101
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Richard MA, Lupo PJ, Morton LM, Yasui YA, Sapkota YA, Arnold MA, Aubert G, Neglia JP, Turcotte LM, Leisenring WM, Sampson JN, Chanock SJ, Hudson MM, Armstrong GT, Robison LL, Bhatia S, Gramatges MM. Genetic variation in POT1 and risk of thyroid subsequent malignant neoplasm: A report from the Childhood Cancer Survivor Study. PLoS One 2020; 15:e0228887. [PMID: 32040538 PMCID: PMC7010302 DOI: 10.1371/journal.pone.0228887] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Accepted: 01/24/2020] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Telomere length is associated with risk for thyroid subsequent malignant neoplasm in survivors of childhood cancer. Here, we investigated associations between thyroid subsequent malignant neoplasm and inherited variation in telomere maintenance genes. METHODS We used RegulomeDB to annotate the functional impact of variants mapping to 14 telomere maintenance genes among 5,066 five-or-more year survivors who participate in the Childhood Cancer Survivor Study (CCSS) and who are longitudinally followed for incidence of subsequent cancers. Hazard ratios for thyroid subsequent malignant neoplasm were calculated for 60 putatively functional variants with minor allele frequency ≥1% in or near telomere maintenance genes. Functional impact was further assessed by measuring telomere length in leukocyte subsets. RESULTS The minor allele at Protection of Telomeres-1 (POT1) rs58722976 was associated with increased risk for thyroid subsequent malignant neoplasm (adjusted HR = 6.1, 95% CI: 2.4, 15.5, P = 0.0001; Fisher's exact P = 0.001). This imputed SNP was present in three out of 110 survivors who developed thyroid cancer vs. 14 out of 4,956 survivors who did not develop thyroid cancer. In a subset of 83 survivors with leukocyte telomere length data available, this variant was associated with longer telomeres in B lymphocytes (P = 0.004). CONCLUSIONS Using a functional variant approach, we identified and confirmed an association between a low frequency intronic regulatory POT1 variant and thyroid subsequent malignant neoplasm in survivors of childhood cancer. These results suggest that intronic variation in POT1 may affect key protein binding interactions that impact telomere maintenance and genomic integrity.
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Affiliation(s)
- Melissa A. Richard
- Department of Pediatrics, Baylor College of Medicine and Dan L. Duncan Cancer Center, Houston, TX, United States of America
| | - Philip J. Lupo
- Department of Pediatrics, Baylor College of Medicine and Dan L. Duncan Cancer Center, Houston, TX, United States of America
| | - Lindsay M. Morton
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, United States of America
| | - Yutaka A. Yasui
- Department of Epidemiology and Cancer Control, St. Jude Children’s Research Hospital, Memphis, TN, United States of America
| | - Yadav A. Sapkota
- Department of Epidemiology and Cancer Control, St. Jude Children’s Research Hospital, Memphis, TN, United States of America
| | - Michael A. Arnold
- Department of Pathology and Laboratory Medicine, Nationwide Children’s Hospital, Columbus, Ohio, United States of America
| | - Geraldine Aubert
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, BC, Canada
| | - Joseph P. Neglia
- Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States of America
| | - Lucie M. Turcotte
- Department of Pediatrics, University of Minnesota, Minneapolis, MN, United States of America
| | - Wendy M. Leisenring
- Division of Clinical Research, Fred Hutchinson Cancer Research Center, Seattle, WA, United States of America
| | - Joshua N. Sampson
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, United States of America
| | - Stephen J. Chanock
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, MD, United States of America
- Cancer Genomics Research Laboratory, Leidos Biomedical Research, Inc., Frederick National Laboratory for Cancer Research, Frederick, Maryland, United States of America
| | - Melissa M. Hudson
- Department of Oncology, St. Jude Children’s Research Hospital, Memphis, TN, United States of America
| | - Gregory T. Armstrong
- Department of Epidemiology and Cancer Control, St. Jude Children’s Research Hospital, Memphis, TN, United States of America
| | - Leslie L. Robison
- Department of Epidemiology and Cancer Control, St. Jude Children’s Research Hospital, Memphis, TN, United States of America
| | - Smita Bhatia
- Institute for Cancer Outcomes and Survivorship, University of Alabama at Birmingham, Birmingham, AL, England
| | - Maria Monica Gramatges
- Department of Pediatrics, Baylor College of Medicine and Dan L. Duncan Cancer Center, Houston, TX, United States of America
- * E-mail:
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102
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Abstract
RNA plays essential roles in not only translating nucleic acids into proteins, but also in gene regulation, environmental interactions and many human diseases. Nature uses over 150 chemical modifications to decorate RNA and diversify its functions. With the fast-growing RNA research in the burgeoning field of 'epitranscriptome', a term describes post-transcriptional RNA modifications that can dynamically change the transcriptome, it becomes clear that these modifications participate in modulating gene expression and controlling the cell fate, thereby igniting the new interests in RNA-based drug discovery. The dynamics of these RNA chemical modifications is orchestrated by coordinated actions of an array of writer, reader and eraser proteins. Deregulated expression of these RNA modifying proteins can lead to many human diseases including cancer. In this review, we highlight several critical modifications, namely m6A, m1A, m5C, inosine and pseudouridine, in both coding and non-coding RNAs. In parallel, we present a few other cancer-related tRNA and rRNA modifications. We further discuss their roles in cancer promotion or tumour suppression. Understanding the molecular mechanisms underlying the biogenesis and turnover of these RNA modifications will be of great significance in the design and development of novel anticancer drugs.
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Affiliation(s)
- Phensinee Haruehanroengra
- Department of Chemistry and the RNA Institute, College of Arts and Science, University at Albany, State University of New York , Albany, NY, USA
| | - Ya Ying Zheng
- Department of Chemistry and the RNA Institute, College of Arts and Science, University at Albany, State University of New York , Albany, NY, USA
| | - Yubin Zhou
- Institute of Biosciences and Technology, Texas A&M University , Houston, TX, USA
| | - Yun Huang
- Institute of Biosciences and Technology, Texas A&M University , Houston, TX, USA
| | - Jia Sheng
- Department of Chemistry and the RNA Institute, College of Arts and Science, University at Albany, State University of New York , Albany, NY, USA
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103
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Smith EM, Pendlebury DF, Nandakumar J. Structural biology of telomeres and telomerase. Cell Mol Life Sci 2020; 77:61-79. [PMID: 31728577 PMCID: PMC6986361 DOI: 10.1007/s00018-019-03369-x] [Citation(s) in RCA: 103] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 10/11/2019] [Accepted: 10/31/2019] [Indexed: 01/16/2023]
Abstract
Telomeres are protein-DNA complexes that protect chromosome ends from illicit ligation and resection. Telomerase is a ribonucleoprotein enzyme that synthesizes telomeric DNA to counter telomere shortening. Human telomeres are composed of complexes between telomeric DNA and a six-protein complex known as shelterin. The shelterin proteins TRF1 and TRF2 provide the binding affinity and specificity for double-stranded telomeric DNA, while the POT1-TPP1 shelterin subcomplex coats the single-stranded telomeric G-rich overhang that is characteristic of all our chromosome ends. By capping chromosome ends, shelterin protects telomeric DNA from unwanted degradation and end-to-end fusion events. Structures of the human shelterin proteins reveal a network of constitutive and context-specific interactions. The shelterin protein-DNA structures reveal the basis for both the high affinity and DNA sequence specificity of these interactions, and explain how shelterin efficiently protects chromosome ends from genome instability. Several protein-protein interactions, many provided by the shelterin component TIN2, are critical for upholding the end-protection function of shelterin. A survey of these protein-protein interfaces within shelterin reveals a series of "domain-peptide" interactions that allow for efficient binding and adaptability towards new functions. While the modular nature of shelterin has facilitated its part-by-part structural characterization, the interdependence of subunits within telomerase has made its structural solution more challenging. However, the exploitation of several homologs in combination with recent advancements in cryo-EM capabilities has led to an exponential increase in our knowledge of the structural biology underlying telomerase function. Telomerase homologs from a wide range of eukaryotes show a typical retroviral reverse transcriptase-like protein core reinforced with elements that deliver telomerase-specific functions including recruitment to telomeres and high telomere-repeat addition processivity. In addition to providing the template for reverse transcription, the RNA component of telomerase provides a scaffold for the catalytic and accessory protein subunits, defines the limits of the telomeric repeat sequence, and plays a critical role in RNP assembly, stability, and trafficking. While a high-resolution definition of the human telomerase structure is only beginning to emerge, the quick pace of technical progress forecasts imminent breakthroughs in this area. Here, we review the structural biology surrounding telomeres and telomerase to provide a molecular description of mammalian chromosome end protection and end replication.
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Affiliation(s)
- Eric M Smith
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Devon F Pendlebury
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Jayakrishnan Nandakumar
- Department of Molecular, Cellular, and Developmental Biology, University of Michigan, Ann Arbor, MI, 48109, USA.
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI, 48109, USA.
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104
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Xu C, Xie N, Su Y, Sun Z, Liang Y, Zhang N, Liu D, Jia S, Xing X, Han L, Li G, Tong T, Chen J. HnRNP F/H associate with hTERC and telomerase holoenzyme to modulate telomerase function and promote cell proliferation. Cell Death Differ 2019; 27:1998-2013. [PMID: 31863069 PMCID: PMC7244589 DOI: 10.1038/s41418-019-0483-6] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2019] [Revised: 12/09/2019] [Accepted: 12/10/2019] [Indexed: 12/16/2022] Open
Abstract
Human telomerase RNA component hTERC comprises multiple motifs that contribute to hTERC biogenesis, holoenzyme activity, and enzyme recruitment to telomeres. hTERC contains several guanine tracts (G-tracts) at its 5′-end, but its associated proteins and potential roles in telomerase function are still poorly understood. The heterogeneous nuclear ribonucleoproteins F, H1, and H2 (hnRNP F/H) are splicing factors that preferentially bind to poly(G)-rich sequences RNA. Here, we demonstrate that hnRNP F/H associate with both hTERC and telomerase holoenzyme to regulate telomerase activity. We reveal hnRNP F/H bind to the 5′-end region of hTERC in vitro and in vivo, and identify the first three G-tracts of hTERC and qRRM1 domain of hnRNP F/H are required for their interaction. Furthermore, hnRNP F/H also directly interact with telomerase holoenzyme. Functionally, we show that hnRNP F/H plays important roles in modulating telomerase activity and telomere length. Moreover, hnRNP F/H deletion greatly impair cancer and stem cell proliferation, and induce stem cell senescence, while hnRNP F/H overexpression delay stem cell senescence. Collectively, our findings unveil a novel role of hnRNP F/H as the binding partners of hTERC and telomerase holoenzyme to regulate telomerase function.
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Affiliation(s)
- Chenzhong Xu
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Nan Xie
- Department of Physiology and Pathophysiology, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Yuanyuan Su
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Zhaomeng Sun
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Yao Liang
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Na Zhang
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Doudou Liu
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Shuqin Jia
- Department of Molecular Diagnostics, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, 100142, China
| | - Xiaofang Xing
- Department of Molecular Diagnostics, Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education), Peking University Cancer Hospital & Institute, Beijing, 100142, China
| | - Limin Han
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Guodong Li
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Tanjun Tong
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China
| | - Jun Chen
- Peking University Research Center on Aging, Beijing Key Laboratory of Protein Posttranslational Modifications and Cell Function, Department of Biochemistry and Molecular Biology, Department of Integration of Chinese and Western Medicine, School of Basic Medical Science, Peking University, Beijing, 100191, China.
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105
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Wang Y, Sušac L, Feigon J. Structural Biology of Telomerase. Cold Spring Harb Perspect Biol 2019; 11:cshperspect.a032383. [PMID: 31451513 DOI: 10.1101/cshperspect.a032383] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Telomerase is a DNA polymerase that extends the 3' ends of chromosomes by processively synthesizing multiple telomeric repeats. It is a unique ribonucleoprotein (RNP) containing a specialized telomerase reverse transcriptase (TERT) and telomerase RNA (TER) with its own template and other elements required with TERT for activity (catalytic core), as well as species-specific TER-binding proteins important for biogenesis and assembly (core RNP); other proteins bind telomerase transiently or constitutively to allow association of telomerase and other proteins with telomere ends for regulation of DNA synthesis. Here we describe how nuclear magnetic resonance (NMR) spectroscopy and X-ray crystallography of TER and protein domains helped define the structure and function of the core RNP, laying the groundwork for interpreting negative-stain and cryo electron microscopy (cryo-EM) density maps of Tetrahymena thermophila and human telomerase holoenzymes. As the resolution has improved from ∼30 Å to ∼5 Å, these studies have provided increasingly detailed information on telomerase architecture and mechanism.
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Affiliation(s)
- Yaqiang Wang
- Department of Chemistry and Biochemistry, University of California Los Angeles (UCLA), Los Angeles, California 90095-1569
| | - Lukas Sušac
- Department of Chemistry and Biochemistry, University of California Los Angeles (UCLA), Los Angeles, California 90095-1569
| | - Juli Feigon
- Department of Chemistry and Biochemistry, University of California Los Angeles (UCLA), Los Angeles, California 90095-1569
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106
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MacNeil DE, Lambert-Lanteigne P, Autexier C. N-terminal residues of human dyskerin are required for interactions with telomerase RNA that prevent RNA degradation. Nucleic Acids Res 2019; 47:5368-5380. [PMID: 30931479 PMCID: PMC6547437 DOI: 10.1093/nar/gkz233] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/19/2019] [Accepted: 03/25/2019] [Indexed: 12/16/2022] Open
Abstract
The telomerase holoenzyme responsible for maintaining telomeres in vertebrates requires many components in vivo, including dyskerin. Dyskerin binds and regulates the accumulation of the human telomerase RNA, hTR, as well as other non-coding RNAs that share the conserved H/ACA box motif. The precise mechanism by which dyskerin controls hTR levels is unknown, but is evidenced by defective hTR accumulation caused by substitutions in dyskerin, that are observed in the X-linked telomere biology disorder dyskeratosis congenita (X-DC). To understand the role of dyskerin in hTR accumulation, we analyzed X-DC substitutions K39E and K43E in the poorly characterized dyskerin N-terminus, and A353V within the canonical RNA binding domain (the PUA). These variants exhibited impaired binding to hTR and polyadenylated hTR species, while interactions with other H/ACA RNAs appear largely unperturbed by the N-terminal substitutions. hTR accumulation and telomerase activity defects of dyskerin-deficient cells were rescued by wildtype dyskerin but not the variants. hTR 3′ extended or polyadenylated species did not accumulate, suggesting hTR precursor degradation occurs upstream of mature complex assembly in the absence of dyskerin binding. Our findings demonstrate that the dyskerin-hTR interaction mediated by PUA and N-terminal residues of dyskerin is crucial to prevent unchecked hTR degradation.
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Affiliation(s)
- Deanna E MacNeil
- Jewish General Hospital of McGill University, Lady Davis Institute, Montreal, Quebec H3T 1E2, Canada.,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 0C7, Canada
| | - Patrick Lambert-Lanteigne
- Jewish General Hospital of McGill University, Lady Davis Institute, Montreal, Quebec H3T 1E2, Canada
| | - Chantal Autexier
- Jewish General Hospital of McGill University, Lady Davis Institute, Montreal, Quebec H3T 1E2, Canada.,Department of Anatomy and Cell Biology, McGill University, Montreal, Quebec H3A 0C7, Canada
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107
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Yeh JK, Lin MH, Wang CY. Telomeres as Therapeutic Targets in Heart Disease. ACTA ACUST UNITED AC 2019; 4:855-865. [PMID: 31998853 PMCID: PMC6978555 DOI: 10.1016/j.jacbts.2019.05.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Revised: 05/27/2019] [Accepted: 05/28/2019] [Indexed: 12/14/2022]
Abstract
Age-associated CVDs impose a great burden on current health systems. Despite the fact that current strong evidence supports the links among aging, telomere attrition, and CVDs, there is no clear direction for the development of telomere therapeutics against CVDs. This review focuses on immune modulation, CHIP, pharmaceutical interventions, and gene therapy for their therapeutic roles in age-associated CVDs. The future goal of telomere cardiovascular therapy in young subjects is to prevent senescence and diseases, whereas in older adult subjects, the goal is restoration of cardiovascular functions. Further studies on the telomere-CHIP-atherosclerosis axis may shed insights on how to achieve these 2 different therapeutic targets.
Telomeres are double-stranded repeats of G-rich tandem DNA sequences that gradually shorten with each cell division. Aging, inflammation, and oxidative stress accelerate the process of telomere shortening. Telomerase counteracts this process by maintaining and elongating the telomere length. Patients with atherosclerotic diseases and cardiovascular risk factors (e.g., smoking, obesity, sedentary lifestyle, and hypertension) have shorter leukocyte telomere length. Following myocardial infarction, telomerase expression and activity in cardiomyocytes and endothelial cells increase significantly, implying that telomerase plays a role in regulating tissue repairs in heart diseases. Although previous studies have focused on the changes of telomeres in heart diseases and the telomere length as a marker for aging cardiovascular systems, recent studies have explored the potential of telomeres and telomerase in the treatment of cardiovascular diseases. This review discusses the significant advancements of telomere therapeutics in gene therapy, atherosclerosis, anti-inflammation, and immune modulation in patients with cardiovascular diseases.
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Affiliation(s)
- Jih-Kai Yeh
- Department of Cardiology, Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Taoyuan City, Taiwan
| | - Mei-Hsiu Lin
- Department of Cardiology, Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Taoyuan City, Taiwan
| | - Chao-Yung Wang
- Department of Cardiology, Chang Gung Memorial Hospital, and Chang Gung University College of Medicine, Taoyuan City, Taiwan.,Institute of Cellular and System Medicine, National Health Research Institutes, Zhunan, Taiwan
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108
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Ackermann S, Fischer M. Telomere Maintenance in Pediatric Cancer. Int J Mol Sci 2019; 20:E5836. [PMID: 31757062 PMCID: PMC6928840 DOI: 10.3390/ijms20235836] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/15/2019] [Accepted: 11/18/2019] [Indexed: 02/06/2023] Open
Abstract
Telomere length has been proposed as a biomarker of biological age and a risk factor for age-related diseases and cancer. Substantial progress has been made in recent decades in understanding the complex molecular relationships in this research field. However, the majority of telomere studies have been conducted in adults. The data on telomere dynamics in pediatric cancers is limited, and interpretation can be challenging, especially in cases where results are contrasting to those in adult entities. This review describes recent advances in the molecular characterization of structure and function of telomeres, regulation of telomerase activity in cancer pathogenesis in general, and highlights the key advances that have expanded our views on telomere biology in pediatric cancer, with special emphasis on the central role of telomere maintenance in neuroblastoma. Furthermore, open questions in the field of telomere maintenance research are discussed in the context of recently published literature.
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Affiliation(s)
- Sandra Ackermann
- Department of Experimental Pediatric Oncology, University Children’s Hospital of Cologne, Faculty of Medicine and University Hospital of Cologne, Kerpener Straße 62, 50937 Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Robert-Koch-Straße 21, 50931 Cologne, Germany
| | - Matthias Fischer
- Department of Experimental Pediatric Oncology, University Children’s Hospital of Cologne, Faculty of Medicine and University Hospital of Cologne, Kerpener Straße 62, 50937 Cologne, Germany
- Center for Molecular Medicine Cologne (CMMC), University of Cologne, Robert-Koch-Straße 21, 50931 Cologne, Germany
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109
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Recognizing a Non-classical Telomeropathy before Hematopoietic Stem Cell Transplantation in Pediatric Patients: A Case Series. Hemasphere 2019; 3:e282. [PMID: 31723852 PMCID: PMC6745921 DOI: 10.1097/hs9.0000000000000282] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/06/2019] [Accepted: 05/06/2019] [Indexed: 11/26/2022] Open
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110
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Dyskerin Mutations Present in Dyskeratosis Congenita Patients Increase Oxidative Stress and DNA Damage Signalling in Dictyostelium Discoideum. Cells 2019; 8:cells8111406. [PMID: 31717312 PMCID: PMC6912284 DOI: 10.3390/cells8111406] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Revised: 11/04/2019] [Accepted: 11/05/2019] [Indexed: 12/17/2022] Open
Abstract
Dyskerin is a protein involved in the formation of small nucleolar and small Cajal body ribonucleoproteins. These complexes participate in RNA pseudouridylation and are also components of the telomerase complex required for telomere elongation. Dyskerin mutations cause a rare disease, X-linked dyskeratosis congenita, with no curative treatment. The social amoeba Dictyostelium discoideum contains a gene coding for a dyskerin homologous protein. In this article D. discoideum mutant strains that have mutations corresponding to mutations found in dyskeratosis congenita patients are described. The phenotype of the mutant strains has been studied and no alterations were observed in pseudouridylation activity and telomere structure. Mutant strains showed increased proliferation on liquid culture but reduced growth feeding on bacteria. The results obtained indicated the existence of increased DNA damage response and reactive oxygen species, as also reported in human Dyskeratosis congenita cells and some other disease models. These data, together with the haploid character of D. discoideum vegetative cells, that resemble the genomic structure of the human dyskerin gene, located in the X chromosome, support the conclusion that D. discoideum can be a good model system for the study of this disease.
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111
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Niewisch MR, Savage SA. An update on the biology and management of dyskeratosis congenita and related telomere biology disorders. Expert Rev Hematol 2019; 12:1037-1052. [PMID: 31478401 DOI: 10.1080/17474086.2019.1662720] [Citation(s) in RCA: 99] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Introduction: Telomere biology disorders (TBDs) encompass a group of illnesses caused by germline mutations in genes regulating telomere maintenance, resulting in very short telomeres. Possible TBD manifestations range from complex multisystem disorders with onset in childhood such as dyskeratosis congenita (DC), Hoyeraal-Hreidarsson syndrome, Revesz syndrome and Coats plus to adults presenting with one or two DC-related features.Areas covered: The discovery of multiple genetic causes and inheritance patterns has led to the recognition of a spectrum of clinical features affecting multiple organ systems. Patients with DC and associated TBDs are at high risk of bone marrow failure, cancer, liver and pulmonary disease. Recently, vascular diseases, including pulmonary arteriovenous malformations and gastrointestinal telangiectasias, have been recognized as additional manifestations. Diagnostics include detection of very short leukocyte telomeres and germline genetic testing. Hematopoietic cell transplantation and lung transplantation are the only current therapeutic modalities but are complicated by numerous comorbidities. This review summarizes the pathophysiology underlying TBDs, associated clinical features, management recommendations and therapeutic options.Expert opinion: Understanding TBDs as complex, multisystem disorders with a heterogenous genetic background and diverse phenotypes, highlights the importance of clinical surveillance and the urgent need to develop new therapeutic strategies to improve health outcomes.
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Affiliation(s)
- Marena R Niewisch
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
| | - Sharon A Savage
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Bethesda, MD, USA
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112
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Gable DL, Gaysinskaya V, Atik CC, Talbot CC, Kang B, Stanley SE, Pugh EW, Amat-Codina N, Schenk KM, Arcasoy MO, Brayton C, Florea L, Armanios M. ZCCHC8, the nuclear exosome targeting component, is mutated in familial pulmonary fibrosis and is required for telomerase RNA maturation. Genes Dev 2019; 33:1381-1396. [PMID: 31488579 PMCID: PMC6771387 DOI: 10.1101/gad.326785.119] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 08/15/2019] [Indexed: 11/25/2022]
Abstract
In this study, Gable et al. follow a family with early onset pulmonary fibrosis and report the discovery of a new genetic cause of pulmonary fibrosis. They use multidimensional analysis methods, involving molecular studies, mouse model, and transcriptome-wide studies to show that heterozygous loss-of-function of the exosomal targeting protein ZCCHC8 to identify a novel cause of telomerase insufficiency in human disease. Short telomere syndromes manifest as familial idiopathic pulmonary fibrosis; they are the most common premature aging disorders. We used genome-wide linkage to identify heterozygous loss of function of ZCCHC8, a zinc-knuckle containing protein, as a cause of autosomal dominant pulmonary fibrosis. ZCCHC8 associated with TR and was required for telomerase function. In ZCCHC8 knockout cells and in mutation carriers, genomically extended telomerase RNA (TR) accumulated at the expense of mature TR, consistent with a role for ZCCHC8 in mediating TR 3′ end targeting to the nuclear RNA exosome. We generated Zcchc8-null mice and found that heterozygotes, similar to human mutation carriers, had TR insufficiency but an otherwise preserved transcriptome. In contrast, Zcchc8−/− mice developed progressive and fatal neurodevelopmental pathology with features of a ciliopathy. The Zcchc8−/− brain transcriptome was highly dysregulated, showing accumulation and 3′ end misprocessing of other low-abundance RNAs, including those encoding cilia components as well as the intronless replication-dependent histones. Our data identify a novel cause of human short telomere syndromes-familial pulmonary fibrosis and uncover nuclear exosome targeting as an essential 3′ end maturation mechanism that vertebrate TR shares with replication-dependent histones.
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Affiliation(s)
- Dustin L Gable
- Medical Scientist Training Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.,Telomere Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Valeriya Gaysinskaya
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.,Telomere Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Christine C Atik
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.,Telomere Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - C Conover Talbot
- Institute for Basic Biomedical Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Byunghak Kang
- Department of Comparative and Molecular Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Susan E Stanley
- Medical Scientist Training Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA.,Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.,Telomere Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Elizabeth W Pugh
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Nuria Amat-Codina
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.,Telomere Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Kara M Schenk
- Osler Medical Housestaff Training Program, Johns Hopkins University School of Medicine, Baltimore, Maryland 21205, USA
| | - Murat O Arcasoy
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina 27708, USA
| | - Cory Brayton
- Department of Comparative and Molecular Pathobiology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Liliana Florea
- Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
| | - Mary Armanios
- Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.,Telomere Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.,Department of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA.,Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, Maryland 21287, USA
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113
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Deng T, Huang Y, Weng K, Lin S, Li Y, Shi G, Chen Y, Huang J, Liu D, Ma W, Songyang Z. TOE1 acts as a 3' exonuclease for telomerase RNA and regulates telomere maintenance. Nucleic Acids Res 2019; 47:391-405. [PMID: 30371886 PMCID: PMC6326811 DOI: 10.1093/nar/gky1019] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2018] [Accepted: 10/14/2018] [Indexed: 12/14/2022] Open
Abstract
In human cells, telomeres are elongated by the telomerase complex that contains the reverse transcriptase hTERT and RNA template TERC/hTR. Poly(A)-specific ribonuclease (PARN) is known to trim hTR precursors by removing poly(A) tails. However, the precise mechanism of hTR 3′ maturation remains largely unknown. Target of Egr1 (TOE1) is an Asp-Glu-Asp-Asp (DEDD) domain containing deadenylase that is mutated in the human disease Pontocerebella Hypoplasia Type 7 (PCH7) and implicated in snRNA and hTR processing. We have previously found TOE1 to localize specifically in Cajal bodies, where telomerase RNP complex assembly takes place. In this study, we showed that TOE1 could interact with hTR and the telomerase complex. TOE1-deficient cells accumulated hTR precursors, including oligoadenylated and 3′-extended forms, which was accompanied by impaired telomerase activity and shortened telomeres. Telomerase activity in TOE1-deficient cells could be rescued by wild-type TOE1 but not the catalytically inactive mutant. Our results suggest that hTR 3′ end processing likely involves multiple exonucleases that work in parallel and/or sequentially, where TOE1 may function non-redundantly as a 3′-to-5′ exonuclease in conjunction with PARN. Our study highlights a mechanistic link between TOE1 mutation, improper hTR processing and telomere dysfunction in diseases such as PCH7.
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Affiliation(s)
- Tingting Deng
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Yan Huang
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Kai Weng
- Guangzhou Institute of Pediatrics, Guangzhou Women and Children's Medical Centre, Guangzhou 510623, China
| | - Song Lin
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Yujing Li
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Guang Shi
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Yali Chen
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Junjiu Huang
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Dan Liu
- Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
| | - Wenbin Ma
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China
| | - Zhou Songyang
- State Key Laboratory of Oncology in South China, Cancer Center, Collaborative Innovation Center for Cancer Medicine, MOE Key Laboratory of Gene Function and Regulation, School of Life Sciences, Sun Yat-sen University, Guangzhou 510006, China.,Guangzhou Regenerative Medicine and Health-Guangdong Laboratory (GRMH-GDL), Institute of Healthy Aging Research, Sun Yat-sen University, Guangzhou 510006, China.,Verna and Marrs Mclean Department of Biochemistry and Molecular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
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114
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Donaires FS, Alves-Paiva RM, Gutierrez-Rodrigues F, da Silva FB, Tellechea MF, Moreira LF, Santana BA, Traina F, Dunbar CE, Winkler T, Calado RT. Telomere dynamics and hematopoietic differentiation of human DKC1-mutant induced pluripotent stem cells. Stem Cell Res 2019; 40:101540. [PMID: 31479877 DOI: 10.1016/j.scr.2019.101540] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 08/08/2019] [Accepted: 08/19/2019] [Indexed: 02/07/2023] Open
Abstract
Telomeropathies are a group of phenotypically heterogeneous diseases molecularly unified by pathogenic mutations in telomere-maintenance genes causing critically short telomeres. X-linked dyskeratosis congenita (DC), the prototypical telomere disease, manifested with ectodermal dysplasia, cancer predisposition, and severe bone marrow failure, is caused by mutations in DKC1, encoding a protein responsible for telomerase holoenzyme complex stability. To investigate the effects of pathogenic DKC1 mutations on telomere repair and hematopoietic development, we derived induced pluripotent stem cells (iPSCs) from fibroblasts of a DC patient carrying the most frequent mutation: DKC1 p.A353V. Telomeres eroded immediately after reprogramming in DKC1-mutant iPSCs but stabilized in later passages. The telomerase activity of mutant iPSCs was comparable to that observed in human embryonic stem cells, and no evidence of alternative lengthening of telomere pathways was detected. Hematopoietic differentiation was carried out in DKC1-mutant iPSC clones that resulted in increased capacity to generate hematopoietic colony-forming units compared to controls. Our study indicates that telomerase-dependent telomere maintenance is defective in pluripotent stem cells harboring DKC1 mutation and unable to elongate telomeres, but sufficient to maintain cell proliferation and self-renewal, as well as to support the primitive hematopoiesis, the program that is recapitulated with our differentiation protocol.
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Affiliation(s)
- Flavia S Donaires
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Raquel M Alves-Paiva
- Department of Medical Imaging, Hematology, and Clinical Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Fernanda Gutierrez-Rodrigues
- Department of Medical Imaging, Hematology, and Clinical Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Fernanda Borges da Silva
- Department of Medical Imaging, Hematology, and Clinical Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Maria Florencia Tellechea
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Lilian Figueiredo Moreira
- Department of Medical Imaging, Hematology, and Clinical Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Barbara A Santana
- Department of Medical Imaging, Hematology, and Clinical Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Fabiola Traina
- Department of Medical Imaging, Hematology, and Clinical Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil
| | - Cynthia E Dunbar
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Thomas Winkler
- National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | - Rodrigo T Calado
- Department of Medical Imaging, Hematology, and Clinical Oncology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, SP, Brazil.
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115
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Richards LA, Kumari A, Knezevic K, Thoms JA, von Jonquieres G, Napier CE, Ali Z, O'Brien R, Marks-Bluth J, Maritz MF, Pickett HA, Morris J, Pimanda JE, MacKenzie KL. DKC1 is a transcriptional target of GATA1 and drives upregulation of telomerase activity in normal human erythroblasts. Haematologica 2019; 105:1517-1526. [PMID: 31413099 PMCID: PMC7271591 DOI: 10.3324/haematol.2018.215699] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 08/13/2019] [Indexed: 12/15/2022] Open
Abstract
Telomerase is a ribonucleoprotein complex that maintains the length and integrity of telomeres, and thereby enables cellular proliferation. Understanding the regulation of telomerase in hematopoietic cells is relevant to the pathogenesis of leukemia, in which telomerase is constitutively activated, as well as bone marrow failure syndromes that feature telomerase insufficiency. Past studies showing high levels of telomerase in human erythroblasts and a prevalence of anemia in disorders of telomerase insufficiency provide the rationale for investigating telomerase regulation in erythroid cells. Here it is shown for the first time that the telomerase RNA-binding protein dyskerin (encoded by DKC1) is dramatically upregulated as human hematopoietic stem and progenitor cells commit to the erythroid lineage, driving an increase in telomerase activity in the presence of limiting amounts of TERT mRNA. It is also shown that upregulation of DKC1 was necessary for expansion of glycophorin A+ erythroblasts and sufficient to extend telomeres in erythroleukemia cells. Chromatin immunoprecipitation and reporter assays implicated GATA1-mediated transcriptional regulation of DKC1 in the modulation of telomerase in erythroid lineage cells. Together these results describe a novel mechanism of telomerase regulation in erythroid cells which contrasts with mechanisms centered on transcriptional regulation of TERT that are known to operate in other cell types. This is the first study to reveal a biological context in which telomerase is upregulated by DKC1 and to implicate GATA1 in telomerase regulation. The results from this study are relevant to hematopoietic disorders involving DKC1 mutations, GATA1 deregulation and/or telomerase insufficiency.
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Affiliation(s)
| | - Ashu Kumari
- Children's Cancer Institute Australia, Randwick
| | - Kathy Knezevic
- Adult Cancer Program, Prince of Wales Clinical School, Lowy Cancer Research Centre, UNSW, Sydney
| | - Julie Ai Thoms
- Adult Cancer Program, Prince of Wales Clinical School, Lowy Cancer Research Centre, UNSW, Sydney.,School of Medical Sciences, UNSW, Sydney
| | | | | | - Zara Ali
- Cancer Research Unit, Children's Medical Research Institute, Westmead
| | | | - Jonathon Marks-Bluth
- Adult Cancer Program, Prince of Wales Clinical School, Lowy Cancer Research Centre, UNSW, Sydney
| | | | - Hilda A Pickett
- Telomere Length Regulation Unit, Children's Medical Research Institute, Westmead
| | - Jonathan Morris
- The University of Sydney School of Medicine, Kolling Institute of Medical Research, St Leonards
| | - John E Pimanda
- Adult Cancer Program, Prince of Wales Clinical School, Lowy Cancer Research Centre, UNSW, Sydney.,School of Medical Sciences, UNSW, Sydney
| | - Karen L MacKenzie
- Children's Cancer Institute Australia, Randwick .,Cancer Research Unit, Children's Medical Research Institute, Westmead.,School of Women's and Children's Health, UNSW, Sydney.,Faculty of Medicine and Health, University of Sydney, Sydney, New South Wales, Australia
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116
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Bilsland AE, Liu Y, Turnbull A, Sumpton D, Stevenson K, Cairney CJ, Boyd SM, Roffey J, Jenkinson D, Keith WN. A Novel Pyrazolopyrimidine Ligand of Human PGK1 and Stress Sensor DJ1 Modulates the Shelterin Complex and Telomere Length Regulation. Neoplasia 2019; 21:893-907. [PMID: 31401411 PMCID: PMC6700475 DOI: 10.1016/j.neo.2019.07.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/19/2019] [Accepted: 07/22/2019] [Indexed: 11/15/2022] Open
Abstract
Telomere signaling and metabolic dysfunction are hallmarks of cell aging. New agents targeting these processes might provide therapeutic opportunities, including chemoprevention strategies against cancer predisposition. We report identification and characterization of a pyrazolopyrimidine compound series identified from screens focused on cell immortality and whose targets are glycolytic kinase PGK1 and oxidative stress sensor DJ1. We performed structure–activity studies on the series to develop a photoaffinity probe to deconvolute the cellular targets. In vitro binding and structural analyses confirmed these targets, suggesting that PGK1/DJ1 interact, which we confirmed by immunoprecipitation. Glucose homeostasis and oxidative stress are linked to telomere signaling and exemplar compound CRT0063465 blocked hypoglycemic telomere shortening. Intriguingly, PGK1 and DJ1 bind to TRF2 and telomeric DNA. Compound treatment modulates these interactions and also affects Shelterin complex composition, while conferring cellular protection from cytotoxicity due to bleomycin and desferroxamine. These results demonstrate therapeutic potential of the compound series.
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Affiliation(s)
- Alan E Bilsland
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow, G61 1QH, UK
| | - Yu Liu
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow, G61 1QH, UK
| | - Andrew Turnbull
- Cancer Research Technology Ltd., Wolfson Institute for Biomedical Research, The Cruciform Building, Gower Street, London, WC1E 6BT, UK
| | - David Sumpton
- Cancer Research UK Beatson Institute, Garscube Estate, Switchback Road, Bearsden, Glasgow, G61 1BD, UK
| | - Katrina Stevenson
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow, G61 1QH, UK
| | - Claire J Cairney
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow, G61 1QH, UK
| | - Susan M Boyd
- CompChem Solutions Ltd, St John's Innovation Centre, Cambridge, CB4 0WS, UK
| | - Jon Roffey
- Cancer Research Technology Ltd., Wolfson Institute for Biomedical Research, The Cruciform Building, Gower Street, London, WC1E 6BT, UK
| | - David Jenkinson
- Cancer Research Technology Ltd., Wolfson Institute for Biomedical Research, The Cruciform Building, Gower Street, London, WC1E 6BT, UK
| | - W Nicol Keith
- Institute of Cancer Sciences, University of Glasgow, Wolfson Wohl Cancer Research Centre, Garscube Estate, Switchback Road, Bearsden, Glasgow, G61 1QH, UK.
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117
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Abstract
Many recent advances have emerged in the telomere and telomerase fields. This Timeline article highlights the key advances that have expanded our views on the mechanistic underpinnings of telomeres and telomerase and their roles in ageing and disease. Three decades ago, the classic view was that telomeres protected the natural ends of linear chromosomes and that telomerase was a specific telomere-terminal transferase necessary for the replication of chromosome ends in single-celled organisms. While this concept is still correct, many diverse fields associated with telomeres and telomerase have substantially matured. These areas include the discovery of most of the key molecular components of telomerase, implications for limits to cellular replication, identification and characterization of human genetic disorders that result in premature telomere shortening, the concept that inhibiting telomerase might be a successful therapeutic strategy and roles for telomeres in regulating gene expression. We discuss progress in these areas and conclude with challenges and unanswered questions in the field.
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Affiliation(s)
- Jerry W Shay
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA.
| | - Woodring E Wright
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX, USA
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118
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Bueren JA, Quintana-Bustamante O, Almarza E, Navarro S, Río P, Segovia JC, Guenechea G. Advances in the gene therapy of monogenic blood cell diseases. Clin Genet 2019; 97:89-102. [PMID: 31231794 DOI: 10.1111/cge.13593] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 05/12/2019] [Accepted: 05/21/2019] [Indexed: 01/19/2023]
Abstract
Hematopoietic gene therapy has markedly progressed during the last 15 years both in terms of safety and efficacy. While a number of serious adverse events (SAE) were initially generated as a consequence of genotoxic insertions of gamma-retroviral vectors in the cell genome, no SAEs and excellent outcomes have been reported in patients infused with autologous hematopoietic stem cells (HSCs) transduced with self-inactivated lentiviral and gammaretroviral vectors. Advances in the field of HSC gene therapy have extended the number of monogenic diseases that can be treated with these approaches. Nowadays, evidence of clinical efficacy has been shown not only in primary immunodeficiencies, but also in other hematopoietic diseases, including beta-thalassemia and sickle cell anemia. In addition to the rapid progression of non-targeted gene therapies in the clinic, new approaches based on gene editing have been developed thanks to the discovery of designed nucleases and improved non-integrative vectors, which have markedly increased the efficacy and specificity of gene targeting to levels compatible with its clinical application. Based on advances achieved in the field of gene therapy, it can be envisaged that these therapies will soon be part of the therapeutic approaches used to treat life-threatening diseases of the hematopoietic system.
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Affiliation(s)
- Juan A Bueren
- Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Oscar Quintana-Bustamante
- Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Elena Almarza
- Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Susana Navarro
- Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Paula Río
- Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - José C Segovia
- Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
| | - Guillermo Guenechea
- Division of Hematopoietic Innovative Therapies, Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Madrid, Spain.,Centro de Investigación Biomédica en Red de Enfermedades Raras (CIBERER), Instituto de Investigaciones Sanitarias Fundación Jiménez Díaz (IIS-FJD), Madrid, Spain
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119
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Zhang L, Li S, Chen L, Li J, Zhang Z, Yang Y, Wang X, Liu J. Cerebellar fastigial nucleus electrical stimulatin protects against cerebral ischemic damage by upregulating telomerase activity. Restor Neurol Neurosci 2019; 37:131-141. [PMID: 30988241 DOI: 10.3233/rnn-180876] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
BACKGROUND Cerebellar fastigial nucleus electrical stimulation (FNS) in rats has been shown to protect against brain ischemia/reperfusion (I/R) damage. Activation of telomerase has been reported to provide neuroprotection in animal models of stroke. OBJECTIVE The aim of this study was to explore whether precondition FNS increases the expression of telomerase reverse transcriptase (TERT) and telomerase activity in rats after cerebral I/R injury. METHODS One day after continuous stimulation of the fastigial cerebellar nucleus for 1 h, adult male Sprague Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h and reperfusion for 24 h, 48 h and 72 h, while the I/R control groups received the same treatment without FNS. Ischemic lesion volumes were measured following TTC staining. The number of apoptotic cells was measured by using TUNEL assays. Subsequently, telomerase activity was examined by using TRAP-silver staining. Additionally, the expression level of TERT mRNA was assessed by using real-time fluorescence quantitative PCR. Finally, the expression of TERT protein was measured by using Western blotting. RESULTS The results of our study demonstrated that FNS significantly decreased infarct volumes and improved neurological deficits when compared with the I/R control group. The telomerase activity in the I/R + FNS group was significantly increased compared with that in the I/R control group, particularly in the 24 h reperfusion subgroup (P < 0.05). FNS treatment significantly decreased the number of TUNEL-positive cells when compared with that in the I/R control group. Expression of TERT gradually increased, with the peak occurring after or before 48 h reperfusion and the 24 h and 72 h reperfusion subgroups demonstrating higher expression than each I/R control group (P < 0.05). CONCLUSIONS Our results show that pre-FNS exerts neuroprotective effects that may be achieved by upregulating the expression of TERT and then by increasing telomerase activity.
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Affiliation(s)
- Lei Zhang
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University in Nanning, China
| | - Shenghua Li
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University in Nanning, China
| | - Lan Chen
- Department of Internal Medicine, The Second Affiliated Hospital of Guangxi Medical University in Nanning, China
| | - Jinpin Li
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University in Nanning, China
| | - Zhaoxia Zhang
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University in Nanning, China
| | - Yi Yang
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University in Nanning, China
| | - Xiaoling Wang
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University in Nanning, China
| | - Jingli Liu
- Department of Neurology, The First Affiliated Hospital of Guangxi Medical University in Nanning, China
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120
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Quantitative Biology of Human Shelterin and Telomerase: Searching for the Weakest Point. Int J Mol Sci 2019; 20:ijms20133186. [PMID: 31261825 PMCID: PMC6651453 DOI: 10.3390/ijms20133186] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/12/2019] [Accepted: 06/27/2019] [Indexed: 02/06/2023] Open
Abstract
The repetitive telomeric DNA at chromosome ends is protected from unwanted repair by telomere-associated proteins, which form the shelterin complex in mammals. Recent works have provided new insights into the mechanisms of how human shelterin assembles and recruits telomerase to telomeres. Inhibition of telomerase activity and telomerase recruitment to chromosome ends is a promising target for anticancer therapy. Here, we summarize results of quantitative assessments and newly emerged structural information along with the status of the most promising approaches to telomerase inhibition in cancer cells. We focus on the mechanism of shelterin assembly and the mechanisms of how shelterin affects telomerase recruitment to telomeres, addressing the conceptual dilemma of how shelterin allows telomerase action and regulates other essential processes. We evaluate how the identified critical interactions of telomerase and shelterin might be elucidated in future research of new anticancer strategies.
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121
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The Role of Telomerase and Telomeres in Interstitial Lung Diseases: From Molecules to Clinical Implications. Int J Mol Sci 2019; 20:ijms20122996. [PMID: 31248154 PMCID: PMC6627617 DOI: 10.3390/ijms20122996] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Revised: 06/12/2019] [Accepted: 06/15/2019] [Indexed: 02/07/2023] Open
Abstract
Telomeres are distal chromosome regions associated with specific protein complexes that protect the chromosome against degradation and aberrations. Telomere maintenance capacity is an essential indication of healthy cell populations, and telomere damage is observed in processes such as malignant transformation, apoptosis, or cell senescence. At a cellular level, telomere damage may result from genotoxic stress, decreased activity of telomerase enzyme complex, dysfunction of shelterin proteins, or changes in expression of telomere-associated RNA such as TERRA. Clinical evidence suggests that mutation of telomerase genes (Tert/Terc) are associated with increased risk of congenital as well as age-related diseases (e.g., pneumonitis, idiopathic pulmonary fibrosis (IPF), dyskeratosis congenita, emphysema, nonspecific interstitial pneumonia, etc.). Thus, telomere length and maintenance can serve as an important prognostic factor as well as a potential target for new strategies of treatment for interstitial lung diseases (ILDs) and associated pulmonary pathologies.
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122
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Mei M, Zhang M. Non-coding RNAs in Natural Killer/T-Cell Lymphoma. Front Oncol 2019; 9:515. [PMID: 31263681 PMCID: PMC6584837 DOI: 10.3389/fonc.2019.00515] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Accepted: 05/29/2019] [Indexed: 12/19/2022] Open
Abstract
Natural killer/T-cell lymphoma (NKTCL) is a rare and aggressive subtype of non-Hodgkin's lymphoma that is associated with a poor outcome. Non-coding RNAs (ncRNAs), which account for 98% of human RNAs, lack the function of encoding proteins but instead have the important function of regulating gene expression, including transcription, translation, RNA splicing, editing, and turnover. However, the roles and mechanisms of aberrantly expressed ncRNAs in NKTCL are not fully clear. Aberrant expressions of microRNA (miRNAs) affect the PI3K/AKT signaling pathways (miRNA-21, miRNA-155, miRNA-150, miRNA-142, miRNA-494), NF-κB (miRNA-146a, miRNA-155) and cell cycle signaling pathways to regulate cell function. Moreover, Epstein-Barr virus (EBV) encoded miRNAs and EBV oncoprotein LMP-1 regulated the expression of cellular genes that induce invasion, metastasis, cell cycle progression and cellular transformation. In addition, NKTCL-associated Long non-coding RNA (lncRNA) ZFAS1 regulated certain pathways and lncRNA MALAT1 acted as a predictive marker. This review article provides an overview of ncRNAs associated with NKTCL, summarizes the function of significantly differentially expressed hotspot non-coding RNAs that contribute to the pathogenesis, diagnoses, treatment and prognosis of NKTCL and discusses the relevance of these ncRNAs to clinical practice.
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Affiliation(s)
- Mei Mei
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China.,The Academy of Medical Science, Zhengzhou University, Zhengzhou, China
| | - Mingzhi Zhang
- Department of Oncology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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123
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Lee YH, Chen YY, Yeh YL, Wang YJ, Chen RJ. Stilbene Compounds Inhibit Tumor Growth by the Induction of Cellular Senescence and the Inhibition of Telomerase Activity. Int J Mol Sci 2019; 20:ijms20112716. [PMID: 31159515 PMCID: PMC6600253 DOI: 10.3390/ijms20112716] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 12/17/2022] Open
Abstract
Cellular senescence is a state of cell cycle arrest characterized by a distinct morphology, gene expression pattern, and secretory phenotype. It can be triggered by multiple mechanisms, including those involved in telomere shortening, the accumulation of DNA damage, epigenetic pathways, and the senescence-associated secretory phenotype (SASP), and so on. In current cancer therapy, cellular senescence has emerged as a potent tumor suppression mechanism that restrains proliferation in cells at risk for malignant transformation. Therefore, compounds that stimulate the growth inhibition effects of senescence while limiting its detrimental effects are believed to have great clinical potential. In this review article, we first review the current knowledge of the pro- and antitumorigeneic functions of senescence and summarize the key roles of telomerase in the regulation of senescence in tumors. Second, we review the current literature regarding the anticancer effects of stilbene compounds that are mediated by the targeting of telomerase and cell senescence. Finally, we provide future perspectives on the clinical utilization of stilbene compounds, especially resveratrol and pterostilbene, as novel cancer therapeutic remedies. We conclude and propose that stilbene compounds may induce senescence and may potentially be used as the therapeutic or adjuvant agents for cancers with high telomerase activity.
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Affiliation(s)
- Yu-Hsuan Lee
- Department of Food Safety/Hygiene and Risk Management, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan.
| | - Yu-Ying Chen
- Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan.
| | - Ya-Ling Yeh
- Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan.
| | - Ying-Jan Wang
- Department of Environmental and Occupational Health, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan.
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 40402, Taiwan.
| | - Rong-Jane Chen
- Department of Food Safety/Hygiene and Risk Management, College of Medicine, National Cheng Kung University, Tainan 70428, Taiwan.
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124
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Hereditary myeloid malignancies. Best Pract Res Clin Haematol 2019; 32:163-176. [DOI: 10.1016/j.beha.2019.05.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 05/01/2019] [Indexed: 12/18/2022]
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125
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Watanabe M, Yamamoto G, Fujiyoshi K, Akagi Y, Kakuta M, Nishimura Y, Akagi K. Development of metachronous rectal cancers in a young man with dyskeratosis congenita: a case report. J Med Case Rep 2019; 13:117. [PMID: 31027506 PMCID: PMC6486685 DOI: 10.1186/s13256-019-2044-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Accepted: 03/07/2019] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND DKC1 (dyskerin pseudouridine synthase 1) is a causative gene for X-linked dyskeratosis congenita. Approximately 8% of patients with dyskeratosis congenita have malignancy, but information about the development of malignancy in patients with dyskeratosis congenita is limited. CASE PRESENTATION A young Japanese patient with bone marrow failure developed metachronous rectal adenocarcinomas at the ages of 16 and 18 years. He had no family history of cancer. Microsatellite instability testing with rectal tumor tissue demonstrated low-level microsatellite instability. To clarify whether any cancer susceptibility genes were involved in the development of rectal cancer, RNA sequencing was performed. Cancer-related genes were assessed, and a c.361A>G (p.Ser121Gly) germline variant was detected in DKC1. The same missense variant was previously reported in two patients with dyskeratosis congenita as a pathogenic variant, but those patients did not develop malignancies. CONCLUSIONS Our patient developed rectal cancer at an early age of onset compared with the previously reported typical onset age of patients with dyskeratosis congenita. DKC1 might be involved in predisposition to colorectal cancer in young adulthood; therefore, appropriate surveillance may be considered.
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Affiliation(s)
- Motoko Watanabe
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Gou Yamamoto
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | | | - Yoshito Akagi
- Department of Surgery, Kurume University, Fukuoka, Japan
| | - Miho Kakuta
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan
| | - Yoji Nishimura
- Division of Gastroenterological Surgery, Saitama Cancer Center, Saitama, Japan
| | - Kiwamu Akagi
- Department of Molecular Diagnosis and Cancer Prevention, Saitama Cancer Center, 780 Komuro, Ina-machi, Kitaadachi-gun, Saitama, 362-0806, Japan.
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126
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Strnadova K, Sandera V, Dvorankova B, Kodet O, Duskova M, Smetana K, Lacina L. Skin aging: the dermal perspective. Clin Dermatol 2019; 37:326-335. [PMID: 31345320 DOI: 10.1016/j.clindermatol.2019.04.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The world population of adults aged 60 years or more is increasing globally, and this development can impact skin disease morbidity and mortality, as well as being reflected in the health care system organization. There is substantial evidence that the burden from a remarkable number of skin nonmalignant and malignant conditions is greater in the elderly. Dermatologic research and clinical education in dermatology should focus on both challenges and opportunities created by aging. Skin aging due to intrinsic and extrinsic factors can alter significantly epidermal and dermal structure and functions. Dermal aging can be linked to a great number of complications in routine dermatologic conditions, with slow healing as an example of a severe complication in the elderly. This may be attributed to aged dermal fibroblasts modifying the tissue microenvironment via a shift in their soluble factors and extracellular matrix repertoire. This senescence-associated secretory phenotype can explain the particular proclivity of aged skin to develop malignancies.
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Affiliation(s)
- Karolina Strnadova
- Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic; BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic
| | - Vojtech Sandera
- Department of Plastic Surgery, Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Barbora Dvorankova
- Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic; BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic
| | - Ondrej Kodet
- Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic; BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic; Department of Dermatovenereology, First Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Marketa Duskova
- Department of Plastic Surgery, Third Faculty of Medicine, Charles University, Prague, Czech Republic
| | - Karel Smetana
- Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic; BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic
| | - Lukas Lacina
- Institute of Anatomy, First Faculty of Medicine, Charles University, Prague, Czech Republic; BIOCEV, First Faculty of Medicine, Charles University, Vestec, Czech Republic; Department of Dermatovenereology, First Faculty of Medicine, Charles University, Prague, Czech Republic.
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127
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Liu T, Gonzalez De Los Santos F, Zhao Y, Wu Z, Rinke AE, Kim KK, Phan SH. Telomerase reverse transcriptase ameliorates lung fibrosis by protecting alveolar epithelial cells against senescence. J Biol Chem 2019; 294:8861-8871. [PMID: 31000627 DOI: 10.1074/jbc.ra118.006615] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 04/11/2019] [Indexed: 11/06/2022] Open
Abstract
Mutations in the genes encoding telomerase reverse transcriptase (TERT) and telomerase's RNA components as well as shortened telomeres are risk factors for idiopathic pulmonary fibrosis, where repetitive injury to the alveolar epithelium is considered a key factor in pathogenesis. Given the importance of TERT in stem cells, we hypothesized that TERT plays an important role in epithelial repair and that its deficiency results in exacerbation of fibrosis by impairing this repair/regenerative process. To evaluate the role of TERT in epithelial cells, we generated type II alveolar epithelial cell (AECII)-specific TERT conditional knockout (SPC-Tert cKO) mice by crossing floxed Tert mice with inducible SPC-driven Cre mice. SPC-Tert cKO mice did not develop pulmonary fibrosis spontaneously up to 9 months of TERT deficiency. However, upon bleomycin treatment, they exhibited enhanced lung injury, inflammation, and fibrosis compared with control mice, accompanied by increased pro-fibrogenic cytokine expression but without a significant effect on AECII telomere length. Moreover, selective TERT deficiency in AECII diminished their proliferation and induced cellular senescence. These findings suggest that AECII-specific TERT deficiency enhances pulmonary fibrosis by heightening susceptibility to bleomycin-induced epithelial injury and diminishing epithelial regenerative capacity because of increased cellular senescence. We confirmed evidence for increased AECII senescence in idiopathic pulmonary fibrosis lungs, suggesting potential clinical relevance of the findings from our animal model. Our results suggest that TERT has a protective role in AECII, unlike its pro-fibrotic activity, observed previously in fibroblasts, indicating that TERT's role in pulmonary fibrosis is cell type-specific.
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Affiliation(s)
| | | | | | - Zhe Wu
- From the Departments of Pathology and
| | | | - Kevin K Kim
- Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan 48109
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128
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Ma F, Wang TT, Jiang L, Zhang CY. Ultrasensitive detection of telomerase activity in lung cancer cells with quencher-free molecular beacon-assisted quadratic signal amplification. Anal Chim Acta 2019; 1053:122-130. [DOI: 10.1016/j.aca.2018.11.058] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2018] [Revised: 11/27/2018] [Accepted: 11/30/2018] [Indexed: 10/27/2022]
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129
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Mohanty P, Jadhav P, Shanmukhaiah C, Kumar S, Vundinti BR. A novel DKC1 gene mutation c.1177 A>T (p.I393F) in a case of dyskeratosis congenita with severe telomere shortening. Int J Dermatol 2019; 58:1468-1471. [PMID: 30868555 DOI: 10.1111/ijd.14424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 11/19/2018] [Accepted: 02/14/2019] [Indexed: 11/28/2022]
Affiliation(s)
- Purvi Mohanty
- Department of Cytogenetics, National Institute of Immunohaematology, Mumbai, India
| | - Prajakta Jadhav
- Department of Cytogenetics, National Institute of Immunohaematology, Mumbai, India
| | | | - Selvaa Kumar
- School of Biotechnology and Bioinformatics, D. Y. Patil University, Navi Mumbai, Maharashtra, India
| | - Babu Rao Vundinti
- Department of Cytogenetics, National Institute of Immunohaematology, Mumbai, India
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130
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Transcriptome-wide profiling of multiple RNA modifications simultaneously at single-base resolution. Proc Natl Acad Sci U S A 2019; 116:6784-6789. [PMID: 30872485 PMCID: PMC6452723 DOI: 10.1073/pnas.1817334116] [Citation(s) in RCA: 146] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
The field of RNA modification would be significantly advanced by the development of sensitive, accurate, single-base resolution methods for profiling multiple common RNA modifications in the same RNA molecule. Our work provides several advances toward that goal, including (i) quantitative methods for profiling Ψ sites at true base-pair resolution transcriptome-wide, (ii) a chemical understanding of our observed Ψ-dependent deletion signature, (iii) improved methods for profiling m5C and m1A, and (iv) a coupling of these methods for the simultaneous detection of all three modifications in the same RNA. Together, the combinatorial ability and relative ease of execution provided by this procedure should greatly forward epitranscriptome studies involving these three very common RNA modifications. The breadth and importance of RNA modifications are growing rapidly as modified ribonucleotides can impact the sequence, structure, function, stability, and fate of RNAs and their interactions with other molecules. Therefore, knowing cellular RNA modifications at single-base resolution could provide important information regarding cell status and fate. A current major limitation is the lack of methods that allow the reproducible profiling of multiple modifications simultaneously, transcriptome-wide and at single-base resolution. Here we developed RBS-Seq, a modification of RNA bisulfite sequencing that enables the sensitive and simultaneous detection of m5C, Ψ, and m1A at single-base resolution transcriptome-wide. With RBS-Seq, m5C and m1A are accurately detected based on known signature base mismatches and are detected here simultaneously along with Ψ sites that show a 1–2 base deletion. Structural analyses revealed the mechanism underlying the deletion signature, which involves Ψ-monobisulfite adduction, heat-induced ribose ring opening, and Mg2+-assisted reorientation, causing base-skipping during cDNA synthesis. Detection of each of these modifications through a unique chemistry allows high-precision mapping of all three modifications within the same RNA molecule, enabling covariation studies. Application of RBS-Seq on HeLa RNA revealed almost all known m5C, m1A, and ψ sites in tRNAs and rRNAs and provided hundreds of new m5C and Ψ sites in noncoding RNAs and mRNAs. However, our results diverge greatly from earlier work, suggesting ∼10-fold fewer m5C sites in noncoding and coding RNAs and the absence of substantial m1A in mRNAs. Taken together, the approaches and refined datasets in this work will greatly enable future epitranscriptome studies.
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131
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Posttranscriptional modulation of TERC by PAPD5 inhibition rescues hematopoietic development in dyskeratosis congenita. Blood 2019; 133:1308-1312. [PMID: 30728146 DOI: 10.1182/blood-2018-11-885368] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Accepted: 01/18/2019] [Indexed: 12/14/2022] Open
Abstract
Reduced levels of TERC, the telomerase RNA component, cause dyskeratosis congenita (DC) in patients harboring mutations in TERC, PARN, NOP10, NHP2, NAF1, or DKC1. Inhibition of the noncanonical poly(A) polymerase PAPD5, or the exosome RNA degradation complex, partially restores TERC levels in immortalized DKC1 mutant cells, but it remains unknown if modulation of posttranscriptional processing of TERC could improve hematopoietic output in DC. We used human embryonic stem cells (hESCs) with a common dyskerin mutation (DKC1_A353V), which have defective telomere maintenance and reduced definitive hematopoietic potential, to understand the effects of reducing EXOSC3 activity, or silencing PAPD5-mediated oligoadenylation, on hematopoietic progenitor specification and function in DC. Reduction of EXOSC3 or PAPD5 levels in DKC1 mutant hESCs led to functional improvements in TERC levels and telomerase activity, with concomitant telomere elongation and reduced levels of DNA damage signaling. Interestingly, the silencing of PAPD5, but not EXOSC3, significantly restored definitive hematopoietic potential in DKC1 mutant cells. Mechanistically, we show that PAPD5 inhibition is sustained in differentiated CD34+ cells, with a concomitant increase in mature, functional, forms of TERC, indicating that regulation of PAPD5 is a potential strategy to reverse hematologic dysfunction in DC patients.
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132
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Courtwright AM, El-Chemaly S. Telomeres in Interstitial Lung Disease: The Short and the Long of It. Ann Am Thorac Soc 2019; 16:175-181. [PMID: 30540921 PMCID: PMC6376948 DOI: 10.1513/annalsats.201808-508cme] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2018] [Accepted: 09/25/2018] [Indexed: 01/01/2023] Open
Abstract
Telomeres are repetitive nucleotide sequences that cap linear chromosomes, thereby limiting progressive chromosomal shortening during cell replication. In conjunction with environmental factors, common single-nucleotide polymorphisms and rare and ultra-rare telomere-related mutations are associated with accelerated telomere shortening resulting in organ dysfunction, including interstitial lung disease (ILD). The most common telomere-related mutation-associated ILD is idiopathic pulmonary fibrosis (IPF). Up to one-third of individuals with familial IPF have shortened telomeres and/or carry a telomere-related mutation, and 1 in 10 individuals with sporadic IPF have telomere-related mutations. Regardless of ILD phenotype, individuals with short telomeres and/or known telomere-related mutations have more rapid disease progression and shorter lung transplant-free survival. Management should include initiation of antifibrotic agents for those with an IPF phenotype and early referral to a transplant center. Patients with ILD being considered for transplant should be screened for short telomeres if there is a significant family history of pulmonary fibrosis or evidence of extrapulmonary organ dysfunction associated with a short telomere syndrome. Post-transplant management of recipients with telomere-related mutations should include careful adjustment of immunosuppression regimens on the basis of bone marrow reserve. Data on the impact of shortened telomeres on post-transplant outcomes, however, remain mixed.
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Affiliation(s)
- Andrew M. Courtwright
- Division of Pulmonary and Critical Care Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania; and
| | - Souheil El-Chemaly
- Division of Pulmonary and Critical Care Medicine, Brigham and Women’s Hospital, Boston, Massachusetts
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133
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Turner KJ, Vasu V, Griffin DK. Telomere Biology and Human Phenotype. Cells 2019; 8:cells8010073. [PMID: 30669451 PMCID: PMC6356320 DOI: 10.3390/cells8010073] [Citation(s) in RCA: 198] [Impact Index Per Article: 39.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2018] [Revised: 01/14/2019] [Accepted: 01/16/2019] [Indexed: 12/15/2022] Open
Abstract
Telomeres are nucleoprotein structures that cap the end of each chromosome arm and function to maintain genome stability. The length of telomeres is known to shorten with each cell division and it is well-established that telomere attrition is related to replicative capacity in vitro. Moreover, telomere loss is also correlated with the process of aging in vivo. In this review, we discuss the mechanisms that lead to telomere shortening and summarise telomere homeostasis in humans throughout a lifetime. In addition, we discuss the available evidence that shows that telomere shortening is related to human aging and the onset of age-related disease.
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Affiliation(s)
- Kara J Turner
- University of Kent, School of Biosciences, Giles Lane, Canterbury, Kent, CT2-7NJ, UK.
| | - Vimal Vasu
- University of Kent, School of Biosciences, Giles Lane, Canterbury, Kent, CT2-7NJ, UK.
- Department of Child Health, East Kent Hospitals University Foundation NHS Trust, William Harvey Hospital, Ashford, Kent, TN24-0LZ, UK.
| | - Darren K Griffin
- University of Kent, School of Biosciences, Giles Lane, Canterbury, Kent, CT2-7NJ, UK.
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134
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Demina IA, Semchenkova AA, Kagirova ZR, Popov AM. Flow cytometric measurement of absolute telomere length. ACTA ACUST UNITED AC 2019. [DOI: 10.24287/1726-1708-2018-17-4-68-74] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The length of the end of chromosomes – telomeres is a dynamic and constant characterizes cellular aging process. Measurement of telomere length (TL) and its connection with the diagnosis, course, prognosis and treatment of a number of diseases in recent years, is of great interest for researchers. The methods used for this are varied and are primarily by molecular biological. Variability of methodological approaches, the lack of a common standard of measurement TL measurements in absolute and relative terms: all this leads to results that cannot be compared with each other. The aim of this work is the development of data conversion algorithm is obtained by flow cytometry in absolute telomere length, expressed in kilobases (kb). The study was conducted from venous blood of children 2–3 years of age (8 healthy children and 3 patients with dyskeratosis congenita). As control material used cell line 1301 (ATCC, UK). Determination of relative telomere length was performed by using a set FlowFISH Telomere PNA Kit / FITC (DakoCytomation, Glostrup, Denmark). RTL code and the absolute length of telomeres were calculated for each study participant. Data on the length of patients telomere were compared with data on TL healthy children of appropriate age. RTL average value for healthy children 2–3 years was 30.1, and an absolute telomere length – 15.56 kb. Telomere length patients with dyskeratosis congenita was significantly shorter (RTL 1.4–4.3, the absolute value of TL 0.3–2.4 kb). The algorithm conversion molecular fluorescence equivalent in absolute TL is universal and can be used in any laboratory equipped with a flow cytometer. The resulting data TL can be compared with the data expressed in absolute units and obtained by any other method.
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Affiliation(s)
- I. A. Demina
- Dmitriy Rogachev National Medical Research Center of Pediatric Hematology, Oncology, Immunology Ministry of Healthcare of Russian Federation
| | - A. A. Semchenkova
- Dmitriy Rogachev National Medical Research Center of Pediatric Hematology, Oncology, Immunology Ministry of Healthcare of Russian Federation
| | - Z. R. Kagirova
- Russian National Research Medical University named after N.I. Pirogov
| | - A. M. Popov
- Dmitriy Rogachev National Medical Research Center of Pediatric Hematology, Oncology, Immunology Ministry of Healthcare of Russian Federation
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135
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Laudadio I, Orso F, Azzalin G, Calabrò C, Berardinelli F, Coluzzi E, Gioiosa S, Taverna D, Sgura A, Carissimi C, Fulci V. AGO2 promotes telomerase activity and interaction between the telomerase components TERT and TERC. EMBO Rep 2018; 20:embr.201845969. [PMID: 30591524 DOI: 10.15252/embr.201845969] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 11/16/2018] [Accepted: 11/26/2018] [Indexed: 12/31/2022] Open
Abstract
Telomerase reverse transcriptase (TERT) and telomerase RNA component (TERC) constitute the core telomerase enzyme that maintains the length of telomeres. Telomere maintenance is affected in a broad range of cancer and degenerative disorders. Taking advantage of gain- and loss-of-function approaches, we show that Argonaute 2 (AGO2) promotes telomerase activity and stimulates the association between TERT and TERC AGO2 depletion results in shorter telomeres as well as in lower proliferation rates in vitro and in vivo We also demonstrate that AGO2 interacts with TERC and with a newly identified sRNA (terc-sRNA), arising from the H/ACA box of TERC Notably, terc-sRNA is sufficient to enhance telomerase activity when overexpressed. Analyses of sRNA-Seq datasets show that terc-sRNA is detected in primary human tissues and increases in tumors as compared to control tissues. Collectively, these data uncover a new layer of complexity in the regulation of telomerase activity by AGO2 and might lay the foundation for new therapeutic targets in tumors and telomere diseases.
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Affiliation(s)
- Ilaria Laudadio
- Department of Molecular Medicine, "Sapienza" University of Rome, Rome, Italy
| | - Francesca Orso
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Turin, Turin, Italy
| | - Gianluca Azzalin
- Department of Molecular Medicine, "Sapienza" University of Rome, Rome, Italy
| | - Carlo Calabrò
- Department of Molecular Medicine, "Sapienza" University of Rome, Rome, Italy
| | | | - Elisa Coluzzi
- Department of Science, University of Rome "Roma Tre", Rome, Italy
| | - Silvia Gioiosa
- CNR, Istituto di Biomembrane, Bioenergetica e Biotecnologie Molecolari (IBIOM), Bari, Italy
| | - Daniela Taverna
- Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Turin, Turin, Italy
| | - Antonella Sgura
- Department of Science, University of Rome "Roma Tre", Rome, Italy
| | - Claudia Carissimi
- Department of Molecular Medicine, "Sapienza" University of Rome, Rome, Italy
| | - Valerio Fulci
- Department of Molecular Medicine, "Sapienza" University of Rome, Rome, Italy
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136
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Portillo AM, Varela E, García-Velasco JA. Mathematical model to study the aging of the human follicle according to the telomerase activity. J Theor Biol 2018; 462:446-454. [PMID: 30502407 DOI: 10.1016/j.jtbi.2018.11.036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Revised: 11/26/2018] [Accepted: 11/28/2018] [Indexed: 12/27/2022]
Abstract
The aim of this work is to study the aging rate at which human follicles reach the preovulatory state. To this end, both telomere length and telomerase activity effects on granulosa cells (GCs) aging has been studied. GCs are somatic cells which determine the development of the oocyte. A human preantral follicle takes approximately 85 days to achieve the preovulatory size, going through several stages (Gougeon, 1996). The telomere length of GCs of each class of follicles, during folliculogenesis, are modelled using a chemical master equation formalism similar to the one in Wesch et al. (2016). Seven differential ordinary systems of equations, corresponding to seven stages of the follicule maturation, concatenated in time, are considered. The mitotic and death rates are approximated by using the mean number of GCs in each class of follicles and the time they remain on each stage. The influence of different telomerase activity rates and the telomere shortening of the preovulatory follicle is studied. Some cases of infertility are associated with low levels of telomerase activity and short telomeres in GCs. The method aims at understanding how low levels of telomerase activity in preovulatory stages lead to the accumulation of aged GCs. In the case of higher telomerase activities, the mathematical model predicts a more juvenile outcome in preovulatory follicles. Juvenile GCs, could be critical for embryo development if the oocyte were fertilized, since GCs, transformed in corpus luteum, must divide and increase their size (Alila and Hansel, 1984) to sustain early pregnancy (Csapo et al., 1972).
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Affiliation(s)
- A M Portillo
- IMUVA, Departamento de Matemática Aplicada, Escuela de Ingenierías Industriales, Universidad de Valladolid, Spain.
| | - E Varela
- IVIRMA, Madrid. Av del Talgo, Madrid, 68. 28023, Spain; IdiPaz, Calle de Pedro Rico, Madrid, 6. 28029, Spain.
| | - J A García-Velasco
- IVIRMA, Madrid. Av del Talgo, Madrid, 68. 28023, Spain; IdiPaz, Calle de Pedro Rico, Madrid, 6. 28029, Spain; Rey Juan Carlos University, Madrid, Spain.
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137
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Ivanyi-Nagy R, Ahmed SM, Peter S, Ramani PD, Ong PF, Dreesen O, Dröge P. The RNA interactome of human telomerase RNA reveals a coding-independent role for a histone mRNA in telomere homeostasis. eLife 2018; 7:40037. [PMID: 30355447 PMCID: PMC6249008 DOI: 10.7554/elife.40037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 10/24/2018] [Indexed: 12/26/2022] Open
Abstract
Telomerase RNA (TR) provides the template for DNA repeat synthesis at telomeres and is essential for genome stability in continuously dividing cells. We mapped the RNA interactome of human TR (hTR) and identified a set of non-coding and coding hTR-interacting RNAs, including the histone 1C mRNA (HIST1H1C). Disruption of the hTR-HIST1H1C RNA association resulted in markedly increased telomere elongation without affecting telomerase enzymatic activity. Conversely, over-expression of HIST1H1C led to telomere attrition. By using a combination of mutations to disentangle the effects of histone 1 RNA synthesis, protein expression, and hTR interaction, we show that HIST1H1C RNA negatively regulates telomere length independently of its protein coding potential. Taken together, our data provide important insights into a surprisingly complex hTR-RNA interaction network and define an unexpected non-coding RNA role for HIST1H1C in regulating telomere length homeostasis, thus offering a glimpse into the mostly uncharted, vast space of non-canonical messenger RNA functions.
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Affiliation(s)
- Roland Ivanyi-Nagy
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Syed Moiz Ahmed
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | - Sabrina Peter
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
| | | | - Peh Fern Ong
- Cell Ageing, Skin Research Institute Singapore, Singapore, Singapore
| | - Oliver Dreesen
- Cell Ageing, Skin Research Institute Singapore, Singapore, Singapore
| | - Peter Dröge
- School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.,Nanyang Institute of Structural Biology, Nanyang Technological University, Singapore, Singapore
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138
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Assani G, Xiong Y, Zhou F, Zhou Y. Effect of therapies-mediated modulation of telomere and/or telomerase on cancer cells radiosensitivity. Oncotarget 2018; 9:35008-35025. [PMID: 30405890 PMCID: PMC6201854 DOI: 10.18632/oncotarget.26150] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Accepted: 07/31/2018] [Indexed: 12/11/2022] Open
Abstract
Cancer is one of the leading causes of death in the world. Many strategies of cancer treatment such as radiotherapy which plays a key role in cancer treatment are developed and used nowadays. However, the side effects post-cancer radiotherapy and cancer radioresistance are two major causes of the limitation of cancer radiotherapy effectiveness in the cancer patients. Moreover, reduction of the limitation of cancer radiotherapy effectiveness by reducing the side effects post-cancer radiotherapy and cancer radioresistance is the aim of several radiotherapy-oncologic teams. Otherwise, Telomere and telomerase are two cells components which play an important role in cancer initiation, cancer progression and cancer therapy resistance such as radiotherapy resistance. For resolving the problems of the limitation of cancer radiotherapy effectiveness especially the cancer radio-resistance problems, the radio-gene-therapy strategy which is the use of gene-therapy via modulation of gene expression combined with radiotherapy was developed and used as a new strategy to treat the patients with cancer. In this review, we summarized the information concerning the implication of telomere and telomerase modulation in cancer radiosensitivity.
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Affiliation(s)
- Ganiou Assani
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Cancer Clinical Study Center, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Key Laboratory of Tumor Biology Behaviors, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yudi Xiong
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Cancer Clinical Study Center, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Key Laboratory of Tumor Biology Behaviors, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Fuxiang Zhou
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Cancer Clinical Study Center, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Key Laboratory of Tumor Biology Behaviors, Zhongnan Hospital of Wuhan University, Wuhan, China
| | - Yunfeng Zhou
- Department of Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Cancer Clinical Study Center, Zhongnan Hospital of Wuhan University, Wuhan, China
- Hubei Key Laboratory of Tumor Biology Behaviors, Zhongnan Hospital of Wuhan University, Wuhan, China
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139
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Kosebent EG, Uysal F, Ozturk S. Telomere length and telomerase activity during folliculogenesis in mammals. J Reprod Dev 2018; 64:477-484. [PMID: 30270279 PMCID: PMC6305847 DOI: 10.1262/jrd.2018-076] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Telomeres are repetitive non-coding DNA sequences located at the ends of chromosomes in eukaryotic cells. Their most important function is to protect chromosome ends from being recognized
as DNA damage. They are also implicated in meiosis and synapse formation. The length of telomeres inevitably shortens at the end of each round of DNA replication and, also, as a consequence
of the exposure to oxidative stress and/or genotoxic agents. The enzyme telomerase contributes to telomere lengthening. It has been reported that telomerase is exclusively expressed in germ
cells, granulosa cells, early embryos, stem cells, and various types of cancerous cells. Granulosa cells undergo many mitotic divisions and either granulosa cells or oocytes are exposed to a
variety of genotoxic agents throughout folliculogenesis; thus, telomerase plays an important role in the maintenance of telomere length. In this review article, we have comprehensively
evaluated the studies focusing on the regulation of telomerase expression and activity, as well as telomere length, during folliculogenesis from primordial to antral follicles, in several
mammalian species including mice, bovines, and humans. Also, the possible relationships between female infertility caused by follicular development defects and alterations in the telomeres
and/or telomerase activity are discussed.
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Affiliation(s)
- Esra Gozde Kosebent
- Department of Histology and Embryology, Akdeniz University School of Medicine, Antalya 07070, Turkey
| | - Fatma Uysal
- Department of Histology and Embryology, Ankara University School of Medicine, Ankara, Turkey
| | - Saffet Ozturk
- Department of Histology and Embryology, Akdeniz University School of Medicine, Antalya 07070, Turkey
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140
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Jose SS, Tidu F, Burilova P, Kepak T, Bendickova K, Fric J. The Telomerase Complex Directly Controls Hematopoietic Stem Cell Differentiation and Senescence in an Induced Pluripotent Stem Cell Model of Telomeropathy. Front Genet 2018; 9:345. [PMID: 30210531 PMCID: PMC6123533 DOI: 10.3389/fgene.2018.00345] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 08/09/2018] [Indexed: 01/16/2023] Open
Abstract
Telomeropathies are rare disorders associated with impaired telomere length control mechanisms that frequently result from genetic mutations in the telomerase complex. Dyskeratosis congenita is a congenital progressive telomeropathy in which mutation in the telomerase RNA component (TERC) impairs telomere maintenance leading to accelerated cellular senescence and clinical outcomes resembling premature aging. The most severe clinical feature is perturbed hematopoiesis and bone-marrow failure, but the underlying mechanisms are not fully understood. Here, we developed a model of telomerase function imbalance using shRNA to knockdown TERC expression in human induced pluripotent stem cells (iPSCs). We then promoted in vitro hematopoiesis in these cells to analyze the effects of TERC impairment. Reduced TERC expression impaired hematopoietic stem-cell (HSC) differentiation and increased the expression of cellular senescence markers and production of reactive oxygen species. Interestingly, telomere length was unaffected in shTERC knockdown iPSCs, leading to conclusion that the phenotype is controlled by non-telomeric functions of telomerase. We then assessed the effects of TERC-depletion in THP-1 myeloid cells and again observed reduced hematopoietic and myelopoietic differentiative potential. However, these cells exhibited impaired telomerase activity as verified by accelerated telomere shortening. shTERC-depleted iPSC-derived and THP-1-derived myeloid precursors had lower phagocytic capacity and increased ROS production, indicative of senescence. These findings were confirmed using a BIBR1532 TERT inhibitor, suggesting that these phenotypes are dependent on telomerase function but not directly linked to telomere length. These data provide a better understanding of the molecular processes driving the clinical signs of telomeropathies and identify novel roles of the telomerase complex other than regulating telomere length.
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Affiliation(s)
- Shyam Sushama Jose
- Cellular and Molecular Immunoregulation Group, Center for Translational Medicine, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czechia.,Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Federico Tidu
- Cellular and Molecular Immunoregulation Group, Center for Translational Medicine, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czechia.,Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Petra Burilova
- Cellular and Molecular Immunoregulation Group, Center for Translational Medicine, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czechia.,Department of Biology, Faculty of Medicine, Masaryk University, Brno, Czechia
| | - Tomas Kepak
- Pediatric Oncology Translational Research, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czechia.,Pediatric Hematology and Oncology, The University Hospital Brno, Brno, Czechia
| | - Kamila Bendickova
- Cellular and Molecular Immunoregulation Group, Center for Translational Medicine, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czechia
| | - Jan Fric
- Cellular and Molecular Immunoregulation Group, Center for Translational Medicine, International Clinical Research Center, St. Anne's University Hospital Brno, Brno, Czechia
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141
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Understanding the evolving phenotype of vascular complications in telomere biology disorders. Angiogenesis 2018; 22:95-102. [DOI: 10.1007/s10456-018-9640-7] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 08/06/2018] [Indexed: 12/23/2022]
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142
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Wang AS, Dreesen O. Biomarkers of Cellular Senescence and Skin Aging. Front Genet 2018; 9:247. [PMID: 30190724 PMCID: PMC6115505 DOI: 10.3389/fgene.2018.00247] [Citation(s) in RCA: 221] [Impact Index Per Article: 36.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Accepted: 06/22/2018] [Indexed: 02/06/2023] Open
Abstract
Cellular senescence is an irreversible growth arrest that occurs as a result of different damaging stimuli, including DNA damage, telomere shortening and dysfunction or oncogenic stress. Senescent cells exert a pleotropic effect on development, tissue aging and regeneration, inflammation, wound healing and tumor suppression. Strategies to remove senescent cells from aging tissues or preneoplastic lesions can delay tissue dysfunction and lead to increased healthspan. However, a significant hurdle in the aging field has been the identification of a universal biomarker that facilitates the unequivocal detection and quantification of senescent cell types in vitro and in vivo. Mammalian skin is the largest organ of the human body and consists of different cell types and compartments. Skin provides a physical barrier against harmful microbes, toxins, and protects us from ultraviolet radiation. Increasing evidence suggests that senescent cells accumulate in chronologically aged and photoaged skin; and may contribute to age-related skin changes and pathologies. Here, we highlight current biomarkers to detect senescent cells and review their utility in the context of skin aging. In particular, we discuss the efficacy of biomarkers to detect senescence within different skin compartments and cell types, and how they may contribute to myriad manifestations of skin aging and age-related skin pathologies.
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Affiliation(s)
- Audrey S Wang
- Cell Ageing, Skin Research Institute of Singapore (SRIS), A∗STAR, Singapore, Singapore
| | - Oliver Dreesen
- Cell Ageing, Skin Research Institute of Singapore (SRIS), A∗STAR, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
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143
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Fali T, Fabre-Mersseman V, Yamamoto T, Bayard C, Papagno L, Fastenackels S, Zoorab R, Koup RA, Boddaert J, Sauce D, Appay V. Elderly human hematopoietic progenitor cells express cellular senescence markers and are more susceptible to pyroptosis. JCI Insight 2018; 3:95319. [PMID: 29997288 DOI: 10.1172/jci.insight.95319] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 05/31/2018] [Indexed: 01/24/2023] Open
Abstract
The maintenance of effective immunity over time is dependent on the capacity of hematopoietic stem cells (HSCs) to sustain the pool of immunocompetent mature cells. Decline of immune competence with old age may stem from HSC defects, including reduced self-renewal potential and impaired lymphopoiesis, as suggested in murine models. To obtain further insights into aging-related alteration of hematopoiesis, we performed a comprehensive study of blood hematopoietic progenitor cells (HPCs) from older humans. In the elderly, HPCs present active oxidative phosphorylation and are pressed to enter cell cycling. However, p53-p21 and p15 cell senescence pathways, associated with telomerase activity deficiency, strong telomere attrition, and oxidative stress, are engaged, thus limiting cell cycling. Moreover, survival of old HPCs is impacted by pyroptosis, an inflammatory form of programmed cell death. Lastly, telomerase activity deficiency and telomere length attrition of old HPCs may be passed on to progeny cells such as naive T lymphocytes, further highlighting the poor hematopoietic potential of the elderly. This pre-senescent profile is characteristic of the multiple intrinsic and extrinsic factors affecting HPCs in elderly individuals and represents a major obstacle in terms of immune reconstitution and efficacy with advanced age.
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Affiliation(s)
- Tinhinane Fali
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Véronique Fabre-Mersseman
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Takuya Yamamoto
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA.,Laboratory of Immunosenescence, National Institutes of Biomedical Innovation, Health and Nutrition, Ibaraki-City, Osaka, Japan.,Center for AIDS Research, Kumamoto University, Kumamoto, Japan
| | - Charles Bayard
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Laura Papagno
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Solène Fastenackels
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Rima Zoorab
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Richard A Koup
- Immunology Laboratory, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, NIH, Bethesda, Maryland, USA
| | - Jacques Boddaert
- AP-HP, Hôpital Pitié-Salpêtrière, Service de Gériatrie, Paris, France
| | - Delphine Sauce
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France
| | - Victor Appay
- Sorbonne Université, INSERM, Centre d'Immunologie et des Maladies Infectieuses (CIMI-Paris), Paris, France.,International Research Center of Medical Sciences (IRCMS), Kumamoto University, Kumamoto, Japan
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144
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Tusup M, Kundig T, Pascolo S. Epitranscriptomics of cancer. World J Clin Oncol 2018; 9:42-55. [PMID: 29900123 PMCID: PMC5997933 DOI: 10.5306/wjco.v9.i3.42] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Revised: 04/18/2018] [Accepted: 05/23/2018] [Indexed: 02/06/2023] Open
Abstract
The functional impact of modifications of cellular RNAs, including mRNAs, miRNAs and lncRNAs, is a field of intense study. The role of such modifications in cancer has started to be elucidated. Diverse and sometimes opposite effects of RNA modifications have been reported. Some RNA modifications promote, while others decrease the growth and invasiveness of cancer. The present manuscript reviews the current knowledge on the potential impacts of N6-Methyladenosine, Pseudouridine, Inosine, 2’O-methylation or methylcytidine in cancer’s RNA. It also highlights the remaining questions and provides hints on research avenues and potential therapeutic applications, whereby modulating dynamic RNA modifications may be a new method to treat cancer.
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Affiliation(s)
- Marina Tusup
- Department of Dermatology, University Hospital of Zürich, Zurich 8091, Switzerland
- Faculty of Medicine, University of Zurich, Zurich 8091, Switzerland
| | - Thomas Kundig
- Department of Dermatology, University Hospital of Zürich, Zurich 8091, Switzerland
- Faculty of Medicine, University of Zurich, Zurich 8091, Switzerland
| | - Steve Pascolo
- Department of Dermatology, University Hospital of Zürich, Zurich 8091, Switzerland
- Faculty of Medicine, University of Zurich, Zurich 8091, Switzerland
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145
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HuR regulates telomerase activity through TERC methylation. Nat Commun 2018; 9:2213. [PMID: 29880812 PMCID: PMC5992219 DOI: 10.1038/s41467-018-04617-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2017] [Accepted: 05/07/2018] [Indexed: 01/21/2023] Open
Abstract
Telomerase consists of the catalytic protein TERT and the RNA TERC. Mutations in TERC are linked to human diseases, but the underlying mechanisms are poorly understood. Here we report that the RNA-binding protein HuR associates with TERC and promotes the assembly of the TERC/TERT complex by facilitating TERC C106 methylation. Dyskeratosis congenita (DC)-related TERC U100A mutation impair the association of HuR with TERC, thereby reducing C106 methylation. Two other TERC mutations linked to aplastic anemia and autosomal dominant DC, G107U, and GC107/108AG, likewise disrupt methylation at C106. Loss-of-HuR binding and hence lower TERC methylation leads to decreased telomerase activity and telomere shortening. Furthermore, HuR deficiency or mutation of mTERC HuR binding or methylation sites impair the renewal of mouse hematopoietic stem cells, recapitulating the bone marrow failure seen in DC. Collectively, our findings reveal a novel function of HuR, linking HuR to telomerase function and TERC-associated DC. Mutations in the RNA component TERC can cause telomerase dysfunction but the underlying mechanisms are largely unknown. Here, the authors show that RNA-binding protein HuR regulates telomerase function by enhancing the methylation of TERC, which is impaired by several disease-relevant TERC mutations.
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146
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Turning Uridines around: Role of rRNA Pseudouridylation in Ribosome Biogenesis and Ribosomal Function. Biomolecules 2018; 8:biom8020038. [PMID: 29874862 PMCID: PMC6023024 DOI: 10.3390/biom8020038] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 05/28/2018] [Accepted: 05/31/2018] [Indexed: 01/09/2023] Open
Abstract
Ribosomal RNA (rRNA) is extensively edited through base methylation and acetylation, 2'-O-ribose methylation and uridine isomerization. In human rRNA, 95 uridines are predicted to by modified to pseudouridine by ribonucleoprotein complexes sharing four core proteins and differing for a RNA sequence guiding the complex to specific residues to be modified. Most pseudouridylation sites are placed within functionally important ribosomal domains and can influence ribosomal functional features. Information obtained so far only partially explained the degree of regulation and the consequences of pseudouridylation on ribosomal structure and function in different physiological and pathological conditions. This short review focuses on the available evidence in this topic, highlighting open questions in the field and perspectives that the development of emerging techniques is offering.
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147
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148
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Abstract
Dyskeratosis congenita (DC) is a rare, inherited bone marrow failure (BMF) syndrome characterized by variable manifestations and ages of onset, and predisposition to cancer. DC is one of a spectrum of diseases caused by mutations in genes regulating telomere maintenance, collectively referred to as telomere biology disorders (TBDs). Hematologic disease is common in children with DC/TBD. Timely diagnosis of underlying TBD in patients with BMF affects treatment and has been facilitated by increased awareness and availability of diagnostic tests in recent years. This article summarizes the pathophysiology, evaluation, and management of hematopoietic failure in patients with DC and other TBDs.
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Affiliation(s)
- Suneet Agarwal
- Division of Hematology/Oncology, Harvard Medical School, Dana-Farber Boston Children's Cancer and Blood Disorders Center, Boston Children's Hospital, 1 Blackfan Circle, Karp 07214, Boston, MA 02115, USA.
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149
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An Activity Switch in Human Telomerase Based on RNA Conformation and Shaped by TCAB1. Cell 2018; 174:218-230.e13. [PMID: 29804836 DOI: 10.1016/j.cell.2018.04.039] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 03/22/2018] [Accepted: 04/27/2018] [Indexed: 12/24/2022]
Abstract
Ribonucleoprotein enzymes require dynamic conformations of their RNA constituents for regulated catalysis. Human telomerase employs a non-coding RNA (hTR) with a bipartite arrangement of domains-a template-containing core and a distal three-way junction (CR4/5) that stimulates catalysis through unknown means. Here, we show that telomerase activity unexpectedly depends upon the holoenzyme protein TCAB1, which in turn controls conformation of CR4/5. Cells lacking TCAB1 exhibit a marked reduction in telomerase catalysis without affecting enzyme assembly. Instead, TCAB1 inactivation causes unfolding of CR4/5 helices that are required for catalysis and for association with the telomerase reverse-transcriptase (TERT). CR4/5 mutations derived from patients with telomere biology disorders provoke defects in catalysis and TERT binding similar to TCAB1 inactivation. These findings reveal a conformational "activity switch" in human telomerase RNA controlling catalysis and TERT engagement. The identification of two discrete catalytic states for telomerase suggests an intramolecular means for controlling telomerase in cancers and progenitor cells.
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150
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Abstract
Studies of rare and common illnesses have led to remarkable progress in the understanding of the role of telomeres (nucleoprotein complexes at chromosome ends essential for chromosomal integrity) in human disease. Telomere biology disorders encompass a growing spectrum of conditions caused by rare pathogenic germline variants in genes encoding essential aspects of telomere function. Dyskeratosis congenita, a disorder at the severe end of this spectrum, typically presents in childhood with the classic triad of abnormal skin pigmentation, nail dystrophy, and oral leukoplakia, accompanied by a very high risk of bone marrow failure, cancer, pulmonary fibrosis, and other medical problems. In contrast, the less severe end of the telomere biology disorder spectrum consists of middle-age or older adults with just one feature typically seen in dyskeratosis congenita, such as pulmonary fibrosis or bone marrow failure. In the common disease realm, large-scale molecular epidemiology studies have discovered novel associations between illnesses, such as cancer, heart disease, and mental health, and both telomere length and common genetic variants in telomere biology genes. This review highlights recent findings of telomere biology in human disease from both the rare and common disease perspectives. Multi-disciplinary collaborations between clinicians, basic scientists, and epidemiologist are essential as we seek to incorporate new telomere biology discoveries to improve health outcomes.
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Affiliation(s)
- Sharon A. Savage
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland, USA
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