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McNamar R, Freeman E, Baylor KN, Fakhouri AM, Huang S, Knutson BA, Rothblum LI. PAF49: An RNA Polymerase I subunit essential for rDNA transcription and stabilization of PAF53. J Biol Chem 2023; 299:104951. [PMID: 37356716 PMCID: PMC10365956 DOI: 10.1016/j.jbc.2023.104951] [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: 04/04/2023] [Revised: 05/30/2023] [Accepted: 06/09/2023] [Indexed: 06/27/2023] Open
Abstract
The application of genetic and biochemical techniques in yeast has informed our knowledge of transcription in mammalian cells. Such systems have allowed investigators to determine whether a gene was essential and to determine its function in rDNA transcription. However, there are significant differences in the nature of the transcription factors essential for transcription by Pol I in yeast and mammalian cells, and yeast RNA polymerase I contains 14 subunits while mammalian polymerase contains 13 subunits. We previously reported the adaptation of the auxin-dependent degron that enabled a combination of a "genetics-like" approach and biochemistry to study mammalian rDNA transcription. Using this system, we studied the mammalian orthologue of yeast RPA34.5, PAF49, and found that it is essential for rDNA transcription and cell division. The auxin-induced degradation of PAF49 induced nucleolar stress and the accumulation of P53. Interestingly, the auxin-induced degradation of AID-tagged PAF49 led to the degradation of its binding partner, PAF53, but not vice versa. A similar pattern of co-dependent expression was also found when we studied the non-essential, yeast orthologues. An analysis of the domains of PAF49 that are essential for rDNA transcription demonstrated a requirement for both the dimerization domain and an "arm" of PAF49 that interacts with PolR1B. Further, we demonstrate this interaction can be disrupted to inhibit Pol I transcription in normal and cancer cells which leads to the arrest of normal cells and cancer cell death. In summary, we have shown that both PAF53 and PAF49 are necessary for rDNA transcription and cell growth.
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Affiliation(s)
- Rachel McNamar
- Department of Cell Biology, University of Oklahoma College of Medicine, Oklahoma City, Oklahoma, USA
| | - Emma Freeman
- Department of Cell and Development Biology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Kairo N Baylor
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Aula M Fakhouri
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Sui Huang
- Department of Cell and Development Biology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - Bruce A Knutson
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York, USA
| | - Lawrence I Rothblum
- Department of Cell Biology, University of Oklahoma College of Medicine, Oklahoma City, Oklahoma, USA.
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2
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Survival and functional recovery of primary cortical neurons exposed to actinomycin D. Biochem Biophys Res Commun 2022; 636:132-139. [DOI: 10.1016/j.bbrc.2022.10.083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 10/24/2022] [Indexed: 11/20/2022]
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3
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Schmidt HB, Jaafar ZA, Wulff BE, Rodencal JJ, Hong K, Aziz-Zanjani MO, Jackson PK, Leonetti MD, Dixon SJ, Rohatgi R, Brandman O. Oxaliplatin disrupts nucleolar function through biophysical disintegration. Cell Rep 2022; 41:111629. [DOI: 10.1016/j.celrep.2022.111629] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 08/28/2022] [Accepted: 10/18/2022] [Indexed: 11/09/2022] Open
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4
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mTOR- and LARP1-dependent regulation of TOP mRNA poly(A) tail and ribosome loading. Cell Rep 2022; 41:111548. [DOI: 10.1016/j.celrep.2022.111548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 08/30/2022] [Accepted: 09/30/2022] [Indexed: 11/20/2022] Open
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5
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Snyers L, Laffer S, Löhnert R, Weipoltshammer K, Schöfer C. CX-5461 causes nucleolar compaction, alteration of peri- and intranucleolar chromatin arrangement, an increase in both heterochromatin and DNA damage response. Sci Rep 2022; 12:13972. [PMID: 35978024 PMCID: PMC9385865 DOI: 10.1038/s41598-022-17923-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 08/02/2022] [Indexed: 11/09/2022] Open
Abstract
In this study, we characterize the changes in nucleolar morphology and its dynamics induced by the recently introduced compound CX-5461, an inhibitor of ribosome synthesis. Time-lapse imaging, immunofluorescence and ultrastructural analysis revealed that exposure of cells to CX-5461 has a profound impact on their nucleolar morphology and function: nucleoli acquired a compact, spherical shape and display enlarged, ring-like masses of perinucleolar condensed chromatin. Tunnels consisting of chromatin developed as transient structures running through nucleoli. Nucleolar components involved in rRNA transcription, fibrillar centres and dense fibrillar component with their major constituents ribosomal DNA, RNA polymerase I and fibrillarin maintain their topological arrangement but become reduced in number and move towards the nucleolar periphery. Nucleolar changes are paralleled by an increased amount of the DNA damage response indicator γH2AX and DNA unwinding enzyme topoisomerase I in nucleoli and the perinucleolar area suggesting that CX-5461 induces torsional stress and DNA damage in rDNA. This is corroborated by the irreversibility of the observed altered nucleolar phenotypes. We demonstrate that incubation with CX-5461, apart from leading to specific morphological alterations, increases senescence and decreases cell replication. We discuss that these alterations differ from those observed with other drugs interfering with nucleolar functions.
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Affiliation(s)
- Luc Snyers
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Schwarzspanierstr. 17, 1090, Vienna, Austria
| | - Sylvia Laffer
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Schwarzspanierstr. 17, 1090, Vienna, Austria
| | - Renate Löhnert
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Schwarzspanierstr. 17, 1090, Vienna, Austria
| | - Klara Weipoltshammer
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Schwarzspanierstr. 17, 1090, Vienna, Austria
| | - Christian Schöfer
- Department for Cell and Developmental Biology, Center for Anatomy and Cell Biology, Medical University of Vienna, Schwarzspanierstr. 17, 1090, Vienna, Austria.
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Tagliaferro M, Rosa P, Bellenchi GC, Bastianelli D, Trotta R, Tito C, Fazi F, Calogero A, Ponti D. Nucleolar localization of the ErbB3 receptor as a new target in glioblastoma. BMC Mol Cell Biol 2022; 23:13. [PMID: 35255831 PMCID: PMC8900349 DOI: 10.1186/s12860-022-00411-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 02/14/2022] [Indexed: 12/12/2022] Open
Abstract
Background The nucleolus is a subnuclear, non-membrane bound domain that is the hub of ribosome biogenesis and a critical regulator of cell homeostasis. Rapid growth and division of cells in tumors are correlated with intensive nucleolar metabolism as a response to oncogenic factors overexpression. Several members of the Epidermal Growth Factor Receptor (EGFR) family, have been identified in the nucleus and nucleolus of many cancer cells, but their function in these compartments remains unexplored. Results We focused our research on the nucleolar function that a specific member of EGFR family, the ErbB3 receptor, plays in glioblastoma, a tumor without effective therapies. Here, Neuregulin 1 mediated proliferative stimuli, promotes ErbB3 relocalization from the nucleolus to the cytoplasm and increases pre-rRNA synthesis. Instead ErbB3 silencing or nucleolar stress reduce cell proliferation and affect cell cycle progression. Conclusions These data point to the existence of an ErbB3-mediated non canonical pathway that glioblastoma cells use to control ribosomes synthesis and cell proliferation. These results highlight the potential role for the nucleolar ErbB3 receptor, as a new target in glioblastoma. Supplementary Information The online version contains supplementary material available at 10.1186/s12860-022-00411-y.
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Affiliation(s)
- Marzia Tagliaferro
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome La Sapienza, Corso della Repubblica 79, 04100, Latina, Italy
| | - Paolo Rosa
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome La Sapienza, Corso della Repubblica 79, 04100, Latina, Italy
| | - Gian Carlo Bellenchi
- Institute of Genetics and Biophysics "Adriano Buzzati Traverso" CNR, 80131, Naples, Italy.,Fondazione Santa Lucia IRCCS, 00143, Rome, Italy.,Department of Systems Medicine, University of Tor Vergata, 00133, Rome, Italy
| | | | - Rosa Trotta
- Laboratory of Tumor Inflammation and Angiogenesis, Center for Cancer Biology (CCB), VIB, Leuven, Belgium.,Laboratory of Tumor Inflammation and Angiogenesis, and Department of Oncology, KU Leuven, Leuven, Belgium
| | - Claudia Tito
- Department of Anatomical, Histological, Forensic and Orthopaedic Sciences, Sapienza University of Rome, 00185, Rome, Italy
| | - Francesco Fazi
- Department of Anatomical, Histological, Forensic and Orthopaedic Sciences, Sapienza University of Rome, 00185, Rome, Italy
| | - Antonella Calogero
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome La Sapienza, Corso della Repubblica 79, 04100, Latina, Italy.,Istituto Chirurgico Ortopedico Traumatologico, 04100, Latina, Italy
| | - Donatella Ponti
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome La Sapienza, Corso della Repubblica 79, 04100, Latina, Italy. .,Laboratory of Tumor Inflammation and Angiogenesis, Center for Cancer Biology (CCB), VIB, Leuven, Belgium.
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Zhao Y, Wang L, Sun X, Bao Y, Liu H, Zhao Y. Inhibition of ribosome biogenesis by actinomycin D affects Arabidopsis root development. Biochem Biophys Res Commun 2021; 588:61-67. [PMID: 34952471 DOI: 10.1016/j.bbrc.2021.12.030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 12/09/2021] [Indexed: 12/14/2022]
Abstract
Actinomycin D has been reported to selectively inhibit rRNA synthesis and ribosome biogenesis, induce G2 checkpoint of cell cycle arrest in HeLa cells. In Arabidopsis, actinomycin D was also used as agent to preferentially inhibit the ribosome biosynthesis and ribosomal function. However, the function of actinomycin D on Arabidopsis root development remains to be elucidated. In this study, we exposed Arabidopsis seedlings to actinomycin D with the aim of evaluating the effects of ribosome biogenesis on root development. The results demonstrated that actinomycin D inhibited Arabidopsis root growth by reduced meristematic activity in a dose dependent manner. Exposure to actinomycin D decreased the expression of WOX5 and key stem cell niche-defining transcription factors SHR and PLT1, thus the loss function of QC identity and stem cell niche maintenance. In addition, dead cells were observed after actinomycin D treatment in root stele initials and DNA damage response was constitutively activated. Collectively, we propose that ribosome biogenesis plays key role in primary root growth through maintenance of root stem cell niche and DNA damage response in Arabidopsis.
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Affiliation(s)
- Yanxue Zhao
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China; State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, People's Republic of China
| | - Lei Wang
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, People's Republic of China
| | - Xuwu Sun
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, People's Republic of China
| | - Yiqun Bao
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China
| | - Hao Liu
- State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, People's Republic of China.
| | - Yanxue Zhao
- College of Life Sciences, Nanjing Agricultural University, Nanjing, 210095, People's Republic of China; State Key Laboratory of Crop Stress Adaptation and Improvement, School of Life Sciences, Henan University, Kaifeng, 475004, People's Republic of China.
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8
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de la Torre P, Fernández-de la Torre M, Flores AI. Premature senescence of placental decidua cells as a possible cause of miscarriage produced by mycophenolic acid. J Biomed Sci 2021; 28:3. [PMID: 33397374 PMCID: PMC7780668 DOI: 10.1186/s12929-020-00704-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 12/23/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Successful pregnancy is supported by a healthy maternal-fetal interface (i.e., the decidual tissues) which holds the conceptus and safeguards it against stressors from the beginning of pregnancy. Any disturbance of this interface can presumably lead to the loss of pregnancy. The use of the immunosuppressive drug mycophenolic acid (MPA) should be discontinued in pregnancy given its abortive and embryotoxic effects. Direct teratogenic effects have been observed in mammalian embryos cultured in MPA, but the underlying mechanisms of abortion by MPA are less understood. METHODS Decidual stromal cells isolated from human placentas are cultured in the presence of clinically relevant doses of MPA. Data regarding the effects of MPA on the proliferation and viability of decidua cultures are first analysed and then, molecular pathways contributing to these effects are unravelled. RESULTS MPA treatment of decidual stromal cells results in loss of proliferation capacity and a decrease in the viability of decidua cultures. The molecular pathways involved in the effects of MPA on decidual stromal cells are a reduction in pre-rRNA synthesis and subsequent disruption of the nucleolus. The nucleolar stress stabilizes p53, which in turn, leads to a p21-mediated cell cycle arrest in late S and G2 phases, preventing the progression of the decidua cells into the mitosis. Furthermore, MPA does not induce apoptosis but activate mechanisms of autophagy and senescence in decidual stromal cells. CONCLUSION The irreversible growth arrest of decidua cells, whose role in the maintenance of the pregnancy microenvironment is known, may be one cause of miscarriage in MPA treated pregnant women.
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Affiliation(s)
- Paz de la Torre
- Grupo de Medicina Regenerativa, Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Avda. Cordoba s/n 28041, Madrid, Spain
| | - Miguel Fernández-de la Torre
- Grupo de Enfermedades Raras, Mitocondriales y Neuromusculares, Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Avda. Cordoba s/n 28041, Madrid, Spain
| | - Ana I Flores
- Grupo de Medicina Regenerativa, Instituto de Investigación Sanitaria Hospital 12 de Octubre (imas12), Avda. Cordoba s/n 28041, Madrid, Spain.
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9
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Gueiderikh A, Maczkowiak-Chartois F, Rouvet G, Souquère-Besse S, Apcher S, Diaz JJ, Rosselli F. Fanconi anemia A protein participates in nucleolar homeostasis maintenance and ribosome biogenesis. SCIENCE ADVANCES 2021; 7:7/1/eabb5414. [PMID: 33523834 PMCID: PMC7775781 DOI: 10.1126/sciadv.abb5414] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Accepted: 10/28/2020] [Indexed: 05/22/2023]
Abstract
Fanconi anemia (FA), the most common inherited bone marrow failure and leukemia predisposition syndrome, is generally attributed to alterations in DNA damage responses due to the loss of function of the DNA repair and replication rescue activities of the FANC pathway. Here, we report that FANCA deficiency, whose inactivation has been identified in two-thirds of FA patients, is associated with nucleolar homeostasis loss, mislocalization of key nucleolar proteins, including nucleolin (NCL) and nucleophosmin 1 (NPM1), as well as alterations in ribosome biogenesis and protein synthesis. FANCA coimmunoprecipitates with NCL and NPM1 in a FANCcore complex-independent manner and, unique among the FANCcore complex proteins, associates with ribosomal subunits, influencing the stoichiometry of the translational machineries. In conclusion, we have identified unexpected nucleolar and translational consequences specifically associated with FANCA deficiency that appears to be involved in both DNA damage and nucleolar stress responses, challenging current hypothesis on FA physiopathology.
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Affiliation(s)
- Anna Gueiderikh
- CNRS-UMR9019, Équipe labellisée "La Ligue contre le Cancer," 94805 Villejuif, France
- Gustave Roussy Cancer Center, 94805 Villejuif, France
- Université Paris-Saclay-Paris Sud, Orsay, France
| | - Frédérique Maczkowiak-Chartois
- CNRS-UMR9019, Équipe labellisée "La Ligue contre le Cancer," 94805 Villejuif, France
- Gustave Roussy Cancer Center, 94805 Villejuif, France
- Université Paris-Saclay-Paris Sud, Orsay, France
| | - Guillaume Rouvet
- CNRS-UMR9019, Équipe labellisée "La Ligue contre le Cancer," 94805 Villejuif, France
- Gustave Roussy Cancer Center, 94805 Villejuif, France
- Université Paris-Saclay-Paris Sud, Orsay, France
| | - Sylvie Souquère-Besse
- Gustave Roussy Cancer Center, 94805 Villejuif, France
- Université Paris-Saclay-Paris Sud, Orsay, France
- CNRS-UMS3655, 94805 Villejuif, France
| | - Sébastien Apcher
- Gustave Roussy Cancer Center, 94805 Villejuif, France
- Université Paris-Saclay-Paris Sud, Orsay, France
- INSERM-UMR1015, 94805 Villejuif, France
| | - Jean-Jacques Diaz
- Université Lyon, Université Claude Bernard Lyon 1, Inserm 1052, CNRS 5286, Centre Léon Bérard, Cancer Research Center of Lyon, 69373 Lyon cedex 08, France
| | - Filippo Rosselli
- CNRS-UMR9019, Équipe labellisée "La Ligue contre le Cancer," 94805 Villejuif, France.
- Gustave Roussy Cancer Center, 94805 Villejuif, France
- Université Paris-Saclay-Paris Sud, Orsay, France
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Zhang W, Cheng W, Parlato R, Guo X, Cui X, Dai C, Xu L, Zhu J, Zhu M, Luo K, Zhang W, Dong B, Wang J, Jiang F. Nucleolar stress induces a senescence-like phenotype in smooth muscle cells and promotes development of vascular degeneration. Aging (Albany NY) 2020; 12:22174-22198. [PMID: 33146634 PMCID: PMC7695416 DOI: 10.18632/aging.104094] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/31/2020] [Indexed: 12/24/2022]
Abstract
Senescence of smooth muscle cells (SMCs) has a crucial role in the pathogenesis of abdominal aortic aneurysm (AAA), a disease of vascular degeneration. Perturbation of cellular ribosomal DNA (rDNA) transcription triggers nucleolar stress response. Previously we demonstrated that induction of nucleolar stress in SMCs elicited cell cycle arrest via the ataxia-telangiectasia mutated (ATM)/ATM- and Rad3-related (ATR)-p53 axis. However, the specific roles of nucleolar stress in vascular degeneration remain unexplored. In the present study, we demonstrated for the first time that in both human and animal AAA tissues, there were non-coordinated changes in the expression of RNA polymerase I machinery components, including a downregulation of transcription initiation factor-IA (TIF-IA). Genetic deletion of TIF-IA in SMCs in mice (smTIF-IA-/-) caused spontaneous aneurysm-like lesions in the aorta. In vitro, induction of nucleolar stress triggered a non-canonical DNA damage response, leading to p53 phosphorylation and a senescence-like phenotype in SMCs. In human AAA tissues, there was increased nucleolar stress in medial cells, accompanied by localized DNA damage response within the nucleolar compartment. Our data suggest that perturbed rDNA transcription and induction of nucleolar stress contribute to the pathogenesis of AAA. Moreover, smTIF-IA-/- mice may be a novel animal model for studying spontaneous AAA-like vascular degenerations.
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Affiliation(s)
- Wenjing Zhang
- Department of Physiology and Pathophysiology, School of Basic Medicine, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China.,Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, Jinan, China
| | - Wen Cheng
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, and The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China
| | - Rosanna Parlato
- Institute of Applied Physiology, University of Ulm, Ulm, Germany.,Institute of Anatomy and Cell Biology, University of Heidelberg, Heidelberg, Germany
| | - Xiaosun Guo
- Department of Physiology and Pathophysiology, School of Basic Medicine, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China
| | - Xiaopei Cui
- Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, Jinan, China
| | - Chaochao Dai
- Department of Physiology and Pathophysiology, School of Basic Medicine, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China.,Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, Jinan, China
| | - Lei Xu
- Department of Vascular Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Jiankang Zhu
- Department of General Surgery, The First Affiliated Hospital of Shandong First Medical University, Jinan, China
| | - Min Zhu
- Department of Transplant Surgery, Qilu Hospital of Shandong University, Jinan, China
| | - Kun Luo
- Department of Vascular Surgery, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, China
| | - Wencheng Zhang
- Key Laboratory of Cardiovascular Remodeling and Function Research, Chinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical Sciences, and The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of Cardiology, Qilu Hospital of Shandong University, Jinan, China
| | - Bo Dong
- Department of Cardiology, Shandong Provincial Hospital Affiliated to Shandong University, Jinan, Shandong Province, China
| | - Jianli Wang
- Department of Physiology and Pathophysiology, School of Basic Medicine, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China.,Current address: Department of Obstetrics and Gynecology, Qilu Hospital of Shandong University, Jinan, China
| | - Fan Jiang
- Department of Physiology and Pathophysiology, School of Basic Medicine, Cheeloo College of Medicine, Shandong University, Jinan, Shandong Province, China.,Key Laboratory of Cardiovascular Proteomics of Shandong Province, Qilu Hospital of Shandong University, Jinan, China
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11
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Frequent Germline and Somatic Single Nucleotide Variants in the Promoter Region of the Ribosomal RNA Gene in Japanese Lung Adenocarcinoma Patients. Cells 2020; 9:cells9112409. [PMID: 33153169 PMCID: PMC7692307 DOI: 10.3390/cells9112409] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 10/28/2020] [Accepted: 10/29/2020] [Indexed: 12/25/2022] Open
Abstract
Ribosomal RNA (rRNA), the most abundant non-coding RNA species, is a major component of the ribosome. Impaired ribosome biogenesis causes the dysfunction of protein synthesis and diseases called “ribosomopathies,” including genetic disorders with cancer risk. However, the potential role of rRNA gene (rDNA) alterations in cancer is unknown. We investigated germline and somatic single-nucleotide variants (SNVs) in the rDNA promoter region (positions −248 to +100, relative to the transcription start site) in 82 lung adenocarcinomas (LUAC). Twenty-nine tumors (35.4%) carried germline SNVs, and eight tumors (9.8%) harbored somatic SNVs. Interestingly, the presence of germline SNVs between positions +1 and +100 (n = 12; 14.6%) was associated with significantly shorter recurrence-free survival (RFS) and overall survival (OS) by univariate analysis (p < 0.05, respectively), and was an independent prognostic factor for RFS and OS by multivariate analysis. LUAC cell line PC9, carrying rDNA promoter SNV at position +49, showed significantly higher ribosome biogenesis than H1650 cells without SNV. Upon nucleolar stress induced by actinomycin D, PC9 retained significantly higher ribosome biogenesis than H1650. These results highlight the possible functional role of SNVs at specific sites of the rDNA promoter region in ribosome biogenesis, the progression of LUAC, and their potential prognostic value.
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12
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Hiregange D, Naick H, Rao BJ. ATR signalling mediates the prosurvival function of phospho-NPM against PIDDosome mediated cell death. Cell Signal 2020; 71:109602. [DOI: 10.1016/j.cellsig.2020.109602] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Accepted: 03/14/2020] [Indexed: 12/14/2022]
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13
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Duan T, Green N, Tootle TL, Geyer PK. Nuclear architecture as an intrinsic regulator of Drosophila female germline stem cell maintenance. CURRENT OPINION IN INSECT SCIENCE 2020; 37:30-38. [PMID: 32087561 PMCID: PMC7089816 DOI: 10.1016/j.cois.2019.11.007] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 11/08/2019] [Accepted: 11/13/2019] [Indexed: 05/08/2023]
Abstract
Homeostasis of Drosophila germline stem cells (GSC) depends upon the integration of intrinsic and extrinsic signals. This review highlights emerging data that support nuclear architecture as an intrinsic regulator of GSC maintenance and germ cell differentiation. Here, we focus on the nuclear lamina (NL) and the nucleolus, two compartments that undergo alterations in composition upon germ cell differentiation. Loss of NL or nucleolar components leads to GSC loss, resulting from activation of GSC quality control checkpoint pathways. We suggest that the NL and nucleolus integrate signals needed for the switch between GSC maintenance and germ cell differentiation, and propose regulation of nuclear actin pools as one mechanism that connects these compartments.
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Affiliation(s)
- Tingting Duan
- Departments of Biochemistry, University of Iowa, College of Medicine, Iowa City, IA 52242, USA
| | - Nicole Green
- Anatomy and Cell Biology, University of Iowa, College of Medicine, Iowa City, IA 52242, USA
| | - Tina L Tootle
- Anatomy and Cell Biology, University of Iowa, College of Medicine, Iowa City, IA 52242, USA
| | - Pamela K Geyer
- Departments of Biochemistry, University of Iowa, College of Medicine, Iowa City, IA 52242, USA.
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14
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McNamar R, Abu-Adas Z, Rothblum K, Knutson BA, Rothblum LI. Conditional depletion of the RNA polymerase I subunit PAF53 reveals that it is essential for mitosis and enables identification of functional domains. J Biol Chem 2019; 294:19907-19922. [PMID: 31727736 PMCID: PMC6937585 DOI: 10.1074/jbc.ra119.009902] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 11/05/2019] [Indexed: 12/24/2022] Open
Abstract
Our knowledge of the mechanism of rDNA transcription has benefited from the combined application of genetic and biochemical techniques in yeast. Nomura's laboratory (Nogi, Y., Vu, L., and Nomura, M. (1991) Proc. Natl. Acad. Sci. U.S.A. 88, 7026-7030 and Nogi, Y., Yano, R., and Nomura, M. (1991) Proc. Natl. Acad. Sci. U.S.A. 88, 3962-3966) developed a system in yeast to identify genes essential for ribosome biogenesis. Such systems have allowed investigators to determine whether a gene was essential and to determine its function in rDNA transcription. However, there are significant differences in both the structures and components of the transcription apparatus and the patterns of regulation between mammals and yeast. Thus, there are significant deficits in our understanding of mammalian rDNA transcription. We have developed a system combining CRISPR/Cas9 and an auxin-inducible degron that enables combining a "genetics-like"approach with biochemistry to study mammalian rDNA transcription. We now show that the mammalian orthologue of yeast RPA49, PAF53, is required for rDNA transcription and mitotic growth. We have studied the domains of the protein required for activity. We have found that the C-terminal, DNA-binding domain (tandem-winged helix), the heterodimerization, and the linker domain were essential. Analysis of the linker identified a putative helix-turn-helix (HTH) DNA-binding domain. This HTH constitutes a second DNA-binding domain within PAF53. The HTH of the yeast and mammalian orthologues is essential for function. In summary, we show that an auxin-dependent degron system can be used to rapidly deplete nucleolar proteins in mammalian cells, that PAF53 is necessary for rDNA transcription and cell growth, and that all three PAF53 domains are necessary for its function.
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Affiliation(s)
- Rachel McNamar
- Department of Cell Biology, University of Oklahoma College of Medicine, Oklahoma City, Oklahoma 73104
| | - Zakaria Abu-Adas
- Department of Cell Biology, University of Oklahoma College of Medicine, Oklahoma City, Oklahoma 73104
| | - Katrina Rothblum
- Department of Cell Biology, University of Oklahoma College of Medicine, Oklahoma City, Oklahoma 73104
| | - Bruce A Knutson
- Department of Biochemistry and Molecular Biology, SUNY Upstate Medical University, Syracuse, New York 13210
| | - Lawrence I Rothblum
- Department of Cell Biology, University of Oklahoma College of Medicine, Oklahoma City, Oklahoma 73104
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15
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He JS, Soo P, Evers M, Parsons KM, Hein N, Hannan KM, Hannan RD, George AJ. High-Content Imaging Approaches to Quantitate Stress-Induced Changes in Nucleolar Morphology. Assay Drug Dev Technol 2019; 16:320-332. [PMID: 30148664 DOI: 10.1089/adt.2018.861] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The nucleolus is a dynamic subnuclear compartment that has a number of different functions, but its primary role is to coordinate the production and assembly of ribosomes. For well over 100 years, pathologists have used changes in nucleolar number and size to stage diseases such as cancer. New information about the nucleolus' broader role within the cell is leading to the development of drugs which directly target its structure as therapies for disease. Traditionally, it has been difficult to develop high-throughput image analysis pipelines to measure nucleolar changes due to the broad range of morphologies observed. In this study, we describe a simple high-content image analysis algorithm using Harmony software (PerkinElmer), with a PhenoLOGIC™ machine-learning component, that can measure and classify three different nucleolar morphologies based on nucleolin and fibrillarin staining ("normal," "peri-nucleolar rings" and "dispersed"). We have utilized this algorithm to determine the changes in these classes of nucleolar morphologies over time with drugs known to alter nucleolar structure. This approach could be further adapted to include other parameters required for the identification of new therapies that directly target the nucleolus.
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Affiliation(s)
- Jin-Shu He
- 1 ANU Centre for Therapeutic Discovery, The Australian National University , Acton, Australia
| | - Priscilla Soo
- 2 ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University , Acton, Australia
| | - Maurits Evers
- 2 ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University , Acton, Australia
| | - Kate M Parsons
- 1 ANU Centre for Therapeutic Discovery, The Australian National University , Acton, Australia
| | - Nadine Hein
- 2 ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University , Acton, Australia
| | - Katherine M Hannan
- 2 ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University , Acton, Australia .,3 Department of Biochemistry and Molecular Biology, University of Melbourne , Parkville, Australia
| | - Ross D Hannan
- 2 ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University , Acton, Australia .,3 Department of Biochemistry and Molecular Biology, University of Melbourne , Parkville, Australia .,4 Sir Peter MacCallum Department of Oncology, University of Melbourne , Parkville, Australia .,5 Department of Biochemistry and Molecular Biology, University of Melbourne , Parkville, Australia .,6 Department of Biochemistry and Molecular Biology, Monash University , Clayton, Australia .,7 School of Biomedical Sciences, University of Queensland , St Lucia, Australia
| | - Amee J George
- 1 ANU Centre for Therapeutic Discovery, The Australian National University , Acton, Australia .,2 ACRF Department of Cancer Biology and Therapeutics, The John Curtin School of Medical Research, The Australian National University , Acton, Australia .,7 School of Biomedical Sciences, University of Queensland , St Lucia, Australia .,8 Department of Clinical Pathology, University of Melbourne , Parkville, Australia
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16
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Carotenuto P, Pecoraro A, Palma G, Russo G, Russo A. Therapeutic Approaches Targeting Nucleolus in Cancer. Cells 2019; 8:E1090. [PMID: 31527430 PMCID: PMC6770360 DOI: 10.3390/cells8091090] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2019] [Revised: 09/08/2019] [Accepted: 09/13/2019] [Indexed: 01/08/2023] Open
Abstract
The nucleolus is a distinct sub-cellular compartment structure in the nucleus. First observed more than 200 years ago, the nucleolus is detectable by microscopy in eukaryotic cells and visible during the interphase as a sub-nuclear structure immersed in the nucleoplasm, from which it is not separated from any membrane. A huge number of studies, spanning over a century, have identified ribosome biogenesis as the main function of the nucleolus. Recently, novel functions, independent from ribosome biogenesis, have been proposed by several proteomic, genomic, and functional studies. Several works have confirmed the non-canonical role for nucleoli in regulating important cellular processes including genome stability, cell-cycle control, the cellular senescence, stress responses, and biogenesis of ribonucleoprotein particles (RNPs). Many authors have shown that both canonical and non-canonical functions of the nucleolus are associated with several cancer-related processes. The association between the nucleolus and cancer, first proposed by cytological and histopathological studies showing that the number and shape of nucleoli are commonly altered in almost any type of cancer, has been confirmed at the molecular level by several authors who demonstrated that numerous mechanisms occurring in the nucleolus are altered in tumors. Recently, therapeutic approaches targeting the nucleolus in cancer have started to be considered as an emerging "hallmark" of cancer and several therapeutic interventions have been developed. This review proposes an up-to-date overview of available strategies targeting the nucleolus, focusing on novel targeted therapeutic approaches. Finally, a target-based classification of currently available treatment will be proposed.
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Affiliation(s)
- Pietro Carotenuto
- The Institute of Cancer Research, Cancer Therapeutic Unit, London SM2 5NG, UK.
- Telethon Institute of Genetics and Medicine (TIGEM), Pozzuoli 80078, Italy.
| | - Annalisa Pecoraro
- Department of Pharmacy, School of Medicine, University of Naples Federico II, Via Domenico Montesano 49, 80131 Naples, Italy.
| | - Gaetano Palma
- Department of Advanced Biomedical Science, School of Medicine, University of Naples Federico II, 80131 Naples, Italy.
| | - Giulia Russo
- Department of Pharmacy, School of Medicine, University of Naples Federico II, Via Domenico Montesano 49, 80131 Naples, Italy.
| | - Annapina Russo
- Department of Pharmacy, School of Medicine, University of Naples Federico II, Via Domenico Montesano 49, 80131 Naples, Italy.
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17
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Bi X, Ye Q, Li D, Peng Q, Wang Z, Wu X, Zhang Y, Zhang Q, Jiang F. Inhibition of nucleolar stress response by Sirt1: A potential mechanism of acetylation-independent regulation of p53 accumulation. Aging Cell 2019; 18:e12900. [PMID: 30623565 PMCID: PMC6413664 DOI: 10.1111/acel.12900] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2018] [Revised: 11/28/2018] [Accepted: 12/08/2018] [Indexed: 02/04/2023] Open
Abstract
The mammalian Sirt1 deacetylase is generally thought to be a nuclear protein, but some pilot studies have suggested that Sirt1 may also be involved in orchestrating nucleolar functions. Here, we show that nucleolar stress response is a ubiquitous cellular reaction that can be induced by different types of stress conditions, and Sirt1 is an endogenous suppressor of nucleolar stress response. Using stable isotope labeling by amino acids in cell culture approach, we have identified a physical interaction of between Sirt1 and the nucleolar protein nucleophosmin, and this protein-protein interaction appears to be necessary for Sirt1 inhibition on nucleolar stress, whereas the deacetylase activity of Sirt1 is not strictly required. Based on the reported prerequisite role of nucleolar stress response in stress-induced p53 protein accumulation, we have also provided evidence suggesting that Sirt1-mediated inhibition on nucleolar stress response may represent a novel mechanism by which Sirt1 can modulate intracellular p53 accumulation independent of lysine deacetylation. This process may represent an alternative mechanism by which Sirt1 regulates functions of the p53 pathway.
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Affiliation(s)
- Xiaolei Bi
- School of Basic MedicineShandong UniversityJinanShandong ProvinceChina
- Key Laboratory of Cardiovascular Remodeling and Function ResearchChinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical SciencesJinanChina
- The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of CardiologyQilu Hospital of Shandong UniversityJinanChina
- Present address:
Department of CardiologyQingdao Municipal HospitalQingdaoShandong ProvinceChina
| | - Qing Ye
- School of Basic MedicineShandong UniversityJinanShandong ProvinceChina
- Key Laboratory of Cardiovascular Remodeling and Function ResearchChinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical SciencesJinanChina
- The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of CardiologyQilu Hospital of Shandong UniversityJinanChina
| | - Daoyuan Li
- National Glycoengineering Research CenterShandong UniversityJinanChina
| | - Qisheng Peng
- Key Laboratory of Zoonosis ResearchJilin UniversityChangchunJilin ProvinceChina
| | - Zhe Wang
- Division of Endocrinology and MetabolismShandong Provincial Hospital affiliated to Shandong UniversityJinanChina
| | - Xiao Wu
- Key Laboratory of Cardiovascular Remodeling and Function ResearchChinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical SciencesJinanChina
- The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of CardiologyQilu Hospital of Shandong UniversityJinanChina
| | - Yun Zhang
- Key Laboratory of Cardiovascular Remodeling and Function ResearchChinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical SciencesJinanChina
- The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of CardiologyQilu Hospital of Shandong UniversityJinanChina
| | - Qunye Zhang
- Key Laboratory of Cardiovascular Remodeling and Function ResearchChinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical SciencesJinanChina
- The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of CardiologyQilu Hospital of Shandong UniversityJinanChina
| | - Fan Jiang
- School of Basic MedicineShandong UniversityJinanShandong ProvinceChina
- Key Laboratory of Cardiovascular Remodeling and Function ResearchChinese Ministry of Education, Chinese National Health Commission and Chinese Academy of Medical SciencesJinanChina
- The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Department of CardiologyQilu Hospital of Shandong UniversityJinanChina
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18
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Lindström MS, Jurada D, Bursac S, Orsolic I, Bartek J, Volarevic S. Nucleolus as an emerging hub in maintenance of genome stability and cancer pathogenesis. Oncogene 2018; 37:2351-2366. [PMID: 29429989 PMCID: PMC5931986 DOI: 10.1038/s41388-017-0121-z] [Citation(s) in RCA: 146] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2017] [Revised: 11/15/2017] [Accepted: 11/15/2017] [Indexed: 12/13/2022]
Abstract
The nucleolus is the major site for synthesis of ribosomes, complex molecular machines that are responsible for protein synthesis. A wealth of research over the past 20 years has clearly indicated that both quantitative and qualitative alterations in ribosome biogenesis can drive the malignant phenotype via dysregulation of protein synthesis. However, numerous recent proteomic, genomic, and functional studies have implicated the nucleolus in the regulation of processes that are unrelated to ribosome biogenesis, including DNA-damage response, maintenance of genome stability and its spatial organization, epigenetic regulation, cell-cycle control, stress responses, senescence, global gene expression, as well as assembly or maturation of various ribonucleoprotein particles. In this review, the focus will be on features of rDNA genes, which make them highly vulnerable to DNA damage and intra- and interchromosomal recombination as well as built-in mechanisms that prevent and repair rDNA damage, and how dysregulation of this interplay affects genome-wide DNA stability, gene expression and the balance between euchromatin and heterochromatin. We will also present the most recent insights into how malfunction of these cellular processes may be a central driving force of human malignancies, and propose a promising new therapeutic approach for the treatment of cancer.
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Affiliation(s)
- Mikael S Lindström
- Division of Genome Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
| | - Deana Jurada
- Department of Molecular Medicine and Biotechnology, School of Medicine, University of Rijeka, Rijeka, Croatia
- Scientific Center of Excellence for Reproductive and Regenerative Medicine, University of Rijeka, Rijeka, Croatia
| | - Sladana Bursac
- Department of Molecular Medicine and Biotechnology, School of Medicine, University of Rijeka, Rijeka, Croatia
- Scientific Center of Excellence for Reproductive and Regenerative Medicine, University of Rijeka, Rijeka, Croatia
| | - Ines Orsolic
- Department of Molecular Medicine and Biotechnology, School of Medicine, University of Rijeka, Rijeka, Croatia
- Scientific Center of Excellence for Reproductive and Regenerative Medicine, University of Rijeka, Rijeka, Croatia
| | - Jiri Bartek
- Division of Genome Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
- The Danish Cancer Society Research Centre, Copenhagen, Denmark.
| | - Sinisa Volarevic
- Department of Molecular Medicine and Biotechnology, School of Medicine, University of Rijeka, Rijeka, Croatia.
- Scientific Center of Excellence for Reproductive and Regenerative Medicine, University of Rijeka, Rijeka, Croatia.
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19
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The roles of RRP15 in nucleolar formation, ribosome biogenesis and checkpoint control in human cells. Oncotarget 2017; 8:13240-13252. [PMID: 28099941 PMCID: PMC5355092 DOI: 10.18632/oncotarget.14658] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Accepted: 12/27/2016] [Indexed: 01/05/2023] Open
Abstract
The nucleolus controls ribosome biogenesis and its perturbation induces nucleolar stress that inhibits cell cycle progression and activates checkpoint responses. Here, we investigate the roles of ribosomal RNA processing protein, RRP15, in nucleolar formation, ribosome biogenesis, cell cycle progression and checkpoint control in human cells. RRP15 is localized in the nucleolus and required for nucleolar formation. In contrast to the budding yeast Rrp15p that was reported as a component of pre-60S subunits, RRP15 is found in both pre-40S and pre-60S subunits and involved in regulating rRNA transcription and ribosome biogenesis. Perturbation of RRP15 induces nucleolar stress that activates RPL5/RPL11/5S rRNA (RP)-Mdm2-p53 axis checkpoint response and arrests cells at G1-G1/S in p53-proficient non-transformed RPE1 cells but not in p53-deficient HeLa and MCF7 tumor cells. Instead, p53-deficient HeLa and MCF7 cells with RRP15-dependent nucleolar stress enter S-phase with S-phase perturbation that activates ATR-Chk1- γH2AX axis DNA replication/damage checkpoint response, delaying S-G2/M progression and, ultimately, causing cell death. The selective checkpoint response, cell cycle inhibition and/or cytotoxicity induced by RRP15-dependent nucleolar stress in p53-proficient non-transformed cells and p53-deficient tumor cells suggest that RRP15 might be a potential target for cancer therapy.
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20
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Inhibition of Pol I transcription treats murine and human AML by targeting the leukemia-initiating cell population. Blood 2017; 129:2882-2895. [PMID: 28283481 DOI: 10.1182/blood-2016-05-718171] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Accepted: 02/22/2017] [Indexed: 11/20/2022] Open
Abstract
Despite the development of novel drugs, the prospects for many patients with acute myeloid leukemia (AML) remain dismal. This study reveals that the selective inhibitor of RNA polymerase I (Pol I) transcription, CX-5461, effectively treats aggressive AML, including mixed-lineage leukemia-driven AML, and outperforms standard chemotherapies. In addition to the previously characterized mechanism of action of CX-5461 (ie, the induction of p53-dependent apoptotic cell death), the inhibition of Pol I transcription also demonstrates potent efficacy in p53null AML in vivo. This significant survival advantage in both p53WT and p53null leukemic mice treated with CX-5461 is associated with activation of the checkpoint kinases 1/2, an aberrant G2/M cell-cycle progression and induction of myeloid differentiation of the leukemic blasts. The ability to target the leukemic-initiating cell population is thought to be essential for lasting therapeutic benefit. Most strikingly, the acute inhibition of Pol I transcription reduces both the leukemic granulocyte-macrophage progenitor and leukemia-initiating cell (LIC) populations, and suppresses their clonogenic capacity. This suggests that dysregulated Pol I transcription is essential for the maintenance of their leukemia-initiating potential. Together, these findings demonstrate the therapeutic utility of this new class of inhibitors to treat highly aggressive AML by targeting LICs.
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21
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Ye Q, Pang S, Zhang W, Guo X, Wang J, Zhang Y, Liu Y, Wu X, Jiang F. Therapeutic Targeting of RNA Polymerase I With the Small-Molecule CX-5461 for Prevention of Arterial Injury-Induced Neointimal Hyperplasia. Arterioscler Thromb Vasc Biol 2017; 37:476-484. [PMID: 28062495 DOI: 10.1161/atvbaha.116.308401] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2016] [Accepted: 12/21/2016] [Indexed: 01/09/2023]
Abstract
OBJECTIVE RNA polymerase I (Pol I)-dependent rRNA synthesis is a determinant factor in ribosome biogenesis and thus cell proliferation. The importance of dysregulated Pol I activity in cardiovascular disease, however, has not been recognized. Here, we tested the hypothesis that specific inhibition of Pol I might prevent arterial injury-induced neointimal hyperplasia. APPROACH AND RESULTS CX-5461 is a novel selective Pol I inhibitor. Using this tool, we demonstrated that local inhibition of Pol I blocked balloon injury-induced neointima formation in rat carotid arteries in vivo. Neointimal development was associated with augmented rDNA transcriptional activity as evidenced by the increased phosphorylation of upstream binding factor-1. The beneficial effect of CX-5461 was mainly mediated by inducing G2/M cell cycle arrest of proliferating smooth muscle cells without obvious apoptosis. CX-5461 did not induce p53 stabilization but increased p53 phosphorylation and acetylation and activated the ataxia telangiectasia mutated/ataxia telangiectasia and Rad3-related (ATR) pathway. Inhibition of ATR, but not of ataxia telangiectasia mutated, abolished the cytostatic effect of CX-5461 and p53 phosphorylation. In addition, inhibition of p53 or knockdown of the p53 target GADD45 mimicked the effect of ATR inhibition. In vivo experiments showed that the levels of phospho-p53 and acetyl-p53, and activity of the ataxia telangiectasia mutated/ATR pathway were all augmented in CX-5461-treated vessels. CONCLUSIONS Pol I can be therapeutically targeted to inhibit the growth of neointima, supporting that Pol I is a novel biological target for preventing arterial restenosis. Mechanistically, Pol I inhibition elicited G2/M cell cycle arrest in smooth muscle cells via activation of the ATR-p53 axis.
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Affiliation(s)
- Qing Ye
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.)
| | - Shu Pang
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.)
| | - Wenjing Zhang
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.)
| | - Xiaotong Guo
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.)
| | - Jianli Wang
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.)
| | - Yongtao Zhang
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.)
| | - Yang Liu
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.)
| | - Xiao Wu
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.)
| | - Fan Jiang
- From the School of Basic Medicine, Shandong University, Jinan, Shandong Province, China (Q.Y., S.P., W.Z., X.G., J.W., Y.L., F.J.); Key Laboratory of Cardiovascular Remodeling and Function Research & The State and Shandong Province Joint Key Laboratory of Translational Cardiovascular Medicine, Qilu Hospital of Shandong University, Jinan, Shandong, China (X.W.); and Department of Cardiology, Qing Dao Central Hospital, Qing Dao, Shandong Province, China (Y.Z.).
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Transient rRNA synthesis inhibition with CX-5461 is sufficient to elicit growth arrest and cell death in acute lymphoblastic leukemia cells. Oncotarget 2016; 6:34846-58. [PMID: 26472108 PMCID: PMC4741494 DOI: 10.18632/oncotarget.5413] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 09/30/2015] [Indexed: 11/25/2022] Open
Abstract
Enhanced rRNA synthesis is a downstream effect of many of the signaling pathways that are aberrantly activated in cancer, such as the PI3K/mTOR and MAP kinase pathways. Recently, two new rRNA synthesis inhibitors have demonstrated therapeutic effects on cancer cells while sparing normal cells. One of them, CX-5461, is currently in phase 1 clinical trials for hematological malignancies. Here, we investigate the effectiveness of transient treatment with this drug on acute lymphoblastic leukemia cells. Our results show that short exposure to CX-5461 followed by drug washout is sufficient to induce persistent G2 cell-cycle arrest and irreversible commitment to cell death, in spite of rRNA synthesis returning to normal within 24 hours of drug washout. The magnitude of cell death after transient exposure is similar to continuous exposure, but the time to cell death is relatively delayed with transient exposure. In this report, we also investigate rational drug combinations that can potentiate the effect of continuous CX-5461 treatment. We show that the checkpoint abrogator UCN-01 can relieve CX-5461-induced G2 arrest and potentiate the cytotoxic effects of CX-5461. Finally, we show that ERK1/2 is activated upon CX-5461 treatment, and that pharmacological inhibition of MEK1/2 leads to enhanced cell death in combination with CX-5461. In summary, our results provide evidence for the effectiveness of CX-5461 pulse treatment, which may minimize drug related toxicity, and evidence for enhanced effectiveness of CX-5461 in combination with other targeted agents.
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23
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Danilova N, Gazda HT. Ribosomopathies: how a common root can cause a tree of pathologies. Dis Model Mech 2016; 8:1013-26. [PMID: 26398160 PMCID: PMC4582105 DOI: 10.1242/dmm.020529] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Defects in ribosome biogenesis are associated with a group of diseases called the ribosomopathies, of which Diamond-Blackfan anemia (DBA) is the most studied. Ribosomes are composed of ribosomal proteins (RPs) and ribosomal RNA (rRNA). RPs and multiple other factors are necessary for the processing of pre-rRNA, the assembly of ribosomal subunits, their export to the cytoplasm and for the final assembly of subunits into a ribosome. Haploinsufficiency of certain RPs causes DBA, whereas mutations in other factors cause various other ribosomopathies. Despite the general nature of their underlying defects, the clinical manifestations of ribosomopathies differ. In DBA, for example, red blood cell pathology is especially evident. In addition, individuals with DBA often have malformations of limbs, the face and various organs, and also have an increased risk of cancer. Common features shared among human DBA and animal models have emerged, such as small body size, eye defects, duplication or overgrowth of ectoderm-derived structures, and hematopoietic defects. Phenotypes of ribosomopathies are mediated both by p53-dependent and -independent pathways. The current challenge is to identify differences in response to ribosomal stress that lead to specific tissue defects in various ribosomopathies. Here, we review recent findings in this field, with a particular focus on animal models, and discuss how, in some cases, the different phenotypes of ribosomopathies might arise from differences in the spatiotemporal expression of the affected genes. Summary: This paper reviews recent data on Diamond Blackfan anemia and discusses them in connection with other ribosomopathies.
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Affiliation(s)
- Nadia Danilova
- Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095, USA
| | - Hanna T Gazda
- Division of Genetics and Genomics, The Manton Center for Orphan Disease Research, Boston Children's Hospital, Boston, MA 02115, USA Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA Broad Institute, Cambridge, MA 02142, USA
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24
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Gizak A, Grenda M, Mamczur P, Wisniewski J, Sucharski F, Silberring J, McCubrey JA, Wisniewski JR, Rakus D. Insulin/IGF1-PI3K-dependent nucleolar localization of a glycolytic enzyme--phosphoglycerate mutase 2, is necessary for proper structure of nucleolus and RNA synthesis. Oncotarget 2016; 6:17237-50. [PMID: 26033454 PMCID: PMC4627304 DOI: 10.18632/oncotarget.4044] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2015] [Accepted: 04/30/2015] [Indexed: 12/31/2022] Open
Abstract
Phosphoglycerate mutase (PGAM), a conserved, glycolytic enzyme has been found in nucleoli of cancer cells. Here, we present evidence that accumulation of PGAM in the nucleolus is a universal phenomenon concerning not only neoplastically transformed but also non-malignant cells. Nucleolar localization of the enzyme is dependent on the presence of the PGAM2 (muscle) subunit and is regulated by insulin/IGF-1–PI3K signaling pathway as well as drugs influencing ribosomal biogenesis. We document that PGAM interacts with several 40S and 60S ribosomal proteins and that silencing of PGAM2 expression results in disturbance of nucleolar structure, inhibition of RNA synthesis and decrease of the mitotic index of squamous cell carcinoma cells. We conclude that presence of PGAM in the nucleolus is a prerequisite for synthesis and initial assembly of new pre-ribosome subunits.
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Affiliation(s)
- Agnieszka Gizak
- Department of Animal Molecular Physiology, Wroclaw University, Cybulskiego, Wroclaw, Poland
| | - Marcin Grenda
- Department of Animal Molecular Physiology, Wroclaw University, Cybulskiego, Wroclaw, Poland
| | - Piotr Mamczur
- Department of Animal Molecular Physiology, Wroclaw University, Cybulskiego, Wroclaw, Poland
| | - Janusz Wisniewski
- Department of Animal Molecular Physiology, Wroclaw University, Cybulskiego, Wroclaw, Poland
| | - Filip Sucharski
- Department of Biochemistry and Neurobiology, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Kraków, Poland
| | - Jerzy Silberring
- Department of Biochemistry and Neurobiology, Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Kraków, Poland
| | - James A McCubrey
- Department of Microbiology and Immunology, Brody School of Medicine at East Carolina University, Greenville, NC, USA
| | - Jacek R Wisniewski
- Biochemical Proteomics Group, Department of Proteomics and Signal Transduction, Max-Planck-Institute of Biochemistry, Martinsried, Germany
| | - Dariusz Rakus
- Department of Animal Molecular Physiology, Wroclaw University, Cybulskiego, Wroclaw, Poland
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25
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Abstract
ATR (Ataxia Telangiectasia and Rad3-related) is a member of the Phosphatidylinositol 3-kinase-related kinases (PIKKs) family, amongst six other vertebrate proteins known so far. ATR is indispensable for cell survival and its essential role is in sensing DNA damage and initiating appropriate repair responses. In this review we highlight emerging and recent observations connecting ATR to alternative roles in controlling the nuclear envelope, nucleolus, centrosome and other organelles in response to both internal and external stress conditions. We propose that ATR functions control cell plasticity by sensing structural deformations of different cellular components, including DNA and initiating appropriate repair responses, most of which are yet to be understood completely.
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Affiliation(s)
- Gururaj Rao Kidiyoor
- Istituto FIRC di Oncologia Molecolare, Milan, Italy; University of Milan, Milan, Italy
| | - Amit Kumar
- Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group, CSIR-Indian Institute of Toxicology Research, M.G. Marg, Lucknow 226001, India; Academy of Scientific and Innovative Research (AcSIR), India
| | - Marco Foiani
- Istituto FIRC di Oncologia Molecolare, Milan, Italy; University of Milan, Milan, Italy.
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26
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Pirlot C, Thiry M, Trussart C, Di Valentin E, Piette J, Habraken Y. Melanoma antigen-D2: A nucleolar protein undergoing delocalization during cell cycle and after cellular stress. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2016; 1863:581-95. [DOI: 10.1016/j.bbamcr.2015.12.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Revised: 12/11/2015] [Accepted: 12/15/2015] [Indexed: 12/25/2022]
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27
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Goudarzi KM, Lindström MS. Role of ribosomal protein mutations in tumor development (Review). Int J Oncol 2016; 48:1313-24. [PMID: 26892688 PMCID: PMC4777597 DOI: 10.3892/ijo.2016.3387] [Citation(s) in RCA: 122] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2015] [Accepted: 01/07/2016] [Indexed: 12/16/2022] Open
Abstract
Ribosomes are cellular machines essential for protein synthesis. The biogenesis of ribosomes is a highly complex and energy consuming process that initiates in the nucleolus. Recently, a series of studies applying whole-exome or whole-genome sequencing techniques have led to the discovery of ribosomal protein gene mutations in different cancer types. Mutations in ribosomal protein genes have for example been found in endometrial cancer (RPL22), T-cell acute lymphoblastic leukemia (RPL10, RPL5 and RPL11), chronic lymphocytic leukemia (RPS15), colorectal cancer (RPS20), and glioma (RPL5). Moreover, patients suffering from Diamond-Blackfan anemia, a bone marrow failure syndrome caused by mutant ribosomal proteins are also at higher risk for developing leukemia, or solid tumors. Different experimental models indicate potential mechanisms whereby ribosomal proteins may initiate cancer development. In particular, deregulation of the p53 tumor suppressor network and altered mRNA translation are mechanisms likely to be involved. We envisage that changes in expression and the occurrence of ribosomal protein gene mutations play important roles in cancer development. Ribosome biology constitutes a re-emerging vital area of basic and translational cancer research.
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Affiliation(s)
- Kaveh M Goudarzi
- Department of Oncology-Pathology, Karolinska Institutet, Cancer Center Karolinska, CCK R8:05, Karolinska University Hospital in Solna, Stockholm, Sweden
| | - Mikael S Lindström
- Science for Life Laboratory, Division of Translational Medicine and Chemical Biology, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden
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28
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Abstract
Pederson’s career has revolved around the nucleus, nucleolus, and the nucleoproteins that inhabit them.
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29
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Tsimokha AS, Kulichkova VA, Karpova EV, Zaykova JJ, Aksenov ND, Vasilishina AA, Kropotov AV, Antonov A, Barlev NA. DNA damage modulates interactions between microRNAs and the 26S proteasome. Oncotarget 2015; 5:3555-67. [PMID: 25004448 PMCID: PMC4116502 DOI: 10.18632/oncotarget.1957] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
26S proteasomes are known as major non-lysosomal cellular machines for coordinated and specific destruction of ubiquitinylated proteins. The proteolytic activities of proteasomes are controlled by various post-translational modifications in response to environmental cues, including DNA damage. Besides proteolysis, proteasomes also associate with RNA hydrolysis and splicing. Here, we extend the functional diversity of proteasomes by showing that they also dynamically associate with microRNAs (miRNAs) both in the nucleus and cytoplasm of cells. Moreover, DNA damage induced by an anti-cancer drug, doxorubicin, alters the repertoire of proteasome-associated miRNAs, enriching the population of miRNAs that target cell cycle checkpoint regulators and DNA repair proteins. Collectively, these data uncover yet another potential mode of action for proteasomes in the cell via their dynamic association with microRNAs.
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Affiliation(s)
- Anna S Tsimokha
- Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia
| | | | | | | | | | | | | | | | - Nikolai A Barlev
- Institute of Cytology, Russian Academy of Sciences, 194064 St. Petersburg, Russia; Department of Biochemistry, University of Leicester, Leicester, LE1 9HN; Molecular Pharmacology laboratory, Saint-Petersburg Institute of Technology, Saint-Petersburg 190013, Russia
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30
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Harrison SJ, George A, Hannan R. A new window on cancer therapy? Targeting the nucleolus and ribosome biogenesis using the small molecule inhibitor of polymerase I transcription, CX-5461. Int J Hematol Oncol 2015. [DOI: 10.2217/ijh.15.9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Affiliation(s)
- Simon J Harrison
- Department of Haematology, Peter MacCallum Cancer Centre, East Melbourne, Australia
- Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Australia
| | - Amee George
- Department of Cancer Biology & Therapeutics, John Curtin School of Medical Research, ANU College of Medicine, Biology & The Environment, Canberra, Australia
- Department of Pathology, The University of Melbourne, Parkville, Australia
- School of Biomedical Sciences, University of Queensland, St Lucia, Australia
| | - Ross Hannan
- Department of Cancer Biology & Therapeutics, John Curtin School of Medical Research, ANU College of Medicine, Biology & The Environment, Canberra, Australia
- Research Division, Peter MacCallum Cancer Centre, East Melbourne, Australia
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31
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Penzo M, Casoli L, Pollutri D, Sicuro L, Ceccarelli C, Santini D, Taffurelli M, Govoni M, Brina D, Trerè D, Montanaro L. JHDM1B expression regulates ribosome biogenesis and cancer cell growth in a p53 dependent manner. Int J Cancer 2014; 136:E272-81. [DOI: 10.1002/ijc.29240] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Revised: 07/28/2014] [Accepted: 09/17/2014] [Indexed: 01/14/2023]
Affiliation(s)
- Marianna Penzo
- Department of Experimental; Diagnostic and Specialty Medicine, University of Bologna; Italy
| | - Lucia Casoli
- Department of Experimental; Diagnostic and Specialty Medicine, University of Bologna; Italy
| | - Daniela Pollutri
- Department of Experimental; Diagnostic and Specialty Medicine, University of Bologna; Italy
| | - Laura Sicuro
- Department of Experimental; Diagnostic and Specialty Medicine, University of Bologna; Italy
| | - Claudio Ceccarelli
- Department of Experimental; Diagnostic and Specialty Medicine, University of Bologna; Italy
| | - Donatella Santini
- Surgical Pathology Unit; S. Orsola-Malpighi University Hospital; Bologna Italy
| | - Mario Taffurelli
- Department of Medical and Surgical Sciences; University of Bologna; Italy
| | - Marzia Govoni
- Department of Experimental; Diagnostic and Specialty Medicine, University of Bologna; Italy
| | - Daniela Brina
- Laboratory of Molecular Histology and Cell Growth; Division of Oncology; San Raffaele Scientific Institute; Milan Italy
| | - Davide Trerè
- Department of Experimental; Diagnostic and Specialty Medicine, University of Bologna; Italy
| | - Lorenzo Montanaro
- Department of Experimental; Diagnostic and Specialty Medicine, University of Bologna; Italy
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32
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Diesch J, Hannan RD, Sanij E. Perturbations at the ribosomal genes loci are at the centre of cellular dysfunction and human disease. Cell Biosci 2014; 4:43. [PMID: 25949792 PMCID: PMC4422213 DOI: 10.1186/2045-3701-4-43] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 07/27/2014] [Indexed: 01/05/2023] Open
Abstract
Ribosomal RNA (rRNA) gene (rDNA) transcription by RNA Polymerase I (Pol I) drives cell growth and underlies nucleolar structure and function, indirectly coordinating many fundamental cellular processes. The importance of keeping rDNA transcription under tight control is reflected by the fact that deranged Pol I transcription is a feature of cancer and other human disorders. In this review, we discuss multiple aspects of rDNA function including the relationship between Pol I transcription and proliferative capacity, the role of Pol I transcription in mediating nucleolar structure and integrity, and rDNA/nucleolar interactions with the genome and their influence on heterochromatin and global genome stability. Furthermore, we discuss how perturbations in the structure of the rDNA loci might contribute to human disease, in some cases independent of effects on ribosome biogenesis.
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Affiliation(s)
- Jeannine Diesch
- Growth Control Laboratory, Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria 3002, Australia ; Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Ross D Hannan
- Growth Control Laboratory, Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria 3002, Australia ; Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria 3010, Australia ; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia ; Department of Biochemistry and Molecular Biology, University of Melbourne, Parkville, Victoria 3010, Australia ; Division of Cancer Medicine, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria 3002, Australia ; School of Biomedical Sciences, University of Queensland, Brisbane, Queensland 4072, Australia
| | - Elaine Sanij
- Growth Control Laboratory, Research Division, Peter MacCallum Cancer Centre, St. Andrews Place, East Melbourne, Victoria 3002, Australia ; Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, Victoria 3010, Australia ; Department of Pathology, University of Melbourne, Parkville, Victoria 3010, Australia
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33
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Ando M, Yoshikawa K, Iwase Y, Ishiura S. Usefulness of monitoring γ-H2AX and cell cycle arrest in HepG2 cells for estimating genotoxicity using a high-content analysis system. ACTA ACUST UNITED AC 2014; 19:1246-54. [PMID: 24980598 DOI: 10.1177/1087057114541147] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Formation of the phosphorylated protein γ-H2AX is a well-established marker of DNA strand breakage induced by DNA-damaging compounds. Many of these genotoxic compounds also inhibit cell division, leading to arrest at specific points in the cell cycle. Detection of γ-H2AX in combination with cell cycle arrest may therefore be useful for estimating the genotoxicity of experimental compounds. In this study, we examined γ-H2AX formation and cell cycle arrest using high-content screening (HCS) as a method for determining genotoxicity. HepG2 cells were treated with a panel of compounds and then stained with Hoechst 33342 and anti-γ-H2AX, anti-phospho-histone H3, and anti-tubulin antibodies. In total, 19 genotoxic and 7 nongenotoxic compounds were tested in this study. γ-H2AX production was observed within 1 h posttreatment for the majority of Ames-positive compounds, topoisomerase inhibitors, and DNA polymerase inhibitors. Cell cycle arrest in either the S or G2 phase was detected for all DNA-damaging compounds 24 h posttreatment, whereas tubulin-targeting compounds were shown to induce cell cycle arrest in the mitotic phase. Together, these results show that HCS is a simple, rapid, and effective tool for estimating the genotoxicity of compounds through detection of γ-H2AX production and cell cycle arrest.
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Affiliation(s)
- Masamitsu Ando
- Safety Research Laboratories, Mitsubishi Tanabe Pharma Corporation, Chiba, Japan Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
| | - Keisuke Yoshikawa
- Safety Research Laboratories, Mitsubishi Tanabe Pharma Corporation, Chiba, Japan
| | - Yumiko Iwase
- Safety Research Laboratories, Mitsubishi Tanabe Pharma Corporation, Chiba, Japan
| | - Shoichi Ishiura
- Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Tokyo, Japan
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34
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Danilova N, Bibikova E, Covey TM, Nathanson D, Dimitrova E, Konto Y, Lindgren A, Glader B, Radu CG, Sakamoto KM, Lin S. The role of the DNA damage response in zebrafish and cellular models of Diamond Blackfan anemia. Dis Model Mech 2014; 7:895-905. [PMID: 24812435 PMCID: PMC4073278 DOI: 10.1242/dmm.015495] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Ribosomal biogenesis involves the processing of pre-ribosomal RNA. A deficiency of some ribosomal proteins (RPs) impairs processing and causes Diamond Blackfan anemia (DBA), which is associated with anemia, congenital malformations and cancer. p53 mediates many features of DBA, but the mechanism of p53 activation remains unclear. Another hallmark of DBA is the upregulation of adenosine deaminase (ADA), indicating changes in nucleotide metabolism. In RP-deficient zebrafish, we found activation of both nucleotide catabolism and biosynthesis, which is consistent with the need to break and replace the faulty ribosomal RNA. We also found upregulation of deoxynucleotide triphosphate (dNTP) synthesis - a typical response to replication stress and DNA damage. Both RP-deficient zebrafish and human hematopoietic cells showed activation of the ATR/ATM-CHK1/CHK2/p53 pathway. Other features of RP deficiency included an imbalanced dNTP pool, ATP depletion and AMPK activation. Replication stress and DNA damage in cultured cells in non-DBA models can be decreased by exogenous nucleosides. Therefore, we treated RP-deficient zebrafish embryos with exogenous nucleosides and observed decreased activation of p53 and AMPK, reduced apoptosis, and rescue of hematopoiesis. Our data suggest that the DNA damage response contributes to p53 activation in cellular and zebrafish models of DBA. Furthermore, the rescue of RP-deficient zebrafish with exogenous nucleosides suggests that nucleoside supplements could be beneficial in the treatment of DBA.
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Affiliation(s)
- Nadia Danilova
- Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095, USA.
| | - Elena Bibikova
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94305-5208, USA
| | - Todd M Covey
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94305-5208, USA
| | - David Nathanson
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA 90095, USA
| | - Elizabeth Dimitrova
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA 90095, USA
| | - Yoan Konto
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94305-5208, USA
| | - Anne Lindgren
- Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095, USA
| | - Bertil Glader
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94305-5208, USA
| | - Caius G Radu
- Department of Molecular and Medical Pharmacology, University of California, Los Angeles, CA 90095, USA
| | - Kathleen M Sakamoto
- Department of Pediatrics, Stanford University School of Medicine, Stanford, CA 94305-5208, USA
| | - Shuo Lin
- Department of Molecular, Cell & Developmental Biology, University of California, Los Angeles, CA 90095, USA.
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35
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Abstract
Long known as the center of ribosome synthesis, the nucleolus is connected to cell cycle regulation in more subtle ways. One is a surveillance system that reacts promptly when rRNA synthesis or processing is impaired, halting cell cycle progression. Conversely, the nucleolus also acts as a first-responder to growth-related stress signals. Here we review emerging concepts on how these "infraribosomal" links between the nucleolus and cell cycle progression operate in both forward and reverse gears. We offer perspectives on how new cancer therapeutic designs that target this infraribosomal mode of cell growth control may shape future clinical progress.
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Affiliation(s)
- Robert Y L Tsai
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, Texas, USA; and
| | - Thoru Pederson
- Program in Cell and Developmental Dynamics, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, Massachusetts, USA
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36
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Lee CC, Tsai YT, Kao CW, Lee LW, Lai HJ, Ma TH, Chang YS, Yeh NH, Lo SJ. Mutation of a Nopp140 gene dao-5 alters rDNA transcription and increases germ cell apoptosis in C. elegans. Cell Death Dis 2014; 5:e1158. [PMID: 24722283 PMCID: PMC5424100 DOI: 10.1038/cddis.2014.114] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 02/17/2014] [Accepted: 02/20/2014] [Indexed: 01/03/2023]
Abstract
Human diseases of impaired ribosome biogenesis resulting from disruption of rRNA biosynthesis or loss of ribosomal components are collectively described as ‘ribosomopathies'. Treacher Collins syndrome (TCS), a representative human ribosomopathy with craniofacial abnormalities, is attributed to mutations in the tcof1 gene that has a homologous gene called nopp140. Previous studies demonstrated that the dao-5 (dauer and aged animal overexpression gene 5) of Caenorhabditis elegans is a member of nopp140 gene family and plays a role in nucleogenesis in the early embryo. Here, we established a C. elegans model for studying Nopp140-associated ribosomopathy. A null dao-5 mutant ok542 with a semi-infertile phenotype showed a delay in gonadogenesis, as well as a higher incidence of germline apoptosis. These phenotypes in dao-5(ok542) are likely resulted from inefficient rDNA transcription that was observed by run-on analyses and chromatin immunoprecipitation (ChIP) assays measuring the RNA Pol I occupancy on the rDNA promoter. ChIP assays further showed that the modifications of acetylated histone 4 (H4Ac) and dimethylation at the lysine 9 of histone 3 (H3K9me2) around the rDNA promoter were altered in dao-5 mutants compared with the N2 wild type. In addition, activated CEP-1 (a C. elegans p53 homolog) activity was also linked to the loss of DAO-5 in terms of the transcriptional upregulation of two CEP-1 downstream effectors, EGL-1 and CED-13. We propose that the dao-5 mutant of C. elegans can be a valuable model for studying human Nopp140-associated ribosomopathy at the cellular and molecular levels.
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Affiliation(s)
- C-C Lee
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei 112, Taiwan
| | - Y-T Tsai
- 1] Department and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan [2] Molecular Medicine Research Center, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - C-W Kao
- Department and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - L-W Lee
- Department and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - H-J Lai
- Department and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - T-H Ma
- 1] Department and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan [2] Molecular Medicine Research Center, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - Y-S Chang
- 1] Department and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan [2] Molecular Medicine Research Center, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
| | - N-H Yeh
- Institute of Microbiology and Immunology, National Yang-Ming University, Taipei 112, Taiwan
| | - S J Lo
- 1] Institute of Microbiology and Immunology, National Yang-Ming University, Taipei 112, Taiwan [2] Department and Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Taoyuan 333, Taiwan
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37
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Lin T, Meng L, Lin TC, Wu LJ, Pederson T, Tsai RYL. Nucleostemin and GNL3L exercise distinct functions in genome protection and ribosome synthesis, respectively. J Cell Sci 2014; 127:2302-12. [PMID: 24610951 DOI: 10.1242/jcs.143842] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The mammalian nucleolar proteins nucleostemin and GNL3-like (GNL3L) are encoded by paralogous genes that arose from an ancestral invertebrate gene, GNL3. Invertebrate GNL3 has been implicated in ribosome biosynthesis, as has its mammalian descendent, GNL3L. The paralogous mammalian nucleostemin protein has, instead, been implicated in cell renewal. Here, we found that depletion of nucleostemin in a human breast carcinoma cell line triggers prompt and significant DNA damage in S-phase cells without perturbing the initial step of ribosomal (r)RNA synthesis and only mildly affects the total ribosome production. By contrast, GNL3L depletion markedly impairs ribosome production without inducing appreciable DNA damage. These results indicate that, during vertebrate evolution, GNL3L retained the role of the ancestral gene in ribosome biosynthesis, whereas the paralogous nucleostemin acquired a novel genome-protective function. Our results provide a coherent explanation for what had seemed to be contradictory findings about the functions of the invertebrate versus vertebrate genes and are suggestive of how the nucleolus was fine-tuned for a role in genome protection and cell-cycle control as the vertebrates evolved.
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Affiliation(s)
- Tao Lin
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Lingjun Meng
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Tsung-Chin Lin
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Laura J Wu
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
| | - Thoru Pederson
- Program in Cell and Developmental Dynamics, Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, Worcester, MA 01605, USA
| | - Robert Y L Tsai
- Center for Cancer and Stem Cell Biology, Institute of Biosciences and Technology, Texas A&M Health Science Center, Houston, TX 77030, USA
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38
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Quin JE, Devlin JR, Cameron D, Hannan KM, Pearson RB, Hannan RD. Targeting the nucleolus for cancer intervention. Biochim Biophys Acta Mol Basis Dis 2014; 1842:802-16. [PMID: 24389329 DOI: 10.1016/j.bbadis.2013.12.009] [Citation(s) in RCA: 170] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Accepted: 12/17/2013] [Indexed: 12/17/2022]
Abstract
The contribution of the nucleolus to cancer is well established with respect to its traditional role in facilitating ribosome biogenesis and proliferative capacity. More contemporary studies however, infer that nucleoli contribute a much broader role in malignant transformation. Specifically, extra-ribosomal functions of the nucleolus position it as a central integrator of cellular proliferation and stress signaling, and are emerging as important mechanisms for modulating how oncogenes and tumor suppressors operate in normal and malignant cells. The dependence of certain tumor cells to co-opt nucleolar processes to maintain their cancer phenotypes has now clearly been demonstrated by the application of small molecule inhibitors of RNA Polymerase I to block ribosomal DNA transcription and disrupt nucleolar function (Bywater et al., 2012 [1]). These drugs, which selectively kill tumor cells in vivo while sparing normal cells, have now progressed to clinical trials. It is likely that we have only just begun to scratch the surface of the potential of the nucleolus as a new target for cancer therapy, with "suppression of nucleolar stress" representing an emerging "hallmark" of cancer. This article is part of a Special Issue entitled: Role of the Nucleolus in Human Disease.
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Affiliation(s)
- Jaclyn E Quin
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Jennifer R Devlin
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Donald Cameron
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia
| | - Kate M Hannan
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia
| | - Richard B Pearson
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Ross D Hannan
- Oncogenic Signalling and Growth Control Program, Peter MacCallum Cancer Centre, East Melbourne, Victoria, Australia; Department of Biochemistry and Molecular Biology, The University of Melbourne, Parkville, Victoria, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, Victoria, Australia; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia; Department of Pathology, The University of Melbourne, Parkville, Victoria, Australia; School of Biomedical Sciences, The University of Queensland, St Lucia, Queensland, Australia.
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Pickard AJ, Bierbach U. The cell's nucleolus: an emerging target for chemotherapeutic intervention. ChemMedChem 2013; 8:1441-9. [PMID: 23881648 PMCID: PMC3893319 DOI: 10.1002/cmdc.201300262] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2013] [Indexed: 01/01/2023]
Abstract
The transient nucleolus plays a central role in the up-regulated synthesis of ribosomal RNA (rRNA) to sustain ribosome biogenesis, a hallmark of aberrant cell growth. This function, in conjunction with its unique pathohistological features in malignant cells and its ability to mediate apoptosis, renders this sub-nuclear structure a potential target for chemotherapeutic agents. In this Minireview, structurally and functionally diverse small molecules are discussed that have been reported to either interact with the nucleolus directly or perturb its function indirectly by acting on its dynamic components. These molecules include all major classes of nucleic-acid-targeted agents, antimetabolites, kinase inhibitors, anti-inflammatory drugs, natural product antibiotics, oligopeptides, as well as nanoparticles. Together, these molecules are invaluable probes of structure and function of the nucleolus. They also provide a unique opportunity to develop novel strategies for more selective and therefore better-tolerated chemotherapeutic intervention. In this regard, inhibition of RNA polymerase-I-mediated rRNA synthesis appears to be a promising mechanism for killing cancer cells. The recent development of molecules targeted at G-quadruplex-forming rRNA gene sequences, which are currently undergoing clinical trials, seems to attest to the success of this approach.
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Affiliation(s)
- Amanda J. Pickard
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109 (USA)
| | - Ulrich Bierbach
- Department of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109 (USA)
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Hein N, Hannan KM, George AJ, Sanij E, Hannan RD. The nucleolus: an emerging target for cancer therapy. Trends Mol Med 2013; 19:643-54. [PMID: 23953479 DOI: 10.1016/j.molmed.2013.07.005] [Citation(s) in RCA: 181] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 07/10/2013] [Accepted: 07/15/2013] [Indexed: 02/07/2023]
Abstract
For over 100 years, pathologists have utilised an increase in size and number of nucleoli, the subnuclear site of ribosome synthesis, as a marker of aggressive tumours. Despite this, the contribution of the nucleolus and ribosomal RNA synthesis to cancer has been largely overlooked. This concept has recently changed with the demonstration that the nucleolus indirectly controls numerous other cellular functions, in particular, the cellular activity of the critical tumour suppressor protein, p53. Moreover, selective inhibition of ribosomal gene transcription in the nucleolus has been shown to be an effective therapeutic strategy to promote cancer-specific activation of p53. This article reviews the largely untapped potential of the nucleolus and ribosomal gene transcription as exciting new targets for cancer therapy.
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Affiliation(s)
- Nadine Hein
- Division of Cancer Research, Peter MacCallum Cancer Centre, East Melbourne, 3002, Victoria, Australia; Sir Peter MacCallum Department of Oncology, The University of Melbourne, Parkville, 3010, Victoria, Australia
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