) using enzymatically pre-hydrolysed GJ (36.8[±4] mg mL(-1)).
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Affiliation(s)
- C M Martel
- Institute of Life Science and School of Medicine, Swansea University, Swansea SA2 8PP, Wales, UK
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Baek JY, Morris SM, Campbell J, Fausto N, Yeh MM, Grady WM. TGF-beta inactivation and TGF-alpha overexpression cooperate in an in vivo mouse model to induce hepatocellular carcinoma that recapitulates molecular features of human liver cancer. Int J Cancer 2010; 127:1060-71. [PMID: 20020490 DOI: 10.1002/ijc.25127] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Hepatocellular carcinoma (HCC) results from the cumulative effects of deregulated tumor suppressor genes and oncogenes. The tumor suppressor and oncogenes commonly affected include growth factors, receptors and their downstream signaling pathway components. The overexpression of transforming growth factor alpha (TGF-alpha) and the inhibition of TGF-beta signaling are especially common in human liver cancer. Thus, we assessed whether TGF-alpha overexpression and TGF-beta signaling inactivation cooperate in hepatocarcinogenesis using an in vivo mouse model, MT1/TGFa;AlbCre/Tgfbr2(flx/flx) mice ("TGFa;Tgfbr2(hepko)"), which overexpresses TGF-alpha and lacks a TGF-beta receptor in the liver. TGF-beta signaling inactivation did not alter the frequency or number of cancers in mice with overexpression of TGF-alpha. However, the tumors in the TGFa;Tgfbr2(hepko) mice displayed increased proliferation and increased cdk2, cyclin E and cyclin A expression as well as decreased Cdkn1a/p21 expression compared to normal liver and compared to the cancers arising in the TGF-alpha overexpressing mice with intact TGF-beta receptors. Increased phosphorylated ERK1/2 expression was also present in the tumors from the TGFa;Tgfbr2(hepko) mice and correlated with downregulated Raf kinase inhibitor protein expression, which is a common molecular event in human HCC. Thus, TGF-beta signaling inactivation appears to cooperate with TGF-alpha in vivo to promote the formation of liver cancer that recapitulates molecular features of human HCC.
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Affiliation(s)
- Ji Yeon Baek
- Center for Colorectal Cancer, Research Institute and Hospital, National Cancer Center, Goyang, Republic of Korea
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Castles F, Morris SM, Terentjev EM, Coles HJ. Thermodynamically stable blue phases. Phys Rev Lett 2010; 104:157801. [PMID: 20482018 DOI: 10.1103/physrevlett.104.157801] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 11/02/2009] [Indexed: 05/29/2023]
Abstract
We show theoretically that flexoelectricity stabilizes blue phases in chiral liquid crystals. Induced internal polarization reduces the elastic energy cost of splay and bend deformations surrounding singular lines in the director field. The energy of regions of double twist is unchanged. This in turn reduces the free energy of the blue phase with respect to that of the chiral nematic phase, leading to stability over a wider temperature range. The theory explains the discovery of large temperature range blue phases in highly flexoelectric "bimesogenic" and "bent-core" materials, and predicts how this range may be increased further.
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Affiliation(s)
- F Castles
- Centre of Molecular Materials for Photonics and Electronics, Department of Engineering, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
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Rodriguez JS, Morris SM, Hotchkiss CE, Doerge DR, Allen RR, Mattison DR, Paule MG. The effects of chronic methylphenidate administration on operant test battery performance in juvenile rhesus monkeys. Neurotoxicol Teratol 2010; 32:142-51. [PMID: 19737611 PMCID: PMC2942084 DOI: 10.1016/j.ntt.2009.08.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2009] [Revised: 08/26/2009] [Accepted: 08/27/2009] [Indexed: 11/17/2022]
Abstract
Methylphenidate (MPH) is an amphetamine derivative widely prescribed for the treatment of attention deficit-hyperactivity disorder. Recent concern over its genotoxic potential in children [11] spurred a study on the effects of chronic MPH treatment in a nonhuman primate population and the studies reported here were conducted in conjunction with that study in the same animals. Here, the focus was on the ability of juvenile rhesus monkeys to learn how to perform a battery of operant behavioral tasks while being treated chronically with MPH. Performance of the National Center for Toxicological Research (NCTR) Operant Test Battery (OTB) was used to quantify the learning of tasks thought to model specific aspects of cognitive function including learning, motivation, color and position discrimination, and short-term memory. The OTB tasks designed to assess these specific behaviors included Incremental Repeated Acquisition (IRA), Progressive Ratio (PR), Conditioned Position Responding (CPR), and Delayed Matching-to-Sample (DMTS), respectively. Juvenile males (n=10/group) pressed levers and press-plates for banana-flavored food pellets. Subjects were treated orally, twice a day, five days per week (M-F) for 66 weeks with escalating doses (0.15 mg/kg initially, increased to 2.5 mg/kg for the low dose group and to 12.5 mg/kg for the high dose group) and tested in OTB tasks 30 to 60 min after the morning dose. The findings indicate that MPH at doses up to 2.5 mg/kg twice per day were well tolerated (performance was no different than controls) but at doses of 12.5 mg/kg twice per day there was a significant decrement in OTB performance, characterized by decreases in both percent task completed and response rates for all tasks. These effects of MPH seem primarily due to decreases in motivation to perform for food, which is not surprising given the well known appetite suppressing effects of amphetamine-like stimulants. Thus, the current data do not strongly suggest cognitive impairments following chronic MPH administration.
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Affiliation(s)
- J S Rodriguez
- Division of Neurotoxicology, National Center for Toxicological Research, FDA, Jefferson, AR, United States.
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Castles F, Morris SM, Coles HJ. Flexoelectro-optic properties of chiral nematic liquid crystals in the uniform standing helix configuration. Phys Rev E Stat Nonlin Soft Matter Phys 2009; 80:031709. [PMID: 19905133 DOI: 10.1103/physreve.80.031709] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2009] [Revised: 07/30/2009] [Indexed: 05/28/2023]
Abstract
The flexoelectro-optic effect describes the rotation of the optic axis of a short-pitch chiral nematic liquid crystal under the application of an electric field. We investigate the effect in the uniform standing helix, or "Grandjean" configuration. An in-plane electric field is applied. The director profile is determined numerically using a static one-dimensional continuum model with strong surface anchoring. The Berreman method is used to solve for plane-wave solutions to Maxwell's equations, and predict the optical properties of the resulting structure in general cases. By using a chiral nematic with short pitch between crossed polarizers an optical switch may be generated. With no applied field the configuration is nontransmissive at normal incidence, but becomes transmissive with an applied field. For this case, numerical results using the Berreman method are supplemented with an analytic theory and found to be in good agreement. The transmitted intensity as a function of tilt, the contrast ratio, and the tilt required for full intensity modulation are presented. The angular dependence of the transmission is calculated and the isocontrast curves are plotted. For typical material and cell parameters a switching speed of 0.017 ms and contrast ratio of 1500:1 at normal incidence are predicted, at a switch-on tilt of 41.5 degrees. Experimental verification of the analytic and numerical models is provided.
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Affiliation(s)
- F Castles
- Electrical Engineering Division, Department of Engineering, Centre of Molecular Materials for Photonics and Electronics, University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom.
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Ford AD, Morris SM, Pivnenko MN, Gillespie C, Coles HJ. Emission characteristics of a homologous series of bimesogenic liquid-crystal lasers. Phys Rev E Stat Nonlin Soft Matter Phys 2007; 76:051703. [PMID: 18233669 DOI: 10.1103/physreve.76.051703] [Citation(s) in RCA: 3] [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: 07/27/2007] [Indexed: 05/25/2023]
Abstract
In this study we have fabricated eight different liquid-crystal lasers using the same gain medium but different homologues from the bimesogenic series alpha-(2',4-difluorobiphenyl-4'-yloxy)-omega-(4-cyanobiphenyl-4'-yloxy)alkanes, whereby the number of methylene units in the spacer chain varied from n=5 to n=12. To quantify the performance of these lasers, the threshold energy and the slope efficiency were extracted from the input-output characteristics of each laser. A clear odd-even effect was observed when both the excitation threshold and the slope efficiency were plotted as a function of the number of methylene units in the spacer chain. In all cases, the bimesogen lasers for which n is even exhibit lower threshold energies and higher slope efficiencies than those for which n is odd. These results are then interpreted in terms of the macroscopic physical properties of the liquid-crystalline compounds. In accordance with a previous study [S. M. Morris, A. D. Ford, M. N. Pivnenko, O. Hadeler, and H. J. Coles, Phys. Rev. E. 74, 061709 (2006)], a combination of a large birefringence and high order parameters are found, in the most part, to correlate with low-threshold energy and high slope efficiency. This indicates that the threshold and slope efficiency are dominated by the host macroscopic properties as opposed to intermolecular interactions between the dye and the liquid crystal. However, certain differences in the slope efficiency could not be explained by the birefringence and order parameter values alone. Instead, we find that the slope efficiency is further increased by increasing the elastic constants of the liquid-crystal host so as to decrease the scattering losses incurred by local distortions in the director field under high-energy optical excitation.
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Affiliation(s)
- A D Ford
- Centre of Molecular Materials for Photonics and Electronics, Electrical Engineering Division, Engineering Department, Cambridge University, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdom
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Morris SM, Clarke MJ, Blatch AE, Coles HJ. Structure-flexoelastic properties of bimesogenic liquid crystals. Phys Rev E Stat Nonlin Soft Matter Phys 2007; 75:041701. [PMID: 17500907 DOI: 10.1103/physreve.75.041701] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2006] [Revised: 01/09/2007] [Indexed: 05/15/2023]
Abstract
In this paper, we report on the flexoelastic and viscoelastic ratios for a number of bimesogens compounds with the same generic structure. Values are obtained indirectly by measuring the flexoelectro-optic response in the chiral nematic phase. By varying the molecular structure we alter the bend angle, transverse dipole moment, and length of the molecule. First, to examine the influence of the bend angle we use a homologous series whereby the only alteration in the molecular structure is the number of methylene units in the aliphatic spacer, n . Results show that the flexoelastic ratio, e/K , and the effective flexoelectric coefficient, e , both exhibit an odd-even effect with values for n=odd being greater than that for n=even . This is understood in terms of an increase in the bend angle of the molecule and an increase in the transverse dipole moment. Second, in order to investigate the impact of the dipole moment, we have altered the mesogenic units so as to vary the longitudinal dipole moment and used different linkages in the aliphatic spacer in an attempt to alter the transverse dipole moment. Qualitatively, the results demonstrate that the odd-spaced bimesogen with larger transverse dipole moments exhibit larger flexoelastic ratios.
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Affiliation(s)
- S M Morris
- Centre of Molecular Materials for Photonics and Electronics, Electrical Engineering Division, Department of Engineering, Cambridge University, 9 J J Thomson Avenue, Cambridge CB3 0FA, United Kingdom.
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Morris SM, Ford AD, Pivnenko MN, Hadeler O, Coles HJ. Correlations between the performance characteristics of a liquid crystal laser and the macroscopic material properties. Phys Rev E Stat Nonlin Soft Matter Phys 2006; 74:061709. [PMID: 17280086 DOI: 10.1103/physreve.74.061709] [Citation(s) in RCA: 1] [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: 08/02/2006] [Indexed: 05/13/2023]
Abstract
In order to understand how the performance of a liquid-crystal laser depends on the physical properties of the low molar mass nematic host, we have studied the energy threshold and slope efficiency of ten optically pumped liquid-crystal lasers based on different hosts. Specifically, this leads to a variation in the birefringence, the orientational order parameter, and the order parameter of the transition dipole moment of the dye. It is found that low threshold energies and high slope efficiencies correlate with high order parameters and large birefringences. To a first approximation this can be understood by considering analytical expressions for the threshold and slope efficiency, which are derived from the space-independent rate equations for a two-level system, in terms of the macroscopic liquid crystal properties.
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Affiliation(s)
- S M Morris
- Centre of Molecular Materials for Photonics and Electronics, Electrical Engineering Division, Cambridge University Engineering Department, 9 JJ Thomson Avenue, Cambridge, CB3 0FA, United Kingdom.
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Nagai J, Christensen EI, Morris SM, Willnow TE, Cooper JA, Nielsen R. Mutually dependent localization of megalin and Dab2 in the renal proximal tubule. Am J Physiol Renal Physiol 2005; 289:F569-76. [PMID: 15870384 DOI: 10.1152/ajprenal.00292.2004] [Citation(s) in RCA: 75] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Disabled-2 (Dab2) is a cytoplasmic adaptor protein that binds to the cytoplasmic tail of the multiligand endocytic receptor megalin, abundantly expressed in renal proximal tubules. Deletion of Dab2 induces a urinary increase in specific plasma proteins such as vitamin D binding protein and retinol binding protein (Morris SM, Tallquist MD, Rock CO, and Cooper JA. EMBO J 21: 1555-1564, 2002). However, the subcellular localization of Dab2 in the renal proximal tubule and its function have not been fully elucidated yet. Here, we report the characterization of Dab2 in the renal proximal tubule. Immunohistocytochemistry revealed colocalization with megalin in coated pits and vesicles but not in dense apical tubules and the brush border. Kidney-specific megalin knockout almost abolished Dab2 staining, indicating that Dab2 subcellular localization requires megalin in the proximal tubule. Reciprocally, knockout of Dab2 led to a redistribution of megalin from endosomes to microvilli. In addition, there was an overall decrease in levels of megalin protein observed by immunoblotting but no decrease in clathrin or alpha-adaptin protein levels or in megalin mRNA. In rat yolk sac epithelial BN16 cells, Dab2 was present apically and colocalized with megalin. Introduction of anti-Dab2 antibody into BN16 cells decreased the internalization of 125I-labeled receptor-associated protein, substantiating the role of Dab2 in megalin-mediated endocytosis. The present study shows that Dab2 is localized in the apical endocytic apparatus of the renal proximal tubule and that this localization requires megalin. Furthermore, the study suggests that the urinary loss of megalin ligands observed in Dab2 knockout mice is caused by suboptimal trafficking of megalin, leading to decreased megalin levels.
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Affiliation(s)
- J Nagai
- Cell Biology, Institute of Anatomy, Univ. of Aarhus, University Park, Bldg. 234, DK-8000 Aarhus C, Denmark
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Morris SM, Ford AD, Pivnenko MN, Coles HJ. The effects of reorientation on the emission properties of a photonic band edge liquid crystal laser. ACTA ACUST UNITED AC 2005. [DOI: 10.1088/1464-4258/7/5/002] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Akerman GS, Rosenzweig BA, Domon OE, McGarrity LJ, Blankenship LR, Tsai CA, Culp SJ, MacGregor JT, Sistare FD, Chen JJ, Morris SM. Gene expression profiles and genetic damage in benzo(a)pyrene diol epoxide-exposed TK6 cells. Mutat Res 2004; 549:43-64. [PMID: 15120962 DOI: 10.1016/j.mrfmmm.2003.11.013] [Citation(s) in RCA: 56] [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] [Received: 07/21/2003] [Revised: 11/21/2003] [Accepted: 11/25/2003] [Indexed: 12/23/2022]
Abstract
Microarray analysis is a powerful tool to identify the biological effects of drugs or chemicals on cellular gene expression. In this study, we compare the relationships between traditional measures of genetic toxicology and mutagen-induced alterations in gene expression profiles. TK6 cells were incubated with 0.01, 0.1, or 1.0 microM +/-anti-benzo(a)pyrene-trans-7,8-dihydrodiol-9,10-epoxide (BPDE) for 4 h and then cultured for an additional 20 h. Aliquots of the exposed cells were removed at 4 and 24 h in order to quantify DNA adduct levels by 32P post-labeling and measure cell viability by cloning efficiency and flow cytometry. Gene expression profiles were developed by extracting total RNA from the control and exposed cells at 4 and 24 h, labeling with Cy3 or Cy5 and hybridizing to a human 350 gene array. Mutant frequencies in the Thymidine Kinase and Hypoxanthine Phosphoribosyl Transferase genes were also determined. The 10alpha-(deoxyguanosin-N(2)-yl)-7alpha,8beta,9beta-trihydroxy-7,8,9,10-tetrahydrobenzo(a)pyrene (dG-N(2)-BPDE) adduct increased as a function of dose and was the only adduct identified. A dose-related decrease in cell viability was evident at 24 h, but not at 4 h. Cell death occurred by apoptosis. At 4 h, analysis of the gene expression profiles revealed that Glutathione Peroxidase and Gadd45 were consistently upregulated (greater than 1.5-fold and significantly (P < 0.001) greater than the control in two experiments) in response to 1.0 microM BPDE exposure. Fifteen genes were consistently down-regulated (less than 0.67-fold and significantly (P < 0.001) lower than the control in two experiments) at 4 h in cultures exposed to 1.0 microM BPDE. Genes with altered expression at 4 h included genes important in the progression of the cell-cycle and those that inhibit apoptosis. At 24 h post-exposure, 16 genes, involved in cell-cycle control, detoxification, and apoptosis were consistently upregulated; 10 genes were repressed in cultures exposed to the high dose of BPDE. Real-time quantitative PCR confirmed the differential expression of selected genes. These data suggest that changes in gene expression will help to identify effects of drugs and chemicals on molecular pathways in cells, and will provide useful information about the molecular responses associated with DNA damage. Of the endpoints evaluated, DNA adduct formation was the most sensitive indicator of DNA damage. DNA adduct formation was clearly evident at low doses, but the number of genes with significantly altered expression (P < 0.001) was minimal. Alterations in gene expression were more robust at doses associated with cellular toxicity and induction of mutations.
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Affiliation(s)
- G S Akerman
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, US Food and Drug Administration, 3900 NCTR Road, Jefferson, AR 72079, USA
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Abstract
The place of death of cancer patients has become an important theme in UK cancer and palliative care policy. This paper examines the place of death preferences of 41 terminally ill cancer patients and 18 of their informal carers, living in the Morecambe Bay area of north-west England. We interviewed cancer patients referred to the research team by 13 specialist palliative care professionals; patients had an estimated 3 months of life remaining. The study design involved an in-depth qualitative interview with each patient soon after referral to the study, followed by an interview some 4 weeks later and subsequent tracking interviews by telephone at 2-4 week intervals until death occurred. Interviews were also conducted with main coresident carers soon after patient referral to the study and again in the post-bereavement period. Thirteen factors were identified as shaping the place of death preference of patients and carers. These are organised into four thematic domains: the informal care resource, management of the body, experience of services, and existential perspectives. In documenting these factors, this paper adds significantly to current knowledge on the factors that shape place of death preference, a field of enquiry acknowledged to be underdeveloped (J. Palliative Med. 3 (2000) 287). More importantly, it uncovers some of the reasons that underpin these preferences. Our research revealed a much stronger preference for deaths in a hospice than had been anticipated, leading us to take a qualified stance on the current policy drive in favour of home deaths by those charged with delivering UK cancer and palliative care services.
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Affiliation(s)
- C Thomas
- Institute for Health Research, Lancaster University, UK.
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Abstract
BACKGROUND This study aims to determine whether healthcare providers' (HCPs') communication dealing with sun-protection (i.e., counseling) is associated with clients' skin-cancer-related prevention practices, detection self-efficacy, and knowledge. METHODS Secondary analysis of two surveys of 1,469 randomly sampled farmers and soccer participants from southeast and coastal Georgia. RESULTS Farmers and soccer participants who report ever having been counseled by a HCP about how to protect their skin from the sun report being more likely to wear sunscreen (P < 0.05), get clinical exams of their skin (P < 0.001), be certain that they can recognize unhealthy changes in their skin (P < 0.001), be certain that they know how to perform a skin exam (P < 0.001), and be knowledgeable about skin cancer prevention (P < 0.05 and P < 0.001, respectively); soccer participants are additionally more likely to wear protective headgear (P < 0.05) and perform monthly self-exams of their skin (P < 0.001). All analyses incorporated three control variables: participants' prior history of skin cancer, age, and non-HCP-derived skin-cancer awareness. CONCLUSIONS Findings suggest that HCPs' counseling can positively shape skin-cancer-related prevention practices, detection self-efficacy, and knowledge. Additional research is needed on HCPs' actual communication about skin cancer and sun protection and its influence on client outcomes.
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Affiliation(s)
- J D Robinson
- Department of Communication Arts and Sciences, Pennsylvania State University, University Park, PA 16802, USA
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Hocevar BA, Mou F, Rennolds JL, Morris SM, Cooper JA, Howe PH. Regulation of the Wnt signaling pathway by disabled-2 (Dab2). EMBO J 2003; 22:3084-94. [PMID: 12805222 PMCID: PMC162138 DOI: 10.1093/emboj/cdg286] [Citation(s) in RCA: 112] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2002] [Revised: 04/04/2003] [Accepted: 04/23/2003] [Indexed: 02/06/2023] Open
Abstract
The adaptor molecule Disabled-2 (Dab2) has been shown to link cell surface receptors to downstream signaling pathways. Using a small-pool cDNA screening strategy, we identify that the N-terminal domain of Dab2 interacts with Dishevelled-3 (Dvl-3), a signaling mediator of the Wnt pathway. Ectopic expression of Dab2 in NIH-3T3 mouse fibroblasts attenuates canonical Wnt/beta-catenin-mediated signaling, including accumulation of beta-catenin, activation of beta-catenin/T-cell-specific factor/lymphoid enhancer-binding factor 1-dependent reporter constructs, and endogenous cyclin D1 induction. Wnt stimulation leads to a time-dependent dissociation of endogenous Dab2-Dvl-3 and Dvl-3-axin interactions in NIH-3T3 cells, while Dab2 overexpression leads to maintenance of Dab2-Dvl-3 association and subsequent loss of Dvl-3-axin interactions. In addition, we find that Dab2 can associate with axin in vitro and stabilize axin expression in vivo. Mouse embryo fibroblasts which lack Dab2 exhibit constitutive Wnt signaling as evidenced by increased levels of nuclear beta-catenin and cyclin D1 protein levels. Based on these results, we propose that Dab2 functions as a negative regulator of canonical Wnt signaling by stabilizing the beta-catenin degradation complex, which may contribute to its proposed role as a tumor suppressor.
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Affiliation(s)
- B A Hocevar
- Department of Cell Biology, The Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195, USA
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Abstract
The phytoestrogen and isoflavone, genistein, inhibited the activity of the DNA synthesis-related enzyme, topoisomerase-II (topo-II), altered cell-cycle traverse and produced cell death in cell culture models. In order to examine the potential effects of genistein on cell replication and cell death in an animal model, 8-week-old C57BL6 mice were fed either a control diet or one containing one of five doses (100-2000 ppm) of genistein for 28 days. At the end of the feeding period, both male and female mice were sacrificed and the serum isoflavone and aglycone levels determined by liquid chromatography with electrospray tandem mass spectrometry (LC-ES/MS/MS). Immunohistochemistry was utilized to measure the cell replication and cell death rates in the small intestine. Total isoflavone concentration increased from below the limits of detection (0.001 microM) in control animals to 0.28 microM in male and 0.54 microM in female mice fed the 2000 ppm diet. A decrease in the percentage of cells in G(0) and an increase in the percentage of cells in S-phase, consistent with topo-II-induced S-phase arrest, was found in the duodenum and jejunum of the small intestine. Thus, genistein appears to accumulate to a sufficient level to affect topo-II activity in the small intestine.
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Affiliation(s)
- S M Morris
- Division of Genetic and Reproductive Toxicology, National Center for Toxicological Research, US Food and Drug Administration, HFT-120/DGRT/NCTR, 3900 NCTR Road, Jefferson, AR 72079, USA.
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Soothill K, Morris SM, Thomas C, Harman JC, Francis B, McIllmurray MB. The universal, situational, and personal needs of cancer patients and their main carers. Eur J Oncol Nurs 2003; 7:5-13; discussion 14-6. [PMID: 12849570 DOI: 10.1054/ejon.2002.0226] [Citation(s) in RCA: 79] [Impact Index Per Article: 3.8] [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: 11/18/2022]
Abstract
The importance of psychosocial factors in the cancer journey for both patients and their carers has been recognised in UK health policy. The aim of this paper is to consider--(1) which needs are regarded as important by patients and their carers; (2) which are the unmet needs of patients and their carers. The study focuses on the responses of 233 paired cancer patients and their carers derived from a cross-sectional questionnaire survey in three health authorities in North West England. The majority of patient-carer pairs expressed the importance of having good relationships with health-care professionals and receiving good-quality information. These can be identified as "universal" needs. A minority of patient-carer pairs expressed the importance of other kinds of needs. These items were mainly to do with managing daily life, emotions, and social identity and can be identified as "situational" or "personal" needs. Where there were discrepancies between patients and carers, patients were likely to identify more needs as important. In contrast, carers have more unmet needs, reflecting their comparative neglect. Broadly, "universal" needs are being met, but "situational" and "personal" needs, particularly among carers, are relatively unmet and require greater attention on the part of nurses and primary care professionals.
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Affiliation(s)
- K Soothill
- Department of Applied Social Science, Cartmel College, Lancaster University, Lancaster, LA1 4YL, UK.
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Abstract
In a study of psychosocial needs amongst cancer patients, the possession of a religious faith has been identified as a significant factor in determining a range of psychosocial needs. Of the 354 respondents to a questionnaire, which included a comprehensive psychosocial needs inventory, 83% said they had a religious faith, and in general these patients were less reliant on health professionals, had less need for information, attached less importance to the maintenance of independence and had less need for help with feelings of guilt, with their sexuality or with some practical matters than those who said they had no religious faith. In addition, they had fewer unmet needs overall (32% compared with 52%). The knowledge of a patient's spirituality should help service providers to predict aspects of psychosocial need and to respond sensitively and appropriately to a patient's experience of cancer.
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Stickings P, Mistry SK, Boucher JL, Morris SM, Cunningham JM. Arginase expression and modulation of IL-1beta-induced nitric oxide generation in rat and human islets of Langerhans. Nitric Oxide 2002; 7:289-96. [PMID: 12446178 DOI: 10.1016/s1089-8603(02)00122-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Proinflammatory cytokine induction of NO synthesis may contribute to the destruction of pancreatic beta cells leading to type 1 diabetes. The NO synthase substrate arginine can also be metabolized to ornithine and urea in a reaction catalyzed by cytosolic (AI) or mitochondrial (AII) isoforms of arginase. Recent evidence suggests that the rate of NO generation is dependent on the relative activities of NO synthase and arginase. The objectives of this study were (i). to identify the arginase isoforms expressed in rat and human islets of Langerhans and a rat beta cell line, RINm5F and (ii). to investigate the competition for arginine between NO synthase and arginase in IL-1beta-treated rat islets. Arginase activity was detected in rat islets (fresh tissue, 346 mU/mg protein; cultured, 587 mU/mg), cultured human islets (56 mU/mg), RINm5F cells (376 mU/mg), rat kidney (238 mU/mg), and rat liver (6119 mU/mg). Using Western blots, AI was shown to be the predominant isoform expressed in rat islets and in RINm5F cells while human islets expressed far more AII than AI. Rat islets were cultured in medium containing 1.14, 0.1, and 0.01 mM arginine and treated with IL-1beta and the arginase inhibitor 2(S)-amino-6-boronohexanoic acid (ABH). IL-1beta-induced NO generation was unaffected by ABH at 1.14 mM arginine, but significantly increased at 0.1 and 0.01 mM arginine. These findings suggest that the level of islet arginase activity can regulate the rate of induced NO generation and this may be relevant to the insulitis process leading to beta cell destruction in type 1 diabetes.
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Affiliation(s)
- P Stickings
- School of Pharmacy and Biomolecular Sciences, University of Brighton, Cockcroft Building Lewes Rd, Brighton, East Sussex, BN2 4GJ UK
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Abstract
This paper considers some of the challenges involved in studying informal carers in cancer contexts. It reviews current knowledge by examining, first, the dominant psycho-oncological research tradition that focuses on psychological distress among carers and, second, the more recent sociologically informed body of work examining what carers actually do and the contribution that they make to patient care. The authors suggest that this second sociologically informed approach offers an important counter-weight to the psycho-oncological perspective. The developing research agenda for a sociology of cancer caring is briefly outlined.
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Affiliation(s)
- C Thomas
- Department of Applied Social Science, Institute for Health Research, Lancaster University, Cartmel College, Lancaster, UK.
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Abstract
There is a growing recognition that the carers of cancer patients require information. A key source of this information is the formal health care system that patients, and thus carers, encounter. However, the research literature suggests a lack of clarity on the part of service providers concerning the type, amount, timing and purpose of information for carers. This lack of clarity is reflected in the ways carers have been 'tacked on' to patients and thus are often treated as co-clients. That carers are also an active participants in the illness scenario is not always fully recognized, resulting in failure to provide appropriate information. Carers' interactions with health service providers are complex and context bound, and entail potential tensions of allegiance in the arena of information exchange. This article suggests that the following research and practice is required: a clearer understanding of the informational needs of carers in variable situations, specific ways to address these needs, where carers 'fit in' to the health care system, and how processes of information exchange with carers can be improved.
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Affiliation(s)
- S M Morris
- Department of Applied Social Science, Institute for Health Research, Lancaster University, Cartmel College, Lancaster, UK.
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Soothill K, Morris SM, Harman JC, Thomas C, Francis B, McIllmurray MB. Cancer and faith. Having faith--does it make a difference among patients and their informal carers? Scand J Caring Sci 2002; 16:256-63. [PMID: 12191037 DOI: 10.1046/j.1471-6712.2002.00097.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [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: 11/20/2022]
Abstract
This research considers the impact of having a religious faith on the cancer experience of patients and informal carers, focusing primarily on the association between faith and psychosocial needs. A questionnaire survey of 1000 patients in the north-west of England returned 402 completed questionnaires; around two-thirds of patients indicated they had an informal carer. Using logistic regression analysis, we examine the relationship between the importance of 48 needs and faith for 189 paired patients and carers, while controlling for the effect of eight socio-demographic and clinical variables. Patients with expressed faith identified fewer psychosocial needs than those without faith. In contrast, carers with expressed faith identified more needs than those without faith in relation to support from family and neighbours. Carers also needed more help with finding a sense of purpose and meaning, and help in dealing with unpredictability. Not surprisingly, both patients and carers with faith identified a greater need for opportunities for personal prayer, support from people of their own faith and support from a spiritual adviser. Various explanations of these differences between patients and carers are proposed. The crucial point is that one should not too readily assume that the cancer experience is shared in the same way by patients and carers. In understanding the faith dimension, one needs to consider both the spiritual and secular aspects of having a religious faith.
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Affiliation(s)
- K Soothill
- Department of Applied Social Science, Lancaster University, Lancaster, UK.
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Glynias MJ, Morris SM, Fantozzi DA, Winberry LK, Back DW, Fisch JE, Goodridge AG. A cloned cDNA for duck malic enzyme detects abnormally large malic enzyme mRNAs in a strain of mice (Mod-1n) that does not express malic enzyme protein. Biochemistry 2002; 23:3454-9. [PMID: 6547851 DOI: 10.1021/bi00310a011] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sensitive immunochemical assays were used to measure the mass and rate of synthesis of malic enzyme protein in wild-type and Mod-1n mutant mice fed a high carbohydrate/low fat diet supplemented with thyroid hormone. Malic enzyme activity in the fed, wild-type mice was 100-fold higher than in starved, wild-type mice. Neither activity, mass, nor synthesis of malic enzyme could be detected in fed, mutant mice. However, glucose-6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase responded to these dietary manipulations with normal or supranormal increases in activities, respectively, in mutant mice. A cDNA clone containing an almost complete copy of the mRNA for malic enzyme from duck liver was used to analyze poly(A+) RNA from C57BL/6J-DBA/2J hybrid mice that had been fasted and refed a high carbohydrate/low fat diet supplemented with thyroid hormone. The 32P-cDNA probe hybridized to two RNAs of 2250 and 2950 nucleotides. The same two RNAs were detected in RNA from starved mice except at much lower concentrations. A similar analysis of RNA from Mod-1n mice fed the high carbohydrate-thyroid diet also revealed two hybridizing RNAs but each was 700-800 nucleotides longer than its counterpart in wild-type mice. The abundance of malic enzyme mRNA in the fed, mutant mice was about the same as that in fed, wild-type mice. The mutant malic enzyme mRNAs also were present in RNA from starved mice but at much lower concentrations. These results suggest that the mutation responsible for the Mod-1n phenotype is in the structural gene for malic enzyme.(ABSTRACT TRUNCATED AT 250 WORDS)
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Morris SM, Arden SD, Roberts RC, Kendrick-Jones J, Cooper JA, Luzio JP, Buss F. Myosin VI binds to and localises with Dab2, potentially linking receptor-mediated endocytosis and the actin cytoskeleton. Traffic 2002; 3:331-41. [PMID: 11967127 DOI: 10.1034/j.1600-0854.2002.30503.x] [Citation(s) in RCA: 209] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Myosin VI, an actin-based motor protein, and Disabled 2 (Dab2), a molecule involved in endocytosis and cell signalling, have been found to bind together using yeast and mammalian two-hybrid screens. In polarised epithelial cells, myosin VI is known to be associated with apical clathrin-coated vesicles and is believed to move them towards the minus end of actin filaments, away from the plasma membrane and into the cell. Dab2 belongs to a group of signal transduction proteins that bind in vitro to the FXNPXY sequence found in the cytosolic tails of members of the low-density lipoprotein receptor family. The central region of Dab2, containing two DPF motifs, binds to the clathrin adaptor protein AP-2, whereas a C-terminal region contains the binding site for myosin VI. This site is conserved in Dab1, the neuronal counterpart of Dab2. The interaction between Dab2 and myosin VI was confirmed by in vitro binding assays and coimmunoprecipitation and by their colocalisation in clathrin-coated pits/vesicles concentrated at the apical domain of polarised cells. These results suggest that the myosin VI-Dab2 interaction may be one link between the actin cytoskeleton and receptors undergoing endocytosis.
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Affiliation(s)
- Shelli M Morris
- Fred Hutchinson Cancer Research Center, Division of Basic Sciences, 1100 Fairview Avenue North, Seattle, WA 98109-1024, USA
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Abstract
The Disabled-2 (Dab2) gene has been proposed to act as a tumor suppressor. Cell culture studies have implicated Dab2 in signal transduction by mitogens, TGFbeta and endocytosis of lipoprotein receptors. To identify in vivo functions of Dab2, targeted mutations were made in the mouse. In the absence of Dab2, embryos arrest prior to gastrulation with a phenotype reminiscent of those caused by deletion of some TGFbeta signal transduction molecules involved in Nodal signaling. Dab2 is expressed in the extra-embryonic visceral endoderm but not in the epiblast. Dab2 could be conditionally deleted from the embryo without affecting normal development, showing that Dab2 is required in the visceral endoderm but dispensable in the embryo proper. Conditionally mutant Dab2(-/-) mice are overtly normal, but have reduced clathrin-coated pits in kidney proximal tubule cells and excrete specific plasma proteins in the urine, consistent with reduced transport by a lipoprotein receptor, megalin/gp330, in the proximal tubule. This evidence indicates that Dab2 is pleiotropic and regulates both visceral endoderm function and lipoprotein receptor trafficking in vivo.
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Affiliation(s)
- Shelli M. Morris
- Fred Hutchinson Cancer Research Center, Division of Basic Sciences, 1100 Fairview Avenue North, Seattle, WA 98109 and
St Jude Children’s Research Hospital, Protein Science Division, Department of Infectious Diseases, Memphis, TN 38101, USA Present address: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA Corresponding author e-mail:
| | - Michelle D. Tallquist
- Fred Hutchinson Cancer Research Center, Division of Basic Sciences, 1100 Fairview Avenue North, Seattle, WA 98109 and
St Jude Children’s Research Hospital, Protein Science Division, Department of Infectious Diseases, Memphis, TN 38101, USA Present address: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA Corresponding author e-mail:
| | - Charles O. Rock
- Fred Hutchinson Cancer Research Center, Division of Basic Sciences, 1100 Fairview Avenue North, Seattle, WA 98109 and
St Jude Children’s Research Hospital, Protein Science Division, Department of Infectious Diseases, Memphis, TN 38101, USA Present address: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA Corresponding author e-mail:
| | - Jonathan A. Cooper
- Fred Hutchinson Cancer Research Center, Division of Basic Sciences, 1100 Fairview Avenue North, Seattle, WA 98109 and
St Jude Children’s Research Hospital, Protein Science Division, Department of Infectious Diseases, Memphis, TN 38101, USA Present address: Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA Corresponding author e-mail:
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Soothill K, Morris SM, Harman JC, Francis B, Thomas C, McIllmurray MB. Informal carers of cancer patients: what are their unmet psychosocial needs? Health Soc Care Community 2001; 9:464-475. [PMID: 11846826 DOI: 10.1046/j.0966-0410.2001.00326.x] [Citation(s) in RCA: 98] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
This paper considers the significant unmet psychosocial needs of the informal carers of cancer patients, drawing on data generated in a 3-year UK study (1997-2000) on the psychosocial needs of cancer patients and their main carers. While the needs of the carers of cancer patients are increasingly being recognised in healthcare policy documents, there is relatively little published literature on these needs. A "significant unmet need" is defined here as a need deemed important by the carer, but which has not been met. A descriptive cross-sectional survey of carers was conducted and the responses of 195 carers relating to 48 psychosocial need items were analysed. A subset of these carers (n = 32) were interviewed. Forty-three per cent of carers had significant unmet needs. They were more likely to be those where the relationship to the patient was not that of a partner or spouse, more likely to have other caring responsibilities, and less likely to have friends or relations to call upon for help. Carers with unmet needs were also more likely to be in poor health themselves or to be caring for a patient who had reached the palliation-only phase in their cancer journey. The majority of carers expressed the importance of needs such as having good relationships with healthcare professionals and receiving honest information, but few expressed dissatisfaction with these aspects of need. Items of significant unmet need clustered around aspects of managing daily life, emotions, and also social identity for a sizeable minority of carers. These are the same areas of significant unmet need that concern patients. However, carers have more of these concerns, reflecting their comparative neglect. The paper also considers how these widespread concerns can be addressed.
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Affiliation(s)
- K Soothill
- Department of Applied Social Science, Institute for Health Research and Centre for Applied Statistics, Lancaster University, Lancaster LA1 4YL, UK.
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Soothill K, Morris SM, Harman J, Francis B, Thomas C, McIllmurray MB. The significant unmet needs of cancer patients: probing psychosocial concerns. Support Care Cancer 2001; 9:597-605. [PMID: 11762970 DOI: 10.1007/s005200100278] [Citation(s) in RCA: 137] [Impact Index Per Article: 6.0] [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: 10/27/2022]
Abstract
'Significant unmet needs' are those needs that patients identify as both important and unsatisfied. In this article we ask whether the overall needs of cancer patients are actually being met. We believe that the range of unmet need, and the kinds of patients who are more likely to claim unmet need, should be carefully identified. The needs responses of a series of 295 cancer patients in a cross-sectional survey were analysed. The majority expressed the opinion that information and good relationships with health care professionals were important, and few expressed dissatisfaction with these aspects of need. Similarly, needs items about support from family and friends were largely rated as important and satisfied. For a sizeable minority of patients, items of significant unmet need cluster around aspects of managing daily life, emotions, and social identity. The distribution of significant unmet needs is not random but is more likely to be experienced by patients who are younger, have a long-standing illness or disability, do not own/have use of a car, and/or have no religious faith. Furthermore, significant unmet needs relate to patients' ability to talk freely to a carer about the cancer, the degree to which the cancer interferes with social activities, and whether financial difficulties are experienced. Most of the significant unmet need is beyond the remit of services primarily designed for the treatment of disease. We consider whether multidisciplinary cancer teams can be expected to deal with all aspects of the cancer experience.
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Affiliation(s)
- K Soothill
- Department of Applied Social Science, Cartmel College, Lancaster University, UK.
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