1
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Rawal CC, Loubiere V, Butova NL, Gracia J, Parreno V, Merigliano C, Martinez AM, Cavalli G, Chiolo I. Sustained inactivation of the Polycomb PRC1 complex induces DNA repair defects and genomic instability in epigenetic tumors. Histochem Cell Biol 2024; 162:133-147. [PMID: 38888809 PMCID: PMC11227471 DOI: 10.1007/s00418-024-02302-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2024] [Indexed: 06/20/2024]
Abstract
Cancer initiation and progression are typically associated with the accumulation of driver mutations and genomic instability. However, recent studies demonstrated that cancer can also be driven purely by epigenetic alterations, without driver mutations. Specifically, a 24-h transient downregulation of polyhomeotic (ph-KD), a core component of the Polycomb complex PRC1, is sufficient to induce epigenetically initiated cancers (EICs) in Drosophila, which are proficient in DNA repair and characterized by a stable genome. Whether genomic instability eventually occurs when PRC1 downregulation is performed for extended periods of time remains unclear. Here, we show that prolonged depletion of PH, which mimics cancer initiating events, results in broad dysregulation of DNA replication and repair genes, along with the accumulation of DNA breaks, defective repair, and widespread genomic instability in the cancer tissue. A broad misregulation of H2AK118 ubiquitylation and to a lesser extent of H3K27 trimethylation also occurs and might contribute to these phenotypes. Together, this study supports a model where DNA repair and replication defects accumulate during the tumorigenic transformation epigenetically induced by PRC1 loss, resulting in genomic instability and cancer progression.
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Affiliation(s)
- Chetan C Rawal
- Department of Molecular and Computational Biology, University of Southern California, 1050 Childs Way, Los Angeles, CA, 90089, USA
| | - Vincent Loubiere
- Institute of Human Genetics, CNRS, University of Montpellier, Montpellier, France
- Research Institute of Molecular Pathology, Vienna BioCenter, Vienna, Austria
| | - Nadejda L Butova
- Department of Molecular and Computational Biology, University of Southern California, 1050 Childs Way, Los Angeles, CA, 90089, USA
| | - Juliette Gracia
- Institute of Human Genetics, CNRS, University of Montpellier, Montpellier, France
| | - Victoria Parreno
- Institute of Human Genetics, CNRS, University of Montpellier, Montpellier, France
| | - Chiara Merigliano
- Department of Molecular and Computational Biology, University of Southern California, 1050 Childs Way, Los Angeles, CA, 90089, USA
| | - Anne-Marie Martinez
- Institute of Human Genetics, CNRS, University of Montpellier, Montpellier, France.
| | - Giacomo Cavalli
- Institute of Human Genetics, CNRS, University of Montpellier, Montpellier, France.
| | - Irene Chiolo
- Department of Molecular and Computational Biology, University of Southern California, 1050 Childs Way, Los Angeles, CA, 90089, USA.
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2
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Atajanova T, Kang EM, Postnikova A, Price AL, Doerr S, Du M, Ugenti A, Ragkousi K. Lateral cell polarization drives organization of epithelia in sea anemone embryos and embryonic cell aggregates. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.07.588493. [PMID: 38645007 PMCID: PMC11030385 DOI: 10.1101/2024.04.07.588493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/23/2024]
Abstract
One of the first organizing processes during animal development is the assembly of embryonic cells into epithelia. In certain animals, including Hydra and sea anemones, epithelia also emerge when cells from dissociated tissues are aggregated back together. Although cell adhesion is required to keep cells together, it is not clear whether cell polarization plays a role as epithelia emerge from disordered aggregates. Here, we demonstrate that lateral cell polarization is essential for epithelial organization in both embryos and aggregates of the sea anemone Nematostella vectensis. Specifically, knock down of the lateral polarity protein Lgl disrupts epithelia in developing embryos and impairs the capacity of dissociated cells to epithelialize from aggregates. Cells in lgl mutant epithelia lose their columnar shape and have mispositioned mitotic spindles and ciliary basal bodies. Together, our data suggest that in Nematostella, Lgl is required to establish lateral cell polarity and position cytoskeletal organelles in cells of embryos and aggregates during de novo epithelial organization.
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Affiliation(s)
- Tavus Atajanova
- Department of Biology, Amherst College, Amherst, MA 01002, USA
- Present address: Dana-Farber Cancer Institute, Boston, MA 02215, USA
| | | | - Anna Postnikova
- Department of Biology, Amherst College, Amherst, MA 01002, USA
| | | | - Sophia Doerr
- Department of Biology, Amherst College, Amherst, MA 01002, USA
- Present address: Department of Biology, Institute of Molecular Biology, University of Oregon, Eugene, OR 97403, USA
| | - Michael Du
- Department of Biology, Amherst College, Amherst, MA 01002, USA
| | - Alicia Ugenti
- Department of Biology, Amherst College, Amherst, MA 01002, USA
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3
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Rabino A, Awadia S, Ali N, Edson A, Garcia-Mata R. The Scribble/SGEF/Dlg1 complex regulates the stability of apical junctions in epithelial cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.03.26.586884. [PMID: 38585765 PMCID: PMC10996629 DOI: 10.1101/2024.03.26.586884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
SGEF, a RhoG specific GEF, can form a ternary complex with the Scribble polarity complex proteins Scribble and Dlg1, which regulates the formation and maintenance of adherens junctions and barrier function of epithelial cells. Notably, silencing SGEF results in a dramatic downregulation of the expression of both E-cadherin and ZO-1. However, the molecular mechanisms involved in the regulation of this pathway are not known. Here, we describe a novel signaling pathway governed by the Scribble/SGEF/Dlg1 complex. Our results show that an intact ternary complex is required to maintain the stability of the apical junctions, the expression of ZO-1, and TJ permeability. In contrast, only SGEF is necessary to regulate E-cadherin expression. The absence of SGEF destabilizes the E-cadherin/catenin complex at the membrane, triggering a positive feedback loop that exacerbates the phenotype through the repression of E-cadherin transcription in a process that involves the internalization of E-cadherin by endocytosis, β-catenin signaling and the transcriptional repressor Slug.
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Affiliation(s)
- Agustin Rabino
- Department of Biological Sciences, University of Toledo, Toledo, OH, USA
| | - Sahezeel Awadia
- Department of Biological Sciences, University of Toledo, Toledo, OH, USA
| | - Nabaa Ali
- Department of Biological Sciences, University of Toledo, Toledo, OH, USA
| | - Amber Edson
- Department of Biological Sciences, University of Toledo, Toledo, OH, USA
| | - Rafael Garcia-Mata
- Department of Biological Sciences, University of Toledo, Toledo, OH, USA
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4
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Chen D, Lan X, Huang X, Huang J, Zhou X, Liu J, Hoffmann JA. mthl1, a potential Drosophila homologue of mammalian adhesion GPCRs, is involved in antitumor reactions to injected oncogenic cells in flies. Proc Natl Acad Sci U S A 2023; 120:e2303462120. [PMID: 37459549 PMCID: PMC10374174 DOI: 10.1073/pnas.2303462120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 05/18/2023] [Indexed: 07/20/2023] Open
Abstract
Injection of OCs into adult male flies induces a strong transcriptomic response in the host flies featuring in particular genes encoding bona fide G coupled proteins, among which the gene for methuselah like 1 is prominent. The injection is followed after a 3-d lag period, by the proliferation of the oncogenic cells. We hypothesized that through the product of mthl1 the host might control, at least in part, this proliferation as a defense reaction. Through a combination of genetic manipulations of the mthl1 gene (loss of function and overexpression of mthl1), we document that indeed this gene has an antiproliferative effect. Parallel injections of primary embryonic Drosophila cells or of various microbes do not exhibit this effect. We further show that mthl1 controls the expression of a large number of genes coding for chemoreceptors and genes implicated in regulation of development. Of great potential interest is our observation that the expression of the mouse gene coding for the adhesion G-protein-coupled receptor E1 (Adgre1, also known as F4/80), a potential mammalian homologue of mthl1, is significantly induced by B16-F10 melanoma cell inoculation 3 d postinjection in both the bone marrow and spleen (nests of immature and mature myeloid-derived immune cells), respectively. This observation is compatible with a role of this GPCR in the early response to injected tumor cells in mice.
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Affiliation(s)
- Di Chen
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou511436, China
| | - Xiao Lan
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou511436, China
| | - Xiaoming Huang
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou511436, China
| | - Jieqing Huang
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou511436, China
| | - Xiaojing Zhou
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou511436, China
| | - Jiyong Liu
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou511436, China
| | - Jules A. Hoffmann
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, Guangzhou511436, China
- University of StrasbourgInstitute for Advanced Study, 67000Strasbourg, France
- Institute of Molecular and Cellular Biology, CNRS, Insect Models of Innate Immunity (M3I; UPR9022), StrasbourgF-67084, France
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5
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Cell polarity and extrusion: How to polarize extrusion and extrude misspolarized cells? Curr Top Dev Biol 2023; 154:131-167. [PMID: 37100516 DOI: 10.1016/bs.ctdb.2023.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
Abstract
The barrier function of epithelia is one of the cornerstones of the body plan organization of metazoans. It relies on the polarity of epithelial cells which organizes along the apico-basal axis the mechanical properties, signaling as well as transport. This barrier function is however constantly challenged by the fast turnover of epithelia occurring during morphogenesis or adult tissue homeostasis. Yet, the sealing property of the tissue can be maintained thanks to cell extrusion: a series of remodeling steps involving the dying cell and its neighbors leading to seamless cell expulsion. Alternatively, the tissue architecture can also be challenged by local damages or the emergence of mutant cells that may alter its organization. This includes mutants of the polarity complexes which can generate neoplastic overgrowths or be eliminated by cell competition when surrounded by wild type cells. In this review, we will provide an overview of the regulation of cell extrusion in various tissues focusing on the relationship between cell polarity, cell organization and the direction of cell expulsion. We will then describe how local perturbations of polarity can also trigger cell elimination either by apoptosis or by cell exclusion, focusing specifically on how polarity defects can be directly causal to cell elimination. Overall, we propose a general framework connecting the influence of polarity on cell extrusion and its contribution to aberrant cell elimination.
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6
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Lv T, Xu J, Yuan H, Wang J, Jiang X. Dual Function of Par3 in Tumorigenesis. Front Oncol 2022; 12:915957. [PMID: 35875120 PMCID: PMC9305838 DOI: 10.3389/fonc.2022.915957] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2022] [Accepted: 06/14/2022] [Indexed: 11/20/2022] Open
Abstract
Cell maintenance and the establishment of cell polarity involve complicated interactions among multiple protein complexes as well as the regulation of different signaling pathways. As an important cell polarity protein, Par3 is evolutionarily conserved and involved in tight junction formation as well as tumorigenesis. In this review, we aimed to explore the function of Par3 in tumorigenesis. Research has shown that Par3 exhibits dual functions in human cancers, both tumor-promoting and tumor-suppressive. Here, we focus on the activities of Par3 in different stages and types of tumors, aiming to offer a new perspective on the molecular mechanisms that regulate the functions of Par3 in tumor development. Tumor origin, tumor microenvironment, tumor type, cell density, cell–cell contact, and the synergistic effect of Par3 and other tumor-associated signaling pathways may be important reasons for the dual function of Par3. The important role of Par3 in mammalian tumorigenesis and potential signaling pathways is context dependent.
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Affiliation(s)
- Tao Lv
- Centre for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, China
- Yunnan Engineering Research Center of Fruit Wine, Qujing Normal University, Qujing, China
- Key Laboratory of Yunnan Province Universities of Qujing Natural History and Early Vertebrate Evolution, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, China
| | - Jiashun Xu
- Centre for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, China
| | - Hemei Yuan
- Centre for Yunnan Plateau Biological Resources Protection and Utilization, College of Biological Resource and Food Engineering, Qujing Normal University, Qujing, China
| | - Jianling Wang
- College of Chemistry and Environmental Science, Qujing Normal University, Qujing, China
- *Correspondence: Jianling Wang, ; Xinni Jiang,
| | - Xinni Jiang
- School of Biological Sciences and Technology, Chengdu Medical College, Chengdu, China
- *Correspondence: Jianling Wang, ; Xinni Jiang,
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7
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A Blueprint for Cancer-Related Inflammation and Host Innate Immunity. Cells 2021; 10:cells10113211. [PMID: 34831432 PMCID: PMC8623541 DOI: 10.3390/cells10113211] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/27/2021] [Accepted: 11/10/2021] [Indexed: 12/30/2022] Open
Abstract
Both in situ and allograft models of cancer in juvenile and adult Drosophila melanogaster fruit flies offer a powerful means for unravelling cancer gene networks and cancer-host interactions. They can also be used as tools for cost-effective drug discovery and repurposing. Moreover, in situ modeling of emerging tumors makes it possible to address cancer initiating events-a black box in cancer research, tackle the innate antitumor immune responses to incipient preneoplastic cells and recurrent growing tumors, and decipher the initiation and evolution of inflammation. These studies in Drosophila melanogaster can serve as a blueprint for studies in more complex organisms and help in the design of mechanism-based therapies for the individualized treatment of cancer diseases in humans. This review focuses on new discoveries in Drosophila related to the diverse innate immune responses to cancer-related inflammation and the systemic effects that are so detrimental to the host.
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8
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Bilder D, Ong K, Hsi TC, Adiga K, Kim J. Tumour-host interactions through the lens of Drosophila. Nat Rev Cancer 2021; 21:687-700. [PMID: 34389815 PMCID: PMC8669834 DOI: 10.1038/s41568-021-00387-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/01/2021] [Indexed: 02/07/2023]
Abstract
There is a large gap between the deep understanding of mechanisms driving tumour growth and the reasons why patients ultimately die of cancer. It is now appreciated that interactions between the tumour and surrounding non-tumour (sometimes referred to as host) cells play critical roles in mortality as well as tumour progression, but much remains unknown about the underlying molecular mechanisms, especially those that act beyond the tumour microenvironment. Drosophila has a track record of high-impact discoveries about cell-autonomous growth regulation, and is well suited to now probe mysteries of tumour - host interactions. Here, we review current knowledge about how fly tumours interact with microenvironmental stroma, circulating innate immune cells and distant organs to influence disease progression. We also discuss reciprocal regulation between tumours and host physiology, with a particular focus on paraneoplasias. The fly's simplicity along with the ability to study lethality directly provide an opportunity to shed new light on how cancer actually kills.
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Affiliation(s)
- David Bilder
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA.
| | - Katy Ong
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Tsai-Ching Hsi
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Kavya Adiga
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
| | - Jung Kim
- Department of Molecular and Cell Biology, University of California, Berkeley, CA, USA
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9
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Riga A, Cravo J, Schmidt R, Pires HR, Castiglioni VG, van den Heuvel S, Boxem M. Caenorhabditis elegans LET-413 Scribble is essential in the epidermis for growth, viability, and directional outgrowth of epithelial seam cells. PLoS Genet 2021; 17:e1009856. [PMID: 34673778 PMCID: PMC8570498 DOI: 10.1371/journal.pgen.1009856] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 11/05/2021] [Accepted: 10/04/2021] [Indexed: 12/12/2022] Open
Abstract
The conserved adapter protein Scribble (Scrib) plays essential roles in a variety of cellular processes, including polarity establishment, proliferation, and directed cell migration. While the mechanisms through which Scrib promotes epithelial polarity are beginning to be unraveled, its roles in other cellular processes including cell migration remain enigmatic. In C. elegans, the Scrib ortholog LET-413 is essential for apical–basal polarization and junction formation in embryonic epithelia. However, whether LET-413 is required for postembryonic development or plays a role in migratory events is not known. Here, we use inducible protein degradation to investigate the functioning of LET-413 in larval epithelia. We find that LET-413 is essential in the epidermal epithelium for growth, viability, and junction maintenance. In addition, we identify a novel role for LET-413 in the polarized outgrowth of the epidermal seam cells. These stem cell-like epithelial cells extend anterior and posterior directed apical protrusions in each larval stage to reconnect to their neighbors. We show that the role of LET-413 in seam cell outgrowth is likely mediated largely by the junctional component DLG-1 discs large, which we demonstrate is also essential for directed outgrowth of the seam cells. Our data uncover multiple essential functions for LET-413 in larval development and show that the polarized outgrowth of the epithelial seam cells is controlled by LET-413 Scribble and DLG-1 Discs large. Most cells in multicellular organisms are organized along a directional axis of cell polarity. One protein that is important for this polarized organization is the conserved polarity regulator Scribble. This protein has several functions, including forming the basolateral domains of cells, promoting the formation of cell junctions, and promoting cell migration. How Scribble performs these functions is not fully understood. In this paper we study the role of Scribble during larval development of the small nematode Caenorhabditis elegans using an inducible protein degradation system. We show that Scribble, called LET-413 in C. elegans, is essential in the epidermal epithelium for animal development, as depletion of LET-413 in only this tissue blocks growth. We also demonstrate that LET-413 is required for the polarized outgrowth of an epithelial cell type called the seam cells, a process resembling cell migration. Finally, we show that one major function of LET-413 in seam cell outgrowth is the localization of the junctional component Discs large (DLG-1), which we demonstrate is also essential for this process. Our data thus uncover multiple essential functions for LET-413 in larval development and provide new insights into how the directional outgrowth of epithelial seam cells is controlled.
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Affiliation(s)
- Amalia Riga
- Division of Developmental Biology, Institute of Biodynamics and Biocomplexity, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Janine Cravo
- Division of Developmental Biology, Institute of Biodynamics and Biocomplexity, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Ruben Schmidt
- Division of Developmental Biology, Institute of Biodynamics and Biocomplexity, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Helena R. Pires
- Division of Developmental Biology, Institute of Biodynamics and Biocomplexity, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Victoria G. Castiglioni
- Division of Developmental Biology, Institute of Biodynamics and Biocomplexity, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Sander van den Heuvel
- Division of Developmental Biology, Institute of Biodynamics and Biocomplexity, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
| | - Mike Boxem
- Division of Developmental Biology, Institute of Biodynamics and Biocomplexity, Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
- * E-mail:
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10
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Lavictoire SJ, Jomaa D, Gont A, Jardine K, Cook DP, Lorimer IAJ. Identification of Rac guanine nucleotide exchange factors promoting Lgl1 phosphorylation in glioblastoma. J Biol Chem 2021; 297:101172. [PMID: 34624316 PMCID: PMC8551657 DOI: 10.1016/j.jbc.2021.101172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 08/25/2021] [Accepted: 09/03/2021] [Indexed: 11/23/2022] Open
Abstract
The protein Lgl1 is a key regulator of cell polarity. We previously showed that Lgl1 is inactivated by hyperphosphorylation in glioblastoma as a consequence of PTEN tumour suppressor loss and aberrant activation of the PI 3-kinase pathway; this contributes to glioblastoma pathogenesis both by promoting invasion and repressing glioblastoma cell differentiation. Lgl1 is phosphorylated by atypical protein kinase C that has been activated by binding to a complex of the scaffolding protein Par6 and active, GTP-bound Rac. The specific Rac guanine nucleotide exchange factors that generate active Rac to promote Lgl1 hyperphosphorylation in glioblastoma are unknown. We used CRISPR/Cas9 to knockout PREX1, a PI 3-kinase pathway-responsive Rac guanine nucleotide exchange factor, in patient-derived glioblastoma cells. Knockout cells had reduced Lgl1 phosphorylation, which was reversed by re-expressing PREX1. They also had reduced motility and an altered phenotype suggestive of partial neuronal differentiation; consistent with this, RNA-seq analyses identified sets of PREX1-regulated genes associated with cell motility and neuronal differentiation. PREX1 knockout in glioblastoma cells from a second patient did not affect Lgl1 phosphorylation. This was due to overexpression of a short isoform of the Rac guanine nucleotide exchange factor TIAM1; knockdown of TIAM1 in these PREX1 knockout cells reduced Lgl1 phosphorylation. These data show that PREX1 links aberrant PI 3-kinase signaling to Lgl1 phosphorylation in glioblastoma, but that TIAM1 is also to fill this role in a subset of patients. This redundancy between PREX1 and TIAM1 is only partial, as motility was impaired in PREX1 knockout cells from both patients.
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Affiliation(s)
- Sylvie J Lavictoire
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - Danny Jomaa
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada; School of Medicine, Faculty of Health Sciences, Queen's University, Kingston, Ontario, Canada
| | - Alexander Gont
- Cell Biology Program, The Hospital for Sick Children, Toronto, Ontario, Canada
| | - Karen Jardine
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada
| | - David P Cook
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, Ontario, Canada
| | - Ian A J Lorimer
- Cancer Therapeutics Program, Ottawa Hospital Research Institute, Ottawa, Ontario, Canada; Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada; Department of Medicine, University of Ottawa, Ottawa, Ontario, Canada.
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11
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Barbet V, Broutier L. Future Match Making: When Pediatric Oncology Meets Organoid Technology. Front Cell Dev Biol 2021; 9:674219. [PMID: 34327198 PMCID: PMC8315550 DOI: 10.3389/fcell.2021.674219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 05/10/2021] [Indexed: 11/13/2022] Open
Abstract
Unlike adult cancers that frequently result from the accumulation in time of mutational “hits” often linked to lifestyle, childhood cancers are emerging as diseases of dysregulated development through massive epigenetic alterations. The ability to reconstruct these differences in cancer models is therefore crucial for better understanding the uniqueness of pediatric cancer biology. Cancer organoids (i.e., tumoroids) represent a promising approach for creating patient-derived in vitro cancer models that closely recapitulate the overall pathophysiological features of natural tumorigenesis, including intra-tumoral heterogeneity and plasticity. Though largely applied to adult cancers, this technology is scarcely used for childhood cancers, with a notable delay in technological transfer. However, tumoroids could provide an unprecedented tool to unravel the biology of pediatric cancers and improve their therapeutic management. We herein present the current state-of-the-art of a long awaited and much needed matchmaking.
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Affiliation(s)
- Virginie Barbet
- Childhood Cancer & Cell Death (C3), Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Centre de Recherche en Cancérologie de Lyon (CRCL), Lyon, France
| | - Laura Broutier
- Childhood Cancer & Cell Death (C3), Université Claude Bernard Lyon 1, INSERM 1052, CNRS 5286, Centre Léon Bérard, Centre de Recherche en Cancérologie de Lyon (CRCL), Lyon, France
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12
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Chen D, Roychowdhury-Sinha A, Prakash P, Lan X, Fan W, Goto A, Hoffmann JA. A time course transcriptomic analysis of host and injected oncogenic cells reveals new aspects of Drosophila immune defenses. Proc Natl Acad Sci U S A 2021; 118:e2100825118. [PMID: 33737397 PMCID: PMC8000351 DOI: 10.1073/pnas.2100825118] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Oncogenic RasV12 cells [A. Simcox et al., PLoS Genet 4, e1000142 (2008)] injected into adult males proliferated massively after a lag period of several days, and led to the demise of the flies after 2 to 3 wk. The injection induced an early massive transcriptomic response that, unexpectedly, included more than 100 genes encoding chemoreceptors of various families. The kinetics of induction and the identities of the induced genes differed markedly from the responses generated by injections of microbes. Subsequently, hundreds of genes were up-regulated, attesting to intense catabolic activities in the flies, active tracheogenesis, and cuticulogenesis, as well as stress and inflammation-type responses. At 11 d after the injections, GFP-positive oncogenic cells isolated from the host flies exhibited a markedly different transcriptomic profile from that of the host and distinct from that at the time of their injection, including in particular up-regulated expression of genes typical for cells engaged in the classical antimicrobial response of Drosophila.
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Affiliation(s)
- Di Chen
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, 511436 Guangzhou, China;
- Insect Models of Innate Immunity (M3I; UPR9022), CNRS, University of Strasbourg, F-67084 Strasbourg, France
| | | | - Pragya Prakash
- Insect Models of Innate Immunity (M3I; UPR9022), CNRS, University of Strasbourg, F-67084 Strasbourg, France
| | - Xiao Lan
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, 511436 Guangzhou, China
| | - Wenmin Fan
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, 511436 Guangzhou, China
| | - Akira Goto
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, 511436 Guangzhou, China;
- Insect Models of Innate Immunity (M3I; UPR9022), CNRS, University of Strasbourg, F-67084 Strasbourg, France
| | - Jules A Hoffmann
- Sino-French Hoffmann Institute, School of Basic Medical Science, Guangzhou Medical University, 511436 Guangzhou, China;
- Insect Models of Innate Immunity (M3I; UPR9022), CNRS, University of Strasbourg, F-67084 Strasbourg, France
- University of Strasbourg Institute for Advanced Study, 67000 Strasbourg, France
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13
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Jonckheere S, Adams J, De Groote D, Campbell K, Berx G, Goossens S. Epithelial-Mesenchymal Transition (EMT) as a Therapeutic Target. Cells Tissues Organs 2021; 211:157-182. [PMID: 33401271 DOI: 10.1159/000512218] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 10/11/2020] [Indexed: 11/19/2022] Open
Abstract
Metastasis is the spread of cancer cells from the primary tumour to distant sites and organs throughout the body. It is the primary cause of cancer morbidity and mortality, and is estimated to account for 90% of cancer-related deaths. During the initial steps of the metastatic cascade, epithelial cancer cells undergo an epithelial-mesenchymal transition (EMT), and as a result become migratory and invasive mesenchymal-like cells while acquiring cancer stem cell properties and therapy resistance. As EMT is involved in such a broad range of processes associated with malignant transformation, it has become an increasingly interesting target for the development of novel therapeutic strategies. Anti-EMT therapeutic strategies could potentially not only prevent the invasion and dissemination of cancer cells, and as such prevent the formation of metastatic lesions, but also attenuate cancer stemness and increase the effectiveness of more classical chemotherapeutics. In this review, we give an overview about the pros and cons of therapies targeting EMT and discuss some already existing candidate drug targets and high-throughput screening tools to identify novel anti-EMT compounds.
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Affiliation(s)
- Sven Jonckheere
- Cancer Research Institute Ghent (CRIG), Ghent University, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Jamie Adams
- Department of Biomedical Science, The University of Sheffield, Sheffield, United Kingdom
| | - Dominic De Groote
- Cancer Research Institute Ghent (CRIG), Ghent University, Ghent, Belgium
| | - Kyra Campbell
- Department of Biomedical Science, The University of Sheffield, Sheffield, United Kingdom
| | - Geert Berx
- Cancer Research Institute Ghent (CRIG), Ghent University, Ghent, Belgium.,Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
| | - Steven Goossens
- Cancer Research Institute Ghent (CRIG), Ghent University, Ghent, Belgium, .,Department of Diagnostic Sciences, Ghent University, Ghent, Belgium,
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14
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Gut bacteria-derived peptidoglycan induces a metabolic syndrome-like phenotype via NF-κB-dependent insulin/PI3K signaling reduction in Drosophila renal system. Sci Rep 2020; 10:14097. [PMID: 32839462 PMCID: PMC7445169 DOI: 10.1038/s41598-020-70455-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 07/13/2020] [Indexed: 12/17/2022] Open
Abstract
Although microbiome-host interactions are usual at steady state, gut microbiota dysbiosis can unbalance the physiological and behavioral parameters of the host, mostly via yet not understood mechanisms. Using the Drosophila model, we investigated the consequences of a gut chronic dysbiosis on the host physiology. Our results show that adult flies chronically infected with the non-pathogenic Erwinia carotorova caotovora bacteria displayed organ degeneration resembling wasting-like phenotypes reminiscent of Metabolic Syndrome associated pathologies. Genetic manipulations demonstrate that a local reduction of insulin signaling consecutive to a peptidoglycan-dependent NF-κB activation in the excretory system of the flies is responsible for several of the observed phenotypes. This work establishes a functional crosstalk between bacteria-derived peptidoglycan and the immune NF-κB cascade that contributes to the onset of metabolic disorders by reducing insulin signal transduction. Giving the high degree of evolutionary conservation of the mechanisms and pathways involved, this study is likely to provide a helpful model to elucidate the contribution of altered intestinal microbiota in triggering human chronic kidney diseases.
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15
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Schmidt A, Peifer M. Scribble and Dlg organize a protection racket to ensure apical-basal polarity. Proc Natl Acad Sci U S A 2020; 117:13188-13190. [PMID: 32471949 PMCID: PMC7306729 DOI: 10.1073/pnas.2007739117] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Affiliation(s)
- Anja Schmidt
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
| | - Mark Peifer
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599;
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599
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16
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Biehler C, Wang LT, Sévigny M, Jetté A, Gamblin CL, Catterall R, Houssin E, McCaffrey L, Laprise P. Girdin is a component of the lateral polarity protein network restricting cell dissemination. PLoS Genet 2020; 16:e1008674. [PMID: 32196494 PMCID: PMC7112241 DOI: 10.1371/journal.pgen.1008674] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2019] [Revised: 04/01/2020] [Accepted: 02/14/2020] [Indexed: 01/07/2023] Open
Abstract
Epithelial cell polarity defects support cancer progression. It is thus crucial to decipher the functional interactions within the polarity protein network. Here we show that Drosophila Girdin and its human ortholog (GIRDIN) sustain the function of crucial lateral polarity proteins by inhibiting the apical kinase aPKC. Loss of GIRDIN expression is also associated with overgrowth of disorganized cell cysts. Moreover, we observed cell dissemination from GIRDIN knockdown cysts and tumorspheres, thereby showing that GIRDIN supports the cohesion of multicellular epithelial structures. Consistent with these observations, alteration of GIRDIN expression is associated with poor overall survival in subtypes of breast and lung cancers. Overall, we discovered a core mechanism contributing to epithelial cell polarization from flies to humans. Our data also indicate that GIRDIN has the potential to impair the progression of epithelial cancers by preserving cell polarity and restricting cell dissemination.
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Affiliation(s)
- Cornélia Biehler
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada
- axe oncologie du Centre de Recherche du Centre Hospitalier, Universitaire de Québec-UL, Québec, Canada
| | - Li-Ting Wang
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Canada
| | - Myriam Sévigny
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada
- axe oncologie du Centre de Recherche du Centre Hospitalier, Universitaire de Québec-UL, Québec, Canada
| | - Alexandra Jetté
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada
- axe oncologie du Centre de Recherche du Centre Hospitalier, Universitaire de Québec-UL, Québec, Canada
| | - Clémence L. Gamblin
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada
- axe oncologie du Centre de Recherche du Centre Hospitalier, Universitaire de Québec-UL, Québec, Canada
| | - Rachel Catterall
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Canada
| | - Elise Houssin
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada
- axe oncologie du Centre de Recherche du Centre Hospitalier, Universitaire de Québec-UL, Québec, Canada
| | - Luke McCaffrey
- Rosalind and Morris Goodman Cancer Research Centre, McGill University, Montreal, Canada
- Gerald Bronfman Department of Oncology, McGill University, Montreal, Canada
| | - Patrick Laprise
- Centre de Recherche sur le Cancer, Université Laval, Québec, Canada
- axe oncologie du Centre de Recherche du Centre Hospitalier, Universitaire de Québec-UL, Québec, Canada
- * E-mail:
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17
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Bonello TT, Choi W, Peifer M. Scribble and Discs-large direct initial assembly and positioning of adherens junctions during the establishment of apical-basal polarity. Development 2019; 146:dev.180976. [PMID: 31628110 DOI: 10.1242/dev.180976] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 10/14/2019] [Indexed: 01/05/2023]
Abstract
Apical-basal polarity is a fundamental property of animal tissues. Drosophila embryos provide an outstanding model for defining mechanisms that initiate and maintain polarity. Polarity is initiated during cellularization, when cell-cell adherens junctions are positioned at the future boundary of apical and basolateral domains. Polarity maintenance then involves complementary and antagonistic interplay between apical and basal polarity complexes. The Scribble/Dlg module is well-known for promoting basolateral identity during polarity maintenance. Here, we report a surprising role for Scribble/Dlg in polarity initiation, placing it near the top of the network-positioning adherens junctions. Scribble and Dlg are enriched in nascent adherens junctions, are essential for adherens junction positioning and supermolecular assembly, and also play a role in basal junction assembly. We test the hypotheses for the underlying mechanisms, exploring potential effects on protein trafficking, cytoskeletal polarity or Par-1 localization/function. Our data suggest that the Scribble/Dlg module plays multiple roles in polarity initiation. Different domains of Scribble contribute to these distinct roles. Together, these data reveal novel roles for Scribble/Dlg as master scaffolds regulating assembly of distinct junctional complexes at different times and places.
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Affiliation(s)
- Teresa T Bonello
- Department of Biology, University of North Carolina at Chapel Hill, CB#3280, Chapel Hill, NC 27599-3280, USA
| | - Wangsun Choi
- Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Mark Peifer
- Department of Biology, University of North Carolina at Chapel Hill, CB#3280, Chapel Hill, NC 27599-3280, USA .,Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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18
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Link N, Chung H, Jolly A, Withers M, Tepe B, Arenkiel BR, Shah PS, Krogan NJ, Aydin H, Geckinli BB, Tos T, Isikay S, Tuysuz B, Mochida GH, Thomas AX, Clark RD, Mirzaa GM, Lupski JR, Bellen HJ. Mutations in ANKLE2, a ZIKA Virus Target, Disrupt an Asymmetric Cell Division Pathway in Drosophila Neuroblasts to Cause Microcephaly. Dev Cell 2019; 51:713-729.e6. [PMID: 31735666 DOI: 10.1016/j.devcel.2019.10.009] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 08/19/2019] [Accepted: 10/14/2019] [Indexed: 12/12/2022]
Abstract
The apical Par complex, which contains atypical protein kinase C (aPKC), Bazooka (Par-3), and Par-6, is required for establishing polarity during asymmetric division of neuroblasts in Drosophila, and its activity depends on L(2)gl. We show that loss of Ankle2, a protein associated with microcephaly in humans and known to interact with Zika protein NS4A, reduces brain volume in flies and impacts the function of the Par complex. Reducing Ankle2 levels disrupts endoplasmic reticulum (ER) and nuclear envelope morphology, releasing the kinase Ballchen-VRK1 into the cytosol. These defects are associated with reduced phosphorylation of aPKC, disruption of Par-complex localization, and spindle alignment defects. Importantly, removal of one copy of ballchen or l(2)gl suppresses Ankle2 mutant phenotypes and restores viability and brain size. Human mutational studies implicate the above-mentioned genes in microcephaly and motor neuron disease. We suggest that NS4A, ANKLE2, VRK1, and LLGL1 define a pathway impinging on asymmetric determinants of neural stem cell division.
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Affiliation(s)
- Nichole Link
- Howard Hughes Medical Institute, BCM, Houston, TX 77030, USA; Department of Molecular and Human Genetics, BCM, Houston, TX 77030, USA; Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Hyunglok Chung
- Howard Hughes Medical Institute, BCM, Houston, TX 77030, USA; Department of Molecular and Human Genetics, BCM, Houston, TX 77030, USA; Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA
| | - Angad Jolly
- Department of Molecular and Human Genetics, BCM, Houston, TX 77030, USA; MD/PhD Medical Scientist Training Program and MHG Graduate program, BCM, Houston, TX 77030, USA
| | - Marjorie Withers
- Department of Molecular and Human Genetics, BCM, Houston, TX 77030, USA
| | - Burak Tepe
- Department of Molecular and Human Genetics, BCM, Houston, TX 77030, USA; Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Program in Developmental Biology, BCM, Houston, TX 77030, USA
| | - Benjamin R Arenkiel
- Department of Molecular and Human Genetics, BCM, Houston, TX 77030, USA; Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; Program in Developmental Biology, BCM, Houston, TX 77030, USA
| | - Priya S Shah
- Department of Chemical Engineering and Department of Microbiology and Molecular Genetics, University of California, Davis, Davis, CA 95616, USA
| | - Nevan J Krogan
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, San Francisco, CA 94158, USA; California Institute for Quantitative Biosciences, QB3, University of California, San Francisco, San Francisco, CA 94158, USA
| | - Hatip Aydin
- Center of Genetics Diagnosis, Zeynep Kamil Maternity and Children's Training and Research Hospital, Istanbul, Turkey
| | - Bilgen B Geckinli
- Department of Medical Genetics, Marmara University School of Medicine, Istanbul, Turkey
| | - Tulay Tos
- Department of Medical Genetics, Dr. Sami Ulus Research and Training Hospital of Women's and Children's Health and Diseases, Ankara, Turkey
| | - Sedat Isikay
- Department of Physiotherapy and Rehabilitation, Hasan Kalyoncu University, School of Health Sciences, Gaziantep, Turkey
| | - Beyhan Tuysuz
- Department of Pediatrics, Istanbul University-Cerrahpasa, Medical Faculty, Istanbul, Turkey
| | - Ganesh H Mochida
- Division of Genetics and Genomics, Department of Pediatrics and Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA 02115, USA; Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA; Pediatric Neurology Unit, Department of Neurology, Massachusetts General Hospital, Boston, MA 02114, USA
| | - Ajay X Thomas
- Department of Pediatrics, Section of Neurology and Developmental Neuroscience, BCM, Houston, TX 77030, USA; Section of Child Neurology, Texas Children's Hospital, Houston, TX 77030, USA
| | - Robin D Clark
- Division of Medical Genetics, Department of Pediatrics, Loma Linda University Medical Center, Loma Linda, CA 92354, USA
| | - Ghayda M Mirzaa
- Department of Pediatrics, University of Washington, Seattle, WA 98195, USA; Center for Integrative Brain Research, Seattle Children's Research Institute, Seattle, WA 98105, USA
| | - James R Lupski
- Department of Molecular and Human Genetics, BCM, Houston, TX 77030, USA; Department of Pediatrics, BCM, Houston, TX 77030, USA; Texas Children's Hospital, Houston, TX 77030, USA; Human Genome Sequencing Center, Baylor College of Medicine, Houston, TX 77030, USA
| | - Hugo J Bellen
- Howard Hughes Medical Institute, BCM, Houston, TX 77030, USA; Department of Molecular and Human Genetics, BCM, Houston, TX 77030, USA; Neurological Research Institute, Texas Children's Hospital, Houston, TX 77030, USA; MD/PhD Medical Scientist Training Program and MHG Graduate program, BCM, Houston, TX 77030, USA; Program in Developmental Biology, BCM, Houston, TX 77030, USA.
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19
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Domingos PM, Jenny A, Combie KF, Del Alamo D, Mlodzik M, Steller H, Mollereau B. Regulation of Numb during planar cell polarity establishment in the Drosophila eye. Mech Dev 2019; 160:103583. [PMID: 31678471 DOI: 10.1016/j.mod.2019.103583] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Revised: 10/17/2019] [Accepted: 10/29/2019] [Indexed: 01/15/2023]
Abstract
The establishment of planar cell polarity (PCP) in the Drosophila eye requires correct specification of the R3/R4 pair of photoreceptor cells, determined by a Frizzled mediated signaling event that specifies R3 and induces Delta to activate Notch signaling in the neighboring cell, specifying it as R4. Here, we investigated the role of the Notch signaling negative regulator Numb in the specification of R3/R4 fates and PCP establishment in the Drosophila eye. We observed that Numb is transiently upregulated in R3 at the time of R3/R4 specification. This regulation of Numb levels in developing photoreceptors occurs at the post-transcriptional level and is dependent on Dishevelled, an effector of Frizzled signaling, and Lethal Giant Larva. We detected PCP defects in cells homozygous for numb15, but these defects were due to a loss of function mutation in fat (fatQ805⁎) being present in the numb15 chromosome. However, mosaic overexpression of Numb in R4 precursors (only) caused PCP defects and numb loss-of-function alleles had a modifying effect on the defects found in a hypomorphic dishevelled mutation. Our results suggest that Numb levels are upregulated to reinforce the bias of Notch signaling activation in the R3/R4 pair, two post-mitotic cells that are not specified by asymmetric cell division.
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Affiliation(s)
- Pedro M Domingos
- Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, Oeiras 2780-157, Portugal; Strang Laboratory of Apoptosis and Cancer Research, The Rockefeller University, Box 252, 1230 York Avenue, New York, NY 10065, USA.
| | - Andreas Jenny
- Albert Einstein College of Medicine, 1300 Morris Park Avenue, Chanin Building, Room 503, Bronx NY10461, USA; Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Keon F Combie
- Strang Laboratory of Apoptosis and Cancer Research, The Rockefeller University, Box 252, 1230 York Avenue, New York, NY 10065, USA
| | - David Del Alamo
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA; European Molecular Biology Organization, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Marek Mlodzik
- Department of Cell, Developmental, and Regenerative Biology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10029, USA
| | - Hermann Steller
- Strang Laboratory of Apoptosis and Cancer Research, The Rockefeller University, Box 252, 1230 York Avenue, New York, NY 10065, USA
| | - Bertrand Mollereau
- Strang Laboratory of Apoptosis and Cancer Research, The Rockefeller University, Box 252, 1230 York Avenue, New York, NY 10065, USA; Université de Lyon, ENSL, UCBL, CNRS, LBMC, 46 Allée d'Italie, 69007 Lyon, France.
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20
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Awadia S, Huq F, Arnold TR, Goicoechea SM, Sun YJ, Hou T, Kreider-Letterman G, Massimi P, Banks L, Fuentes EJ, Miller AL, Garcia-Mata R. SGEF forms a complex with Scribble and Dlg1 and regulates epithelial junctions and contractility. J Cell Biol 2019; 218:2699-2725. [PMID: 31248911 PMCID: PMC6683736 DOI: 10.1083/jcb.201811114] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 03/18/2019] [Accepted: 04/12/2019] [Indexed: 01/15/2023] Open
Abstract
The canonical Scribble polarity complex is implicated in regulation of epithelial junctions and apical polarity. Here, we show that SGEF, a RhoG-specific GEF, forms a ternary complex with Scribble and Dlg1, two members of the Scribble complex. SGEF targets to apical junctions in a Scribble-dependent fashion and functions in the regulation of actomyosin-based contractility and barrier function at tight junctions as well as E-cadherin-mediated formation of adherens junctions. Surprisingly, SGEF does not control the establishment of polarity. However, in 3D cysts, SGEF regulates the formation of a single open lumen. Interestingly, SGEF's nucleotide exchange activity regulates the formation and maintenance of adherens junctions, and in cysts the number of lumens formed, whereas SGEF's scaffolding activity is critical for regulation of actomyosin contractility and lumen opening. We propose that SGEF plays a key role in coordinating junctional assembly and actomyosin contractility by bringing together Scribble and Dlg1 and targeting RhoG activation to cell-cell junctions.
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Affiliation(s)
- Sahezeel Awadia
- Department of Biological Sciences, The University of Toledo, Toledo, OH
| | - Farah Huq
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | - Torey R Arnold
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
| | | | - Young Joo Sun
- Department of Biochemistry, University of Iowa, Iowa City, IA
| | - Titus Hou
- Department of Biochemistry, University of Iowa, Iowa City, IA
| | | | - Paola Massimi
- International Center for Genetic Engineering and Biotechnology, Trieste, Italy
| | - Lawrence Banks
- International Center for Genetic Engineering and Biotechnology, Trieste, Italy
| | | | - Ann L Miller
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI
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21
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Villegas SN. One hundred years of Drosophila cancer research: no longer in solitude. Dis Model Mech 2019; 12:12/4/dmm039032. [PMID: 30952627 PMCID: PMC6505481 DOI: 10.1242/dmm.039032] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 03/12/2019] [Indexed: 12/28/2022] Open
Abstract
When Mary Stark first described the presence of tumours in the fruit fly Drosophila melanogaster in 1918, would she ever have imagined that flies would become an invaluable organism for modelling and understanding oncogenesis? And if so, would she have expected it to take 100 years for this model to be fully accredited? This Special Article summarises the efforts and achievements of Drosophilists to establish the fly as a valid model in cancer research through different scientific periods.
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Affiliation(s)
- Santiago Nahuel Villegas
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas (CSIC) and Universidad Miguel Hernandez (UMH), Campus de Sant Joan, Apartado 18, 03550 Sant Joan, Alicante, Spain
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22
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Wu P, Wu F, Yan S, Liu C, Shen Z, Xiong X, Li Z, Zhang Q, Liu X. Developmental cost of leg-regenerated Coccinella septempunctata (Coleoptera: Coccinellidae). PLoS One 2019; 14:e0210615. [PMID: 30657777 PMCID: PMC6338371 DOI: 10.1371/journal.pone.0210615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 12/30/2018] [Indexed: 11/18/2022] Open
Abstract
As larval cannibalism is common under intensive rearing conditions, leg regeneration can help ladybugs adapt to the competitive environment, but whether the leg regeneration leads to side effects on development remains unclear. To analyze the potentially developmental cost of leg regeneration, the developmental period and weight of leg-regenerated Coccinella septempunctata were studied in the laboratory. The results showed that, when the time intervals between the emergency of 4th-instar larva and leg amputation increased, the developmental period of leg-regenerated 4th-instar larvae was gradually prolonged. Significantly developmental delay were also examined at prepupal and pupal stages, and various timings of leg amputation affected the periods of leg-regenerated prepupae/pupae similarly. After the leg was amputated at different larval instars, the developmental delay only occurred at the larval instar when the leg was amputated, whereas other larval instars failed to be extended, and the developmental periods of leg-regenerated prepupae/pupae were affected similarly by the instars of leg amputation. Developmental delays possibly resulted in more consumption by leg-regenerated larvae, and then weight gains at prepupal/pupal stages, but different larval instars of leg amputation affected the weight gain similarly. Both the developmental delay (at 4th-instar larval, prepupal and pupal stages) and weight gain (at pupal and adult stages) in complete/bilateral amputation were longer or greater than those in half/unilateral amputation. However, the thoracic locations of leg amputation impacted the developmental delay and weight gain similarly. Our study indicates that although leg regeneration triggers the developmental cost decreasing the competitive superiority or agility, C. septempunctata larvae still choose to completely regenerate the leg to adapt to complex environments. Thus, in order to remain competitive at adult stages, leg-impaired larvae may make an investment tradeoff between leg regeneration and developmental cost.
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Affiliation(s)
- Pengxiang Wu
- Department of Entomology, China Agricultural University, Beijing, China
| | - Fengming Wu
- Department of Entomology, China Agricultural University, Beijing, China
| | - Shuo Yan
- Department of Entomology, China Agricultural University, Beijing, China
| | - Chang Liu
- Entomology and Nematology Department, University of Florida, Gainesville, FL, United States of America
| | - Zhongjian Shen
- Department of Entomology, China Agricultural University, Beijing, China
| | - Xiaofei Xiong
- Department of Entomology, China Agricultural University, Beijing, China
| | - Zhen Li
- Department of Entomology, China Agricultural University, Beijing, China
| | - Qingwen Zhang
- Department of Entomology, China Agricultural University, Beijing, China
| | - Xiaoxia Liu
- Department of Entomology, China Agricultural University, Beijing, China
- * E-mail:
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23
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Bonello TT, Peifer M. Scribble: A master scaffold in polarity, adhesion, synaptogenesis, and proliferation. J Cell Biol 2018; 218:742-756. [PMID: 30598480 PMCID: PMC6400555 DOI: 10.1083/jcb.201810103] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 11/26/2018] [Accepted: 12/14/2018] [Indexed: 02/08/2023] Open
Abstract
Key events ranging from cell polarity to proliferation regulation to neuronal signaling rely on the assembly of multiprotein adhesion or signaling complexes at particular subcellular sites. Multidomain scaffolding proteins nucleate assembly and direct localization of these complexes, and the protein Scribble and its relatives in the LAP protein family provide a paradigm for this. Scribble was originally identified because of its role in apical-basal polarity and epithelial integrity in Drosophila melanogaster It is now clear that Scribble acts to assemble and position diverse multiprotein complexes in processes ranging from planar polarity to adhesion to oriented cell division to synaptogenesis. Here, we explore what we have learned about the mechanisms of action of Scribble in the context of its multiple known interacting partners and discuss how this knowledge opens new questions about the full range of Scribble protein partners and their structural and signaling roles.
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Affiliation(s)
- Teresa T Bonello
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC
| | - Mark Peifer
- Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC .,Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC.,Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC
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24
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Using Mouse and Drosophila Models to Investigate the Mechanistic Links between Diet, Obesity, Type II Diabetes, and Cancer. Int J Mol Sci 2018; 19:ijms19124110. [PMID: 30567377 PMCID: PMC6320797 DOI: 10.3390/ijms19124110] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 12/12/2018] [Accepted: 12/14/2018] [Indexed: 02/06/2023] Open
Abstract
Many of the links between diet and cancer are controversial and over simplified. To date, human epidemiological studies consistently reveal that patients who suffer diet-related obesity and/or type II diabetes have an increased risk of cancer, suffer more aggressive cancers, and respond poorly to current therapies. However, the underlying molecular mechanisms that increase cancer risk and decrease the response to cancer therapies in these patients remain largely unknown. Here, we review studies in mouse cancer models in which either dietary or genetic manipulation has been used to model obesity and/or type II diabetes. These studies demonstrate an emerging role for the conserved insulin and insulin-like growth factor signaling pathways as links between diet and cancer progression. However, these models are time consuming to develop and expensive to maintain. As the world faces an epidemic of obesity and type II diabetes we argue that the development of novel animal models is urgently required. We make the case for Drosophila as providing an unparalleled opportunity to combine dietary manipulation with models of human metabolic disease and cancer. Thus, combining diet and cancer models in Drosophila can rapidly and significantly advance our understanding of the conserved molecular mechanisms that link diet and diet-related metabolic disorders to poor cancer patient prognosis.
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Carmena A. Compromising asymmetric stem cell division in Drosophila central brain: Revisiting the connections with tumorigenesis. Fly (Austin) 2018; 12:71-80. [PMID: 29239688 DOI: 10.1080/19336934.2017.1416277] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Asymmetric cell division (ACD) is an essential process during development for generating cell diversity. In addition, a more recent connection between ACD, cancer and stem cell biology has opened novel and highly intriguing venues in the field. This connection between compromised ACD and tumorigenesis was first demonstrated using Drosophila neural stem cells (neuroblasts, NBs) more than a decade ago and, over the past years, it has also been established in vertebrate stem cells. Here, focusing on Drosophila larval brain NBs, and in light of results recently obtained in our lab, we revisit this connection emphasizing two main aspects: 1) the differences in tumor suppressor activity of different ACD regulators and 2) the potential relevance of environment and temporal window frame for compromised ACD-dependent induction of tumor-like overgrowth.
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Affiliation(s)
- Ana Carmena
- a Departamento de Neurobiología del Desarrollo , Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas/Universidad Miguel Hernández, Sant Joan d'Alacant , Alicante , Spain
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26
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Kwon Y, Song W, Droujinine IA, Hu Y, Asara JM, Perrimon N. Systemic organ wasting induced by localized expression of the secreted insulin/IGF antagonist ImpL2. Dev Cell 2015; 33:36-46. [PMID: 25850671 DOI: 10.1016/j.devcel.2015.02.012] [Citation(s) in RCA: 176] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Revised: 12/17/2014] [Accepted: 02/11/2015] [Indexed: 12/31/2022]
Abstract
Organ wasting, related to changes in nutrition and metabolic activity of cells and tissues, is observed under conditions of starvation and in the context of diseases, including cancers. We have developed a model for organ wasting in adult Drosophila, whereby overproliferation induced by activation of Yorkie, the Yap1 oncogene ortholog, in intestinal stem cells leads to wasting of the ovary, fat body, and muscle. These organ-wasting phenotypes are associated with a reduction in systemic insulin/IGF signaling due to increased expression of the secreted insulin/IGF antagonist ImpL2 from the overproliferating gut. Strikingly, expression of rate-limiting glycolytic enzymes and central components of the insulin/IGF pathway is upregulated with activation of Yorkie in the gut, which may provide a mechanism for this overproliferating tissue to evade the effect of ImpL2. Altogether, our study provides insights into the mechanisms underlying organ-wasting phenotypes in Drosophila and how overproliferating tissues adapt to global changes in metabolism.
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Affiliation(s)
- Young Kwon
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA.
| | - Wei Song
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Ilia A Droujinine
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - Yanhui Hu
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | - John M Asara
- Department of Medicine, Harvard Medical School, Boston, MA 02115, USA; Division of Signal Transduction, Beth Israel Deaconess Medical Center, Boston, MA 02115, USA
| | - Norbert Perrimon
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA; Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115, USA.
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Abstract
In insects, localized tissue injury often leads to global (organism-wide) delays in development and retarded metamorphosis. In Drosophila, for example, injuries to the larval imaginal discs can retard pupariation and prolong metamorphosis. Injuries induced by treatments such as radiation, mechanical damage and induction of localized cell death can trigger similar delays. In most cases, the duration of the developmental delay appears to be correlated with the extent of damage, but the effect is also sensitive to the developmental stage of the treated animal. The proximate cause of the delays is likely a disruption of the ecdysone signaling pathway, but the intermediate steps leading from tissue injury and/or regeneration to that disruption remain unknown. Here, we review the evidence for injury-induced developmental delays, and for a checkpoint or checkpoints associated with the temporal progression of development and the on-going efforts to define the mechanisms involved.
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Affiliation(s)
- Jennifer F Hackney
- a School of Mathematical and Natural Sciences; Arizona State University ; Phoenix , AZ USA
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28
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Guyer RA, Macara IG. Loss of the polarity protein PAR3 activates STAT3 signaling via an atypical protein kinase C (aPKC)/NF-κB/interleukin-6 (IL-6) axis in mouse mammary cells. J Biol Chem 2015; 290:8457-68. [PMID: 25657002 DOI: 10.1074/jbc.m114.621011] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
PAR3 suppresses tumor growth and metastasis in vivo and cell invasion through matrix in vitro. We propose that PAR3 organizes and limits multiple signaling pathways and that inappropriate activation of these pathways occurs without PAR3. Silencing Pard3 in conjunction with oncogenic activation promotes invasion and metastasis via constitutive STAT3 activity in mouse models, but the mechanism for this is unknown. We now show that loss of PAR3 triggers increased production of interleukin-6, which induces STAT3 signaling in an autocrine manner. Activation of atypical protein kinase C ι/λ (aPKCι/λ) mediates this effect by stimulating NF-κB signaling and IL-6 expression. Our results suggest that PAR3 restrains aPKCι/λ activity and thus prevents aPKCι/λ from activating an oncogenic signaling network.
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Affiliation(s)
- Richard A Guyer
- From the Department of Cell and Developmental Biology and Medical-Scientist Training Program, Vanderbilt University, Nashville, Tennessee 37232
| | - Ian G Macara
- From the Department of Cell and Developmental Biology and
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29
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lgl Regulates the Hippo Pathway Independently of Fat/Dachs, Kibra/Expanded/Merlin and dRASSF/dSTRIPAK. Cancers (Basel) 2014; 6:879-96. [PMID: 24743776 PMCID: PMC4074808 DOI: 10.3390/cancers6020879] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 03/12/2014] [Accepted: 03/25/2014] [Indexed: 01/15/2023] Open
Abstract
In both Drosophila and mammalian systems, the Hippo (Hpo) signalling pathway controls tissue growth by inhibiting cell proliferation and promoting apoptosis. The core pathway consists of a protein kinase Hpo (MST1/2 in mammals) that is regulated by a number of upstream inputs including Drosophila Ras Association Factor, dRASSF. We have previously shown in the developing Drosophila eye epithelium that loss of the apico-basal cell polarity regulator lethal-(2)-giant-larvae (lgl), and the concomitant increase in aPKC activity, results in ectopic proliferation and suppression of developmental cell death by blocking Hpo pathway signalling. Here, we further explore how Lgl/aPKC interacts with the Hpo pathway. Deregulation of the Hpo pathway by Lgl depletion is associated with the mislocalization of Hpo and dRASSF. We demonstrate that Lgl/aPKC regulate the Hpo pathway independently of upstream inputs from Fat/Dachs and the Kibra/Expanded/Merlin complex. We show depletion of Lgl also results in accumulation and mislocalization of components of the dSTRIPAK complex, a major phosphatase complex that directly binds to dRASSF and represses Hpo activity. However, depleting dSTRIPAK components, or removal of dRASSF did not rescue the lgl−/− or aPKC overexpression phenotypes. Thus, Lgl/aPKC regulate Hpo activity by a novel mechanism, independently of dRASSF and dSTRIPAK. Surprisingly, removal of dRASSF in tissue with increased aPKC activity results in mild tissue overgrowth, indicating that in this context dRASSF acts as a tumor suppressor. This effect was independent of the Hpo and Ras Mitogen Activated Protein Kinase (MAPK) pathways, suggesting that dRASSF regulates a novel pathway to control tissue growth.
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Common variants of Drosophila melanogaster Cyp6d2 cause camptothecin sensitivity and synergize with loss of Brca2. G3-GENES GENOMES GENETICS 2013; 3:91-9. [PMID: 23316441 PMCID: PMC3538347 DOI: 10.1534/g3.112.003996] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 11/07/2012] [Indexed: 11/18/2022]
Abstract
Many chemotherapeutic agents selectively target rapidly dividing cells, including cancer cells, by causing DNA damage that leads to genome instability and cell death. We used Drosophila melanogaster to study how mutations in key DNA repair genes affect an organism's response to chemotherapeutic drugs. In this study, we focused on camptothecin and its derivatives, topotecan and irinotecan, which are type I topoisomerase inhibitors that create DNA double-strand breaks in rapidly dividing cells. Here, we describe two polymorphisms in Drosophila Cyp6d2 that result in extreme sensitivity to camptothecin but not topotecan or irinotecan. We confirmed that the sensitivity was due to mutations in Cyp6d2 by rescuing the defect with a wild-type copy of Cyp6d2. In addition, we showed that combining a cyp6d2 mutation with mutations in Drosophila brca2 results in extreme sensitivity to camptothecin. Given the frequency of the Cyp6d2 polymorphisms in publcly available Drosophila stocks, our study demonstrates the need for caution when interpreting results from drug sensitivity screens in Drosophila and other model organisms. Furthermore, our findings illustrate how genetic background effects can be important when determining the efficacy of chemotherapeutic agents in various DNA repair mutants.
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31
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The Scribble-Dlg-Lgl polarity module in development and cancer: from flies to man. Essays Biochem 2012; 53:141-68. [PMID: 22928514 DOI: 10.1042/bse0530141] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The Scribble, Par and Crumbs modules were originally identified in the vinegar (fruit) fly, Drosophila melanogaster, as being critical regulators of apico-basal cell polarity. In the present chapter we focus on the Scribble polarity module, composed of Scribble, discs large and lethal giant larvae. Since the discovery of the role of the Scribble polarity module in apico-basal cell polarity, these proteins have also been recognized as having important roles in other forms of polarity, as well as regulation of the actin cytoskeleton, cell signalling and vesicular trafficking. In addition to these physiological roles, an important role for polarity proteins in cancer progression has also been uncovered, with loss of polarity and tissue architecture being strongly correlated with metastatic disease.
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32
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Kaplan NA, Tolwinski NS. Spatially defined Dsh-Lgl interaction contributes to directional tissue morphogenesis. J Cell Sci 2010; 123:3157-65. [PMID: 20736316 DOI: 10.1242/jcs.069898] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The process of epithelial morphogenesis defines the structure of epidermal tissue sheets. One such sheet, the ventral epidermis of the Drosophila embryo, shows both intricate segmental patterning and complex cell organization. Within a segment, cells produce hair-like denticles in a stereotypical and highly organized pattern over the surface of the tissue. To understand the cell biological basis of this process, we examined cell shapes and alignments, and looked for molecules that showed an asymmetric distribution in this tissue. We found that apical polarity determinants and adherens junctions were enriched at the dorsal and ventral borders of cells, whereas basolateral determinants were enriched at the anterior and posterior borders. We report that the basolateral determinant Lgl has a novel function in the planar organization of the embryonic epidermis, and this function depends on Dsh and myosin. We conclude that apical-basal proteins, used to establish polarity within a cell, can be independently co-opted to function in epithelial morphogenesis.
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Affiliation(s)
- Nicole A Kaplan
- Program in Developmental Biology, Sloan-Kettering Institute, Memorial Sloan-Kettering Cancer Center, 1275 York Avenue, Box 423, New York, NY 10021, USA
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33
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Grzeschik NA, Parsons LM, Allott ML, Harvey KF, Richardson HE. Lgl, aPKC, and Crumbs Regulate the Salvador/Warts/Hippo Pathway through Two Distinct Mechanisms. Curr Biol 2010; 20:573-81. [DOI: 10.1016/j.cub.2010.01.055] [Citation(s) in RCA: 287] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2009] [Revised: 01/22/2010] [Accepted: 01/26/2010] [Indexed: 01/15/2023]
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34
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Reischauer S, Levesque MP, Nüsslein-Volhard C, Sonawane M. Lgl2 executes its function as a tumor suppressor by regulating ErbB signaling in the zebrafish epidermis. PLoS Genet 2009; 5:e1000720. [PMID: 19911055 PMCID: PMC2771016 DOI: 10.1371/journal.pgen.1000720] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2009] [Accepted: 10/15/2009] [Indexed: 12/18/2022] Open
Abstract
Changes in tissue homeostasis, acquisition of invasive cell characteristics, and tumor formation can often be linked to the loss of epithelial cell polarity. In carcinogenesis, the grade of neoplasia correlates with impaired cell polarity. In Drosophila, lethal giant larvae (lgl), discs large (dlg), and scribble, which are components of the epithelial apico-basal cell polarity machinery, act as tumor suppressors, and orthologs of this evolutionary conserved pathway are lost in human carcinoma with high frequency. However, a mechanistic link between neoplasia and vertebrate orthologs of these tumor-suppressor genes remains to be fully explored at the organismal level. Here, we show that the pen/lgl2 mutant phenotype shares two key cellular and molecular features of mammalian malignancy: cell autonomous epidermal neoplasia and epithelial-to-mesenchymal-transition (EMT) of basal epidermal cells including the differential expression of several regulators of EMT. Further, we found that epidermal neoplasia and EMT in pen/lgl2 mutant epidermal cells is promoted by ErbB signalling, a pathway of high significance in human carcinomas. Intriguingly, EMT in the pen/lgl2 mutant is facilitated specifically by ErbB2 mediated E-cadherin mislocalization and not via canonical snail-dependent down-regulation of E-cadherin expression. Our data reveal that pen/lgl2 functions as a tumor suppressor gene in vertebrates, establishing zebrafish pen/lgl2 mutants as a valuable cancer model.
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Affiliation(s)
- Sven Reischauer
- Max-Planck Institut für Entwicklungsbiologie, Department of Genetics, Tuebingen, Germany
| | - Mitchell P. Levesque
- Max-Planck Institut für Entwicklungsbiologie, Department of Genetics, Tuebingen, Germany
| | | | - Mahendra Sonawane
- Max-Planck Institut für Entwicklungsbiologie, Department of Genetics, Tuebingen, Germany
- * E-mail:
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35
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Abstract
Epithelial polarity is established and maintained by competition between determinants that define the apical and basolateral domains. Cell-cell adhesion complexes, or adherens junctions, form at the interface of these regions. Mutations in adhesion components as well as apical determinants normally lead to an expansion of the basolateral domain. Here we investigate the genetic relationship between the polarity determinants and adhesion and show that the levels of the adhesion protein Armadillo affect competition. We find that in arm mutants, even a modest reduction in the basolateral component lgl leads to a full apical domain expansion or lgl phenotype. By using an allelic series of Armadillo mutations, we show that there is a threshold at which basolateral expansion can be reversed. Further, in embryos lacking the Wingless signaling component zw3, the same full apical expansion occurs again with only a reduction in lgl. We propose a model where zw3 regulates protein levels of apical and adhesion components and suggest that a reciprocal interaction between junctions and polarity modules functions to maintain stable apical and basolateral domains.
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36
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Rhiner C, Díaz B, Portela M, Poyatos JF, Fernández-Ruiz I, López-Gay JM, Gerlitz O, Moreno E. Persistent competition among stem cells and their daughters in the Drosophila ovary germline niche. Development 2009; 136:995-1006. [PMID: 19211674 DOI: 10.1242/dev.033340] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Cell competition is a short-range cell-cell interaction leading to the proliferation of winner cells at the expense of losers, although either cell type shows normal growth in homotypic environments. Drosophila Myc (dMyc; Dm-FlyBase) is a potent inducer of cell competition in wing epithelia, but its role in the ovary germline stem cell niche is unknown. Here, we show that germline stem cells (GSCs) with relative lower levels of dMyc are replaced by GSCs with higher levels of dMyc. By contrast, dMyc-overexpressing GSCs outcompete wild-type stem cells without affecting total stem cell numbers. We also provide evidence for a naturally occurring cell competition border formed by high dMyc-expressing stem cells and low dMyc-expressing progeny, which may facilitate the concentration of the niche-provided self-renewal factor BMP/Dpp in metabolically active high dMyc stem cells. Genetic manipulations that impose uniform dMyc levels across the germline produce an extended Dpp signaling domain and cause uncoordinated differentiation events. We propose that dMyc-induced competition plays a dual role in regulating optimal stem cell pools and sharp differentiation boundaries, but is potentially harmful in the case of emerging dmyc duplications that facilitate niche occupancy by pre-cancerous stem cells. Moreover, competitive interactions among stem cells may be relevant for the successful application of stem cell therapies in humans.
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37
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Abstract
The neoplastic tumour suppressors, Scribble, Dlg and Lgl, originally discovered in the vinegar fly Drosophila melanogaster, are currently being actively studied for their potential role in mammalian tumourigenesis. In Drosophila, these tumour suppressors function in a common genetic pathway to regulate apicobasal cell polarity and also play important roles in the control of cell proliferation, survival, differentiation and in cell migration/invasion. The precise mechanism by which Scribble, Dlg and Lgl function is not clear; however, they have been implicated in the regulation of signalling pathways, vesicle trafficking and in the Myosin II-actin cytoskeleton. We review the evidence for the involvement of Scribble, Dlg, and Lgl in cancer, and how the various functions ascribed to these tumour suppressors in Drosophila and mammalian systems may impact on the process of tumourigenesis.
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38
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Mechler BM, Török I, Schmidt M, Opper M, Kuhn A, Merz R, Protin U. Molecular basis for the regulation of cell fate by the lethal (2) giant larvae tumour suppressor gene of Drosophila melanogaster. CIBA FOUNDATION SYMPOSIUM 2007; 142:166-78; discussion 178-80. [PMID: 2545420 DOI: 10.1002/9780470513750.ch11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Tumour suppressor genes act as recessive determinants of cancer. Their function is required for normal cell growth and differentiation during development. When both alleles of these developmental genes are inactivated, cell growth becomes unrestricted. In Drosophila, a series of genes have been identified which when mutated produce tissue-specific tumours. Of these the lethal(2)giant larvae (l(2)gl) gene is the best studied. Homozygous l(2)gl mutations cause the development of malignant tumours in the brain and the imaginal discs. Genomic DNA from the l(2)gl locus has been cloned, introduced back into l(2)gl mutant animals by P-element-mediated transformation and shown to restore normal development. The nucleotide sequence of the l(2)gl gene (13.1 kb) has been determined, as well as the sequences of the two classes of transcripts. These transcripts encode two polypeptides of 127 kDa and 78 kDa, respectively. Both proteins have been immunologically identified. Analyses of the spatial distribution of both l(2)gl transcripts and proteins revealed that during early embryogenesis the l(2)gl gene is uniformly expressed in all cells and tissues. In late embryos, the l(2)gl expression becomes gradually restricted to tissues presenting no morphological or neoplastic alteration in the mutant animals. Further mosaic experiments pointed out that the critical period for the establishment of tumorigenesis is limited to early embryogenesis at a time when the l(2)gl expression is most intense in all cells.
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Affiliation(s)
- B M Mechler
- Institute of Genetics, Johannes Gutenberg University, Mainz, Federal Republic of Germany
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39
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Gonzalez C. Spindle orientation, asymmetric division and tumour suppression in Drosophila stem cells. Nat Rev Genet 2007; 8:462-72. [PMID: 17510666 DOI: 10.1038/nrg2103] [Citation(s) in RCA: 156] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Recent genetic studies in flies have added further support to an increasing body of evidence that suggests that stem cells might be the cell-of-origin of certain tumours. Malfunction of the mechanisms that control the division of stem cells and the developmental fate of the two resulting daughters could be one of the initial events that steers cells into malignant transformation. These studies suggest a role for controlled spindle orientation in suppressing stem-cell overgrowth. In parallel, the machinery that drives asymmetry in stem cells has been further characterized, identifying new components and uncovering the unique, highly sophisticated behaviour of centrosomes in these cells.
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Affiliation(s)
- Cayetano Gonzalez
- Cell Division Group, Institute for Research in Biomedicine, Barcelona, Spain.
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40
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Abstract
Inactivating mutations in the Drosophila tumor-suppressor genes result in tissue overgrowth. This can occur because the mutant tissue either grows faster than wild-type tissue and/or continues to grow beyond a time when wild-type tissue stops growing. There are three general classes of tumor-suppressor genes that regulate the growth of imaginal disc epithelia. Mutations in the hyperplastic tumor-suppressor genes result in increased cell proliferation but do not disrupt normal tissue architecture. These genes include pten, Tsc1, Tsc2, and components of the hippo/salvador/warts pathway. Mutations in a second class of genes, the neoplastic tumor-suppressor genes, disrupt proteins that function either as scaffolds at cell-cell junctions (scribble, discs large, lgl) or as components of the endocytic pathway (avalanche, rab5, ESCRT components). For the third group, the nonautonomous tumor-suppressor genes, mutant cells stimulate the proliferation of adjacent wild-type cells. Understanding the interactions between these three classes of genes will improve our understanding of how cell and tissue growth are coordinated during organismal development and perturbed in disease states such as cancer.
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Affiliation(s)
- Iswar K Hariharan
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, California 94720, USA.
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41
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Abstract
Cell competition is a homeostatic mechanism that regulates the size attained by growing tissues. We performed an unbiased genetic screen for mutations that permit the survival of cells being competed due to haplo-insufficiency for RpL36. Mutations that protect RpL36 heterozygous clones include the tumor suppressors expanded, hippo, salvador, mats, and warts, which are members of the Warts pathway, the tumor suppressor fat, and a novel tumor-suppressor mutation. Other hyperplastic or neoplastic mutations did not rescue RpL36 heterozygous clones. Most mutations that rescue cell competition elevated Dpp-signaling activity, and the Dsmurf mutation that elevates Dpp signaling was also hyperplastic and rescued. Two nonlethal, nonhyperplastic mutations prevent the apoptosis of Minute heterozygous cells and suggest an apoptosis pathway for cell competition . In addition to rescuing RpL36 heterozygous cells, mutations in Warts pathway genes were supercompetitors that could eliminate wild-type cells nearby. The findings show that differences in Warts pathway activity can lead to competition and implicate the Warts pathway, certain other tumor suppressors, and novel cell death components in cell competition, in addition to the Dpp pathway implicated by previous studies. We suggest that cell competition might occur during tumor development in mammals.
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Affiliation(s)
- David M Tyler
- Department of Molecular Genetics, Albert Einstein College of Medicine, Bronx, New York 10461, USA
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42
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Beaucher M, Goodliffe J, Hersperger E, Trunova S, Frydman H, Shearn A. Drosophila brain tumor metastases express both neuronal and glial cell type markers. Dev Biol 2006; 301:287-97. [PMID: 17055475 PMCID: PMC1859848 DOI: 10.1016/j.ydbio.2006.09.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2006] [Revised: 08/29/2006] [Accepted: 09/08/2006] [Indexed: 12/23/2022]
Abstract
Loss of either lgl or brat gene activity in Drosophila larvae causes neoplastic brain tumors. Fragments of tumorous brains from either mutant transplanted into adult hosts over-proliferate, and kill their hosts within 2 weeks. We developed an in vivo assay for the metastatic potential of tumor cells by quantifying micrometastasis formation within the ovarioles of adult hosts after transplantation and determined that specific metastatic properties of lgl and brat tumor cells are different. We detected micrometastases in 15.8% of ovarioles from wild type host females 12 days after transplanting lgl tumor cells into their abdominal cavities. This frequency increased significantly with increased proliferation time. We detected micrometastases in 15% of ovarioles from wild type host females 10 days after transplanting brat tumor cells into their abdominal cavities. By contrast, this frequency did not change significantly with increased proliferation time. We found that nearly all lgl micrometastases co-express the neuronal cell marker, ELAV, and the glial cell marker, REPO. These markers are not co-expressed in normal brain cells nor in tumorous brain cells. This indicates deregulated gene expression in these metastatic cells. By contrast, most of the brat micrometastases expressed neither marker. While mutations in both lgl and brat cause neoplastic brain tumors, our results reveal that metastatic cells arising from these tumors have quite different properties. These data may have important implications for the treatment of tumor metastasis.
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Affiliation(s)
- Michelle Beaucher
- Department of Biology, The Johns Hopkins University, Baltimore, MD 21218, USA
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43
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Lee CY, Robinson KJ, Doe CQ. Lgl, Pins and aPKC regulate neuroblast self-renewal versus differentiation. Nature 2005; 439:594-8. [PMID: 16357871 DOI: 10.1038/nature04299] [Citation(s) in RCA: 255] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2005] [Accepted: 10/03/2005] [Indexed: 11/08/2022]
Abstract
How a cell chooses to proliferate or to differentiate is an important issue in stem cell and cancer biology. Drosophila neuroblasts undergo self-renewal with every cell division, producing another neuroblast and a differentiating daughter cell, but the mechanisms controlling the self-renewal/differentiation decision are poorly understood. Here we tested whether cell polarity genes, known to regulate embryonic neuroblast asymmetric cell division, also regulate neuroblast self-renewal. Clonal analysis in larval brains showed that pins mutant neuroblasts rapidly fail to self-renew, whereas lethal giant larvae (lgl) mutant neuroblasts generate multiple neuroblasts. Notably, lgl pins double mutant neuroblasts all divide symmetrically to self-renew, filling the brain with neuroblasts at the expense of neurons. The lgl pins neuroblasts show ectopic cortical localization of atypical protein kinase C (aPKC), and a decrease in aPKC expression reduces neuroblast numbers, suggesting that aPKC promotes neuroblast self-renewal. In support of this hypothesis, neuroblast-specific overexpression of membrane-targeted aPKC, but not a kinase-dead version, induces ectopic neuroblast self-renewal. We conclude that cortical aPKC kinase activity is a potent inducer of neuroblast self-renewal.
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Affiliation(s)
- Cheng-Yu Lee
- Institutes of Neuroscience and Molecular Biology, Howard Hughes Medical Institute, University of Oregon 1254, Eugene, Oregon 97403, USA
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44
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Caussinus E, Gonzalez C. Induction of tumor growth by altered stem-cell asymmetric division in Drosophila melanogaster. Nat Genet 2005; 37:1125-9. [PMID: 16142234 DOI: 10.1038/ng1632] [Citation(s) in RCA: 333] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2005] [Accepted: 07/11/2005] [Indexed: 11/09/2022]
Abstract
Loss of cell polarity and cancer are tightly correlated, but proof for a causative relationship has remained elusive. In stem cells, loss of polarity and impairment of asymmetric cell division could alter cell fates and thereby render daughter cells unable to respond to the mechanisms that control proliferation. To test this hypothesis, we generated Drosophila melanogaster larval neuroblasts containing mutations in various genes that control asymmetric cell division and then assayed their proliferative potential after transplantation into adult hosts. We found that larval brain tissue carrying neuroblasts with mutations in raps (also called pins), mira, numb or pros grew to more than 100 times their initial size, invading other tissues and killing the hosts in 2 weeks. These tumors became immortal and could be retransplanted into new hosts for years. Six weeks after the first implantation, genome instability and centrosome alterations, two traits of malignant carcinomas, appeared in these tumors. Increasing evidence suggests that some tumors may be of stem cell origin. Our results show that loss of function of any of several genes that control the fate of a stem cell's daughters may result in hyperproliferation, triggering a chain of events that subverts cell homeostasis in a general sense and leads to cancer.
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Affiliation(s)
- Emmanuel Caussinus
- Cell Biology and Biophysics Program, European Molecular Biology Laboratory, Meyerhofstrasse 1, 69117 Heidelberg, Germany
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45
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Rabinow L. The proliferation of Drosophila in cancer research: a system for the functional characterization of tumor suppressors and oncogenes. Cancer Invest 2002; 20:531-56. [PMID: 12094549 DOI: 10.1081/cnv-120002154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- Leonard Rabinow
- Laboratoire de Signalisation, Développement et Cancer, CNRS UPRES-A 8080, Bâtiment 445, Université de Paris XI, 91405 Orsay, France.
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Nedelcheva M, Topouzova T, Genova G. Transcription of Dfos is stimulated by brain tumours of l(2)gl-deficient larvae of Drosophila melanogaster. Int J Biochem Cell Biol 2001; 33:45-51. [PMID: 11167131 DOI: 10.1016/s1357-2725(00)00071-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Mutations in the tumour suppressor gene l(2)gl cause formation of brain and imaginal disc tumours. The product of this gene was suggested to be a part of an intercellular communication system, regulating cell growth and differentiation. Oncogenic activation of many signalling pathways, involved in similar processes, result in increased activity of the AP-1 family of transcription factors. In this paper we explored the interaction between the cancer mutation l(2)gl and the level of transcription of the AP-1 proteins. We report that in brain tumours from l(2)gl-deficient larvae, transcription of the Drosophila melanogaster c-fos homologue was stimulated but that of the c-jun homologue was unchanged. Our results provide further evidence that the protein l(2)gl is a component of a signalling pathway, a nuclear target of which is the AP-1 family of transcription factors.
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Affiliation(s)
- M Nedelcheva
- Department of Genetics, Faculty of Biology, University of Sofia, 8 Dragan Tsankov Str., 1421 Sofia, Bulgaria
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47
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Arama E, Dickman D, Kimchie Z, Shearn A, Lev Z. Mutations in the beta-propeller domain of the Drosophila brain tumor (brat) protein induce neoplasm in the larval brain. Oncogene 2000; 19:3706-16. [PMID: 10949924 DOI: 10.1038/sj.onc.1203706] [Citation(s) in RCA: 103] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Inactivation of both alleles of the fruit fly D. melanogaster brain tumor (brat) gene results in the production of a tumor-like neoplasm in the larval brain, and lethality in the larval third instar and pupal stages. We cloned the brat gene from a transposon-tagged allele and identified its gene product. brat encodes for an 1037 amino acid protein with an N-terminal B-boxl zinc finger followed by a B-box2 zinc finger, a coiled-coil domain, and a C-terminal beta-propeller domain with six blades. All these motifs are known to mediate protein-protein interactions. Sequence analysis of four brat alleles revealed that all of them are mutated at the beta-propeller domain. The clustering of mutations in this domain strongly suggests that it has a crucial role in the normal function of Brat, and defines a novel protein motif involved in tumor suppression activity. The brat gene is expressed in the embryonic central and peripheral nervous systems including the embryonic brain. In third instar larva brat expression was detected in the larval central nervous system including the brain and the ventral ganglion, in two glands - the ring gland and the salivary gland, and in parts of the foregut - the gastric caecae and the proventriculus. A second brat-like gene was found in D. melanogaster, and homologs were identified in the nematode, mouse, rat, and human. Accumulated data suggests that Brat may regulate proliferation and differentiation by secretion/transport-mediated processes.
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Affiliation(s)
- E Arama
- Department of Biology, Technion-Israel Institute of Technology, Haifa
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48
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Abstract
All animal cells have a polarity, that is, different proteins are clustered in distinct domains of the plasma membrane and these regions carry out different jobs. As Peifer discusses in a lively Perspective, new work (Bilder et al.) identifies some of the molecular characters that direct proteins to their different cellular destinations.
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Affiliation(s)
- M Peifer
- Department of Biology and Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3280, USA.
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49
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Farkas R, Mechler BM. The timing of drosophila salivary gland apoptosis displays an l(2)gl-dose response. Cell Death Differ 2000; 7:89-101. [PMID: 10713724 DOI: 10.1038/sj.cdd.4400621] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
During Drosophila metamorphosis, larval tissues, such as the salivary glands, are histolysed whereas imaginal tissues differentiate into adult structures forming at eclosion a fly-shaped adult. Inactivation of the lethal(2)giant larvae (l(2)gl) gene encoding the cytoskeletal associated p127 protein, causes malignant transformation of brain neuroblasts and imaginal disc cells with developmental arrest at the larval-pupal transition phase. At this stage, p127 is expressed in wild-type salivary glands which become fully histolysed 12 - 13 h after pupariation. By contrast to wild-type, administration of 20-hydroxyecdsone to l(2)gl-deficient salivary glands is unable to induce histolysis, although it releases stored glue granules and gives rise to a nearly normal pupariation chromosome puffing, indicating that p127 is required for salivary gland apoptosis. To unravel the l(2)gl function in this tissue we used transgenic lines expressing reduced ( approximately 0.1) or increased levels of p127 (3.0). Here we show that the timing of salivary gland histolysis displays an l(2)gl-dose response. Reduced p127 expression delays histolysis whereas overexpression accelerates this process without affecting the duration of third larval instar, prepupal and pupal development. Similar l(2)gl-dependence is noticed in the timing of expression of the cell death genes reaper, head involution defective and grim, supporting the idea that p127 plays a critical role in the implementation of ecdysone-triggered apoptosis. These experiments show also that the timing of salivary gland apoptosis can be manipulated without affecting normal development and provide ways to investigate the nature of the components specifically involved in the apoptotic pathway of the salivary glands.
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Affiliation(s)
- R Farkas
- Department of Developmental Genetics, Deutsches Krebsforschungszentrum, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany
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50
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Baek KH. Application of temperature-sensitive mutations to oncogene studies in Drosophila. Arch Pharm Res 1999; 22:229-31. [PMID: 10403122 DOI: 10.1007/bf02976354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Recessive oncogenes are genetic functions important in the regulation of tissue growth and differentiation. These genetic functions are defined on the basis of the phenotype expressed by homozygotes. Defining the role of these genes in normal developmental and physiological processes is important to the development of accurate models of the normal regulation of growth and differentiation. Drosophila can be a good system to investigate the neoplastic mechanism of oncogenes and provide a greater understanding in the developmental progression of both invertebrates and vertebrates. The lethal (2) giant larvae gene is a recessive oncogene of Drosophila and temperature sensitive mutations of this gene have been isolated. Here, the application of temperature-sensitive mutations in Drosophila oncogene studies is discussed.
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Affiliation(s)
- K H Baek
- Division of Pediatric Oncology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.
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