1
|
Wang H, Wang Y, Zhang D, Li P. Circulating nucleosomes as potential biomarkers for cancer diagnosis and treatment monitoring. Int J Biol Macromol 2024; 262:130005. [PMID: 38331061 DOI: 10.1016/j.ijbiomac.2024.130005] [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: 11/29/2023] [Revised: 01/03/2024] [Accepted: 02/04/2024] [Indexed: 02/10/2024]
Abstract
Nucleosomes play a crucial role in regulating gene expression through their composition and post-translational modifications. When cells die, intracellular endonucleases are activated and cleave chromatin into oligo- and mono-nucleosomes, which are then released into the body fluids. Studies have shown that the levels of nucleosomes are increased in serum and plasma in various cancer types, suggesting that analysis of circulating nucleosomes can provide an initial assessment of carcinogenesis. However, it should be noted that elevated serum nucleosome levels may not accurately diagnose certain tumor types, as increased cell death may occur in different pathological conditions. Nevertheless, detection of circulating nucleosomes and their histone modifications, along with specific tumor markers, can help diagnose certain types of cancer. Furthermore, monitoring changes in circulating nucleosome levels during chemotherapy or radiotherapy in patients with malignancies can provide valuable insights into clinical outcomes and therapeutic efficacy. The utilization of circulating nucleosomes as biomarkers is an exciting and emerging area of research, with the potential for early detection of various diseases and monitoring of treatment response. Integrating nucleosome-based biomarkers with existing ones may improve the specificity and sensitivity of current assays, offering the possibility of personalized precision medical treatment for patients.
Collapse
Affiliation(s)
- Huawei Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, 1 Ningde Road, Qingdao 266073, China.
| | - Yin Wang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, 1 Ningde Road, Qingdao 266073, China.
| | - Dejiu Zhang
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, 1 Ningde Road, Qingdao 266073, China.
| | - Peifeng Li
- Institute for Translational Medicine, The Affiliated Hospital of Qingdao University, College of Medicine, Qingdao University, 1 Ningde Road, Qingdao 266073, China.
| |
Collapse
|
2
|
Rangel-Pozzo A, Dos Santos FF, Dettori T, Giulietti M, Frau DV, Galante PAF, Vanni R, Pathak A, Fischer G, Gartner J, Caria P, Mai S. Three-dimensional nuclear architecture distinguishes thyroid cancer histotypes. Int J Cancer 2023; 153:1842-1853. [PMID: 37539710 DOI: 10.1002/ijc.34667] [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: 12/29/2022] [Revised: 06/30/2023] [Accepted: 07/04/2023] [Indexed: 08/05/2023]
Abstract
Molecular markers can serve as diagnostic tools to support pathological analysis in thyroid neoplasms. However, because the same markers can be observed in some benign thyroid lesions, additional approaches are necessary to differentiate thyroid tumor subtypes, prevent overtreatment and tailor specific clinical management. This applies particularly to the recently described variant of thyroid cancer referred to as noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). This variant has an estimated prevalence of 4.4% to 9.1% of all papillary thyroid carcinomas worldwide. We studied 60 thyroid lesions: 20 classical papillary thyroid carcinoma (CPTC), 20 follicular variant of PTC (FVPTC) and 20 NIFTP. We examined morphological and molecular features to identify parameters that can differentiate NIFTP from the other PTC subtypes. When blindly investigating the nuclear architecture of thyroid neoplasms, we observed that NIFTP has significantly longer telomeres than CPTC and FVPTC. Super-resolved 3D-structured illumination microscopy demonstrated that NIFTP is heterogeneous and that its nuclei contain more densely packed DNA and smaller interchromatin spaces than CPTC and FVPTC, a pattern that resembles normal thyroid tissue. These data are consistent with the observed indolent biological behavior and favorable prognosis associated with NIFTP, which lacks BRAFV600E mutations. Of note, next-generation thyroid oncopanel sequencing was unable to distinguish the thyroid cancer histotypes in our study cohort. In summary, our data suggest that 3D nuclear architecture can be a powerful analytical tool to diagnose and guide clinical management of NIFTP.
Collapse
Affiliation(s)
- Aline Rangel-Pozzo
- CancerCare Manitoba Research Institute, CancerCare Manitoba, University of Manitoba, Winnipeg, Canada
| | - Filipe F Dos Santos
- Centro de Oncologia Molecular, Hospital Sirio-Libanes, Sao Paulo, Brazil
- Department of Biochemistry, Chemistry Institute, Universidade de Sao Paulo, Sao Paulo, Brazil
| | - Tinuccia Dettori
- Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Matteo Giulietti
- Department of Specialistic Clinical and Odontostomatological Sciences, Polytechnic University of Marche, Ancona, Italy
| | | | - Pedro A F Galante
- Centro de Oncologia Molecular, Hospital Sirio-Libanes, Sao Paulo, Brazil
| | - Roberta Vanni
- University of Cagliari, Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Alok Pathak
- Department of Surgery, University of Manitoba, Winnipeg, Canada
| | - Gabor Fischer
- Department of Pathology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
| | - John Gartner
- Department of Pathology, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, Canada
| | - Paola Caria
- Department of Biomedical Sciences, University of Cagliari, Monserrato, Italy
| | - Sabine Mai
- CancerCare Manitoba Research Institute, CancerCare Manitoba, University of Manitoba, Winnipeg, Canada
| |
Collapse
|
3
|
Hill SL, Rogan PK, Wang YX, Knoll JHM. Differentially accessible, single copy sequences form contiguous domains along metaphase chromosomes that are conserved among multiple tissues. Mol Cytogenet 2021; 14:49. [PMID: 34670606 PMCID: PMC8527651 DOI: 10.1186/s13039-021-00567-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 09/08/2021] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND During mitosis, chromatin engages in a dynamic cycle of condensation and decondensation. Condensation into distinct units to ensure high fidelity segregation is followed by rapid and reproducible decondensation to produce functional daughter cells. Factors contributing to the reproducibility of chromatin structure between cell generations are not well understood. We investigated local metaphase chromosome condensation along mitotic chromosomes within genomic intervals showing differential accessibility (DA) between homologs. DA was originally identified using short sequence-defined single copy (sc) DNA probes of < 5 kb in length by fluorescence in situ hybridization (scFISH) in peripheral lymphocytes. These structural differences between metaphase homologs are non-random, stable, and heritable epigenetic marks which have led to the proposed function of DA as a marker of chromatin memory. Here, we characterize the organization of DA intervals into chromosomal domains by identifying multiple DA loci in close proximity to each other and examine the conservation of DA between tissues. RESULTS We evaluated multiple adjacent scFISH probes at 6 different DA loci from chromosomal regions 2p23, 3p24, 12p12, 15q22, 15q24 and 20q13 within peripheral blood T-lymphocytes. DA was organized within domains that extend beyond the defined boundaries of individual scFISH probes. Based on hybridizations of 2 to 4 scFISH probes per domain, domains ranged in length from 16.0 kb to 129.6 kb. Transcriptionally inert chromosomal DA regions in T-lymphocytes also demonstrated conservation of DA in bone marrow and fibroblast cells. CONCLUSIONS We identified novel chromosomal regions with allelic differences in metaphase chromosome accessibility and demonstrated that these accessibility differences appear to be aggregated into contiguous domains extending beyond individual scFISH probes. These domains are encompassed by previously established topologically associated domain (TAD) boundaries. DA appears to be a conserved feature of human metaphase chromosomes across different stages of lymphocyte differentiation and germ cell origin, consistent with its proposed role in maintenance of intergenerational cellular chromosome memory.
Collapse
Affiliation(s)
- Seana L Hill
- Department of Pathology & Laboratory Medicine, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Canada
| | - Peter K Rogan
- Departments of Biochemistry and Oncology, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Canada
- Cytognomix Inc., London, ON, Canada
| | - Yi Xuan Wang
- Department of Pathology & Laboratory Medicine, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Canada
| | - Joan H M Knoll
- Department of Pathology & Laboratory Medicine, Schulich School of Medicine & Dentistry, University of Western Ontario, London, Canada.
- Cytognomix Inc., London, ON, Canada.
| |
Collapse
|
4
|
Falk M, Hausmann M. A Paradigm Revolution or Just Better Resolution-Will Newly Emerging Superresolution Techniques Identify Chromatin Architecture as a Key Factor in Radiation-Induced DNA Damage and Repair Regulation? Cancers (Basel) 2020; 13:E18. [PMID: 33374540 PMCID: PMC7793109 DOI: 10.3390/cancers13010018] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Accepted: 12/18/2020] [Indexed: 02/07/2023] Open
Abstract
DNA double-strand breaks (DSBs) have been recognized as the most serious lesions in irradiated cells. While several biochemical pathways capable of repairing these lesions have been identified, the mechanisms by which cells select a specific pathway for activation at a given DSB site remain poorly understood. Our knowledge of DSB induction and repair has increased dramatically since the discovery of ionizing radiation-induced foci (IRIFs), initiating the possibility of spatiotemporally monitoring the assembly and disassembly of repair complexes in single cells. IRIF exploration revealed that all post-irradiation processes-DSB formation, repair and misrepair-are strongly dependent on the characteristics of DSB damage and the microarchitecture of the whole affected chromatin domain in addition to the cell status. The microscale features of IRIFs, such as their morphology, mobility, spatiotemporal distribution, and persistence kinetics, have been linked to repair mechanisms. However, the influence of various biochemical and structural factors and their specific combinations on IRIF architecture remains unknown, as does the hierarchy of these factors in the decision-making process for a particular repair mechanism at each individual DSB site. New insights into the relationship between the physical properties of the incident radiation, chromatin architecture, IRIF architecture, and DSB repair mechanisms and repair efficiency are expected from recent developments in optical superresolution microscopy (nanoscopy) techniques that have shifted our ability to analyze chromatin and IRIF architectures towards the nanoscale. In the present review, we discuss this relationship, attempt to correlate still rather isolated nanoscale studies with already better-understood aspects of DSB repair at the microscale, and consider whether newly emerging "correlated multiscale structuromics" can revolutionarily enhance our knowledge in this field.
Collapse
Affiliation(s)
- Martin Falk
- Institute of Biophysics, The Czech Academy of Sciences, 612 65 Brno, Czech Republic
| | - Michael Hausmann
- Kirchhoff Institute for Physics, Heidelberg University, 69120 Heidelberg, Germany;
| |
Collapse
|
5
|
Thiecke MJ, Wutz G, Muhar M, Tang W, Bevan S, Malysheva V, Stocsits R, Neumann T, Zuber J, Fraser P, Schoenfelder S, Peters JM, Spivakov M. Cohesin-Dependent and -Independent Mechanisms Mediate Chromosomal Contacts between Promoters and Enhancers. Cell Rep 2020; 32:107929. [PMID: 32698000 PMCID: PMC7383238 DOI: 10.1016/j.celrep.2020.107929] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 06/01/2020] [Accepted: 06/29/2020] [Indexed: 12/20/2022] Open
Abstract
It is currently assumed that 3D chromosomal organization plays a central role in transcriptional control. However, depletion of cohesin and CTCF affects the steady-state levels of only a minority of transcripts. Here, we use high-resolution Capture Hi-C to interrogate the dynamics of chromosomal contacts of all annotated human gene promoters upon degradation of cohesin and CTCF. We show that a majority of promoter-anchored contacts are lost in these conditions, but many contacts with distinct properties are maintained, and some new ones are gained. The rewiring of contacts between promoters and active enhancers upon cohesin degradation associates with rapid changes in target gene transcription as detected by SLAM sequencing (SLAM-seq). These results provide a mechanistic explanation for the limited, but consistent, effects of cohesin and CTCF depletion on steady-state transcription and suggest the existence of both cohesin-dependent and -independent mechanisms of enhancer-promoter pairing.
Collapse
Affiliation(s)
- Michiel J Thiecke
- Nuclear Dynamics Programme, Babraham Institute, Cambridge CB22 3AT, UK
| | - Gordana Wutz
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna 1030, Austria
| | - Matthias Muhar
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna 1030, Austria
| | - Wen Tang
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna 1030, Austria
| | - Stephen Bevan
- Nuclear Dynamics Programme, Babraham Institute, Cambridge CB22 3AT, UK; Epigenetics Programme, Babraham Institute, Cambridge CB22 3AT, UK
| | - Valeriya Malysheva
- Nuclear Dynamics Programme, Babraham Institute, Cambridge CB22 3AT, UK; MRC London Institute of Medical Sciences, London W12 0NN, UK; Institute of Clinical Sciences, Faculty of Medicine, Imperial College, London W12 0NN, UK
| | - Roman Stocsits
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna 1030, Austria
| | - Tobias Neumann
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna 1030, Austria
| | - Johannes Zuber
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna 1030, Austria
| | - Peter Fraser
- Nuclear Dynamics Programme, Babraham Institute, Cambridge CB22 3AT, UK; Department of Biological Science, Florida State University, Tallahassee, FL 32301, USA
| | - Stefan Schoenfelder
- Nuclear Dynamics Programme, Babraham Institute, Cambridge CB22 3AT, UK; Epigenetics Programme, Babraham Institute, Cambridge CB22 3AT, UK
| | - Jan-Michael Peters
- Research Institute of Molecular Pathology, Vienna Biocenter, Vienna 1030, Austria
| | - Mikhail Spivakov
- Nuclear Dynamics Programme, Babraham Institute, Cambridge CB22 3AT, UK; MRC London Institute of Medical Sciences, London W12 0NN, UK; Institute of Clinical Sciences, Faculty of Medicine, Imperial College, London W12 0NN, UK.
| |
Collapse
|
6
|
Cycles of protein condensation and discharge in nuclear organelles studied by fluorescence lifetime imaging. Nat Commun 2019; 10:455. [PMID: 30692529 PMCID: PMC6349932 DOI: 10.1038/s41467-019-08354-3] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2018] [Accepted: 01/03/2019] [Indexed: 02/07/2023] Open
Abstract
Nuclear organelles are viscous droplets, created by concentration-dependent condensation and liquid–liquid phase separation of soluble proteins. Nuclear organelles have been actively investigated for their role in cellular regulation and disease. However, these studies are highly challenging to perform in live cells, and therefore, their physico-chemical properties are still poorly understood. In this study, we describe a fluorescence lifetime imaging approach for real-time monitoring of protein condensation in nuclear organelles of live cultured cells. This approach unravels surprisingly large cyclic changes in concentration of proteins in major nuclear organelles including nucleoli, nuclear speckles, Cajal bodies, as well as in the clusters of heterochromatin. Remarkably, protein concentration changes are synchronous for different organelles of the same cells. We propose a molecular mechanism responsible for synchronous accumulations of proteins in the nuclear organelles. This mechanism can serve for general regulation of cellular metabolism and contribute to coordination of gene expression. Studying the condensation of proteins into membraneless organelles in live cells is highly challenging. Here the authors develop a fluorescence lifetime imaging approach to monitor the condensation of proteins in nuclear organelles and report coordinated and cyclic changes in several nuclear organelles.
Collapse
|
7
|
Hensel KO, Cantner F, Bangert F, Wirth S, Postberg J. Episomal HBV persistence within transcribed host nuclear chromatin compartments involves HBx. Epigenetics Chromatin 2018; 11:34. [PMID: 29933745 PMCID: PMC6015472 DOI: 10.1186/s13072-018-0204-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 06/19/2018] [Indexed: 02/06/2023] Open
Abstract
Background In hepatocyte nuclei, hepatitis B virus (HBV) genomes occur episomally as covalently closed circular DNA (cccDNA). The HBV X protein (HBx) is required to initiate and maintain HBV replication. The functional nuclear localization of cccDNA and HBx remains unexplored. Results To identify virus–host genome interactions and the underlying nuclear landscape for the first time, we combined circular chromosome conformation capture (4C) with RNA-seq and ChIP-seq. Moreover, we studied HBx-binding to HBV episomes. In HBV-positive HepaRG hepatocytes, we observed preferential association of HBV episomes and HBx with actively transcribed nuclear domains on the host genome correlating in size with constrained topological units of chromatin. Interestingly, HBx alone occupied transcribed chromatin domains. Silencing of native HBx caused reduced episomal HBV stability. Conclusions As part of the HBV episome, HBx might stabilize HBV episomal nuclear localization. Our observations may contribute to the understanding of long-term episomal stability and the facilitation of viral persistence. The exact mechanism by which HBx contributes to HBV nuclear persistence warrants further investigations. Electronic supplementary material The online version of this article (10.1186/s13072-018-0204-2) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Kai O Hensel
- Department of Pediatrics, HELIOS University Hospital Wuppertal, Centre for Clinical and Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Heusnerstr. 40, 42283, Wuppertal, Germany.,Department of Paediatric Gastroenterology, Hepatology and Nutrition, University of Cambridge, Addenbrooke's Hospital, Hills Road, Cambridge,, CB2 0QQ, UK
| | - Franziska Cantner
- Department of Pediatrics, HELIOS University Hospital Wuppertal, Centre for Clinical and Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Heusnerstr. 40, 42283, Wuppertal, Germany
| | - Felix Bangert
- Department of Pediatrics, HELIOS University Hospital Wuppertal, Centre for Clinical and Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Heusnerstr. 40, 42283, Wuppertal, Germany
| | - Stefan Wirth
- Department of Pediatrics, HELIOS University Hospital Wuppertal, Centre for Clinical and Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Heusnerstr. 40, 42283, Wuppertal, Germany
| | - Jan Postberg
- Department of Pediatrics, HELIOS University Hospital Wuppertal, Centre for Clinical and Translational Research (CCTR), Faculty of Health, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Heusnerstr. 40, 42283, Wuppertal, Germany. .,Clinical Molecular Genetics and Epigenetics, Faculty of Health, School of Medicine, Centre for Biomedical Education and Research (ZBAF), Witten/Herdecke University, Alfred-Herrhausen-Str. 50, 58448, Witten, Germany.
| |
Collapse
|
8
|
Mukherjee A, Patterson AL, George JW, Carpenter TJ, Madaj ZB, Hostetter G, Risinger JI, Teixeira JM. Nuclear PTEN Localization Contributes to DNA Damage Response in Endometrial Adenocarcinoma and Could Have a Diagnostic Benefit for Therapeutic Management of the Disease. Mol Cancer Ther 2018; 17:1995-2003. [DOI: 10.1158/1535-7163.mct-17-1255] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 04/30/2018] [Accepted: 06/07/2018] [Indexed: 11/16/2022]
|
9
|
Circulating Nucleosomes and Nucleosome Modifications as Biomarkers in Cancer. Cancers (Basel) 2017; 9:cancers9010005. [PMID: 28075351 PMCID: PMC5295776 DOI: 10.3390/cancers9010005] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2016] [Revised: 12/31/2016] [Accepted: 01/01/2017] [Indexed: 12/17/2022] Open
Abstract
Traditionally the stratification of many cancers involves combining tumour and clinicopathological features (e.g., patient age; tumour size, grade, receptor status and location) to inform treatment options and predict recurrence risk and survival. However, current biomarkers often require invasive excision of the tumour for profiling, do not allow monitoring of the response to treatment and stratify patients into broad heterogeneous groups leading to inconsistent treatment responses. Here we explore and describe the benefits of using circulating biomarkers (nucleosomes and/or modifications to nucleosomes) as a non-invasive method for detecting cancer and monitoring response to treatment. Nucleosomes (DNA wound around eight core histone proteins) are responsible for compacting our genome and their composition and post-translational modifications are responsible for regulating gene expression. Here, we focus on breast and colorectal cancer as examples where utilizing circulating nucleosomes as biomarkers hold real potential as liquid biopsies. Utilizing circulating nucleosomes as biomarkers is an exciting new area of research that promises to allow both the early detection of cancer and monitoring of treatment response. Nucleosome-based biomarkers combine with current biomarkers, increasing both specificity and sensitivity of current tests and have the potential to provide individualised precision-medicine based treatments for patients.
Collapse
|
10
|
Zhang Z, Hou SQ, He J, Gu T, Yin Y, Shen WH. PTEN regulates PLK1 and controls chromosomal stability during cell division. Cell Cycle 2016; 15:2476-85. [PMID: 27398835 PMCID: PMC5026806 DOI: 10.1080/15384101.2016.1203493] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2016] [Revised: 06/12/2016] [Accepted: 06/13/2016] [Indexed: 12/28/2022] Open
Abstract
PTEN functions as a guardian of the genome through multiple mechanisms. We have previously established that PTEN maintains the structural integrity of chromosomes. In this report, we demonstrate a fundamental role of PTEN in controlling chromosome inheritance to prevent gross genomic alterations. Disruption of PTEN or depletion of PTEN protein phosphatase activity causes abnormal chromosome content, manifested by enlarged or polyploid nuclei. We further identify polo-like kinase 1 (PLK1) as a substrate of PTEN phosphatase. PTEN can physically associate with PLK1 and reduce PLK1 phosphorylation in a phosphatase-dependent manner. We show that PTEN deficiency leads to PLK1 phosphorylation and that a phospho-mimicking PLK1 mutant causes polyploidy, imitating functional deficiency of PTEN phosphatase. Inhibition of PLK1 activity or overexpression of a non-phosphorylatable PLK1 mutant reduces the polyploid cell population. These data reveal a new mechanism by which PTEN controls genomic stability during cell division.
Collapse
Affiliation(s)
- Zhong Zhang
- Department of Radiation Oncology, Weill Medical Medicine, Cornell University, New York, NY, USA
| | - Sheng-Qi Hou
- Department of Radiation Oncology, Weill Medical Medicine, Cornell University, New York, NY, USA
| | - Jinxue He
- Department of Radiation Oncology, Weill Medical Medicine, Cornell University, New York, NY, USA
| | - Tingting Gu
- Department of Radiation Oncology, Weill Medical Medicine, Cornell University, New York, NY, USA
| | - Yuxin Yin
- Department of Radiation Oncology, Weill Medical Medicine, Cornell University, New York, NY, USA
- Present address: Institute of Systems Biomedicine, Department of Pathology, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, China
| | - Wen H. Shen
- Department of Radiation Oncology, Weill Medical Medicine, Cornell University, New York, NY, USA
| |
Collapse
|
11
|
PTEN regulates EG5 to control spindle architecture and chromosome congression during mitosis. Nat Commun 2016; 7:12355. [PMID: 27492783 PMCID: PMC4980451 DOI: 10.1038/ncomms12355] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2015] [Accepted: 06/24/2016] [Indexed: 02/07/2023] Open
Abstract
Architectural integrity of the mitotic spindle is required for efficient chromosome congression and accurate chromosome segregation to ensure mitotic fidelity. Tumour suppressor PTEN has multiple functions in maintaining genome stability. Here we report an essential role of PTEN in mitosis through regulation of the mitotic kinesin motor EG5 for proper spindle architecture and chromosome congression. PTEN depletion results in chromosome misalignment in metaphase, often leading to catastrophic mitotic failure. In addition, metaphase cells lacking PTEN exhibit defects of spindle geometry, manifested prominently by shorter spindles. PTEN is associated and co-localized with EG5 during mitosis. PTEN deficiency induces aberrant EG5 phosphorylation and abrogates EG5 recruitment to the mitotic spindle apparatus, leading to spindle disorganization. These data demonstrate the functional interplay between PTEN and EG5 in controlling mitotic spindle structure and chromosome behaviour during mitosis. We propose that PTEN functions to equilibrate mitotic phosphorylation for proper spindle formation and faithful genomic transmission. One of the cellular functions of the tumour suppressor PTEN is to maintain genome stability. Here, the authors show that PTEN depletion leads to mitotic spindle shortening and chromosome misalignment due to aberrant EG5 activation.
Collapse
|