1
|
Bortoletto S, Nunes-Souza E, Marchi R, Ruthes MO, Okano LM, Tofolo MV, Centa A, Fonseca AS, Rosolen D, Cavalli LR. MicroRNAs role in telomere length maintenance and telomerase activity in tumor cells. J Mol Med (Berl) 2024; 102:1089-1100. [PMID: 39042290 DOI: 10.1007/s00109-024-02467-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 06/24/2024] [Accepted: 06/25/2024] [Indexed: 07/24/2024]
Abstract
MiRNAs, a class of non-coding RNA molecules, have emerged as critical modulators of telomere length and telomerase activity by finely tuning the expression of target genes (and not gene targets) within signaling pathways involved in telomere homeostasis. The primary objective of this systematic review was to compile and synthesize the existing body of knowledge on the role, association, and involvement of miRNAs in telomere length. Additionally, the review explored the regulation, function, and activation mechanism of the human telomerase reverse transcriptase (hTERT) gene and telomerase activity in tumor cells. A comprehensive analysis of 47 selected articles revealed 40 distinct miRNAs involved in these processes. These miRNAs were shown to exert their function, in both clinical cases and cell line models, either directly or indirectly, regulating hTERT and telomerase activity through distinct molecular mechanisms. The regulatory roles of these miRNAs significantly affected major cancer phenotypes, with outcomes largely dependent on the tissue type and the cellular actions within the tumor cells, whereby they functioned as oncogenes or tumor suppressors. These findings strongly support the pivotal role of miRNAs in modulating telomere length and telomerase activity, thereby contributing to the intricate and complex regulation of telomere homeostasis in tumor cells. Moreover, they emphasize the potential of targeting miRNAs and key regulatory genes as therapeutic strategies to disrupt cancer cell growth and promote senescence, offering promising avenues for novel cancer treatments.
Collapse
Affiliation(s)
- Stéfanne Bortoletto
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil
| | - Emanuelle Nunes-Souza
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil
| | - Rafael Marchi
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil
| | - Mayara Oliveira Ruthes
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil
| | - Larissa M Okano
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil
| | - Maria Vitoria Tofolo
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil
| | - Ariana Centa
- Universidade Alto Vale do Rio do Peixe (UNIARP), Caçador, SC, Brazil
| | - Aline S Fonseca
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil
| | - Daiane Rosolen
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil
| | - Luciane R Cavalli
- Faculdades Pequeno Príncipe, Research Institute Pelé Pequeno Príncipe, Curitiba, PR, Brazil.
- Oncology Department, Lombardi Comprehensive Cancer Center, Georgetown University, Washington, DC, USA.
| |
Collapse
|
2
|
Burrow TA, Koneru B, Macha SJ, Sun W, Barr FG, Triche TJ, Reynolds CP. Prevalence of alternative lengthening of telomeres in pediatric sarcomas determined by the telomeric DNA C-circle assay. Front Oncol 2024; 14:1399442. [PMID: 39224814 PMCID: PMC11366626 DOI: 10.3389/fonc.2024.1399442] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Accepted: 07/26/2024] [Indexed: 09/04/2024] Open
Abstract
Introduction Alternative lengthening of telomeres (ALT) occurs in sarcomas and ALT cancers share common mechanisms of therapy resistance or sensitivity. Telomeric DNA C-circles are self-primed circular telomeric repeats detected with a PCR assay that provide a sensitive and specific biomarker exclusive to ALT cancers. We have previously shown that 23% of high-risk neuroblastomas are of the ALT phenotype. Here, we investigate the frequency of ALT in Ewing's family sarcoma (EFS), rhabdomyosarcoma (RMS), and osteosarcoma (OS) by analyzing DNA from fresh frozen primary tumor samples utilizing the real-time PCR C-circle Assay (CCA). Methods We reviewed prior publications on ALT detection in pediatric sarcomas. DNA was extracted from fresh frozen primary tumors, fluorometrically quantified, C-circles were selectively enriched by isothermal rolling cycle amplification and detected by real-time PCR. Results The sample cohort consisted of DNA from 95 EFS, 191 RMS, and 87 OS primary tumors. One EFS and 4 RMS samples were inevaluable. Using C-circle positive (CC+) cutoffs previously defined for high-risk neuroblastoma, we observed 0 of 94 EFS, 5 of 187 RMS, and 62 of 87 OS CC+ tumors. Conclusions Utilizing the ALT-specific CCA we observed ALT in 0% of EFS, 2.7% of RMS, and 71% of OS. These data are comparable to prior studies in EFS and OS using less specific ALT markers. The CCA can provide a robust and sensitive means of identifying ALT in sarcomas and has potential as a companion diagnostic for ALT targeted therapeutics.
Collapse
Affiliation(s)
- Trevor A. Burrow
- Department of Pediatrics, Texas Tech University Health Sciences Center School of Medicine Cancer Center, Lubbock, TX, United States
- Department of Translational Neuroscience and Pharmacology, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - Balakrishna Koneru
- Department of Pediatrics, Texas Tech University Health Sciences Center School of Medicine Cancer Center, Lubbock, TX, United States
| | - Shawn J. Macha
- Department of Pediatrics, Texas Tech University Health Sciences Center School of Medicine Cancer Center, Lubbock, TX, United States
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center Graduate School of Biomedical Sciences, Lubbock, TX, United States
| | - Wenyue Sun
- Laboratory of Pathology, National Cancer Institute, Bethesda, MD, United States
| | - Frederic G. Barr
- Laboratory of Pathology, National Cancer Institute, Bethesda, MD, United States
| | - Timothy J. Triche
- Children’s Hospital Los Angles, Department of Pathology and Laboratory Medicine, Keck School of Medicine of University of Southern California, Los Angeles, CA, United States
| | - C. Patrick Reynolds
- Department of Pediatrics, Texas Tech University Health Sciences Center School of Medicine Cancer Center, Lubbock, TX, United States
- Department of Translational Neuroscience and Pharmacology, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Cell Biology and Biochemistry, Texas Tech University Health Sciences Center Graduate School of Biomedical Sciences, Lubbock, TX, United States
| |
Collapse
|
3
|
Panda S, Roychowdhury T, Dutta A, Chakraborty S, Das T, Chatterjee S. ALTering Cancer by Triggering Telomere Replication Stress through the Stabilization of Promoter G-Quadruplex in SMARCAL1. ACS Chem Biol 2024; 19:1433-1439. [PMID: 38959478 DOI: 10.1021/acschembio.4c00285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024]
Abstract
Most of the human cancers are dependent on telomerase to extend the telomeres. But ∼10% of all cancers use a telomerase-independent, homologous recombination mediated pathway called alternative lengthening of telomeres (ALT). Due to the poor prognosis, ALT status is not being considered yet in the diagnosis of cancer. No such specific treatment is available to date for ALT positive cancers. ALT positive cancers are dependent on replication stress to deploy DNA repair pathways to the telomeres to execute homologous recombination mediated telomere extension. SMARCAL1 (SWI/SNF related, matrix-associated, actin-dependent regulator of chromatin, subfamily A-like 1) is associated with the ALT telomeres to resolve replication stress thus providing telomere stability. Thus, the dependency on replication stress regulatory factors like SMARCAL1 made it a suitable therapeutic target for the treatment of ALT positive cancers. In this study, we found a significant downregulation of SMARCAL1 expression by stabilizing the G-quadruplex (G4) motif found in the promoter of SMARCAL1 by potent G4 stabilizers, like TMPyP4 and BRACO-19. SMARCAL1 downregulation led toward the increased localization of PML (promyelocytic leukemia) bodies in ALT telomeres and triggered the formation of APBs (ALT-associated promyelocytic leukemia bodies) in ALT positive cell lines, increasing telomere replication stress and DNA damage at a genomic level. Induction of replication stress and hyper-recombinogenic phenotype in ALT positive cells mediated by G4 stabilizing molecules already highlighted their possible application as a new therapeutic window to target ALT positive tumors. In accordance with this, our study will also provide a valuable insight toward the development of G4-based ALT therapeutics targeting SMARCAL1.
Collapse
Affiliation(s)
- Suman Panda
- Department of Biophysics, Bose Institute, EN 80, Sector V, Bidhan Nagar, Kolkata 700091 West Bengal, India
| | - Tanaya Roychowdhury
- Sloan Kettering Institute, Memorial Sloan Kettering Cancer Center, 1275 York Ave, New York, New York 10065, United States of America
| | - Anindya Dutta
- Department of Biophysics, Bose Institute, EN 80, Sector V, Bidhan Nagar, Kolkata 700091 West Bengal, India
| | - Sourio Chakraborty
- Division of Molecular Medicine, Centenary Campus, Bose Institute, P-1/12 C.I.T. Scheme VII-M, Kolkata 700054, India
| | - Tanya Das
- Division of Molecular Medicine, Centenary Campus, Bose Institute, P-1/12 C.I.T. Scheme VII-M, Kolkata 700054, India
| | - Subhrangsu Chatterjee
- Department of Biophysics, Bose Institute, EN 80, Sector V, Bidhan Nagar, Kolkata 700091 West Bengal, India
| |
Collapse
|
4
|
Hakobyan M, Binder H, Arakelyan A. Pan-cancer analysis of telomere maintenance mechanisms. J Biol Chem 2024; 300:107392. [PMID: 38763334 PMCID: PMC11225560 DOI: 10.1016/j.jbc.2024.107392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 04/28/2024] [Accepted: 05/13/2024] [Indexed: 05/21/2024] Open
Abstract
Telomeres, protective caps at chromosome ends, maintain genomic stability and control cell lifespan. Dysregulated telomere maintenance mechanisms (TMMs) are cancer hallmarks, enabling unchecked cell proliferation. We conducted a pan-cancer evaluation of TMM using RNA sequencing data from The Cancer Genome Atlas for 33 different cancer types and analyzed the activities of telomerase-dependent (TEL) and alternative lengthening of telomeres (ALT) TMM pathways in detail. To further characterize the TMM profiles, we categorized the tumors based on their ALT and TEL TMM pathway activities into five major phenotypes: ALT high TEL low, ALT low TEL low, ALT middle TEL middle, ALT high TEL high, and ALT low TEL high. These phenotypes refer to variations in telomere maintenance strategies, shedding light on the heterogeneous nature of telomere regulation in cancer. Moreover, we investigated the clinical implications of TMM phenotypes by examining their associations with clinical characteristics and patient outcomes. Specific TMM profiles were linked to specific survival patterns, emphasizing the potential of TMM profiling as a prognostic indicator and aiding in personalized cancer treatment strategies. Gene ontology analysis of the TMM phenotypes unveiled enriched biological processes associated with cell cycle regulation (both TEL and ALT), DNA replication (TEL), and chromosome dynamics (ALT) showing that telomere maintenance is tightly intertwined with cellular processes governing proliferation and genomic stability. Overall, our study provides an overview of the complexity of transcriptional regulation of telomere maintenance mechanisms in cancer.
Collapse
Affiliation(s)
- Meline Hakobyan
- Bioinformatics Group, Institute of Molecular Biology NAS RA, Yerevan, Armenia.
| | - Hans Binder
- Interdisciplinary Centre for Bioinformatics, University of Leipzig, Leipzig, Germany; Armenian Bioinformatics Institute, Yerevan, Armenia
| | - Arsen Arakelyan
- Bioinformatics Group, Institute of Molecular Biology NAS RA, Yerevan, Armenia
| |
Collapse
|
5
|
Liu X, Wang J, Wu LJ, Trinh B, Tsai RYL. IMPDH Inhibition Decreases TERT Expression and Synergizes the Cytotoxic Effect of Chemotherapeutic Agents in Glioblastoma Cells. Int J Mol Sci 2024; 25:5992. [PMID: 38892179 PMCID: PMC11172490 DOI: 10.3390/ijms25115992] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2024] [Revised: 05/21/2024] [Accepted: 05/28/2024] [Indexed: 06/21/2024] Open
Abstract
IMP dehydrogenase (IMPDH) inhibition has emerged as a new target therapy for glioblastoma multiforme (GBM), which remains one of the most refractory tumors to date. TCGA analyses revealed distinct expression profiles of IMPDH isoenzymes in various subtypes of GBM and low-grade glioma (LGG). To dissect the mechanism(s) underlying the anti-tumor effect of IMPDH inhibition in adult GBM, we investigated how mycophenolic acid (MPA, an IMPDH inhibitor) treatment affected key oncogenic drivers in glioblastoma cells. Our results showed that MPA decreased the expression of telomerase reverse transcriptase (TERT) in both U87 and U251 cells, and the expression of O6-methylguanine-DNA methyltransferase (MGMT) in U251 cells. In support, MPA treatment reduced the amount of telomere repeats in U87 and U251 cells. TERT downregulation by MPA was associated with a significant decrease in c-Myc (a TERT transcription activator) in U87 but not U251 cells, and a dose-dependent increase in p53 and CCCTC-binding factor (CTCF) (TERT repressors) in both U87 and U251 cells. In U251 cells, MPA displayed strong cytotoxic synergy with BCNU and moderate synergy with irinotecan, oxaliplatin, paclitaxel, or temozolomide (TMZ). In U87 cells, MPA displayed strong cytotoxic synergy with all except TMZ, acting primarily through the apoptotic pathway. Our work expands the mechanistic potential of IMPDH inhibition to TERT/telomere regulation and reveals a synthetic lethality between MPA and anti-GBM drugs.
Collapse
Affiliation(s)
- Xiaoqin Liu
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX 77030, USA; (X.L.); (J.W.); (L.J.W.); (B.T.)
| | - Junying Wang
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX 77030, USA; (X.L.); (J.W.); (L.J.W.); (B.T.)
| | - Laura J. Wu
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX 77030, USA; (X.L.); (J.W.); (L.J.W.); (B.T.)
| | - Britni Trinh
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX 77030, USA; (X.L.); (J.W.); (L.J.W.); (B.T.)
| | - Robert Y. L. Tsai
- Institute of Biosciences and Technology, Texas A&M University Health Science Center, Houston, TX 77030, USA; (X.L.); (J.W.); (L.J.W.); (B.T.)
- Department of Translational Medical Sciences, College of Medicine, Texas A&M University Health Science Center, Houston, TX 77030, USA
| |
Collapse
|
6
|
Yap TA, Tolcher AW, Plummer R, Mukker JK, Enderlin M, Hicking C, Grombacher T, Locatelli G, Szucs Z, Gounaris I, de Bono JS. First-in-Human Study of the Ataxia Telangiectasia and Rad3-Related (ATR) Inhibitor Tuvusertib (M1774) as Monotherapy in Patients with Solid Tumors. Clin Cancer Res 2024; 30:2057-2067. [PMID: 38407317 PMCID: PMC11094421 DOI: 10.1158/1078-0432.ccr-23-2409] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/26/2023] [Accepted: 02/21/2024] [Indexed: 02/27/2024]
Abstract
PURPOSE Tuvusertib (M1774) is a potent, selective, orally administered ataxia telangiectasia and Rad3-related (ATR) protein kinase inhibitor. This first-in-human study (NCT04170153) evaluated safety, tolerability, maximum tolerated dose (MTD), recommended dose for expansion (RDE), pharmacokinetics (PK), pharmacodynamics (PD), and preliminary efficacy of tuvusertib monotherapy. PATIENTS AND METHODS Ascending tuvusertib doses were evaluated in 55 patients with metastatic or locally advanced unresectable solid tumors. A safety monitoring committee determined dose escalation based on PK, PD, and safety data guided by a Bayesian 2-parameter logistic regression model. Molecular responses (MR) were assessed in circulating tumor DNA samples. RESULTS Most common grade ≥3 treatment-emergent adverse events were anemia (36%), neutropenia, and lymphopenia (both 7%). Eleven patients experienced dose-limiting toxicities, most commonly grade 2 (n = 2) or 3 (n = 8) anemia. No persistent effects on blood immune cell populations were observed. The RDE was 180 mg tuvusertib QD (once daily), 2 weeks on/1 week off treatment, which was better tolerated than the MTD (180 mg QD continuously). Tuvusertib median time to peak plasma concentration ranged from 0.5 to 3.5 hours and mean elimination half-life from 1.2 to 5.6 hours. Exposure-related PD analysis suggested maximum target engagement at ≥130 mg tuvusertib QD. Tuvusertib induced frequent MRs in the predicted efficacious dose range; MRs were enriched in patients with radiological disease stabilization, and complete MRs were detected for mutations in ARID1A, ATRX, and DAXX. One patient with platinum- and PARP inhibitor-resistant BRCA wild-type ovarian cancer achieved an unconfirmed RECIST v1.1 partial response. CONCLUSIONS Tuvusertib demonstrated manageable safety and exposure-related target engagement. Further clinical evaluation of tuvusertib is ongoing.
Collapse
Affiliation(s)
- Timothy A. Yap
- University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Ruth Plummer
- Newcastle University and Northern Centre for Cancer Care, Newcastle Hospitals NHS Trust, Newcastle Upon Tyne, United Kingdom
| | | | - Marta Enderlin
- The Healthcare Business of Merck KGaA, Darmstadt, Germany
| | | | | | | | - Zoltan Szucs
- Merck Serono Ltd., Feltham, UK, an affiliate of Merck KGaA, Darmstadt, Germany
| | - Ioannis Gounaris
- Merck Serono Ltd., Feltham, UK, an affiliate of Merck KGaA, Darmstadt, Germany
| | | |
Collapse
|
7
|
Alcock LJ, Sudhakar HK, Young R, Lau YH. Fluorescence polarization assay for screening FANCM-RMI inhibitors to target the alternative lengthening of telomeres. Methods Enzymol 2024; 698:361-378. [PMID: 38886039 DOI: 10.1016/bs.mie.2024.04.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Alternative Lengthening of Telomeres (ALT) is a mechanism used by 10-15% of all cancers to achieve replicative immortality, bypassing the DNA damage checkpoint associated with short telomeres that leads to cellular senescence or apoptosis. ALT does not occur in non-cancerous cells, presenting a potential therapeutic window for cancers where this mechanism is active. Disrupting the FANCM-RMI interaction has emerged as a promising therapeutic strategy that induces synthetic ALT lethality in genetic studies on cancer cell lines. There are currently no chemical inhibitors reported in the literature, in part due to the lack of reliable biophysical or biochemical assays to screen for FANCM-RMI disruption. Here we describe the development of a robust competitive fluorescence polarization (FP) assay that quantifies target binding at the FANCM-RMI interface. The assay employs a labeled peptide tracer TMR-RaMM2 derived from the native MM2 binding motif, which binds to recombinant RMI1-RMI2 and can be displaced by competitive inhibitors. We report the methods for recombinant production of RMI1-RMI2, design and evaluation of the tracer TMR-RaMM2, along with unlabeled peptide inhibitor controls to enable ALT-targeted drug discovery.
Collapse
Affiliation(s)
- Lisa J Alcock
- School of Chemistry, The University of Sydney, Camperdown, NSW, Australia.
| | | | - Reginald Young
- School of Chemistry, The University of Sydney, Camperdown, NSW, Australia
| | - Yu Heng Lau
- School of Chemistry, The University of Sydney, Camperdown, NSW, Australia.
| |
Collapse
|
8
|
Burris HA, Berlin J, Arkenau T, Cote GM, Lolkema MP, Ferrer-Playan J, Kalapur A, Bolleddula J, Locatelli G, Goddemeier T, Gounaris I, de Bono J. A phase I study of ATR inhibitor gartisertib (M4344) as a single agent and in combination with carboplatin in patients with advanced solid tumours. Br J Cancer 2024; 130:1131-1140. [PMID: 38287179 PMCID: PMC10991509 DOI: 10.1038/s41416-023-02436-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 08/31/2023] [Accepted: 09/11/2023] [Indexed: 01/31/2024] Open
Abstract
BACKGROUND Gartisertib is an oral inhibitor of ataxia telangiectasia and Rad3-related protein (ATR), a key kinase of the DNA damage response. We aimed to determine the safety and tolerability of gartisertib ± carboplatin in patients with advanced solid tumours. METHODS This phase I open-label, multicenter, first-in-human study comprised four gartisertib cohorts: A (dose escalation [DE]; Q2W); A2 (DE; QD/BID); B1 (DE+carboplatin); and C (biomarker-selected patients). RESULTS Overall, 97 patients were enroled into cohorts A (n = 42), A2 (n = 26), B1 (n = 16) and C (n = 13). The maximum tolerated dose and recommended phase II dose (RP2D) were not declared for cohorts A or B1. In cohort A2, the RP2D for gartisertib was determined as 250 mg QD. Gartisertib was generally well-tolerated; however, unexpected increased blood bilirubin in all study cohorts precluded further DE. Investigations showed that gartisertib and its metabolite M26 inhibit UGT1A1-mediated bilirubin glucuronidation in human but not dog or rat liver microsomes. Prolonged partial response (n = 1 [cohort B1]) and stable disease >6 months (n = 3) did not appear to be associated with biomarker status. Exposure generally increased dose-dependently without accumulation. CONCLUSION Gartisertib was generally well-tolerated at lower doses; however, unexpected liver toxicity prevented further DE, potentially limiting antitumour activity. Gartisertib development was subsequently discontinued. CLINICALTRIALS GOV: NCT02278250.
Collapse
Affiliation(s)
| | - Jordan Berlin
- Division of Hematology/Oncology, Vanderbilt-Ingram Cancer Center, Nashville, TN, USA
| | | | - Gregory M Cote
- Division of Hematology and Oncology, Mass General Cancer Center, Boston, MA, USA
| | - Martijn P Lolkema
- Department of Medical Oncology, Erasmus MC Cancer Institute, Utrecht, Netherlands
- Amgen Inc., Thousand Oaks, CA, USA
| | - Jordi Ferrer-Playan
- Global Clinical Development, Ares Trading SA, an affiliate of Merck KGaA, Eysins, Switzerland
| | - Anup Kalapur
- Global Patient Safety Oncology, Merck Healthcare KGaA, Darmstadt, Germany
| | - Jayaprakasam Bolleddula
- Quantitative Pharmacology, EMD Serono Research & Development Institute, Inc., an affiliate of Merck KGaA, Billerica, MA, USA
| | | | | | - Ioannis Gounaris
- Global Clinical Development, Merck Serono Ltd., an affiliate of Merck KGaA, Feltham, UK
| | - Johann de Bono
- Division of Clinical Studies, Institute of Cancer Research, London, UK
- Royal Marsden, Hospital, London, UK
| |
Collapse
|
9
|
Das A, Giri AK, Bhattacharjee P. Targeting 'histone mark': Advanced approaches in epigenetic regulation of telomere dynamics in cancer. BIOCHIMICA ET BIOPHYSICA ACTA. GENE REGULATORY MECHANISMS 2024; 1867:195007. [PMID: 38237857 DOI: 10.1016/j.bbagrm.2024.195007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 01/09/2024] [Accepted: 01/10/2024] [Indexed: 01/23/2024]
Abstract
Telomere integrity is required for the maintenance of genome stability and prevention of oncogenic transformation of cells. Recent evidence suggests the presence of epigenetic modifications as an important regulator of mammalian telomeres. Telomeric and subtelomeric regions are rich in epigenetic marks that regulate telomere length majorly through DNA methylation and post-translational histone modifications. Specific histone modifying enzymes play an integral role in establishing telomeric histone codes necessary for the maintenance of structural integrity. Alterations of crucial histone moieties and histone modifiers cause deregulations in the telomeric chromatin leading to carcinogenic manifestations. This review delves into the significance of histone modifications and their influence on telomere dynamics concerning cancer. Additionally, it highlights the existing research gaps that hold the potential to drive the development of therapeutic interventions targeting the telomere epigenome.
Collapse
Affiliation(s)
- Ankita Das
- Department of Environmental Science, University of Calcutta, Kolkata 700019, India; Department of Zoology, University of Calcutta, Kolkata 700019, India
| | - Ashok K Giri
- Molecular Genetics Division, CSIR-Indian Institute of Chemical Biology, Kolkata 700032, India
| | - Pritha Bhattacharjee
- Department of Environmental Science, University of Calcutta, Kolkata 700019, India.
| |
Collapse
|
10
|
Thosar SA, Barnes RP, Detwiler A, Bhargava R, Wondisford A, O'Sullivan RJ, Opresko PL. Oxidative guanine base damage plays a dual role in regulating productive ALT-associated homology-directed repair. Cell Rep 2024; 43:113656. [PMID: 38194346 PMCID: PMC10851105 DOI: 10.1016/j.celrep.2023.113656] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 11/06/2023] [Accepted: 12/20/2023] [Indexed: 01/10/2024] Open
Abstract
Cancer cells maintain telomeres by upregulating telomerase or alternative lengthening of telomeres (ALT) via homology-directed repair at telomeric DNA breaks. 8-Oxoguanine (8oxoG) is a highly prevalent endogenous DNA lesion in telomeric sequences, altering telomere structure and telomerase activity, but its impact on ALT is unclear. Here, we demonstrate that targeted 8oxoG formation at telomeres stimulates ALT activity and homologous recombination specifically in ALT cancer cells. Mechanistically, an acute 8oxoG induction increases replication stress, as evidenced by increased telomere fragility and ATR kinase activation at ALT telomeres. Furthermore, ALT cells are more sensitive to chronic telomeric 8oxoG damage than telomerase-positive cancer cells, consistent with increased 8oxoG-induced replication stress. However, telomeric 8oxoG production in G2 phase, when ALT telomere elongation occurs, impairs telomeric DNA synthesis. Our study demonstrates that a common oxidative base lesion has a dual role in regulating ALT depending on when the damage arises in the cell cycle.
Collapse
Affiliation(s)
- Sanjana A Thosar
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA; UPMC Hillman Cancer Center, Pittsburgh, PA, USA
| | - Ryan P Barnes
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA; UPMC Hillman Cancer Center, Pittsburgh, PA, USA
| | - Ariana Detwiler
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA; UPMC Hillman Cancer Center, Pittsburgh, PA, USA
| | - Ragini Bhargava
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Anne Wondisford
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Roderick J O'Sullivan
- UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Patricia L Opresko
- Department of Environmental and Occupational Health, University of Pittsburgh School of Public Health, Pittsburgh, PA, USA; UPMC Hillman Cancer Center, Pittsburgh, PA, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| |
Collapse
|
11
|
Lu R, Nelson CB, Rogers S, Cesare AJ, Sobinoff AP, Pickett HA. Distinct modes of telomere synthesis and extension contribute to Alternative Lengthening of Telomeres. iScience 2024; 27:108655. [PMID: 38213617 PMCID: PMC10783591 DOI: 10.1016/j.isci.2023.108655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/13/2023] [Accepted: 12/04/2023] [Indexed: 01/13/2024] Open
Abstract
Alternative lengthening of telomeres (ALT) is a homology-directed repair mechanism that becomes activated in a subset of cancers to maintain telomere length. One of the defining features of ALT cells is the prevalence of extrachromosomal telomeric repeat (ECTR) DNA. Here, we identify that ALT cells engage in two modes of telomere synthesis. Non-productive telomere synthesis occurs during the G2 phase of the cell cycle and is characterized by newly synthesized internal telomeric regions that are not retained in the subsequent G1, coinciding with an induction of ECTR DNA. Productive telomere synthesis occurs specifically during the transition from G2 to mitosis and is defined as the extension of the telomere termini. While many proteins associated with break-induced telomere synthesis function in both non-productive and productive telomere synthesis, POLH specifically promotes productive telomere lengthening and suppresses non-productive telomere synthesis. These findings delineate the mechanism and cell cycle regulation of ALT-mediated telomere synthesis and extension.
Collapse
Affiliation(s)
- Robert Lu
- Telomere Length Regulation Unit, Children’s Medical Research Institute, University of Sydney, Westmead, NSW, Australia
| | - Christopher B. Nelson
- Telomere Length Regulation Unit, Children’s Medical Research Institute, University of Sydney, Westmead, NSW, Australia
| | - Samuel Rogers
- Genome Integrity Unit, Children’s Medical Research Institute, University of Sydney, Westmead, NSW, Australia
| | - Anthony J. Cesare
- Genome Integrity Unit, Children’s Medical Research Institute, University of Sydney, Westmead, NSW, Australia
| | - Alexander P. Sobinoff
- Telomere Length Regulation Unit, Children’s Medical Research Institute, University of Sydney, Westmead, NSW, Australia
| | - Hilda A. Pickett
- Telomere Length Regulation Unit, Children’s Medical Research Institute, University of Sydney, Westmead, NSW, Australia
| |
Collapse
|
12
|
Mori JO, Keegan J, Flynn RL, Heaphy CM. Alternative lengthening of telomeres: mechanism and the pathogenesis of cancer. J Clin Pathol 2024; 77:82-86. [PMID: 37890990 DOI: 10.1136/jcp-2023-209005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Accepted: 10/12/2023] [Indexed: 10/29/2023]
Abstract
Telomere maintenance and elongation allows cells to gain replicative immortality and evade cellular senescence during cancer development. While most cancers use telomerase to maintain telomere lengths, a subset of cancers engage the alternative lengthening of telomeres (ALT) pathway for telomere maintenance. ALT is present in 5%-10% of all cancers, although the prevalence is dramatically higher in certain cancer types, including complex karyotype sarcomas, isocitrate dehydrogenase-mutant astrocytoma (WHO grade II-IV), pancreatic neuroendocrine tumours, neuroblastoma and chromophobe hepatocellular carcinomas. ALT is maintained through a homology-directed DNA repair mechanism. Resembling break-induced replication, this aberrant process results in dramatic cell-to-cell telomere length heterogeneity, widespread chromosomal instability and chronic replication stress. Additionally, ALT-positive cancers frequently harbour inactivating mutations in either chromatin remodelling proteins (ATRX, DAXX and H3F3A) or DNA damage repair factors (SMARCAL1 and SLX4IP). ALT can readily be detected in tissue by assessing the presence of unique molecular characteristics, such as large ultrabright nuclear telomeric foci or partially single-stranded telomeric DNA circles (C-circles). Importantly, ALT has been validated as a robust diagnostic and prognostic biomarker for certain cancer types and may even be exploited as a therapeutic target via small molecular inhibitors and/or synthetic lethality approaches.
Collapse
Affiliation(s)
- Joakin O Mori
- Medicine, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Joshua Keegan
- Pharmacology, Physiology & Biophysics, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Rachel L Flynn
- Medicine, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
- Pharmacology, Physiology & Biophysics, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
| | - Christopher M Heaphy
- Medicine, Boston University Chobanian & Avedisian School of Medicine, Boston, Massachusetts, USA
- Pathology and Laboratory Medicine, Boston Medical Center, Boston, Massachusetts, USA
| |
Collapse
|
13
|
Lulla RR, Buxton A, Krailo MD, Lazow MA, Boue DR, Leach JL, Lin T, Geller JI, Kumar SS, Nikiforova MN, Chandran U, Jogal SS, Nelson MD, Onar-Thomas A, Haas-Kogan DA, Cohen KJ, Kieran MW, Gajjar A, Drissi R, Pollack IF, Fouladi M. Vorinostat, temozolomide or bevacizumab with irradiation and maintenance BEV/TMZ in pediatric high-grade glioma: A Children's Oncology Group Study. Neurooncol Adv 2024; 6:vdae035. [PMID: 38596718 PMCID: PMC11003537 DOI: 10.1093/noajnl/vdae035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024] Open
Abstract
Background Outcomes for children with high-grade gliomas (HGG) remain poor. This multicenter phase II trial evaluated whether concurrent use of vorinostat or bevacizumab with focal radiotherapy (RT) improved 1-year event-free survival (EFS) compared to temozolomide in children with newly diagnosed HGG who received maintenance temozolomide and bevacizumab. Methods Patients ≥ 3 and < 22 years with localized, non-brainstem HGG were randomized to receive RT (dose 54-59.4Gy) with vorinostat, temozolomide, or bevacizumab followed by 12 cycles of bevacizumab and temozolomide maintenance therapy. Results Among 90 patients randomized, the 1-year EFS for concurrent bevacizumab, vorinostat, or temozolomide with RT was 43.8% (±8.8%), 41.4% (±9.2%), and 59.3% (±9.5%), respectively, with no significant difference among treatment arms. Three- and five-year EFS for the entire cohort was 14.8% and 13.4%, respectively, with no significant EFS difference among the chemoradiotherapy arms. IDH mutations were associated with more favorable EFS (P = .03), whereas H3.3 K27M mutations (P = .0045) and alterations in PIK3CA or PTEN (P = .025) were associated with worse outcomes. Patients with telomerase- and alternative lengthening of telomeres (ALT)-negative tumors (n = 4) had an EFS of 100%, significantly greater than those with ALT or telomerase, or both (P = .002). While there was no difference in outcomes based on TERT expression, high TERC expression was associated with inferior survival independent of the telomere maintenance mechanism (P = .0012). Conclusions Chemoradiotherapy with vorinostat or bevacizumab is not superior to temozolomide in children with newly diagnosed HGG. Patients with telomerase- and ALT-negative tumors had higher EFS suggesting that, if reproduced, mechanism of telomere maintenance should be considered in molecular-risk stratification in future studies.
Collapse
Affiliation(s)
- Rishi R Lulla
- Department of Pediatrics, Hasbro Children’s Hospital, The Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA
| | - Allen Buxton
- Department of Biostatistics, Children’s Oncology Group, Monrovia, California, USA
| | - Mark D Krailo
- Department of Biostatistics, Children’s Oncology Group, Monrovia, California, USA
| | - Margot A Lazow
- Pediatric Neuro‑Oncology Program, Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Daniel R Boue
- Department of Pathology and Laboratory Medicine, Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - James L Leach
- Department of Radiology and Medical Imaging, Cincinnati Children’s Hospital Medical Center, Department of Radiology, University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | - Tong Lin
- Department of Biostatistics, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - James I Geller
- Division of Oncology, Cincinnati Children’s Hospital Medical Center, University of Cincinnati, Cincinnati, Ohio, USA
| | - Shiva Senthil Kumar
- Center for Childhood Cancer Research, Nationwide Children’s Hospital, Columbus, Ohio, USA
| | - Marina N Nikiforova
- Division of Molecular & Genomic Pathology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, USA
| | - Uma Chandran
- Department of Biomedical Informatics, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Sachin S Jogal
- Department of Pediatrics, Medical College of Wisconsin, Milwaukee, Wisconsin, USA
| | - Marvin D Nelson
- Department of Radiology, Children’s Hospital Los Angeles, Keck University of Southern California School of Medicine, Los Angeles, California, USA
| | - Arzu Onar-Thomas
- Department of Biostatistics, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Daphne A Haas-Kogan
- Department of Radiation Oncology, Brigham and Women’s Hospital, Boston Children’s Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Kenneth J Cohen
- Division of Pediatric Oncology, Department of Pediatrics, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Mark W Kieran
- Department of Pediatric Oncology, Dana-Farber/Boston Children’s Cancer and Blood Disorders Center, Harvard Medical School, Boston, Massachusetts, USA
| | - Amar Gajjar
- Department of Pediatric Medicine, St Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - Rachid Drissi
- Center for Childhood Cancer Research, Nationwide Children’s Hospital, Columbus, OH, The Ohio State University College of Medicine, Columbus, Ohio, USA
| | - Ian F Pollack
- Department of Neurosurgery, UPMC Children’s Hospital of Pittsburgh, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Maryam Fouladi
- Pediatric Neuro‑Oncology Program, Nationwide Children’s Hospital, The Ohio State University College of Medicine, Columbus, Ohio, USA
| |
Collapse
|
14
|
Rosso I, Jones-Weinert C, Rossiello F, Cabrini M, Brambillasca S, Munoz-Sagredo L, Lavagnino Z, Martini E, Tedone E, Garre' M, Aguado J, Parazzoli D, Mione M, Shay JW, Mercurio C, d'Adda di Fagagna F. Alternative lengthening of telomeres (ALT) cells viability is dependent on C-rich telomeric RNAs. Nat Commun 2023; 14:7086. [PMID: 37925537 PMCID: PMC10625592 DOI: 10.1038/s41467-023-42831-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 10/23/2023] [Indexed: 11/06/2023] Open
Abstract
Alternative lengthening of telomeres (ALT) is a telomere maintenance mechanism activated in ~10-15% of cancers, characterized by telomeric damage. Telomeric damage-induced long non-coding RNAs (dilncRNAs) are transcribed at dysfunctional telomeres and contribute to telomeric DNA damage response (DDR) activation and repair. Here we observed that telomeric dilncRNAs are preferentially elevated in ALT cells. Inhibition of C-rich (teloC) dilncRNAs with antisense oligonucleotides leads to DNA replication stress responses, increased genomic instability, and apoptosis induction selectively in ALT cells. Cell death is dependent on DNA replication and is increased by DNA replication stress. Mechanistically, teloC dilncRNA inhibition reduces RAD51 and 53BP1 recruitment to telomeres, boosts the engagement of BIR machinery, and increases C-circles and telomeric sister chromatid exchanges, without increasing telomeric non-S phase synthesis. These results indicate that teloC dilncRNA is necessary for a coordinated recruitment of DDR factors to ALT telomeres and it is essential for ALT cancer cells survival.
Collapse
Affiliation(s)
- Ilaria Rosso
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Corey Jones-Weinert
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
- The Salk Institute for Biological Studies, La Jolla, CA, USA
| | | | - Matteo Cabrini
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Silvia Brambillasca
- IFOM ETS - The AIRC Institute of Molecular Oncology (Experimental Therapeutics Program), Milan, Italy
| | - Leonel Munoz-Sagredo
- Institute of Biological and Chemical Systems - Functional Molecular Systems (IBCS-FMS), Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
- School of Medicine, Universidad de Valparaiso, Valparaiso, Chile
| | - Zeno Lavagnino
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Emanuele Martini
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
- Dipartimento di Oncologia ed Emato-Oncologia, Università degli Studi di Milano, Milan, Italy
| | - Enzo Tedone
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Massimiliano Garre'
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
- RCSI, Royal College of Surgeons in Ireland, Department of Chemistry, Dublin, Ireland
| | - Julio Aguado
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
- Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, QLD, Australia
| | - Dario Parazzoli
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy
| | - Marina Mione
- Department of Cellular, Computational and Integrative Biology - CIBIO, University of Trento, Trento, Italy
| | - Jerry W Shay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Ciro Mercurio
- IFOM ETS - The AIRC Institute of Molecular Oncology (Experimental Therapeutics Program), Milan, Italy
| | - Fabrizio d'Adda di Fagagna
- IFOM ETS - The AIRC Institute of Molecular Oncology, Milan, Italy.
- Institute of Molecular Genetics IGM-CNR "Luigi Luca Cavalli-Sforza", Pavia, Italy.
| |
Collapse
|
15
|
Cai Y, Guo H, Zhou J, Zhu G, Qu H, Liu L, Shi T, Ge S, Qu Y. An alternative extension of telomeres related prognostic model to predict survival in lower grade glioma. J Cancer Res Clin Oncol 2023; 149:13575-13589. [PMID: 37515613 DOI: 10.1007/s00432-023-05155-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 07/09/2023] [Indexed: 07/31/2023]
Abstract
OBJECTIVE The alternative extension of the telomeres (ALT) mechanism is activated in lower grade glioma (LGG), but the role of the ALT mechanism has not been well discussed. The primary purpose was to demonstrate the significance of the ALT mechanism in prognosis estimation for LGG patients. METHOD Gene expression and clinical data of LGG patients were collected from the Chinese Glioma Genome Atlas (CGGA) and the Cancer Genome Atlas (TCGA) cohort, respectively. ALT-related genes obtained from the TelNet database and potential prognostic genes related to ALT were selected by LASSO regression to calculate an ALT-related risk score. Multivariate Cox regression analysis was performed to construct a prognosis signature, and a nomogram was used to represent this signature. Possible pathways of the ALT-related risk score are explored by enrichment analysis. RESULT The ALT-related risk score was calculated based on the LASSO regression coefficients of 22 genes and then divided into high-risk and low-risk groups according to the median. The ALT-related risk score is an independent predictor of LGG (HR and 95% CI in CGGA cohort: 5.70 (3.79, 8.58); in TCGA cohort: 1.96 (1.09, 3.54)). ROC analysis indicated that the model contained ALT-related risk score was superior to conventional clinical features (AUC: 0.818 vs 0.729) in CGGA cohorts. The results in the TCGA cohort also shown a powerful ability of ALT-related risk score (AUC: 0.766 vs 0.691). The predicted probability and actual probability of the nomogram are consistent. Enrichment analysis demonstrated that the ALT mechanism was involved in the cell cycle, DNA repair, immune processes, and others. CONCLUSION ALT-related risk score based on the 22-gene is an important factor in predicting the prognosis of LGG patients.
Collapse
Affiliation(s)
- Yaning Cai
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China
| | - Hao Guo
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China
| | - JinPeng Zhou
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China
| | - Gang Zhu
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China
| | - Hongwen Qu
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China
| | - Lingyu Liu
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China
| | - Tao Shi
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China
| | - Shunnan Ge
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China.
| | - Yan Qu
- Department of Neurosurgery, Tangdu Hospital, Fourth Military Medical University, No. 569 Xinsi Road, Xi'an 710038, China.
| |
Collapse
|
16
|
Nasioudis D, Latif NA, Ko EM, Cory L, Kim SH, Martin L, Simpkins F, Giuntoli R. Next generation sequencing reveals a high prevalence of pathogenic mutations in homologous recombination DNA damage repair genes among patients with uterine sarcoma. Gynecol Oncol 2023; 177:14-19. [PMID: 37611378 DOI: 10.1016/j.ygyno.2023.07.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2023] [Revised: 07/29/2023] [Accepted: 07/31/2023] [Indexed: 08/25/2023]
Abstract
OBJECTIVE Investigate the incidence of homologous recombination DNA damage response (HR-DDR) genomic alterations among patients with uterine sarcoma. METHODS The American Association for Cancer Research GENIE v13.0 database was accessed and patients with uterine leiomyosarcoma, adenosarcoma, undifferentiated uterine sarcoma, high-grade endometrial stromal sarcoma, low-grade endometrial stromal sarcoma, and endometrial stromal sarcoma not otherwise specified were identified. We determined the incidence of pathogenic alterations in the following genes involved in HR-DDR: ATM, ARID1A, ATRX, BAP1, BARD1, BLM, BRCA2, BRCA1, BRIP1, CHEK2, CHEK1, FANCA, FANCC, FANCD2, FANCE, FANCF, FANCG, FANCL, MRE11, NBN, PALB2, RAD50, RAD51, RAD51B, RAD51C, RAD51D, WRN. Data from the OncoKB database, as provided by cBioPortal, was utilized to determine the presence of pathogenic genomic alterations. RESULTS A total of 509 patients contributing with 525 samples were identified. Median patient age at sample collection was 56 years while the majority were White (80.7%). The most common histologic subtype was leiomyosarcoma (63.8%) followed by adenosarcoma (12.3%). The overall incidence of HR-DDR genomic alterations was 28.2%. The most commonly altered genes were ATRX (18.2%), BRCA2 (4%), and RAD51B (2.6%). The highest incidence of HR-DDR genomic alterations was observed among patients with leiomyosarcoma (35.4%), adenosarcoma (27%) and undifferentiated uterine sarcoma (30%), while those with low-grade endometrial stromal sarcoma had the lowest (2.9%) incidence. CONCLUSIONS Approximately 1 in 3 patients with uterine sarcoma harbor a pathogenic alteration in HR-DDR genes. Incidence is high among patients with uterine leiomyosarcoma and adenosarcoma.
Collapse
Affiliation(s)
- Dimitrios Nasioudis
- Division of Gynecologic Oncology, University of Pennsylvania Health System, Philadelphia, PA, USA.
| | - Nawar A Latif
- Division of Gynecologic Oncology, University of Pennsylvania Health System, Philadelphia, PA, USA
| | - Emily M Ko
- Division of Gynecologic Oncology, University of Pennsylvania Health System, Philadelphia, PA, USA
| | - Lori Cory
- Division of Gynecologic Oncology, University of Pennsylvania Health System, Philadelphia, PA, USA
| | - Sarah H Kim
- Division of Gynecologic Oncology, University of Pennsylvania Health System, Philadelphia, PA, USA
| | - Lainie Martin
- Division of Gynecologic Oncology, University of Pennsylvania Health System, Philadelphia, PA, USA
| | - Fiona Simpkins
- Division of Gynecologic Oncology, University of Pennsylvania Health System, Philadelphia, PA, USA
| | - Robert Giuntoli
- Division of Gynecologic Oncology, University of Pennsylvania Health System, Philadelphia, PA, USA
| |
Collapse
|
17
|
Ali JH, Walter M. Combining old and new concepts in targeting telomerase for cancer therapy: transient, immediate, complete and combinatory attack (TICCA). Cancer Cell Int 2023; 23:197. [PMID: 37679807 PMCID: PMC10483736 DOI: 10.1186/s12935-023-03041-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2023] [Accepted: 08/25/2023] [Indexed: 09/09/2023] Open
Abstract
Telomerase can overcome replicative senescence by elongation of telomeres but is also a specific element in most cancer cells. It is expressed more vastly than any other tumor marker. Telomerase as a tumor target inducing replicative immortality can be overcome by only one other mechanism: alternative lengthening of telomeres (ALT). This limits the probability to develop resistance to treatments. Moreover, telomerase inhibition offers some degree of specificity with a low risk of toxicity in normal cells. Nevertheless, only one telomerase antagonist reached late preclinical studies. The underlying causes, the pitfalls of telomerase-based therapies, and future chances based on recent technical advancements are summarized in this review. Based on new findings and approaches, we propose a concept how long-term survival in telomerase-based cancer therapies can be significantly improved: the TICCA (Transient Immediate Complete and Combinatory Attack) strategy.
Collapse
Affiliation(s)
- Jaber Haj Ali
- Institute of Laboratory Medicine, Clinical Chemistry and Pathobiochemistry, Charité Universitätsmedizin Berlin, Augustenburger Platz 1, 13353, Berlin, Germany
- Institute of Clinical Chemistry and Laboratory Medicine, Universitätsmedizin Rostock, Ernst-Heydemann-Straße 6, 18057, Rostock, Germany
| | - Michael Walter
- Institute of Clinical Chemistry and Laboratory Medicine, Universitätsmedizin Rostock, Ernst-Heydemann-Straße 6, 18057, Rostock, Germany.
| |
Collapse
|
18
|
Kreilmeier-Berger T, Aupperle-Lellbach H, Reifinger M, Hörstke NV, Holzmann K, Kleiter M. Alternative Lengthening of Telomeres Is Rare in Canine Histiocytic Sarcoma. Cancers (Basel) 2023; 15:4214. [PMID: 37686490 PMCID: PMC10487132 DOI: 10.3390/cancers15174214] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 08/19/2023] [Accepted: 08/20/2023] [Indexed: 09/10/2023] Open
Abstract
Cancer cells activate telomere maintenance mechanisms (TMMs) to overcome senescence and thus are targets for TMM-specific therapies. Telomerase-independent alternative lengthening of telomeres (ALT) is frequently utilized as a TMM in human sarcoma subtypes. Histiocytic sarcoma (HS) is a rare but aggressive tumor of hematopoietic origin with unknown ALT incidence in humans. ALT has been identified in canine HS, a tumor type comparable to human HS that occurs with high rates in certain canine breeds such as Bernese mountain dogs (BMDs). This retrospective study characterized the frequency of ALT in BMD and non-BMD patients diagnosed with HS as surrogates for humans. Formalin-fixed paraffin-embedded tumor samples from 63 dogs at two centers, including 47 BMDs, were evaluated for their ALT activity and relative telomere content (TC) using a radiolabel C-circle assay (CCA). Known ALT-positive samples served as controls. CCA-positive cases were validated via FISH. Two BMD samples showed ALT activity of 1-14% compared to controls. All other samples were ALT-negative. The TC did not correlate with the CCA results. ALT positivity was validated by the appearance of ultrabright telomere foci. Low ALT activity was present in 4% of BMDs with HS and therefore does not appear to be a common target for therapeutic approaches but can have diagnostic value.
Collapse
Affiliation(s)
- Theresa Kreilmeier-Berger
- Department for Companion Animals and Horses, University of Veterinary Medicine, 1210 Vienna, Austria;
| | | | - Martin Reifinger
- Department of Pathobiology, University of Veterinary Medicine, 1210 Vienna, Austria;
| | - Nicolai Valentin Hörstke
- Center for Cancer Research, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria;
| | - Klaus Holzmann
- Center for Cancer Research, Comprehensive Cancer Center, Medical University of Vienna, 1090 Vienna, Austria;
| | - Miriam Kleiter
- Department for Companion Animals and Horses, University of Veterinary Medicine, 1210 Vienna, Austria;
| |
Collapse
|
19
|
van Ipenburg JA, van den Bosch QCC, Paridaens D, Dubbink HJ, Kiliç E, Naus N, Verdijk RM. ATRX Loss in the Development and Prognosis of Conjunctival Melanoma. Int J Mol Sci 2023; 24:12988. [PMID: 37629169 PMCID: PMC10454703 DOI: 10.3390/ijms241612988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 08/08/2023] [Accepted: 08/18/2023] [Indexed: 08/27/2023] Open
Abstract
Metastatic disease is linked to TERT promoter mutations in conjunctival melanomas (CM). Both TERT promoter and ATRX mutations are associated with faulty telomere maintenance. This study aimed to determine the prognostic value of ATRX loss in conjunctival melanocytic lesions. Eighty-six conjunctival melanocytic lesions from the Rotterdam Ocular Melanoma Study group were collected. ATRX status and TERT promoter status were determined using immunohistochemical staining and molecular diagnostics, respectively. None of the nevi (n = 16) and primary acquired melanosis (PAM) without atypia (n = 6) showed ATRX loss. ATRX loss was found in 2/5 PAM with atypia without CM and in 8/59 CM. No cases with a TERT promoter mutation (n = 26) showed ATRX loss. Eight/eleven metastatic CM harbored a TERT promoter mutation, two other metastatic CM showed ATRX loss and one metastatic case showed no TERT promoter/ATRX alterations. In conclusion ATRX loss and TERT promoter mutations are only found in (pre)malignant conjunctival melanocytic lesions, with most metastatic cases harboring one of these alterations, suggesting that both alterations are associated with adverse behavior. Similar to TERT promoter mutations, ATRX loss may be used as a diagnostic tool in determining whether a conjunctival melanocytic lesion is prone to having an adverse course.
Collapse
Affiliation(s)
- Jolique A. van Ipenburg
- Department of Pathology, Radboud University Medical Center, Geert Grooteplein Zuid 10, 6525 GA Nijmegen, The Netherlands
| | - Quincy C. C. van den Bosch
- Department of Ophthalmology, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Dion Paridaens
- Department of Ophthalmology, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
- Department of Ocular Oncology, The Rotterdam Eye Hospital, Schiedamse Vest 180, 3011 BH Rotterdam, The Netherlands
| | - Hendrikus J. Dubbink
- Department of Pathology, Section Ophthalmic Pathology, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Emine Kiliç
- Department of Ophthalmology, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Nicole Naus
- Department of Ophthalmology, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
| | - Robert M. Verdijk
- Department of Ocular Oncology, The Rotterdam Eye Hospital, Schiedamse Vest 180, 3011 BH Rotterdam, The Netherlands
- Department of Pathology, Section Ophthalmic Pathology, Erasmus University Medical Center, Doctor Molewaterplein 40, 3015 GD Rotterdam, The Netherlands
- Department of Pathology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands
| |
Collapse
|
20
|
Raseley K, Jinwala Z, Zhang D, Xiao M. Single-Molecule Telomere Assay via Optical Mapping (SMTA-OM) Can Potentially Define the ALT Positivity of Cancer. Genes (Basel) 2023; 14:1278. [PMID: 37372458 DOI: 10.3390/genes14061278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Revised: 06/05/2023] [Accepted: 06/07/2023] [Indexed: 06/29/2023] Open
Abstract
Telomeres play an essential role in protecting the ends of linear chromosomes and maintaining the integrity of the human genome. One of the key hallmarks of cancers is their replicative immortality. As many as 85-90% of cancers activate the expression of telomerase (TEL+) as the telomere maintenance mechanism (TMM), and 10-15% of cancers utilize the homology-dependent repair (HDR)-based Alternative Lengthening of Telomere (ALT+) pathway. Here, we performed statistical analysis of our previously reported telomere profiling results from Single Molecule Telomere Assay via Optical Mapping (SMTA-OM), which is capable of quantifying individual telomeres from single molecules across all chromosomes. By comparing the telomeric features from SMTA-OM in TEL+ and ALT+ cancer cells, we demonstrated that ALT+ cancer cells display certain unique telomeric profiles, including increased fusions/internal telomere-like sequence (ITS+), fusions/internal telomere-like sequence loss (ITS-), telomere-free ends (TFE), super-long telomeres, and telomere length heterogeneity, compared to TEL+ cancer cells. Therefore, we propose that ALT+ cancer cells can be differentiated from TEL+ cancer cells using the SMTA-OM readouts as biomarkers. In addition, we observed variations in SMTA-OM readouts between different ALT+ cell lines that may potentially be used as biomarkers for discerning subtypes of ALT+ cancer and monitoring the response to cancer therapy.
Collapse
Affiliation(s)
- Kaitlin Raseley
- School of Biomedical Engineering, Drexel University, Philadelphia, PA 19104, USA
| | - Zeal Jinwala
- School of Biomedical Engineering, Drexel University, Philadelphia, PA 19104, USA
| | - Dong Zhang
- Department of Biomedical Sciences, College of Osteopathic Medicine, New York Institute of Technology, Old Westbury, NY 11568, USA
- Center for Cancer Research, New York Institute of Technology, Old Westbury, NY 11568, USA
| | - Ming Xiao
- School of Biomedical Engineering, Drexel University, Philadelphia, PA 19104, USA
- Center for Genomic Sciences and Center for Advanced Microbial Processing, Institute of Molecular Medicine and Infectious Disease, Drexel University College of Medicine, Philadelphia, PA 19102, USA
| |
Collapse
|
21
|
Umaru B, Sengupta S, Senthil Kumar S, Drissi R. Alternative Lengthening of Telomeres in Pediatric High-Grade Glioma and Therapeutic Implications. Cancers (Basel) 2023; 15:3070. [PMID: 37370681 DOI: 10.3390/cancers15123070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 05/31/2023] [Accepted: 06/03/2023] [Indexed: 06/29/2023] Open
Abstract
Pediatric high-grade gliomas (pHGGs), including diffuse intrinsic pontine glioma (DIPG), are highly aggressive tumors with dismal prognoses despite multimodal therapy including surgery, radiation therapy, and chemotherapy. To achieve cellular immortality cancer cells must overcome replicative senescence and apoptosis by activating telomere maintenance mechanisms (TMMs) through the reactivation of telomerase activity or using alternative lengthening of telomere (ALT) pathways. Although the ALT phenotype is more prevalent in pHGGs compared to adult HGGs, the molecular pathway and the prognostic significance of ALT activation are not well understood in pHGGs. Here, we report the heterogeneity of TMM in pHGGs and their association with genetic alterations. Additionally, we show that sensitivity to the protein kinase ataxia telangiectasia- and RAD3-related protein (ATR) inhibitor and the ATR downstream target CHK1 is not specific to pHGG ALT-positive cells. Together, these findings underscore the need for novel therapeutic strategies to target ALT in pHGG tumors.
Collapse
Affiliation(s)
- Banlanjo Umaru
- Center for Childhood Cancer Research, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Satarupa Sengupta
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, OH 45267, USA
| | - Shiva Senthil Kumar
- Center for Childhood Cancer Research, Nationwide Children's Hospital, Columbus, OH 43205, USA
| | - Rachid Drissi
- Center for Childhood Cancer Research, Nationwide Children's Hospital, Columbus, OH 43205, USA
- Department of Pediatrics, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| |
Collapse
|
22
|
Carson LM, Flynn RL. Highlighting vulnerabilities in the alternative lengthening of telomeres pathway. Curr Opin Pharmacol 2023; 70:102380. [PMID: 37149932 PMCID: PMC10247456 DOI: 10.1016/j.coph.2023.102380] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 02/03/2023] [Accepted: 03/28/2023] [Indexed: 05/09/2023]
Abstract
The alternative lengthening of telomeres (ALT) pathway is a telomere elongation mechanism found in a small but often aggressive subset of cancers. Dependent on break-induced replication, telomere extension in ALT-positive cells relies on a baseline level of DNA replication stress to initiate elongation events. This results in an elevated level of DNA damage and presents a possible vulnerability to be exploited in the development of ALT-targeted cancer therapies. Currently, there are no treatment options that target the ALT mechanism or that are specific for ALT-positive tumors. Here, we review recent developments and promising directions in the development of ALT-targeted therapeutics, many of which involve tipping the balance towards inhibition or exacerbation of ALT activity to selectively target these cells.
Collapse
Affiliation(s)
- Lisa M Carson
- Departments of Pharmacology and Experimental Therapeutics, and Medicine, Cancer Center, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Rachel L Flynn
- Departments of Pharmacology and Experimental Therapeutics, and Medicine, Cancer Center, Boston University School of Medicine, Boston, MA, 02118, USA.
| |
Collapse
|
23
|
Broderick R, Cherdyntseva V, Nieminuszczy J, Dragona E, Kyriakaki M, Evmorfopoulou T, Gagos S, Niedzwiedz W. Pathway choice in the alternative telomere lengthening in neoplasia is dictated by replication fork processing mediated by EXD2's nuclease activity. Nat Commun 2023; 14:2428. [PMID: 37105990 PMCID: PMC10140042 DOI: 10.1038/s41467-023-38029-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Accepted: 04/12/2023] [Indexed: 04/29/2023] Open
Abstract
Telomerase-independent cancer proliferation via the alternative lengthening of telomeres (ALT) relies upon two distinct, largely uncharacterized, break-induced-replication (BIR) processes. How cancer cells initiate and regulate these terminal repair mechanisms is unknown. Here, we establish that the EXD2 nuclease is recruited to ALT telomeres to direct their maintenance. We demonstrate that EXD2 loss leads to telomere shortening, elevated telomeric sister chromatid exchanges, C-circle formation as well as BIR-mediated telomeric replication. We discover that EXD2 fork-processing activity triggers a switch between RAD52-dependent and -independent ALT-associated BIR. The latter is suppressed by EXD2 but depends specifically on the fork remodeler SMARCAL1 and the MUS81 nuclease. Thus, our findings suggest that processing of stalled replication forks orchestrates elongation pathway choice at ALT telomeres. Finally, we show that co-depletion of EXD2 with BLM, DNA2 or POLD3 confers synthetic lethality in ALT cells, identifying EXD2 as a potential druggable target for ALT-reliant cancers.
Collapse
Affiliation(s)
| | - Veronica Cherdyntseva
- Laboratory of Genetics, Center of Clinical Research, Experimental Surgery and Translational Research Biomedical Research Foundation Academy of Athens (BRFAA), Athens, Greece
| | | | - Eleni Dragona
- Laboratory of Genetics, Center of Clinical Research, Experimental Surgery and Translational Research Biomedical Research Foundation Academy of Athens (BRFAA), Athens, Greece
| | - Maria Kyriakaki
- Laboratory of Genetics, Center of Clinical Research, Experimental Surgery and Translational Research Biomedical Research Foundation Academy of Athens (BRFAA), Athens, Greece
| | - Theodora Evmorfopoulou
- Laboratory of Genetics, Center of Clinical Research, Experimental Surgery and Translational Research Biomedical Research Foundation Academy of Athens (BRFAA), Athens, Greece
| | - Sarantis Gagos
- Laboratory of Genetics, Center of Clinical Research, Experimental Surgery and Translational Research Biomedical Research Foundation Academy of Athens (BRFAA), Athens, Greece.
| | | |
Collapse
|
24
|
Singh M, MacKenzie D, Desai S, Batista N, Zhang D. Diagnostic Biomarkers and Therapeutic Targets of Alternative Lengthening of Telomeres-Positive Cancers. Genet Test Mol Biomarkers 2023; 27:123-125. [PMID: 37115645 DOI: 10.1089/gtmb.2023.29069.mas] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/29/2023] Open
|
25
|
Sohn EJ, Goralsky JA, Shay JW, Min J. The Molecular Mechanisms and Therapeutic Prospects of Alternative Lengthening of Telomeres (ALT). Cancers (Basel) 2023; 15:cancers15071945. [PMID: 37046606 PMCID: PMC10093677 DOI: 10.3390/cancers15071945] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 03/14/2023] [Accepted: 03/15/2023] [Indexed: 04/14/2023] Open
Abstract
As detailed by the end replication problem, the linear ends of a cell's chromosomes, known as telomeres, shorten with each successive round of replication until a cell enters into a state of growth arrest referred to as senescence. To maintain their immortal proliferation capacity, cancer cells must employ a telomere maintenance mechanism, such as telomerase activation or the Alternative Lengthening of Telomeres pathway (ALT). With only 10-15% of cancers utilizing the ALT mechanism, progress towards understanding its molecular components and associated hallmarks has only recently been made. This review analyzes the advances towards understanding the ALT pathway by: (1) detailing the mechanisms associated with engaging the ALT pathway as well as (2) identifying potential therapeutic targets of ALT that may lead to novel cancer therapeutic treatments. Collectively, these studies indicate that the ALT molecular mechanisms involve at least two distinct pathways induced by replication stress and damage at telomeres. We suggest exploiting tumor dependency on ALT is a promising field of study because it suggests new approaches to ALT-specific therapies for cancers with poorer prognosis. While substantial progress has been made in the ALT research field, additional progress will be required to realize these advances into clinical practices to treat ALT cancers and improve patient prognoses.
Collapse
Affiliation(s)
- Eric J Sohn
- Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Julia A Goralsky
- Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Jerry W Shay
- Department of Cell Biology, University of Texas Southwestern Medical Center, Dallas, TX 75390-9039, USA
| | - Jaewon Min
- Institute for Cancer Genetics, Columbia University Irving Medical Center, New York, NY 10032, USA
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032, USA
| |
Collapse
|
26
|
Shepelev N, Dontsova O, Rubtsova M. Post-Transcriptional and Post-Translational Modifications in Telomerase Biogenesis and Recruitment to Telomeres. Int J Mol Sci 2023; 24:5027. [PMID: 36902458 PMCID: PMC10003056 DOI: 10.3390/ijms24055027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Revised: 03/02/2023] [Accepted: 03/03/2023] [Indexed: 03/08/2023] Open
Abstract
Telomere length is associated with the proliferative potential of cells. Telomerase is an enzyme that elongates telomeres throughout the entire lifespan of an organism in stem cells, germ cells, and cells of constantly renewed tissues. It is activated during cellular division, including regeneration and immune responses. The biogenesis of telomerase components and their assembly and functional localization to the telomere is a complex system regulated at multiple levels, where each step must be tuned to the cellular requirements. Any defect in the function or localization of the components of the telomerase biogenesis and functional system will affect the maintenance of telomere length, which is critical to the processes of regeneration, immune response, embryonic development, and cancer progression. An understanding of the regulatory mechanisms of telomerase biogenesis and activity is necessary for the development of approaches toward manipulating telomerase to influence these processes. The present review focuses on the molecular mechanisms involved in the major steps of telomerase regulation and the role of post-transcriptional and post-translational modifications in telomerase biogenesis and function in yeast and vertebrates.
Collapse
Affiliation(s)
- Nikita Shepelev
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Olga Dontsova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
- Skolkovo Institute of Science and Technology, Moscow 121205, Russia
| | - Maria Rubtsova
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow 117437, Russia
- Chemistry Department and Belozersky Institute of Physico-Chemical Biology, Lomonosov Moscow State University, Moscow 119234, Russia
| |
Collapse
|
27
|
Heaphy CM, Singhi AD. Reprint of: The Diagnostic and Prognostic Utility of Incorporating DAXX, ATRX, and Alternative Lengthening of Telomeres (ALT) to the Evaluation of Pancreatic Neuroendocrine Tumors (PanNETs). Hum Pathol 2023; 132:1-11. [PMID: 36702689 DOI: 10.1016/j.humpath.2023.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 01/26/2023]
Abstract
Pancreatic neuroendocrine tumors (PanNETs) are a heterogeneous group of neoplasms with increasing incidence and an ill-defined pathobiology. Although many PanNETs are indolent and remain stable for years, a subset may behave aggressively and metastasize widely. Thus, the increasing and frequent detection of PanNETs presents a treatment dilemma. Current prognostic systems are susceptible to interpretation errors, sampling issues, and do not accurately reflect the clinical behavior of these neoplasms. Hence, additional biomarkers are needed to improve the prognostic stratification of patients diagnosed with a PanNET. Recent studies have identified alterations in death domain-associated protein 6 (DAXX) and alpha-thalassemia/mental retardation X-linked (ATRX), as well as alternative lengthening of telomeres (ALT), as promising prognostic biomarkers. This review summarizes the identification, clinical utility, and specific nuances in testing for DAXX/ATRX by immunohistochemistry and ALT by telomere-specific fluorescence in situ hybridization in PanNETs. Furthermore, a discussion on diagnostic indications for DAXX, ATRX, and ALT status is provided to include the distinction between PanNETs and pancreatic neuroendocrine carcinomas (PanNECs), and determining pancreatic origin for metastatic neuroendocrine tumors in the setting of an unknown primary.
Collapse
Affiliation(s)
- Christopher M Heaphy
- Department of Medicine, Boston University, School of Medicine, Boston, MA, 02118, USA
| | - Aatur D Singhi
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA, 15213, USA.
| |
Collapse
|
28
|
Genomic Characterization of Rare Primary Cardiac Sarcoma Entities. Diagnostics (Basel) 2023; 13:diagnostics13020214. [PMID: 36673024 PMCID: PMC9858520 DOI: 10.3390/diagnostics13020214] [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: 11/12/2022] [Revised: 12/29/2022] [Accepted: 01/04/2023] [Indexed: 01/09/2023] Open
Abstract
Primary cardiac sarcomas are considered rare malignant entities associated with poor prognosis. In fact, knowledge regarding their gene signature and possible treatments is still limited. In our study, whole-transcriptome sequencing on formalin-fixed paraffin-embedded (FFPE) samples from one cardiac osteosarcoma and one cardiac leiomyosarcoma was performed, to investigate their mutational profiles and to highlight differences and/or similarities to other cardiac histotypes. Both cases have been deeply detailed from a pathological point of view. The osteosarcoma sample presented mutations involving ATRX, ERCC5, and COL1A1, while the leiomyosarcoma case showed EXT2, DNM2, and PSIP1 alterations. Altered genes, along with the most differentially expressed genes in the leiomyosarcoma or osteosarcoma sample versus the cardiac angiosarcomas and intimal sarcomas (e.g., YAF2, PAK5, and CRABP1), appeared to be associated with cell growth, proliferation, apoptosis, and the repair of DNA damage, which are key mechanisms involved in tumorigenesis. Moreover, a distinct gene expression profile was detected in the osteosarcoma sample when compared to other cardiac sarcomas. For instance, WIF1, a marker of osteoblastic differentiation, was upregulated in our bone tumor. These findings pave the way for further studies on these entities, in order to identify targeted therapies and, therefore, improve patients' prognoses.
Collapse
|
29
|
Yasir S, Thompson S, Chen ZE, Knudson R, Knutson D, Kloft-Nelson S, Graham RP, Jain D, Simon SM, Wu TT, Torbenson M. Alternative lengthening of telomeres in primary hepatic neoplasms. Hum Pathol 2023; 131:79-86. [PMID: 36370823 PMCID: PMC10756352 DOI: 10.1016/j.humpath.2022.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 10/31/2022] [Accepted: 11/04/2022] [Indexed: 11/11/2022]
Abstract
The alternative lengthening of telomeres (ALT) phenotype is characterized by ultra-bright telomeres on fluorescence in situ hybridization (FISH) and is a marker of a unique mechanism of telomere maintenance in tumors. ALT does not occur in normal tissues. ALT has been described in hepatocellular carcinoma (5-10%) and in primary hepatic angiosarcomas (75%). To study the frequency of ALT in other primary hepatic tumors, a wide range of primary hepatic neoplasms were retrieved. The tumors included the following: intrahepatic and hilar cholangiocarcinomas (N = 110), hepatic adenomas (N = 35), hepatocellular carcinomas (N = 30), fibrolamellar carcinomas (n = 11), combined cholangiocarcinoma-hepatocellular carcinomas (N = 8), carcinosarcoma (N = 10), hepatoblastomas (N = 5), hemangiomas (N = 4), angiosarcomas (N = 8), epithelioid hemangioendotheliomas (N = 10), calcified nested stromal epithelial tumor (N = 2), embryonal sarcoma (N = 2), rhabdoid tumor (N = 1), bile duct adenoma (N = 1), and angiomyolipoma (N = 1). For epithelial tumors, ALT-FISH was positive in one carcinosarcoma (10% of cases), one cholangiocarcinoma (1% of cases), and one combined hepatocellular carcinoma-cholangiocarcinoma (13% of cases). In the hepatocellular carcinoma component of both the carcinosarcoma and the combined hepatocellular carcinoma-cholangiocarcinoma, the tumor cells showed patchy marked nuclear pleomorphism akin to that described previously for chromophobe hepatocellular carcinoma, which are typically ALT FISH positive. The ALT-positive cholangiocarcinoma also showed patchy, striking nuclear pleomorphism. For soft tissue tumors, ALT was positive in two angiosarcomas (N = 2; 25% of cases). In summary, this study shows that ALT-FISH is positive in rare carcinosarcomas, cholangiocarcinomas, and combined cholangiocarcinoma-hepatocellular carcinoma. ALT is not a significant mechanism of telomere maintenance in hepatocellular adenomas or fibrolamellar carcinomas and was negative in all other tested primary hepatic neoplasms. ALT-FISH is also positive in a subset of primary hepatic angiosarcomas.
Collapse
Affiliation(s)
- Saba Yasir
- Department of Laboratory Medicine and Pathology, Mayo Clinic Rochester, MN, 55905, USA
| | - Scott Thompson
- Department of Radiology, Mayo Clinic Rochester, MN, 55905, USA
| | - Zongming Eric Chen
- Department of Laboratory Medicine and Pathology, Mayo Clinic Rochester, MN, 55905, USA
| | - Ryan Knudson
- Medical Genome Facility, Cytogenetics Core Laboratory, Mayo Clinic Rochester, MN, 55905, USA
| | - Darlene Knutson
- Medical Genome Facility, Cytogenetics Core Laboratory, Mayo Clinic Rochester, MN, 55905, USA
| | - Sara Kloft-Nelson
- Medical Genome Facility, Cytogenetics Core Laboratory, Mayo Clinic Rochester, MN, 55905, USA
| | - Rondell P Graham
- Department of Laboratory Medicine and Pathology, Mayo Clinic Rochester, MN, 55905, USA
| | | | - Sanford M Simon
- Laboratory of Cellular Biophysics, The Rockefeller University, 1230 York Avenue, NY, NY, 10065, USA
| | - Tsung-Teh Wu
- Department of Laboratory Medicine and Pathology, Mayo Clinic Rochester, MN, 55905, USA
| | - Michael Torbenson
- Department of Laboratory Medicine and Pathology, Mayo Clinic Rochester, MN, 55905, USA.
| |
Collapse
|
30
|
Viol F, Sipos B, Fahl M, Clauditz TS, Amin T, Kriegs M, Nieser M, Izbicki JR, Huber S, Lohse AW, Schrader J. Novel preclinical gastroenteropancreatic neuroendocrine neoplasia models demonstrate the feasibility of mutation-based targeted therapy. Cell Oncol (Dordr) 2022; 45:1401-1419. [PMID: 36269546 PMCID: PMC9747820 DOI: 10.1007/s13402-022-00727-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/29/2022] [Indexed: 12/15/2022] Open
Abstract
PURPOSE Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) form a rare and remarkably heterogeneous group of tumors. Therefore, establishing personalized therapies is eminently challenging. To achieve progress in preclinical drug development, there is an urgent need for relevant tumor models. METHODS We successfully established three gastroenteropancreatic neuroendocrine tumor (GEP-NET) cell lines (NT-18P, NT-18LM, NT-36) and two gastroenteropancreatic neuroendocrine carcinoma (GEP-NEC) cell lines (NT-32 and NT-38). We performed a comprehensive characterization of morphology, NET differentiation, proliferation and intracellular signaling pathways of these five cell lines and, in addition, of the NT-3 GEP-NET cell line. Additionally, we conducted panel sequencing to identify genomic alterations suitable for mutation-based targeted therapy. RESULTS We found that the GEP-NEN cell lines exhibit a stable neuroendocrine phenotype. Functional kinome profiling revealed a higher activity of serine/threonine kinases (STK) as well as protein tyrosine kinases (PTK) in the GEP-NET cell lines NT-3 and NT-18LM compared to the GEP-NEC cell lines NT-32 and NT-38. Panel sequencing revealed a mutation in Death Domain Associated Protein (DAXX), sensitizing NT-18LM to the Ataxia telangiectasia and Rad3 related (ATR) inhibitor Berzosertib, and a mutation in AT-Rich Interaction Domain 1A (ARID1A), sensitizing NT-38 to the Aurora kinase A inhibitor Alisertib. Small interfering RNA-mediated knock down of DAXX in the DAXX wild type cell line NT-3 sensitized these cells to Berzosertib. CONCLUSIONS The newly established GEP-NET and GEP-NEC cell lines represent comprehensive preclinical in vitro models suitable to decipher GEP-NEN biology and pathogenesis. Additionally, we present the first results of a GEP-NEN-specific mutation-based targeted therapy. These findings open up new potentialities for personalized therapies in GEP-NEN.
Collapse
Affiliation(s)
- Fabrice Viol
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
| | - Bence Sipos
- Internal Medicine VIII, University Hospital Tübingen, Tübingen, Germany
| | - Martina Fahl
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Till S Clauditz
- Institute of Pathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Tania Amin
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Malte Kriegs
- Laboratory of Radiobiology & Experimental Radiation Oncology, UCCH Kinomics Core Facility, Hubertus Wald Tumorzentrum, University Cancer Center Hamburg (UCCH), University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Maike Nieser
- Center for Genomics and Transcriptomics, Tübingen, Germany
| | - Jakob R Izbicki
- Department for General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Samuel Huber
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Ansgar W Lohse
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Jörg Schrader
- I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
- Department for General, Visceral and Thoracic Surgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
- Department of Medicine, Klinikum Nordfriesland, Husum, Germany.
| |
Collapse
|
31
|
Heaphy CM, Singhi AD. The diagnostic and prognostic utility of incorporating DAXX, ATRX, and alternative lengthening of telomeres to the evaluation of pancreatic neuroendocrine tumors. Hum Pathol 2022; 129:11-20. [PMID: 35872157 DOI: 10.1016/j.humpath.2022.07.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 12/14/2022]
Abstract
Pancreatic neuroendocrine tumors (PanNETs) are a heterogeneous group of neoplasms with increasing incidence and an ill-defined pathobiology. Although many PanNETs are indolent and remain stable for years, a subset may behave aggressively and metastasize widely. Thus, the increasing and frequent detection of PanNETs presents a treatment dilemma. Current prognostic systems are susceptible to interpretation errors, sampling issues, and do not accurately reflect the clinical behavior of these neoplasms. Hence, additional biomarkers are needed to improve the prognostic stratification of patients diagnosed with a PanNET. Recent studies have identified alterations in death domain-associated protein 6 (DAXX) and alpha-thalassemia/mental retardation X-linked (ATRX), as well as alternative lengthening of telomeres (ALT), as promising prognostic biomarkers. This review summarizes the identification, clinical utility, and specific nuances in testing for DAXX/ATRX by immunohistochemistry and ALT by telomere-specific fluorescence in situ hybridization in PanNETs. Furthermore, a discussion on diagnostic indications for DAXX, ATRX, and ALT status is provided to include the distinction between PanNETs and pancreatic neuroendocrine carcinomas (PanNECs), and determining pancreatic origin for metastatic neuroendocrine tumors in the setting of an unknown primary.
Collapse
Affiliation(s)
- Christopher M Heaphy
- Department of Medicine, Boston University, School of Medicine, Boston, MA, 02118, USA
| | - Aatur D Singhi
- Department of Pathology, University of Pittsburgh Medical Center, Pittsburgh, PA, 15213, USA.
| |
Collapse
|
32
|
de Lima MF, Freitas MO, Hamedani MK, Rangel-Pozzo A, Zhu XD, Mai S. Consecutive Inhibition of Telomerase and Alternative Lengthening Pathway Promotes Hodgkin's Lymphoma Cell Death. Biomedicines 2022; 10:2299. [PMID: 36140400 PMCID: PMC9496562 DOI: 10.3390/biomedicines10092299] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Revised: 08/19/2022] [Accepted: 09/12/2022] [Indexed: 11/16/2022] Open
Abstract
Telomere maintenance is key during cancer development. Malignant cells can either use telomerase or an alternative lengthening of telomere (ALT) pathway to maintain their telomere length. In Hodgkin's Lymphoma (HL), the presence of telomerase activation is established. The activation of ALT has been reported recently. Our data confirm this notion describing co-localization of the phosphorylated form of telomeric repeat-binding factor 1 (pT371-TRF1) with ALT-associated promyelocytic leukemia bodies. Surprisingly, to our knowledge, there are no published studies targeting both telomere maintenance pathways in HL. Consequently, we investigated, for the first time, the effects of both telomerase and ALT inhibition on HL cell viability: We inhibited telomerase and/or ALT, given either individually, simultaneously, or consecutively. We report that the inhibition of telomerase using BIBR1532 followed by ALT inhibition, using trabectedin, caused a decrease of greater than 90% in cell viability in three patient-derived HL cell lines. Our results suggest that HL cells are most vulnerable to the consecutive inhibition of telomerase followed by ALT inhibition.
Collapse
Affiliation(s)
- Matheus Fabiao de Lima
- Department of Physiology and Pathophysiology, CancerCare Manitoba Research Institute, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
| | - Monique Oliveira Freitas
- Genetic Service, Institute of Paediatrics and Puericulture Martagão Gesteira (IPPMG), Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro 21941-912, Brazil
| | - Mohammad K. Hamedani
- Department of Physiology and Pathophysiology, CancerCare Manitoba Research Institute, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
| | - Aline Rangel-Pozzo
- Department of Physiology and Pathophysiology, CancerCare Manitoba Research Institute, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
| | - Xu-Dong Zhu
- Department of Biology, Faculty of Science, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Sabine Mai
- Department of Physiology and Pathophysiology, CancerCare Manitoba Research Institute, University of Manitoba, Winnipeg, MB R3E 0V9, Canada
| |
Collapse
|
33
|
Gao J, Pickett HA. Targeting telomeres: advances in telomere maintenance mechanism-specific cancer therapies. Nat Rev Cancer 2022; 22:515-532. [PMID: 35790854 DOI: 10.1038/s41568-022-00490-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/25/2022] [Indexed: 12/31/2022]
Abstract
Cancer cells establish replicative immortality by activating a telomere-maintenance mechanism (TMM), be it telomerase or the alternative lengthening of telomeres (ALT) pathway. Targeting telomere maintenance represents an intriguing opportunity to treat the vast majority of all cancer types. Whilst telomerase inhibitors have historically been heralded as promising anticancer agents, the reality has been more challenging, and there are currently no therapeutic options for cancer types that use ALT despite their aggressive nature and poor prognosis. In this Review, we discuss the mechanistic differences between telomere maintenance by telomerase and ALT, the current methods used to detect each mechanism, the utility of these tests for clinical diagnosis, and recent developments in the therapeutic strategies being employed to target both telomerase and ALT. We present notable developments in repurposing established therapeutic agents and new avenues that are emerging to target cancer types according to which TMM they employ. These opportunities extend beyond inhibition of telomere maintenance, by finding and exploiting inherent weaknesses in the telomeres themselves to trigger rapid cellular effects that lead to cell death.
Collapse
Affiliation(s)
- Jixuan Gao
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW, Australia
| | - Hilda A Pickett
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW, Australia.
| |
Collapse
|
34
|
Gulve N, Su C, Deng Z, Soldan SS, Vladimirova O, Wickramasinghe J, Zheng H, Kossenkov AV, Lieberman PM. DAXX-ATRX regulation of p53 chromatin binding and DNA damage response. Nat Commun 2022; 13:5033. [PMID: 36028493 PMCID: PMC9418176 DOI: 10.1038/s41467-022-32680-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Accepted: 08/11/2022] [Indexed: 11/18/2022] Open
Abstract
DAXX and ATRX are tumor suppressor proteins that form a histone H3.3 chaperone complex and are frequently mutated in cancers with the alternative lengthening of telomeres (ALT). Here, we show that DAXX and ATRX knock-out (KO) U87-T cells that have acquired ALT-like features have defects in p53 chromatin binding and DNA damage response. RNA-seq analysis revealed that p53 pathway is among the most perturbed. ChIP-seq and ATAC-seq revealed a genome-wide reduction in p53 DNA-binding and corresponding loss of chromatin accessibility at many p53 response elements across the genome. Both DAXX and ATRX null cells showed a depletion of histone H3.3 and accumulation of γH2AX at many p53 sites, including subtelomeres. These findings indicate that loss of DAXX or ATRX can compromise p53 chromatin binding and p53 DNA damage response in ALT-like cells, providing a link between histone composition, chromatin accessibility and tumor suppressor function of p53.
Collapse
Affiliation(s)
- Nitish Gulve
- The Wistar Institute, Philadelphia, PA, 19104, USA
| | - Chenhe Su
- The Wistar Institute, Philadelphia, PA, 19104, USA
| | - Zhong Deng
- The Wistar Institute, Philadelphia, PA, 19104, USA
| | | | | | | | - Hongwu Zheng
- Weill School of Medicine, Cornell University, New York, NY, USA
| | | | | |
Collapse
|
35
|
Frank L, Rademacher A, Mücke N, Tirier SM, Koeleman E, Knotz C, Schumacher S, Stainczyk S, Westermann F, Fröhling S, Chudasama P, Rippe K. ALT-FISH quantifies alternative lengthening of telomeres activity by imaging of single-stranded repeats. Nucleic Acids Res 2022; 50:e61. [PMID: 35188570 PMCID: PMC9226501 DOI: 10.1093/nar/gkac113] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Revised: 02/01/2022] [Accepted: 02/05/2022] [Indexed: 11/14/2022] Open
Abstract
Alternative lengthening of telomeres (ALT) occurs in ∼10% of cancer entities. However, little is known about the heterogeneity of ALT activity since robust ALT detection assays with high-throughput in situ readouts are lacking. Here, we introduce ALT-FISH, a method to quantitate ALT activity in single cells from the accumulation of single-stranded telomeric DNA and RNA. It involves a one-step fluorescent in situ hybridization approach followed by fluorescence microscopy imaging. Our method reliably identified ALT in cancer cell lines from different tumor entities and was validated in three established models of ALT induction and suppression. Furthermore, we successfully applied ALT-FISH to spatially resolve ALT activity in primary tissue sections from leiomyosarcoma and neuroblastoma tumors. Thus, our assay provides insights into the heterogeneity of ALT tumors and is suited for high-throughput applications, which will facilitate screening for ALT-specific drugs.
Collapse
Affiliation(s)
- Lukas Frank
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany
| | - Anne Rademacher
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany
| | - Norbert Mücke
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany
| | - Stephan M Tirier
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany
| | - Emma Koeleman
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany
| | - Caroline Knotz
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany
| | - Sabrina Schumacher
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany
| | - Sabine A Stainczyk
- Hopp Children's Cancer Center (KiTZ), Heidelberg, Germany
- Division of Neuroblastoma Genomics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Frank Westermann
- Hopp Children's Cancer Center (KiTZ), Heidelberg, Germany
- Division of Neuroblastoma Genomics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Stefan Fröhling
- Division of Translational Medical Oncology, National Center for Tumor Diseases (NCT) Heidelberg and German Cancer Research Center (DKFZ), Heidelberg, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Priya Chudasama
- Precision Sarcoma Research Group, German Cancer Research Center (DKFZ) and National Center for Tumor Diseases (NCT), Heidelberg, Germany
| | - Karsten Rippe
- Division of Chromatin Networks, German Cancer Research Center (DKFZ) and Bioquant, Heidelberg, Germany
| |
Collapse
|
36
|
Hou K, Yu Y, Li D, Zhang Y, Zhang K, Tong J, Yang K, Jia S. Alternative Lengthening of Telomeres and Mediated Telomere Synthesis. Cancers (Basel) 2022; 14:cancers14092194. [PMID: 35565323 PMCID: PMC9105334 DOI: 10.3390/cancers14092194] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Revised: 04/24/2022] [Accepted: 04/25/2022] [Indexed: 12/01/2022] Open
Abstract
Simple Summary Alternative lengthing of telomere (ALT) is an important mechanism for maintaining telomere length and cell proliferation in telomerase-negative tumor cells. However, the molecular mechanism of ALT is still poorly understood. ALT occurs in a wide range of tumor types and usually associated with a worse clinical consequence. Here, we review the recent findings of ALT mechanisms, which promise ALT could be a valuable drug target for clinical telomerase-negative tumor treatment. Abstract Telomeres are DNA–protein complexes that protect eukaryotic chromosome ends from being erroneously repaired by the DNA damage repair system, and the length of telomeres indicates the replicative potential of the cell. Telomeres shorten during each division of the cell, resulting in telomeric damage and replicative senescence. Tumor cells tend to ensure cell proliferation potential and genomic stability by activating telomere maintenance mechanisms (TMMs) for telomere lengthening. The alternative lengthening of telomeres (ALT) pathway is the most frequently activated TMM in tumors of mesenchymal and neuroepithelial origin, and ALT also frequently occurs during experimental cellular immortalization of mesenchymal cells. ALT is a process that relies on homologous recombination (HR) to elongate telomeres. However, some processes in the ALT mechanism remain poorly understood. Here, we review the most recent understanding of ALT mechanisms and processes, which may help us to better understand how the ALT pathway is activated in cancer cells and determine the potential therapeutic targets in ALT pathway-stabilized tumors.
Collapse
Affiliation(s)
- Kailong Hou
- Faculty of Life Science and Technology, Kunming University of Science and Technology, 727 Jing Ming Nan Road, Kunming 650500, China;
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, 727 Jing Ming Nan Road, Kunming 650500, China; (Y.Y.); (D.L.); (Y.Z.); (K.Z.); (J.T.)
- First People’s Hospital of Yunnan Province, 157 Jinbi Road, Kunming 650032, China
| | - Yuyang Yu
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, 727 Jing Ming Nan Road, Kunming 650500, China; (Y.Y.); (D.L.); (Y.Z.); (K.Z.); (J.T.)
| | - Duda Li
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, 727 Jing Ming Nan Road, Kunming 650500, China; (Y.Y.); (D.L.); (Y.Z.); (K.Z.); (J.T.)
| | - Yanduo Zhang
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, 727 Jing Ming Nan Road, Kunming 650500, China; (Y.Y.); (D.L.); (Y.Z.); (K.Z.); (J.T.)
| | - Ke Zhang
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, 727 Jing Ming Nan Road, Kunming 650500, China; (Y.Y.); (D.L.); (Y.Z.); (K.Z.); (J.T.)
| | - Jinkai Tong
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, 727 Jing Ming Nan Road, Kunming 650500, China; (Y.Y.); (D.L.); (Y.Z.); (K.Z.); (J.T.)
| | - Kunxian Yang
- First People’s Hospital of Yunnan Province, 157 Jinbi Road, Kunming 650032, China
- Correspondence: (K.Y.); (S.J.)
| | - Shuting Jia
- Laboratory of Molecular Genetics of Aging and Tumor, Medical School, Kunming University of Science and Technology, 727 Jing Ming Nan Road, Kunming 650500, China; (Y.Y.); (D.L.); (Y.Z.); (K.Z.); (J.T.)
- Correspondence: (K.Y.); (S.J.)
| |
Collapse
|
37
|
Ray-Gallet D, Almouzni G. H3–H4 histone chaperones and cancer. Curr Opin Genet Dev 2022; 73:101900. [DOI: 10.1016/j.gde.2022.101900] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 01/05/2022] [Accepted: 01/07/2022] [Indexed: 12/16/2022]
|
38
|
Lu R, Pickett HA. Telomeric replication stress: the beginning and the end for alternative lengthening of telomeres cancers. Open Biol 2022; 12:220011. [PMID: 35259951 PMCID: PMC8905155 DOI: 10.1098/rsob.220011] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Telomeres are nucleoprotein structures that cap the ends of linear chromosomes. Telomeric DNA comprises terminal tracts of G-rich tandem repeats, which are inherently difficult for the replication machinery to navigate. Structural aberrations that promote activation of the alternative lengthening of telomeres (ALT) pathway of telomere maintenance exacerbate replication stress at ALT telomeres, driving fork stalling and fork collapse. This form of telomeric DNA damage perpetuates recombination-mediated repair pathways and break-induced telomere synthesis. The relationship between replication stress and DNA repair is tightly coordinated for the purpose of regulating telomere length in ALT cells, but has been shown to be experimentally manipulatable. This raises the intriguing possibility that induction of replication stress can be used as a means to cause toxic levels of DNA damage at ALT telomeres, thereby selectively disrupting the viability of ALT cancers.
Collapse
Affiliation(s)
- Robert Lu
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| | - Hilda A. Pickett
- Telomere Length Regulation Unit, Children's Medical Research Institute, Faculty of Medicine and Health, University of Sydney, Westmead, NSW 2145, Australia
| |
Collapse
|
39
|
Li D, Hou K, Zhang K, Jia S. Regulation of Replication Stress in Alternative Lengthening of Telomeres by Fanconi Anaemia Protein. Genes (Basel) 2022; 13:genes13020180. [PMID: 35205225 PMCID: PMC8872277 DOI: 10.3390/genes13020180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Revised: 01/17/2022] [Accepted: 01/19/2022] [Indexed: 02/04/2023] Open
Abstract
Fanconi anaemia (FA)-related proteins function in interstrand crosslink (ICL) repair pathways and multiple damage repair pathways. Recent studies have found that FA proteins are involved in the regulation of replication stress (RS) in alternative lengthening of telomeres (ALT). Since ALT cells often exhibit high-frequency ATRX mutations and high levels of telomeric secondary structure, high levels of DNA damage and replicative stress exist in ALT cells. Persistent replication stress is required to maintain the activity of ALT mechanistically, while excessive replication stress causes ALT cell death. FA proteins such as FANCD2 and FANCM are involved in the regulation of this balance by resolving or inhibiting the formation of telomere secondary structures to stabilize stalled replication forks and promote break-induced repair (BIR) to maintain the survival of ALT tumour cells. Therefore, we review the role of FA proteins in replication stress in ALT cells, providing a rationale and direction for the targeted treatment of ALT tumours.
Collapse
|
40
|
Cytogenomic Profile of Uterine Leiomyoma: In Vivo vs. In Vitro Comparison. Biomedicines 2021; 9:biomedicines9121777. [PMID: 34944592 PMCID: PMC8698342 DOI: 10.3390/biomedicines9121777] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 11/15/2021] [Accepted: 11/23/2021] [Indexed: 11/16/2022] Open
Abstract
We performed a comparative cytogenomic analysis of cultured and uncultured uterine leiomyoma (UL) samples. The experimental approach included karyotyping, aCGH, verification of the detected chromosomal abnormalities by metaphase and interphase FISH, MED12 mutation analysis and telomere measurement by Q-FISH. An abnormal karyotype was detected in 12 out of 32 cultured UL samples. In five karyotypically abnormal ULs, MED12 mutations were found. The chromosomal abnormalities in ULs were present mostly by complex rearrangements, including chromothripsis. In both karyotypically normal and abnormal ULs, telomeres were ~40% shorter than in the corresponding myometrium, being possibly prerequisite to chromosomal rearrangements. The uncultured samples of six karyotypically abnormal ULs were checked for the detected chromosomal abnormalities through interphase FISH with individually designed DNA probe sets. All chromosomal abnormalities detected in cultured ULs were found in corresponding uncultured samples. In all tumors, clonal spectra were present by the karyotypically abnormal cell clone/clones which coexisted with karyotypically normal ones, suggesting that chromosomal abnormalities acted as drivers, rather than triggers, of the neoplastic process. In vitro propagation did not cause any changes in the spectrum of the cell clones, but altered their ratio compared to uncultured sample. The alterations were unique for every UL. Compared to its uncultured counterpart, the frequency of chromosomally abnormal cells in the cultured sample was higher in some ULs and lower in others. To summarize, ULs are characterized by both inter- and intratumor genetic heterogeneity. Regardless of its MED12 status, a tumor may be comprised of clones with and without chromosomal abnormalities. In contrast to the clonal spectrum, which is unique and constant for each UL, the clonal frequency demonstrates up or down shifts under in vitro conditions, most probably determined by the unequal ability of cells with different genetic aberrations to exist outside the body.
Collapse
|
41
|
Payliss BJ, Patel A, Sheppard AC, Wyatt HDM. Exploring the Structures and Functions of Macromolecular SLX4-Nuclease Complexes in Genome Stability. Front Genet 2021; 12:784167. [PMID: 34804132 PMCID: PMC8599992 DOI: 10.3389/fgene.2021.784167] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Accepted: 10/21/2021] [Indexed: 12/15/2022] Open
Abstract
All organisms depend on the ability of cells to accurately duplicate and segregate DNA into progeny. However, DNA is frequently damaged by factors in the environment and from within cells. One of the most dangerous lesions is a DNA double-strand break. Unrepaired breaks are a major driving force for genome instability. Cells contain sophisticated DNA repair networks to counteract the harmful effects of genotoxic agents, thus safeguarding genome integrity. Homologous recombination is a high-fidelity, template-dependent DNA repair pathway essential for the accurate repair of DNA nicks, gaps and double-strand breaks. Accurate homologous recombination depends on the ability of cells to remove branched DNA structures that form during repair, which is achieved through the opposing actions of helicases and structure-selective endonucleases. This review focuses on a structure-selective endonuclease called SLX1-SLX4 and the macromolecular endonuclease complexes that assemble on the SLX4 scaffold. First, we discuss recent developments that illuminate the structure and biochemical properties of this somewhat atypical structure-selective endonuclease. We then summarize the multifaceted roles that are fulfilled by human SLX1-SLX4 and its associated endonucleases in homologous recombination and genome stability. Finally, we discuss recent work on SLX4-binding proteins that may represent integral components of these macromolecular nuclease complexes, emphasizing the structure and function of a protein called SLX4IP.
Collapse
Affiliation(s)
- Brandon J Payliss
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Ayushi Patel
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Anneka C Sheppard
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| | - Haley D M Wyatt
- Department of Biochemistry, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.,Canada Research Chairs Program, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada
| |
Collapse
|
42
|
Targeting of Telomeric Repeat-Containing RNA G-Quadruplexes: From Screening to Biophysical and Biological Characterization of a New Hit Compound. Int J Mol Sci 2021; 22:ijms221910315. [PMID: 34638655 PMCID: PMC8508872 DOI: 10.3390/ijms221910315] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 09/10/2021] [Accepted: 09/22/2021] [Indexed: 12/19/2022] Open
Abstract
DNA G-quadruplex (G4) structures, either within gene promoter sequences or at telomeres, have been extensively investigated as potential small-molecule therapeutic targets. However, although G4s forming at the telomeric DNA have been extensively investigated as anticancer targets, few studies focus on the telomeric repeat-containing RNA (TERRA), transcribed from telomeres, as potential pharmacological targets. Here, a virtual screening approach to identify a library of drug-like putative TERRA G4 binders, in tandem with circular dichroism melting assay to study their TERRA G4-stabilizing properties, led to the identification of a new hit compound. The affinity of this compound for TERRA RNA and some DNA G4s was analyzed through several biophysical techniques and its biological activity investigated in terms of antiproliferative effect, DNA damage response (DDR) activation, and TERRA RNA expression in high vs. low TERRA-expressing human cancer cells. The selected hit showed good affinity for TERRA G4 and no binding to double-stranded DNA. In addition, biological assays showed that this compound is endowed with a preferential cytotoxic effect on high TERRA-expressing cells, where it induces a DDR at telomeres, probably by displacing TERRA from telomeres. Our studies demonstrate that the identification of TERRA G4-targeting drugs with potential pharmacological effects is achievable, shedding light on new perspectives aimed at discovering new anticancer agents targeting these G4 structures.
Collapse
|
43
|
Akter J, Kamijo T. How Do Telomere Abnormalities Regulate the Biology of Neuroblastoma? Biomolecules 2021; 11:1112. [PMID: 34439779 PMCID: PMC8392161 DOI: 10.3390/biom11081112] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 07/20/2021] [Accepted: 07/21/2021] [Indexed: 12/25/2022] Open
Abstract
Telomere maintenance plays important roles in genome stability and cell proliferation. Tumor cells acquire replicative immortality by activating a telomere-maintenance mechanism (TMM), either telomerase, a reverse transcriptase, or the alternative lengthening of telomeres (ALT) mechanism. Recent advances in the genetic and molecular characterization of TMM revealed that telomerase activation and ALT define distinct neuroblastoma (NB) subgroups with adverse outcomes, and represent promising therapeutic targets in high-risk neuroblastoma (HRNB), an aggressive childhood solid tumor that accounts for 15% of all pediatric-cancer deaths. Patients with HRNB frequently present with widely metastatic disease, with tumors harboring recurrent genetic aberrations (MYCN amplification, TERT rearrangements, and ATRX mutations), which are mutually exclusive and capable of promoting TMM. This review provides recent insights into our understanding of TMM in NB tumors, and highlights emerging therapeutic strategies as potential treatments for telomerase- and ALT-positive tumors.
Collapse
Affiliation(s)
- Jesmin Akter
- Saitama Cancer Center, Research Institute for Clinical Oncology, Saitama 362-0806, Japan;
| | - Takehiko Kamijo
- Saitama Cancer Center, Research Institute for Clinical Oncology, Saitama 362-0806, Japan;
- Laboratory of Tumor Molecular Biology, Department of Graduate School of Science and Engineering, Saitama University, Saitama 362-0806, Japan
| |
Collapse
|