Cargando…

Variation of 4 MV X-ray dose rate strongly impacts biological response both in vitro and in vivo

Whereas an RBE > 1 is described for very low-energy X-ray beams (in the range of 25–50 kV), there is a consensus that the RBE of X-rays (from 0.1 to 3 MeV) is equal to 1, whatever the energy or dose rate of the beam. Comparisons of X-ray beam dose rates are scarce even though these beams are wide...

Descripción completa

Detalles Bibliográficos
Autores principales: Ben Kacem, M., Benadjaoud, M. A., Dos Santos, M., Soysouvanh, F., Buard,  V., Tarlet, G., Le Guen, B., François, A., Guipaud, O., Milliat, F., Paget,  V.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7184727/
https://www.ncbi.nlm.nih.gov/pubmed/32341396
http://dx.doi.org/10.1038/s41598-020-64067-4
_version_ 1783526641308270592
author Ben Kacem, M.
Benadjaoud, M. A.
Dos Santos, M.
Soysouvanh, F.
Buard,  V.
Tarlet, G.
Le Guen, B.
François, A.
Guipaud, O.
Milliat, F.
Paget,  V.
author_facet Ben Kacem, M.
Benadjaoud, M. A.
Dos Santos, M.
Soysouvanh, F.
Buard,  V.
Tarlet, G.
Le Guen, B.
François, A.
Guipaud, O.
Milliat, F.
Paget,  V.
author_sort Ben Kacem, M.
collection PubMed
description Whereas an RBE > 1 is described for very low-energy X-ray beams (in the range of 25–50 kV), there is a consensus that the RBE of X-rays (from 0.1 to 3 MeV) is equal to 1, whatever the energy or dose rate of the beam. Comparisons of X-ray beam dose rates are scarce even though these beams are widely used in medical diagnosis or radiotherapy. By using two dose rates (0.63 and 2.5 Gy.min(−1)) of high-energy X-rays on normal endothelial cells (HUVECs), we have studied the clonogenic assay, but also viability/mortality, cell cycle analysis and measured cellular senescence by flow cytometry, and have performed gene analysis on custom arrays. In order to consolidate these data, we performed localized irradiation of exteriorized small intestine at 0.63 and 2.5 Gy.min(−1). Interestingly, in vivo validation has shown a significantly higher loss of weight at the higher dose when irradiating to 19 Gy a small fragment of exteriorized small intestine of C57Bl6J mice. Nevertheless, no significant differences were observed in lesioned scores between the two dose rates, while bordering epithelium staining indicated twofold greater severe damage at 2.5 Gy.min(−1) compared to 0.63 Gy.min(−1) at one week post-irradiation. Taken together, these experiments systematically show that the relative biological effectiveness of photons is different from 1 when varying the dose rate of high-energy X-rays. Moreover, these results strongly suggest that, in support of clonogenic assay, multiparametric analysis should be considered to provide an accurate evaluation of the outcome of irradiated cells.
format Online
Article
Text
id pubmed-7184727
institution National Center for Biotechnology Information
language English
publishDate 2020
publisher Nature Publishing Group UK
record_format MEDLINE/PubMed
spelling pubmed-71847272020-05-04 Variation of 4 MV X-ray dose rate strongly impacts biological response both in vitro and in vivo Ben Kacem, M. Benadjaoud, M. A. Dos Santos, M. Soysouvanh, F. Buard,  V. Tarlet, G. Le Guen, B. François, A. Guipaud, O. Milliat, F. Paget,  V. Sci Rep Article Whereas an RBE > 1 is described for very low-energy X-ray beams (in the range of 25–50 kV), there is a consensus that the RBE of X-rays (from 0.1 to 3 MeV) is equal to 1, whatever the energy or dose rate of the beam. Comparisons of X-ray beam dose rates are scarce even though these beams are widely used in medical diagnosis or radiotherapy. By using two dose rates (0.63 and 2.5 Gy.min(−1)) of high-energy X-rays on normal endothelial cells (HUVECs), we have studied the clonogenic assay, but also viability/mortality, cell cycle analysis and measured cellular senescence by flow cytometry, and have performed gene analysis on custom arrays. In order to consolidate these data, we performed localized irradiation of exteriorized small intestine at 0.63 and 2.5 Gy.min(−1). Interestingly, in vivo validation has shown a significantly higher loss of weight at the higher dose when irradiating to 19 Gy a small fragment of exteriorized small intestine of C57Bl6J mice. Nevertheless, no significant differences were observed in lesioned scores between the two dose rates, while bordering epithelium staining indicated twofold greater severe damage at 2.5 Gy.min(−1) compared to 0.63 Gy.min(−1) at one week post-irradiation. Taken together, these experiments systematically show that the relative biological effectiveness of photons is different from 1 when varying the dose rate of high-energy X-rays. Moreover, these results strongly suggest that, in support of clonogenic assay, multiparametric analysis should be considered to provide an accurate evaluation of the outcome of irradiated cells. Nature Publishing Group UK 2020-04-27 /pmc/articles/PMC7184727/ /pubmed/32341396 http://dx.doi.org/10.1038/s41598-020-64067-4 Text en © The Author(s) 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
spellingShingle Article
Ben Kacem, M.
Benadjaoud, M. A.
Dos Santos, M.
Soysouvanh, F.
Buard,  V.
Tarlet, G.
Le Guen, B.
François, A.
Guipaud, O.
Milliat, F.
Paget,  V.
Variation of 4 MV X-ray dose rate strongly impacts biological response both in vitro and in vivo
title Variation of 4 MV X-ray dose rate strongly impacts biological response both in vitro and in vivo
title_full Variation of 4 MV X-ray dose rate strongly impacts biological response both in vitro and in vivo
title_fullStr Variation of 4 MV X-ray dose rate strongly impacts biological response both in vitro and in vivo
title_full_unstemmed Variation of 4 MV X-ray dose rate strongly impacts biological response both in vitro and in vivo
title_short Variation of 4 MV X-ray dose rate strongly impacts biological response both in vitro and in vivo
title_sort variation of 4 mv x-ray dose rate strongly impacts biological response both in vitro and in vivo
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7184727/
https://www.ncbi.nlm.nih.gov/pubmed/32341396
http://dx.doi.org/10.1038/s41598-020-64067-4
work_keys_str_mv AT benkacemm variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT benadjaoudma variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT dossantosm variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT soysouvanhf variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT buardv variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT tarletg variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT leguenb variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT francoisa variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT guipaudo variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT milliatf variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo
AT pagetv variationof4mvxraydoseratestronglyimpactsbiologicalresponsebothinvitroandinvivo