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Day JL, Tirard M, Brose N. Deletion of a core APC/C component reveals APC/C function in regulating neuronal USP1 levels and morphology. Front Mol Neurosci 2024; 17:1352782. [PMID: 38932933 PMCID: PMC11199872 DOI: 10.3389/fnmol.2024.1352782] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2023] [Accepted: 03/14/2024] [Indexed: 06/28/2024] Open
Abstract
Introduction The Anaphase Promoting Complex (APC/C), an E3 ubiquitin ligase, plays a key role in cell cycle control, but it is also thought to operate in postmitotic neurons. Most studies linking APC/C function to neuron biology employed perturbations of the APC/C activators, cell division cycle protein 20 (Cdc20) and Cdc20 homologue 1 (Cdh1). However, multiple lines of evidence indicate that Cdh1 and Cdc20 can function in APC/C-independent contexts, so that the effects of their perturbation cannot strictly be linked to APC/C function. Methods We therefore deleted the gene encoding Anaphase Promoting Complex 4 (APC4), a core APC/C component, in neurons cultured from conditional knockout (cKO) mice. Results Our data indicate that several previously published substrates are actually not APC/C substrates, whereas ubiquitin specific peptidase 1 (USP1) protein levels are altered in APC4 knockout (KO) neurons. We propose a model where the APC/C ubiquitylates USP1 early in development, but later ubiquitylates a substrate that directly or indirectly stabilizes USP1. We further discovered a novel role of the APC/C in regulating the number of neurites exiting somata, but we were unable to confirm prior data indicating that the APC/C regulates neurite length, neurite complexity, and synaptogenesis. Finally, we show that APC4 SUMOylation does not impact the ability of the APC/C to control the number of primary neurites or USP1 protein levels. Discussion Our data indicate that perturbation studies aimed at dissecting APC/C biology must focus on core APC/C components rather than the APC/C activators, Cdh20 and Cdh1.
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Affiliation(s)
| | | | - Nils Brose
- Department of Molecular Neurobiology, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
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Advani D, Kumar P. Uncovering Cell Cycle Dysregulations and Associated Mechanisms in Cancer and Neurodegenerative Disorders: A Glimpse of Hope for Repurposed Drugs. Mol Neurobiol 2024:10.1007/s12035-024-04130-7. [PMID: 38532240 DOI: 10.1007/s12035-024-04130-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2023] [Accepted: 03/19/2024] [Indexed: 03/28/2024]
Abstract
The cell cycle is the sequence of events orchestrated by a complex network of cell cycle proteins. Unlike normal cells, mature neurons subsist in a quiescent state of the cell cycle, and aberrant cell cycle activation triggers neuronal death accompanied by neurodegeneration. The periodicity of cell cycle events is choreographed by various mechanisms, including DNA damage repair, oxidative stress, neurotrophin activity, and ubiquitin-mediated degradation. Given the relevance of cell cycle processes in cancer and neurodegeneration, this review delineates the overlapping cell cycle events, signaling pathways, and mechanisms associated with cell cycle aberrations in cancer and the major neurodegenerative disorders. We suggest that dysregulation of some common fundamental signaling processes triggers anomalous cell cycle activation in cancer cells and neurons. We discussed the possible use of cell cycle inhibitors for neurodegenerative disorders and described the associated challenges. We propose that a greater understanding of the common mechanisms driving cell cycle aberrations in cancer and neurodegenerative disorders will open a new avenue for the development of repurposed drugs.
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Affiliation(s)
- Dia Advani
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly Delhi College of Engineering), Shahbad Daulatpur, Bawana Road, New Delhi, Delhi, 110042, India
| | - Pravir Kumar
- Molecular Neuroscience and Functional Genomics Laboratory, Department of Biotechnology, Delhi Technological University (Formerly Delhi College of Engineering), Shahbad Daulatpur, Bawana Road, New Delhi, Delhi, 110042, India.
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3
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Biswas L, Schindler K. Predicting Infertility: How Genetic Variants in Oocyte Spindle Genes Affect Egg Quality. ADVANCES IN ANATOMY, EMBRYOLOGY, AND CELL BIOLOGY 2024; 238:1-22. [PMID: 39030352 DOI: 10.1007/978-3-031-55163-5_1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/21/2024]
Abstract
Successful reproduction relies on the union of a single chromosomally normal egg and sperm. Chromosomally normal eggs develop from precursor cells, called oocytes, that have undergone accurate chromosome segregation. The process of chromosome segregation is governed by the oocyte spindle, a unique cytoskeletal machine that splits chromatin content of the meiotically dividing oocyte. The oocyte spindle develops and functions in an idiosyncratic process, which is vulnerable to genetic variation in spindle-associated proteins. Human genetic variants in several spindle-associated proteins are associated with poor clinical fertility outcomes, suggesting that heritable etiologies for oocyte dysfunction leading to infertility exist and that the spindle is a crux for female fertility. This chapter examines the mammalian oocyte spindle through the lens of human genetic variation, covering the genes TUBB8, TACC3, CEP120, AURKA, AURKC, AURKB, BUB1B, and CDC20. Specifically, it explores how patient-identified variants perturb spindle development and function, and it links these molecular changes in the oocyte to their cognate clinical consequences, such as oocyte maturation arrest, elevated egg aneuploidy, primary ovarian insufficiency, and recurrent pregnancy loss. This discussion demonstrates that small genetic errors in oocyte meiosis can result in remarkably far-ranging embryonic consequences, and thus reveals the importance of the oocyte's fine machinery in sustaining life.
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Affiliation(s)
- Leelabati Biswas
- Department of Genetics, Rutgers University, Piscataway, NJ, USA
- Human Genetics Institute of New Jersey, Piscataway, NJ, USA
- Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, USA
| | - Karen Schindler
- Department of Genetics, Rutgers University, Piscataway, NJ, USA.
- Human Genetics Institute of New Jersey, Piscataway, NJ, USA.
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4
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Godoy PM, Oyedeji A, Mudd JL, Morikis VA, Zarov AP, Longmore GD, Fields RC, Kaufman CK. Functional analysis of recurrent CDC20 promoter variants in human melanoma. Commun Biol 2023; 6:1216. [PMID: 38030698 PMCID: PMC10686982 DOI: 10.1038/s42003-023-05526-2] [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: 09/05/2023] [Accepted: 10/30/2023] [Indexed: 12/01/2023] Open
Abstract
Small nucleotide variants in non-coding regions of the genome can alter transcriptional regulation, leading to changes in gene expression which can activate oncogenic gene regulatory networks. Melanoma is heavily burdened by non-coding variants, representing over 99% of total genetic variation, including the well-characterized TERT promoter mutation. However, the compendium of regulatory non-coding variants is likely still functionally under-characterized. We developed a pipeline to identify hotspots, i.e. recurrently mutated regions, in melanoma containing putatively functional non-coding somatic variants that are located within predicted melanoma-specific regulatory regions. We identified hundreds of statistically significant hotspots, including the hotspot containing the TERT promoter variants, and focused on a hotspot in the promoter of CDC20. We found that variants in the promoter of CDC20, which putatively disrupt an ETS motif, lead to lower transcriptional activity in reporter assays. Using CRISPR/Cas9, we generated an indel in the CDC20 promoter in human A375 melanoma cell lines and observed decreased expression of CDC20, changes in migration capabilities, increased growth of xenografts, and an altered transcriptional state previously associated with a more proliferative and less migratory state. Overall, our analysis prioritized several recurrent functional non-coding variants that, through downregulation of CDC20, led to perturbation of key melanoma phenotypes.
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Affiliation(s)
- Paula M Godoy
- Division of Medical Oncology, Department of Medicine and Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Abimbola Oyedeji
- Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Siteman Cancer Center, Washington University in Saint Louis, St. Louis, MO, USA
| | - Jacqueline L Mudd
- Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Siteman Cancer Center, Washington University in Saint Louis, St. Louis, MO, USA
| | - Vasilios A Morikis
- Departments of Medicine (Oncology) and Cell Biology and Physiology and the ICCE Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Anna P Zarov
- Division of Medical Oncology, Department of Medicine and Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Gregory D Longmore
- Siteman Cancer Center, Washington University in Saint Louis, St. Louis, MO, USA
- Departments of Medicine (Oncology) and Cell Biology and Physiology and the ICCE Institute, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Ryan C Fields
- Department of Surgery, Washington University School of Medicine, St. Louis, MO, USA
- Siteman Cancer Center, Washington University in Saint Louis, St. Louis, MO, USA
| | - Charles K Kaufman
- Division of Medical Oncology, Department of Medicine and Department of Developmental Biology, Washington University School of Medicine, St. Louis, MO, USA.
- Siteman Cancer Center, Washington University in Saint Louis, St. Louis, MO, USA.
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Xu M, Wu W, Zhao M, Chung JPW, Li TC, Chan DYL. Common dysmorphic oocytes and embryos in assisted reproductive technology laboratory in association with gene alternations. Int J Biochem Cell Biol 2022; 152:106298. [PMID: 36122887 DOI: 10.1016/j.biocel.2022.106298] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 09/13/2022] [Accepted: 09/14/2022] [Indexed: 11/29/2022]
Abstract
Amorphic or defected oocytes and embryos are commonly observed in assisted reproductive technology (ART) laboratories. It is believed that a proper gene expression at each stage of embryo development contributes to the possibility of a decent-quality embryo leading to successful implantation. Many studies reported that several defects in embryo morphology are associated with gene expressions during in vitro fertilization (IVF) treatment. There is lacking literature review on summarizing common morphological defects about gene alternations. In this review, we summarized the current literature. We selected 64 genes that have been reported to be involved in embryo morphological abnormalities in animals and humans, 30 of which were identified in humans and might be the causes of embryonic changes. Five papers focusing on associations of multiple gene expressions and embryo abnormalities using RNA transcriptomes were also included during the search. We have also reviewed our time-lapse image database with over 3000 oocytes/embryos to show morphological defects possibly related to gene alternations reported previously in the literature. This holistic review can better understand the associations between gene alternations and morphological changes. It is also beneficial to select important biomarkers with strong evidence in IVF practice and reveal their potential application in embryo selection. Also, identifying genes may help patients with genetic disorders avoid unnecessary treatments by providing preimplantation genetic testing for monogenic/single gene defects (PGT-M), reduce embryo replacements by less potential, and help scientists develop new methods for oocyte/embryo research in the near future.
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Affiliation(s)
- Murong Xu
- Assisted Reproductive Technology Unit, Department of Obstetrics and Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China; School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Waner Wu
- Assisted Reproductive Technology Unit, Department of Obstetrics and Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Mingpeng Zhao
- Assisted Reproductive Technology Unit, Department of Obstetrics and Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China; Department of Reproductive Medicine, Department of Obstetrics and Gynaecology, Guangdong Provincial People's Hospital, Guangdong Academy of Medical Sciences, Guangzhou, China
| | - Jacqueline Pui Wah Chung
- Assisted Reproductive Technology Unit, Department of Obstetrics and Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - Tin Chiu Li
- Assisted Reproductive Technology Unit, Department of Obstetrics and Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China
| | - David Yiu Leung Chan
- Assisted Reproductive Technology Unit, Department of Obstetrics and Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong, China.
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Chen OJ, Castellsagué E, Moustafa-Kamal M, Nadaf J, Rivera B, Fahiminiya S, Wang Y, Gamache I, Pacifico C, Jiang L, Carrot-Zhang J, Witkowski L, Berghuis AM, Schönberger S, Schneider D, Hillmer M, Bens S, Siebert R, Stewart CJR, Zhang Z, Chao WCH, Greenwood CMT, Barford D, Tischkowitz M, Majewski J, Foulkes WD, Teodoro JG. Germline Missense Variants in CDC20 Result in Aberrant Mitotic Progression and Familial Cancer. Cancer Res 2022; 82:3499-3515. [PMID: 35913887 DOI: 10.1158/0008-5472.can-21-3956] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 04/12/2022] [Accepted: 07/26/2022] [Indexed: 11/16/2022]
Abstract
CDC20 is a coactivator of the anaphase promoting complex/cyclosome (APC/C) and is essential for mitotic progression. APC/CCDC20 is inhibited by the spindle assembly checkpoint (SAC), which prevents premature separation of sister chromatids and aneuploidy in daughter cells. Although overexpression of CDC20 is common in many cancers, oncogenic mutations have never been identified in humans. Using whole-exome sequencing, we identified heterozygous missense CDC20 variants (L151R and N331K) that segregate with ovarian germ cell tumors in two families. Functional characterization showed these mutants retain APC/C activation activity but have impaired binding to BUBR1, a component of the SAC. Expression of L151R and N331K variants promoted mitotic slippage in HeLa cells and primary skin fibroblasts derived from carriers. Generation of mice carrying the N331K variant using CRISPR-Cas9 showed that, although homozygous N331K mice were nonviable, heterozygotes displayed accelerated oncogenicity of Myc-driven cancers. These findings highlight an unappreciated role for CDC20 variants as tumor-promoting genes. SIGNIFICANCE Two germline CDC20 missense variants that segregate with cancer in two families compromise the spindle assembly checkpoint and lead to aberrant mitotic progression, which could predispose cells to transformation. See related commentary by Villarroya-Beltri and Malumbres, p. 3432.
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Affiliation(s)
- Owen J Chen
- Goodman Cancer Institute, McGill University, Montréal, Québec, Canada
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
| | - Ester Castellsagué
- Department of Human Genetics, McGill University, Montréal, Québec, Canada
- Division of Medical Genetics and Cancer Axis, Lady Davis Institute, Segal Cancer Centre, Jewish General Hospital, Montréal, Québec, Canada
- Translational Research Laboratory, Catalan Institute of Oncology, Bellvitge Institute for Biomedical Research, L'Hospitalet de Llobregat, Barcelona, Spain
| | - Mohamed Moustafa-Kamal
- Goodman Cancer Institute, McGill University, Montréal, Québec, Canada
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
| | - Javad Nadaf
- McGill University and Génome Québec Innovation Centre, Montréal, Québec, Canada
| | - Barbara Rivera
- Cancer Axis, Lady Davis Institute, Jewish General Hospital, Montréal, Québec, Canada
- Hereditary Cancer Programme, Catalan Institute of Oncology, Bellvitge Institute for Biomedical Research, L'Hospitalet de Llobregat, Barcelona, Spain
- Gerald Bronfman Department of Oncology, McGill University, Montréal, Québec, Canada
| | - Somayyeh Fahiminiya
- Department of Human Genetics, McGill University, Montréal, Québec, Canada
- Cancer Research Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Yilin Wang
- Goodman Cancer Institute, McGill University, Montréal, Québec, Canada
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
| | - Isabelle Gamache
- Goodman Cancer Institute, McGill University, Montréal, Québec, Canada
| | - Caterina Pacifico
- Goodman Cancer Institute, McGill University, Montréal, Québec, Canada
- Department of Biology, McGill University, Montréal, Québec, Canada
| | - Lai Jiang
- Cancer Axis, Lady Davis Institute, Jewish General Hospital, Montréal, Québec, Canada
- Department of Epidemiology, Biostatistics & Occupational Health, McGill University, Montréal, Québec, Canada
| | - Jian Carrot-Zhang
- Department of Human Genetics, McGill University, Montréal, Québec, Canada
- Cancer Research Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Leora Witkowski
- Department of Human Genetics, McGill University, Montréal, Québec, Canada
- Division of Medical Genetics and Cancer Axis, Lady Davis Institute, Segal Cancer Centre, Jewish General Hospital, Montréal, Québec, Canada
| | - Albert M Berghuis
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
- Centre de Recherche en Biologie Structurale, McGill University, Montréal, Québec, Canada
- Department of Microbiology and Immunology, Montréal, Québec, Canada
| | - Stefan Schönberger
- Department of Pediatric Hematology and Oncology, Pediatrics III, University Hospital of Essen, University of Duisburg-Essen, Essen, Germany
| | - Dominik Schneider
- Clinic of Pediatrics, Dortmund Municipal Hospital, Dortmund, Germany
| | - Morten Hillmer
- Institute of Human Genetics, University of Ulm & Ulm University Medical Center, Ulm, Germany
| | - Susanne Bens
- Institute of Human Genetics, University of Ulm & Ulm University Medical Center, Ulm, Germany
| | - Reiner Siebert
- Institute of Human Genetics, University of Ulm & Ulm University Medical Center, Ulm, Germany
| | - Colin J R Stewart
- Department of Histopathology, King Edward Memorial Hospital, and School for Women's and Infants' Health, University of Western Australia, Perth, Australia
| | - Ziguo Zhang
- Institute of Cancer Research, London, United Kingdom
| | - William C H Chao
- Faculty of Health Sciences, University of Macau, Macau SAR, China
| | - Celia M T Greenwood
- Cancer Axis, Lady Davis Institute, Jewish General Hospital, Montréal, Québec, Canada
- Department of Epidemiology, Biostatistics & Occupational Health, McGill University, Montréal, Québec, Canada
- Departments of Oncology and Human Genetics, McGill University, Montréal, Québec, Canada
| | - David Barford
- Institute of Cancer Research, London, United Kingdom
| | - Marc Tischkowitz
- Department of Medical Genetics, National Institute for Health Research Cambridge Biomedical Research Centre, University of Cambridge, Cambridge, United Kingdom
| | - Jacek Majewski
- Department of Human Genetics, McGill University, Montréal, Québec, Canada
- Cancer Research Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - William D Foulkes
- Department of Human Genetics, McGill University, Montréal, Québec, Canada
- Division of Medical Genetics and Cancer Axis, Lady Davis Institute, Segal Cancer Centre, Jewish General Hospital, Montréal, Québec, Canada
- Program in Cancer Genetics, Department of Oncology and Human Genetics, McGill University, Montréal, Québec, Canada
- Division of Medical Genetics and Cancer Research Program, Research Institute of the McGill University Health Centre, Montréal, Québec, Canada
| | - Jose G Teodoro
- Goodman Cancer Institute, McGill University, Montréal, Québec, Canada
- Department of Biochemistry, McGill University, Montréal, Québec, Canada
- Department of Microbiology and Immunology, Montréal, Québec, Canada
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Bruno S, Ghelli Luserna di Rorà A, Napolitano R, Soverini S, Martinelli G, Simonetti G. CDC20 in and out of mitosis: a prognostic factor and therapeutic target in hematological malignancies. JOURNAL OF EXPERIMENTAL & CLINICAL CANCER RESEARCH : CR 2022; 41:159. [PMID: 35490245 PMCID: PMC9055704 DOI: 10.1186/s13046-022-02363-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 04/11/2022] [Indexed: 12/31/2022]
Abstract
Cell division cycle 20 homologue (CDC20) is a well-known regulator of cell cycle, as it controls the correct segregation of chromosomes during mitosis. Many studies have focused on the biological role of CDC20 in cancer development, as alterations of its functionality have been linked to genomic instability and evidence demonstrated that high CDC20 expression levels are associated with poor overall survival in solid cancers. More recently, novel CDC20 functions have been demonstrated or suggested, including the regulation of apoptosis and stemness properties and a correlation with immune cell infiltration. Here, we here summarize and discuss the role of CDC20 inside and outside mitosis, starting from its network of interacting proteins. In the last years, CDC20 has also attracted more interest in the blood cancer field, being overexpressed and showing an association with prognosis both in myeloid and lymphoid malignancies. Preclinical findings showed that selective CDC20 and APC/CCDC20/APC/CCDH1 inhibitors, namely Apcin and proTAME, are effective against lymphoma and multiple myeloma cells, resulting in mitotic arrest and apoptosis and synergizing with clinically-relevant drugs. The evidence and hypothesis presented in this review provide the input for further biological and chemical studies aiming to dissect novel potential CDC20 roles and targeting strategies in hematological malignancies.
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Affiliation(s)
- Samantha Bruno
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna and Institute of Hematology "L. e A. Seràgnoli", Bologna, Italy
| | - Andrea Ghelli Luserna di Rorà
- Biosciences Laboratory, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) "Dino Amadori", via Piero Maroncelli 40, 47014, Meldola, FC, Italy.
| | - Roberta Napolitano
- Biosciences Laboratory, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) "Dino Amadori", via Piero Maroncelli 40, 47014, Meldola, FC, Italy
| | - Simona Soverini
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna and Institute of Hematology "L. e A. Seràgnoli", Bologna, Italy
| | - Giovanni Martinelli
- Scientific Directorate, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) "Dino Amadori", via Piero Maroncelli 40, 47014, Meldola, FC, Italy
| | - Giorgia Simonetti
- Biosciences Laboratory, IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) "Dino Amadori", via Piero Maroncelli 40, 47014, Meldola, FC, Italy
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Cosper PF, Copeland SE, Tucker JB, Weaver BA. Chromosome Missegregation as a Modulator of Radiation Sensitivity. Semin Radiat Oncol 2022; 32:54-63. [PMID: 34861996 PMCID: PMC8883596 DOI: 10.1016/j.semradonc.2021.09.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Chromosome missegregation over the course of multiple cell divisions, termed chromosomal instability (CIN), is a hallmark of cancer. Multiple causes of CIN have been identified, including defects in the mitotic checkpoint, altered kinetochore-microtubule dynamics, centrosome amplification, and ionizing radiation. Here we review the types, mechanisms, and cellular implications of CIN. We discuss the evidence that CIN can promote tumors, suppress them, or do neither, depending on the rates of chromosome missegregration and the cellular context. Very high rates of chromosome missegregation lead to cell death due to loss of essential chromosomes; thus elevating CIN above a tolerable threshold provides a mechanistic opportunity to promote cancer cell death. Lethal rates of CIN can be achieved by a single insult or through a combination of insults. Because ionizing radiation induces CIN, additional therapies that increase CIN may serve as useful modulators of radiation sensitivity. Ultimately, quantifying the intrinsic CIN in a tumor and modulating this level pharmacologically as well as with radiation may allow for a more rational, personalized radiation therapy prescription, thereby decreasing side effects and increasing local control.
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Affiliation(s)
- Pippa F. Cosper
- Department of Human Oncology, University of Wisconsin-Madison, Madison, WI 53705, USA,University of Wisconsin Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Sarah E. Copeland
- Molecular & Cellular Pharmacology Graduate Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - John B. Tucker
- Cancer Biology Graduate Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Beth A. Weaver
- University of Wisconsin Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI 53705, USA,Department of Cellular and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705, USA,Department of Oncology/McArdle Laboratory for Cancer Research, University of Wisconsin-Madison, Madison, WI 53705, USA,Corresponding author: Beth A. Weaver, University of Wisconsin-Madison, 1111 Highland Ave, 6109 WIMR Tower 1, Madison, WI 53705-2275, Phone: 608-263-5309, Fax: 608-265-6905,
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9
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Trakala M, Aggarwal M, Sniffen C, Zasadil L, Carroll A, Ma D, Su XA, Wangsa D, Meyer A, Sieben CJ, Zhong J, Hsu PH, Paradis G, Ried T, Holland A, Van Deursen J, Amon A. Clonal selection of stable aneuploidies in progenitor cells drives high-prevalence tumorigenesis. Genes Dev 2021; 35:1079-1092. [PMID: 34266888 PMCID: PMC8336892 DOI: 10.1101/gad.348341.121] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Accepted: 06/04/2021] [Indexed: 12/16/2022]
Abstract
In this study Trakala et al. investigated how chromosome gains and losses, which are a frequent feature of human cancers, can overcome the detrimental effects of aneuploidy. They developed a novel mouse model that enables unprecedented levels of chromosome missegregation in the adult animal and their results show that the initial detrimental effects of random missegregation are outweighed by clonal selection, which is dependent on chromosomal location and the nature of specific genes and is sufficient to drive cancer. Chromosome gains and losses are a frequent feature of human cancers. However, how these aberrations can outweigh the detrimental effects of aneuploidy remains unclear. An initial comparison of existing chromosomal instability (CIN) mouse models suggests that aneuploidy accumulates to low levels in these animals. We therefore developed a novel mouse model that enables unprecedented levels of chromosome missegregation in the adult animal. At the earliest stages of T-cell development, cells with random chromosome gains and/or losses are selected against, but CIN eventually results in the expansion of progenitors with clonal chromosomal imbalances. Clonal selection leads to the development of T-cell lymphomas with stereotypic karyotypes in which chromosome 15, containing the Myc oncogene, is gained with high prevalence. Expressing human MYC from chromosome 6 (MYCChr6) is sufficient to change the karyotype of these lymphomas to include universal chromosome 6 gains. Interestingly, while chromosome 15 is still gained in MYCChr6 tumors after genetic ablation of the endogenous Myc locus, this chromosome is not efficiently gained after deletion of one copy of Rad21, suggesting a synergistic effect of both MYC and RAD21 in driving chromosome 15 gains. Our results show that the initial detrimental effects of random missegregation are outbalanced by clonal selection, which is dictated by the chromosomal location and nature of certain genes and is sufficient to drive cancer with high prevalence.
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Affiliation(s)
- Marianna Trakala
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Muskaan Aggarwal
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Courtney Sniffen
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Lauren Zasadil
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Allison Carroll
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Duanduan Ma
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Xiaofeng A Su
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Darawalee Wangsa
- Genetics Branch National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Ashleigh Meyer
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Cynthia J Sieben
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Jian Zhong
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Pei-Hsin Hsu
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Glenn Paradis
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
| | - Thomas Ried
- Genetics Branch National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Andrew Holland
- Department of Molecular Biology and Genetics, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Jan Van Deursen
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
| | - Angelika Amon
- David H. Koch Institute for Integrative Cancer Research, Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02142, USA
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10
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Novel Mutations in CDC20 Are Associated with Female Infertility Due to Oocyte Maturation Abnormality and Early Embryonic Arrest. Reprod Sci 2021; 28:1930-1938. [PMID: 33683667 DOI: 10.1007/s43032-021-00524-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2021] [Accepted: 03/01/2021] [Indexed: 10/22/2022]
Abstract
The cell division cycle 20 (CDC20) protein is a co-activator of anaphase-promoting complex/cyclosome (APC/C), required for mitotic exit and also meiotic exit, containing seven WD40 repeats in the C-terminus responsible for protein-protein interactions. Recently, a previous study has shown that biallelic mutations in CDC20 are causative for female infertility with abnormalities in oocyte maturation and embryonic development. This study is to further identify new mutations of CDC20 and the prevalence of variants in our cohort. A cohort of 50 primary infertile females with oocyte maturation abnormality and early embryonic arrest were recruited. Genomic DNA was isolated from peripheral blood samples. Mutation screening of all the coding regions of CDC20 was performed by Sanger sequencing. The pathogenicity of the identified variants on the CDC20 protein was accessed in silico. Two CDC20 variants, a nonsense mutation p.R262* and a missense mutation p.A211T, identified in one female of 50 unrelated affected individuals, accounting for a relative small proportion of this cohort (2%). In silico analysis revealed that the p.R262* would cause no production of protein or a truncated protein lacking five WD40 repeats in the C-terminus; and that p.A211T may interfere with the formation of a deep hydrophobic pocket and thus disturb the binding of CDC20 protein to the substrates of APC/C. This study identified two novel mutations in CDC20, further expanding the mutation spectrum of this gene. Our findings further confirm that biallelic mutations in CDC20 occur in a proportion of infertile females with oocyte maturation abnormality and early embryonic arrest.
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11
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Zhao L, Xue S, Yao Z, Shi J, Chen B, Wu L, Sun L, Xu Y, Yan Z, Li B, Mao X, Fu J, Zhang Z, Mu J, Wang W, Du J, Liu S, Dong J, Wang W, Li Q, He L, Jin L, Liang X, Kuang Y, Sun X, Wang L, Sang Q. Biallelic mutations in CDC20 cause female infertility characterized by abnormalities in oocyte maturation and early embryonic development. Protein Cell 2021; 11:921-927. [PMID: 32666501 PMCID: PMC7719138 DOI: 10.1007/s13238-020-00756-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Affiliation(s)
- Lin Zhao
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Songguo Xue
- Center of Assisted Reproduction, Shanghai East hospital, Tongji University, Shanghai, 200120, China
| | - Zhongyuan Yao
- The Reproductive Medical Center of Xiangya Hospital, Central South University, Changsha, 41008, China
| | - Juanzi Shi
- Reproductive Medicine Center, Shaanxi Maternal and Child Care Service Center, Xi'an, 710069, China
| | - Biaobang Chen
- NHC Key Lab of Reproduction Regulation (Shanghai Institute of Planned Parenthood Research), Fudan University, Shanghai, 200032, China
| | - Ling Wu
- Reproductive Medicine Center, Shanghai Ninth Hospital, Shanghai Jiao Tong University, Shanghai, 200011, China
| | - Lihua Sun
- Center of Assisted Reproduction, Shanghai East hospital, Tongji University, Shanghai, 200120, China
| | - Yao Xu
- Center of Assisted Reproduction, Shanghai East hospital, Tongji University, Shanghai, 200120, China
| | - Zheng Yan
- Reproductive Medicine Center, Shanghai Ninth Hospital, Shanghai Jiao Tong University, Shanghai, 200011, China
| | - Bin Li
- Reproductive Medicine Center, Shanghai Ninth Hospital, Shanghai Jiao Tong University, Shanghai, 200011, China
| | - Xiaoyan Mao
- Reproductive Medicine Center, Shanghai Ninth Hospital, Shanghai Jiao Tong University, Shanghai, 200011, China
| | - Jing Fu
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, 200011, China
| | - Zhihua Zhang
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Jian Mu
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Wenjing Wang
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Jing Du
- NHC Key Lab of Reproduction Regulation (Shanghai Institute of Planned Parenthood Research), Fudan University, Shanghai, 200032, China
| | - Shuai Liu
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Jie Dong
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Weijie Wang
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Qiaoli Li
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China
| | - Lin He
- Bio-X Center, Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders, Ministry of Education, Shanghai Jiao Tong University, Shanghai, 200030, China
| | - Li Jin
- State Key Laboratory of Genetic Engineering and Collaborative Innovation Center for Genetics and Development, School of Life Sciences, Fudan University, Shanghai, 200438, China
| | - Xiaozhen Liang
- Key Laboratory of Molecular Virology & Immunology, Institute Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, 200031, China
| | - Yanping Kuang
- Reproductive Medicine Center, Shanghai Ninth Hospital, Shanghai Jiao Tong University, Shanghai, 200011, China
| | - Xiaoxi Sun
- Shanghai Ji Ai Genetics and IVF Institute, Obstetrics and Gynecology Hospital, Fudan University, Shanghai, 200011, China
| | - Lei Wang
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China. .,Zhuhai Fudan Innovation Institute, Zhuhai, 519000, China. .,Shanghai Center for Women and Children's Health, Shanghai, 200062, China.
| | - Qing Sang
- Institute of Pediatrics, Children's Hospital of Fudan University and the Shanghai Key Laboratory of Medical Epigenetics, the International Co-laboratory of Medical Epigenetics and metabolism, Ministry of Science and technology and Institutes of Biomedical Sciences, State Key Laboratory of Genetic Engineering, Fudan University, Shanghai, 200032, China. .,Zhuhai Fudan Innovation Institute, Zhuhai, 519000, China.
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12
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APC/C ubiquitin ligase: Functions and mechanisms in tumorigenesis. Semin Cancer Biol 2020; 67:80-91. [PMID: 32165320 DOI: 10.1016/j.semcancer.2020.03.001] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 02/24/2020] [Accepted: 03/02/2020] [Indexed: 12/18/2022]
Abstract
The anaphase promoting complex/ cyclosome (APC/C), is an evolutionarily conserved protein complex essential for cellular division due to its role in regulating the mitotic transition from metaphase to anaphase. In this review, we highlight recent work that has shed light on our understanding of the role of APC/C coactivators, Cdh1 and Cdc20, in cancer initiation and development. We summarize the current state of knowledge regarding APC/C structure and function, as well as the distinct ways Cdh1 and Cdc20 are dysregulated in human cancer. We also discuss APC/C inhibitors, novel approaches for targeting the APC/C as a cancer therapy, and areas for future work.
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13
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Choi E, Yu H. Spindle Checkpoint Regulators in Insulin Signaling. Front Cell Dev Biol 2018; 6:161. [PMID: 30555826 PMCID: PMC6281718 DOI: 10.3389/fcell.2018.00161] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 11/08/2018] [Indexed: 12/17/2022] Open
Abstract
The spindle checkpoint ensures accurate chromosome segregation during mitosis and guards against aneuploidy. Insulin signaling governs metabolic homeostasis and cell growth, and its dysregulation leads to metabolic disorders, such as diabetes. These critical pathways have been extensively investigated, but a link between the two has not been established until recently. Our recent study reveals a critical role of spindle checkpoint regulators in insulin signaling and metabolic homeostasis through regulating endocytosis of the insulin receptor (IR). These findings have linked spindle checkpoint proteins to metabolic regulation, expanding the connection between cell division and metabolism. Here, we briefly review the unexpected roles of spindle checkpoint regulators in vesicle trafficking and insulin signaling.
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Affiliation(s)
- Eunhee Choi
- Department of Pharmacology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Hongtao Yu
- Department of Pharmacology, Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, United States
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14
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Simonetti G, Bruno S, Padella A, Tenti E, Martinelli G. Aneuploidy: Cancer strength or vulnerability? Int J Cancer 2018; 144:8-25. [PMID: 29981145 PMCID: PMC6587540 DOI: 10.1002/ijc.31718] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 06/05/2018] [Accepted: 06/14/2018] [Indexed: 12/12/2022]
Abstract
Aneuploidy is a very rare and tissue‐specific event in normal conditions, occurring in a low number of brain and liver cells. Its frequency increases in age‐related disorders and is one of the hallmarks of cancer. Aneuploidy has been associated with defects in the spindle assembly checkpoint (SAC). However, the relationship between chromosome number alterations, SAC genes and tumor susceptibility remains unclear. Here, we provide a comprehensive review of SAC gene alterations at genomic and transcriptional level across human cancers and discuss the oncogenic and tumor suppressor functions of aneuploidy. SAC genes are rarely mutated but frequently overexpressed, with a negative prognostic impact on different tumor types. Both increased and decreased SAC gene expression show oncogenic potential in mice. SAC gene upregulation may drive aneuploidization and tumorigenesis through mitotic delay, coupled with additional oncogenic functions outside mitosis. The genomic background and environmental conditions influence the fate of aneuploid cells. Aneuploidy reduces cellular fitness. It induces growth and contact inhibition, mitotic and proteotoxic stress, cell senescence and production of reactive oxygen species. However, aneuploidy confers an evolutionary flexibility by favoring genome and chromosome instability (CIN), cellular adaptation, stem cell‐like properties and immune escape. These properties represent the driving force of aneuploid cancers, especially under conditions of stress and pharmacological pressure, and are currently under investigation as potential therapeutic targets. Indeed, promising results have been obtained from synthetic lethal combinations exploiting CIN, mitotic defects, and aneuploidy‐tolerating mechanisms as cancer vulnerability.
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Affiliation(s)
- Giorgia Simonetti
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna and Institute of Hematology "L. e A. Seràgnoli", Bologna, Italy
| | - Samantha Bruno
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna and Institute of Hematology "L. e A. Seràgnoli", Bologna, Italy
| | - Antonella Padella
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna and Institute of Hematology "L. e A. Seràgnoli", Bologna, Italy
| | - Elena Tenti
- Department of Experimental, Diagnostic and Specialty Medicine, University of Bologna and Institute of Hematology "L. e A. Seràgnoli", Bologna, Italy
| | - Giovanni Martinelli
- Scientific Directorate, Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Meldola, Italy
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15
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Aziz K, Sieben CJ, Jeganathan KB, Hamada M, Davies BA, Velasco ROF, Rahman N, Katzmann DJ, van Deursen JM. Mosaic-variegated aneuploidy syndrome mutation or haploinsufficiency in Cep57 impairs tumor suppression. J Clin Invest 2018; 128:3517-3534. [PMID: 30035751 PMCID: PMC6063474 DOI: 10.1172/jci120316] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2018] [Accepted: 06/06/2018] [Indexed: 12/29/2022] Open
Abstract
A homozygous truncating frameshift mutation in CEP57 (CEP57T/T) has been identified in a subset of mosaic-variegated aneuploidy (MVA) patients; however, the physiological roles of the centrosome-associated protein CEP57 that contribute to disease are unknown. To investigate these, we have generated a mouse model mimicking this disease mutation. Cep57T/T mice died within 24 hours after birth with short, curly tails and severely impaired vertebral ossification. Osteoblasts in lumbosacral vertebrae of Cep57T/T mice were deficient for Fgf2, a Cep57 binding partner implicated in diverse biological processes, including bone formation. Furthermore, a broad spectrum of tissues of Cep57T/T mice had severe aneuploidy at birth, consistent with the MVA patient phenotype. Cep57T/T mouse embryonic fibroblasts and patient-derived skin fibroblasts failed to undergo centrosome maturation in G2 phase, causing premature centriole disjunction, centrosome amplification, aberrant spindle formation, and high rates of chromosome missegregation. Mice heterozygous for the truncating frameshift mutation or a Cep57-null allele were overtly indistinguishable from WT mice despite reduced Cep57 protein levels, yet prone to aneuploidization and cancer, with tumors lacking evidence for loss of heterozygosity. This study identifies Cep57 as a haploinsufficient tumor suppressor with biologically diverse roles in centrosome maturation and Fgf2-mediated bone formation.
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Affiliation(s)
- Khaled Aziz
- Department of Biochemistry and Molecular Biology and
| | | | - Karthik B. Jeganathan
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | - Masakazu Hamada
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, USA
| | | | | | - Nazneen Rahman
- Division of Genetics and Epidemiology, The Institute of Cancer Research, London, United Kingdom
| | | | - Jan M. van Deursen
- Department of Biochemistry and Molecular Biology and
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, USA
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16
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Borges DDP, Dos Santos AWA, Paier CRK, Ribeiro HL, Costa MB, Farias IR, de Oliveira RTG, França IGDF, Cavalcante GM, Magalhães SMM, Pinheiro RF. Prognostic importance of Aurora Kinases and mitotic spindle genes transcript levels in Myelodysplastic syndrome. Leuk Res 2017; 64:61-70. [PMID: 29220700 DOI: 10.1016/j.leukres.2017.11.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 11/22/2017] [Accepted: 11/27/2017] [Indexed: 12/25/2022]
Abstract
Myelodysplastic syndrome (MDS) are a heterogeneous group of clonal disease characterized by insufficiency of bone marrow, increase of apoptosis and increased risk of acute leukemia progression. Proteins related to the mitotic spindle (AURKA, AURKB, TPX2), to the mitotic checkpoint (MAD2, CDC20) and the regulation of the cell cycle (p21) are directly related to chromosomal stability and tumor development. This study aimed to evaluate the mRNA expression levels of these genes in 101 MDS patients using a real-time PCR methodology. We identified that CDC20 expression are increased in patients with dysmegakaryopoiesis (p=0.024), thrombocytopenia (p=0.000) and high-risk patients (p=0.014, 0.018) MAD2 expression are decreased in patients with 2 or 3 cytopenias (p=0.000) and neutrophil below 800/mm3. TPX2 is also overexpressed in patients presenting dysmegakaryopoiesis (p=0.009). A decrease in AURKA and AURKB expression were observed in patients with altered karyotype (p=0.000), who presented dysplasia in 3 lineages (p=0.000; 0.017) and hemoglobin inferior to 8g/dL (p=0.024). The expression of AURKA, AURKB and MAD2 (p=0.000; 0.001; 0.025) were decreased in patients with hypoplastic MDS, associated with high frequency of chromosomal alterations and high mortality rate. This study reaffirms the importance of aurora kinases and mitotic spindle genes to the pathogenesis and clinical evolution of MDS.
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Affiliation(s)
- Daniela de Paula Borges
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Post-Graduate Program in Medical Science, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Antônio Wesley Araújo Dos Santos
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | | | - Howard Lopes Ribeiro
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Post-Graduate Program in Medical Science, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Marília Braga Costa
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Post-Graduate Program in Medical Science, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Izabelle Rocha Farias
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Post-Graduate Program in Medical Science, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Roberta Taiane Germano de Oliveira
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Post-Graduate Program in Medical Science, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Ivo Gabriel da Frota França
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Gabrielle Melo Cavalcante
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Sílvia Maria Meira Magalhães
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Post-Graduate Program in Medical Science, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil
| | - Ronald Feitosa Pinheiro
- Cancer Cytogenomic Laboratory, Federal University of Ceara, Fortaleza, Ceara, Brazil; Post-Graduate Program in Medical Science, Federal University of Ceara, Fortaleza, Ceara, Brazil; Center for Research and Drug Development (NPDM), Federal University of Ceara, Fortaleza, Ceara, Brazil; Post-Graduate Program of Pathology, Federal University of Ceara, Fortaleza, Ceara, Brazil.
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17
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Funk LC, Zasadil LM, Weaver BA. Living in CIN: Mitotic Infidelity and Its Consequences for Tumor Promotion and Suppression. Dev Cell 2017; 39:638-652. [PMID: 27997823 DOI: 10.1016/j.devcel.2016.10.023] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Errors in chromosome segregation during mitosis have been recognized as a hallmark of tumor cells since the late 1800s, resulting in the long-standing hypothesis that mitotic abnormalities drive tumorigenesis. Recent work has shown that mitotic defects can promote tumors, suppress them, or do neither, depending on the rate of chromosome missegregation. Here we discuss the causes of chromosome missegregation, their effects on tumor initiation and progression, and the evidence that increasing the rate of chromosome missegregation may be an effective chemotherapeutic strategy.
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Affiliation(s)
- Laura C Funk
- Molecular and Cellular Pharmacology Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Lauren M Zasadil
- Molecular and Cellular Pharmacology Training Program, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Beth A Weaver
- Department of Cell and Regenerative Biology, Carbone Cancer Center, University of Wisconsin-Madison, 1111 Highland Avenue, 6109 WIMR I, Madison, WI 53705-2275, USA.
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18
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Borg NA, Dixit VM. Ubiquitin in Cell-Cycle Regulation and Dysregulation in Cancer. ANNUAL REVIEW OF CANCER BIOLOGY-SERIES 2017. [DOI: 10.1146/annurev-cancerbio-040716-075607] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Uncontrolled cell proliferation and genomic instability are common features of cancer and can arise from, respectively, the loss of cell-cycle control and defective checkpoints. Ubiquitin-mediated proteolysis, ultimately executed by ubiquitin-ligating enzymes (E3s), plays a key part in cell-cycle regulation and is dominated by two multisubunit E3s, the anaphase-promoting complex (or cyclosome) (APC/C) and SKP1–cullin-1–F-box (SCF) complex. We highlight the role of APC/C and the SCF bound to F-box proteins, FBXW7, SKP2, and β-TrCP, in regulating the abundance of select fundamental proteins, primarily during the cell cycle, that are associated with human cancer. The clinical success of the first proteasome inhibitor, bortezomib, in treating multiple myeloma and mantle-cell lymphoma set the precedent for viewing the ubiquitin–proteasome system as a druggable target for cancer. Given that there are more E3s than kinases, selective, small-molecule E3 inhibitors have the potential of opening up another dimension in the therapeutic armamentarium for the treatment of cancer.
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Affiliation(s)
- Natalie A. Borg
- Cancer Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
| | - Vishva M. Dixit
- Department of Physiological Chemistry, Genentech Inc., South San Francisco, California 94080
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19
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Abstract
For over a century, the abnormal movement or number of centrosomes has been linked with errors of chromosomes distribution in mitosis. While not essential for the formation of the mitotic spindle, the presence and location of centrosomes has a major influence on the manner in which microtubules interact with the kinetochores of replicated sister chromatids and the accuracy with which they migrate to resulting daughter cells. A complex network has evolved to ensure that cells contain the proper number of centrosomes and that their location is optimal for effective attachment of emanating spindle fibers with the kinetochores. The components of this network are regulated through a series of post-translational modifications, including ubiquitin and ubiquitin-like modifiers, which coordinate the timing and strength of signaling events key to the centrosome cycle. In this review, we examine the role of the ubiquitin system in the events relating to centriole duplication and centrosome separation, and discuss how the disruption of these functions impacts chromosome segregation.
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20
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Choi E, Zhang X, Xing C, Yu H. Mitotic Checkpoint Regulators Control Insulin Signaling and Metabolic Homeostasis. Cell 2016; 166:567-581. [PMID: 27374329 DOI: 10.1016/j.cell.2016.05.074] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 12/09/2015] [Accepted: 05/24/2016] [Indexed: 01/08/2023]
Abstract
Insulin signaling regulates many facets of animal physiology. Its dysregulation causes diabetes and other metabolic disorders. The spindle checkpoint proteins MAD2 and BUBR1 prevent precocious chromosome segregation and suppress aneuploidy. The MAD2 inhibitory protein p31(comet) promotes checkpoint inactivation and timely chromosome segregation. Here, we show that whole-body p31(comet) knockout mice die soon after birth and have reduced hepatic glycogen. Liver-specific ablation of p31(comet) causes insulin resistance, hyperinsulinemia, glucose intolerance, and hyperglycemia and diminishes the plasma membrane localization of the insulin receptor (IR) in hepatocytes. MAD2 directly binds to IR and facilitates BUBR1-dependent recruitment of the clathrin adaptor AP2 to IR. p31(comet) blocks the MAD2-BUBR1 interaction and prevents spontaneous clathrin-mediated IR endocytosis. BUBR1 deficiency enhances insulin sensitivity in mice. BUBR1 depletion in hepatocytes or the expression of MAD2-binding-deficient IR suppresses the metabolic phenotypes of p31(comet) ablation. Our findings establish a major IR regulatory mechanism and link guardians of chromosome stability to nutrient metabolism.
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Affiliation(s)
- Eunhee Choi
- Howard Hughes Medical Institute, Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Xiangli Zhang
- Bioinformatics Core, Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Chao Xing
- Bioinformatics Core, Eugene McDermott Center for Human Growth and Development, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA
| | - Hongtao Yu
- Howard Hughes Medical Institute, Department of Pharmacology, University of Texas Southwestern Medical Center, 6001 Forest Park Road, Dallas, TX 75390, USA.
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21
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Zasadil LM, Britigan EMC, Ryan SD, Kaur C, Guckenberger DJ, Beebe DJ, Moser AR, Weaver BA. High rates of chromosome missegregation suppress tumor progression but do not inhibit tumor initiation. Mol Biol Cell 2016; 27:1981-9. [PMID: 27146113 PMCID: PMC4927272 DOI: 10.1091/mbc.e15-10-0747] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 04/23/2016] [Indexed: 11/11/2022] Open
Abstract
Aneuploidy, an abnormal chromosome number that deviates from a multiple of the haploid, has been recognized as a common feature of cancers for >100 yr. Previously, we showed that the rate of chromosome missegregation/chromosomal instability (CIN) determines the effect of aneuploidy on tumors; whereas low rates of CIN are weakly tumor promoting, higher rates of CIN cause cell death and tumor suppression. However, whether high CIN inhibits tumor initiation or suppresses the growth and progression of already initiated tumors remained unclear. We tested this using the Apc(Min/+) mouse intestinal tumor model, in which effects on tumor initiation versus progression can be discriminated. Apc(Min/+) cells exhibit low CIN, and we generated high CIN by reducing expression of the kinesin-like mitotic motor protein CENP-E. CENP-E(+/-);Apc(Min/+) doubly heterozygous cells had higher rates of chromosome missegregation than singly heterozygous cells, resulting in increased cell death and a substantial reduction in tumor progression compared with Apc(Min/+) animals. Intestinal organoid studies confirmed that high CIN does not inhibit tumor cell initiation but does inhibit subsequent cell growth. These findings support the conclusion that increasing the rate of chromosome missegregation could serve as a successful chemotherapeutic strategy.
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Affiliation(s)
- Lauren M Zasadil
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705 Molecular and Cellular Pharmacology Training Program, University of Wisconsin-Madison, Madison, WI 53705
| | - Eric M C Britigan
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705 Molecular and Cellular Pharmacology Training Program, University of Wisconsin-Madison, Madison, WI 53705
| | - Sean D Ryan
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705
| | - Charanjeet Kaur
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705
| | - David J Guckenberger
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53705
| | - David J Beebe
- Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53705 Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI 53705
| | - Amy R Moser
- Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI 53705 Department of Human Oncology, University of Wisconsin-Madison, Madison, WI 53705
| | - Beth A Weaver
- Department of Cell and Regenerative Biology, University of Wisconsin-Madison, Madison, WI 53705 Carbone Cancer Center, University of Wisconsin-Madison, Madison, WI 53705
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22
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Greil C, Follo M, Engelhardt M, Wäsch R. The Use of SNAP Labeling to Study Cell Cycle Oscillatory Proteins. Methods Mol Biol 2016; 1342:201-208. [PMID: 26254925 DOI: 10.1007/978-1-4939-2957-3_11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Tightly controlled degradation of specific regulatory proteins is crucial for transitioning to the next cell cycle phase, ensuring precise DNA replication and an equal distribution of chromosomes to provide genomic stability and avoid tumorigenesis. To study mitotic control at the metaphase-to-anaphase transition, a histone H2-GFP-based reporter system was established, allowing simultaneous monitoring of the alignment of mitotic chromosomes and cyclin B proteolysis. To depict the proteolytic profile, a chimeric cyclin B-SNAP reporter molecule that can be labeled with a fluorochrome-carrying SNAP substrate was generated for measurement of the decline in fluorescence intensity via live-cell imaging. This reporter system can be adapted for other cell cycle oscillatory proteins.
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Affiliation(s)
- Christine Greil
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center, Hugstetter Strasse 55, 79106, Freiburg, Germany
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23
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Das T, Roy KS, Chakrabarti T, Mukhopadhyay S, Roychoudhury S. Withaferin A modulates the Spindle assembly checkpoint by degradation of Mad2-Cdc20 complex in colorectal cancer cell lines. Biochem Pharmacol 2014; 91:31-9. [PMID: 24995417 DOI: 10.1016/j.bcp.2014.06.022] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2014] [Revised: 06/20/2014] [Accepted: 06/23/2014] [Indexed: 02/01/2023]
Abstract
Withania somnifera L. Dunal (Ashwagandha) is used over centuries in the ayurvedic medicines in India. Withaferin A, a withanolide, is the major compound present in leaf extract of the plant which shows anticancer activity against leukemia, breast cancer and colorectal cancer. It arrests the ovarian cancer cells in the G2/M phase in dose dependent manner. In the current study we show the effect of Withaferin A on cell cycle regulation of colorectal cancer cell lines HCT116 and SW480 and its effect on cell fate. Treatment of these cells with this compound leads to apoptosis in a dose dependent manner. It causes the G2/M arrest in both the cell lines. We show that Withaferin A (WA) causes mitotic delay by blocking Spindle assembly checkpoint (SAC) function. Apoptosis induced by Withaferin A is associated with proteasomal degradation of Mad2 and Cdc20, an important constituent of the Spindle Checkpoint Complex. Further overexpression of Mad2 partially rescues the deleterious effect of WA by restoring proper anaphase initiation and keeping more number of cells viable. We hypothesize that Withaferin A kills cancer cells by delaying the mitotic exit followed by inducing chromosome instability.
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Affiliation(s)
- Tania Das
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India.
| | - Kumar Singha Roy
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Tulika Chakrabarti
- Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Sibabrata Mukhopadhyay
- Medicinal Chemistry Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India
| | - Susanta Roychoudhury
- Cancer Biology and Inflammatory Disorder Division, CSIR-Indian Institute of Chemical Biology, 4, Raja S.C. Mullick Road, Jadavpur, Kolkata 700032, India.
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24
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Nam HJ, van Deursen JM. Cyclin B2 and p53 control proper timing of centrosome separation. Nat Cell Biol 2014; 16:538-49. [PMID: 24776885 PMCID: PMC4379487 DOI: 10.1038/ncb2952] [Citation(s) in RCA: 128] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2013] [Accepted: 03/17/2014] [Indexed: 12/14/2022]
Abstract
Cyclins B1 and B2 are frequently elevated in human cancers and are associated with tumour aggressiveness and poor clinical outcome; however, whether and how B-type cyclins drive tumorigenesis is unknown. Here we show that cyclin B1 and B2 transgenic mice are highly prone to tumours, including tumour types where B-type cyclins serve as prognosticators. Cyclins B1 and B2 both induce aneuploidy when overexpressed but through distinct mechanisms, with cyclin B1 inhibiting separase activation, leading to anaphase bridges, and cyclin B2 triggering aurora-A-mediated Plk1 hyperactivation, resulting in accelerated centrosome separation and lagging chromosomes. Complementary experiments revealed that cyclin B2 and p53 act antagonistically to control aurora-A-mediated centrosome splitting and accurate chromosome segregation in normal cells. These data demonstrate a causative link between B-type cyclin overexpression and tumour pathophysiology, and uncover previously unknown functions of cyclin B2 and p53 in centrosome separation that may be perturbed in many human cancers.
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Affiliation(s)
- Hyun-Ja Nam
- Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
| | - Jan M. van Deursen
- Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
- Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
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25
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Petsalaki E, Zachos G. Chk2 prevents mitotic exit when the majority of kinetochores are unattached. J Cell Biol 2014; 205:339-56. [PMID: 24798733 PMCID: PMC4018780 DOI: 10.1083/jcb.201310071] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Accepted: 04/04/2014] [Indexed: 11/29/2022] Open
Abstract
The spindle checkpoint delays exit from mitosis in cells with spindle defects. In this paper, we show that Chk2 is required to delay anaphase onset when microtubules are completely depolymerized but not in the presence of relatively few unattached kinetochores. Mitotic exit in Chk2-deficient cells correlates with reduced levels of Mps1 protein and increased Cdk1-tyrosine 15 inhibitory phosphorylation. Chk2 localizes to kinetochores and is also required for Aurora B-serine 331 phosphorylation in nocodazole or unperturbed early prometaphase. Serine 331 phosphorylation contributed to prometaphase accumulation in nocodazole after partial Mps1 inhibition and was required for spindle checkpoint establishment at the beginning of mitosis. In addition, expression of a phosphomimetic S331E mutant Aurora B rescued chromosome alignment or segregation in Chk2-deficient cells. We propose that Chk2 stabilizes Mps1 and phosphorylates Aurora B-serine 331 to prevent mitotic exit when most kinetochores are unattached. These results highlight mechanisms of an essential function of Chk2 in mitosis.
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Affiliation(s)
- Eleni Petsalaki
- Department of Biology, University of Crete, Heraklion 70013, Greece
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26
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Krenn V, Overlack K, Primorac I, van Gerwen S, Musacchio A. KI Motifs of Human Knl1 Enhance Assembly of Comprehensive Spindle Checkpoint Complexes around MELT Repeats. Curr Biol 2014; 24:29-39. [DOI: 10.1016/j.cub.2013.11.046] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2013] [Revised: 11/11/2013] [Accepted: 11/25/2013] [Indexed: 10/25/2022]
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27
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CDC20 downregulation impairs spindle morphology and causes reduced first polar body emission during bovine oocyte maturation. Theriogenology 2013; 81:535-44. [PMID: 24360405 DOI: 10.1016/j.theriogenology.2013.11.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 11/02/2013] [Accepted: 11/05/2013] [Indexed: 11/22/2022]
Abstract
The cell division cycle protein 20 (CDC20) is an essential regulator of cell division, encoded by the CDC20 gene. However, the role of CDC20 in bovine oocyte maturation is unknown. In this study, CDC20 morpholino antisense oligonucleotides (MOs) were microinjected into the cytoplasm of bovine oocytes to block the translation of CDC20 mRNA. CDC20 downregulation significantly reduced the rate of first polar body emission (PB1). Further analysis indicated that oocytes treated with CDC20 MO arrested before or at meiotic stage I with abnormal spindles. To further confirm the functions of CDC20 during oocyte meiotic division, CDC20 MOs were microinjected into oocytes together with a supplementary PB1. The results showed that newly synthesized CDC20 was not necessary at the meiosis II-to-anaphase II transition. Our data suggest that CDC20 is required for spindle assembly, chromosomal segregation, and PB1 extrusion during bovine oocyte maturation.
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28
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Chromosome missegregation rate predicts whether aneuploidy will promote or suppress tumors. Proc Natl Acad Sci U S A 2013; 110:E4134-41. [PMID: 24133140 DOI: 10.1073/pnas.1317042110] [Citation(s) in RCA: 187] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Aneuploidy, a chromosome content other than a multiple of the haploid number, is a common feature of cancer cells. Whole chromosomal aneuploidy accompanying ongoing chromosomal instability in mice resulting from reduced levels of the centromere-linked motor protein CENP-E has been reported to increase the incidence of spleen and lung tumors, but to suppress tumors in three other contexts. Exacerbating chromosome missegregation in CENP-E(+/-) mice by reducing levels of another mitotic checkpoint component, Mad2, is now shown to result in elevated cell death and decreased tumor formation compared with reduction of either protein alone. Furthermore, we determine that the additional contexts in which increased whole-chromosome missegregation resulting from reduced CENP-E suppresses tumor formation have a preexisting, elevated basal level of chromosome missegregation that is exacerbated by reduction of CENP-E. Tumors arising from primary causes that do not generate chromosomal instability, including loss of the INK4a tumor suppressor and microsatellite instability from reduction of the DNA mismatch repair protein MLH1, are unaffected by CENP-E-dependent chromosome missegregation. These findings support a model in which low rates of chromosome missegregation can promote tumorigenesis, whereas missegregation of high numbers of chromosomes leads to cell death and tumor suppression.
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29
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Kotani T, Yasuda K, Ota R, Yamashita M. Cyclin B1 mRNA translation is temporally controlled through formation and disassembly of RNA granules. J Cell Biol 2013; 202:1041-55. [PMID: 24062337 PMCID: PMC3787373 DOI: 10.1083/jcb.201302139] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 08/15/2013] [Indexed: 11/22/2022] Open
Abstract
Temporal control of messenger RNA (mRNA) translation is an important mechanism for regulating cellular, neuronal, and developmental processes. However, mechanisms that coordinate timing of translational activation remain largely unresolved. Full-grown oocytes arrest meiosis at prophase I and deposit dormant mRNAs. Of these, translational control of cyclin B1 mRNA in response to maturation-inducing hormone is important for normal progression of oocyte maturation, through which oocytes acquire fertility. In this study, we found that dormant cyclin B1 mRNA forms granules in the cytoplasm of zebrafish and mouse oocytes. Real-time imaging of translation revealed that the granules disassemble at the time of translational activation during maturation. Formation of cyclin B1 RNA granules requires binding of the mRNA to Pumilio1 protein and depends on actin filaments. Disruption of cyclin B1 RNA granules accelerated the timing of their translational activation after induction of maturation, whereas stabilization hindered translational activation. Thus, our results suggest that RNA granule formation is critical for the regulation of timing of translational activation.
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Affiliation(s)
- Tomoya Kotani
- Department of Biological Sciences, Faculty of Science, and Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Kyota Yasuda
- Department of Biological Sciences, Faculty of Science, and Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Ryoma Ota
- Department of Biological Sciences, Faculty of Science, and Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Masakane Yamashita
- Department of Biological Sciences, Faculty of Science, and Biosystems Science Course, Graduate School of Life Science, Hokkaido University, Sapporo 060-0810, Japan
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30
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Schnerch D, Follo M, Felthaus J, Engelhardt M, Wäsch R. The 3' untranslated region of the cyclin B mRNA is not sufficient to enhance the synthesis of cyclin B during a mitotic block in human cells. PLoS One 2013; 8:e74379. [PMID: 24058555 PMCID: PMC3772928 DOI: 10.1371/journal.pone.0074379] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 07/31/2013] [Indexed: 12/15/2022] Open
Abstract
Antimitotic agents are frequently used to treat solid tumors and hematologic malignancies. However, one major limitation of antimitotic approaches is mitotic slippage, which is driven by slow degradation of cyclin B during a mitotic block. The extent to which cyclin B levels decline is proposed to be governed by an equilibrium between cyclin B synthesis and degradation. It was recently shown that the 3' untranslated region (UTR) of the murine cyclin B mRNA contributes to the synthesis of cyclin B during mitosis in murine cells. Using a novel live-cell imaging-based technique allowing us to study synthesis and degradation of cyclin B simultaneously at the single cell level, we tested here the role of the human cyclin B 3'UTR in regulating cyclin B synthesis during mitosis in human cells. We observed that the cyclin B 3'UTR was not sufficient to enhance cyclin B synthesis in human U2Os, HeLa or hTERT RPE-1 cells. A better understanding of how the equilibrium of cyclin B is regulated in mitosis may contribute to the development of improved therapeutic approaches to prevent mitotic slippage in cancer cells treated with antimitotic agents.
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Affiliation(s)
- Dominik Schnerch
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center, Freiburg, Germany
| | - Marie Follo
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center, Freiburg, Germany
| | - Julia Felthaus
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center, Freiburg, Germany
| | - Monika Engelhardt
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center, Freiburg, Germany
| | - Ralph Wäsch
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center, Freiburg, Germany
- * E-mail:
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31
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Abstract
During mitosis and meiosis, the spindle assembly checkpoint acts to maintain genome stability by delaying cell division until accurate chromosome segregation can be guaranteed. Accuracy requires that chromosomes become correctly attached to the microtubule spindle apparatus via their kinetochores. When not correctly attached to the spindle, kinetochores activate the spindle assembly checkpoint network, which in turn blocks cell cycle progression. Once all kinetochores become stably attached to the spindle, the checkpoint is inactivated, which alleviates the cell cycle block and thus allows chromosome segregation and cell division to proceed. Here we review recent progress in our understanding of how the checkpoint signal is generated, how it blocks cell cycle progression and how it is extinguished.
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Affiliation(s)
- Pablo Lara-Gonzalez
- Faculty of Life Sciences, University of Manchester, Michael Smith Building, Oxford Road, Manchester M13 9PT, UK
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32
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Karri ND, Xie H, Wise JP. Chronic Exposure to Particulate Hexavalent Chromium Alters Cdc20 Protein Localization, Interactions and Expression. JOURNAL OF CARCINOGENESIS & MUTAGENESIS 2013; 4:1000140. [PMID: 33312751 PMCID: PMC7730059 DOI: 10.4172/2157-2518.1000140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Hexavalent chromium [Cr(VI)] compounds are well established human lung carcinogens, but it is unknown how they cause lung cancer in humans. Recent data indicate that Cr(VI) induces chromosome instability in human lung cells, and genomic instability is considered a leading mechanism to explain chromate carcinogenesis. The Spindle Assembly Checkpoint (SAC) is a critical regulator of the metaphase-to-anaphase transition and ensures genome stability by preventing chromosomal missegregation events. Bypass of the SAC can lead to genomic instability, manifested as aneuploidy, which eventually leads to tumor formation and cancer. Recent studies in our laboratory demonstrated that chronic exposure to zinc chromate induces SAC bypass in a concentration- and time-dependent manner in human lung fibroblasts. To further study these events, we focused on the cell division cycle 20 (Cdc20) protein, a downstream effector protein in the SAC. Cdc20 has not been studied after Cr(VI) exposure, but other studies show that experimentally induced alterations of Cdc20 localization to kinetochores or of Cdc20 protein expression leads to aneuploidy. Here, we investigated the effects of zinc chromate, a particulate Cr(VI) compound, on Cdc20 localization, protein expression and interactions. Our data show Cdc20 is a target for particulate Cr(VI). Chronic zinc chromate exposure altered Cdc20 kinetochore localization and reduced the interaction of phosphorylated Cdc20 with Mad2, which may underlie zinc chromate-induced SAC bypass.
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Affiliation(s)
- Naga D. Karri
- Wise Laboratory of Environmental and Genetic Toxicology, Maine Center for Toxicology and Environmental Health, Department of Applied Medical Science, University of Southern Maine, USA
| | - Hong Xie
- Wise Laboratory of Environmental and Genetic Toxicology, Maine Center for Toxicology and Environmental Health, Department of Applied Medical Science, University of Southern Maine, USA
| | - John Pierce Wise
- Wise Laboratory of Environmental and Genetic Toxicology, Maine Center for Toxicology and Environmental Health, Department of Applied Medical Science, University of Southern Maine, USA
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33
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Zasadil LM, Britigan EMC, Weaver BA. 2n or not 2n: Aneuploidy, polyploidy and chromosomal instability in primary and tumor cells. Semin Cell Dev Biol 2013; 24:370-9. [PMID: 23416057 DOI: 10.1016/j.semcdb.2013.02.001] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2012] [Revised: 01/28/2013] [Accepted: 02/06/2013] [Indexed: 12/12/2022]
Abstract
Mitotic defects leading to aneuploidy have been recognized as a hallmark of tumor cells for over 100 years. Current data indicate that ∼85% of human cancers have missegregated chromosomes to become aneuploid. Some maintain a stable aneuploid karyotype, while others consistently missegregate chromosomes over multiple divisions due to chromosomal instability (CIN). Both aneuploidy and CIN serve as markers of poor prognosis in diverse human cancers. Despite this, aneuploidy is generally incompatible with viability during development, and some aneuploid karyotypes cause a proliferative disadvantage in somatic cells. In vivo, the intentional introduction of aneuploidy can promote tumors, suppress them, or do neither. Here, we summarize current knowledge of the effects of aneuploidy and CIN on proliferation and cell death in nontransformed cells, as well as on tumor promotion, suppression, and prognosis.
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Affiliation(s)
- Lauren M Zasadil
- Department of Cell and Regenerative Biology, University of Wisconsin, Madison, WI 53705, USA
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34
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Nakayama Y, Yamaguchi N. Role of cyclin B1 levels in DNA damage and DNA damage-induced senescence. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2013; 305:303-37. [PMID: 23890385 DOI: 10.1016/b978-0-12-407695-2.00007-x] [Citation(s) in RCA: 71] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The cyclin B1-Cdk1 complex is a key regulator of mitotic entry. A large number of proteins are phosphorylated by the cyclin B1-Cdk1 complex prior to mitotic entry. Regulation of the mitotic events is linked to the control of the activity of the cyclin B1-Cdk1 complex to make cells enter mitosis, arrest at G2-phase, or skip mitosis. The roles of cyclin B1 levels in DNA damage are described. The ATM/ATR pathway acts as a molecular switch for regulating cell fates, flipping between cell death via progress into mitosis and polyploidization via sustained G2 arrest upon DNA damage, where cyclin B1 degradation is important for inducing polyploidization. The decrease in cyclin B1 levels that is induced by DNA damage leads to polyploidization in DNA damage-induced senescence. A useful method for monitoring the expression level of cyclin B1 throughout cell cycle progression in living cells is also presented.
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Affiliation(s)
- Yuji Nakayama
- Department of Biochemistry & Molecular Biology, Kyoto Pharmaceutical University, Kyoto, Japan.
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35
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Wijshake T, Malureanu LA, Baker DJ, Jeganathan KB, van de Sluis B, van Deursen JM. Reduced life- and healthspan in mice carrying a mono-allelic BubR1 MVA mutation. PLoS Genet 2012; 8:e1003138. [PMID: 23300461 PMCID: PMC3531486 DOI: 10.1371/journal.pgen.1003138] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Accepted: 10/18/2012] [Indexed: 01/10/2023] Open
Abstract
Mosaic Variegated Aneuploidy (MVA) syndrome is a rare autosomal recessive disorder characterized by inaccurate chromosome segregation and high rates of near-diploid aneuploidy. Children with MVA syndrome die at an early age, are cancer prone, and have progeroid features like facial dysmorphisms, short stature, and cataracts. The majority of MVA cases are linked to mutations in BUBR1, a mitotic checkpoint gene required for proper chromosome segregation. Affected patients either have bi-allelic BUBR1 mutations, with one allele harboring a missense mutation and the other a nonsense mutation, or mono-allelic BUBR1 mutations combined with allelic variants that yield low amounts of wild-type BubR1 protein. Parents of MVA patients that carry single allele mutations have mild mitotic defects, but whether they are at risk for any of the pathologies associated with MVA syndrome is unknown. To address this, we engineered a mouse model for the nonsense mutation 2211insGTTA (referred to as GTTA) found in MVA patients with bi-allelic BUBR1 mutations. Here we report that both the median and maximum lifespans of the resulting BubR1+/GTTA mice are significantly reduced. Furthermore, BubR1+/GTTA mice develop several aging-related phenotypes at an accelerated rate, including cataract formation, lordokyphosis, skeletal muscle wasting, impaired exercise ability, and fat loss. BubR1+/GTTA mice develop mild aneuploidies and show enhanced growth of carcinogen-induced tumors. Collectively, these data demonstrate that the BUBR1 GTTA mutation compromises longevity and healthspan, raising the interesting possibility that mono-allelic changes in BUBR1 might contribute to differences in aging rates in the general population. Aging is the main risk factor for the majority of chronic diseases and the leading cause of death and disability in humans. Humans age at different rates, but the molecular genetic basis underlying this phenomenon remains largely unknown. Efforts to understand how we age have focused on genetic changes that extend lifespan or underlie progeroid disorders. One potential progeroid disorder, MVA syndrome, has been associated with mutations in the mitotic regulator BUBR1. Although MVA syndrome is rare due to its recessive nature, individuals carrying heterozygous BUBR1 mutations associated with MVA would be much more prevalent. However, whether such carriers are asymptomatic or at risk of developing aspects of MVA syndrome later in life is unknown. To investigate this, we engineered mice to carry an analogous mutation to the human MVA BUBR1 nonsense mutation 2211insGTTA. We find that these mice have a reduced lifespan and develop several age-related phenotypes at an accelerated rate. These findings suggest that bi-allelic integrity of BUBR1 is a key determinant of healthspan and longevity, and provide a conceptual framework for elucidating differences in aging rates among humans.
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Affiliation(s)
- Tobias Wijshake
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Pathology and Medical Biology, University Medical Center Groningen, Groningen, The Netherlands
| | - Liviu A. Malureanu
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Darren J. Baker
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Karthik B. Jeganathan
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Bart van de Sluis
- Department of Pathology and Medical Biology, University Medical Center Groningen, Groningen, The Netherlands
| | - Jan M. van Deursen
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail:
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36
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Janssen A, Medema RH. Genetic instability: tipping the balance. Oncogene 2012; 32:4459-70. [PMID: 23246960 DOI: 10.1038/onc.2012.576] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2012] [Revised: 10/23/2012] [Accepted: 10/24/2012] [Indexed: 02/06/2023]
Abstract
Tumor cells typically contain a genome that is highly divergent from the genome of normal, non-transformed cells. This genetic divergence is caused by a number of distinct changes that the tumor cell acquires during its transformation from a normal cell into a tumorigenic counterpart. Changes to the genome include mutations, deletions, insertions, and also gross chromosomal aberrations, such as chromosome translocations and whole chromosome gains or losses. This genetic disorder of the tumor cell has complicated the identification of crucial driver mutations that cause cancer. Moreover, the large genetic divergence between different tumors causes them to behave very differently, and makes it difficult to predict response to therapy. In addition, tumor cells are genetically unstable and frequently acquire new mutations and/or gross chromosomal aberrations as they divide. This is beneficial for the overall capacity of a tumor to adapt to changes in its environment, but newly acquired genetic alterations can also compromise the genetic dominance of the tumor cell and thus affect tumor cell viability. Here, we review the mechanisms that can cause gross chromosomal aberrations, and discuss how these affect tumor cell viability.
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Affiliation(s)
- A Janssen
- 1] Division of Cell Biology, Netherlands Cancer Institute, Amsterdam, The Netherlands [2] Department of Medical Oncology and Cancer Genomics Center, University Medical Center Utrecht, Utrecht, The Netherlands
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Increased expression of BubR1 protects against aneuploidy and cancer and extends healthy lifespan. Nat Cell Biol 2012; 15:96-102. [PMID: 23242215 PMCID: PMC3707109 DOI: 10.1038/ncb2643] [Citation(s) in RCA: 188] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2012] [Accepted: 11/05/2012] [Indexed: 02/07/2023]
Abstract
The BubR1 gene encodes for a mitotic regulator that ensures accurate segregation of chromosomes through its role in the mitotic checkpoint and the establishment of proper microtubule-kinetochore attachments. Germline mutations that reduce BubR1 abundance cause aneuploidy, shorten lifespan, and induce premature aging phenotypes and cancer in both humans and mice. Reduced BubR1 expression is also a feature of chronological aging, but whether this age-related decline has biological consequences is unknown. Using a transgenic approach in mice, we show that sustained high expression of BubR1 preserves genomic integrity and reduces tumorigenesis, even in the presence of genetic alterations that strongly promote aneuplodization and cancer, such as oncogenic Ras. We find that BubR1 overabundance exerts its protective effect by correcting mitotic checkpoint impairment and microtubule-kinetochore attachment defects. Furthermore, sustained high expression of BubR1 extends lifespan and delays age-related deterioration and aneuploidy in several tissues. Collectively, these data uncover a generalized function for BubR1 in counteracting defects that cause whole chromosome instability and suggest that modulating BubR1 provides a unique opportunity to extend healthy lifespan.
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38
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Zhang Y, Foreman O, Wigle DA, Kosari F, Vasmatzis G, Salisbury JL, van Deursen J, Galardy PJ. USP44 regulates centrosome positioning to prevent aneuploidy and suppress tumorigenesis. J Clin Invest 2012. [PMID: 23187126 DOI: 10.1172/jci63084] [Citation(s) in RCA: 117] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Most human tumors have abnormal numbers of chromosomes, a condition known as aneuploidy. The mitotic checkpoint is an important mechanism that prevents aneuploidy by restraining the activity of the anaphase-promoting complex (APC). The deubiquitinase USP44 was identified as a key regulator of APC activation; however, the physiological importance of USP44 and its impact on cancer biology are unknown. To clarify the role of USP44 in mitosis, we engineered a mouse lacking Usp44. We found that USP44 regulated the mitotic checkpoint and prevented chromosome lagging. Mice lacking Usp44 were prone to the development of spontaneous tumors, particularly in the lungs. Additionally, USP44 was frequently downregulated in human lung cancer, and low expression correlated with a poor prognosis. USP44 inhibited chromosome segregation errors independent of its role in the mitotic checkpoint by regulating centrosome separation, positioning, and mitotic spindle geometry. These functions required direct binding to the centriole protein centrin. Our data reveal a new role for the ubiquitin system in mitotic spindle regulation and underscore the importance of USP44 in the pathogenesis of human cancer.
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Affiliation(s)
- Ying Zhang
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA
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39
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Schnerch D, Follo M, Felthaus J, Engelhardt M, Wäsch R. Studying proteolysis of cyclin B at the single cell level in whole cell populations. J Vis Exp 2012:e4239. [PMID: 23007658 DOI: 10.3791/4239] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
Equal distribution of chromosomes between the two daughter cells during cell division is a prerequisite for guaranteeing genetic stability. Inaccuracies during chromosome separation are a hallmark of malignancy and associated with progressive disease. The spindle assembly checkpoint (SAC) is a mitotic surveillance mechanism that holds back cells at metaphase until every single chromosome has established a stable bipolar attachment to the mitotic spindle. The SAC exerts its function by interference with the activating APC/C subunit Cdc20 to block proteolysis of securin and cyclin B and thus chromosome separation and mitotic exit. Improper attachment of chromosomes prevents silencing of SAC signaling and causes continued inhibition of APC/C(Cdc20) until the problem is solved to avoid chromosome missegregation, aneuploidy and malignant growths. Most studies that addressed the influence of improper chromosomal attachment on APC/C-dependent proteolysis took advantage of spindle disruption using depolymerizing or microtubule-stabilizing drugs to interfere with chromosomal attachment to microtubules. Since interference with microtubule kinetics can affect the transport and localization of critical regulators, these procedures bear a risk of inducing artificial effects. To study how the SAC interferes with APC/C-dependent proteolysis of cyclin B during mitosis in unperturbed cell populations, we established a histone H2-GFP-based system which allowed the simultaneous monitoring of metaphase alignment of mitotic chromosomes and proteolysis of cyclin B. To depict proteolytic profiles, we generated a chimeric cyclin B reporter molecule with a C-terminal SNAP moiety (Figure 1). In a self-labeling reaction, the SNAP-moiety is able to form covalent bonds with alkylguanine-carriers (SNAP substrate) (Figure 1). SNAP substrate molecules are readily available and carry a broad spectrum of different fluorochromes. Chimeric cyclin B-SNAP molecules become labeled upon addition of the membrane-permeable SNAP substrate to the growth medium (Figure 1). Following the labeling reaction, the cyclin B-SNAP fluorescence intensity drops in a pulse-chase reaction-like manner and fluorescence intensities reflect levels of cyclin B degradation (Figure 1). Our system facilitates the monitoring of mitotic APC/C-dependent proteolysis in large numbers of cells (or several cell populations) in parallel. Thereby, the system may be a valuable tool to identify agents/small molecules that are able to interfere with proteolytic activity at the metaphase to anaphase transition. Moreover, as synthesis of cyclin B during mitosis has recently been suggested as an important mechanism in fostering a mitotic block in mice and humans by keeping cyclin B expression levels stable, this system enabled us to analyze cyclin B proteolysis as one element of a balanced equilibrium.
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Affiliation(s)
- Dominik Schnerch
- Department of Hematology, Oncology and Stem Cell Transplantation, University Medical Center Freiburg
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40
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Hamada M, Malureanu LA, Wijshake T, Zhou W, van Deursen JM. Reprogramming to pluripotency can conceal somatic cell chromosomal instability. PLoS Genet 2012; 8:e1002913. [PMID: 22952451 PMCID: PMC3431347 DOI: 10.1371/journal.pgen.1002913] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Accepted: 07/05/2012] [Indexed: 01/12/2023] Open
Abstract
The discovery that somatic cells are reprogrammable to pluripotency by ectopic expression of a small subset of transcription factors has created great potential for the development of broadly applicable stem-cell-based therapies. One of the concerns regarding the safe use of induced pluripotent stem cells (iPSCs) in therapeutic applications is loss of genomic integrity, a hallmark of various human conditions and diseases, including cancer. Structural chromosome defects such as short telomeres and double-strand breaks are known to limit reprogramming of somatic cells into iPSCs, but whether defects that cause whole-chromosome instability (W-CIN) preclude reprogramming is unknown. Here we demonstrate, using aneuploidy-prone mouse embryonic fibroblasts (MEFs) in which chromosome missegregation is driven by BubR1 or RanBP2 insufficiency, that W-CIN is not a barrier to reprogramming. Unexpectedly, the two W-CIN defects had contrasting effects on iPSC genomic integrity, with BubR1 hypomorphic MEFs almost exclusively yielding aneuploid iPSC clones and RanBP2 hypomorphic MEFs karyotypically normal iPSC clones. Moreover, BubR1-insufficient iPSC clones were karyotypically unstable, whereas RanBP2-insufficient iPSC clones were rather stable. These findings suggest that aneuploid cells can be selected for or against during reprogramming depending on the W-CIN gene defect and present the novel concept that somatic cell W-CIN can be concealed in the pluripotent state. Thus, karyotypic analysis of somatic cells of origin in addition to iPSC lines is necessary for safe application of reprogramming technology. iPSC technology has the potential to revolutionize stem-cell based regenerative medicine and would also allow for the production of patient-specific cells for disease modeling and drug discovery. One of the primary safety concerns of iPSCs is genetic instability, which is associated with cancer and various other diseases and includes abnormalities in both chromosomal structure and number. Whereas certain structural chromosome changes have been shown to preclude somatic cell reprogramming, the effect of whole-chromosome reshuffling on this process is completely unknown. Here we show that BubR1 and RanBP2 hypomorphic MEF lines, which are highly prone to erroneous chromosome segregation due to mitotic checkpoint and DNA decatenation failure, respectively, reprogram to pluripotency with normal efficiency. However, while RanBP2 hypomorphic MEFs yielded karyotypically normal iPSC clones with generally low chromosomal instability rates, BubR1 hypomorphic MEFs almost exclusively yielded aneuploid iPSC clones with high instability rates. These data provide important new insights into the genomic integrity requirements during somatic cell reprogramming, and they establish that the safe application of iPSC technology requires screening of both iPSCs and the iPSC-founder cells for chromosome number instability.
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Affiliation(s)
- Masakazu Hamada
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Liviu A. Malureanu
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Tobias Wijshake
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Wei Zhou
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Jan M. van Deursen
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail:
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41
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Mondal G, Ohashi A, Yang L, Rowley M, Couch FJ. Tex14, a Plk1-regulated protein, is required for kinetochore-microtubule attachment and regulation of the spindle assembly checkpoint. Mol Cell 2012; 45:680-95. [PMID: 22405274 PMCID: PMC3302152 DOI: 10.1016/j.molcel.2012.01.013] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2011] [Revised: 09/14/2011] [Accepted: 01/03/2012] [Indexed: 01/07/2023]
Abstract
Proper assembly of kinetochores (KTs) during mitosis is required for bipolar attachment of spindle microtubules (MTs) and the accumulation of spindle assembly checkpoint (SAC) components. Here we show that testis-expressed protein 14 (Tex14), which has been implicated in midbody function, is recruited to KTs by Plk1 in a Cdk1-dependent manner during early mitosis. Exclusion of Tex14 from kinetochores results in an inability to efficiently localize outer KT components, impaired KT-MT attachment, chromosome congression defects, and whole-chromosome instability. In addition, we demonstrate that phosphorylation of Tex14 by Plk1 during metaphase promotes APC(Cdc20)-mediated Tex14 degradation. Inhibition of this phosphorylation event causes retention of Tex14 at KTs and results in delayed metaphase-to-anaphase transition and chromosome segregation defects. Our findings identify Tex14 as an important mediator of KT structure and function and the fidelity of chromosome separation.
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Affiliation(s)
- Gourish Mondal
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA
| | - Akihiro Ohashi
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA
| | - Lin Yang
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA
| | - Matthew Rowley
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA
| | - Fergus J Couch
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN 55905, USA
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42
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Kang Q, Pomerening JR. Punctuated cyclin synthesis drives early embryonic cell cycle oscillations. Mol Biol Cell 2011; 23:284-96. [PMID: 22130797 PMCID: PMC3258173 DOI: 10.1091/mbc.e11-09-0768] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Cyclin B activates cyclin-dependent kinase 1 (CDK1) at mitosis, but conflicting views have emerged on the dynamics of its synthesis during embryonic cycles, ranging from continuous translation to rapid synthesis during mitosis. Here we show that a CDK1-mediated negative-feedback loop attenuates cyclin production before mitosis. Cyclin B plateaus before peak CDK1 activation, and proteasome inhibition caused minimal accumulation during mitosis. Inhibiting CDK1 permitted continual cyclin B synthesis, whereas adding nondegradable cyclin stalled it. Cycloheximide treatment before mitosis affected neither cyclin levels nor mitotic entry, corroborating this repression. Attenuated cyclin production collaborates with its destruction, since excess cyclin B1 mRNA accelerated cyclin synthesis and caused incomplete proteolysis and mitotic arrest. This repression involved neither adenylation nor the 3' untranslated region, but it corresponded with a shift in cyclin B1 mRNA from polysome to nonpolysome fractions. A pulse-driven CDK1-anaphase-promoting complex (APC) model corroborated these results, revealing reduced cyclin levels during an oscillation and permitting more effective removal. This design also increased the robustness of the oscillator, with lessened sensitivity to changes in cyclin synthesis rate. Taken together, the results of this study underscore that attenuating cyclin synthesis late in interphase improves both the efficiency and robustness of the CDK1-APC oscillator.
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Affiliation(s)
- Qing Kang
- Department of Biology, Indiana University, Bloomington, IN 47405-7003, USA
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43
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Nilsson J. Cdc20 control of cell fate during prolonged mitotic arrest: do Cdc20 protein levels affect cell fate in response to antimitotic compounds? Bioessays 2011; 33:903-9. [PMID: 22045620 DOI: 10.1002/bies.201100094] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The fate of cells arrested in mitosis by antimitotic compounds is complex but is influenced by competition between pathways promoting cell death and pathways promoting mitotic exit. As components of both of these pathways are regulated by Cdc20-dependent degradation, I hypothesize that variations in Cdc20 protein levels, rather than mutations in checkpoint genes, could affect cell fate during prolonged mitotic arrest. This hypothesis is supported by experiments where manipulation of Cdc20 levels affects the response to antimitotic compounds. The observed differences in Cdc20 levels between cell lines likely reflects differences in the rate of synthesis or degradation of the protein; therefore, understanding these pathways at a molecular level could pave the way for modulating the activity of Cdc20, in turn presenting novel therapeutic possibilities.
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Affiliation(s)
- Jakob Nilsson
- Faculty of Health Sciences, Novo Nordisk Foundation Centre for Protein Research, University of Copenhagen, Copenhagen, Denmark.
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44
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Baker DJ, Wijshake T, Tchkonia T, LeBrasseur NK, Childs BG, van de Sluis B, Kirkland JL, van Deursen JM. Clearance of p16Ink4a-positive senescent cells delays ageing-associated disorders. Nature 2011; 479:232-6. [PMID: 22048312 PMCID: PMC3468323 DOI: 10.1038/nature10600] [Citation(s) in RCA: 2438] [Impact Index Per Article: 187.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2011] [Accepted: 09/30/2011] [Indexed: 12/13/2022]
Abstract
Advanced age is the main risk factor for most chronic diseases and functional deficits in humans, but the fundamental mechanisms that drive ageing remain largely unknown, impeding the development of interventions that might delay or prevent age-related disorders and maximize healthy lifespan. Cellular senescence, which halts the proliferation of damaged or dysfunctional cells, is an important mechanism to constrain the malignant progression of tumour cells. Senescent cells accumulate in various tissues and organs with ageing and have been hypothesized to disrupt tissue structure and function because of the components they secrete. However, whether senescent cells are causally implicated in age-related dysfunction and whether their removal is beneficial has remained unknown. To address these fundamental questions, we made use of a biomarker for senescence, p16(Ink4a), to design a novel transgene, INK-ATTAC, for inducible elimination of p16(Ink4a)-positive senescent cells upon administration of a drug. Here we show that in the BubR1 progeroid mouse background, INK-ATTAC removes p16(Ink4a)-positive senescent cells upon drug treatment. In tissues--such as adipose tissue, skeletal muscle and eye--in which p16(Ink4a) contributes to the acquisition of age-related pathologies, life-long removal of p16(Ink4a)-expressing cells delayed onset of these phenotypes. Furthermore, late-life clearance attenuated progression of already established age-related disorders. These data indicate that cellular senescence is causally implicated in generating age-related phenotypes and that removal of senescent cells can prevent or delay tissue dysfunction and extend healthspan.
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Affiliation(s)
- Darren J Baker
- Department of Pediatric and Adolescent Medicine, Mayo Clinic College of Medicine, Rochester, Minnesota 55905, USA
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45
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Hamada M, Haeger A, Jeganathan KB, van Ree JH, Malureanu L, Wälde S, Joseph J, Kehlenbach RH, van Deursen JM. Ran-dependent docking of importin-beta to RanBP2/Nup358 filaments is essential for protein import and cell viability. ACTA ACUST UNITED AC 2011; 194:597-612. [PMID: 21859863 PMCID: PMC3160583 DOI: 10.1083/jcb.201102018] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
RanBP2/Nup358, the major component of the cytoplasmic filaments of the nuclear pore complex (NPC), is essential for mouse embryogenesis and is implicated in both macromolecular transport and mitosis, but its specific molecular functions are unknown. Using RanBP2 conditional knockout mouse embryonic fibroblasts and a series of mutant constructs, we show that transport, rather than mitotic, functions of RanBP2 are required for cell viability. Cre-mediated RanBP2 inactivation caused cell death with defects in M9- and classical nuclear localization signal (cNLS)-mediated protein import, nuclear export signal-mediated protein export, and messenger ribonucleic acid export but no apparent mitotic failure. A short N-terminal RanBP2 fragment harboring the NPC-binding domain, three phenylalanine-glycine motifs, and one Ran-binding domain (RBD) corrected all transport defects and restored viability. Mutation of the RBD within this fragment caused lethality and perturbed binding to Ran guanosine triphosphate (GTP)-importin-β, accumulation of importin-β at nuclear pores, and cNLS-mediated protein import. These data suggest that a critical function of RanBP2 is to capture recycling RanGTP-importin-β complexes at cytoplasmic fibrils to allow for adequate cNLS-mediated cargo import.
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Affiliation(s)
- Masakazu Hamada
- Department of Biochemistry and Molecular Biology and 2 Department of Pediatric and Adolescent Medicine, Mayo Clinic, Rochester, MN 55905, USA
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46
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Zhang Y, van Deursen J, Galardy PJ. Overexpression of ubiquitin specific protease 44 (USP44) induces chromosomal instability and is frequently observed in human T-cell leukemia. PLoS One 2011; 6:e23389. [PMID: 21853124 PMCID: PMC3154946 DOI: 10.1371/journal.pone.0023389] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2011] [Accepted: 07/14/2011] [Indexed: 12/31/2022] Open
Abstract
Cdc20-anaphase promoting complex/cyclosome (Cdc20-APC/C) E3 ubiquitin ligase activity is essential for orderly mitotic progression. The deubiqituinase USP44 was identified as a key regulator of APC/C and has been proposed to suppress Cdc20-APC/C activity by maintaining its association with the inhibitory protein Mad2 until all chromosomes are properly attached to the mitotic spindle. However, this notion has been challenged by data in which a lysine-less mutant of Cdc20 leads to premature anaphase, suggesting that it's ubiquitination is not required for APC/C activation. To further evaluate its role in checkpoint function and chromosome instability, we studied the consequences of over-expression of mouse Usp44 in non-transformed murine embryonic fibroblasts. Here we show that cells with high Usp44 are prone to chromosome segregation errors and aneuploidization. We find that high Usp44 promotes association of Mad2 with Cdc20 and reinforces the mitotic checkpoint. Surprisingly, the APC/C-Cdc20 substrate cyclin B1 is stabilized in G2 when Usp44 is over-expressed, but is degraded with normal kinetics once cells enter mitosis. Furthermore, we show that USP44 expression is elevated in subset of T-cell leukemias. These data are consistent with an important role for USP44 in regulating Cdc20-APC/C activity and suggest that high levels of this enzyme may contribute to the pathogenesis of T-ALL.
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Affiliation(s)
- Ying Zhang
- Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Jan van Deursen
- Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Paul J. Galardy
- Department of Pediatrics and Adolescent Medicine, Mayo Clinic, Rochester, Minnesota, United States of America
- Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, United States of America
- * E-mail:
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47
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Wurzenberger C, Gerlich DW. Phosphatases: providing safe passage through mitotic exit. Nat Rev Mol Cell Biol 2011; 12:469-82. [PMID: 21750572 DOI: 10.1038/nrm3149] [Citation(s) in RCA: 230] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The mitosis-to-interphase transition involves dramatic cellular reorganization from a state that supports chromosome segregation to a state that complies with all functions of an interphase cell. This process, termed mitotic exit, depends on the removal of mitotic phosphorylations from a broad range of substrates. Mitotic exit regulation involves inactivation of mitotic kinases and activation of counteracting protein phosphatases. The key mitotic exit phosphatase in budding yeast, Cdc14, is now well understood. By contrast, in animal cells, it is now emerging that mitotic exit relies on distinct regulatory networks, including the protein phosphatases PP1 and PP2A.
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Affiliation(s)
- Claudia Wurzenberger
- Institute of Biochemistry, Department of Biology, Swiss Federal Institute of Technology Zürich (ETHZ), HPM D11.3, Schafmattstrasse 18, 8093 Zürich, Switzerland
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48
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Regulated inactivation of the spindle assembly checkpoint without functional mitotic spindles. EMBO J 2011; 30:2648-61. [PMID: 21642954 DOI: 10.1038/emboj.2011.176] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2010] [Accepted: 05/09/2011] [Indexed: 12/13/2022] Open
Abstract
The spindle assembly checkpoint (SAC) arrests mitosis until bipolar attachment of spindle microtubules to all chromosomes is accomplished. However, when spindle formation is prevented and the SAC cannot be satisfied, mammalian cells can eventually overcome the mitotic arrest while the checkpoint is still activated. We find that Aspergillus nidulans cells, which are unable to satisfy the SAC, inactivate the checkpoint after a defined period of mitotic arrest. Such SAC inactivation allows normal nuclear reassembly and mitotic exit without DNA segregation. We demonstrate that the mechanisms, which govern such SAC inactivation, require protein synthesis and can occur independently of inactivation of the major mitotic regulator Cdk1/Cyclin B or mitotic exit. Moreover, in the continued absence of spindle function cells transit multiple cell cycles in which the SAC is reactivated each mitosis before again being inactivated. Such cyclic activation and inactivation of the SAC suggests that it is subject to cell-cycle regulation that is independent of bipolar spindle function.
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49
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Matsumura F, Yamakita Y, Yamashiro S. Myosin phosphatase-targeting subunit 1 controls chromatid segregation. J Biol Chem 2011; 286:10825-33. [PMID: 21252232 PMCID: PMC3060533 DOI: 10.1074/jbc.m110.169722] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 12/27/2010] [Indexed: 11/06/2022] Open
Abstract
Myosin phosphatase is a heterotrimeric holoenzyme consisting of myosin phosphatase-targeting subunit 1 (MYPT1), a catalytic subunit of PP1Cβ, and a 20-kDa subunit of an unknown function. We have previously reported that myosin phosphatase also controls mitosis, apparently by antagonizing polo-like kinase 1 (PLK1). Here we found that depletion of MYPT1 by siRNA led to precocious chromatid segregation when HeLa cells were arrested at metaphase by a proteasome inhibitor, MG132, or by Cdc20 depletion. Consistently, cyclin B1 and securin were not degraded, indicating that the chromatid segregation is independent of the anaphase-promoting complex/cyclosome. Precocious segregation induced by MYPT1 depletion requires PLK1 activity because a PLK1 inhibitor, BI-2536, blocked precocious segregation. Furthermore, the expression of an unphosphorylatable mutant of SA2 (SCC3 homologue 2), a subunit of the cohesin complex, prevented precocious chromatid segregation induced by MYPT1 depletion. It has been shown that SA2 at centromeres is protected from phosphorylation by PP2A phosphatase recruited by Shugoshin (Sgo1), whereas SA2 along chromosome arms is phosphorylated by PLK1, leading to SA2 dissociation at chromosome arms. Taken together, our results suggest that hyperactivation of PLK1 caused by MYPT1 reduction could override the counteracting PP2A phosphatase, resulting in precocious chromatid segregation. We propose that SA2 at the centromeres is protected by two phosphatases. One is PP2A directly dephosphorylating SA2, and the other is myosin phosphatase counteracting PLK1.
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Affiliation(s)
- Fumio Matsumura
- From the Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, New Jersey 08854
| | - Yoshihiko Yamakita
- From the Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, New Jersey 08854
| | - Shigeko Yamashiro
- From the Department of Molecular Biology and Biochemistry, Rutgers University, Piscataway, New Jersey 08854
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50
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Short B. A little Cdc20 goes a long way. J Biophys Biochem Cytol 2010. [PMCID: PMC2958485 DOI: 10.1083/jcb.1912if] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Hypomorphic mice reveal new details of Cdc20 and cyclin B1's mitotic activities.
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