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Association of the Telomerase Reverse Transcriptase rs10069690 Polymorphism with the Risk, Age at Onset and Prognosis of Triple Negative Breast Cancer. Int J Mol Sci 2023; 24:ijms24031825. [PMID: 36768147 PMCID: PMC9916321 DOI: 10.3390/ijms24031825] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2022] [Revised: 01/04/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
Telomerase reverse transcriptase (TERT) plays a key role in the maintenance of telomere DNA length. The rs10069690 single nucleotide variant, located in intron 4 of TERT, was found to be associated with telomere length and the risk of estrogen receptor-negative but not-positive breast cancer. This study aimed at analysis of the association of rs10069690 genotype and TERT expression with the risk, age at onset, prognosis, and clinically and molecularly relevant subtypes of breast cancer. Accordingly, rs10069690 was genotyped in a hospital-based case-control study of 403 female breast cancer patients and 246 female controls of a Central European (Austrian) study population, and the mRNA levels of TERT were quantified in 106 primary breast tumors using qRT-PCR. We found that in triple-negative breast cancer patients, the minor rs10069690 TT genotype tended to be associated with an increased breast cancer risk (OR, 1.87; 95% CI, 0.75-4.71; p = 0.155) and was significantly associated with 11.7 years younger age at breast cancer onset (p = 0.0002), whereas the CC genotype was associated with a poor brain metastasis-free survival (p = 0.009). Overall, our data show that the rs10069690 CC genotype and a high TERT expression tended to be associated with each other and with a poor prognosis. Our findings indicate a key role of rs10069690 in triple-negative breast cancer.
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Yin H, Hardikar S, Lindstroem S, Hsu L, Anderson KE, Banbury BL, Berndt SI, Chan AT, Giovanucci EL, Harrison TA, Joshi AD, Nan H, Potter JD, Sakoda LC, Slattery ML, Schoen RE, White E, Peters U, Newcomb PA. Telomere Maintenance Variants and Survival after Colorectal Cancer: Smoking- and Sex-Specific Associations. Cancer Epidemiol Biomarkers Prev 2020; 29:1817-1824. [PMID: 32586834 PMCID: PMC7928192 DOI: 10.1158/1055-9965.epi-19-1507] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Revised: 02/14/2020] [Accepted: 06/22/2020] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Telomeres play an important role in colorectal cancer prognosis. Variation in telomere maintenance genes may be associated with survival after colorectal cancer diagnosis, but evidence is limited. In addition, possible interactions between telomere maintenance genes and prognostic factors, such as smoking and sex, also remain to be investigated. METHODS We conducted gene-wide analyses of colorectal cancer prognosis in 4,896 invasive colorectal cancer cases from the Genetics and Epidemiology of Colorectal Cancer Consortium (GECCO); 1,871 common variants within 13 telomere maintenance genes were included. Cox models were fit to estimate associations of these variants individually with overall and colorectal cancer-specific survival. Likelihood ratio tests were used to test for interaction by smoking and sex. P values were adjusted using Bonferroni correction. RESULTS The association between minor allele of rs7200950 (ACD) with colorectal cancer-specific survival varied significantly by smoking pack-years (corrected P = 0.049), but no significant trend was observed. By sex, minor alleles for rs2975843 (TERF1), rs75676021 (POT1), and rs74429678 (POT1) were associated with decreased overall and/or colorectal cancer-specific survival in women but not in men. CONCLUSIONS Our study reported a gene-wide statistically significant interaction with sex (TERF1, POT1). Although significant interaction by smoking pack-years (ACD) was observed, there was no evidence of a dose response. Validation of these findings in other large studies and further functional annotation on these SNPs are warranted. IMPACT Our study found a gene-smoking and gene-sex interaction on survival after colorectal cancer diagnosis, providing new insights into the role of genetic polymorphisms in telomere maintenance on colorectal cancer prognosis.
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Affiliation(s)
- Hang Yin
- Department of Epidemiology, University of Washington, Seattle, Washington
| | - Sheetal Hardikar
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
- Huntsman Cancer Institute, University of Utah, Salt Lake City, Utah
| | - Sara Lindstroem
- Department of Epidemiology, University of Washington, Seattle, Washington
| | - Li Hsu
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
- Department of Biostatistics, University of Washington, Seattle, Washington
| | - Kristin E Anderson
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota
| | - Barbara L Banbury
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Sonja I Berndt
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, NIH, Bethesda, Maryland
| | - Andrew T Chan
- Division of Gastroenterology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
- Clinical and Translational Epidemiology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
- Broad Institute of Harvard and MIT, Cambridge, Massachusetts
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Edward L Giovanucci
- Channing Division of Network Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts
- Departments of Epidemiology and Nutrition, Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Tabitha A Harrison
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Amit D Joshi
- Clinical and Translational Epidemiology Unit, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts
- Department of Epidemiology, Harvard T.H. Chan School of Public Health, Harvard University, Boston, Massachusetts
| | - Hongmei Nan
- Department of Epidemiology, Richard M. Fairbanks School of Public Health, Indiana University, Indianapolis, Indiana
- Melvin and Bren Simon Cancer Center, Indiana University, Indianapolis, Indiana
| | - John D Potter
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Lori C Sakoda
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
- Division of Research, Kaiser Permanente Northern California, Oakland, California
| | - Martha L Slattery
- Department of Internal Medicine, University of Utah, Salt Lake City, Utah
| | - Robert E Schoen
- Department of Medicine and Epidemiology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - Emily White
- Department of Epidemiology, University of Washington, Seattle, Washington
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Ulrike Peters
- Department of Epidemiology, University of Washington, Seattle, Washington
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
| | - Polly A Newcomb
- Department of Epidemiology, University of Washington, Seattle, Washington.
- Public Health Sciences Division, Fred Hutchinson Cancer Research Center, Seattle, Washington
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Eaaswarkhanth M, dos Santos ALC, Gokcumen O, Al-Mulla F, Thanaraj TA. Genome-Wide Selection Scan in an Arabian Peninsula Population Identifies a TNKS Haplotype Linked to Metabolic Traits and Hypertension. Genome Biol Evol 2020; 12:77-87. [PMID: 32068798 PMCID: PMC7093833 DOI: 10.1093/gbe/evaa033] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/13/2020] [Indexed: 12/12/2022] Open
Abstract
Despite the extreme and varying environmental conditions prevalent in the Arabian Peninsula, it has experienced several waves of human migrations following the out-of-Africa diaspora. Eventually, the inhabitants of the peninsula region adapted to the hot and dry environment. The adaptation and natural selection that shaped the extant human populations of the Arabian Peninsula region have been scarcely studied. In an attempt to explore natural selection in the region, we analyzed 662,750 variants in 583 Kuwaiti individuals. We searched for regions in the genome that display signatures of positive selection in the Kuwaiti population using an integrative approach in a conservative manner. We highlight a haplotype overlapping TNKS that showed strong signals of positive selection based on the results of the multiple selection tests conducted (integrated Haplotype Score, Cross Population Extended Haplotype Homozygosity, Population Branch Statistics, and log-likelihood ratio scores). Notably, the TNKS haplotype under selection potentially conferred a fitness advantage to the Kuwaiti ancestors for surviving in the harsh environment while posing a major health risk to present-day Kuwaitis.
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Affiliation(s)
| | - Andre Luiz Campelo dos Santos
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo
- Department of Archeology, Federal University of Pernambuco, Recife, Brazil
| | - Omer Gokcumen
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo
| | - Fahd Al-Mulla
- Department of Genetics and Bioinformatics, Dasman Diabetes Institute, Kuwait City, Kuwait
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Anitha A, Thanseem I, Vasu MM, Viswambharan V, Poovathinal SA. Telomeres in neurological disorders. Adv Clin Chem 2019; 90:81-132. [PMID: 31122612 DOI: 10.1016/bs.acc.2019.01.003] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Ever since their discovery, the telomeres and the telomerase have been topics of intensive research, first as a mechanism of cellular aging and later as an indicator of health and diseases in humans. By protecting the chromosome ends, the telomeres play a vital role in preserving the information in our genome. Telomeres shorten with age and the rate of telomere erosion provides insight into the proliferation history of cells. The pace of telomere attrition is known to increase at the onset of several pathological conditions. Telomere shortening has been emerging as a potential contributor in the pathogenesis of several neurological disorders including autism spectrum disorders (ASD), schizophrenia, Alzheimer's disease (AD), Parkinson's disease (PD) and depression. The rate of telomere attrition in the brain is slower than that of other tissues owing to the low rate of cell proliferation in brain. Telomere maintenance is crucial for the functioning of stem cells in brain. Taking together the studies on telomere attrition in various neurological disorders, an association between telomere shortening and disease status has been demonstrated in schizophrenia, AD and depression, in spite of a few negative reports. But, studies in ASD and PD have failed to produce conclusive results. The cause-effect relationship between TL and neurological disorders is yet to be elucidated. The factors responsible for telomere erosion, which have also been implicated in the pathogenesis of neurological disorders, need to be explored in detail. Telomerase activation is now being considered as a potential therapeutic strategy for neurological disorders.
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Affiliation(s)
- Ayyappan Anitha
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India.
| | - Ismail Thanseem
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Mahesh Mundalil Vasu
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Vijitha Viswambharan
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
| | - Suresh A Poovathinal
- Institute for Communicative and Cognitive Neurosciences (ICCONS), Palakkad, Kerala, India
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The Guardian of the Genome Revisited: p53 Downregulates Genes Required for Telomere Maintenance, DNA Repair, and Centromere Structure. Cancers (Basel) 2018; 10:cancers10050135. [PMID: 29734785 PMCID: PMC5977108 DOI: 10.3390/cancers10050135] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 04/30/2018] [Accepted: 05/02/2018] [Indexed: 02/06/2023] Open
Abstract
The p53 protein has been extensively studied for its capacity to prevent proliferation of cells with a damaged genome. Surprisingly, however, our recent analysis of mice expressing a hyperactive mutant p53 that lacks the C-terminal domain revealed that increased p53 activity may alter genome maintenance. We showed that p53 downregulates genes essential for telomere metabolism, DNA repair, and centromere structure and that a sustained p53 activity leads to phenotypic traits associated with dyskeratosis congenita and Fanconi anemia. This downregulation is largely conserved in human cells, which suggests that our findings could be relevant to better understand processes involved in bone marrow failure as well as aging and tumor suppression.
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Du H, Guo Y, Ma D, Tang K, Cai D, Luo Y, Xie C. A case report of heterozygous TINF2 gene mutation associated with pulmonary fibrosis in a patient with dyskeratosis congenita. Medicine (Baltimore) 2018; 97:e0724. [PMID: 29742735 PMCID: PMC5959423 DOI: 10.1097/md.0000000000010724] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
RATIONALE Dyskeratosis congenita (DC) is a rare inherited disease characterized by the classical mucocutaneous triad. Pulmonary fibrosis, bone marrow failure, and solid tumors are the main causes of mortality in DC. Pathogenic variants in TERT, TERC, and DKC1 have been identified in individuals with familial pulmonary fibrosis. Mutations in TINF2 gene have been reported to be associated with bone marrow failure in most cases. However, the relationship between TINF2 mutation and pulmonary fibrosis is not yet clear. PATIENT CONCERNS Here, we report the case of a 32-year-old woman presented with irritating cough for 2 years and progressive breathlessness for 6 months. DIAGNOSES The patient was diagnosed with DC based on the following clinical evidences. Along with some family members, she had the typical mucocutaneous triad and pulmonary fibrosis. A heterozygous mutation (c.844C>T), located in exon 6 of TINF2 gene, that changed arginine to cysteine (Arg282Cys) was identified in this proband by whole exome sequencing. INTERVENTIONS The patient received corticosteroid therapy but refused to receive lung transplantation. OUTCOMES The proband died of respiratory failure 4 months after the diagnosis. The missense mutation was located in the conserved region of TINF2 gene and predicted to be deleterious by altering the protein structure. LESSONS Lung transplantation should be considered for improved survival of patients with DC, and pulmonary fibrosis. Whole exome and whole genome sequencing should be widely used in the identification of such rare genetic variants for clinical diagnosis. The study of DC with pulmonary fibrosis can provide a more appropriate means of clinical research and therapy to the unfortunate patients who suffer from this rare disorder.
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Affiliation(s)
- Hongchun Du
- Department of Respiratory Medicine, The First Affiliated Hospital, Sun Yat-sen University
| | - Yubiao Guo
- Department of Respiratory Medicine, The First Affiliated Hospital, Sun Yat-sen University
| | - Di Ma
- Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Kejing Tang
- Department of Respiratory Medicine, The First Affiliated Hospital, Sun Yat-sen University
| | - Decheng Cai
- Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, China
| | - Yifeng Luo
- Department of Respiratory Medicine, The First Affiliated Hospital, Sun Yat-sen University
| | - Canmao Xie
- Department of Respiratory Medicine, The First Affiliated Hospital, Sun Yat-sen University
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Sack MN, Fyhrquist FY, Saijonmaa OJ, Fuster V, Kovacic JC. Basic Biology of Oxidative Stress and the Cardiovascular System: Part 1 of a 3-Part Series. J Am Coll Cardiol 2017; 70:196-211. [PMID: 28683968 DOI: 10.1016/j.jacc.2017.05.034] [Citation(s) in RCA: 144] [Impact Index Per Article: 20.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 04/24/2017] [Accepted: 05/10/2017] [Indexed: 01/18/2023]
Abstract
The generation of reactive oxygen species (ROS) is a fundamental aspect of normal human biology. However, when ROS generation exceeds endogenous antioxidant capacity, oxidative stress arises. If unchecked, ROS production and oxidative stress mediate tissue and cell damage that can spiral in a cycle of inflammation and more oxidative stress. This article is part 1 of a 3-part series covering the role of oxidative stress in cardiovascular disease. The broad theme of this first paper is the mechanisms and biology of oxidative stress. Specifically, the authors review the basic biology of oxidative stress, relevant aspects of mitochondrial function, and stress-related cell death pathways (apoptosis and necrosis) as they relate to the heart and cardiovascular system. They then explore telomere biology and cell senescence. As important regulators and sensors of oxidative stress, telomeres are segments of repetitive nucleotide sequence at each end of a chromosome that protect the chromosome ends from deterioration.
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Affiliation(s)
- Michael N Sack
- Cardiovascular and Pulmonary Branch, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, Maryland.
| | | | | | - Valentin Fuster
- Zena and Michael A. Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, New York; Marie-Josée and Henry R. Kravis Cardiovascular Health Center, Icahn School of Medicine at Mount Sinai, New York, New York; Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid, Spain
| | - Jason C Kovacic
- Zena and Michael A. Wiener Cardiovascular Institute, Icahn School of Medicine at Mount Sinai, New York, New York.
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Kachuri L, Latifovic L, Liu G, Hung RJ. Systematic Review of Genetic Variation in Chromosome 5p15.33 and Telomere Length as Predictive and Prognostic Biomarkers for Lung Cancer. Cancer Epidemiol Biomarkers Prev 2016; 25:1537-1549. [PMID: 27566420 DOI: 10.1158/1055-9965.epi-16-0200] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 07/20/2016] [Accepted: 08/17/2016] [Indexed: 11/16/2022] Open
Abstract
Lung cancer remains the leading cause of cancer mortality worldwide. Known histomolecular characteristics and genomic profiles provide limited insight into factors influencing patient outcomes. Telomere length (TL) is important for genomic integrity and has been a growing area of interest as agents targeting telomerase are being evaluated. Chromosome 5p15.33, an established cancer susceptibility locus, contains a telomerase-regulatory gene, TERT, and CLPTM1L, a gene associated with cisplatin-induced apoptosis. This review offers a summary of the clinical utility of 5p15.33 polymorphisms and TL. A total of 621 abstracts were screened, and 14 studies (7 for 5p15.33, 7 for TL) were reviewed. Endpoints included overall survival (OS), progression-free survival (PFS), therapy response, and toxicity. Of the 23 genetic variants identified, significant associations with OS and/or PFS were reported for rs401681 (CLPTM1L), rs4975616 (TERT-CLPTM1L), and rs2736109 (TERT). Both shorter and longer TL, in tumor and blood, was linked to OS and PFS. Overall, consistent evidence across multiple studies of 5p15.33 polymorphisms and TL was lacking. Despite the potential to become useful prognostic biomarkers in lung cancer, the limited number of reports and their methodologic limitations highlight the need for larger, carefully designed studies with clinically defined subpopulations and higher resolution genetic analyses. Cancer Epidemiol Biomarkers Prev; 25(12); 1537-49. ©2016 AACR.
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Affiliation(s)
- Linda Kachuri
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada.,Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.,Prevention & Cancer Control, Cancer Care Ontario, Toronto, Ontario, Canada
| | - Lidija Latifovic
- Prevention & Cancer Control, Cancer Care Ontario, Toronto, Ontario, Canada
| | - Geoffrey Liu
- Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada.,Ontario Cancer Institute, Princess Margaret Cancer Center, Toronto, Ontario, Canada.,Department of Medical Biophysics, University of Toronto, Toronto, Ontario, Canada
| | - Rayjean J Hung
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada. .,Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario, Canada
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Modifiable Factors Influencing Telomere Length and Aging. INFLAMMATION, AGING, AND OXIDATIVE STRESS 2016. [DOI: 10.1007/978-3-319-33486-8_4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Kachuri L, Amos CI, McKay JD, Johansson M, Vineis P, Bueno-de-Mesquita H, Boutron-Ruault MC, Johansson M, Quirós J, Sieri S, Travis RC, Weiderpass E, Le Marchand L, Henderson BE, Wilkens L, Goodman GE, Chen C, Doherty JA, Christiani DC, Wei Y, Su L, Tworoger S, Zhang X, Kraft P, Zaridze D, Field JK, Marcus MW, Davies MP, Hyde R, Caporaso NE, Landi MT, Severi G, Giles GG, Liu G, McLaughlin JR, Li Y, Xiao X, Fehringer G, Zong X, Denroche RE, Zuzarte PC, McPherson JD, Brennan P, Hung RJ. Fine mapping of chromosome 5p15.33 based on a targeted deep sequencing and high density genotyping identifies novel lung cancer susceptibility loci. Carcinogenesis 2016; 37:96-105. [PMID: 26590902 PMCID: PMC4715236 DOI: 10.1093/carcin/bgv165] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Revised: 11/02/2015] [Accepted: 11/13/2015] [Indexed: 01/01/2023] Open
Abstract
Chromosome 5p15.33 has been identified as a lung cancer susceptibility locus, however the underlying causal mechanisms were not fully elucidated. Previous fine-mapping studies of this locus have relied on imputation or investigated a small number of known, common variants. This study represents a significant advance over previous research by investigating a large number of novel, rare variants, as well as their underlying mechanisms through telomere length. Variants for this fine-mapping study were identified through a targeted deep sequencing (average depth of coverage greater than 4000×) of 576 individuals. Subsequently, 4652 SNPs, including 1108 novel SNPs, were genotyped in 5164 cases and 5716 controls of European ancestry. After adjusting for known risk loci, rs2736100 and rs401681, we identified a new, independent lung cancer susceptibility variant in LPCAT1: rs139852726 (OR = 0.46, P = 4.73×10(-9)), and three new adenocarcinoma risk variants in TERT: rs61748181 (OR = 0.53, P = 2.64×10(-6)), rs112290073 (OR = 1.85, P = 1.27×10(-5)), rs138895564 (OR = 2.16, P = 2.06×10(-5); among young cases, OR = 3.77, P = 8.41×10(-4)). In addition, we found that rs139852726 (P = 1.44×10(-3)) was associated with telomere length in a sample of 922 healthy individuals. The gene-based SKAT-O analysis implicated TERT as the most relevant gene in the 5p15.33 region for adenocarcinoma (P = 7.84×10(-7)) and lung cancer (P = 2.37×10(-5)) risk. In this largest fine-mapping study to investigate a large number of rare and novel variants within 5p15.33, we identified novel lung and adenocarcinoma susceptibility loci with large effects and provided support for the role of telomere length as the potential underlying mechanism.
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Affiliation(s)
- Linda Kachuri
- Lunenfeld-Tanenbaum Research Institute of Mount Sinai Hospital, Toronto, Ontario M5T 3L9, Canada
- Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario M5T 3M7, Canada
| | - Christopher I. Amos
- Department of Community and Family Medicine, Center for Genomic Medicine, Geisel School of Medicine, Dartmouth College, Lebanon, NH 03766, USA
| | - James D. McKay
- International Agency for Research on Cancer, Lyon, CEDEX 08, 69372, France
| | - Mattias Johansson
- International Agency for Research on Cancer, Lyon, CEDEX 08, 69372, France
| | - Paolo Vineis
- Human Genetics Foundation (HuGeF), 10126Torino, Italy
- Department of Epidemiology and Biostatistics, MRC-PHE Centre for Environment and Health, School of Public Health, Imperial College London, Norfolk Place, London W2 1PG, UK
| | - H.Bas Bueno-de-Mesquita
- Department for Determinants of Chronic Diseases (DCD), National Institute for Public Health and the Environment (RIVM), 3721 MA Bilthoven, The Netherlands
- Department of Gastroenterology and Hepatology, University Medical Centre, 3584 CX Utrecht, The Netherlands
- Department of Epidemiology and Biostatistics, The School of Public Health, Imperial College London, London SW7 2AZ, UK
- Department of Social and Preventive Medicine, Faculty of Medicine, University of Malaya, Kuala Lumpur 50603, Malaysia
| | - Marie-Christine Boutron-Ruault
- INSERM, Centre for Research in Epidemiology and Population Health (CESP), U1018, Lifestyle, Genes and Health: Integrative Trans-Generational Epidemiology, 94805 Villejuif, France
- Université Paris Sud, UMRS 1018 94805, Villejuif, France
- Institut Gustave RoussyF-94805, Villejuif, France
| | - Mikael Johansson
- Department of Radiation Sciences, Umeå University, Umeå SE-901 87, Sweden
| | - J.Ramón Quirós
- Public Health Directorate Asturias, CP 33006 Oviedo, Spain
| | - Sabina Sieri
- Epidemiology and Prevention Unit, Fondazione IRCCS Istituto Nazionale dei Tumori, 20133 Milano, Italy
| | - Ruth C. Travis
- Cancer Epidemiology Unit, Nuffield Department of Population Health, University of Oxford, Oxford OX3 7LF, UK
| | - Elisabete Weiderpass
- Department of Community Medicine, Faculty of Health Sciences, University of Tromsø, The Arctic University of Norway, 9037 Tromsø, Norway
- Department of Research, Cancer Registry of Norway, 0379 Oslo, Norway
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm SE-171 77, Sweden
- Genetic Epidemiology Group, Folkhälsan Research Center, Helsinki FI-00014, Finland
| | | | | | - Lynne Wilkens
- University of Hawaii Cancer Center, Honolulu, HI 96813, USA
| | - Gary E. Goodman
- Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Chu Chen
- Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA
| | - Jennifer A. Doherty
- Department of Community and Family Medicine, Center for Genomic Medicine, Geisel School of Medicine, Dartmouth College, Lebanon, NH 03766, USA
| | - David C. Christiani
- Departments of Environmental Health and Epidemiology, Harvard School of Public Health, Boston, MA 02115, USA
- Department of Medicine, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
| | - Yongyue Wei
- Departments of Environmental Health and Epidemiology, Harvard School of Public Health, Boston, MA 02115, USA
| | - Li Su
- Departments of Environmental Health and Epidemiology, Harvard School of Public Health, Boston, MA 02115, USA
| | - Shelley Tworoger
- Departments of Environmental Health and Epidemiology, Harvard School of Public Health, Boston, MA 02115, USA
- Channing Division of Network Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Xuehong Zhang
- Channing Division of Network Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA 02115, USA
| | - Peter Kraft
- Departments of Biostatistics and Epidemiology, Harvard School of Public Health, Boston, MA 02115, USA
| | - David Zaridze
- Russian Cancer Research Center, Moscow 115478, Russia
| | - John K. Field
- Roy Castle Lung Cancer Research Programme, University of Liverpool Cancer Research Centre Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| | - Michael W. Marcus
- Roy Castle Lung Cancer Research Programme, University of Liverpool Cancer Research Centre Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| | - Michael P.A. Davies
- Roy Castle Lung Cancer Research Programme, University of Liverpool Cancer Research Centre Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| | - Russell Hyde
- Roy Castle Lung Cancer Research Programme, University of Liverpool Cancer Research Centre Institute of Translational Medicine, University of Liverpool, Liverpool L69 3BX, UK
| | - Neil E. Caporaso
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA
| | - Maria Teresa Landi
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA
| | - Gianluca Severi
- Human Genetics Foundation (HuGeF), 10126Torino, Italy
- INSERM, Centre for Research in Epidemiology and Population Health (CESP), U1018, Lifestyle, Genes and Health: Integrative Trans-Generational Epidemiology, 94805 Villejuif, France
- Université Paris Sud, UMRS 1018 94805, Villejuif, France
- Institut Gustave RoussyF-94805, Villejuif, France
- Cancer Epidemiology Centre, Cancer Council Victoria, Melbourne 3004, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne 3010, Australia
| | - Graham G. Giles
- Cancer Epidemiology Centre, Cancer Council Victoria, Melbourne 3004, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, University of Melbourne, Melbourne 3010, Australia
- Department of Epidemiology and Preventive Medicine, Monash University, Melbourne 3004, Australia
| | - Geoffrey Liu
- Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario M5T 3M7, Canada
- Ontario Cancer Institute, Princess Margaret Cancer Center, Toronto, Ontario M5G 0A3, Canada
| | - John R. McLaughlin
- Lunenfeld-Tanenbaum Research Institute of Mount Sinai Hospital, Toronto, Ontario M5T 3L9, Canada
- Public Health Ontario, Toronto, Ontario M5G 1V2, Canada, and
| | - Yafang Li
- Department of Community and Family Medicine, Center for Genomic Medicine, Geisel School of Medicine, Dartmouth College, Lebanon, NH 03766, USA
| | - Xiangjun Xiao
- Department of Community and Family Medicine, Center for Genomic Medicine, Geisel School of Medicine, Dartmouth College, Lebanon, NH 03766, USA
| | - Gord Fehringer
- Lunenfeld-Tanenbaum Research Institute of Mount Sinai Hospital, Toronto, Ontario M5T 3L9, Canada
| | - Xuchen Zong
- Lunenfeld-Tanenbaum Research Institute of Mount Sinai Hospital, Toronto, Ontario M5T 3L9, Canada
| | - Robert E. Denroche
- Genome Technologies, Ontario Institute for Cancer Research, Toronto, Ontario M5G 0A3, Canada
| | - Philip C. Zuzarte
- Genome Technologies, Ontario Institute for Cancer Research, Toronto, Ontario M5G 0A3, Canada
| | - John D. McPherson
- Genome Technologies, Ontario Institute for Cancer Research, Toronto, Ontario M5G 0A3, Canada
| | - Paul Brennan
- International Agency for Research on Cancer, Lyon, CEDEX 08, 69372, France
| | - Rayjean J. Hung
- Lunenfeld-Tanenbaum Research Institute of Mount Sinai Hospital, Toronto, Ontario M5T 3L9, Canada
- Division of Epidemiology, Dalla Lana School of Public Health, University of Toronto, Toronto, Ontario M5T 3M7, Canada
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11
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Mirabello L, Chung CC, Yeager M, Savage SA. Characterization of population-based variation and putative functional elements for the multiple-cancer susceptibility loci at 5p15.33. F1000Res 2014; 3:231. [PMID: 26664699 PMCID: PMC4654438 DOI: 10.12688/f1000research.5186.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/15/2014] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND TERT encodes the telomerase reverse transcriptase, which is responsible for maintaining telomere ends by addition of (TTAGGG) n nucleotide repeats at the telomere. Recent genome-wide association studies have found common genetic variants at the TERT-CLPTM1L locus (5p15.33) associated with an increased risk of several cancers. RESULTS Data were acquired for 1627 variants in 1092 unrelated individuals from 14 populations within the 1000 Genomes Project. We assessed the population genetics of the 5p15.33 region, including recombination hotspots, diversity, heterozygosity, differentiation among populations, and potential functional impacts. There were significantly lower polymorphism rates, divergence, and heterozygosity for the coding variants, particularly for non-synonymous sites, compared with non-coding and silent changes. Many of the cancer-associated SNPs had differing genotype frequencies among ancestral groups and were associated with potential regulatory changes. CONCLUSIONS Surrogate SNPs in linkage disequilibrium with the majority of cancer-associated SNPs were functional variants with a likely role in regulation of TERT and/or CLPTM1L. Our findings highlight several SNPs that future studies should prioritize for evaluation of functional consequences.
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Affiliation(s)
- Lisa Mirabello
- Division of Cancer Epidemiology and Genetics, National Cancer Institute,National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA
| | - Charles C. Chung
- Division of Cancer Epidemiology and Genetics, National Cancer Institute,National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA
| | - Meredith Yeager
- Cancer Genomics Research Laboratory, National Cancer Institute, Division of Cancer Epidemiology and Genetics, Leidos Biomedical Research, Inc., Frederick, MD 20877, USA
| | - Sharon A Savage
- Division of Cancer Epidemiology and Genetics, National Cancer Institute,National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA
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12
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Jung SW, Park NH, Shin JW, Park BR, Kim CJ, Lee JE, Shin ES, Kim JA, Chung YH. Prognostic impact of telomere maintenance gene polymorphisms on hepatocellular carcinoma patients with chronic hepatitis B. Hepatology 2014; 59:1912-20. [PMID: 23907815 DOI: 10.1002/hep.26655] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/03/2013] [Accepted: 07/19/2013] [Indexed: 01/01/2023]
Abstract
UNLABELLED Our goal was to determine whether single-nucleotide polymorphisms (SNPs) of telomere maintenance genes influence the development and clinical outcomes of patients with hepatitis B virus (HBV)-associated hepatocellular carcinoma (HCC). We evaluated 20 SNPs of five telomere maintenance genes in 702 patients with HCC and 351 hepatitis B virus surface antigen-positive controls without HCC. Significant SNPs were then validated in an independent cohort of 857 HCC patients and 429 controls. We assessed the association of each SNP with the development of HCC and overall survival through a multivariate Cox proportional analysis. A significantly increased risk of HCC development was identified for the telomerase-associated protein 1 (TEP1) rs1713449 SNP in both the discovery and replication phases (combined odds ratio = 1.42, P = 9.378 × 10(-5) ). In addition, the TEP1 rs1713449, TEP1 rs872072, protection of telomeres 1 homolog rs7784168, telomerase reverse transcriptase rs13167280, and telomeric repeat binding factor 1 rs2306494 SNPs had a significant effect on the overall survival, and a similar survival effect was validated in the replication cohort. Moreover, there was a significant dose-dependent association between the number of putatively high-risk genotypes of the five aforementioned SNPs and overall survival. The median survival time was significantly prolonged for patients with HCC with two or fewer putatively high-risk genotypes versus those with three or more high-risk genotypes (85 versus 44 months, log-rank P = 4.483 × 10(-5) ), and this was demonstrated in the replication cohort (52 versus 37 months, log-rank P = 0.026). CONCLUSION These observations suggest that the SNPs of telomere maintenance genes play a potential role in the development of HCC and the survival of HCC patients with chronic HBV infections.
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Affiliation(s)
- Seok Won Jung
- Department of Internal Medicine, University of Ulsan College of Medicine, Ulsan University Hospital, Ulsan, Korea
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13
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Marrone A, Dokal I. Dyskeratosis congenita: a disorder of telomerase deficiency and its relationship to other diseases. ACTA ACUST UNITED AC 2014. [DOI: 10.1586/17469872.1.3.463] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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14
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Hough J, Williamson RJ, Wright SI. Patterns of Selection in Plant Genomes. ANNUAL REVIEW OF ECOLOGY EVOLUTION AND SYSTEMATICS 2013. [DOI: 10.1146/annurev-ecolsys-110512-135851] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Plants show a wide range of variation in mating system, ploidy level, and demographic history, allowing for unique opportunities to investigate the evolutionary and genetic factors affecting genome-wide patterns of positive and negative selection. In this review, we highlight recent progress in our understanding of the extent and nature of selection on plant genomes. We discuss differences in selection as they relate to variation in demography, recombination, mating system, and ploidy. We focus on the population genetic consequences of these factors and argue that, although variation in the magnitude of purifying selection is well documented, quantifying rates of positive selection and disentangling the relative importance of recombination, demography, and ploidy are ongoing challenges. Large-scale comparative studies that examine the relative and joint importance of these processes, combined with explicit models of population history and selection, are key and feasible goals for future work.
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Affiliation(s)
- Josh Hough
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada, M5S 3B2;, ,
| | - Robert J. Williamson
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada, M5S 3B2;, ,
| | - Stephen I. Wright
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, Ontario, Canada, M5S 3B2;, ,
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15
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Zhang X, Lin S, Funk WE, Hou L. Republished: Environmental and occupational exposure to chemicals and telomere length in human studies. Postgrad Med J 2013; 89:722-8. [DOI: 10.1136/postgradmedj-2012-101350rep] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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16
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Zhang X, Lin S, Funk WE, Hou L. Environmental and occupational exposure to chemicals and telomere length in human studies. Occup Environ Med 2013; 70:743-9. [PMID: 23775864 DOI: 10.1136/oemed-2012-101350] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Telomeres are complexes of tandem repeats of DNA (5'-TTAGGG-3') and protein that cap eukaryotic chromosomes and play a critical role in chromosome stability. Telomeres shorten with aging and this process can be accelerated by increased oxidative stress and episodes of inflammation. Evidence is rapidly growing that telomere length (TL) may be affected by environmental chemicals that have frequently been associated with chronic diseases. In this article, we review the published data on TL in relation to environmental and occupational exposure to several chemicals based on our own and others' studies. The environmental and occupational exposures associated with shorter TL include traffic-related air pollution (ie, particulate matter (PM), black carbon (BC), and benzene and toluene), polycyclic aromatic hydrocarbons (PAHs), N-nitrosamines, pesticides, lead, exposure in car mechanical workshops, and hazardous waste exposure. Arsenic, persistent organic pollutants (POPs) and short-term exposure to PM are associated with longer TL. We discuss the possible reasons for the differences in results, including time- and dose-related issues, study design, and possible mechanisms involved in telomere regulation. We also discuss the future directions and challenges for TL-related environmental and occupational health research, such as investigation of TL in subpopulations of blood leukocytes, and the study of genetic and epigenetic factors that may regulate telomere integrity using longitudinal designs.
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Affiliation(s)
- Xiao Zhang
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, Illinois, USA
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17
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18
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Chen P, Zou P, Yan Q, Xu H, Zhao P, Gu A. The TERT MNS16A polymorphism contributes to cancer susceptibility: meta-analysis of the current studies. Gene 2013; 519:266-70. [PMID: 23462332 DOI: 10.1016/j.gene.2013.02.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2012] [Revised: 01/16/2013] [Accepted: 02/07/2013] [Indexed: 11/30/2022]
Abstract
The MNS16A polymorphism in the telomerase reverse transcriptase (TERT) gene has been implicated in cancer risk in multiple populations and various types of cancers; however, the results of previous studies exploring this association were inconclusive. To more precisely evaluate the relationship between the TERT MNS16A polymorphism and cancer risk, we performed a meta-analysis based on 8 studies described in 7 articles comprising 7864 controls and 4355 cases. The summary odds ratios (ORs) and their corresponding 95% confidence intervals (CIs) were estimated to assess the strength of the association in a fixed-effects model or a random-effects model where appropriate. Heterogeneity among articles and their publication bias were also tested. Overall, the pooled results indicated that the MNS16A polymorphism was significantly associated with increased cancer risk in the homozygote comparison model (SS vs. LL: OR=1.280, 95% CI 1.060-1.547) and the recessive model (SS vs. LL+SL: OR=1.201, 95% CI 1.004-1.436). In the stratified analyses, a statistically significant association was observed among Caucasians and in population-based studies. We also performed the analyses by cancer type, and a significantly increased risk of glioma was found in four genetic models. Our results suggest that the TERT MNS16A polymorphism most likely contributes to an increased risk of cancer. Moreover, the same relationship was found when the studies were stratified by cancer type, ethnicity and source of controls.
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Affiliation(s)
- Pin Chen
- Department of Neurosurgery, The First Affiliated Hospital of Nanjing Medical University, 300 Guangzhou Road, Nanjing, 210029, China
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19
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Yanowsky K, Barroso A, Osorio A, Urioste M, Benitez J, Martinez-Delgado B. Mutational analysis of telomere genes in BRCA1/2-negative breast cancer families with very short telomeres. Breast Cancer Res Treat 2012; 134:1337-43. [PMID: 22752289 DOI: 10.1007/s10549-012-2141-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Accepted: 06/12/2012] [Indexed: 11/26/2022]
Abstract
A majority of the familial breast cancer cases are not explained by mutations in the best-known high susceptibility genes BRCA1 and BRCA2. Since there is a link between DNA repair and telomere maintenance mechanisms, we have investigated for the first time the role of telomere genes in breast cancer predisposition. By a combination of DHPLC and direct sequencing, we screened for sequence variation in 14 telomere-related genes which included telomerase and shelterin complexes in index cases from 50 BRCA1/2-negative families previously characterized to have very short telomere length in peripheral blood leukocytes. Clear pathogenic changes were not detected in any of the genes analyzed. Most of the changes were non-coding variants and only nine corresponded to coding variants located in TPP1, TINF2, NHP2, TNKS, and RAD54B genes; although only two corresponded to coding missense changes leading to aminoacid changes in genes NHP2 and RAD54B. However, functional prediction analysis and control population studies of both variants ruled out its possible pathogenic role. Our results discard a major contribution of telomere-specific genes in hereditary breast cancer.
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Affiliation(s)
- Kira Yanowsky
- Human Genetics Group, Spanish National Cancer Research Centre (CNIO), Melchor Fernandez Almagro 3, 28029 Madrid, Spain
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20
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Mirabello L, Yeager M, Chowdhury S, Qi L, Deng X, Wang Z, Hutchinson A, Savage SA. Worldwide genetic structure in 37 genes important in telomere biology. Heredity (Edinb) 2012; 108:124-33. [PMID: 21731055 PMCID: PMC3193882 DOI: 10.1038/hdy.2011.55] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2011] [Revised: 05/10/2011] [Accepted: 05/31/2011] [Indexed: 01/02/2023] Open
Abstract
Telomeres form the ends of eukaryotic chromosomes and are vital in maintaining genetic integrity. Telomere dysfunction is associated with cancer and several chronic diseases. Patterns of genetic variation across individuals can provide keys to further understanding the evolutionary history of genes. We investigated patterns of differentiation and population structure of 37 telomere maintenance genes among 53 worldwide populations. Data from 898 unrelated individuals were obtained from the genome-wide scan of the Human Genome Diversity Panel (HGDP) and from 270 unrelated individuals from the International HapMap Project at 716 single-nucleotide polymorphism (SNP) loci. We additionally compared this gene set to HGDP data at 1396 SNPs in 174 innate immunity genes. The majority of the telomere biology genes had low to moderate haplotype diversity (45-85%), high ancestral allele frequencies (>60%) and low differentiation (FST<0.10). Heterozygosity and differentiation were significantly lower in telomere biology genes compared with the innate immunity genes. There was evidence of evolutionary selection in ACD, TERF2IP, NOLA2, POT1 and TNKS in this data set, which was consistent in HapMap 3. TERT had higher than expected levels of haplotype diversity, likely attributable to a lack of linkage disequilibrium, and a potential cancer-associated SNP in this gene, rs2736100, varied substantially in genotype frequency across major continental regions. It is possible that the genes under selection could influence telomere biology diseases. As a group, there appears to be less diversity and differentiation in telomere biology genes than in genes with different functions, possibly due to their critical role in telomere maintenance and chromosomal stability.
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Affiliation(s)
- L Mirabello
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD, USA
| | - M Yeager
- Core Genotyping Facility, National Cancer Institute, Division of Cancer Epidemiology and Genetics, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD, USA
| | - S Chowdhury
- Core Genotyping Facility, National Cancer Institute, Division of Cancer Epidemiology and Genetics, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD, USA
| | - L Qi
- Core Genotyping Facility, National Cancer Institute, Division of Cancer Epidemiology and Genetics, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD, USA
| | - X Deng
- Core Genotyping Facility, National Cancer Institute, Division of Cancer Epidemiology and Genetics, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD, USA
| | - Z Wang
- Core Genotyping Facility, National Cancer Institute, Division of Cancer Epidemiology and Genetics, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD, USA
| | - A Hutchinson
- Core Genotyping Facility, National Cancer Institute, Division of Cancer Epidemiology and Genetics, SAIC-Frederick, Inc., NCI-Frederick, Frederick, MD, USA
| | - S A Savage
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD, USA
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21
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Hou L, Zhang X, Gawron AJ, Liu J. Surrogate tissue telomere length and cancer risk: shorter or longer? Cancer Lett 2012; 319:130-135. [PMID: 22269209 DOI: 10.1016/j.canlet.2012.01.028] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Revised: 01/13/2012] [Accepted: 01/16/2012] [Indexed: 12/24/2022]
Abstract
Telomeres play a critical role in chromosome stability. Telomere length (TL) shortening is a risk factor for cancers. Measuring TL in surrogate tissues that can be easily collected may provide a potential tool for early detection of cancers. A number of studies on surrogate tissue TL and cancer risks have been conducted and results are inconsistent, including positive, negative, or null associations. In this article, we reviewed the published data on surrogate tissue TL in relation to cancer risks, discussed the possible reasons for the differences in the results and future directions and challenges for this line of research.
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Affiliation(s)
- Lifang Hou
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, 680 N. Lake Shore Drive, Chicago, IL 60611, United States; The Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, 303 E. Superior Street, Chicago, IL 60611, United States.
| | - Xiao Zhang
- Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, 680 N. Lake Shore Drive, Chicago, IL 60611, United States
| | - Andrew J Gawron
- Division of Gastroenterology and Hepatology, Department of Medicine, Feinberg School of Medicine, Northwestern University, 676 N. St. Clair, Chicago, IL 60611, United States
| | - Jie Liu
- Department of Digestive Diseases of Huashan Hospital, Fudan University, 12 Middle Wulumuqi Road, Shanghai 200040, PR China.
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Terry KL, Tworoger SS, Vitonis AF, Wong J, Titus-Ernstoff L, De Vivo I, Cramer DW. Telomere length and genetic variation in telomere maintenance genes in relation to ovarian cancer risk. Cancer Epidemiol Biomarkers Prev 2012; 21:504-12. [PMID: 22267287 DOI: 10.1158/1055-9965.epi-11-0867] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Telomeres protect chromosomal ends, shorten with cellular division, and signal cellular senescence, but unchecked telomere attrition can lead to telomere dysfunction, upregulation of telomerase, and carcinogenesis. Shorter telomeres in peripheral blood leukocytes (PBL) have been associated with elevated cancer risk. Furthermore, genetic variants in and around the TERT gene have been implicated in carcinogenesis. METHODS We measured relative telomere length (RTL) in PBLs of 911 cases and 948 controls from the New England case-control (NECC) study, a population-based study of ovarian cancer. In addition, we assessed germ line genetic variation in five telomere maintenance genes among 2,112 cases and 2,456 controls from the NECC study and the Nurses' Health Study, a prospective cohort study. ORs and 95% CIs were estimated by logistic regression. RESULTS Overall, we observed no differences in telomere length between cases and controls. Compared with women with RTL in the longest tertile, women with RTL in the shortest tertile had no increase in risk (OR = 1.01, 95% CI: 0.80-1.28). However, several SNPs in the TERT gene, including rs2736122, rs4246742, rs4975605, rs10069690, rs2736100, rs2853676, and rs7726159, were significantly associated with ovarian cancer risk. We observed a significant gene-level association between TERT and ovarian cancer risk (P = 0.00008). CONCLUSION Our observations suggest that genetic variation in the TERT gene may influence ovarian cancer risk, but the association between average telomere length in PBLs and ovarian cancer remains unclear. IMPACT The role of telomeres in ovarian carcinogenesis remains unsettled and warrants further investigation.
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Affiliation(s)
- Kathryn L Terry
- Obstetrics and Gynecology Epidemiology Center, Department of Obstetrics and Gynecology, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA.
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Khan S, Raghuram GV, Bhargava A, Pathak N, Chandra DH, Jain SK, Mishra PK. Role and clinical significance of lymphocyte mitochondrial dysfunction in type 2 diabetes mellitus. Transl Res 2011; 158:344-59. [PMID: 22061042 DOI: 10.1016/j.trsl.2011.08.007] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 08/20/2011] [Accepted: 08/22/2011] [Indexed: 12/17/2022]
Abstract
Lymphocyte homeostasis in type 2 diabetes mellitus (T2DM) is associated with increased susceptibility to infections. Mitochondrial oxidative stress is implicated primarily in the immune pathophysiology of diabetes; however, the molecular underpinnings of lymphocyte mitochondrial dysfunction and ensuing downstream cellular effects are hitherto unreported. Both in early diagnosed patients and patients with late complications, we observed an inverse correlation between mitochondrial DNA content in lymphocytes and hemoglobin A1 (HbA1c) levels. This relation established for the first time might serve as a general, yet direct, predictor or indicator for mitochondrial dysfunction in T2DM. Compared with controls, nuclear DNA damage response was higher (P ≤ 0.001) in diabetic subjects with increased accumulation of phospho-ataxia-telangiectasia (ATM), γ-H2AX, along with active recruitment of repair proteins (Mre11, Rad50, and Nbs1). A higher frequency (>2%) of stable chromosomal anomalies with loss of telomere integrity was observed in cases with late complications. A significant decrease (P ≤ 0.001) in enzyme activity of complex II, III, and IV of mitochondrial respiratory chain was evident in both diabetic groups in comparison with healthy controls. Activation in the cascade of nuclear factor kappa-beta (NF-κβ)-mediated feed-forward proinflammatory cytokine response was noted among T2DM subjects. Increased oxidative stress, mitochondrial membrane depolarization, activation of caspase-3, and PARP observed in diabetic groups indicated bax triggered mitochondrial mediated cellular apoptosis. Our results provide the first insights of lymphocyte mitochondrial dysfunction that might be helpful in explaining the clinical significance of immunologic perturbation observed in type 2 diabetic conditions. Our data also indicate that maneuvering through the mitochondrial function might be a viable, indirect method to modulate lymphocyte homeostasis in T2DM.
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Affiliation(s)
- Saba Khan
- Research Wing, Bhopal Memorial Hospital & Research Centre, Bhopal, India
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Jaworowska E, Trubicka J, Lener MR, Masojć B, Złowocka-Perłowska E, McKay JD, Renard H, Oszutowska D, Wokołorczyk D, Lubiński J, Grodzki T, Serwatowski P, Nej-Wołosiak K, Tołoczko-Grabarek A, Sikorski A, Słojewski M, Jakubowska A, Cybulski C, Lubiński J, Scott RJ. Smoking related cancers and loci at chromosomes 15q25, 5p15, 6p22.1 and 6p21.33 in the Polish population. PLoS One 2011; 6:e25057. [PMID: 21966413 PMCID: PMC3178595 DOI: 10.1371/journal.pone.0025057] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2011] [Accepted: 08/23/2011] [Indexed: 12/17/2022] Open
Abstract
Genetic factors associated with the risk of smoking related cancers have until recently remained elusive. Since the publication of a genome-wide association study (GWAS) on lung cancer new genetic loci have been identified that appear to be associated with disease risk. In this replication study we genotyped 14 single nucleotide polymorphisms (SNPs) located at the 5p12.3-p15.33, 6p21.3-p22.1, 6q23-q27 and 15q25.1 loci in 874 lung, 450 bladder, 418 laryngeal cancer cases and cancer-free controls, matched by year of birth and sex to the cases. Our results revealed that loci in the chromosome region 15q25.1 (rs16969968[A], rs8034191[G]) and 5p15 (rs402710[T]) are associated with lung cancer risk in the Polish population (smoking status adjusted OR = 1.45, 1.35, 0.77; p ≤ 0.0001, 0.0005, 0.002; 95%CI 1.23-1.72, 1.14-1.59, 0.66-0.91 respectively). None of the other regions analyzed herein were implicated in the risk of lung, bladder or laryngeal cancer. This study supports previous findings on lung cancer but fails to show association of SNPs located in 15q25.1 and 5p15 region with other smoking related cancers like bladder and laryngeal cancer.
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Affiliation(s)
- Ewa Jaworowska
- Department of Otolaryngology and Laryngological Oncology, Pomeranian Medical University, Szczecin, Poland
| | - Joanna Trubicka
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Marcin R. Lener
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Bartłomiej Masojć
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
- Department of Radiotherapy, Western Pomeranian Oncology Center, Szczecin, Poland
- * E-mail:
| | - Elżbieta Złowocka-Perłowska
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - James D. McKay
- International Agency for Research on Cancer (IARC), Department of Genetic Epidemiology, Lyon, France
| | - Hélène Renard
- International Agency for Research on Cancer (IARC), Department of Genetic Epidemiology, Lyon, France
| | - Dorota Oszutowska
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Dominika Wokołorczyk
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Jakub Lubiński
- Department of Otolaryngology and Laryngological Oncology, Pomeranian Medical University, Szczecin, Poland
| | - Tomasz Grodzki
- Regional Hospital for Lung Diseases, Szczecin-Zdunowo, Poland
| | | | - Katarzyna Nej-Wołosiak
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Aleksandra Tołoczko-Grabarek
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Andrzej Sikorski
- Department of Urology and Urological Oncology, Pomeranian Medical University, Szczecin, Poland
| | - Marcin Słojewski
- Department of Urology and Urological Oncology, Pomeranian Medical University, Szczecin, Poland
| | - Anna Jakubowska
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Cezary Cybulski
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Jan Lubiński
- International Hereditary Cancer Center, Department of Genetics and Pathomorphology, Pomeranian Medical University, Szczecin, Poland
| | - Rodney J. Scott
- Discipline of Medical Genetics, University of Newcastle and The Hunter Medical Research Institute, Newcastle, New South Wales, Australia
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Prescott J, Kraft P, Chasman DI, Savage SA, Mirabello L, Berndt SI, Weissfeld JL, Han J, Hayes RB, Chanock SJ, Hunter DJ, De Vivo I. Genome-wide association study of relative telomere length. PLoS One 2011; 6:e19635. [PMID: 21573004 PMCID: PMC3091863 DOI: 10.1371/journal.pone.0019635] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2010] [Accepted: 04/11/2011] [Indexed: 02/07/2023] Open
Abstract
Telomere function is essential to maintaining the physical integrity of linear chromosomes and healthy human aging. The probability of forming proper telomere structures depends on the length of the telomeric DNA tract. We attempted to identify common genetic variants associated with log relative telomere length using genome-wide genotyping data on 3,554 individuals from the Nurses' Health Study and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial that took part in the National Cancer Institute Cancer Genetic Markers of Susceptibility initiative for breast and prostate cancer. After genotyping 64 independent SNPs selected for replication in additional Nurses' Health Study and Women's Genome Health Study participants, we did not identify genome-wide significant loci; however, we replicated the inverse association of log relative telomere length with the minor allele variant [C] of rs16847897 at the TERC locus (per allele β = −0.03, P = 0.003) identified by a previous genome-wide association study. We did not find evidence for an association with variants at the OBFC1 locus or other loci reported to be associated with telomere length. With this sample size we had >80% power to detect β estimates as small as ±0.10 for SNPs with minor allele frequencies of ≥0.15 at genome-wide significance. However, power is greatly reduced for β estimates smaller than ±0.10, such as those for variants at the TERC locus. In general, common genetic variants associated with telomere length homeostasis have been difficult to detect. Potential biological and technical issues are discussed.
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Affiliation(s)
- Jennifer Prescott
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Molecular and Genetic Epidemiology, Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Peter Kraft
- Program in Molecular and Genetic Epidemiology, Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America
| | - Daniel I. Chasman
- Donald W. Reynolds Center for Cardiovascular Research, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Sharon A. Savage
- Division of Cancer Epidemiology and Genetics, Department of Health and Human Services, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Lisa Mirabello
- Division of Cancer Epidemiology and Genetics, Department of Health and Human Services, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Sonja I. Berndt
- Division of Cancer Epidemiology and Genetics, Department of Health and Human Services, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Joel L. Weissfeld
- University of Pittsburgh Cancer Institute, Pittsburgh, Pennsylvania, United States of America
| | - Jiali Han
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Molecular and Genetic Epidemiology, Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America
- Department of Dermatology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Richard B. Hayes
- Division of Epidemiology, New York University Medical Center, New York, New York, United States of America
| | - Stephen J. Chanock
- Division of Cancer Epidemiology and Genetics, Department of Health and Human Services, National Cancer Institute, National Institutes of Health, Bethesda, Maryland, United States of America
| | - David J. Hunter
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Molecular and Genetic Epidemiology, Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America
- Program in Medical and Population Genetics, Broad Institute of Harvard and MIT, Cambridge, Massachusetts, United States of America
| | - Immaculata De Vivo
- Channing Laboratory, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, United States of America
- Program in Molecular and Genetic Epidemiology, Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts, United States of America
- * E-mail:
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Abstract
Aging is a biological process that affects most cells, organisms and species. Human aging is associated with increased susceptibility to a variety of chronic diseases, including cardiovascular disease, Type 2 diabetes, neurological diseases and cancer. Despite the remarkable progress made during the last two decades, our understanding of the biology of aging remains incomplete. Telomere biology has recently emerged as an important player in the aging and disease process.
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Lobetti-Bodoni C, Bernocco E, Genuardi E, Boccadoro M, Ladetto M. Telomeres and telomerase in normal and malignant B-cells. Hematol Oncol 2011; 28:157-67. [PMID: 20213664 DOI: 10.1002/hon.937] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The telomeric checkpoint is emerging as a critical sensor of cellular damage, playing a major role in human aging and cancer development. In the meantime, telomere biology is rapidly evolving from a basic discipline to a translational branch, capable of providing major hints for biomarker development, risk assessment and targeted treatment of cancer. These advances have a number of implications in the biology of lymphoid tumours. Moreover, there is considerable interest in the potential role of telomeric dysfunction in the wide array of immunological abnormalities, grouped under the definition of 'immunosenescence'. This review will summarize the impact of recent advances in telomere biology on the physiology and pathology of the B lymphocyte, with special interest in immunosenescence and lymphomagenesis.
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Affiliation(s)
- Chiara Lobetti-Bodoni
- Department of Experimental Oncology, Division of Hematology, University of Torino, Italy
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Mirabello L, Yu K, Kraft P, De Vivo I, Hunter DJ, Prescott J, Wong JYY, Chatterjee N, Hayes RB, Savage SA. The association of telomere length and genetic variation in telomere biology genes. Hum Mutat 2010; 31:1050-8. [PMID: 20597107 DOI: 10.1002/humu.21314] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Telomeres cap chromosome ends and are critical for genomic stability. Many telomere-associated proteins are important for telomere length maintenance. Recent genome-wide association studies (GWAS) have identified single nucleotide polymorphisms (SNPs) in genes encoding telomere-associated proteins (RTEL1 and TERT-CLPTM1) as markers of cancer risk. We conducted an association study of telomere length and 743 SNPs in 43 telomere biology genes. Telomere length in peripheral blood DNA was determined by Q-PCR in 3,646 participants from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial and Nurses' Health Study. We investigated associations by SNP, gene, and pathway (functional group). We found no associations between telomere length and SNPs in TERT-CLPTM1L or RTEL1. Telomere length was not significantly associated with specific functional groups. Thirteen SNPs from four genes (MEN1, MRE11A, RECQL5, and TNKS) were significantly associated with telomere length. The strongest findings were in MEN1 (gene-based P=0.006), menin, which associates with the telomerase promoter and may negatively regulate telomerase. This large association study did not find strong associations with telomere length. The combination of limited diversity and evolutionary conservation suggest that these genes may be under selective pressure. More work is needed to explore the role of genetic variants in telomere length regulation.
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Affiliation(s)
- Lisa Mirabello
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892, USA.
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Prescott J, McGrath M, Lee IM, Buring JE, De Vivo I. Telomere length and genetic analyses in population-based studies of endometrial cancer risk. Cancer 2010; 116:4275-82. [PMID: 20549820 DOI: 10.1002/cncr.25328] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Telomeres are protective structures at the ends of linear chromosomes, regulated by a host of associated proteins. When telomeres become dysfunctional, genomic instability ensues. The vast majority of cells undergo apoptosis, although a rare cell may survive and become tumorigenic. METHODS The authors used conditional logistic regression to examine relative telomere length in peripheral blood leukocytes, genetic variants at telomere maintenance gene loci (TERT, TNKS2, POT1, TERF1, TERF2), and endometrial cancer risk in case-control studies nested within the Nurses' Health Study and the Women's Health Study. RESULTS Relative telomere length was significantly inversely correlated with body mass index and weight gain since age 18 years. The authors did not observe a relationship between relative telomere length and endometrial cancer risk. Women in the shortest quartile had a multivariate-adjusted odds ratio (OR) of 1.20 (95% confidence interval [95% CI], 0.73-1.96; P for trend = .37) compared with women in the longest quartile. The authors found an elevation in endometrial cancer risk among women carrying at least 1 minor allele of RS2736122 (TERT; OR, 1.18; 95% CI, 1.01-1.38) or RS12412538 (TNKS2; OR, 1.16; 95% CI, 1.00-1.34). CONCLUSIONS Relative telomere length was not associated with endometrial cancer risk. Other aspects of telomere maintenance remain to be explored.
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Affiliation(s)
- Jennifer Prescott
- Department of Epidemiology, Harvard School of Public Health, Boston, Massachusetts 02115, USA
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Abstract
Telomerase and the control of telomere length are intimately linked to the process of tumourigenesis in humans. Here I review the evidence that variation at the 5p15.33 locus, which contains theTERTgene (encoding the catalytic subunit of telomerase), might play a role in the determination of cancer risk. Mutations in the coding regions ofTERTcan affect telomerase activity and telomere length, and create severe clinical phenotypes, including bone marrow failure syndromes and a substantive increase in cancer frequency. Variants within theTERTgene have been associated with increased risk of haematological malignancies, including myelodysplastic syndrome and acute myeloid leukaemia as well as chronic lymphocytic leukaemia. Furthermore, there is good evidence from a number of independent genome-wide association studies to implicate variants at the 5p15.33 locus in cancer risk at several different sites: lung cancer, basal cell carcinoma and pancreatic cancer show strong associations, while bladder, prostate and cervical cancer and glioma also show risk alleles in this region. Thus, multiple independent lines of evidence have implicated variation in theTERTgene as a risk factor for cancer. The mechanistic basis of these risk variants is yet to be established; however, the basic biology suggests that telomere length control is a tantalising candidate mechanism underlying cancer risk.
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Varadi V, Brendle A, Grzybowska E, Johansson R, Enquist K, Butkiewicz D, Pamula-Pilat J, Pekala W, Hemminki K, Lenner P, Försti A. A functional promoter polymorphism in the TERT gene does not affect inherited susceptibility to breast cancer. ACTA ACUST UNITED AC 2009; 190:71-4. [PMID: 19380022 DOI: 10.1016/j.cancergencyto.2008.12.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Accepted: 11/14/2008] [Indexed: 01/27/2023]
Abstract
Telomere dysfunction is a key mechanism in cancer development. The human telomerase reverse transcriptase (TERT) is the rate-limiting catalytic subunit of the telomerase enzyme, which is necessary for the maintenance of telomere DNA length, chromosomal stability, and cellular immortality. In our attempt to identify functional polymorphisms in the TERT gene and their effect on breast cancer risk, we sequenced the promoter of the gene and identified three single nucleotide polymorphisms (SNPs) with a frequency of at least 10%. One of these SNPs, rs2853669 (-244 T > C), has been shown to affect telomerase activity and telomere length. Recently, this SNP has been suggested to affect familial breast cancer risk. In our case-control study using two large breast cancer sample series, including one with 841 cases with inherited susceptibility to breast cancer, we did not find any association with familial or sporadic breast cancer risk. This well-powered study excludes an effect of the functional -244 T > C SNP and two other correlated SNPs on breast cancer risk.
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Affiliation(s)
- Verena Varadi
- Division of Molecular Genetic Epidemiology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, D-69120 Heidelberg, Germany.
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Hosgood HD, Cawthon R, He X, Chanock S, Lan Q. Genetic variation in telomere maintenance genes, telomere length, and lung cancer susceptibility. Lung Cancer 2009; 66:157-61. [PMID: 19285750 DOI: 10.1016/j.lungcan.2009.02.005] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2008] [Revised: 02/05/2009] [Accepted: 02/07/2009] [Indexed: 01/13/2023]
Abstract
Telomeres are responsible for the protection of the chromosome ends and shortened telomere length has been associated with risk of multiple cancers. Genetic variation in telomere-related genes may alter cancer risk associated with telomere length. Using lung cancer cases (n=120) and population-based controls (n=110) from Xuanwei, China, we analyzed telomere length separately and in conjunction with single nucleotide polymorphisms in the telomere maintenance genes POT1, TERT, and TERF2, which we have previously reported were associated with risk of lung cancer in this study. POT1 rs10244817, TERT rs2075786, and TERF2 rs251796 were significantly associated with lung cancer (p(trend)< or =0.05). The shortest tertile of telomere length was not significantly associated with risk of lung cancer (OR=1.58; 95% CI=0.79-3.18) when compared to the longest tertile of telomere length. When stratified by genotype, there was a suggestion of a dose-response relationship between tertiles of telomere length and risk of lung cancer among the POT1 rs10244817 common variant carriers (OR (95% CI)=1.33 (0.47-3.75), 3.30 (1.14-9.56), respectively) but not among variant genotype carriers (p(interaction)=0.05). Our findings provide evidence that telomere length and genetic variation in telomere maintenance genes may be associated with risk of lung cancer susceptibility and warrant replication in larger studies.
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Affiliation(s)
- H Dean Hosgood
- Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Bethesda, MD, United States.
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McKay JD, Hung RJ, Gaborieau V, Boffetta P, Chabrier A, Byrnes G, Zaridze D, Mukeria A, Szeszenia-Dabrowska N, Lissowska J, Rudnai P, Fabianova E, Mates D, Bencko V, Foretova L, Janout V, McLaughlin J, Shepherd F, Montpetit A, Narod S, Krokan HE, Skorpen F, Elvestad MB, Vatten L, Njølstad I, Axelsson T, Chen C, Goodman G, Barnett M, Loomis MM, Lubiñski J, Matyjasik J, Lener M, Oszutowska D, Field J, Liloglou T, Xinarianos G, Cassidy A, Vineis P, Clavel-Chapelon F, Palli D, Tumino R, Krogh V, Panico S, González CA, Ramón Quirós J, Martínez C, Navarro C, Ardanaz E, Larrañaga N, Kham KT, Key T, Bueno-de-Mesquita HB, Peeters PH, Trichopoulou A, Linseisen J, Boeing H, Hallmans G, Overvad K, Tjønneland A, Kumle M, Riboli E, Zelenika D, Boland A, Delepine M, Foglio M, Lechner D, Matsuda F, Blanche H, Gut I, Heath S, Lathrop M, Brennan P. Lung cancer susceptibility locus at 5p15.33. Nat Genet 2008; 40:1404-6. [PMID: 18978790 DOI: 10.1038/ng.254] [Citation(s) in RCA: 448] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2008] [Accepted: 09/10/2008] [Indexed: 01/16/2023]
Abstract
We carried out a genome-wide association study of lung cancer (3,259 cases and 4,159 controls), followed by replication in 2,899 cases and 5,573 controls. Two uncorrelated disease markers at 5p15.33, rs402710 and rs2736100 were detected by the genome-wide data (P = 2 x 10(-7) and P = 4 x 10(-6)) and replicated by the independent study series (P = 7 x 10(-5) and P = 0.016). The susceptibility region contains two genes, TERT and CLPTM1L, suggesting that one or both may have a role in lung cancer etiology.
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Affiliation(s)
- James D McKay
- International Agency for Research on Cancer (IARC), Lyon, France
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TINF2 mutations result in very short telomeres: analysis of a large cohort of patients with dyskeratosis congenita and related bone marrow failure syndromes. Blood 2008; 112:3594-600. [PMID: 18669893 PMCID: PMC2572788 DOI: 10.1182/blood-2008-05-153445] [Citation(s) in RCA: 223] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Dyskeratosis congenita (DC) is a multisystem bone marrow failure syndrome characterized by a triad of mucocutaneous abnormalities and a predisposition to cancer. The genetic basis of DC remains unknown in more than 60% of patients. Mutations have been identified in components of the telomerase complex (dyskerin, TERC, TERT, NOP10, and NHP2), and recently in one component of the shelterin complex TIN2 (gene TINF2). To establish the role of TINF2 mutations, we screened DNA from 175 uncharacterised patients with DC as well as 244 patients with other bone marrow failure disorders. Heterozygous coding mutations were found in 33 of 175 previously uncharacterized DC index patients and 3 of 244 other patients. A total of 21 of the mutations affected amino acid 282, changing arginine to histidine (n = 14) or cysteine (n = 7). A total of 32 of 33 patients with DC with TINF2 mutations have severe disease, with most developing aplastic anaemia by the age of 10 years. Telomere lengths in patients with TINF2 mutations were the shortest compared with other DC subtypes, but TERC levels were normal. In this large series, TINF2 mutations account for approximately 11% of all DC, but they do not play a significant role in patients with related disorders. This study emphasises the role of defective telomere maintenance on human disease.
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Savage SA, Gerstenblith MR, Goldstein AM, Mirabello L, Fargnoli MC, Peris K, Landi MT. Nucleotide diversity and population differentiation of the melanocortin 1 receptor gene, MC1R. BMC Genet 2008; 9:31. [PMID: 18402696 PMCID: PMC2324112 DOI: 10.1186/1471-2156-9-31] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2007] [Accepted: 04/10/2008] [Indexed: 01/27/2023] Open
Abstract
Background The melanocortin 1 receptor gene (MC1R) is responsible for normal pigment variation in humans and is highly polymorphic with numerous population-specific alleles. Some MC1R variants have been associated with skin cancer risk. Results Allele frequency data were compiled on 55 single nucleotide polymorphisms from seven geographically distinct human populations (n = 2306 individuals). MC1R nucleotide diversity, π, was much higher (10.1 × 10-4) than in other genes for all subjects. A large degree of population differentiation, determined by FST, was also present, particularly between Asia and all other populations, due to the p.R163Q (c.488 G>A) polymorphism. The least amount of differentiation was between the United States, Northern Europe, and Southern Europe. Tajima's D statistic suggested the presence of positive selection in individuals from Europe. Conclusion This study further quantifies the degree of population-specific genetic variation and suggests that positive selection may be present in European populations in MC1R.
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Affiliation(s)
- Sharon A Savage
- Clinical Genetics Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, USA.
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Savage SA, Giri N, Baerlocher GM, Orr N, Lansdorp PM, Alter BP. TINF2, a component of the shelterin telomere protection complex, is mutated in dyskeratosis congenita. Am J Hum Genet 2008; 82:501-9. [PMID: 18252230 DOI: 10.1016/j.ajhg.2007.10.004] [Citation(s) in RCA: 293] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2007] [Revised: 09/26/2007] [Accepted: 10/05/2007] [Indexed: 12/25/2022] Open
Abstract
Patients with dyskeratosis congenita (DC), a heterogeneous inherited bone marrow failure syndrome, have abnormalities in telomere biology, including very short telomeres and germline mutations in DKC1, TERC, TERT, or NOP10, but approximately 60% of DC patients lack an identifiable mutation. With the very short telomere phenotype and a highly penetrant, rare disease model, a linkage scan was performed on a family with autosomal-dominant DC and no mutations in DKCI, TERC, or TERT. Evidence favoring linkage was found at 2p24 and 14q11.2, and this led to the identification of TINF2 (14q11.2) mutations, K280E, in the proband and her five affected relatives and TINF2 R282H in three additional unrelated DC probands, including one with Revesz syndrome; a fifth DC proband had a R282S mutation. TINF2 mutations were not present in unaffected relatives, DC probands with mutations in DKC1, TERC, or TERT or 298 control subjects. We demonstrate that a fifth gene, TINF2, is mutated in classical DC and, for the first time, in Revesz syndrome. This represents the first shelterin complex mutation linked to human disease and confirms the role of very short telomeres as a diagnostic test for DC.
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Savage SA, Chanock SJ, Lissowska J, Brinton LA, Richesson D, Peplonska B, Bardin-Mikolajczak A, Zatonski W, Szeszenia-Dabrowska N, Garcia-Closas M. Genetic variation in five genes important in telomere biology and risk for breast cancer. Br J Cancer 2007; 97:832-6. [PMID: 17848914 PMCID: PMC2360388 DOI: 10.1038/sj.bjc.6603934] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Telomeres, consisting of TTAGGG nucleotide repeats and a protein complex at chromosome ends, are critical for maintaining chromosomal stability. Genomic instability, following telomere crisis, may contribute to breast cancer pathogenesis. Many genes critical in telomere biology have limited nucleotide diversity, thus, single nucleotide polymorphisms (SNPs) in this pathway could contribute to breast cancer risk. In a population-based study of 1995 breast cancer cases and 2296 controls from Poland, 24 SNPs representing common variation in POT1, TEP1, TERF1, TERF2 and TERT were genotyped. We did not identify any significant associations between individual SNPs or haplotypes and breast cancer risk; however, data suggested that three correlated SNPs in TERT (−1381C>T, −244C>T, and Ex2-659G>A) may be associated with reduced risk of breast cancer among individuals with a family history of breast cancer (odds ratios 0.73, 0.66, and 0.57, 95% confidence intervals 0.53–1.00, 0.46–0.95 and 0.39–0.84, respectively). In conclusion, our data do not support substantial overall associations between SNPs in telomere pathway genes and breast cancer risk. Intriguing associations with variants in TERT among women with a family history of breast cancer warrant follow-up in independent studies.
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Affiliation(s)
- S A Savage
- Division of Cancer Epidemiology and Genetics, Clinical Genetics Branch, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892, USA.
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Keegan CE, Hutz JE, Krause AS, Koehler K, Metherell LA, Boikos S, Stergiopoulos S, Clark AJL, Stratakis CA, Huebner A, Hammer GD. Novel polymorphisms and lack of mutations in the ACD gene in patients with ACTH resistance syndromes. Clin Endocrinol (Oxf) 2007; 67:168-74. [PMID: 17466001 DOI: 10.1111/j.1365-2265.2007.02855.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVE ACTH resistance is a feature of several human syndromes with known genetic causes, including familial glucocorticoid deficiency (types 1 and 2) and triple A syndrome. However, many patients with ACTH resistance lack an identifiable genetic aetiology. The human homolog of the Acd gene, mutated in a mouse model of adrenal insufficiency, was sequenced in 25 patients with a clinical diagnosis of familial glucocorticoid deficiency or triple A syndrome. DESIGN A 3.4 kilobase genomic fragment containing the entire ACD gene was analysed for mutations in all 25 patients. SETTING Samples were obtained by three investigators from different institutions. PATIENTS The primary cohort consisted of 25 unrelated patients, primarily of European or Middle Eastern descent, with a clinical diagnosis of either familial glucocorticoid deficiency (FGD) or triple A syndrome. Patients lacked mutations in other genes known to cause ACTH resistance, including AAAS for patients diagnosed with triple A syndrome and MC2R and MRAP for patients diagnosed with familial glucocorticoid deficiency. Thirty-five additional patients with adrenal disease phenotypes were added to form an expanded cohort of 60 patients. MEASUREMENTS Identification of DNA sequence changes in the ACD gene in the primary cohort and analysis of putative ACD haplotypes in the expanded cohort. RESULTS No disease-causing mutations were found, but several novel single nucleotide polymorphisms (SNPs) and two putative haplotypes were identified. The overall frequency of SNPs in ACD is low compared to other gene families. CONCLUSIONS No mutations were identified in ACD in this collection of patients with ACTH resistance phenotypes. However, the newly identified SNPs in ACD should be more closely examined for possible links to disease.
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Affiliation(s)
- Catherine E Keegan
- Department of Pediatrics, Division of Genetics, University of Michigan Medical School, 1150 W. Medical Center Drive, Ann Arbor, MI 48109, USA.
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Savage SA, Stewart BJ, Weksler BB, Baerlocher GM, Lansdorp PM, Chanock SJ, Alter BP. Mutations in the reverse transcriptase component of telomerase (TERT) in patients with bone marrow failure. Blood Cells Mol Dis 2006; 37:134-6. [PMID: 16934504 DOI: 10.1016/j.bcmd.2006.07.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2006] [Accepted: 07/12/2006] [Indexed: 11/28/2022]
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Sampson MJ, Hughes DA. Chromosomal telomere attrition as a mechanism for the increased risk of epithelial cancers and senescent phenotypes in type 2 diabetes. Diabetologia 2006; 49:1726-31. [PMID: 16791617 DOI: 10.1007/s00125-006-0322-4] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2006] [Accepted: 04/24/2006] [Indexed: 01/31/2023]
Abstract
Telomeres are the repeat DNA sequences at the end of chromosomes necessary for successful DNA replication and chromosomal integrity. Telomeres shorten at cell division at a rate determined by oxidative DNA damage, and cells are triggered into replicative senescence once telomeres shorten to a critical length. Telomere-related chromosomal maintenance also has a role in carcinogenesis. Type 2 diabetes is characterised by increased oxidative stress, increased oxidative DNA damage, senescent retinal and renal phenotypes, and an increased risk of epithelial malignancy. We suggest that increased oxidative DNA damage and telomere attrition in type 2 diabetes leads to: (1) carcinogenic telomere-dependent chromosomal non-reciprocal translocations, genomic instability, and the development of epithelial cancers; (2) senescent retinal and renal phenotypes (expressed as diabetic retinopathy and nephropathy); and (3) senescent vascular endothelial, monocyte-macrophage and vascular smooth muscle cells (expressed as endothelial dysfunction and accelerated atherogenesis). An adverse intrauterine environment leads to increased feto-placental oxidative stress and feto-placental oxidative DNA damage. We also suggest that intrauterine oxidative DNA damage and telomere shortening is another point at which increased oxidative stress could contribute to a pre-programmed increased risk of senescent phenotypes in adult offspring, characterised by type 2 diabetes and epithelial malignancy. These suggestions can be used to understand early glucose intolerance in the young children of type 1 diabetes pregnancies, poor cancer outcomes in type 2 diabetes, beta cell fatigue in type 2 diabetes and the absence of increased epithelial cancer risk in type 1 diabetes.
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Affiliation(s)
- M J Sampson
- School of Medicine, Health Policy and Practice, University of East Anglia, Norwich NR4 7UA, UK.
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Savage SA, Calado RT, Xin ZT, Ly H, Young NS, Chanock SJ. Genetic variation in telomeric repeat binding factors 1 and 2 in aplastic anemia. Exp Hematol 2006; 34:664-71. [PMID: 16647572 DOI: 10.1016/j.exphem.2006.02.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 01/26/2006] [Accepted: 02/08/2006] [Indexed: 11/27/2022]
Abstract
OBJECTIVE Abnormal telomere shortening has been observed in a subset of individuals with aplastic anemia (AA). We hypothesized that genetic variation in two genes critical in telomere biology, TERF1 and TERF2, could be a risk factor for AA. METHODS The proximal promoter and all coding regions of TERF1 and TERF2 were sequenced in 47 individuals with acquired AA. Regions with genetic variation were sequenced in an additional 95 AA patients and 289 healthy controls. Single nucleotide polymorphism (SNP) frequencies were analyzed using co-dominant and dominant models and haplotypes determined. Functional studies evaluated telomerase activity, telomere and telomeric overhang lengths, and TRF2 protein expression in select patients. RESULTS Two nonsynonymous amino acid changes were detected, one in exon 9 of TERF1 and another in exon 6 of TERF2. These sequence variants resulted in conservative amino acid changes and were not predicted to alter TRF1 or TRF2 protein expression or function. SNP and haplotype analyses in acquired AA patients suggested that one variant allele, in intron 9 of TERF1, and haplotype could be associated with increased risk for aplastic anemia (OR 1.59, 95% confidence interval 1.06-2.39, p = 0.033). TERF2 SNPs and haplotypes were not significantly associated with aplastic anemia. CONCLUSIONS It is possible that a common genetic variant in TERF1 is associated with risk for AA but additional studies are required. Highly penetrant, non-synonymous, or insertion-deletion mutations in TERF1 and TERF2 were not identified and therefore are not likely to be major genetic risk factors for the development of AA.
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Affiliation(s)
- Sharon A Savage
- Section of Genomic Variation, Pediatric Oncology Branch, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-4605, USA.
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Packer BR, Yeager M, Burdett L, Welch R, Beerman M, Qi L, Sicotte H, Staats B, Acharya M, Crenshaw A, Eckert A, Puri V, Gerhard DS, Chanock SJ. SNP500Cancer: a public resource for sequence validation, assay development, and frequency analysis for genetic variation in candidate genes. Nucleic Acids Res 2006; 34:D617-21. [PMID: 16381944 PMCID: PMC1347513 DOI: 10.1093/nar/gkj151] [Citation(s) in RCA: 220] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2005] [Revised: 10/28/2005] [Accepted: 10/28/2005] [Indexed: 11/12/2022] Open
Abstract
The SNP500Cancer database provides sequence and genotype assay information for candidate SNPs useful in mapping complex diseases, such as cancer. The database is an integral component of the NCI Cancer Genome Anatomy Project (http://cgap.nci.nih.gov). SNP500Cancer reports sequence analysis of anonymized control DNA samples (n = 102 Coriell samples representing four self-described ethnic groups: African/African-American, Caucasian, Hispanic and Pacific Rim). The website is searchable by gene, chromosome, gene ontology pathway, dbSNP ID and SNP500Cancer SNP ID. As of October 2005, the database contains >13 400 SNPs, 9124 of which have been sequenced in the SNP500Cancer population. For each analysed SNP, gene location and >200 bp of surrounding annotated sequence (including nearby SNPs) are provided, with frequency information in total and per subpopulation as well as calculation of Hardy-Weinberg equilibrium for each subpopulation. The website provides the conditions for validated sequencing and genotyping assays, as well as genotype results for the 102 samples, in both viewable and downloadable formats. A subset of sequence validated SNPs with minor allele frequency >5% are entered into a high-throughput pipeline for genotyping analysis to determine concordance for the same 102 samples. In addition, the results of genotype analysis for select validated SNP assays (defined as 100% concordance between sequence analysis and genotype results) are posted for an additional 280 samples drawn from the Human Diversity Panel (HDP). SNP500Cancer provides an invaluable resource for investigators to select SNPs for analysis, design genotyping assays using validated sequence data, choose selected assays already validated on one or more genotyping platforms, and select reference standards for genotyping assays. The SNP500Cancer database is freely accessible via the web page at http://snp500cancer.nci.nih.gov.
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Affiliation(s)
- Bernice R Packer
- Intramural Research Support Program, SAIC-Frederick, NCI-FCRDC, Frederick, MD, USA.
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