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Mondal A, Bhattacharya A, Singh V, Pandita S, Bacolla A, Pandita RK, Tainer JA, Ramos KS, Pandita TK, Das C. Stress Responses as Master Keys to Epigenomic Changes in Transcriptome and Metabolome for Cancer Etiology and Therapeutics. Mol Cell Biol 2022; 42:e0048321. [PMID: 34748401 PMCID: PMC8773053 DOI: 10.1128/mcb.00483-21] [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] [Indexed: 11/20/2022] Open
Abstract
From initiation through progression, cancer cells are subjected to a magnitude of endogenous and exogenous stresses, which aid in their neoplastic transformation. Exposure to these classes of stress induces imbalance in cellular homeostasis and, in response, cancer cells employ informative adaptive mechanisms to rebalance biochemical processes that facilitate survival and maintain their existence. Different kinds of stress stimuli trigger epigenetic alterations in cancer cells, which leads to changes in their transcriptome and metabolome, ultimately resulting in suppression of growth inhibition or induction of apoptosis. Whether cancer cells show a protective response to stress or succumb to cell death depends on the type of stress and duration of exposure. A thorough understanding of epigenetic and molecular architecture of cancer cell stress response pathways can unveil a plethora of information required to develop novel anticancer therapeutics. The present view highlights current knowledge about alterations in epigenome and transcriptome of cancer cells as a consequence of exposure to different physicochemical stressful stimuli such as reactive oxygen species (ROS), hypoxia, radiation, hyperthermia, genotoxic agents, and nutrient deprivation. Currently, an anticancer treatment scenario involving the imposition of stress to target cancer cells is gaining traction to augment or even replace conventional therapeutic regimens. Therefore, a comprehensive understanding of stress response pathways is crucial for devising and implementing novel therapeutic strategies.
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Affiliation(s)
- Atanu Mondal
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
- Homi Bhaba National Institute, Mumbai, India
| | - Apoorva Bhattacharya
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
| | - Vipin Singh
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
- Homi Bhaba National Institute, Mumbai, India
| | - Shruti Pandita
- Division of Hematology and Medical Oncology, St. Louis University, St. Louis, Missouri, USA
| | - Albino Bacolla
- Department of Molecular and Cellular Oncology, University of Texas M.D. Anderson Cancer Center, Houston, Texas, USA
| | - Raj K. Pandita
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - John A. Tainer
- Department of Molecular and Cellular Oncology, University of Texas M.D. Anderson Cancer Center, Houston, Texas, USA
| | - Kenneth S. Ramos
- Center for Genomics and Precision Medicine, Texas A&M College of Medicine, Houston, Texas, USA
| | - Tej K. Pandita
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas, USA
- Center for Genomics and Precision Medicine, Texas A&M College of Medicine, Houston, Texas, USA
| | - Chandrima Das
- Biophysics and Structural Genomics Division, Saha Institute of Nuclear Physics, Kolkata, India
- Homi Bhaba National Institute, Mumbai, India
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Chamani F, Barnett I, Pyle M, Shrestha T, Prakash P. A Review of In Vitro Instrumentation Platforms for Evaluating Thermal Therapies in Experimental Cell Culture Models. Crit Rev Biomed Eng 2022; 50:39-67. [PMID: 36374822 DOI: 10.1615/critrevbiomedeng.2022043455] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Thermal therapies, the modulation of tissue temperature for therapeutic benefit, are in clinical use as adjuvant or stand-alone therapeutic modalities for a range of indications, and are under investigation for others. During delivery of thermal therapy in the clinic and in experimental settings, monitoring and control of spatio-temporal thermal profiles contributes to an increased likelihood of inducing desired bioeffects. In vitro thermal dosimetry studies have provided a strong basis for characterizing biological responses of cells to heat. To perform an accurate in vitro thermal analysis, a sample needs to be subjected to uniform heating, ideally raised from, and returned to, baseline immediately, for a known heating duration under ideal isothermal condition. This review presents an applications-based overview of in vitro heating instrumentation platforms. A variety of different approaches are surveyed, including external heating sources (i.e., CO2 incubators, circulating water baths, microheaters and microfluidic devices), microwave dielectric heating, lasers or the use of sound waves. We discuss critical heating parameters including temperature ramp rate (heat-up phase period), heating accuracy, complexity, peak temperature, and technical limitations of each heating modality.
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Affiliation(s)
- Faraz Chamani
- Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS, USA
| | - India Barnett
- Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS, USA
| | - Marla Pyle
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA
| | - Tej Shrestha
- Department of Anatomy and Physiology, College of Veterinary Medicine, Kansas State University, Manhattan, KS, USA; Nanotechnology Innovation Center of Kansas State (NICKS), Kansas State University, Manhattan, KS, USA
| | - Punit Prakash
- Department of Electrical and Computer Engineering, Kansas State University, Manhattan, KS 66506, USA
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Hannon G, Tansi FL, Hilger I, Prina‐Mello A. The Effects of Localized Heat on the Hallmarks of Cancer. ADVANCED THERAPEUTICS 2021. [DOI: 10.1002/adtp.202000267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Gary Hannon
- Nanomedicine and Molecular Imaging Group Trinity Translational Medicine Institute Dublin 8 Ireland
- Laboratory of Biological Characterization of Advanced Materials (LBCAM), Trinity Translational Medicine Institute Trinity College Dublin Dublin 8 Ireland
| | - Felista L. Tansi
- Department of Experimental Radiology, Institute of Diagnostic and Interventional Radiology Jena University Hospital—Friedrich Schiller University Jena Am Klinikum 1 07740 Jena Germany
| | - Ingrid Hilger
- Department of Experimental Radiology, Institute of Diagnostic and Interventional Radiology Jena University Hospital—Friedrich Schiller University Jena Am Klinikum 1 07740 Jena Germany
| | - Adriele Prina‐Mello
- Nanomedicine and Molecular Imaging Group Trinity Translational Medicine Institute Dublin 8 Ireland
- Laboratory of Biological Characterization of Advanced Materials (LBCAM), Trinity Translational Medicine Institute Trinity College Dublin Dublin 8 Ireland
- Advanced Materials and Bioengineering Research (AMBER) Centre, CRANN Institute Trinity College Dublin Dublin 2 Ireland
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Biotinylation by antibody recognition-a method for proximity labeling. Nat Methods 2017; 15:127-133. [PMID: 29256494 PMCID: PMC5790613 DOI: 10.1038/nmeth.4533] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 10/30/2017] [Indexed: 01/12/2023]
Abstract
Identification of protein-protein interactions is a major goal of biological research. Despite technical advances over the last two decades, important but still largely unsolved challenges include the high-throughput detection of interactions directly from primary tissue and the identification of interactors of insoluble proteins that form higher-order structures. We have developed a novel, proximity-based labeling approach that uses antibodies to guide biotin deposition onto adjacent proteins in fixed cells and primary tissues. We showed our method to be specific and sensitive by labeling a mitochondrial matrix protein. Next, we used this method to profile the dynamic interactome of lamin A/C in multiple cell and tissue types under various treatment conditions. The ability to detect proximal proteins and putative interactors in intact tissues, and to quantify changes caused by different conditions or in the presence of disease mutations, can provide a new window into cell biology and disease pathogenesis.
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Nakagawa Y, Kajihara A, Takahashi A, Murata AS, Matsubayashi M, Ito SS, Ota I, Nakagawa T, Hasegawa M, Kirita T, Ohnishi T, Mori E. BRCA2 protects mammalian cells from heat shock. Int J Hyperthermia 2017; 34:795-801. [PMID: 28891354 DOI: 10.1080/02656736.2017.1370558] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
PURPOSE Heat shock induces DNA double-strand breaks (DSBs) in mammalian cells. Mammalian cells are capable of repairing DSBs by utilising the homologous recombination (HR) pathway. Breast cancer susceptibility gene 2 (BRCA2) is known to regulate the HR pathway. Here, we investigate the role of BRCA2 in repairing DNA damage induced by heat shock. MATERIALS AND METHODS Chinese hamster lung fibroblast cell lines and human tongue squamous cell carcinoma SAS cells were used. RAD51 foci formation assay was used as an HR indicator. Heat sensitivity was analysed with colony forming assays. Phosphorylated histone H2AX (γH2AX) intensity, which correlates with the number of DSBs, was analysed with flow cytometry. RESULTS RAD51 foci appeared with heat shock, and the number of cells with RAD51 foci was maximal at about 4 h after heat shock. Heat-induced RAD51 foci co-localised with γH2AX foci. BRCA2-deficient cells were sensitive to heat when compared to their parental wild-type cells. Heat-induced γH2AX was higher in BRCA2-deficient cells compared to parental cells. In SAS cells, cells transfected with BRCA2-siRNA were more sensitive to heat than cells transfected with negative control siRNA. Apoptotic bodies increased in number more rapidly in BRCA2-siRNA transfected cells than in cells transfected with negative control siRNA when cells were observed at 48 h after a heat treatment. In addition, cells deficient in BRCA2 were incapable of activating heat-induced G2/M arrest. CONCLUSION BRCA2 has a protecting role against heat-induced cell death. BRCA2 might be a potential molecular target for hyperthermic cancer therapy.
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Affiliation(s)
- Yosuke Nakagawa
- a Department of Oral and Maxillofacial Surgery , Nara Medical University , Nara , Japan
| | - Atsuhisa Kajihara
- a Department of Oral and Maxillofacial Surgery , Nara Medical University , Nara , Japan
| | | | - Akiho S Murata
- c Department of Future Basic Medicine , Nara Medical University , Nara , Japan
| | - Masaya Matsubayashi
- c Department of Future Basic Medicine , Nara Medical University , Nara , Japan
| | - Soichiro S Ito
- a Department of Oral and Maxillofacial Surgery , Nara Medical University , Nara , Japan
| | - Ichiro Ota
- d Department of Otolaryngology - Head and Neck Surgery , Nara Medical University , Nara , Japan
| | - Takahiko Nakagawa
- c Department of Future Basic Medicine , Nara Medical University , Nara , Japan
| | - Masatoshi Hasegawa
- e Department of Radiation Oncology , Nara Medical University , Nara , Japan
| | - Tadaaki Kirita
- a Department of Oral and Maxillofacial Surgery , Nara Medical University , Nara , Japan
| | - Takeo Ohnishi
- e Department of Radiation Oncology , Nara Medical University , Nara , Japan
| | - Eiichiro Mori
- c Department of Future Basic Medicine , Nara Medical University , Nara , Japan
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Takahashi A, Mori E, Nakagawa Y, Kajihara A, Kirita T, Pittman DL, Hasegawa M, Ohnishi T. Homologous recombination preferentially repairs heat-induced DNA double-strand breaks in mammalian cells. Int J Hyperthermia 2016; 33:336-342. [PMID: 27776457 DOI: 10.1080/02656736.2016.1252989] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
PURPOSE Heat shock induces DNA double-strand breaks (DSBs), but the precise mechanism of repairing heat-induced damage is unclear. Here, we investigated the DNA repair pathways involved in cell death induced by heat shock. MATERIALS AND METHODS B02, a specific inhibitor of human RAD51 (homologous recombination; HR), and NU7026, a specific inhibitor of DNA-PK (non-homologous end-joining; NHEJ), were used for survival assays of human cancer cell lines with different p53-gene status. Mouse embryonic fibroblasts (MEFs) lacking Lig4 (NHEJ) and/or Rad54 (HR) were used for survival assays and a phosphorylated histone H2AX at Ser139 (γH2AX) assay. MEFs lacking Rad51d (HR) were used for survival assays. SPD8 cells were used to measure HR frequency after heat shock. RESULTS Human cancer cells were more sensitive to heat shock in the presence of B02 despite their p53-gene status, and the effect of B02 on heat sensitivity was specific to the G2 phase. Rad54-deficient MEFs were sensitive to heat shock and showed prolonged γH2AX signals following heat shock. Rad51d-deficient MEFs were also sensitive to heat shock. Moreover, heat shock-stimulated cells had increased HR. CONCLUSIONS The HR pathway plays an important role in the survival of mammalian cells against death induced by heat shock via the repair of heat-induced DNA DSBs.
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Affiliation(s)
| | - Eiichiro Mori
- b Department of Radiation Oncology , Nara Medical University , Nara, Japan
| | - Yosuke Nakagawa
- c Department of Oral and Maxillofacial Surgery , Nara Medical University , Nara, Japan
| | - Atsuhisa Kajihara
- c Department of Oral and Maxillofacial Surgery , Nara Medical University , Nara, Japan
| | - Tadaaki Kirita
- c Department of Oral and Maxillofacial Surgery , Nara Medical University , Nara, Japan
| | - Douglas L Pittman
- d Department of Drug Discovery and Biomedical Sciences, South Carolina College of Pharmacy , University of South Carolina , Columbia , SC , USA
| | - Masatoshi Hasegawa
- b Department of Radiation Oncology , Nara Medical University , Nara, Japan
| | - Takeo Ohnishi
- b Department of Radiation Oncology , Nara Medical University , Nara, Japan
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Oei AL, Vriend LEM, Crezee J, Franken NAP, Krawczyk PM. Effects of hyperthermia on DNA repair pathways: one treatment to inhibit them all. Radiat Oncol 2015; 10:165. [PMID: 26245485 PMCID: PMC4554295 DOI: 10.1186/s13014-015-0462-0] [Citation(s) in RCA: 177] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 07/13/2015] [Indexed: 12/03/2022] Open
Abstract
The currently available arsenal of anticancer modalities includes many DNA damaging agents that can kill malignant cells. However, efficient DNA repair mechanisms protect both healthy and cancer cells against the effects of treatment and contribute to the development of drug resistance. Therefore, anti-cancer treatments based on inflicting DNA damage can benefit from inhibition of DNA repair. Hyperthermia – treatment at elevated temperature – considerably affects DNA repair, among other cellular processes, and can thus sensitize (cancer) cells to DNA damaging agents. This effect has been known and clinically applied for many decades, but how heat inhibits DNA repair and which pathways are targeted has not been fully elucidated. In this review we attempt to summarize the known effects of hyperthermia on DNA repair pathways relevant in clinical treatment of cancer. Furthermore, we outline the relationships between the effects of heat on DNA repair and sensitization of cells to various DNA damaging agents.
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Affiliation(s)
- Arlene L Oei
- Laboratory for Experimental Oncology and Radiobiology (LEXOR), Center for Experimental and Molecular Medicine, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands. .,Department of Radiotherapy, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands.
| | - Lianne E M Vriend
- Van Leeuwenhoek Centre for Advanced Microscopy (LCAM)-AMC, Department of Cell Biology and Histology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands.
| | - Johannes Crezee
- Department of Radiotherapy, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands.
| | - Nicolaas A P Franken
- Laboratory for Experimental Oncology and Radiobiology (LEXOR), Center for Experimental and Molecular Medicine, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands. .,Department of Radiotherapy, Academic Medical Center, University of Amsterdam, 1105 AZ, Amsterdam, The Netherlands.
| | - Przemek M Krawczyk
- Van Leeuwenhoek Centre for Advanced Microscopy (LCAM)-AMC, Department of Cell Biology and Histology, Academic Medical Center, University of Amsterdam, Meibergdreef 15, 1105 AZ, Amsterdam, The Netherlands.
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8
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Eppink B, Krawczyk PM, Stap J, Kanaar R. Hyperthermia-induced DNA repair deficiency suggests novel therapeutic anti-cancer strategies. Int J Hyperthermia 2012; 28:509-17. [PMID: 22834701 DOI: 10.3109/02656736.2012.695427] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Local hyperthermia is an effective treatment modality to augment radio- and chemotherapy-based anti-cancer treatments. Although the effect of hyperthermia is pleotropic, recent experiments revealed that homologous recombination, a pathway of DNA repair, is directly inhibited by hyperthermia. The hyperthermia-induced DNA repair deficiency is enhanced by inhibitors of the cellular heat-shock response. Taken together, these results provide the rationale for the development of novel anti-cancer therapies that combine hyperthermia-induced homologous recombination deficiency with the systemic administration of drugs that specifically affect the viability of homologous recombination deficient cells and/or inhibit the heat-shock response, to locally sensitise cancer cells to DNA damaging agents.
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Affiliation(s)
- Berina Eppink
- Department of Cell Biology and Genetics, Cancer Genomics Centre, Erasmus Medical Centre, Rotterdam, The Netherlands
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Gerashchenko BI, Gooding G, Dynlacht JR. Hyperthermia alters the interaction of proteins of the Mre11 complex in irradiated cells. Cytometry A 2010; 77:940-52. [PMID: 21290468 PMCID: PMC3075327 DOI: 10.1002/cyto.a.20955] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2010] [Revised: 07/02/2010] [Accepted: 07/05/2010] [Indexed: 12/13/2022]
Abstract
Radiosensitization of mammalian cells by heat is believed to involve the inhibition of repair of DNA double-strand breaks (DSBs). The Mre11 complex (composed of Mre11, Rad50, and Nbs1) is involved in DSB repair and forms foci at sites of radiation-induced DSBs. Heat induces the translocation of a significant amount of Mre11, Rad50, and Nbs1 from the nucleus to the cytoplasm, but little is known about how heat affects the integrity of the proteins still remaining in nuclei, or alters kinetics of formation/disappearance of DNA repair foci in heated, irradiated cells. Here, we show that hyperthermia alters the interaction between proteins of the Mre11 complex in irradiated human melanoma cells and inhibits the formation of repair foci. At various times after X-irradiation and/or heating (2 h at 41.5 or 42.5 °C), the cells were fixed and stained for Mre11, Rad50, and Nbs1. Colocalization of proteins and formation and disappearance of nuclear foci in heated and/or irradiated cells, determined using confocal microscopy, were compared. In heated, irradiated cells, focus formation was inhibited for 2-8 h, and colocalization of the proteins of the Mre11 complex was reduced for 12-24 h post-treatment. Colocalization was recovered in irradiated cells within 24 h after heating at 41.5 °C, but was inhibited longer after heating at 42.5 °C. The decreased colocalization in heated, irradiated cells suggests that there is a decrease in protein interaction, and Mre11 complexes in nuclei disassemble after heating. Such changes could be involved, at least in part, in heat radiosensitization and inhibition of DSB repair. Also, the kinetics of disassembly and reassembly of Mre11 complexes appears to be dependent upon treatment temperature.
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Affiliation(s)
- Bogdan I. Gerashchenko
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Radiobiology and Ecology, R.E. Kavetsky Institute of Experimental Pathology, Oncology and Radiobiology, Kyiv 03022, Ukraine
| | - Gerirose Gooding
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
| | - Joseph R. Dynlacht
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA
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Chankova SG, Yurina NP, Dimova EG, Ermohina OV, Oleskina YP, Dimitrova MT, Bryant PE. Pretreatment with heat does not affect double-strand breaks DNA rejoining in Chlamydomonas reinhardtii. J Therm Biol 2009. [DOI: 10.1016/j.jtherbio.2009.06.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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11
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Umeda N, Matsumoto Y, Yin HL, Tomita M, Enomoto A, Morita A, Mizukoshi T, Sakai K, Hosoi Y, Suzuki N. Difference in the heat sensitivity of DNA‐dependent protein kinase activity among mouse, hamster and human cells. Int J Radiat Biol 2009; 79:671-80. [PMID: 14555350 DOI: 10.1080/09553000310001596959] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE To examine the heat sensitivity of DNA-dependent protein kinase (DNA-PK) activity in a variety of cultured mouse, hamster and human cell lines. MATERIALS AND METHODS Eight cell lines, which have been routinely used in our laboratory, were examined. Cells were heated at 44.0 +/- 0.05 degrees C and DNA-PK activity was measured by a DNA-pull-down assay followed by gel-electrophoresis. Cellular sensitivity to hyperthermia and/or X-ray was evaluated by a colony formation assay. RESULTS In mouse FSA1233 and FM3A cells, DNA-PK activity dropped to 15-16% of unheated control after 20 min of heating. In Chinese hamster V79 and CHO-K1 cells, kinase activity did not change appreciably after 20 min treatment but decreased to 60-70 and 22-23% after 40 or 60 min treatment, respectively. However, even after 180 min treatment, DNA-PK activity remained almost intact in human MOLT-4, MKN45 and A7 cells, and decreased only slightly in U937 cells. Hyperthermic radiosensitization was seen even in human cells but, as a trend, it was small compared with rodent cells. CONCLUSIONS The heat sensitivity of DNA-PK was clearly different among mouse, hamster and human cells. The results suggested a possibility that the role of DNA-PK inactivation in hyperthermic radiosensitization might be variable, depending on cells, and would reinforce the warning that the direct extrapolation of data from rodent cells might lead to overestimation of the effectiveness of hyperthermia on human cancer.
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Affiliation(s)
- N Umeda
- Department of Radiation Oncology, Graduate School of Medicine, University of Tokya, Hongo, Japan
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Chang WC, Wang YK, Liu PF, Tsai YF, Kong LR, Lin CK, Yang CH, Pan RL. Regulation of Ku gene promoters in Arabidopsis by hormones and stress. FUNCTIONAL PLANT BIOLOGY : FPB 2008; 35:265-280. [PMID: 32688782 DOI: 10.1071/fp07249] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Accepted: 04/29/2008] [Indexed: 06/11/2023]
Abstract
The Ku70/Ku80 heterodimer plays a crucial role in non-homologous end-joining during DNA repair, and is also involved in multiple cellular processes such as telomere maintenance, transcription, and apoptosis. In this study, we investigate the regulation of AtKu genes in higher plants. Promoters of the AtKu70 and AtKu80 were isolated from Arabidopsis and their activities characterised using GUS reporter constructs. AtKu promoter activities were relatively higher in hypocotyls and cotyledons upon germination and in stigma and siliques as well at their early developing stages. Furthermore, AtKu promoter activities could be enhanced by gibberellic acid, auxins, and jasmonic acid, but repressed by abscisic acid, salicylic acid, heat, drought and cold, respectively. Deletion analysis demonstrates minimal lengths of ~400 bp and 600 bp upstream of transcription start site for functional promoters of AtKu70 and AtKu80, respectively. Taken together, expressions of Ku genes are regulated both by developmental programs as well as by plant hormones and environmental stresses.
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Affiliation(s)
- Wen-Chi Chang
- Institute of Bioinformatics and Structural Biology, College of Life Sciences, National Tsing Hua University, Hsin-Chu 30013, Taiwan
| | - Yung-Kai Wang
- Institute of Bioinformatics and Structural Biology, College of Life Sciences, National Tsing Hua University, Hsin-Chu 30013, Taiwan
| | - Pei-Feng Liu
- Institute of Bioinformatics and Structural Biology, College of Life Sciences, National Tsing Hua University, Hsin-Chu 30013, Taiwan
| | - Yu-Fang Tsai
- Institute of Bioinformatics and Structural Biology, College of Life Sciences, National Tsing Hua University, Hsin-Chu 30013, Taiwan
| | - Lih-Ren Kong
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung 40227, Taiwan
| | - Chi-Kai Lin
- Institute of Bioinformatics and Structural Biology, College of Life Sciences, National Tsing Hua University, Hsin-Chu 30013, Taiwan
| | - Chang-Hsien Yang
- Graduate Institute of Biotechnology, National Chung Hsing University, Taichung 40227, Taiwan
| | - Rong-Long Pan
- Institute of Bioinformatics and Structural Biology, College of Life Sciences, National Tsing Hua University, Hsin-Chu 30013, Taiwan
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Liu PF, Wang YK, Chang WC, Chang HY, Pan RL. Regulation of Arabidopsis thaliana Ku genes at different developmental stages under heat stress. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2008; 1779:402-7. [PMID: 18515112 DOI: 10.1016/j.bbagrm.2008.05.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2007] [Revised: 05/05/2008] [Accepted: 05/05/2008] [Indexed: 11/17/2022]
Abstract
Ku, a heterodimeric protein consisting of 70- and 80-kDa subunits, is involved in many cellular processes, such as DNA replication, cell cycle regulation and heat shock response. Moreover, the expression of Arabidopsis thaliana Ku genes (AtKu) is modulated by certain plant hormones through several signal transduction pathways. This study investigated how AtKu are regulated by heat stress. AtKu expression in 3-week-old young seedlings was down-regulated by heat stress in a time-dependent manner, as examined using real-time quantitative PCR, GUS reporter systems, and western blotting analysis. Additionally, the heat-induced repression of AtKu was mediated through the abscisic acid (ABA) biosynthetic pathway, as shown by the reversal of AtKu suppression in the ABA biosynthesis mutant, aba3, and by an increase in the ABA level as analyzed by reverse-phase high performance liquid chromatography. Heat stress-induced regulation of AtKu repression also involved ethylene signaling, DNA repair pathways, and fatty acid synthesis. Furthermore, AtKu expression was repressed in stems, rosette leaves, and cauline leaves in 4-5-week-old plants under heat stress, whereas it remained unchanged in roots and primary inflorescence, indicating that heat differentially modulated AtKu expression in distinct tissues of Arabidopsis.
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Affiliation(s)
- Pei Feng Liu
- Department of Life Sciences and Institute of Bioinformatics and Structural Biology, National Tsing Hua University, Hsin Chu, Taiwan 30013, ROC
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Lupu A, Nevo E, Zamorzaeva I, Korol A. Ecological–genetic feedback in DNA repair in wild barley, Hordeum spontaneum. Genetica 2006; 127:121-32. [PMID: 16850218 DOI: 10.1007/s10709-005-2611-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2005] [Accepted: 08/31/2005] [Indexed: 02/05/2023]
Abstract
Regulation of genetic variation in natural populations is a problem of primary importance to evolutionary biology. In the reported study, the repair efficiency of double strand DNA breaks was compared in six wild barley accessions from Israeli natural populations of H. spontaneum: three from mesic populations (one from Maalot and two from Mount Meron, Upper Galilee) and three from xeric populations (one from Wadi Quilt in the Judean Desert and two from Sede Boqer, in the northern Negev Desert). Pulsed field gel electrophoresis was used to score double-strand breaks of DNA (DSBs) caused by methyl methanesulphonate (MMS) treatment. All six accessions were also tested for heat tolerance: four of these, three xeric and one mesic (from Maalot population), were scored as heat tolerant whereas both accessions from Mount Meron population displayed heat sensitivity. MMS caused a significant increase in the level of DSBs relative to the control in all accessions. The major questions were whether and how the efficiency of DNA repair after mutagenic treatment is affected by the environmental conditions and accession's adaptation to these conditions. Differences were found among the accessions in the repair pattern. Plants of two out of the four heat tolerant accessions did not manage to repair DNA neither at 25 degrees Celsius nor at 37 degrees Celsius. The remaining two heat tolerant accessions significantly repaired the breaks at 37 degrees Celsius, but not at 25 degrees Celsius. By contrast, plants of the two heat susceptible accessions significantly lowered the level of DSBs at 25 degrees Celsius but not at 37 degrees Celsius. Therefore, the accessions that proved capable to repair the induced damages in DNA at one of the two temperatures displayed a pattern that may imply the existence of a negative feedback mechanism in regulation of genetic variation. Such a dependence of DNA integrity on environment and genotype may serve an important factor for maintaining relatively high level of mutability without increasing the genetic load.
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Affiliation(s)
- Achsa Lupu
- Institute of Evolution, University of Haifa, Mount Carmel, Haifa, 31905, Israel
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Yin HL, Suzuki Y, Matsumoto Y, Tomita M, Furusawa Y, Enomoto A, Morita A, Aoki M, Yatagai F, Suzuki T, Hosoi Y, Ohtomo K, Suzuki N. Radiosensitization by hyperthermia in the chicken B-lymphocyte cell line DT40 and its derivatives lacking nonhomologous end joining and/or homologous recombination pathways of DNA double-strand break repair. Radiat Res 2004; 162:433-41. [PMID: 15447039 DOI: 10.1667/rr3239] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Hyperthermia has a radiosensitizing effect, which is one of the most important biological bases for its use in cancer therapy with radiation. Although the mechanism of this effect has not been clarified in molecular terms, possible involvement of either one or both of two major DNA double-strand break (DSB) repair pathways, i.e. nonhomologous end joining (NHEJ) and homologous recombination (HR), has been speculated. To test this possibility, we examined cells of the chicken B-lymphocyte cell line DT40 and its derivatives lacking NHEJ and/or HR: KU70(-/-), DNA-PKcs(-/-/-), RAD54(-/-) and KU70(-/-)/RAD54(-/-). Radiosensitization by hyperthermia could be seen in all of the mutants, including KU70(-/-)/RAD54(-/-), which lacked both NHEJ and HR. Therefore, radiosensitization by hyperthermia cannot be explained simply by its inhibitory effects, if any, on NHEJ and/or HR alone. However, in NHEJ-defective KU70(-/-) and DNA-PKcs(-/-/-), consisting of two subpopulations with distinct radiosensitivity, the radiosensitive subpopulation, which is considered to be cells in G(1) and early S, was not sensitized. Substantial sensitization was seen only in the radioresistant subpopulation, which is considered to be cells in late S and G(2), capable of repairing DSBs through HR. This observation did not exclude possible involvement of NHEJ in G(1) and early S phase and also suggested inhibitory effects of hyperthermia on HR. Thus partial contribution of NHEJ and HR in radiosensitization by hyperthermia, especially that depending on the cell cycle stage, remains to be considered.
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Affiliation(s)
- Hong Lan Yin
- Department of Radiation Research, Center for Disease Biology and Integrative Medicine, Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
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16
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Seno JD, Dynlacht JR. Intracellular redistribution and modification of proteins of the Mre11/Rad50/Nbs1 DNA repair complex following irradiation and heat-shock. J Cell Physiol 2004; 199:157-70. [PMID: 15039997 DOI: 10.1002/jcp.10475] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Mre11, Rad50, and Nbs1form a tight complex which is homogeneously distributed throughout the nuclei of mammalian cells. However, after irradiation, the Mre11/Rad50/Nbs1 (M/R/N) complex rapidly migrates to sites of double strand breaks (DSBs), forming foci which remain until DSB repair is complete. Mre11 and Rad50 play direct roles in DSB repair, while Nbs1 appears to be involved in damage signaling. Hyperthermia sensitizes mammalian cells to ionizing radiation. Radiosensitization by heat shock is believed to be mediated by an inhibition of DSB repair. While the mechanism of inhibition of repair by heat shock remains to be elucidated, recent reports suggest that the M/R/N complex may be a target for inhibition of DSB repair and radiosensitization by heat. We now demonstrate that when human U-1 melanoma cells are heated at 42.5 or 45.5 degrees C, Mre11, Rad50, and Nbs1 are rapidly translocated from the nucleus to the cytoplasm. Interestingly, when cells were exposed to ionizing radiation (12 Gy of X-rays) prior to heat treatment, the extent and kinetics of translocation were increased when nuclear and cytoplasmic fractions of protein were analyzed immediately after treatment. The kinetics of the translocation and subsequent relocalization back into the nucleus when cells were incubated at 37 degrees C from 30 min to 7 h following treatment were different for each protein, which suggests that the proteins redistribute independently. However, a significant fraction of the translocated proteins exist as a triple complex in the cytoplasm. Treatment with leptomycin B (LMB) inhibits the translocation of Mre11, Rad50, and Nbs1 to the cytoplasm, leading us to speculate that the relocalization of the proteins to the cytoplasm occurs via CRM1-mediated nuclear export. In addition, while Nbs1 is rapidly phosphorylated in the nuclei of irradiated cells and is critical for a normal DNA damage response, we have found that Nbs1 is rapidly phosphorylated in the cytoplasm, but not in the nucleus, of heated irradiated cells. The phosphorylation of cytoplasmic Nbs1, which cannot be inhibited by wortmannin, appears to be a unique post-translational modification in heated, irradiated cells, and coupled with our novel observations that Mre11, Rad50, and Nbs1 translocate to the cytoplasm, lend further support for a role of the M/R/N complex in thermal radiosensitization and inhibition of DSB repair.
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Affiliation(s)
- Joshua D Seno
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis 46202, USA
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17
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Dynlacht JR, Xu M, Pandita RK, Wetzel EA, Roti Roti JL. Effects of heat shock on the Mre11/Rad50/Nbs1 complex in irradiated or unirradiated cells. Int J Hyperthermia 2004; 20:144-56. [PMID: 15195509 DOI: 10.1080/02656730410001660634] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022] Open
Abstract
The mechanism by which hyperthermia sensitizes mammalian cells to ionizing radiation remains to be elucidated, but an overwhelming amount of circumstantial evidence suggests that heat radiosensitization might be mediated by inhibition of double-strand break repair, particularly after exposure of irradiated cells to heat treatments in excess of about 43 degrees C. In mammalian cells, double-strand break repair usually occurs via two pathways, non-homologous end-joining and homologous recombination. Several reports suggest a role for non-homologous end-joining in heat radiosensitization, while others implicate homologous recombination as a target. However, cell lines that are compromised in either the non-homologous end-joining or homologous recombination pathway are still capable of being radiosensitized, suggesting that heat affects both pathways. Indeed, several of the proteins involved in one or both of these pathways have been observed to undergo alterations or translocation after unirradiated or irradiated cells are exposed to heat shock. The work summarized in this review implicates proteins of the Mre11/Rad50/Nbs1 complex as targets for heat radiosensitization.
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Affiliation(s)
- J R Dynlacht
- Department of Radiation Oncology, Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN 46202, USA.
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Dynlacht JR, Bittner ME, Bethel JA, Beck BD. The non-homologous end-joining pathway is not involved in the radiosensitization of mammalian cells by heat shock. J Cell Physiol 2003; 196:557-64. [PMID: 12891712 DOI: 10.1002/jcp.10334] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A synergistic increase in cell killing is observed when a heat-shock is administered prior to, during, or immediately after exposure to ionizing radiation (IR). This phenomenon, known as heat-radiosensitization, is believed to be mediated by inhibition of repair of radiation-induced double strand breaks (DSB) when cells are exposed to temperatures above 42 degrees C. However, the mechanism by which heat inhibits DSB repair is unclear. The bulk of radiation-induced DSBs are repaired via the non-homologous end-joining pathway (NHEJ). Several reports indicate that the Ku70 and Ku80 subunits of the mammalian DNA-dependent protein kinase (DNA-PK), a complex involved in NHEJ, appear to be susceptible to a heat-induced loss of DNA-binding activity, with Ku80 representing the heat-sensitive component. Since the heat-induced loss and subsequent recovery of Ku-DNA binding activity correlates well with heat-radiosensitization, a role for Ku80 and NHEJ in heat-radiosensitization has been proposed. However, direct evidence implicating Ku80 (and NHEJ) in heat-radiosensitization has been indeterminate. In this study, we demonstrate that equitoxic heat treatments at 42.5-45.5 degrees C induce a similar amount of aggregation of Ku80 in human U-1 melanoma cells. These data suggest that the time-temperature-dependent relationship between heat lethality and Ku80 aggregation are similar. However, the aggregation/disaggregation of Ku80 and its transient or permanent inactivation is unrelated to heat-radiosensitization. When survival curves were obtained for irradiated or irradiated and heated Ku80(-/-) mouse embryo fibroblasts (MEFs) and compared with survival curves obtained for wild-type (WT) cells, we found that heat-radiosensitization was not reduced in the Ku80(-/-) cells, but actually increased. Thus, our findings indicate that Ku80 is not essential for heat-radiosensitization. Non-involvement of Ku-dependent or Ku-independent NHEJ pathways in heat-radiosensitization was confirmed by comparing clonogenic survival between DNA ligase IV-defective and WT human cells. Our data therefore implicate homologous recombination in inhibition of repair of radiation-induced DSBs and as a target for heat-radiosensitization.
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Affiliation(s)
- Joseph R Dynlacht
- Department of Radiation Oncology, Indiana University School of Medicine, Indianapolis, Indiana 46202, USA.
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