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Juvkam IS, Zlygosteva O, Sitarz M, Thiede B, Sørensen BS, Malinen E, Edin NJ, Søland TM, Galtung HK. Proton Compared to X-Irradiation Induces Different Protein Profiles in Oral Cancer Cells and Their Derived Extracellular Vesicles. Int J Mol Sci 2023; 24:16983. [PMID: 38069306 PMCID: PMC10707519 DOI: 10.3390/ijms242316983] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Revised: 11/27/2023] [Accepted: 11/28/2023] [Indexed: 12/18/2023] Open
Abstract
Extracellular vesicles (EVs) are membrane-bound particles released from cells, and their cargo can alter the function of recipient cells. EVs from X-irradiated cells have been shown to play a likely role in non-targeted effects. However, EVs derived from proton irradiated cells have not yet been studied. We aimed to investigate the proteome of EVs and their cell of origin after proton or X-irradiation. The EVs were derived from a human oral squamous cell carcinoma (OSCC) cell line exposed to 0, 4, or 8 Gy from either protons or X-rays. The EVs and irradiated OSCC cells underwent liquid chromatography-mass spectrometry for protein identification. Interestingly, we found different protein profiles both in the EVs and in the OSCC cells after proton irradiation compared to X-irradiation. In the EVs, we found that protons cause a downregulation of proteins involved in cell growth and DNA damage response compared to X-rays. In the OSCC cells, proton and X-irradiation induced dissimilar cell death pathways and distinct DNA damage repair systems. These results are of potential importance for understanding how non-targeted effects in normal tissue can be limited and for future implementation of proton therapy in the clinic.
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Affiliation(s)
- Inga Solgård Juvkam
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, 0372 Oslo, Norway; (I.S.J.); (T.M.S.)
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0379 Oslo, Norway;
| | - Olga Zlygosteva
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway; (O.Z.); (N.J.E.)
| | - Mateusz Sitarz
- Danish Centre for Particle Therapy, Aarhus University Hospital, 8200 Aarhus, Denmark; (M.S.); (B.S.S.)
| | - Bernd Thiede
- Department of Biosciences, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway;
| | - Brita Singers Sørensen
- Danish Centre for Particle Therapy, Aarhus University Hospital, 8200 Aarhus, Denmark; (M.S.); (B.S.S.)
- Department of Experimental Clinical Oncology, Aarhus University Hospital, 8200 Aarhus, Denmark
| | - Eirik Malinen
- Department of Radiation Biology, Institute for Cancer Research, Oslo University Hospital, 0379 Oslo, Norway;
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway; (O.Z.); (N.J.E.)
| | - Nina Jeppesen Edin
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway; (O.Z.); (N.J.E.)
| | - Tine Merete Søland
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, 0372 Oslo, Norway; (I.S.J.); (T.M.S.)
- Department of Pathology, Oslo University Hospital, 0372 Oslo, Norway
| | - Hilde Kanli Galtung
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, 0372 Oslo, Norway; (I.S.J.); (T.M.S.)
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Zlygosteva O, Juvkam IS, Arous D, Sitarz M, Sørensen BS, Ankjærgaard C, Andersen CE, Galtung HK, Søland TM, Edin NJ, Malinen E. Acute normal tissue responses in a murine model following fractionated irradiation of the head and neck with protons or X-rays. Acta Oncol 2023; 62:1574-1580. [PMID: 37703217 DOI: 10.1080/0284186x.2023.2254481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Accepted: 08/26/2023] [Indexed: 09/15/2023]
Abstract
BACKGROUND The purpose of this study was to investigate acute normal tissue responses in the head and neck region following proton- or X-irradiation of a murine model. MATERIALS AND METHODS Female C57BL/6J mice were irradiated with protons (25 or 60 MeV) or X-rays (100 kV). The radiation field covered the oral cavity and the major salivary glands. For protons, two different treatment plans were used, either with the Bragg Peak in the middle of the mouse (BP) or outside the mouse (transmission mode; TM). Delivered physical doses were 41, 45, and 65 Gy given in 6, 7, and 10 fractions for BP, TM, and X-rays, respectively. Alanine dosimetry was used to assess delivered doses. Oral mucositis and dermatitis were scored using CTC v.2.0-based tables. Saliva was collected at baseline, right after end of irradiation, and at day 35. RESULTS The measured dose distribution for protons (TM) and X-rays was very similar. Oral mucositis appeared earlier, had a higher score and was found in a higher percentage of mice after proton irradiation compared to X-irradiation. Dermatitis, on the other hand, had a similar appearance after protons and X-rays. Compared to controls, saliva production was lower right after termination of proton- and X-irradiation. The BP group demonstrated saliva recovery compared to the TM and X-ray group at day 35. CONCLUSION With lower delivered doses, proton irradiation resulted in similar skin reactions and increased oral mucositis compared to X-irradiation. This indicates that the relative biological effectiveness of protons for acute tissue responses in the mouse head and neck is greater than the clinical standard of 1.1. Thus, there is a need for further investigations of the biological effect of protons in normal tissues.
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Affiliation(s)
- Olga Zlygosteva
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
| | - Inga Solgård Juvkam
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Delmon Arous
- Department of Medical Physics, Cancer Clinic, Oslo University Hospital, Oslo, Norway
| | - Mateusz Sitarz
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
| | - Brita Singers Sørensen
- Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark
- Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark
| | | | - Claus E Andersen
- Department of Health Technology, Technical University of Denmark, Roskilde, Denmark
| | - Hilde Kanli Galtung
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Tine Merete Søland
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
- Department of Pathology, Oslo University Hospital, Oslo, Norway
| | - Nina Jeppesen Edin
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
| | - Eirik Malinen
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, Oslo, Norway
- Department of Medical Physics, Cancer Clinic, Oslo University Hospital, Oslo, Norway
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Juvkam IS, Zlygosteva O, Arous D, Galtung HK, Malinen E, Søland TM, Edin NJ. A preclinical model to investigate normal tissue damage following fractionated radiotherapy to the head and neck. J Radiat Res 2023; 64:44-52. [PMID: 36253091 PMCID: PMC9855321 DOI: 10.1093/jrr/rrac066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/19/2022] [Revised: 08/09/2022] [Indexed: 06/16/2023]
Abstract
Radiotherapy (RT) of head and neck (H&N) cancer is known to cause both early- and late-occurring toxicities. To better appraise normal tissue responses and their dependence on treatment parameters such as radiation field and type, as well as dose and fractionation scheme, a preclinical model with relevant endpoints is required. 12-week old female C57BL/6 J mice were irradiated with 100 or 180 kV X-rays to total doses ranging from 30 to 85 Gy, given in 10 fractions over 5 days. The radiation field covered the oral cavity, swallowing structures and salivary glands. Monte Carlo simulations were employed to estimate tissue dose distribution. The follow-up period was 35 days, in order to study the early radiation-induced effects. Baseline and post irradiation investigations included macroscopic and microscopic examinations of the skin, lips, salivary glands and oral mucosa. Saliva sampling was performed to assess the salivary gland function following radiation exposure. A dose dependent radiation dermatitis in the skin was observed for doses above 30 Gy. Oral mucositis in the tongue appeared as ulcerations on the ventral surface of the tongue for doses of 75-85 Gy. The irradiated mice showed significantly reduced saliva production compared to controls. In summary, a preclinical model to investigate a broad panel of normal tissue responses following fractionated irradiation of the H&N region was established. The optimal dose to study early radiation-induced effects was found to be around 75 Gy, as this was the highest tolerated dose that gave acute effects similar to that observed in cancer patients.
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Affiliation(s)
- Inga Solgård Juvkam
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, 0372 Oslo, Norway
| | - Olga Zlygosteva
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
| | - Delmon Arous
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
- Department of Medical Physics, Cancer Clinic, Oslo University Hospital, 0379 Oslo, Norway
| | - Hilde Kanli Galtung
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, 0372 Oslo, Norway
| | - Eirik Malinen
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
- Department of Medical Physics, Cancer Clinic, Oslo University Hospital, 0379 Oslo, Norway
| | - Tine Merete Søland
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, 0372 Oslo, Norway
- Department of Pathology, Oslo University Hospital, 0372 Oslo, Norway
| | - Nina Jeppesen Edin
- Department of Physics, Faculty of Mathematics and Natural Sciences, University of Oslo, 0371 Oslo, Norway
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Mikalsen SG, Jeppesen Edin N, Sandvik JA, Pettersen EO. Separation of two sub-groups with different DNA content after treatment of T-47D breast cancer cells with low dose-rate irradiation and intermittent hypoxia. Acta Radiol 2018; 59:26-33. [PMID: 28350256 DOI: 10.1177/0284185117699999] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Background Previous studies have shown that combined treatment with internal ultra-low dose-rate irradiation selectively inactivated hypoxic T-47D breast cancer cells after three to five weeks of treatment. However, 2-3% of the hypoxic cells were found to survive and restart proliferation upon re-oxygenation. Purpose To investigate the metastatic potential and characteristics of radiosensitivity of these surviving cells, named T - 47 DS. Material and Methods The T - 47 DS cells were grown in ambient air without irradiation. A cloning experiment identified two sub-groups with different DNA content ([Formula: see text] and [Formula: see text]). Furthermore, radiosensitivity and presence of hyper-radiosensitivity (HRS) was measured by Co-60 challenge irradiation and relative migration was determined by scratch assays. Results The two subpopulations of T - 47 DS had different DNA content; one had abnormally high DNA content ([Formula: see text]) and one had DNA content similar to wild-type T-47D cells ([Formula: see text]). HRS was surprisingly present in cells of the cloned population [Formula: see text], but was absent in cells of both [Formula: see text] and T - 47 DS. The radio response of T - 47 DS, [Formula: see text] at higher radiation doses were similar to that of T-47D cells, and neither subpopulation showed increased migration compared with wild-type T-47D. Conclusion No increase in the risk of metastasis was found and only slight changes in radiosensitivity in response to conventional clinical doses was observed. Thus, the data suggest that if ultra-low dose-rate irradiation is used for targeting the hypoxic tumor fraction, conventional high dose-rate irradiation can be used to eradicate eventual surviving cells as well as cells in the well oxygenated areas of the tumor.
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Affiliation(s)
- Stine Gyland Mikalsen
- Department of Physics, University of Oslo, Oslo, Norway
- Department of Medical Physics, Oslo University Hospital, Oslo, Norway
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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] [What about the content of this article? (0)] [Affiliation(s)] [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.
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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
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Edin NJ, Christoffersen S, Fenne S, Sandvik JA, Pettersen EO. Cell inactivation by combined low dose-rate irradiation and intermittent hypoxia. Int J Radiat Biol 2014; 91:336-45. [PMID: 25510258 DOI: 10.3109/09553002.2014.996262] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To investigate in detail the earlier observed combined effect of low dose-rate β-irradiation delivered at a dose-rate of 15 mGy/h and continued intermittent hypoxia that leads to extensive cell death after approximately 3-6 weeks. MATERIAL AND METHODS Continuous low dose-rate β-irradiation at a dose rate of 15, 1.5 or 0.6 mGy/h was given by incorporation of [(3)H]-labelled valine into cellular protein. The cells were cultivated in an atmosphere with 4% O2 using an INVIVO2 hypoxia glove box. Clonogenic capacity, cell-cycle distribution and cellular respiration were monitored throughout the experiments. RESULTS After 3-6 weeks most cells died in response to the combined treatment, giving a surviving fraction of only 1-2%. However, on continued cultivation a few cells survived and restarted proliferation as the cellular oxygen supply increased with the reduced cell number. Irradiating the T-47D cells grown in an atmosphere with 4% O2 at dose-rates 10 and 25 times lower than 15 mGy/h did not have a pronounced effect on the clonogenic capacity with surviving fractions of 60-80%. CONCLUSIONS Treatment of T-47D cells with low dose-rate β-irradiation leads to a specific effect on intermittent hypoxic cells, inactivating more than 98% of the cells in the population. Given improved oxygen conditions, the few surviving cells can restart their proliferation.
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Edin NJ, Sandvik JA, Cheng C, Bergersen L, Pettersen EO. The roles of TGF-β3 and peroxynitrite in removal of hyper-radiosensitivity by priming irradiation. Int J Radiat Biol 2014; 90:527-37. [PMID: 24650070 DOI: 10.3109/09553002.2014.906767] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To investigate the mechanisms inducing and maintaining the permanent elimination of low dose hyper-radiosensitivity (HRS) in cells given a dose of 0.3 Gy at low dose-rate (LDR) (0.3 Gy/h). MATERIALS AND METHODS Two human HRS-positive cell lines (T-47D, T98G) were used. The effects of pretreatments with transforming growth factor beta (TGF-β) neutralizers, TGF-β3 or peroxynitrite scavenger on HRS were investigated using the colony assay. Cytoplasmic levels of TGF-β3 were measured using post-embedding immunogold electron microscopic analysis. RESULTS TGF-β3 neutralizer inhibited the removal of HRS by LDR irradiation. Adding 0.001 ng/ml TGF-β3 to cells removed HRS in T98G cells while 0.01 ng/ml additionally induced resistance to higher doses. Cytoplasmic levels of TGF-β3 were higher in LDR-primed cells than in unirradiated cells. The presence of the peroxynitrite scavenger uric acid inhibited the effect of LDR irradiation. Furthermore, the permanent elimination of HRS in LDR-primed cells was reversed by treatment with uric acid. The removal of HRS by medium from hypoxic cells was inhibited by adding TGF-β3 neutralizer to the medium before transfer or by adding hypoxia inducible factor 1 (HIF-1) inhibitor chetomin to the cell medium during hypoxia. CONCLUSIONS TGF-β3 is involved in the regulation of cellular responses to small doses of acute irradiation. TGF-β3 activation seems to be induced by low dose-rate irradiation by a mechanism involving inducible nitric oxide (iNOS) and peroxynitrite, or during cycling hypoxia by a mechanism most likely involving HIF-1. The study suggests methods to turn resistance to doses in the HRS-range on (by TGF-β3) or off (by TGF-β3 neutralizer or by peroxynitrite inhibition).
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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. J Radiat Res 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] [What about the content of this article? (0)] [Affiliation(s)] [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.
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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
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Edin NJ, Olsen DR, Sandvik JA, Malinen E, Pettersen EO. Low dose hyper-radiosensitivity is eliminated during exposure to cycling hypoxia but returns after reoxygenation. Int J Radiat Biol 2012; 88:311-9. [DOI: 10.3109/09553002.2012.646046] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Edin NJ, Olsen DR, Stokke T, Sandvik JA, Ebbesen P, Pettersen EO. Mechanisms of the elimination of low dose hyper-radiosensitivity in T-47D cells by low dose-rate priming. Int J Radiat Biol 2010; 85:1157-65. [DOI: 10.3109/09553000903242107] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2007] [Accepted: 06/24/2008] [Indexed: 11/03/2022]
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Edin NJ, Olsen DR, Stokke T, Pettersen EO. Recovery of low-dose hyper-radiosensitivity following a small priming dose depends on priming dose-rate. ACTA ACUST UNITED AC 2007. [DOI: 10.1504/ijlr.2007.014491] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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