1
|
Zhao D, Zhang M, Huang S, Liu Q, Zhu S, Li Y, Jiang W, Kiss DL, Cao Q, Zhang L, Chen K. CHD6 promotes broad nucleosome eviction for transcriptional activation in prostate cancer cells. Nucleic Acids Res 2022; 50:12186-12201. [PMID: 36408932 PMCID: PMC9757051 DOI: 10.1093/nar/gkac1090] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2022] [Accepted: 11/19/2022] [Indexed: 11/22/2022] Open
Abstract
Despite being a member of the chromodomain helicase DNA-binding protein family, little is known about the exact role of CHD6 in chromatin remodeling or cancer disease. Here we show that CHD6 binds to chromatin to promote broad nucleosome eviction for transcriptional activation of many cancer pathways. By integrating multiple patient cohorts for bioinformatics analysis of over a thousand prostate cancer datasets, we found CHD6 expression elevated in prostate cancer and associated with poor prognosis. Further comprehensive experiments demonstrated that CHD6 regulates oncogenicity of prostate cancer cells and tumor development in a murine xenograft model. ChIP-Seq for CHD6, along with MNase-Seq and RNA-Seq, revealed that CHD6 binds on chromatin to evict nucleosomes from promoters and gene bodies for transcriptional activation of oncogenic pathways. These results demonstrated a key function of CHD6 in evicting nucleosomes from chromatin for transcriptional activation of prostate cancer pathways.
Collapse
Affiliation(s)
- Dongyu Zhao
- Department of Biomedical Informatics, MOE Key Lab of Cardiovascular Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
- Prostate Cancer Program, Dana-Farber and Harvard Cancer Center, Harvard University, Boston, MA 02115, USA
- Basic and Translational Research Division, Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX 77030, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Min Zhang
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Shaodong Huang
- Department of Biomedical Informatics, MOE Key Lab of Cardiovascular Sciences, School of Basic Medical Sciences, Peking University Health Science Center, Beijing, 100191, China
| | - Qi Liu
- Department of Urology, and Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Sen Zhu
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Yanqiang Li
- Prostate Cancer Program, Dana-Farber and Harvard Cancer Center, Harvard University, Boston, MA 02115, USA
- Basic and Translational Research Division, Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX 77030, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Weihua Jiang
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Daniel L Kiss
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX 77030, USA
| | - Qi Cao
- Center for Inflammation and Epigenetics, Houston Methodist Research Institute, Houston, TX 77030, USA
- Department of Urology, and Robert H. Lurie Comprehensive Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Lili Zhang
- Basic and Translational Research Division, Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX 77030, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| | - Kaifu Chen
- Prostate Cancer Program, Dana-Farber and Harvard Cancer Center, Harvard University, Boston, MA 02115, USA
- Basic and Translational Research Division, Department of Cardiology, Boston Children's Hospital, Boston, MA 02115, USA
- Department of Cardiovascular Sciences, Houston Methodist Research Institute, Houston, TX 77030, USA
- Department of Pediatrics, Harvard Medical School, Boston, MA 02115, USA
| |
Collapse
|
2
|
Ding L, Zhao X, Xiong Q, Jiang X, Liu X, Ding K, Zhou P. Cdc25B is transcriptionally inhibited by IER5 through the NF-YB transcription factor in irradiation-treated HeLa cells. Toxicol Res (Camb) 2021; 10:875-884. [PMID: 34484679 DOI: 10.1093/toxres/tfab069] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 05/28/2021] [Accepted: 07/05/2021] [Indexed: 12/09/2022] Open
Abstract
Cervical cancer (CC) is a type of pelvic malignant tumor that severely threatens women's health. Current evidence suggests that IER5, as a potential radiosensitizer, promotes irradiation-induced apoptosis in CC tissues in patients undergoing chemoradiotherapy. IER5 has been shown to be involved in the G2/M-phase transition. In the present study, we used Cdc25B as the breakthrough point to explore the underlying mechanism of IER5 in the cell cycle regulation of radiation-damaged HeLa cells. IER5 was evidently upregulated after irradiation, but Cdc25B was significantly downregulated. In monoclonal IER5-silenced HeLa cells, irradiation-induced downregulation of Cdc25B was attenuated. The effect of irradiation on Cdc25B promoter activity was determined by dual-luciferase reporter assays. The response elements on the Cdc25B promoter related to irradiation were predicted by JASPAR. These conserved sequences were mutated individually or in combination by splicing-by-overlap extension PCR, and their function was confirmed by dual-luciferase reporter assays. The enrichment efficiency of transcription factors after irradiation was determined by chromatin immunoprecipitation (ChIP) assay. Both Sp1/Sp3 and NF-YB binding sites were involved in irradiation-mediated regulation of Cdc25B. IER5 was involved in irradiation-mediated regulation of Cdc25B through the NF-YB binding site. Furthermore, ChIP assays showed that IER5 bound to the Cdc25B promoter, and the binding of IER5 to the Cdc25B promoter region in irradiation-induced HeLa cells induced the release of the coactivator p300 through interaction with NF-YB. Taken together, these findings indicate that IER5 is the transcriptional repressor that accelerates the downregulation of Cdc25B expression after irradiation.
Collapse
Affiliation(s)
- Lixin Ding
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Xianzhe Zhao
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Qiang Xiong
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Xiaoyan Jiang
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Xiaodan Liu
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Haidian District, Beijing 100850, P. R. China
| | - Kuke Ding
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Xicheng District, Beijing 100088, P. R. China
| | - Pingkun Zhou
- Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Haidian District, Beijing 100850, P. R. China
| |
Collapse
|
3
|
Ganesh RA, Venkataraman K, Sirdeshmukh R. GPR56: An adhesion GPCR involved in brain development, neurological disorders and cancer. Brain Res 2020; 1747:147055. [PMID: 32798453 DOI: 10.1016/j.brainres.2020.147055] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 07/04/2020] [Accepted: 08/11/2020] [Indexed: 12/15/2022]
Abstract
GPR56/ADGRG1 is a member of the adhesion G-protein coupled receptor (aGPCR) family and one of the important players in the normal development of the brain. It plays a pivotal role in the diverse neurobiological processes, including cortical formation, oligodendrocyte development, and myelination. Mutations in GPR56 are known to cause brain malformation, myelination defects and are also implied in many cancers, including brain tumors. Since its identification almost two decades ago, GPR56 has emerged from an orphaned and uncharacterized GPCR to an increasingly well studied receptor. Yet, much needs to be understood about GPR56, both in terms of its molecular interactions and biological functions that may be relevant in normal health and disease. The review is focussed on the recent available knowledge of GPR56, which would give useful insights into its known and potential roles in the human brain, neurological disorders, and brain tumors like glioblastoma.
Collapse
Affiliation(s)
- Raksha A Ganesh
- Mazumdar Shaw Center for Translational Research, Narayana Health, Bangalore 560099, India; Center for Bio-Separation Technology, Vellore Institute of Technology, Vellore 632104, India
| | - Krishnan Venkataraman
- Center for Bio-Separation Technology, Vellore Institute of Technology, Vellore 632104, India
| | - Ravi Sirdeshmukh
- Mazumdar Shaw Center for Translational Research, Narayana Health, Bangalore 560099, India; Institute of Bioinformatics, International Tech Park, Bangalore 560066, India; Manipal Academy of Higher Education, Manipal 576104, India.
| |
Collapse
|
4
|
Schaffner-Reckinger E, Machado RAC. The actin-bundling protein L-plastin-A double-edged sword: Beneficial for the immune response, maleficent in cancer. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2020; 355:109-154. [PMID: 32859369 DOI: 10.1016/bs.ircmb.2020.05.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The dynamic organization of the actin cytoskeleton into bundles and networks is orchestrated by a large variety of actin-binding proteins. Among them, the actin-bundling protein L-plastin is normally expressed in hematopoietic cells, where it is involved in the immune response. However, L-plastin is also often ectopically expressed in malignant cancer cells of non-hematopoietic origin and is even considered as a marker for cancer progression. Post-translational modification modulates L-plastin activity. In particular, L-plastin Ser5 phosphorylation has been shown to be important for the immune response in leukocytes as well as for invasion and metastasis formation of carcinoma cells. This chapter discusses the physiological and pathological role of L-plastin with a special focus on the importance of L-plastin Ser5 phosphorylation for the protein functions. The potential use of Ser5 phosphorylated L-plastin as a biomarker and/or therapeutic target will be evoked.
Collapse
Affiliation(s)
- Elisabeth Schaffner-Reckinger
- Cancer Cell Biology and Drug Discovery Group, Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg.
| | - Raquel A C Machado
- Cancer Cell Biology and Drug Discovery Group, Faculty of Science, Technology and Medicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| |
Collapse
|
5
|
Freudenmann LK, Mayer C, Rodemann HP, Dittmann K. Reduced exosomal L-Plastin is responsible for radiation-induced bystander effect. Exp Cell Res 2019; 383:111498. [PMID: 31302031 DOI: 10.1016/j.yexcr.2019.111498] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 07/08/2019] [Accepted: 07/10/2019] [Indexed: 01/21/2023]
Abstract
Radiation-induced bystander effects (RIBE) are discussed as relevant processes during radiotherapy. Irradiated cells are suggested to release growth-inhibitory/DNA-damaging factors transported to non-irradiated cells. However, the molecular nature of this phenomenon has not yet been resolved. We aimed at identifying the growth-inhibitory factor(s) transmitted to non-irradiated cells. RIBE-competent PC3 cells were used to produce conditioned medium (CM) after exposure to ionizing radiation. Indicator cells were incubated with CM and clonogenic survival as well as cell proliferation were determined as endpoints. A549 indicator cells exhibited a bystander effect upon incubation with CM from irradiated PC3 cells. This bystander effect was not due to DNA-damaging factors, but a radiation-triggered reduction of mitogenic/clonogenic activity present in CM. Several tumor cells, but not normal fibroblasts secrete this factor, whose release is reduced by irradiation. We identified L-Plastin to be responsible for the mitogenic/clonogenic activity. Removal of L-Plastin from CM by immunoprecipitation or siRNA-mediated knockdown of L-Plastin expression resulted in loss or reduction of mitogenic/clonogenic activity transmitted via CM, respectively. Exosome-transported L-Plastin was constitutively Ser5-phosphorylated, indicative of its bioactive conformation. In summary, we observed production and exosomal secretion of L-Plastin by cancer cells. Via exosome-transmitted L-Plastin, tumors induce clonogenic and mitogenic activity in cancer and normal cells of the tumor microenvironment. Irradiation inhibits L-Plastin production targeting both cancer cells and the tumor niche and may explain the high impact of radiotherapy in tumor control.
Collapse
Affiliation(s)
- Lena Katharina Freudenmann
- Division of Radiobiology and Molecular Environmental Research, Department of Radiation Oncology, University of Tübingen, Germany; DKFZ Partner Site Tübingen, German Cancer Consortium (DKTK), Germany
| | - Claus Mayer
- Division of Radiobiology and Molecular Environmental Research, Department of Radiation Oncology, University of Tübingen, Germany; DKFZ Partner Site Tübingen, German Cancer Consortium (DKTK), Germany
| | - H Peter Rodemann
- Division of Radiobiology and Molecular Environmental Research, Department of Radiation Oncology, University of Tübingen, Germany; DKFZ Partner Site Tübingen, German Cancer Consortium (DKTK), Germany
| | - Klaus Dittmann
- Division of Radiobiology and Molecular Environmental Research, Department of Radiation Oncology, University of Tübingen, Germany; DKFZ Partner Site Tübingen, German Cancer Consortium (DKTK), Germany.
| |
Collapse
|
6
|
Moore S, Berger ND, Luijsterburg MS, Piett CG, Stanley FKT, Schräder CU, Fang S, Chan JA, Schriemer DC, Nagel ZD, van Attikum H, Goodarzi AA. The CHD6 chromatin remodeler is an oxidative DNA damage response factor. Nat Commun 2019; 10:241. [PMID: 30651562 PMCID: PMC6335469 DOI: 10.1038/s41467-018-08111-y] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Accepted: 12/14/2018] [Indexed: 02/07/2023] Open
Abstract
Cell survival after oxidative DNA damage requires signaling, repair and transcriptional events often enabled by nucleosome displacement, exchange or removal by chromatin remodeling enzymes. Here, we show that Chromodomain Helicase DNA-binding protein 6 (CHD6), distinct to other CHD enzymes, is stabilized during oxidative stress via reduced degradation. CHD6 relocates rapidly to DNA damage in a manner dependent upon oxidative lesions and a conserved N-terminal poly(ADP-ribose)-dependent recruitment motif, with later retention requiring the double chromodomain and central core. CHD6 ablation increases reactive oxygen species persistence and impairs anti-oxidant transcriptional responses, leading to elevated DNA breakage and poly(ADP-ribose) induction that cannot be rescued by catalytic or double chromodomain mutants. Despite no overt epigenetic or DNA repair abnormalities, CHD6 loss leads to impaired cell survival after chronic oxidative stress, abnormal chromatin relaxation, amplified DNA damage signaling and checkpoint hypersensitivity. We suggest that CHD6 is a key regulator of the oxidative DNA damage response. Oxidative DNA damage is associated with nucleosome respacing and transcriptional changes requiring chromatin remodeling enzymes. Here, the authors reveal that the CHD6 remodeler is a DNA damage response factor that relocates to damaged sites and promotes cell survival following oxidative damage.
Collapse
Affiliation(s)
- Shaun Moore
- Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Departments of Biochemistry & Molecular Biology and/or Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - N Daniel Berger
- Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Departments of Biochemistry & Molecular Biology and/or Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Martijn S Luijsterburg
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, The Netherlands
| | - Cortt G Piett
- Harvard University, School of Public Health, Boston, MA, 02115, USA
| | - Fintan K T Stanley
- Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Departments of Biochemistry & Molecular Biology and/or Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Christoph U Schräder
- Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Departments of Biochemistry & Molecular Biology and/or Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Shujuan Fang
- Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Departments of Biochemistry & Molecular Biology and/or Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Jennifer A Chan
- Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Departments of Biochemistry & Molecular Biology and/or Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - David C Schriemer
- Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Departments of Biochemistry & Molecular Biology and/or Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada
| | - Zachary D Nagel
- Harvard University, School of Public Health, Boston, MA, 02115, USA
| | - Haico van Attikum
- Department of Human Genetics, Leiden University Medical Center, Einthovenweg 20, 2333 ZC, Leiden, The Netherlands
| | - Aaron A Goodarzi
- Robson DNA Science Centre, Arnie Charbonneau Cancer Institute, Departments of Biochemistry & Molecular Biology and/or Oncology, Cumming School of Medicine, University of Calgary, Calgary, AB, T2N 4N1, Canada.
| |
Collapse
|
7
|
Liebscher S, Koi L, Löck S, Muders MH, Krause M. The HIV protease and PI3K/Akt inhibitor nelfinavir does not improve the curative effect of fractionated irradiation in PC-3 prostate cancer in vitro and in vivo. Clin Transl Radiat Oncol 2017; 2:7-12. [PMID: 29657993 PMCID: PMC5893532 DOI: 10.1016/j.ctro.2016.12.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 12/12/2016] [Accepted: 12/13/2016] [Indexed: 11/16/2022] Open
Abstract
Background Radiotherapy has a high curative potential in localized prostate cancer, however, there are still patients with locally advanced tumours who face a considerable risk of recurrence. Radiosensitization using molecular targeted drugs could help to optimize treatment for this high-risk group. The PI3K/Akt pathway is overexpressed in many prostate cancers and is correlated to radioresistance. Nelfinavir, an HIV protease inhibitor (HPI), was found to block this pathway and to radiosensitize cancer cells of different origin. This is the first study examining the effect of nelfinavir in combination with irradiation on prostate cancer cell survival in vitro as well as on growth time and local tumour control in vivo. Methods The in vitro effect of nelfinavir on radioresponse of PC-3 was tested by colony formation assay with 10 μM nelfinavir. In vivo, the effect of nelfinavir alone and in combination with irradiation was tested in nude mice carrying PC-3 xenografts. For evaluating tumour growth time, mice were treated with 80 mg nelfinavir/kg body weight, daily at 5 days per week over 6 weeks. Simultaneous irradiation with 30 fractions and total doses between 30 and 120 Gy was applied to calculate local tumour control for day 180 after treatment. Results Nelfinavir inhibited Akt phosphorylation at Ser473 and showed a minor but significant effect on clonogenic cell survival in vitro with slightly higher cell survival rates after combined treatment. The treatment of PC-3 xenografts with nelfinavir alone led to no significant increase of tumour growth time and no improvement of local tumour control. Conclusions Despite promising growth delay effects of nelfinavir in other tumour models and first clinical applications of this drug as anti-cancer agent, PC-3 prostate cancer cells express no or only minor sensitivity to nelfinavir treatment alone and no radiosensitizing effect in vitro or in vivo.
Collapse
Affiliation(s)
- Steffi Liebscher
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Department of Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Lydia Koi
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology, Germany
| | - Steffen Löck
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Michael H Muders
- Institute of Pathology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany
| | - Mechthild Krause
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden and Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Department of Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology, Germany.,German Cancer Consortium (DKTK), Dresden and German Cancer Research Center (DKFZ) Heidelberg, Germany.,National Center for Tumour Diseases (NCT) Dresden, Germany
| |
Collapse
|
8
|
Wang Y, Guan H, Xie DF, Xie Y, Liu XD, Wang Q, Sui L, Song M, Zhang H, Zhou J, Zhou PK. Proteomic Analysis Implicates Dominant Alterations of RNA Metabolism and the Proteasome Pathway in the Cellular Response to Carbon-Ion Irradiation. PLoS One 2016; 11:e0163896. [PMID: 27711237 PMCID: PMC5053480 DOI: 10.1371/journal.pone.0163896] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 09/18/2016] [Indexed: 12/25/2022] Open
Abstract
Radiotherapy with heavy ions is considered advantageous compared to irradiation with photons due to the characteristics of the Braggs peak and the high linear energy transfer (LET) value. To understand the mechanisms of cellular responses to different LET values and dosages of heavy ion radiation, we analyzed the proteomic profiles of mouse embryo fibroblast MEF cells exposed to two doses from different LET values of heavy ion 12C. Total proteins were extracted from these cells and examined by Q Exactive with Liquid Chromatography (LC)—Electrospray Ionization (ESI) Tandem MS (MS/MS). Using bioinformatics approaches, differentially expressed proteins with 1.5 or 2.0-fold changes between different dosages of exposure were compared. With the higher the dosage and/or LET of ion irradiation, the worse response the cells were in terms of protein expression. For instance, compared to the control (0 Gy), 771 (20.2%) proteins in cells irradiated at 0.2 Gy of carbon-ion radiation with 12.6 keV/μm, 313 proteins (8.2%) in cells irradiated at 2 Gy of carbon-ion radiation with 12.6 keV/μm, and 243 proteins (6.4%) in cells irradiated at 2 Gy of carbon-ion radiation with 31.5 keV/μm exhibited changes of 1.5-fold or greater. Gene ontology (GO) analysis, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, Munich Information Center for Protein Sequences (MIPS) analysis, and BioCarta analysis all indicated that RNA metabolic processes (RNA splicing, destabilization and deadenylation) and proteasome pathways may play key roles in the cellular response to heavy-ion irradiation. Proteasome pathways ranked highest among all biological processes associated with heavy carbon-ion irradiation. In addition, network analysis revealed that cellular pathways involving proteins such as Col1a1 and Fn1 continued to respond to high dosages of heavy-ion irradiation, suggesting that these pathways still protect cells against damage. However, pathways such as those involving Ikbkg1 responded better at lower dosages than at higher dosages, implying that cell damage would occur when the networks involving these proteins stop responding. Our investigation provides valuable proteomic information for elucidating the mechanism of biological effects induced by carbon ions in general.
Collapse
Affiliation(s)
- Yu Wang
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiation Biology, Beijing Institute of Radiation Medicine, Beijing, China
| | - Hua Guan
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiation Biology, Beijing Institute of Radiation Medicine, Beijing, China
| | - Da-Fei Xie
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiation Biology, Beijing Institute of Radiation Medicine, Beijing, China
| | - Yi Xie
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Xiao-Dan Liu
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiation Biology, Beijing Institute of Radiation Medicine, Beijing, China
| | - Qi Wang
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiation Biology, Beijing Institute of Radiation Medicine, Beijing, China
| | - Li Sui
- China Institute of Atomic Energy, Beijing 102413, China
| | - Man Song
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiation Biology, Beijing Institute of Radiation Medicine, Beijing, China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, School of Radiation Medicine and Protection, Soochow University, Suzhou, China
| | - Hong Zhang
- Department of Heavy Ion Radiation Medicine, Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Jianhua Zhou
- iBioinfo Groups, Lexington, Massachusetts 02421, United States of America
- Department of Neuroregeneration, Nantong University, Nantong, China
- * E-mail: (PKZ); (JZ)
| | - Ping-Kun Zhou
- Department of Radiation Toxicology and Oncology, Beijing Key Laboratory for Radiation Biology, Beijing Institute of Radiation Medicine, Beijing, China
- Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, School of Radiation Medicine and Protection, Soochow University, Suzhou, China
- * E-mail: (PKZ); (JZ)
| |
Collapse
|
9
|
Shi HM, Ding KK, Zhou PK, Guo DM, Chen D, Li YS, Zhao CL, Zhao CC, Zhang X. Radiation-induced expression of IER5 is dose-dependent and not associated with the clinical outcomes of radiotherapy in cervical cancer. Oncol Lett 2016; 11:1309-1314. [PMID: 26893736 PMCID: PMC4734294 DOI: 10.3892/ol.2016.4086] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 10/30/2015] [Indexed: 11/08/2022] Open
Abstract
This study aimed to investigate the expression of the immediate-early response 5 (IER5) gene in cervical cancer tissues and explore the association between the expression of IER5 and the clinical outcomes of radiotherapy. We collected specimens by surgery or biopsy and obtained 53 specimens from tissues after radiotherapy and 16 specimens from tissues before radiotherapy. Immunohistochemistry and western blotting were used to assess the protein expression levels of IER5. Quantitative polymerase chain reaction (qPCR) was performed to assess the mRNA expression levels of IER5. The protein and mRNA expression levels of IER5 in cervical cancer patients treated with radiation doses ≥20 Gy were significantly higher than in those treated with radiation doses <20 Gy (P<0.05) and before treatment with radiotherapy. Moreover, the expression of IER5 was significantly positively correlated with the radiation dose (immunohistochemistry: r=0.548, P=0.019; qPCR: r=0.671, P=0.002; western blotting: r=0.573, P<0.0001). Radiotherapy induced the upregulated expression of IER5 and this was dependent on the radiation dose. However, the radiation-induced expression of IER5 was not associated with the clinical outcomes of radiotherapy in cervical cancer.
Collapse
Affiliation(s)
- Hai-Min Shi
- Department of Gynaecology, Liaoning Cancer Hospital and Institute, Shenyang, Liaoning 110042, P.R. China
| | - Ku-Ke Ding
- National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing 100088, P.R. China
| | - Ping-Kun Zhou
- Department of Radiation Toxicology and Oncology, Beijing Institute of Radiation Medicine, Beijing 100850, P.R. China
| | - Dong-Mei Guo
- Department of Gynaecology, Liaoning Cancer Hospital and Institute, Shenyang, Liaoning 110042, P.R. China
| | - Dan Chen
- Department of Gynaecology, Liaoning Cancer Hospital and Institute, Shenyang, Liaoning 110042, P.R. China
| | - Yan-Sha Li
- Department of Gynaecology, Liaoning Cancer Hospital and Institute, Shenyang, Liaoning 110042, P.R. China
| | - Chun-Li Zhao
- Department of Gynaecology, Liaoning Cancer Hospital and Institute, Shenyang, Liaoning 110042, P.R. China
| | - Chen-Chen Zhao
- Department of Gynaecology, Liaoning Cancer Hospital and Institute, Shenyang, Liaoning 110042, P.R. China
| | - Xin Zhang
- Department of Gynaecology, Liaoning Cancer Hospital and Institute, Shenyang, Liaoning 110042, P.R. China
| |
Collapse
|
10
|
MUKHERJEE SANJAY, SAINIS KB, DEOBAGKAR DEEPTID. F1 hybrids of BALB/c and C57BL/6 mouse strains respond differently to low-dose ionizing radiation exposure. J Genet 2014; 93:667-82. [DOI: 10.1007/s12041-014-0422-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
11
|
Stanley FKT, Moore S, Goodarzi AA. CHD chromatin remodelling enzymes and the DNA damage response. Mutat Res 2013; 750:31-44. [PMID: 23954449 DOI: 10.1016/j.mrfmmm.2013.07.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2013] [Revised: 07/22/2013] [Accepted: 07/26/2013] [Indexed: 01/08/2023]
Abstract
The protein and DNA complex known as chromatin is a dynamic structure, adapting to alter the spatial arrangement of genetic information within the nucleus to meet the ever changing demands of life. Following decades of research, a dizzying array of regulatory factors is now known to control the architecture of chromatin at nearly every level. Amongst these, ATP-dependent chromatin remodelling enzymes play a key role, required for the establishment, maintenance and re-organization of chromatin through their ability to adjust the contact points between DNA and histones, the spacing between individual nucleosomes and the over-arching chromatin superstructure. Utilizing energy from ATP hydrolysis, these enzymes serve as the gatekeepers of genomic access and are essential for transcriptional regulation, DNA replication and cell division. In recent years, a vital role in DNA Double Strand Break (DSB) repair has emerged, particularly within complex chromatin environments such as heterochromatin, or regions undergoing energetic transactions such as transcription or DNA replication. Here, we will provide an overview of what is understood about ATP-dependent chromatin remodelling enzymes in the context of the DNA damage response. We will first touch upon all four major chromatin remodelling enzyme families and then focus chiefly on the nine members of the Chromodomain, Helicase, DNA-binding (CHD) family, particularly CHD3, CHD4, CHD5 and CHD6. These four proteins have established and emerging roles in DNA repair, the oxidative stress response, the maintenance of genomic stability and/or cancer prevention.
Collapse
Affiliation(s)
- Fintan K T Stanley
- Southern Alberta Cancer Research Institute, Department of Biochemistry and Molecular Biology and Department of Oncology, University of Calgary, Calgary, Alberta T2N 4N1, Canada
| | | | | |
Collapse
|
12
|
Dos Santos SC, Teixeira MC, Cabrito TR, Sá-Correia I. Yeast toxicogenomics: genome-wide responses to chemical stresses with impact in environmental health, pharmacology, and biotechnology. Front Genet 2012; 3:63. [PMID: 22529852 PMCID: PMC3329712 DOI: 10.3389/fgene.2012.00063] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2012] [Accepted: 04/03/2012] [Indexed: 01/20/2023] Open
Abstract
The emerging transdisciplinary field of Toxicogenomics aims to study the cell response to a given toxicant at the genome, transcriptome, proteome, and metabolome levels. This approach is expected to provide earlier and more sensitive biomarkers of toxicological responses and help in the delineation of regulatory risk assessment. The use of model organisms to gather such genomic information, through the exploitation of Omics and Bioinformatics approaches and tools, together with more focused molecular and cellular biology studies are rapidly increasing our understanding and providing an integrative view on how cells interact with their environment. The use of the model eukaryote Saccharomyces cerevisiae in the field of Toxicogenomics is discussed in this review. Despite the limitations intrinsic to the use of such a simple single cell experimental model, S. cerevisiae appears to be very useful as a first screening tool, limiting the use of animal models. Moreover, it is also one of the most interesting systems to obtain a truly global understanding of the toxicological response and resistance mechanisms, being in the frontline of systems biology research and developments. The impact of the knowledge gathered in the yeast model, through the use of Toxicogenomics approaches, is highlighted here by its use in prediction of toxicological outcomes of exposure to pesticides and pharmaceutical drugs, but also by its impact in biotechnology, namely in the development of more robust crops and in the improvement of yeast strains as cell factories.
Collapse
Affiliation(s)
- Sandra C Dos Santos
- Institute for Biotechnology and Bioengineering, Centre for Biological and Chemical Engineering, Instituto Superior Técnico, Technical University of Lisbon Lisbon, Portugal
| | | | | | | |
Collapse
|
13
|
Rajagopalan S, Nepa J, Venkatachalam S. Chromodomain helicase DNA-binding protein 2 affects the repair of X-ray and UV-induced DNA damage. ENVIRONMENTAL AND MOLECULAR MUTAGENESIS 2012; 53:44-50. [PMID: 22223433 DOI: 10.1002/em.20674] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 07/12/2011] [Accepted: 07/13/2011] [Indexed: 05/31/2023]
Abstract
Eukaryotic cells have evolved a variety of parallel and redundant DNA damage response pathways that function in a coordinated fashion to prevent the fixation of DNA damage as mutations. Despite the wealth of knowledge on DNA damage signaling on downstream cellular events, the mechanisms of DNA damage recognition, DNA repair as well as DNA damage signaling in the context of chromatin is poorly understood. Chromodomain helicase DNA-binding proteins (CHD) belong to a group of highly conserved chromatin remodeling proteins that are implicated in regulation of transcription. In an effort to understand the physiological role of one of the CHD members in a mammalian model system, we developed a mutant mouse model for the Chd2 gene. The Chd2 mutant mice are highly susceptible to spontaneous lymphoid tumor formation. In this study, we present evidence that the Chd2 mutant cells are defective in their ability to repair DNA damage induced by ionizing and ultraviolet radiation. Consistent with the role of Chd2 in regulating DNA damage responses, the Chd2 mutant cells are also sensitive to DNA damaging agents in clonogenic assays. In summary, our data suggest that the Chd2 protein is involved in regulating the DNA damage responses at the chromatin level.
Collapse
Affiliation(s)
- Sangeetha Rajagopalan
- Department of Biochemistry and Cellular and Molecular Biology, University of Tennessee, Knoxville, Tennessee, USA
| | | | | |
Collapse
|
14
|
Transcriptional repression of Cdc25B by IER5 inhibits the proliferation of leukemic progenitor cells through NF-YB and p300 in acute myeloid leukemia. PLoS One 2011; 6:e28011. [PMID: 22132193 PMCID: PMC3223216 DOI: 10.1371/journal.pone.0028011] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Accepted: 10/29/2011] [Indexed: 11/23/2022] Open
Abstract
The immediately-early response gene 5 (IER5) has been reported to be induced by γ-ray irradiation and to play a role in the induction of cell death caused by radiation. We previously identified IER5 as one of the 2,3,4-tribromo-3-methyl-1-phenylphospholane 1-oxide (TMPP)-induced transcriptional responses in AML cells, using microarrays that encompassed the entire human genome. However, the biochemical pathway and mechanisms of IER5 function in regulation of the cell cycle remain unclear. In this study, we investigated the involvement of IER5 in the cell cycle and in cell proliferation of acute myeloid leukemia (AML) cells. We found that the over-expression of IER5 in AML cell lines and in AML-derived ALDHhi (High Aldehyde Dehydrogenase activity)/CD34+ cells inhibited their proliferation compared to control cells, through induction of G2/M cell cycle arrest and a decrease in Cdc25B expression. Moreover, the over-expression of IER5 reduced colony formation of AML-derived ALDHhi/CD34+ cells due to a decrease in Cdc25B expression. In addition, over-expression of Cdc25B restored TMPP inhibitory effects on colony formation in IER5-suppressed AML-derived ALDHhi/CD34+ cells. Furthermore, the IER5 reduced Cdc25B mRNA expression through direct binding to Cdc25B promoter and mediated its transcriptional attenuation through NF-YB and p300 transcriptinal factors. In summary, we found that transcriptional repression mediated by IER5 regulates Cdc25B expression levels via the release of NF-YB and p300 in AML-derived ALDHhi/CD34+ cells, resulting in inhibition of AML progenitor cell proliferation through modulation of cell cycle. Thus, the induction of IER5 expression represents an attractive target for AML therapy.
Collapse
|
15
|
Wang Z, Huang CM, Deng Q, Zeng H, Wang X, Zhang S, Bi F, Tang QL, Zhong RM, Li AJ, He YB, Chen N, Li ZP, Wang W. Effects of the proapoptotic regulator Bcl2/adenovirus EIB 19 kDa-interacting protein 3 on radiosensitivity of cervical cancer. Cancer Biother Radiopharm 2011; 26:279-86. [PMID: 21711117 DOI: 10.1089/cbr.2010.0898] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
PURPOSE Bcl2/adenovirus EIB 19 kDa-interacting protein 3 (BNIP3) is a proapoptotic member of the Bcl-2 family. To address its potential as a therapeutic target for radiosensitization, this study investigated the effect of Bnip3 expression on radiosensitivity of cervical cancer in vitro and in vivo. MATERIALS AND METHODS In vitro: A plasmid expressing the BNIP3 gene was transfected into human cervical cancer HeLa cells using Lipofectamine(2000), and western blot and immunohistochemistry analysis were performed to evaluate the expression of BNIP3 in transfected cells. The effects on radiation-induced apoptosis were investigated using a clone formation assay and flow cytometry. In vivo: A total of 6 × 10⁶ HeLa cells were subcutaneously inoculated into the dorsal flank of nude mice, and plasmids expressing the BNIP3 gene were injected into the mice via the tail vein. Tumor volume was calculated, and immunohistochemistry was used to detect the expression of BNIP3 in tumor cells. TUNEL assays were performed to determine the apoptosis rates in tumor tissues. RESULTS Transfection with the recombinant BNIP3 plasmid increased expression of the Bnip3 protein in tumor cells. This apoptosis regulator significantly decreased the viability of cells (p < 0.01) and increased the apoptosis rates (p < 0.01) both in vitro and in vivo. The antitumor effect of radiotherapy was enhanced by overexpression of BNIP3, as revealed by tumor growth curve analysis. CONCLUSIONS Radiosensitization in human cervical cancer cells was observed after treatment with the recombinant BNIP3 plasmid in vitro and in vivo. Results suggested that BNIP3 may play a role in enhancement of radiotherapy efficiency, and its expression may have a synergistic effect on radiation treatments.
Collapse
Affiliation(s)
- Zi Wang
- Department of Radiation Oncology, Cancer Center of West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
16
|
Filiano AN, Fathallah-Shaykh HM, Fiveash J, Gage J, Cantor A, Kharbanda S, Johnson MR. Gene expression analysis in radiotherapy patients and C57BL/6 mice as a measure of exposure to ionizing radiation. Radiat Res 2011; 176:49-61. [PMID: 21361780 DOI: 10.1667/rr2419.1] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Dose assessment after radiological disasters is imperative to decrease mortality through rationally directed medical intervention. Our goal was to identify biomarkers capable of qualitative (nonirradiated/irradiated) and/or quantitative (dose) assessment of radiation exposure. Using real-time quantitative PCR, biodosimetry genes were identified in blood samples from cancer patients undergoing total-body irradiation. Time- (5, 12, 23, 48 h) and dose- (0-8 Gy) dependent changes in gene expression were examined in C57BL/6 mice. A training set was used to derive weighted voting classification algorithms (nonirradiated/irradiated) and continuous regression (dose assessment) models that were tested in a separate validation set of mice. Of eight biodosimetry genes identified in cancer patients ( ACTA2 , BBC3 , CCNG1 , CDKN1A , GADD45A , MDK , SERPINE1 , Tnfrsf10b ), expression of BBC3 , CCNG1 , CDKN1A , SERPINE1 and Tnfrsf10b was significantly (P < 0.05) increased in irradiated mice. CCNG1 and CDKN1A expression segregated irradiated mice from controls with an accuracy, specificity and sensitivity of 96.3, 100.0 and 94.4%, respectively, at 48 h. Multiple linear regression analysis predicted doses for the 0-, 1-, 2-, 4-, 6- and 8-Gy treatment groups as 0.0 ± 0.2, 1.6 ± 1.0, 2.9 ± 1.4, 5.1 ± 2.0, 5.3 ± 0.7 and 10.5 ± 5.6 Gy, respectively. These results suggest that gene expression analysis could be incorporated into biodosimetry protocols for qualitative and quantitative assessment of radiation exposure.
Collapse
Affiliation(s)
- Ashley N Filiano
- Department of Pharmacology and Toxicology, University of Alabama at Birmingham, AL 35294, USA
| | | | | | | | | | | | | |
Collapse
|
17
|
Ho JN, Kang GY, Lee SS, Kim J, Bae IH, Hwang SG, Um HD. Bcl-XL and STAT3 mediate malignant actions of gamma-irradiation in lung cancer cells. Cancer Sci 2010; 101:1417-23. [PMID: 20331635 PMCID: PMC11159096 DOI: 10.1111/j.1349-7006.2010.01552.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2009] [Revised: 02/06/2010] [Accepted: 02/24/2010] [Indexed: 12/25/2022] Open
Abstract
Previous reports suggest that, in addition to its therapeutic effects, ionizing radiation (IR) increases the invasiveness of surviving cancer cells. Here, we demonstrate that this activity of IR in lung cancer cells is mediated by a signaling pathway involving p38 kinase, phosphoinositide 3-kinase, Akt, and matrix metalloproteinase (MMP-2). The invasion-promoting doses of IR also increased and reduced the levels of vimentin and E-cadherin, respectively, both of which are markers for the epithelial-mesenchymal transition (EMT). Interestingly, all of these malignant actions of IR were mimicked by the overexpression of Bcl-X(L), a pro-survival member of the Bcl-2 family, in lung cancer cells. Moreover, both RNA and protein levels of Bcl-X(L) were elevated upon irradiation of the cells, and the prevention of this event using small-interfering RNAs of Bcl-X(L) reduced the ability of IR to promote invasion signals and EMT-associated events. This suggests that Bcl-X(L) functions as a signaling mediator of the malignant effects of IR. It was also demonstrated that IR enhances signal transducer and activator of transcription 3 (STAT3) phosphorylation, and the reduction of STAT3 levels via RNA interference prevented IR-induced Bcl-X(L) accumulation, and thus all the tested Bcl-X(L)-dependent events. Overall, the data suggest that IR induces Bcl-X(L) accumulation via STAT3, which then promotes cancer cell invasion and EMT-associated markers. Our findings demonstrate a novel function of Bcl-X(L) in cancer, and also advance our understanding of the malignant actions of IR significantly.
Collapse
Affiliation(s)
- Jin-Nyoung Ho
- Korea Institute of Radiological and Medical Sciences, Seoul, Korea
| | | | | | | | | | | | | |
Collapse
|
18
|
Yatagai F, Sugasawa K, Enomoto S, Honma M. An approach to estimate radioadaptation from DSB repair efficiency. JOURNAL OF RADIATION RESEARCH 2009; 50:407-413. [PMID: 19680010 DOI: 10.1269/jrr.09050] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In this review, we would like to introduce a unique approach for the estimation of radioadaptation. Recently, we proposed a new methodology for evaluating the repair efficiency of DNA double-strand breaks (DSB) using a model system. The model system can trace the fate of a single DSB, which is introduced within intron 4 of the TK gene on chromosome 17 in human lymphoblastoid TK6 cells by the expression of restriction enzyme I-SceI. This methodology was first applied to examine whether repair of the DSB (at the I-SceI site) can be influenced by low-dose, low-dose rate gamma-ray irradiation. We found that such low-dose IR exposure could enhance the activity of DSB repair through homologous recombination (HR). HR activity was also enhanced due to the pre-IR irradiation under the established conditions for radioadaptation (50 mGy X-ray-6 h-I-SceI treatment). Therefore, radioadaptation might account for the reduced frequency of homozygous loss of heterozygosity (LOH) events observed in our previous experiment (50 mGy X-ray-6 h-2 Gy X-ray). We suggest that the present evaluation of DSB repair using this I-SceI system, may contribute to our overall understanding of radioadaptation.
Collapse
Affiliation(s)
- Fumio Yatagai
- Metallomics Imaging Research Unit, Center for Molecular Imaging Science, The Institute of Physical and Chemical Research (RIKEN), Saitama, Japan.
| | | | | | | |
Collapse
|
19
|
Ding KK, Shang ZF, Hao C, Xu QZ, Shen JJ, Yang CJ, Xie YH, Qiao C, Wang Y, Xu LL, Zhou PK. Induced expression of the IER5 gene by gamma-ray irradiation and its involvement in cell cycle checkpoint control and survival. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2009; 48:205-213. [PMID: 19238419 DOI: 10.1007/s00411-009-0213-4] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2008] [Accepted: 02/02/2009] [Indexed: 05/27/2023]
Abstract
The immediate-early response gene 5 (IER5) was previously shown, using microarray analysis, to be upregulated by ionizing radiation. Here we further characterized the dose- and time-dependency of radiation-induced expression of IER5 at doses from 0.5 to 15 Gy by quantitative real-time PCR analyses in HeLa cells and human lymphoblastoid AHH-1 cells. A radiation-induced increase in the IER5 mRNA level was evident 2 h after irradiation with 2 Gy in both cell lines. In AHH-1 cells the expression reached a peak at 4 h and then quickly returned to the control level, while in HeLa cells the expression only remained increased for a short period of time at around 2 h after irradiation before returning to the control. After high-dose irradiation (10 Gy), the induction of the IER5 expression was lower and delayed in AHH-1 cells as compared with 2-Gy irradiated cells. In HeLa cells, at this dose, two peaks of increased expression were observed 2 h and 12-24 h post-irradiation, respectively. RNA interference technology was employed to silence the IER5 gene in HeLa cells. siRNA-mediated suppression of IER5 resulted in an increased proliferation of HeLa cells. Cell growth and survival analyses demonstrated that suppression of IER5 significantly increased the radioresistance of HeLa cells to radiation doses of up to 6 Gy, but barely affected the sensitivity of cells at 8 Gy. Moreover, suppression of IER5 potentiated radiation-induced arrest at the G2-M transition and led to an increase in the fraction of S phase cells. Taken together, we propose that the early radiation-induced expression of IER5 affects the radiosensitivity via disturbing radiation-induced cell cycle checkpoints.
Collapse
Affiliation(s)
- Ku-Ke Ding
- Biomedical Engineering School, Capital Medical University, Beijing, People's Republic of China
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Fachin AL, Mello SS, Sandrin-Garcia P, Junta CM, Donadi EA, Passos GAS, Sakamoto-Hojo ET. Gene expression profiles in human lymphocytes irradiated in vitro with low doses of gamma rays. Radiat Res 2008; 168:650-65. [PMID: 18088177 DOI: 10.1667/rr0487.1] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2005] [Accepted: 07/26/2007] [Indexed: 11/03/2022]
Abstract
The molecular mechanisms underlying responses to low radiation doses are still unknown, especially in normal lymphocytes, despite the evidence suggesting specific changes that may characterize cellular responses. Our purpose was to analyze gene expression profiles by DNA microarrays in human lymphocytes after in vitro irradiation (10, 25 and 50 cGy) with gamma rays. A cytogenetic analysis was also carried out for different radiation doses. G 0 lymphocytes were irradiated and induced to proliferate for 48 h; then RNA samples were collected for gene expression analysis. ANOVA was applied to data obtained in four experiments with four healthy donors, followed by SAM analysis and hierarchical clustering. For 10, 25 and 50 cGy, the numbers of significantly (FDR <or= 0.05) modulated genes were 86, 130 and 142, respectively, and 25, 35 and 33 genes were exclusively modulated for each dose, respectively. We found CYP4X1, MAPK10 and ATF6 (10 cGy), DUSP16 and RAD51L1 (25 cGy), and RAD50, REV3L and DCLRE1A (50 cGy). A set of 34 significant genes was common for all doses; while SERPINB2 and C14orf104 were up-regulated, CREB3L2, DDX49, STK25 and XAB2 were down-regulated. Chromosome damage was significantly induced for doses >or=10 cGy (total aberrations) and >or=50 cGy (dicentrics/ rings). Therefore, low to moderate radiation doses induced qualitative and/or quantitative differences and similarities in transcript profiles, reflecting the type and extent of DNA lesions. The main biological processes associated with modulated genes were metabolism, stress response/DNA repair, cell growth/differentiation, and transcription regulation. The results indicate a potential risk to humans regarding the development of genetic instability and acquired diseases.
Collapse
Affiliation(s)
- Ana L Fachin
- Departamento de Genética e, Universidade de São Paulo, Ribeirao Preto, SP, Brazil
| | | | | | | | | | | | | |
Collapse
|
21
|
Amundson SA. Functional genomics in radiation biology: a gateway to cellular systems-level studies. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2008; 47:25-31. [PMID: 17973116 DOI: 10.1007/s00411-007-0140-1] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2007] [Accepted: 10/17/2007] [Indexed: 05/23/2023]
Abstract
Cells respond to ionizing radiation through an intricate network of interacting signaling cascades that are engaged in the regulation of diverse cellular functions, such as cell cycle arrest, DNA repair, and apoptosis. While changes in protein modification, activity, and sub-cellular localization may directly mediate these responses, alterations in gene expression also represent a central component of the pathways involved. Studies of altered gene expression have historically played an important role in elucidating the molecular mechanisms underlying cellular radiation response. In recent years, functional genomics approaches, such as microarray profiling, have been developed that can simultaneously monitor changes in gene expression across essentially the entire genome. However, analogous methods for global measurements of protein expression or modification have lagged behind. As global transcription profiling has become increasingly accessible, the quantity of information on gene expression responses to irradiation has increased dramatically. While many such experiments have provided improved insight into various aspects of radiation response, the diversity of experimental models and details of radiation dose, timing, and data analysis that have been employed means that no single consistent picture has emerged yet. More sophisticated methods for data analysis, data mining, and reverse engineering to reconstruct the underlying response pathways are continually being developed, and can extract additional value from profiling studies. As methods for the global study of other biomolecules become more routine, it will be important to integrate the results of radiation response profiling across multiple biological levels, and to build from simpler experimental systems toward more complex multi-cellular and in vivo systems. The future development of "integromic" models of radiation response should add substantially to the understanding gained from gene expression studies alone.
Collapse
Affiliation(s)
- Sally A Amundson
- Center for Radiological Research, Columbia University Medical Center, 630 W. 168th St., New York, NY 10032, USA.
| |
Collapse
|
22
|
Yatagai F, Umebayashi Y, Honma M, Sugasawa K, Takayama Y, Hanaoka F. Mutagenic radioadaptation in a human lymphoblastoid cell line. Mutat Res 2007; 638:48-55. [PMID: 17919664 DOI: 10.1016/j.mrfmmm.2007.08.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2007] [Revised: 08/15/2007] [Accepted: 08/22/2007] [Indexed: 11/18/2022]
Abstract
We investigated the mutagenic radioadaptive response of human lymphoblastoid TK6 cells by pretreating them with a low dose (5 cGy) of X-rays followed by a high (2 Gy) dose 6h later. Pretreatment reduced the 2-Gy-induced mutation frequency (MF) of the thymidine kinase (TK) gene (18.3 x 10(-6)) to 62% of the original level (11.4 x 10(-6)). A loss of heterozygosity (LOH) detection analysis applied to the isolated TK(-) mutants revealed the mutational events as non-LOH (resulting mostly from a point mutation in the TK gene), hemizygous LOH (resulting from a chromosomal deletion), or homozygous LOH (resulting from homologous recombination (HR) between chromosomes). For non-LOH events, pretreatment decreased the frequency to 27% of the original level (from 7.1 x 10(-6) to 1.9 x 10(-6)). cDNAs prepared from the non-LOH mutants revealed that the decrease was due mainly to the repression of base substitutions. The frequency of hemizygous LOH events, however, was not significantly altered by pretreatment. Mapping analysis of chromosome 17 demonstrated that the distribution and the extent of hemizygous LOH events were also not significantly influenced by pretreatment. For homozygous LOH events, pretreatment reduced the frequency to 61% of the original level (from 5.1 x 10(-6) to 3.1 x 10(-6)), reflecting an enhancement in HR repair of DNA double-strand breaks. Our findings suggest that the radioadaptive response in TK6 cells follows mainly from mutations at the base-sequence level, not the chromosome level.
Collapse
Affiliation(s)
- Fumio Yatagai
- Advanced Development and Support Center, The Institute of Physical and Chemical Research (RIKEN), Saitama 351-0198, Japan.
| | | | | | | | | | | |
Collapse
|
23
|
West CML, Elliott RM, Burnet NG. The genomics revolution and radiotherapy. Clin Oncol (R Coll Radiol) 2007; 19:470-80. [PMID: 17419040 DOI: 10.1016/j.clon.2007.02.016] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2007] [Accepted: 02/28/2007] [Indexed: 10/23/2022]
Abstract
The expansion of our knowledge through the Human Genome Project has been accompanied by the development of new high-throughput techniques, which provide extensive capabilities for the analysis of a large number of genes or the whole genome. These assays can be carried out in various clinical samples at the DNA (genome), RNA (transcriptome) or protein (proteome) level. There is a belief that this genomic revolution, i.e. sequencing of the human genome and developments in high-throughput technology, heralds a future of personalised medicine. For clinical oncology, this progress should increase the possibility of predicting individual patient responses to radiotherapy. This review highlights some of the work involving sparsely ionising radiation and the new technologies.
Collapse
Affiliation(s)
- C M L West
- Academic Radiation Oncology, University of Manchester, Christie Hospital NHS Trust, Manchester M20 4BX, UK.
| | | | | |
Collapse
|
24
|
Malone J, Ullrich R. Novel Radiation Response Genes Identified in Gene-Trapped MCF10A Mammary Epithelial Cells. Radiat Res 2007; 167:176-84. [PMID: 17390725 DOI: 10.1667/rr0656.1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We have used a gene-trapping strategy to screen human mammary epithelial cells for radiation response genes. Relative mRNA expression levels of five candidate genes in MCF10A cells were analyzed, both with and without exposure to radiation. In all five cases, the trapped genes were significantly down-regulated after radiation treatment. Sequence analysis of the fusion transcripts identified the trapped genes: (1) the human androgen receptor, (2) the uncharacterized DREV1 gene, which has known homology to DNA methyltransferases, (3) the human creatine kinase gene, (4) the human eukaryotic translation elongation factor 1 beta 2, and (5) the human ribosomal protein L27. All five genes were down-regulated significantly after treatment with varying doses of ionizing radiation (0.10 to 4.0 Gy) and at varying times (2-30 h after treatment). The genes were also analyzed in human fibroblast and lymphoblastoid cell lines to determine whether the radiation response being observed was cell-type specific. The results verified that the observed radiation response was not a cell-type-specific phenomenon, suggesting that the genes play essential roles in the radiation damage control pathways. This study demonstrates the potential of the gene-trap approach for the identification and functional analysis of novel radiation response genes.
Collapse
Affiliation(s)
- Jennifer Malone
- Department of Pathology, University of Colorado Health Sciences Center, Aurora, Colorado 80045-0508, USA.
| | | |
Collapse
|