1
|
Mukherjee J, Johannessen TC, Ohba S, Chow TT, Jones L, Pandita A, Pieper RO. Mutant IDH1 Cooperates with ATRX Loss to Drive the Alternative Lengthening of Telomere Phenotype in Glioma. Cancer Res 2018; 78:2966-2977. [PMID: 29545335 PMCID: PMC10578296 DOI: 10.1158/0008-5472.can-17-2269] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 12/04/2017] [Accepted: 03/12/2018] [Indexed: 11/16/2022]
Abstract
A subset of tumors use a recombination-based alternative lengthening of telomere (ALT) pathway to resolve telomeric dysfunction in the absence of TERT. Loss-of-function mutations in the chromatin remodeling factor ATRX are associated with ALT but are insufficient to drive the process. Because many ALT tumors express the mutant isocitrate dehydrogenase IDH1 R132H, including all lower grade astrocytomas and secondary glioblastoma, we examined a hypothesized role for IDH1 R132H in driving the ALT phenotype during gliomagenesis. In p53/pRb-deficient human astrocytes, combined deletion of ATRX and expression of mutant IDH1 were sufficient to create tumorigenic cells with ALT characteristics. The telomere capping complex component RAP1 and the nonhomologous DNA end joining repair factor XRCC1 were each downregulated consistently in these tumorigenic cells, where their coordinate reexpression was sufficient to suppress the ALT phenotype. RAP1 or XRCC1 downregulation cooperated with ATRX loss in driving the ALT phenotype. RAP1 silencing caused telomere dysfunction in ATRX-deficient cells, whereas XRCC1 silencing suppressed lethal fusion of dysfunctional telomeres by allowing IDH1-mutant ATRX-deficient cells to use homologous recombination and ALT to resolve telomeric dysfunction and escape cell death. Overall, our studies show how expression of mutant IDH1 initiates telomeric dysfunction and alters DNA repair pathway preferences at telomeres, cooperating with ATRX loss to defeat a key barrier to gliomagenesis.Significance: Studies show how expression of mutant IDH1 initiates telomeric dysfunction and alters DNA repair pathway preferences at telomeres, cooperating with ATRX loss to defeat a key barrier to gliomagenesis and suggesting new therapeutic options to treat low-grade gliomas. Cancer Res; 78(11); 2966-77. ©2018 AACR.
Collapse
Affiliation(s)
- Joydeep Mukherjee
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California
| | - Tor-Christian Johannessen
- The Kristian Gerhard Jebsen Brain Tumor Research Centre, Department of Biomedicine, University of Bergen, Bergen, Norway
| | - Shigeo Ohba
- Department of Neurosurgery, Fujita Health University, Toyoake, Aichi, Japan
| | - Tracy T Chow
- Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California
| | - Lindsey Jones
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California
| | | | - Russell O Pieper
- Department of Neurological Surgery, University of California, San Francisco, San Francisco, California.
| |
Collapse
|
2
|
Kaya Z, Akkiprik M, Karabulut S, Peker I, Gullu Amuran G, Ozmen T, Gulluoglu BM, Kaya H, Ozer A. Comparison of telomere length and insulin-like growth factor-binding protein 7 promoter methylation between breast cancer tissues and adjacent normal tissues in Turkish women. J Clin Lab Anal 2016; 31. [PMID: 27775181 DOI: 10.1002/jcla.22083] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 09/18/2016] [Indexed: 02/03/2023] Open
Abstract
BACKGROUND Both insulin-like growth factor-binding protein 7 (IGFBP7) and telomere length (TL) are associated with proliferation and senescence of human breast cancer. This study assessed the clinical significance of both TL and IGFBP7 methylation status in breast cancer tissues compared with adjacent normal tissues. We also investigated whether IGFBP7 methylation status could be affecting TL. METHODS Telomere length was measured by quantitative PCR to compare tumors with their adjacent normal tissues. The IGFBP7 promoter methylation status was evaluated by methylation-specific PCR and its expression levels were determined by western blotting. RESULTS Telomeres were shorter in tumor tissues compared to controls (P<.0001). The mean TL was higher in breast cancer with invasive ductal carcinoma (IDC; n=72; P=.014) compared with other histological type (n=29), and TL in IDC with HER2 negative (n=53; P=.017) was higher than TL in IDC with HER2 positive (n=19). However, telomeres were shortened in advanced stages and growing tumors. IGFBP7 methylation was observed in 90% of tumor tissues and 59% of controls (P=.0002). Its frequency was significantly higher in IDC compared with invasive mixed carcinoma (IMC; P=.002) and it was not correlated either with protein expression or the other clinicopathological parameters. CONCLUSION These results suggest that IGFBP7 promoter methylation and shorter TL in tumor compared with adjacent tissues may be predictive biomarkers for breast cancer. Telomere maintenance may be indicative of IDC and IDC with HER2 (-) of breast cancer. Further studies with larger number of cases are necessary to verify this association.
Collapse
Affiliation(s)
- Zehra Kaya
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey.,Medical Biology Department, School of Medicine, Yüzüncü Yıl University, Van, Turkey
| | - Mustafa Akkiprik
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey
| | - Sevgi Karabulut
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey.,Health Services Vocational School, Bayburt University, Bayburt, Turkey
| | - Irem Peker
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey
| | - Gokce Gullu Amuran
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey
| | - Tolga Ozmen
- General Surgery, School of Medicine, Marmara University, Istanbul, Turkey
| | | | - Handan Kaya
- Pathology Department, School of Medicine, Marmara University, Istanbul, Turkey
| | - Ayse Ozer
- Medical Biology Department, School of Medicine, Marmara University, Istanbul, Turkey
| |
Collapse
|
3
|
Clynes D, Jelinska C, Xella B, Ayyub H, Scott C, Mitson M, Taylor S, Higgs DR, Gibbons RJ. Suppression of the alternative lengthening of telomere pathway by the chromatin remodelling factor ATRX. Nat Commun 2015; 6:7538. [PMID: 26143912 PMCID: PMC4501375 DOI: 10.1038/ncomms8538] [Citation(s) in RCA: 206] [Impact Index Per Article: 22.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 05/19/2015] [Indexed: 02/08/2023] Open
Abstract
Fifteen per cent of cancers maintain telomere length independently of telomerase by the homologous recombination (HR)-associated alternative lengthening of telomeres (ALT) pathway. A unifying feature of these tumours are mutations in ATRX. Here we show that expression of ectopic ATRX triggers a suppression of the pathway and telomere shortening. Importantly ATRX-mediated ALT suppression is dependent on the histone chaperone DAXX. Re-expression of ATRX is associated with a reduction in replication fork stalling, a known trigger for HR and loss of MRN from telomeres. A G-quadruplex stabilizer partially reverses the effect of ATRX, inferring ATRX may normally facilitate replication through these sequences that, if they persist, promote ALT. We propose that defective telomere chromatinization through loss of ATRX promotes the persistence of aberrant DNA secondary structures, which in turn present a barrier to DNA replication, leading to replication fork stalling, collapse, HR and subsequent recombination-mediated telomere synthesis in ALT cancers. ATRX, a chromatin remodelling factor, is mutated in cancers that maintain telomere length by alternative lengthening of telomeres (ALT). Here, the authors show that ectopic expression of ATRX triggers telomere shortening, ALT suppression and reduced replication fork stalling.
Collapse
Affiliation(s)
- David Clynes
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Clare Jelinska
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Barbara Xella
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Helena Ayyub
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Caroline Scott
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Matthew Mitson
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Stephen Taylor
- Computational Biology Research Group, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Douglas R Higgs
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| | - Richard J Gibbons
- MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DS, UK
| |
Collapse
|
4
|
Episkopou H, Draskovic I, Van Beneden A, Tilman G, Mattiussi M, Gobin M, Arnoult N, Londoño-Vallejo A, Decottignies A. Alternative Lengthening of Telomeres is characterized by reduced compaction of telomeric chromatin. Nucleic Acids Res 2014; 42:4391-405. [PMID: 24500201 PMCID: PMC3985679 DOI: 10.1093/nar/gku114] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Proper telomeric chromatin configuration is thought to be essential for telomere homeostasis and stability. Previous studies in mouse suggested that loss of heterochromatin marks at telomeres might favor onset of Alternative Lengthening of Telomeres (ALT) pathway, by promoting homologous recombination. However, analysis of chromatin status at human ALT telomeres has never been reported. Here, using isogenic human cell lines and cellular hybrids, which rely either on telomerase or ALT to maintain telomeres, we show that chromatin compaction is reduced at ALT telomeres and this is associated with a global decrease in telomeric H3K9me3. This, subsequently, leads to upregulation of telomere transcription. Accordingly, restoration of a more condensed telomeric chromatin through telomerase-dependent elongation of short ALT telomeres reduces telomere transcription. We further show that loss of ATRX chromatin remodeler function, a frequent characteristic of ALT cells, is not sufficient to decrease chromatin condensation at telomeres nor to increase the expression of telomeric RNA species. These results offer new insight on telomeric chromatin properties in ALT cells and support the hypothesis that telomeric chromatin decondensation is important for ALT pathway.
Collapse
Affiliation(s)
- Harikleia Episkopou
- Genetic and Epigenetic Alterations of Genomes, de Duve Institute, Catholic University of Louvain, Brussels 1200, Belgium and Telomeres and Cancer Laboratory, Equipe Labellisée Ligue, UMR3244-UPMC-Institut Curie, Paris 75248, France
| | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Simeonova I, Jaber S, Draskovic I, Bardot B, Fang M, Bouarich-Bourimi R, Lejour V, Charbonnier L, Soudais C, Bourdon JC, Huerre M, Londono-Vallejo A, Toledo F. Mutant mice lacking the p53 C-terminal domain model telomere syndromes. Cell Rep 2013; 3:2046-58. [PMID: 23770245 DOI: 10.1016/j.celrep.2013.05.028] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 04/01/2013] [Accepted: 05/17/2013] [Indexed: 11/29/2022] Open
Abstract
Mutations in p53, although frequent in human cancers, have not been implicated in telomere-related syndromes. Here, we show that homozygous mutant mice expressing p53Δ31, a p53 lacking the C-terminal domain, exhibit increased p53 activity and suffer from aplastic anemia and pulmonary fibrosis, hallmarks of syndromes caused by short telomeres. Indeed, p53Δ31/Δ31 mice had short telomeres and other phenotypic traits associated with the telomere disease dyskeratosis congenita and its severe variant the Hoyeraal-Hreidarsson syndrome. Heterozygous p53+/Δ31 mice were only mildly affected, but decreased levels of Mdm4, a negative regulator of p53, led to a dramatic aggravation of their symptoms. Importantly, several genes involved in telomere metabolism were downregulated in p53Δ31/Δ31 cells, including Dyskerin, Rtel1, and Tinf2, which are mutated in dyskeratosis congenita, and Terf1, which is implicated in aplastic anemia. Together, these data reveal that a truncating mutation can activate p53 and that p53 plays a major role in the regulation of telomere metabolism.
Collapse
Affiliation(s)
- Iva Simeonova
- Genetics of Tumor Suppression, Institut Curie, Centre de Recherche, 26 rue d'Ulm, 75248 Paris Cedex 05, France
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
6
|
Methods of studying telomere damage induced by quadruplex-ligand complexes. Methods 2012; 57:93-9. [PMID: 22410593 DOI: 10.1016/j.ymeth.2012.02.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2011] [Revised: 02/16/2012] [Accepted: 02/20/2012] [Indexed: 01/08/2023] Open
Abstract
The burgeoning knowledge about the structure of telomeres and the roles of various factors involved in telomere maintenance provides several possible targets for pharmacological intervention. To date the area that has received major attention regarding drug discovery is the targeting the telomeric G-quadruplex (G4) structure. G4 ligands were initially designed to counteract telomerase action at telomeres. Surprisingly, their antiproliferative effects can occur in telomerase negative cells and follow kinetics, which cannot be merely explained by telomere shortening, suggesting that these compounds affect other pathways, not necessarily related to telomere biology. Impressively, it has been shown that polyaromatic compounds featuring end-stacking binding properties trigger a strong DNA damage response at telomeres. This is typical of the telomere deprotection occurring during cellular senescence or upon telomere injury. It emerged that the G4-interacting agents are more than simple telomerase inhibitors and that their direct target is rather telomere than telomerase. This review summarizes the most valid experimental approaches for studying the pharmacological telomere damage induced by G4-ligand complexes.
Collapse
|