1
|
Verma N, Tiku AB. Role of mTOR pathway in modulation of radiation induced bystander effects. Int J Radiat Biol 2021; 98:173-182. [PMID: 34855567 DOI: 10.1080/09553002.2022.2013567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE Radiation-induced bystander effect (RIBE) is considered as an important consequence of radiation exposure. Based on the type of effect induced, it has important implications in radiation therapy. mTOR pathway, a key regulator of cell survival, plays an important role in radiation-induced damages. However, the role of mTOR signaling in the modulation of RIBE is still unclear. We evaluated the role of mTOR pathway in RIBE and its relationship with the radiation response of target cells. MATERIALS AND METHODS Direct and bystander effects were evaluated by using clonogenic and MTT assay in five different cell lines. Expression of mTOR pathway proteins in directly targeted and bystander cells was studied using western blotting. RESULTS Among five different cell lines naïve HT1080 and A549 cells exhibited proliferative bystander effect induced by conditioned media and irradiated conditioned media, while no effect was observed in other cell lines. Everolimus significantly abolished the proliferative bystander effect induced in naïve cells. CONCLUSIONS These results suggested that the mTOR pathway plays an important role in RIBEs. These effects are cell type-specific and depending on the radiosensitivity of the target cells, therapeutic benefits of radiation may be modulated by treatment with mTOR inhibitors.
Collapse
Affiliation(s)
- Neha Verma
- Radiation and Cancer Therapeutics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| | - Ashu Bhan Tiku
- Radiation and Cancer Therapeutics Lab, School of Life Sciences, Jawaharlal Nehru University, New Delhi, India
| |
Collapse
|
2
|
Kadhim M, Tuncay Cagatay S, Elbakrawy EM. Non-targeted effects of radiation: a personal perspective on the role of exosomes in an evolving paradigm. Int J Radiat Biol 2021; 98:410-420. [PMID: 34662248 DOI: 10.1080/09553002.2021.1980630] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
PURPOSE Radiation-induced non-targeted effects (NTE) have implications in a variety of areas relevant to radiation biology. Here we evaluate the various cargo associated with exosomal signalling and how they work synergistically to initiate and propagate the non-targeted effects including Genomic Instability and Bystander Effects. CONCLUSIONS Extra cellular vesicles, in particular exosomes, have been shown to carry bystander signals. Exosome cargo may contain nucleic acids, both DNA and RNA, as well as proteins, lipids and metabolites. These cargo molecules have all been considered as potential mediators of NTE. A review of current literature shows mounting evidence of a role for ionizing radiation in modulating both the numbers of exosomes released from affected cells as well as the content of their cargo, and that these exosomes can instigate functional changes in recipient cells. However, there are significant gaps in our understanding, particularly regarding modified exosome cargo after radiation exposure and the functional changes induced in recipient cells.
Collapse
Affiliation(s)
- Munira Kadhim
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Seda Tuncay Cagatay
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Eman Mohammed Elbakrawy
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom.,Department of Radiation Physics, National Center for Radiation Research and Technology, Atomic Energy Authority, 3 Ahmed El-Zomor Al Manteqah Ath Thamenah, Nasr City, Cairo 11787, Egypt
| |
Collapse
|
3
|
Apilan AG, Mothersill C. Targeted and Non-Targeted Mechanisms for Killing Hypoxic Tumour Cells-Are There New Avenues for Treatment? Int J Mol Sci 2021; 22:ijms22168651. [PMID: 34445354 PMCID: PMC8395506 DOI: 10.3390/ijms22168651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 08/07/2021] [Accepted: 08/09/2021] [Indexed: 11/25/2022] Open
Abstract
Purpose: A major issue in radiotherapy is the relative resistance of hypoxic cells to radiation. Historic approaches to this problem include the use of oxygen mimetic compounds to sensitize tumour cells, which were unsuccessful. This review looks at modern approaches aimed at increasing the efficacy of targeting and radiosensitizing hypoxic tumour microenvironments relative to normal tissues and asks the question of whether non-targeted effects in radiobiology may provide a new “target”. Novel techniques involve the integration of recent technological advancements such as nanotechnology, cell manipulation, and medical imaging. Particularly, the major areas of research discussed in this review include tumour hypoxia imaging through PET imaging to guide carbogen breathing, gold nanoparticles, macrophage-mediated drug delivery systems used for hypoxia-activate prodrugs, and autophagy inhibitors. Furthermore, this review outlines several features of these methods, including the mechanisms of action to induce radiosensitization, the increased accuracy in targeting hypoxic tumour microenvironments relative to normal tissue, preclinical/clinical trials, and future considerations. Conclusions: This review suggests that the four novel tumour hypoxia therapeutics demonstrate compelling evidence that these techniques can serve as powerful tools to increase targeting efficacy and radiosensitizing hypoxic tumour microenvironments relative to normal tissue. Each technique uses a different way to manipulate the therapeutic ratio, which we have labelled “oxygenate, target, use, and digest”. In addition, by focusing on emerging non-targeted and out-of-field effects, new umbrella targets are identified, which instead of sensitizing hypoxic cells, seek to reduce the radiosensitivity of normal tissues.
Collapse
|
4
|
Ilyas AM, Alam MK, Musah JD, Yang M, Roy VAL, Lam YW, Lau C. CHO cell dysfunction due to radiation-induced bystander signals observed by real-time electrical impedance measurement. Biosens Bioelectron 2021; 181:113142. [PMID: 33752028 DOI: 10.1016/j.bios.2021.113142] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 02/22/2021] [Accepted: 03/01/2021] [Indexed: 11/30/2022]
Abstract
Radiation-induced bystander effects (RIBE) have raised many concerns about radiation safety and protection. In RIBE, unirradiated cells receive signals from irradiated cells and exhibit irradiation effects. Until now, most RIBE studies have been based on morphological and biochemical characterization. However, research on the impact of RIBE on biophysical properties of cells has been lagging. Non-invasive indium tin oxide (ITO)-based impedance systems have been used as bioimpedance sensors for monitoring cell behaviors. This powerful technique has not been applied to RIBE research. In this work, we employed an electrical cell-ITO substrate impedance system (ECIIS) to study the RIBE on Chinese hamster ovary (CHO) cells. The bioimpedance of bystander CHO cells (BCHO), alpha(α)-particle (Am-241) irradiated CHO (ICHO), and untreated/unirradiated CHO (UCHO) cells were monitored with a sampling interval of 8 s over a period of 24 h. Media from ICHO cells exposed to different radiation doses (0.3 nGy, 0.5 nGy, and 0.7 nGy) were used to investigate the radiation dose dependence of BCHO cells' impedance. In parallel, we imaged the cells at times where impedance changes were observed. By analyzing the changes in absolute impedance and cell size/cell number with time, we observed that BCHO cells mimicked ICHO cells in terms of modification in cell morphology and proliferation rate. Furthermore, these effects appeared to be time-dependent and inversely proportional to the radiation dose. Hence, this approach allows a label-free study of cellular responses to RIBE with high sensitivity and temporal resolution and can provide crucial insights into the RIBE mechanism.
Collapse
Affiliation(s)
- A M Ilyas
- Department of Physics, City University of Hong Kong, Kowloon 999077, Hong Kong, China; Department of Physics, Federal University Oye-Ekiti, Ekiti State 3600001, Nigeria.
| | - Md Kowsar Alam
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon 999077, Hong Kong, China; Department of Physics, University of Chittagong, Chittagong 4331, Bangladesh
| | - Jamal-Deen Musah
- Department of Material Science and Engineering, State Key Laboratory of Terahertz and Millimeter Waves, City University of Hong Kong, Kowloon 999077, Hong Kong, China
| | - Mengsu Yang
- Department of Biomedical Sciences, City University of Hong Kong, Kowloon 999077, Hong Kong, China
| | - Vellaisamy A L Roy
- James Watt School of Engineering, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Yun Wah Lam
- Department of Chemistry, City University of Hong Kong, Kowloon 999077, Hong Kong, China
| | - Condon Lau
- Department of Physics, City University of Hong Kong, Kowloon 999077, Hong Kong, China
| |
Collapse
|
5
|
Panzarini E, Vergallo C, Fanizzi FP, Mariano S, Tata AM, Dini L. The dialogue between died and viable cells: in vitro and in vivo bystander effects and 1H-NMR-based metabolic profiling of soluble factors. PURE APPL CHEM 2019. [DOI: 10.1515/pac-2018-1226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
The bystander effect (BE) is an important biological phenomenon that induces damages in distant and not directly affected by a chemical/physical stress cells. This effect, well known in ionizing radiation treatment, relies on reactive signals released by exposed cells and transmitted via cell–cell interaction or culture medium. In this study, cycloheximide (CHX)-induced apoptotic U937 cells and untreated THP-1 cells were chosen to investigate the chemical-induced BE. The effects of apoptotic U937 cells culture medium, Conditioned Medium (CM), on THP-1 cells were evaluated by morphological and immunohistochemical analysis performed by light microscopy; 1D 1H and 2D J-resolved (JRES) NMR metabolomic analysis has been used to characterize the molecules involved in the BE. In summary, this study indicates that: CM of CHX-treated U937 cells induces a time-dependent induction of toxicity, probably apoptotic cell death, and macrophagic differentiation in THP-1 cells; CM contains different metabolites respect fresh culture medium; CM recruits in vivo activated fibroblasts, endothelial cells, macrophages and mononuclear inflammatory cells in rat calf muscles. These data suggest that CHX exposed cells could cause BE through the release, during the apoptotic process, of soluble factors into the medium that could be exploited in anticancer protocols.
Collapse
Affiliation(s)
- Elisa Panzarini
- Department of Biological and Environmental Sciences and Technologies (Di.S.Te.B.A.) , University of Salento , Lecce , Italy
| | - Cristian Vergallo
- Department of Pharmacy , University of Chieti-Pescara “G. D’Annunzio” , Chieti , Italy
| | - Francesco Paolo Fanizzi
- Department of Biological and Environmental Sciences and Technologies (Di.S.Te.B.A.) , University of Salento , Lecce , Italy
| | - Stefania Mariano
- Department of Biological and Environmental Sciences and Technologies (Di.S.Te.B.A.) , University of Salento , Lecce , Italy
| | - Ada Maria Tata
- Department of Biology and Biotechnology “C. Darwin” , Sapienza University of Rome , Rome , Italy
| | - Luciana Dini
- Department of Biology and Biotechnology “C. Darwin” , Sapienza University of Rome , Rome , Italy
- CNR-Nanotec , Lecce , Italy
| |
Collapse
|
6
|
Relevance of Non-Targeted Effects for Radiotherapy and Diagnostic Radiology; A Historical and Conceptual Analysis of Key Players. Cancers (Basel) 2019; 11:cancers11091236. [PMID: 31450803 PMCID: PMC6770832 DOI: 10.3390/cancers11091236] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 08/16/2019] [Accepted: 08/18/2019] [Indexed: 11/17/2022] Open
Abstract
Non-targeted effects (NTE) such as bystander effects or genomic instability have been known for many years but their significance for radiotherapy or medical diagnostic radiology are far from clear. Central to the issue are reported differences in the response of normal and tumour tissues to signals from directly irradiated cells. This review will discuss possible mechanisms and implications of these different responses and will then discuss possible new therapeutic avenues suggested by the analysis. Finally, the importance of NTE for diagnostic radiology and nuclear medicine which stems from the dominance of NTE in the low-dose region of the dose–response curve will be presented. Areas such as second cancer induction and microenvironment plasticity will be discussed.
Collapse
|
7
|
Lad J, Rusin A, Seymour C, Mothersill C. An investigation into neutron-induced bystander effects: How low can you go? ENVIRONMENTAL RESEARCH 2019; 175:84-99. [PMID: 31108356 DOI: 10.1016/j.envres.2019.04.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2019] [Revised: 04/28/2019] [Accepted: 04/29/2019] [Indexed: 06/09/2023]
Abstract
Neutron radiation is very harmful to both individual organisms and the environment. A n understanding of all aspects of both direct and indirect effects of radiation is necessary to accurately assess the risk of neutron radiation exposure. This review seeks to review current evidence in the literature for radiation-induced bystander effects and related effects attributable to neutron radiation. It also attempts to determine if the suggested evidence in the literature is sufficient to justify claims that neutron-based radiation can cause radiation-induced bystander effects. Lastly, the present paper suggests potential directions for future research concerning neutron radiation-induced bystander effects. Data was collected from studies investigating radiation-induced bystander effects and was used to mathematically generate pooled datasets and putative trends; this was done to potentially elucidate both the appearance of a conventional trend for radiation-induced bystander effects in studies using different types of radiation. Furthermore, literature review was used to compare studies utilizing similar tissue models to determine if neutron effects follow similar trends as those produced by electromagnetic radiation. We conclude that the current understanding of neutron-attributable radiation-induced bystander effects is incomplete. Various factors such as high gamma contamination during the irradiations, unestablished thresholds for gamma effects, different cell lines, energies, and different dose rates affected our ability to confirm a relationship between neutron irradiation and RIBE, particularly in low-dose regions below 100 mGy. It was determined through meta-analysis of the data that effects attributable to neutrons do seem to exist at higher doses, while gamma effects seem likely predominant at lower dose regions. Therefore, whether neutrons can induce bystander effects at lower doses remains unclear. Further research is required to confirm these findings and various recommendations are made to assist in this effort. With these recommendations, we hope that research conducted in the future will be better equipped to explore the indirect effects of neutron radiation as they pertain to biological and ecological phenomena.
Collapse
Affiliation(s)
- Jigar Lad
- Department of Physics and Astronomy, McMaster University, Hamilton, Canada.
| | - Andrej Rusin
- Department of Biology, McMaster University, Hamilton, Canada
| | - Colin Seymour
- Department of Biology, McMaster University, Hamilton, Canada
| | | |
Collapse
|
8
|
Rusin A, Lapied E, Le M, Seymour C, Oughton D, Haanes H, Mothersill C. Effect of gamma radiation on the production of bystander signals from three earthworm species irradiated in vivo. ENVIRONMENTAL RESEARCH 2019; 168:211-221. [PMID: 30317106 DOI: 10.1016/j.envres.2018.09.023] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Revised: 09/03/2018] [Accepted: 09/19/2018] [Indexed: 06/08/2023]
Abstract
The effect of gamma radiation delivered over 24 h on the induction of bystander signals of three earthworm species exposed in vivo was investigated: A. chlorotica, A. caliginosa, and E. tetraedra. Worms were exposed to external gamma irradiation (Co-60 source) for 24 h and samples of head, body, and clitellum were dissected from exposed and control worms and placed in culture medium for 24 h at 19 C. The harvested medium was filtered and assayed for expression of bystander signals using both clonogenic and mitochondrial reporter assays. Different responses were observed in the different species and in the different tissues. A. chlorotica worm-treated reporters show insignificant mitochondrial response for all sections, yet a significant clonogenic reduction in survival for body sections. A. caliginosa worm-treated reporters show a significant mitochondrial response for some sections and insignificant mitochondrial response and insignificant reduction in clonogenic survival for the rest. E. tetraedra worms from a control site show significant evidence of bystander signalling, measured by mitochondrial response in reporter cells, for all sections while those harvested from a contaminated site show insignificant changes in baseline signalling when exposed to the challenge dose. In vivo exposure of earthworm species shows evidence of bystander signalling using two different reporter assays. This effect varied between the different species and tissues. There is also evidence of attenuated bystander signalling in worms harvested from a site contaminated with radiation.
Collapse
Affiliation(s)
- Andrej Rusin
- Dept. of Biology, McMaster University, Hamilton, ON, Canada.
| | - Emmanuel Lapied
- Centre for Environmental Radioactivity (CERAD), Norwegian University of Life Sciences, PO Box 5003, 1430 Aas, Norway
| | - Michelle Le
- Dept. of Biology, McMaster University, Hamilton, ON, Canada
| | - Colin Seymour
- Dept. of Biology, McMaster University, Hamilton, ON, Canada
| | - Deborah Oughton
- Centre for Environmental Radioactivity (CERAD), Norwegian University of Life Sciences, PO Box 5003, 1430 Aas, Norway
| | - Hallvard Haanes
- Centre for Environmental Radioactivity (CERAD), Norwegian University of Life Sciences, PO Box 5003, 1430 Aas, Norway; Norwegian Radiation Protection Authority (NRPA), Østerås, Norway
| | | |
Collapse
|
9
|
Mothersill C, Rusin A, Fernandez-Palomo C, Seymour C. History of bystander effects research 1905-present; what is in a name? Int J Radiat Biol 2017; 94:696-707. [DOI: 10.1080/09553002.2017.1398436] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
| | - Andrej Rusin
- Department of Biology, McMaster University, Hamilton, Canada
| | | | - Colin Seymour
- Department of Biology, McMaster University, Hamilton, Canada
| |
Collapse
|
10
|
Lee MH, Lee KM, Kim EH. Neighbor effect: penumbra-dose exposed neighbor cells contribute to the enhanced survival of high-dose targeted cells. Int J Radiat Biol 2017; 93:1227-1238. [PMID: 28738724 DOI: 10.1080/09553002.2017.1359430] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
PURPOSE In the last decade, new types of 'bystander effect' have been suggested by multiple research groups and have been challenged by others. In this study, we explored a new type of bystander effect, which has been defined in previous studies as the enhancement of the survival of high-dose targeted cells due to the penumbra-dose exposed neighbor cells. Intensity-modulated radiation therapy, which is the most widely used treatment modality, generates local regions of gradient doses between targeted and shielded cells throughout the treatment volume; therefore, we were urged to ascertain whether the new type of effect is real and to suggest a revised treatment planning. MATERIALS AND METHODS Cellular responses under non-uniform beam fields were observed in rat gliosarcoma cells, rat diencephalon cells, and mouse endothelial cells. The cells were irradiated with 200 kVp X-rays in two types: (1) all the cells in the flask were exposed to the X-ray beam (whole-beam exposure) and (2) half of the cells in the flask were exposed to the beam while the other half, or neighbor cells, were shielded from the beam (half-beam exposure). Target cells were exposed to 1, 2, 4, 6, 8, and 10 Gy, and the penumbra dose was approximately 10%-20% of the target dose. RESULTS Target cells survived high-dose (> 6 Gy) radiation exposures better under half-beam exposure with the low penumbra-dose exposed neighbor cells around than under whole-beam exposure. The survival of the targeted cells from half-beam exposure was reduced when the radiation self-conditioned medium was replaced with a fresh one immediately after irradiation. Survival was further reduced when the targeted cells were harvested immediately after irradiation and incubated in new dishes with fresh culture media until the colony was counted. CONCLUSION We have collected data of good statistics by several post-irradiation treatments of targeted cells to ascertain that the new type of bystander effect is real. The low penumbra-dose exposed neighbor cells benefited the survival of the high-dose targeted cells.
Collapse
Affiliation(s)
- Min-Ho Lee
- a Department of Nuclear Engineering, Radiation Bioengineering Laboratory , Seoul National University , Seoul , Republic of Korea
| | - Ki-Man Lee
- a Department of Nuclear Engineering, Radiation Bioengineering Laboratory , Seoul National University , Seoul , Republic of Korea
| | - Eun-Hee Kim
- a Department of Nuclear Engineering, Radiation Bioengineering Laboratory , Seoul National University , Seoul , Republic of Korea
| |
Collapse
|
11
|
Significance and nature of bystander responses induced by various agents. MUTATION RESEARCH-REVIEWS IN MUTATION RESEARCH 2017; 773:104-121. [DOI: 10.1016/j.mrrev.2017.05.003] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Accepted: 05/05/2017] [Indexed: 02/07/2023]
|
12
|
Low Concentration of Exogenous Carbon Monoxide Modulates Radiation-Induced Bystander Effect in Mammalian Cell Cluster Model. Int J Mol Sci 2016; 17:ijms17122051. [PMID: 27941646 PMCID: PMC5187851 DOI: 10.3390/ijms17122051] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Revised: 11/24/2016] [Accepted: 12/01/2016] [Indexed: 01/18/2023] Open
Abstract
During radiotherapy procedures, radiation-induced bystander effect (RIBE) can potentially lead to genetic hazards to normal tissues surrounding the targeted regions. Previous studies showed that RIBE intensities in cell cluster models were much higher than those in monolayer cultured cell models. On the other hand, low-concentration carbon monoxide (CO) was previously shown to exert biological functions via binding to the heme domain of proteins and then modulating various signaling pathways. In relation, our previous studies showed that exogenous CO generated by the CO releasing molecule, tricarbonyldichlororuthenium (CORM-2), at a relatively low concentration (20 µM), effectively attenuated the formation of RIBE-induced DNA double-strand breaks (DSB) and micronucleus (MN). In the present work, we further investigated the capability of a low concentration of exogenous CO (CORM-2) of attenuating or inhibiting RIBE in a mixed-cell cluster model. Our results showed that CO (CORM-2) with a low concentration of 30 µM could effectively suppress RIBE-induced DSB (p53 binding protein 1, p53BP1), MN formation and cell proliferation in bystander cells but not irradiated cells via modulating the inducible nitric oxide synthase (iNOS) andcyclooxygenase-2 (COX-2). The results can help mitigate RIBE-induced hazards during radiotherapy procedures.
Collapse
|
13
|
Abstract
The World Health Organization lists a constellation of 17 tropical diseases that afflict approximately one in six individuals on the planet and, until recently, few resources have been devoted to the treatment and eradication of those diseases. They are often referred to as the diseases of the “bottom billion,” because they are most prevalent among the poorest individuals in impoverished tropical nations. However, the few studies that have been performed reveal an extraordinary world of molecular and cellular adaptations that facilitate the pathogens’ survival in hosts ranging from insects to humans. A compelling case can be made that even a modest investment toward understanding the basic molecular and cell biology of these neglected pathogens has a high probability of yielding exciting new cellular mechanisms and insights into novel ways of combating these diseases.
Collapse
Affiliation(s)
- William Sullivan
- Department of Molecular, Cell and Developmental Biology, University of California, Santa Cruz, Santa Cruz, CA 95064
| |
Collapse
|
14
|
Burtt JJ, Thompson PA, Lafrenie RM. Non-targeted effects and radiation-induced carcinogenesis: a review. JOURNAL OF RADIOLOGICAL PROTECTION : OFFICIAL JOURNAL OF THE SOCIETY FOR RADIOLOGICAL PROTECTION 2016; 36:R23-R35. [PMID: 26910391 DOI: 10.1088/0952-4746/36/1/r23] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Exposure to ionising radiation is clearly associated with an increased risk of developing some types of cancer. However, the contribution of non-targeted effects to cancer development after exposure to ionising radiation is far less clear. The currently used cancer risk model by the international radiation protection community states that any increase in radiation exposure proportionately increases the risk of developing cancer. However, this stochastic cancer risk model does not take into account any contribution from non-targeted effects. Nor does it consider the possibility of a bystander mechanism in the induction of genomic instability. This paper reviews the available evidence to date for a possible role for non-targeted effects to contribute to cancer development after exposure to ionising radiation. An evolution in the understanding of the mechanisms driving non-targeted effects after exposure to ionising radiation is critical to determine the true contribution of non-targeted effects on the risk of developing cancer. Such an evolution will likely only be achievable through coordinated multidisciplinary teams combining several fields of study including: genomics, proteomics, cell biology, molecular epidemiology, and traditional epidemiology.
Collapse
Affiliation(s)
- Julie J Burtt
- Canadian Nuclear Safety Commission, 280 Slater Street, Ottawa, Ontario, K1P 5S9, Canada
| | | | | |
Collapse
|
15
|
Particle Radiation-Induced Nontargeted Effects in Bone-Marrow-Derived Endothelial Progenitor Cells. Stem Cells Int 2015; 2015:496512. [PMID: 26074973 PMCID: PMC4436457 DOI: 10.1155/2015/496512] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Revised: 02/23/2015] [Accepted: 02/24/2015] [Indexed: 01/17/2023] Open
Abstract
Bone-marrow- (BM-) derived endothelial progenitor cells (EPCs) are critical for endothelial cell maintenance and repair. During future space exploration missions astronauts will be exposed to space irradiation (IR) composed of a spectrum of low-fluence protons ((1)H) and high charge and energy (HZE) nuclei (e.g., iron-(56)Fe) for extended time. How the space-type IR affects BM-EPCs is limited. In media transfer experiments in vitro we studied nontargeted effects induced by (1)H- and (56)Fe-IR conditioned medium (CM), which showed significant increase in the number of p-H2AX foci in nonirradiated EPCs between 2 and 24 h. A 2-15-fold increase in the levels of various cytokines and chemokines was observed in both types of IR-CM at 24 h. Ex vivo analysis of BM-EPCs from single, low-dose, full-body (1)H- and (56)Fe-IR mice demonstrated a cyclical (early 5-24 h and delayed 28 days) increase in apoptosis. This early increase in BM-EPC apoptosis may be the effect of direct IR exposure, whereas late increase in apoptosis could be a result of nontargeted effects (NTE) in the cells that were not traversed by IR directly. Identifying the role of specific cytokines responsible for IR-induced NTE and inhibiting such NTE may prevent long-term and cyclical loss of stem and progenitors cells in the BM milieu.
Collapse
|
16
|
Edin NJ, Altaner Č, Altanerova V, Ebbesen P. TGF-B3 Dependent Modification of Radiosensitivity in Reporter Cells Exposed to Serum From Whole-Body Low Dose-Rate Irradiated Mice. Dose Response 2015; 13:10.2203_dose-response.14-015.Edin. [PMID: 26673923 PMCID: PMC4674161 DOI: 10.2203/dose-response.14-015.edin] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Prior findings in vitro of a TGF-β3 dependent mechanism induced by low dose-rate irradiation and resulting in increased radioresistance and removal of low dose hyper-radiosensitivity (HRS) was tested in an in vivo model. DBA/2 mice were given whole-body irradiation for 1 h at low dose-rates (LDR) of 0.3 or 0.03 Gy/h. Serum was harvested and added to RPMI (4% mouse serum and 6% bovine serum).This medium was transferred to reporter cells (T-47D breast cancer cells or T98G glioblastoma cells). The response to subsequent challenge irradiation of the reporter cells was measured by the colony assay. While serum from unirradiated control mice had no effect on the radiosensitivity in the reporter cells, serum from mice given 0.3 Gy/h or 0.03 Gy/h for 1 h removed HRS and also increased survival in response to doses up to 5 Gy. The effect lasted for at least 15 months after irradiation. TGF-β3 neutralizer added to the medium containing mouse serum inhibited the effect. Serum from mice given irradiation of 0.3 Gy/h for 1 h and subsequently treated with iNOS inhibitor 1400W did not affect radiosensitivity in reporter cells; neither did serum from the unirradiated progeny of mice given 1h LDR whole-body irradiation.
Collapse
Affiliation(s)
- Nina Jeppesen Edin
- Department of Physics, University of Oslo, 0316 Oslo, Norway ; Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, Montebello, 0310 Oslo, Norway
| | - Čestmír Altaner
- Cancer Research Institute, Slovak Academy of Sciences, Bratislava, Slovakia
| | | | - Peter Ebbesen
- Department of Physics, University of Oslo, 0316 Oslo, Norway ; Laboratory for Stem Cell Research, Aalborg University, Fredrik Bajers Vej 3B, 9220 Aalborg Ø. Denmark
| |
Collapse
|
17
|
Fernandez-Palomo C, Bräuer-Krisch E, Laissue J, Vukmirovic D, Blattmann H, Seymour C, Schültke E, Mothersill C. Use of synchrotron medical microbeam irradiation to investigate radiation-induced bystander and abscopal effects in vivo. Phys Med 2015; 31:584-95. [PMID: 25817634 DOI: 10.1016/j.ejmp.2015.03.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2014] [Revised: 03/06/2015] [Accepted: 03/09/2015] [Indexed: 01/01/2023] Open
Abstract
The question of whether bystander and abscopal effects are the same is unclear. Our experimental system enables us to address this question by allowing irradiated organisms to partner with unexposed individuals. Organs from both animals and appropriate sham and scatter dose controls are tested for expression of several endpoints such as calcium flux, role of 5HT, reporter assay cell death and proteomic profile. The results show that membrane related functions of calcium and 5HT are critical for true bystander effect expression. Our original inter-animal experiments used fish species whole body irradiated with low doses of X-rays, which prevented us from addressing the abscopal effect question. Data which are much more relevant in radiotherapy are now available for rats which received high dose local irradiation to the implanted right brain glioma. The data were generated using quasi-parallel microbeams at the biomedical beamline at the European Synchrotron Radiation Facility in Grenoble France. This means we can directly compare abscopal and "true" bystander effects in a rodent tumour model. Analysis of right brain hemisphere, left brain and urinary bladder in the directly irradiated animals and their unirradiated partners strongly suggests that bystander effects (in partner animals) are not the same as abscopal effects (in the irradiated animal). Furthermore, the presence of a tumour in the right brain alters the magnitude of both abscopal and bystander effects in the tissues from the directly irradiated animal and in the unirradiated partners which did not contain tumours, meaning the type of signal was different.
Collapse
Affiliation(s)
- Cristian Fernandez-Palomo
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada.
| | - Elke Bräuer-Krisch
- European Synchrotron Radiation Facility, BP 220 6, rue Jules Horowitz, 38043 Grenoble, France
| | - Jean Laissue
- University of Bern, Hochschulstrasse 4, CH-3012 Bern, Switzerland
| | - Dusan Vukmirovic
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | | | - Colin Seymour
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| | - Elisabeth Schültke
- Department of Radiotherapy, Rostock University Medical Center, Südring 75, 18059 Rostock, Germany
| | - Carmel Mothersill
- Department of Medical Physics and Applied Radiation Sciences, McMaster University, Hamilton, Ontario L8S 4K1, Canada
| |
Collapse
|
18
|
Baskar R, Dai J, Wenlong N, Yeo R, Yeoh KW. Biological response of cancer cells to radiation treatment. Front Mol Biosci 2014; 1:24. [PMID: 25988165 PMCID: PMC4429645 DOI: 10.3389/fmolb.2014.00024] [Citation(s) in RCA: 323] [Impact Index Per Article: 32.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2014] [Accepted: 10/31/2014] [Indexed: 12/15/2022] Open
Abstract
Cancer is a class of diseases characterized by uncontrolled cell growth and has the ability to spread or metastasize throughout the body. In recent years, remarkable progress has been made toward the understanding of proposed hallmarks of cancer development, care, and treatment modalities. Radiation therapy or radiotherapy is an important and integral component of cancer management, mostly conferring a survival benefit. Radiation therapy destroys cancer by depositing high-energy radiation on the cancer tissues. Over the years, radiation therapy has been driven by constant technological advances and approximately 50% of all patients with localized malignant tumors are treated with radiation at some point in the course of their disease. In radiation oncology, research and development in the last three decades has led to considerable improvement in our understanding of the differential responses of normal and cancer cells. The biological effectiveness of radiation depends on the linear energy transfer (LET), total dose, number of fractions and radiosensitivity of the targeted cells or tissues. Radiation can either directly or indirectly (by producing free radicals) damages the genome of the cell. This has been challenged in recent years by a newly identified phenomenon known as radiation induced bystander effect (RIBE). In RIBE, the non-irradiated cells adjacent to or located far from the irradiated cells/tissues demonstrate similar responses to that of the directly irradiated cells. Understanding the cancer cell responses during the fractions or after the course of irradiation will lead to improvements in therapeutic efficacy and potentially, benefitting a significant proportion of cancer patients. In this review, the clinical implications of radiation induced direct and bystander effects on the cancer cell are discussed.
Collapse
Affiliation(s)
- Rajamanickam Baskar
- Division of Cellular and Molecular Research, Department of Radiation Oncology, National Cancer Centre Singapore, Singapore
| | - Jiawen Dai
- Division of Cellular and Molecular Research, Department of Radiation Oncology, National Cancer Centre Singapore, Singapore
| | - Nei Wenlong
- Division of Cellular and Molecular Research, Department of Radiation Oncology, National Cancer Centre Singapore, Singapore
| | - Richard Yeo
- Division of Cellular and Molecular Research, Department of Radiation Oncology, National Cancer Centre Singapore, Singapore
| | - Kheng-Wei Yeoh
- Division of Cellular and Molecular Research, Department of Radiation Oncology, National Cancer Centre Singapore, Singapore
| |
Collapse
|
19
|
Radiobiological effects of multiple vs. single low-dose pre-irradiation on the HT29 cell line. Contemp Oncol (Pozn) 2014; 18:230-3. [PMID: 25258579 PMCID: PMC4171467 DOI: 10.5114/wo.2014.41386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 12/18/2013] [Accepted: 02/25/2014] [Indexed: 11/17/2022] Open
Abstract
AIM OF THE STUDY Aim of the study was to compare radiobiological effects of multiple vs. single low-dose pre-irradiation on the HT29 cell line. This regime is designed to be as similar as possible to fractionated tumour radiotherapy treatment, and to provide data on radiobiological effects on human tumour cells. MATERIAL AND METHODS The cell line used in the study was HT29 (human colorectal adenocarcinoma, American Type Culture Collection HTB-38™). Also, for comparison, the MRC5 cell line (human foetal lung fibroblasts, American Type Culture Collection CCL 171) was used. Four-day treatment in a 4 × 2 Gy regime was performed. Cell viability was evaluated by tetrazolium colorimetric MTT assay. RESULTS Multiple low-dose pre-irradiation induced a stronger radioadaptive response compared to single low-dose application in the HT29 cell line. Multiple pre-irradiation with 0.03 Gy and 0.05 Gy caused radioadaptive effects, while in both single and multiple low-dose pre-irradiation regimes 0.07 Gy led to radiosensitivity. Radiobiological effects induced in the HT29 cell line by low-dose pre-irradiation were evidently weak during the treatment time, because a single low-dose applied only on the first day gave no radioadaptive effects. In the MRC5 cell line different effects were registered, since radioadaptive response has not been observed after multiple or single pre-irradiation. CONCLUSIONS The obtained data are interesting, especially for the possible application of low-dose pre-irradiation in radiotherapy.
Collapse
|
20
|
Sasi SP, Song J, Park D, Enderling H, McDonald JT, Gee H, Garrity B, Shtifman A, Yan X, Walsh K, Natarajan M, Kishore R, Goukassian DA. TNF-TNFR2/p75 signaling inhibits early and increases delayed nontargeted effects in bone marrow-derived endothelial progenitor cells. J Biol Chem 2014; 289:14178-93. [PMID: 24711449 DOI: 10.1074/jbc.m114.567743] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
TNF-α, a pro-inflammatory cytokine, is highly expressed after being irradiated (IR) and is implicated in mediating radiobiological bystander responses (RBRs). Little is known about specific TNF receptors in regulating TNF-induced RBR in bone marrow-derived endothelial progenitor cells (BM-EPCs). Full body γ-IR WT BM-EPCs showed a biphasic response: slow decay of p-H2AX foci during the initial 24 h and increase between 24 h and 7 days post-IR, indicating a significant RBR in BM-EPCs in vivo. Individual TNF receptor (TNFR) signaling in RBR was evaluated in BM-EPCs from WT, TNFR1/p55KO, and TNFR2/p75KO mice, in vitro. Compared with WT, early RBR (1-5 h) were inhibited in p55KO and p75KO EPCs, whereas delayed RBR (3-5 days) were amplified in p55KO EPCs, suggesting a possible role for TNFR2/p75 signaling in delayed RBR. Neutralizing TNF in γ-IR conditioned media (CM) of WT and p55KO BM-EPCs largely abolished RBR in both cell types. ELISA protein profiling of WT and p55KO EPC γ-IR-CM over 5 days showed significant increases in several pro-inflammatory cytokines, including TNF-α, IL-1α (Interleukin-1 alpha), RANTES (regulated on activation, normal T cell expressed and secreted), and MCP-1. In vitro treatments with murine recombinant (rm) TNF-α and rmIL-1α, but not rmMCP-1 or rmRANTES, increased the formation of p-H2AX foci in nonirradiated p55KO EPCs. We conclude that TNF-TNFR2 signaling may induce RBR in naïve BM-EPCs and that blocking TNF-TNFR2 signaling may prevent delayed RBR in BM-EPCs, conceivably, in bone marrow milieu in general.
Collapse
Affiliation(s)
- Sharath P Sasi
- From the Cardiovascular Research Center, Steward Research and Specialty Projects Corporation, Brighton, Massachusetts 02135
| | - Jin Song
- From the Cardiovascular Research Center, Steward Research and Specialty Projects Corporation, Brighton, Massachusetts 02135
| | - Daniel Park
- From the Cardiovascular Research Center, Steward Research and Specialty Projects Corporation, Brighton, Massachusetts 02135
| | - Heiko Enderling
- the Center of Cancer Systems Biology, GeneSys Research Institute, Boston, Massachusetts 02135, Department of Integrated Mathematical Oncology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida 33612, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - J Tyson McDonald
- the Center of Cancer Systems Biology, GeneSys Research Institute, Boston, Massachusetts 02135, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Hannah Gee
- From the Cardiovascular Research Center, Steward Research and Specialty Projects Corporation, Brighton, Massachusetts 02135
| | - Brittany Garrity
- From the Cardiovascular Research Center, Steward Research and Specialty Projects Corporation, Brighton, Massachusetts 02135
| | - Alexander Shtifman
- From the Cardiovascular Research Center, Steward Research and Specialty Projects Corporation, Brighton, Massachusetts 02135, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Xinhua Yan
- From the Cardiovascular Research Center, Steward Research and Specialty Projects Corporation, Brighton, Massachusetts 02135, the Center of Cancer Systems Biology, GeneSys Research Institute, Boston, Massachusetts 02135, Tufts University School of Medicine, Boston, Massachusetts 02111
| | - Kenneth Walsh
- the Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts 02118
| | - Mohan Natarajan
- the University of Texas Health Science Center, San Antonio, Texas 78229, and
| | - Raj Kishore
- the Feinberg Cardiovascular Research Institute, Northwestern University, Chicago, Illinois 60611
| | - David A Goukassian
- From the Cardiovascular Research Center, Steward Research and Specialty Projects Corporation, Brighton, Massachusetts 02135, Tufts University School of Medicine, Boston, Massachusetts 02111, the Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, Massachusetts 02118,
| |
Collapse
|
21
|
Pereira S, Malard V, Ravanat JL, Davin AH, Armengaud J, Foray N, Adam-Guillermin C. Low doses of gamma-irradiation induce an early bystander effect in zebrafish cells which is sufficient to radioprotect cells. PLoS One 2014; 9:e92974. [PMID: 24667817 PMCID: PMC3965492 DOI: 10.1371/journal.pone.0092974] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2013] [Accepted: 02/27/2014] [Indexed: 11/18/2022] Open
Abstract
The term “bystander effect” is used to describe an effect in which cells that have not been exposed to radiation are affected by irradiated cells though various intracellular signaling mechanisms. In this study we analyzed the kinetics and mechanisms of bystander effect and radioadaptation in embryonic zebrafish cells (ZF4) exposed to chronic low dose of gamma rays. ZF4 cells were irradiated for 4 hours with total doses of gamma irradiation ranging from 0.01–0.1 Gy. In two experimental conditions, the transfer of irradiated cells or culture medium from irradiated cells results in the occurrence of DNA double strand breaks in non-irradiated cells (assessed by the number of γ-H2AX foci) that are repaired at 24 hours post-irradiation whatever the dose. At low total irradiation doses the bystander effect observed does not affect DNA repair mechanisms in targeted and bystander cells. An increase in global methylation of ZF4 cells was observed in irradiated cells and bystander cells compared to control cells. We observed that pre-irradiated cells which are then irradiated for a second time with the same doses contained significantly less γ-H2AX foci than in 24 h gamma-irradiated control cells. We also showed that bystander cells that have been in contact with the pre-irradiated cells and then irradiated alone present less γ-H2AX foci compared to the control cells. This radioadaptation effect is significantly more pronounced at the highest doses. To determine the factors involved in the early events of the bystander effect, we performed an extensive comparative proteomic study of the ZF4 secretomes upon irradiation. In the experimental conditions assayed here, we showed that the early events of bystander effect are probably not due to the secretion of specific proteins neither the oxidation of these secreted proteins. These results suggest that early bystander effect may be due probably to a combination of multiple factors.
Collapse
Affiliation(s)
- Sandrine Pereira
- Institut de Radioprotection et de Sûreté Nucléaire, PRP-Environnement/SERIS, Laboratoire d’Ecotoxicologie des Radionucléides, Cadarache, St Paul Lez Durance, France
- CRCL - UMR INSERM 1052 - CNRS 5286, Equipe de Radiobiologie, Cheney A- 1éme étage, Lyon, France
- * E-mail:
| | - Véronique Malard
- CEA, DSV, IBEB, Lab Biochim System Perturb, Bagnols-sur-Cèze, France
| | - Jean-Luc Ravanat
- Laboratoire des Lésions des Acides Nucléiques, INAC/Scib UMR E3 CEA-UJF, CEA Grenoble, Grenoble, France
| | - Anne-Hélène Davin
- CEA, DSV, IBEB, Lab Biochim System Perturb, Bagnols-sur-Cèze, France
| | - Jean Armengaud
- CEA, DSV, IBEB, Lab Biochim System Perturb, Bagnols-sur-Cèze, France
| | - Nicolas Foray
- CRCL - UMR INSERM 1052 - CNRS 5286, Equipe de Radiobiologie, Cheney A- 1éme étage, Lyon, France
| | - Christelle Adam-Guillermin
- Institut de Radioprotection et de Sûreté Nucléaire, PRP-Environnement/SERIS, Laboratoire d’Ecotoxicologie des Radionucléides, Cadarache, St Paul Lez Durance, France
| |
Collapse
|
22
|
Non-targeted radiation effects in vivo: a critical glance of the future in radiobiology. Cancer Lett 2013; 356:34-42. [PMID: 24333869 DOI: 10.1016/j.canlet.2013.11.018] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2013] [Revised: 11/18/2013] [Accepted: 11/21/2013] [Indexed: 11/22/2022]
Abstract
Radiation-induced bystander effects (RIBE), demonstrate the induction of biological non-targeted effects in cells which have not directly hit by radiation or by free radicals produced by ionization events. Although RIBE have been demonstrated using a variety of biological endpoints the mechanism(s) of this phenomenon still remain unclear. The controversial results of the in vitro RIBE and the evidence of non-targeted effects in various in vivo systems are discussed. The experimental evidence on RIBE, indicate that a more analytical and mechanistic in depth approach is needed to secure an answer to one of the most intriguing questions in radiobiology.
Collapse
|
23
|
Edin NJ, Sandvik JA, Vollan HS, Reger K, Görlach A, Pettersen EO. The role of nitric oxide radicals in removal of hyper-radiosensitivity by priming irradiation. JOURNAL OF RADIATION RESEARCH 2013; 54:1015-28. [PMID: 23685670 PMCID: PMC3823782 DOI: 10.1093/jrr/rrt061] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
In this study, a mechanism in which low-dose hyper-radiosensitivity (HRS) is permanently removed, induced by low-dose-rate (LDR) (0.2-0.3 Gy/h for 1 h) but not by high-dose-rate priming (0.3 Gy at 40 Gy/h) was investigated. One HRS-negative cell line (NHIK 3025) and two HRS-positive cell lines (T-47D, T98G) were used. The effects of different pretreatments on HRS were investigated using the colony assay. Cell-based ELISA was used to measure nitric oxide synthase (NOS) levels, and microarray analysis to compare gene expression in primed and unprimed cells. The data show how permanent removal of HRS, previously found to be induced by LDR priming irradiation, can also be induced by addition of nitric oxide (NO)-donor DEANO combined with either high-dose-rate priming or exposure to prolonged cycling hypoxia followed by reoxygenation, a treatment not involving radiation. The removal of HRS appears not to involve DNA damage induced during priming irradiation as it was also induced by LDR irradiation of cell-conditioned medium without cells present. The permanent removal of HRS in LDR-primed cells was reversed by treatment with inducible nitric oxide synthase (iNOS) inhibitor 1400W. Furthermore, 1400W could also induce HRS in an HRS-negative cell line. The data suggest that LDR irradiation for 1 h, but not 15 min, activates iNOS, and also that sustained iNOS activation is necessary for the permanent removal of HRS by LDR priming. The data indicate that nitric oxide production is involved in the regulatory processes determining cellular responses to low-dose-rate irradiation.
Collapse
Affiliation(s)
- Nina Jeppesen Edin
- Department of Physics, University of Oslo, 0316 Oslo, Norway
- Department of Radiation Biology, Institute for Cancer Research, University Hospital, University of Oslo, 0310 Oslo, Norway
- Corresponding author. Department of Physics, Biophysics Group, PB 1048 Blindern, N-0316 Oslo, Norway. Tel: +47-22-85-54-92; Fax: +47-228-556-71;
| | | | - Hilde Synnøve Vollan
- Department of Clinical Molecular Biology (EpiGen), Institute of Clinical Medicine, Akershus University Hospital, University of Oslo, 1478 Lørenskog, Norway
| | - Katharina Reger
- Experimental and Molecular Pediatric Cardiology, Department of Pediatric Cardiology and Congenital Heart Disease, German Heart Center Munich, Lazarettstr. 36, 80636 Munich, Germany
| | - Agnes Görlach
- Experimental and Molecular Pediatric Cardiology, Department of Pediatric Cardiology and Congenital Heart Disease, German Heart Center Munich, Lazarettstr. 36, 80636 Munich, Germany
| | | |
Collapse
|
24
|
Irons SL, Serra V, Bowler D, Chapman K, Militi S, Lyng F, Kadhim M. The effect of genetic background and dose on non-targeted effects of radiation. Int J Radiat Biol 2012; 88:735-42. [DOI: 10.3109/09553002.2012.715793] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
|
25
|
Asur RS, Sharma S, Chang CW, Penagaricano J, Kommuru IM, Moros EG, Corry PM, Griffin RJ. Spatially fractionated radiation induces cytotoxicity and changes in gene expression in bystander and radiation adjacent murine carcinoma cells. Radiat Res 2012; 177:751-65. [PMID: 22559204 DOI: 10.1667/rr2780.1] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Radiation-induced bystander effects have been extensively studied at low doses, since evidence of bystander induced cell killing and other effects on unirradiated cells were found to be predominant at doses up to 0.5 Gy. Therefore, few studies have examined bystander effects induced by exposure to higher doses of radiation, such as spatially fractionated radiation (GRID) treatment. In the present study, we evaluate the ability of GRID treatment to induce changes in GRID adjacent (bystander) regions, in two different murine carcinoma cell lines following exposure to a single irradiation dose of 10 Gy. Murine SCK mammary carcinoma cells and SCCVII squamous carcinoma cells were irradiated using a brass collimator to create a GRID pattern of nine circular fields 12 mm in diameter with a center-to-center distance of 18 mm. Similar to the typical clinical implementation of GRID, this is approximately a 50:50 ratio of direct and bystander exposure. We also performed experiments by irradiating separate cultures and transferring the medium to unirradiated bystander cultures. Clonogenic survival was evaluated in both cell lines to determine the occurrence of radiation-induced bystander effects. For the purpose of our study, we have defined bystander cells as GRID adjacent cells that received approximately 1 Gy scatter dose or unirradiated cells receiving conditioned medium from irradiated cells. We observed significant bystander killing of cells adjacent to the GRID irradiated regions compared to sham treated controls. We also observed bystander killing of SCK and SCCVII cells cultured in conditioned medium obtained from cells irradiated with 10 Gy. Therefore, our results confirm the occurrence of bystander effects following exposure to a high-dose of radiation and suggest that cell-to-cell contact is not required for these effects. In addition, the gene expression profile for DNA damage and cellular stress response signaling in SCCVII cells after GRID exposure was studied. The occurrence of GRID-induced bystander gene expression changes in significant numbers of DNA damage and cellular stress response signaling genes, providing molecular evidence for possible mechanisms of bystander cell killing.
Collapse
Affiliation(s)
- Rajalakshmi S Asur
- Department of Radiation Oncology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
| | | | | | | | | | | | | | | |
Collapse
|
26
|
MotherSill C, Seymour C. Changing paradigms in radiobiology. Mutat Res 2012; 750:85-95. [PMID: 22273762 DOI: 10.1016/j.mrrev.2011.12.007] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2011] [Accepted: 12/20/2011] [Indexed: 12/21/2022]
Abstract
The last 25 years have seen a major shift in emphasis in the field of radiobiology from a DNA-centric view of how radiation damage occurs to a much more biological view that appreciates the importance of macro-and micro-environments, hierarchical organization, underlying genetics, evolution, adaptation and signaling at all levels from atoms to ecosystems. The new view incorporates concepts of hormesis, nonlinear systems, bioenergy field theory, uncertainty and homeodynamics. While the mechanisms underlying these effects and responses are still far from clear, it is very apparent that their implications are much wider than the field of radiobiology. This reflection discusses the changing views and considers how they are influencing thought in environmental and medical science and systems biology.
Collapse
Affiliation(s)
- Carmel MotherSill
- McMaster Institute of Applied Radiation Sciences, McMaster University, Hamilton, Ontario, L8S 4K1, Canada.
| | - Colin Seymour
- McMaster Institute of Applied Radiation Sciences, McMaster University, Hamilton, Ontario, L8S 4K1, Canada.
| |
Collapse
|
27
|
Smith RW, Mothersill C, Hinton T, Seymour CB. Exposure to low level chronic radiation leads to adaptation to a subsequent acute X-ray dose and communication of modified acute X-ray induced bystander signals in medaka (Japanese rice fish, Oryzias latipes). Int J Radiat Biol 2011; 87:1011-22. [DOI: 10.3109/09553002.2011.587861] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Richard W. Smith
- Medical Physics and Applied Radiation Sciences, McMaster University,
Hamilton, Ontario, Canada
| | - Carmel Mothersill
- Medical Physics and Applied Radiation Sciences, McMaster University,
Hamilton, Ontario, Canada
| | - Thomas Hinton
- Laboratoire de Radioécologie et d'Ecotoxicologie IRSN/DEI/SECRE (Bâtiment 159) Institut de Radioprotection et de Sûreté Nucléaire (IRSN) Centre de Cadarache Saint Paul-lez-Durance, France
| | - Colin B. Seymour
- Medical Physics and Applied Radiation Sciences, McMaster University,
Hamilton, Ontario, Canada
| |
Collapse
|
28
|
Wang C, Smith RW, Duhig J, Prestwich WV, Byun SH, McNeill FE, Seymour CB, Mothersill CE. Neutrons do not produce a bystander effect in zebrafish irradiated in vivo. Int J Radiat Biol 2011; 87:964-73. [PMID: 21756060 DOI: 10.3109/09553002.2011.584939] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE Neutron irradiations at the McMaster Tandetron Accelerator were performed to study direct and bystander effects of neutrons in a live organism. METHODS The neutrons were produced through (7)Li(p,n)(7)Be reaction. Although the gamma contamination of the neutron beam cannot be completely eliminated, it was designed to be as low as possible and remain below a threshold already established for bystander effects. Microdosimetric methods using a tissue-equivalent proportional counter have been used to measure the neutron and gamma doses for the cell irradiation. Previous data for a cell line exposed in vitro suggested that neutrons did not produce bystander effects at doses below 300 mGy. The current experiments sought to confirm this using a live whole organism (zebrafish) where tissue samples harvested 2 h after exposure were examined for direct evidence of apoptosis and tested for secretion of bystander factors using an established bioassay. Fish were either exposed directly to the beam or were allowed to swim with or in water previously occupied by irradiated fish. RESULTS Using the zebrafish model it was found that there was significant direct cell death seen both by apoptosis scores and clonogenic assay when the neutron dose was approximately 100 mGy. An equivalent dose of gamma rays produced a more toxic effect. It was further found that neutrons did not induce a bystander effect in fish receiving signals from irradiated fish. CONCLUSION The results confirm in vitro experiments which suggest neutrons do not induce bystander signaling. In fact they may suppress gamma induced signaling suggesting a possible intriguing new and as yet unclear mechanism.
Collapse
Affiliation(s)
- Chu Wang
- Medical Physics and Applied Radiation Sciences Department, McMaster University, Hamilton, Ontario, Canada
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Proteomic changes in the gills of wild-type and transgenic radiosensitive medaka following exposure to direct irradiation and to X-ray induced bystander signals. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1814:290-8. [DOI: 10.1016/j.bbapap.2010.11.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2010] [Revised: 11/03/2010] [Accepted: 11/09/2010] [Indexed: 02/05/2023]
|
30
|
Baskar R. Emerging role of radiation induced bystander effects: Cell communications and carcinogenesis. Genome Integr 2010; 1:13. [PMID: 20831828 PMCID: PMC2949714 DOI: 10.1186/2041-9414-1-13] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Accepted: 09/12/2010] [Indexed: 02/05/2023] Open
Abstract
Ionizing radiation is an invaluable diagnostic and treatment tool used in various clinical applications. On the other hand, radiation is a known cytotoxic with a potential DNA damaging and carcinogenic effects. However, the biological effects of low and high linear energy transfer (LET) radiations are considerably more complex than previously thought. In the past decade, evidence has mounted for a novel biological phenomenon termed as "bystander effect" (BE), wherein directly irradiated cells transmit damaging signals to non-irradiated cells thereby inducing a response similar to that of irradiated cells. BE can also be induced in various cells irrespective of the type of radiation, and the BE may be more damaging in the longer term than direct radiation exposure. BE is mediated either through gap-junctions or via soluble factors released by irradiated cells. DNA damage response mechanisms represent a vital line of defense against exogenous and endogenous damage caused by radiation and promote two distinct outcomes: survival and the maintenance of genomic stability. The latter is critical for cancer avoidance. Therefore, efforts to understand and modulate the bystander responses will provide new approaches to cancer therapy and prevention. This review overviews the emerging role of BE of low and high LET radiations on the genomic instability of bystander cells and its possible implications for carcinogenesis.
Collapse
Affiliation(s)
- Rajamanickam Baskar
- Department of Radiation Oncology, Division of Cellular and Molecular Research, National Cancer Centre, Singapore.
| |
Collapse
|
31
|
Blyth BJ, Azzam EI, Howell RW, Ormsby RJ, Staudacher AH, Sykes PJ. An adoptive transfer method to detect low-dose radiation-induced bystander effects in vivo. Radiat Res 2010; 173:125-37. [PMID: 20095844 DOI: 10.1667/rr1899.1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The potential for irradiated cells to induce biological effects in their unirradiated neighbors (known as the bystander effect) has been observed repeatedly in vitro. However, whether bystander effects occur in vivo under the specific conditions relevant to low-dose radiation protection is still unclear. To test this, the fate of bystander cells in the mouse spleen was examined using an adoptive transfer method designed to replicate the rare, irradiated cells in an organ that might be expected after a low-dose-rate, low-LET radiation exposure. Splenic lymphocytes radiolabeled with low activities of (3)H-thymidine were introduced into the spleens of unirradiated recipient mice. In this study, the apoptotic and proliferative response of the neighboring bystander spleen cells was compared to the response of spleen cells in parallel control recipients that received sham-irradiated cells. Neither the local area surrounding lodged radiolabeled cells nor the spleen as a whole showed a change in apoptosis or proliferation either 1 or 3 days after adoptive transfer. Increasing the irradiated cell numbers, increasing the mean (3)H-thymidine activity per cell, or exposing cells ex vivo to an acute X-ray dose also had no effect. Possible reasons for the absence of a bystander effect in the spleen under these conditions are discussed.
Collapse
Affiliation(s)
- Benjamin J Blyth
- a Haematology and Genetic Pathology, Flinders University, Bedford Park, South Australia 5042, Australia
| | | | | | | | | | | |
Collapse
|
32
|
Asur R, Balasubramaniam M, Marples B, Thomas RA, Tucker JD. Bystander effects induced by chemicals and ionizing radiation: evaluation of changes in gene expression of downstream MAPK targets. Mutagenesis 2010; 25:271-9. [PMID: 20130020 DOI: 10.1093/mutage/geq003] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Radiation-induced bystander effects have been evaluated extensively, including the involvement of the mitogen-activated protein kinase (MAPK) pathways. However, few studies have examined the ability of chemicals to induce bystander effects, and the molecular mechanisms involved in chemical bystander effects have not been investigated. We have previously demonstrated the ability of mitomycin C (MMC) and phleomycin (PHL) to induce bystander effects in normal human lymphoblastoid cells. Here, we demonstrate changes in the expression of MAPK target genes following bystander exposure to MMC or PHL or ionizing radiation. The expression changes of 18 genes, which code for proteins that are downstream targets of MAPK proteins, were evaluated at various time points following direct or bystander exposure to MMC, PHL and ionizing radiation. The 18 genes were analysed as groups belonging to one of the seven possible combinations of the three MAPK pathways. We observed statistically significant changes in expression of several genes following exposure to each agent. However, when the expression changes were analysed in the bystander cells alone, significant increases in expression of MAPK target genes were observed for MMC- and radiation-induced bystander effects but not for PHL. PHL is an acknowledged radiomimetic agent; however, in the present study, PHL responses did not resemble those of radiation. These results provide evidence for bystander-induced changes in MAPK proteins and downstream targets and suggest that the bystander effects are a part of a general stress response.
Collapse
Affiliation(s)
- Rajalakshmi Asur
- Department of Biological Sciences, Wayne State University, 5047 Gullen Mall, Suite 1370, Detroit, MI 48202-3917, USA
| | | | | | | | | |
Collapse
|
33
|
Zhang Y, Zhou J, Baldwin J, Held KD, Prise KM, Redmond RW, Liber HL. Ionizing radiation-induced bystander mutagenesis and adaptation: quantitative and temporal aspects. Mutat Res 2009; 671:20-5. [PMID: 19695271 DOI: 10.1016/j.mrfmmm.2009.08.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Revised: 08/05/2009] [Accepted: 08/10/2009] [Indexed: 01/08/2023]
Abstract
This work explores several quantitative aspects of radiation-induced bystander mutagenesis in WTK1 human lymphoblast cells. Gamma-irradiation of cells was used to generate conditioned medium containing bystander signals, and that medium was transferred onto naïve recipient cells. Kinetic studies revealed that it required up to 1h to generate sufficient signal to induce the maximal level of mutations at the thymidine kinase locus in the bystander cells receiving the conditioned medium. Furthermore, it required at least 1h of exposure to the signal in the bystander cells to induce mutations. Bystander signal was fairly stable in the medium, requiring 12-24h to diminish. Medium that contained bystander signal was rendered ineffective by a 4-fold dilution; in contrast a greater than 20-fold decrease in the cell number irradiated to generate a bystander signal was needed to eliminate bystander-induced mutagenesis. This suggested some sort of feedback inhibition by bystander signal that prevented the signaling cells from releasing more signal. Finally, an ionizing radiation-induced adaptive response was shown to be effective in reducing bystander mutagenesis; in addition, low levels of exposure to bystander signal in the transferred medium induced adaptation that was effective in reducing mutations induced by subsequent gamma-ray exposures.
Collapse
Affiliation(s)
- Ying Zhang
- Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO 80523, USA
| | | | | | | | | | | | | |
Collapse
|
34
|
Kanasugi Y, Hamada N, Wada S, Funayama T, Sakashita T, Kakizaki T, Kobayashi Y, Takakura K. Role of DNA-PKcs in the bystander effect after low- or high-LET irradiation. Int J Radiat Biol 2009; 83:73-80. [PMID: 17357428 DOI: 10.1080/09553000601121116] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE To investigate the role of the catalytic subunit of DNA-dependent protein kinase (DNA-PKcs) in the medium-mediated bystander effect for chromosomal aberrations induced by low-linear energy transfer (LET) X-rays and high-LET heavy ions in normal human fibroblast cells. MATERIALS AND METHODS The recipient cells were treated for 12 h with conditioned medium, which was harvested from donor cells at 24 h after exposure to 10 Gy of soft X-rays (5 keV/microm) and 20Ne ions (437 keV/microm), followed by analyses of chromosome aberrations in recipient cells with premature chromosome condensation methods. To examine the role of DNA-PKcs and nitric oxide (NO), cells were treated with its inhibitor LY294002 (LY) and its scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide (c-PTIO), respectively. RESULTS Increased frequency of chromosome aberrations in recipient cells treated with conditioned medium from irradiated but not from un-irradiated donor cells was observed which was independent of radiation type. Bystander induction of chromosome aberrations in recipient cells was mitigated when donor cells were treated with LY before irradiation and with c-PTIO after irradiation, and was enhanced when recipient cells were treated with LY before treatment of recipient cells with conditioned medium from irradiated donor cells. CONCLUSION Irradiated normal human cells secrete NO and other molecules which in turn transmit radiation signals to unirradiated bystander cells, leading to the induction of bystander chromosome aberrations partially repairable by DNA-PKcs-mediated DNA damage repair machinery, such as non-homologous end-joining repair pathways.
Collapse
Affiliation(s)
- Yuichi Kanasugi
- Physics Department, International Christian University, Tokyo, Japan
| | | | | | | | | | | | | | | |
Collapse
|
35
|
Mothersill C, Smith RW, Hinton TG, Aizawa K, Seymour CB. Communication of radiation-induced signals in vivo between DNA repair deficient and proficient medaka (Oryzias latipes). ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:3335-3342. [PMID: 19534155 DOI: 10.1021/es8035219] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Radiation-induced bystander effects are established consequences of exposure to ionizing radiation. The operation of this mechanism has been seen in vitro and also between fish, mammals, and plants in vive where stress signals from treated organisms induce responses in neighbors. In vitro research shows that DNA repair deficient cells produce more toxic bystander responses. To test this in vivo two strains of Japanese medaka were tested. One is a mutant, repair deficient strain (ric2) and the other, the wildtype repair proficient strain (CAB). Irradiated fish swam with unirradiated partners in a strain mix and match protocol. The data suggest that medaka produce signals, when exposed to radiation, that induce unirradiated fish ofthe same strain swimming with them to produce an altered response to that seen in bystanders to sham irradiated fish. More apoptosis was seen in bystanders to repair deficient fish. When the strains are mixed, the bystanders of either strain respond like the donor strain. Measurements of Bcl-2 and cmyc proteins in the explants confirmed these observations. A possible role for p53 was also identified in that the use of reporters with mutant p53 demonstrated that CAB signals killed all the reporter cells by apoptosis. Use of a similar but p53 wildtype cell line had no such effect. The data add to the body of knowledge showing that bystander signals operate at hierarchical levels of organization greater than the individual and may therefore have relevance in radioecology and (eco)systems biology.
Collapse
Affiliation(s)
- C Mothersill
- McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4K1, Canada.
| | | | | | | | | |
Collapse
|
36
|
Asur RS, Thomas RA, Tucker JD. Chemical induction of the bystander effect in normal human lymphoblastoid cells. Mutat Res 2009; 676:11-6. [PMID: 19486859 DOI: 10.1016/j.mrgentox.2009.02.012] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2008] [Revised: 02/24/2009] [Accepted: 02/25/2009] [Indexed: 11/30/2022]
Abstract
Many studies investigating the bystander effect have used ionizing radiation to evaluate this phenomenon, whereas very few have determined whether genotoxic chemicals are also capable of inducing this effect. Here, we show that two such chemicals, mitomycin C, a bifunctional alkylating agent and phleomycin, a glycopeptide antibiotic of the bleomycin family, cause normal human B lymphoblastoid cells to produce media soluble factors that induce a bystander effect in unexposed cells. Ionizing radiation was used in parallel experiments to verify the existence of the bystander effect in these cells. Micronuclei in Cytochalasin B-blocked binucleated cells were used as the endpoint. Conditioned media obtained from cells exposed to mitomycin C induced a 1.5-3 fold increase, while conditioned media from phleomycin induced a 1.5-4 fold increase, and conditioned media from irradiated cells induced a 2-8 fold increase in micronuclei. We conclude that the bystander effect is not restricted to ionizing radiation, suggesting it may be a part of a general cellular stress response.
Collapse
Affiliation(s)
- Rajalakshmi S Asur
- Department of Biological Sciences, Wayne State University, Detroit, MI 48202-3917, USA
| | | | | |
Collapse
|
37
|
Edin NJ, Sandvik JA, Olsen DR, Pettersen EO. The Elimination of Low-Dose Hyper-radiosensitivity by Transfer of Irradiated-Cell Conditioned Medium Depends on Dose Rate. Radiat Res 2009; 171:22-32. [DOI: 10.1667/rr1143.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Accepted: 06/24/2008] [Indexed: 11/03/2022]
|
38
|
Zhang Y, Zhou J, Held KD, Redmond RW, Prise KM, Liber HL. Deficiencies of double-strand break repair factors and effects on mutagenesis in directly gamma-irradiated and medium-mediated bystander human lymphoblastoid cells. Radiat Res 2008; 169:197-206. [PMID: 18220473 DOI: 10.1667/rr1189.1] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2007] [Accepted: 10/02/2007] [Indexed: 11/03/2022]
Abstract
Using RNA interference techniques to knock down key proteins in two major double-strand break (DSB) repair pathways (DNA-PKcs for nonhomologous end joining, NHEJ, and Rad54 for homologous recombination, HR), we investigated the influence of DSB repair factors on radiation mutagenesis at the autosomal thymidine kinase (TK) locus both in directly irradiated cells and in unirradiated bystander cells. We also examined the role of p53 (TP53) in these processes by using cells of three human lymphoblastoid cell lines from the same donor but with differing p53 status (TK6 is p53 wild-type, NH32 is p53 null, and WTK1 is p53 mutant). Our results indicated that p53 status did not affect either the production of radiation bystander mutagenic signals or the response to these signals. In directly irradiated cells, knockdown of DNA-PKcs led to an increased mutant fraction in WTK1 cells and decreased mutant fractions in TK6 and NH32 cells. In contrast, knockdown of DNA-PKcs led to increased mutagenesis in bystander cells regardless of p53 status. In directly irradiated cells, knockdown of Rad54 led to increased induced mutant fractions in WTK1 and NH32 cells, but the knockdown did not affect mutagenesis in p53 wild-type TK6 cells. In all cell lines, Rad54 knockdown had no effect on the magnitude of bystander mutagenesis. Studies with extracellular catalase confirmed the involvement of H2O2 in bystander signaling. Our results demonstrate that DSB repair factors have different roles in mediating mutagenesis in irradiated and bystander cells.
Collapse
Affiliation(s)
- Ying Zhang
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, Colorado, USA.
| | | | | | | | | | | |
Collapse
|
39
|
Kapadia NS, Engles JM, Wahl RL. In Vitro Evaluation of Radioprotective and Radiosensitizing Effects of Rituximab. J Nucl Med 2008; 49:674-8. [DOI: 10.2967/jnumed.107.043752] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
|
40
|
Baskar R, Balajee AS, Geard CR. Effects of low and high LET radiations on bystander human lung fibroblast cell survival. Int J Radiat Biol 2007; 83:551-9. [PMID: 17613128 DOI: 10.1080/09553000701384499] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
PURPOSE This investigation is aimed to determine the role of low LET (linear energy transfer, gamma-rays) and high LET (alpha-particles) radiations on bystander effect of using the same type of cells and its implications on colony-forming efficiency from a single cell. MATERIALS AND METHODS Normal human fetal lung (MRC-5), immortalized repair deficient ataxia telangiectasia mutated (ATM) (GM5,849C) and normal (GM637H) fibroblast cells were used. Colony-forming efficiency in bystander cells (GM637H) was studied using the medium transfer technique from the two donor (MRC-5 and GM5,849C) cells and the procedure followed for bystander treatment is presented schematically in Figure 1. Evidence of change in colony formation in bystander cells, was assessed by scavenging nitric oxide (NO). RESULTS Enhancement of 10 - 30% in colony-forming efficiency was observed in bystander GM637H cells treated with irradiated conditioned medium (ICM) from MRC-5 cells collected 1 h after different doses of either gamma-rays (1, 2.5, 5 and 10 Gy) or alpha particles (0.25, 0.5, 1 and 2.5 Gy) irradiation. Similar results were obtained when ICM derived from the ATM (GM5,849C) cells. However, the stimulation was not dose dependent. Furthermore, we also show that the increase in dilutions of ICM (1:1, 1:5 and 1:10) showed an inverse correlation with cloning efficiency. Treatment of MRC-5 cells with PTIO (2-phenyl-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide) a NO scavenger, 1 h prior to irradiation reduced the enhancement of ICM mediated cell survival. CONCLUSIONS In the present study, though both the low and high LET radiations enhanced the clonogenic potential of the bystander recipient cells, medium from the ATM defective (GM5,849C) cells after gamma-irradiation showed less stimulating effect than the medium from the normal (MRC-5) cells. However, after alpha-irradiation an inverse effect was seen. NO may play an important role in enhancing the growth potential in these bystander cells.
Collapse
Affiliation(s)
- Rajamanickam Baskar
- Center for Radiological Research, Department of Radiation Oncology, College of Physicians and Surgeons, Columbia University, New York, USA.
| | | | | |
Collapse
|