1
|
Sridharan DM, Chien LC, Cucinotta FA, Pluth JM. Comparison of signaling profiles in the low dose range following low and high LET radiation. LIFE SCIENCES IN SPACE RESEARCH 2020; 25:28-41. [PMID: 32414491 DOI: 10.1016/j.lssr.2020.02.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 02/10/2020] [Accepted: 02/13/2020] [Indexed: 06/11/2023]
Abstract
During space travel astronauts will be exposed to a very low, mixed field of radiation containing different high LET particles of varying energies, over an extended period. Thus, defining how human cells respond to these complex low dose exposures is important in ascertaining risk. In the current study, we have chosen to investigate how low doses of three different ion's at various energies uniquely change the kinetics of three different phospho-proteins. A normal hTERT immortalized fibroblast cell line, 82-6, was exposed to a range of lower doses (0.05-0.5 Gy) of radiation of different qualities and energies (Si 1000 MeV/u, Si 300 MeV/u, Si 173 MeV/u, Si 93 MeV/u, Fe 1000 MeV/u, Fe 600 MeV/u, Fe 300 MeV/u, Ti 300 MeV/u, Ti 326 MeV/u, Ti 386 MeV/u), covering a wide span of LET's. Exposed samples were analyzed for the average intensity of signal as a fold over the geometric mean level of the sham controls. Three phospho-proteins known to localize to DNA DSBs following radiation (γH2AX, pATF2, pSMC1) were studied. The kinetics of their response was quantified by flow cytometery at 2 and 24 h post exposure. These studies reveal unique kinetic patterns based on the ion, energy, fluence and time following exposure. In addition, γH2AX phosphorylation patterns are uniquely different from phospho-proteins known to be primarily phosphorylated by ATM. This latter finding suggests that the activating kinase(s), or the phosphatases deactivating these proteins, exhibit differences in their response to various radiation qualities and/ or doses of exposure. Further studies will be needed to better define what the differing kinetics for the kinases activated by the unique radiation qualities plays in the biological effectiveness of the particle.
Collapse
Affiliation(s)
- Deepa M Sridharan
- Lawrence Berkeley National Laboratory, Life Sciences Division, Berkeley, CA 94710, United States
| | - Lung-Chang Chien
- Department of Environmental and Occupational Health, University of Nevada, Las Vegas, NV, 89154, United States
| | - Francis A Cucinotta
- Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, NV 89154, United States
| | - Janice M Pluth
- Health Physics and Diagnostic Sciences, University of Nevada, Las Vegas, NV 89154, United States.
| |
Collapse
|
2
|
Polymer nitric oxide donors potentiate the treatment of experimental solid tumours by increasing drug accumulation in the tumour tissue. J Control Release 2018; 269:214-224. [DOI: 10.1016/j.jconrel.2017.11.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 11/09/2017] [Accepted: 11/10/2017] [Indexed: 12/27/2022]
|
3
|
Gruel G, Villagrasa C, Voisin P, Clairand I, Benderitter M, Bottollier-Depois JF, Barquinero JF. Cell to Cell Variability of Radiation-Induced Foci: Relation between Observed Damage and Energy Deposition. PLoS One 2016; 11:e0145786. [PMID: 26727594 PMCID: PMC4699766 DOI: 10.1371/journal.pone.0145786] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Accepted: 12/08/2015] [Indexed: 11/25/2022] Open
Abstract
Most studies that aim to understand the interactions between different types of photon radiation and cellular DNA assume homogeneous cell irradiation, with all cells receiving the same amount of energy. The level of DNA damage is therefore generally determined by averaging it over the entire population of exposed cells. However, evaluating the molecular consequences of a stochastic phenomenon such as energy deposition of ionizing radiation by measuring only an average effect may not be sufficient for understanding some aspects of the cellular response to this radiation. The variance among the cells associated with this average effect may also be important for the behaviour of irradiated tissue. In this study, we accurately estimated the distribution of the number of radiation-induced γH2AX foci (RIF) per cell nucleus in a large population of endothelial cells exposed to 3 macroscopic doses of gamma rays from 60Co. The number of RIF varied significantly and reproducibly from cell to cell, with its relative standard deviation ranging from 36% to 18% depending on the macroscopic dose delivered. Interestingly, this relative cell-to-cell variability increased as the dose decreased, contrary to the mean RIF count per cell. This result shows that the dose effect, in terms of the number of DNA lesions indicated by RIF is not as simple as a purely proportional relation in which relative SD is constant with dose. To analyse the origins of this observed variability, we calculated the spread of the specific energy distribution for the different target volumes and subvolumes in which RIF can be generated. Variances, standard deviations and relative standard deviations all changed similarly from dose to dose for biological and calculated microdosimetric values. This similarity is an important argument that supports the hypothesis of the conservation of the association between the number of RIF per nucleus and the specific energy per DNA molecule. This comparison allowed us to calculate a volume of 1.6 μm3 for which the spread of the specific energy distribution could explain the entire variability of RIF counts per cell in an exposed cell population. The definition of this volume may allow to use a microdosimetric quantity to predict heterogeneity in DNA damage. Moreover, this value is consistent with the order of magnitude of the volume occupied by the hydrated sugar-phosphate backbone of the DNA molecule, which is the part of the DNA molecule responsible for strand breaks.
Collapse
Affiliation(s)
- Gaëtan Gruel
- Department of Human Health Radiation Protection, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay aux Roses, France
- * E-mail:
| | - Carmen Villagrasa
- Department of Human Health Radiation Protection, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay aux Roses, France
| | - Pascale Voisin
- Department of Human Health Radiation Protection, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay aux Roses, France
| | - Isabelle Clairand
- Department of Human Health Radiation Protection, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay aux Roses, France
| | - Marc Benderitter
- Department of Human Health Radiation Protection, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay aux Roses, France
| | - Jean-François Bottollier-Depois
- Department of Human Health Radiation Protection, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay aux Roses, France
| | - Joan Francesc Barquinero
- Department of Human Health Radiation Protection, Institut de Radioprotection et de Sûreté Nucléaire (IRSN), Fontenay aux Roses, France
| |
Collapse
|
4
|
Rouchka EC, Flight RM, Fasciotto BH, Estrada R, Eaton JW, Patibandla PK, Waigel SJ, Li D, Kirtley JK, Sethu P, Keynton RS. Transcriptional profile of immediate response to ionizing radiation exposure. GENOMICS DATA 2015; 7:82-5. [PMID: 26981369 PMCID: PMC4778620 DOI: 10.1016/j.gdata.2015.11.027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 11/30/2015] [Indexed: 01/22/2023]
Abstract
Astronauts participating in long duration space missions are likely to be exposed to ionizing radiation associated with highly energetic and charged heavy particles. Previously proposed gene biomarkers for radiation exposure include phosphorylated H2A Histone Family, Member X (γH2AX), Tumor Protein 53 (TP53), and Cyclin-Dependent Kinase Inhibitor 1A (CDKN1A). However, transcripts of these genes may not be the most suitable biomarkers for radiation exposure due to a lack of sensitivity or specificity. As part of a larger effort to develop lab-on-a-chip methods for detecting radiation exposure events using blood samples, we designed a dose–course microarray study in order to determine coding and non-coding RNA transcripts undergoing differential expression immediately following radiation exposure. The main goal was to elicit a small set of sensitive and specific radiation exposure biomarkers at low, medium, and high levels of ionizing radiation exposure. Four separate levels of radiation were considered: 0 Gray (Gy) control; 0.3 Gy; 1.5 Gy; and 3.0 Gy with four replicates at each radiation level. This report includes raw gene expression data files from the resulting microarray experiments from all three radiation levels ranging from a lower, typical exposure than an astronaut might see (0.3 Gy) to high, potentially lethal, levels of radiation (3.0 Gy). The data described here is available in NCBI's Gene Expression Omnibus (GEO), accession GSE64375.
Collapse
Affiliation(s)
- Eric C Rouchka
- Department of Computer Engineering and Computer Science, University of Louisville, Louisville, KY 40292, United States; Kentucky Biomedical Research Infrastructure Network Bioinformatics Core, University of Louisville, Louisville, KY 40292, United States
| | - Robert M Flight
- Department of Molecular and Cellular Biochemistry, University of Kentucky, Lexington, KY 40356, United States
| | - Brigitte H Fasciotto
- TheElectroOptics Research Institute and Nanotechnology Center, University of Louisville, Louisville, KY 40292, United States
| | - Rosendo Estrada
- Department of Bioengineering, University of Louisville, Louisville, KY 40292, United States
| | - John W Eaton
- Department of Medicine, University of Louisville, Louisville, KY 40292, United States; Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY 40292, United States; James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, United States
| | - Phani K Patibandla
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, United States; Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Sabine J Waigel
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY 40202, United States
| | - Dazhuo Li
- Department of Computer Engineering and Computer Science, University of Louisville, Louisville, KY 40292, United States
| | - John K Kirtley
- Department of Computer Engineering and Computer Science, University of Louisville, Louisville, KY 40292, United States
| | - Palaniappan Sethu
- Division of Cardiovascular Disease, Department of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294, United States; Department of Biomedical Engineering, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Robert S Keynton
- Department of Medicine, University of Louisville, Louisville, KY 40292, United States
| |
Collapse
|
5
|
Borràs M, Armengol G, De Cabo M, Barquinero JF, Barrios L. Comparison of methods to quantify histone H2AX phosphorylation and its usefulness for prediction of radiosensitivity. Int J Radiat Biol 2015; 91:915-24. [DOI: 10.3109/09553002.2015.1101501] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
6
|
Sridharan DM, Chappell LJ, Whalen MK, Cucinotta FA, Pluth JM. Defining the Biological Effectiveness of Components of High-LET Track Structure. Radiat Res 2015; 184:105-19. [PMID: 26114329 DOI: 10.1667/rr13684.1] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
During space travel, astronauts are exposed to a wide array of high-linear energy transfer (LET) particles, with differing energies and resulting biological effects. Risk assessment of these exposures carries a large uncertainty predominantly due to the unique track structure of the particle's energy deposition. The complex damage elicited by high charge and energy (HZE) particles results from both lesions along the track core and from energetic electrons, δ rays, generated as a consequence of particle traversal. To better define how cells respond to this complex radiation exposure, a normal hTERT immortalized skin fibroblast cell line was exposed to a defined panel of particles carefully chosen to tease out track structure effects. Phosphorylation kinetics for several key double-strand break (DSB) response proteins (γ-H2AX, pATF2 and pSMC1) were defined after exposure to ten different high-LET radiation qualities and one low-LET radiation (X ray), at two doses (0.5-2 Gy) and time points (2 and 24 h). The results reveal that the lower energy particles (Fe 300, Si 93 and Ti 300 MeV/u), with a narrower track width and higher number and intensity of δ rays, cause the highest degree of persistent damage response. The persistent γ-H2AX signal at lower energies suggests that damage from these exposures are more difficult to resolve, likely due to the greater complexity of the associated DNA lesions. However, different kinetics were observed for the solely ATM-mediated phosphorylations (pATF2 and pSMC1), revealing a shallow induction at early times and a higher level of residual phosphorylation compared to γ-H2AX. The differing phospho-protein profiles exhibited, compared to γ-H2AX, suggests additional functions for these proteins within the cell. The strong correspondence between the predicted curves for energy deposition per nucleosome for each ion/energy combination and the persistent levels of γ-H2AX indicates that the nature of energy distribution defines residual levels of γ-H2AX, an indicator of unrepaired DSBs. Our results suggest that decreasing the energy of a particle results in more complex damage that may increase genomic instability and increase the risk of carcinogenesis.
Collapse
Affiliation(s)
- Deepa M Sridharan
- a Lawrence Berkeley National Laboratory, Life Sciences Division, Berkeley, California 94710
| | - Lori J Chappell
- b NASA, Lyndon B. Johnson Space Center, Houston, Texas 77058; and
| | - Mary K Whalen
- a Lawrence Berkeley National Laboratory, Life Sciences Division, Berkeley, California 94710
| | - Francis A Cucinotta
- c University of Nevada, Las Vegas, Health Physics and Diagnostic Sciences, Las Vegas, Nevada 89154
| | - Janice M Pluth
- a Lawrence Berkeley National Laboratory, Life Sciences Division, Berkeley, California 94710
| |
Collapse
|
7
|
Tommasino F, Friedrich T, Jakob B, Meyer B, Durante M, Scholz M. Induction and Processing of the Radiation-Induced Gamma-H2AX Signal and Its Link to the Underlying Pattern of DSB: A Combined Experimental and Modelling Study. PLoS One 2015; 10:e0129416. [PMID: 26067661 PMCID: PMC4465900 DOI: 10.1371/journal.pone.0129416] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 05/10/2015] [Indexed: 12/23/2022] Open
Abstract
We present here an analysis of DSB induction and processing after irradiation with X-rays in an extended dose range based on the use of the γH2AX assay. The study was performed by quantitative flow cytometry measurements, since the use of foci counting would result in reasonable accuracy only in a limited dose range of a few Gy. The experimental data are complemented by a theoretical analysis based on the GLOBLE model. In fact, original aim of the study was to test GLOBLE predictions against new experimental data, in order to contribute to the validation of the model. Specifically, the γH2AX signal kinetics has been investigated up to 24 h after exposure to increasing photon doses between 2 and 500 Gy. The prolonged persistence of the signal at high doses strongly suggests dose dependence in DSB processing after low LET irradiation. Importantly, in the framework of our modelling analysis, this is related to a gradually increased fraction of DSB clustering at the micrometre scale. The parallel study of γH2AX dose response curves shows the onset of a pronounced saturation in two cell lines at a dose of about 20 Gy. This dose is much lower than expected according to model predictions based on the values usually adopted for the DSB induction yield (≈ 30 DSB/Gy) and for the γH2AX foci extension of approximately 2 Mbp around the DSB. We show and discuss how theoretical predictions and experimental findings can be in principle reconciled by combining an increased DSB induction yield with the assumption of a larger genomic extension for the single phosphorylated regions. As an alternative approach, we also considered in our model the possibility of a 3D spreading-mechanism of the H2AX phosphorylation around the induced DSB, and applied it to the analysis of both the aspects considered. Our results are found to be supportive for the basic assumptions on which GLOBLE is built. Apart from giving new insights into the H2AX phosphorylation process, experiments performed at high doses are of relevance in the context of radiation therapy, where hypo-fractionated schemes become increasingly popular.
Collapse
Affiliation(s)
- Francesco Tommasino
- GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany
- * E-mail:
| | - Thomas Friedrich
- GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany
| | - Burkhard Jakob
- GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany
| | - Barbara Meyer
- GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany
- Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Marco Durante
- GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany
- Technische Universität Darmstadt, Institut für Festkörperphysik, Darmstadt, Germany
| | - Michael Scholz
- GSI Helmholtzzentrum für Schwerionenforschung, Department of Biophysics, Darmstadt, Germany
| |
Collapse
|
8
|
Wang D, Zhu L, Chen JF, Dai L. Can graphene quantum dots cause DNA damage in cells? NANOSCALE 2015; 7:9894-901. [PMID: 25967921 DOI: 10.1039/c5nr01734c] [Citation(s) in RCA: 81] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Graphene quantum dots (GQDs) have attracted tremendous attention for biological applications. We report the first study on cytotoxicity and genotoxicity of GQDs to fibroblast cell lines (NIH-3T3 cells). The NIH-3T3 cells treated with GQDs at dosages over 50 μg mL(-1) showed no significant cytotoxicity. However, the GQD-treated NIH-3T3 cells exhibited an increased expression of proteins (p53, Rad 51, and OGG1) related to DNA damage compared with untreated cells, indicating the DNA damage caused by GQDs. The GQD-induced release of reactive oxygen species (ROS) was demonstrated to be responsible for the observed DNA damage. These findings should have important implications for future applications of GQDs in biological systems.
Collapse
Affiliation(s)
- Dan Wang
- State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing 100029, China.
| | | | | | | |
Collapse
|
9
|
BECK MICHAËL, ROMBOUTS CHARLOTTE, MOREELS MARJAN, AERTS AN, QUINTENS ROEL, TABURY KEVIN, MICHAUX ARLETTE, JANSSEN ANN, NEEFS MIEKE, ERNST ERIC, DIERIKS BIRGER, LEE RYONFA, DE VOS WINNOKH, LAMBERT CHARLES, VAN OOSTVELDT PATRICK, BAATOUT SARAH. Modulation of gene expression in endothelial cells in response to high LET nickel ion irradiation. Int J Mol Med 2014; 34:1124-32. [DOI: 10.3892/ijmm.2014.1893] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Accepted: 05/06/2014] [Indexed: 11/06/2022] Open
|
10
|
Sasaki MS, Tachibana A, Takeda S. Cancer risk at low doses of ionizing radiation: artificial neural networks inference from atomic bomb survivors. JOURNAL OF RADIATION RESEARCH 2014; 55:391-406. [PMID: 24366315 PMCID: PMC4014156 DOI: 10.1093/jrr/rrt133] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/04/2013] [Revised: 10/20/2013] [Accepted: 10/22/2013] [Indexed: 06/03/2023]
Abstract
Cancer risk at low doses of ionizing radiation remains poorly defined because of ambiguity in the quantitative link to doses below 0.2 Sv in atomic bomb survivors in Hiroshima and Nagasaki arising from limitations in the statistical power and information available on overall radiation dose. To deal with these difficulties, a novel nonparametric statistics based on the 'integrate-and-fire' algorithm of artificial neural networks was developed and tested in cancer databases established by the Radiation Effects Research Foundation. The analysis revealed unique features at low doses that could not be accounted for by nominal exposure dose, including (i) the presence of a threshold that varied with organ, gender and age at exposure, and (ii) a small but significant bumping increase in cancer risk at low doses in Nagasaki that probably reflects internal exposure to (239)Pu. The threshold was distinct from the canonical definition of zero effect in that it was manifested as negative excess relative risk, or suppression of background cancer rates. Such a unique tissue response at low doses of radiation exposure has been implicated in the context of the molecular basis of radiation-environment interplay in favor of recently emerging experimental evidence on DNA double-strand break repair pathway choice and its epigenetic memory by histone marking.
Collapse
Affiliation(s)
- Masao S. Sasaki
- Kyoto University, 17-12 Shironosato, Nagaokakyo-shi, Kyoto 617-0835, Japan
| | - Akira Tachibana
- Department of Biology, Faculty of Science, Ibaraki University, Bunkyo 2-1-1, Mito, Ibaraki 310-8512, Japan
| | - Shunichi Takeda
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshida-konoecho, Sakyo-ku, Kyoto 606-8501, Japan
| |
Collapse
|
11
|
Ghosh S, Narang H, Sarma A, Krishna M. DNA damage response signaling in lung adenocarcinoma A549 cells following gamma and carbon beam irradiation. Mutat Res 2011; 716:10-19. [PMID: 21839752 DOI: 10.1016/j.mrfmmm.2011.07.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2011] [Revised: 07/22/2011] [Accepted: 07/26/2011] [Indexed: 05/31/2023]
Abstract
Carbon beams (5.16MeV/u, LET=290keV/μm) are high linear energy transfer (LET) radiation characterized by higher relative biological effectiveness than low LET radiation. The aim of the current study was to determine the signaling differences between γ-rays and carbon ion-irradiation. A549 cells were irradiated with 1Gy carbon or γ-rays. Carbon beam was found to be three times more cytotoxic than γ-rays despite the fact that the numbers of γ-H2AX foci were same. Percentage of cells showing ATM/ATR foci were more with γ-rays however number of foci per cell were more in case of carbon irradiation. Large BRCA1 foci were found in all carbon irradiated cells unlike γ-rays irradiated cells and prosurvival ERK pathway was activated after γ-rays irradiation but not carbon. The noteworthy finding of this study is the early phase apoptosis induction by carbon ions. In the present study in A549 lung adenocarcinoma, authors conclude that despite activation of same repair molecules such as ATM and BRCA1, differences in low and high LET damage responses might be due to their distinct macromolecular complexes rather than their individual activation and the activation of cytoplasmic pathways such as ERK, whether it applies to all the cell lines need to be further explored.
Collapse
Affiliation(s)
- Somnath Ghosh
- Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Trombay, Mumbai, India
| | | | | | | |
Collapse
|
12
|
Buonanno M, de Toledo SM, Azzam EI. Increased frequency of spontaneous neoplastic transformation in progeny of bystander cells from cultures exposed to densely ionizing radiation. PLoS One 2011; 6:e21540. [PMID: 21738697 PMCID: PMC3125249 DOI: 10.1371/journal.pone.0021540] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2011] [Accepted: 06/01/2011] [Indexed: 11/18/2022] Open
Abstract
An increased risk of carcinogenesis caused by exposure to space radiation during prolonged space travel is a limiting factor for human space exploration. Typically, astronauts are exposed to low fluences of ionizing particles that target only a few cells in a tissue at any one time. The propagation of stressful effects from irradiated to neighboring bystander cells and their transmission to progeny cells would be of importance in estimates of the health risks of exposure to space radiation. With relevance to the risk of carcinogenesis, we investigated, in model C3H 10T½ mouse embryo fibroblasts (MEFs), modulation of the spontaneous frequency of neoplastic transformation in the progeny of bystander MEFs that had been in co-culture 10 population doublings earlier with MEFs exposed to moderate doses of densely ionizing iron ions (1 GeV/nucleon) or sparsely ionizing protons (1 GeV). An increase (P<0.05) in neoplastic transformation frequency, likely mediated by intercellular communication through gap junctions, was observed in the progeny of bystander cells that had been in co-culture with cells irradiated with iron ions, but not with protons.
Collapse
Affiliation(s)
- Manuela Buonanno
- Department of Radiology, University of Medicine and Dentistry of New Jersey (UMDNJ), New Jersey Medical School Cancer Center, Newark, New Jersey, United States of America
- University of Medicine and Dentistry of New Jersey (UMDNJ), Graduate School of Biomedical Sciences, Newark, New Jersey, United States of America
| | - Sonia M. de Toledo
- Department of Radiology, University of Medicine and Dentistry of New Jersey (UMDNJ), New Jersey Medical School Cancer Center, Newark, New Jersey, United States of America
| | - Edouard I. Azzam
- Department of Radiology, University of Medicine and Dentistry of New Jersey (UMDNJ), New Jersey Medical School Cancer Center, Newark, New Jersey, United States of America
- University of Medicine and Dentistry of New Jersey (UMDNJ), Graduate School of Biomedical Sciences, Newark, New Jersey, United States of America
- * E-mail:
| |
Collapse
|