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Feng H, Li W, Zhang Y, Chang C, Hua L, Feng Y, Lai Y, Geng L. Mechanistic modelling of relative biological effectiveness of carbon ion beams and comparison with experiments. Phys Med Biol 2024; 69:035020. [PMID: 38157549 DOI: 10.1088/1361-6560/ad1998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 12/29/2023] [Indexed: 01/03/2024]
Abstract
Objective.Relative biological effectiveness (RBE) plays a vital role in carbon ion radiotherapy, which is a promising treatment method for reducing toxic effects on normal tissues and improving treatment efficacy. It is important to have an effective and precise way of obtaining RBE values to support clinical decisions. A method of calculating RBE from a mechanistic perspective is reported.Approach.Ratio of dose to obtain the same number of double strand breaks (DSBs) between different radiation types was used to evaluate RBE. Package gMicroMC was used to simulate DSB yields. The DSB inductions were then analyzed to calculate RBE. The RBE values were compared with experimental results.Main results.Furusawa's experiment yielded RBE values of 1.27, 2.22, 3.00 and 3.37 for carbon ion beam with dose-averaged LET of 30.3 keVμm-1, 54.5 keVμm-1, 88 keVμm-1and 137 keVμm-1, respectively. RBE values computed from gMicroMC simulations were 1.75, 2.22, 2.87 and 2.97. When it came to a more sophisticated carbon ion beam with 6 cm spread-out Bragg peak, RBE values were 1.61, 1.63, 2.19 and 2.36 for proximal, middle, distal and distal end part, respectively. Values simulated by gMicroMC were 1.50, 1.87, 2.19 and 2.34. The simulated results were in reasonable agreement with the experimental data.Significance.As a mechanistic way for the evaluation of RBE for carbon ion radiotherapy by combining the macroscopic simulation of energy spectrum and microscopic simulation of DNA damages, this work provides a promising tool for RBE calculation supporting clinical applications such as treatment planning.
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Affiliation(s)
- Haonan Feng
- School of Physics, Beihang University, Beijing 102206, People's Republic of China
- Department of Medical Management, Chinese Academy of Science Heavy Ion Medicine (CASHIM) Co. Ltd, Beijing 100083, People's Republic of China
| | - Weiguang Li
- School of Physics, Beihang University, Beijing 102206, People's Republic of China
- Department of Medical Management, Chinese Academy of Science Heavy Ion Medicine (CASHIM) Co. Ltd, Beijing 100083, People's Republic of China
| | - Yibao Zhang
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiation Oncology, Peking University Cancer Hospital & Institute, Beijing 100142, People's Republic of China
| | - Cheng Chang
- Department of Medical Management, Chinese Academy of Science Heavy Ion Medicine (CASHIM) Co. Ltd, Beijing 100083, People's Republic of China
| | - Ling Hua
- Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Radiation Oncology, Peking University Cancer Hospital & Institute, Beijing 100142, People's Republic of China
| | - Yiwen Feng
- Beijing University of Posts and Telecommunications, Beijing 100876, People's Republic of China
| | - Youfang Lai
- Department of Medical Management, Chinese Academy of Science Heavy Ion Medicine (CASHIM) Co. Ltd, Beijing 100083, People's Republic of China
| | - LiSheng Geng
- School of Physics, Beihang University, Beijing 102206, People's Republic of China
- Peng Huanwu Collaborative Center for Research and Education, Beihang University, Beijing 100191, People's Republic of China
- Beijing Key Laboratory of Advanced Nuclear Materials and Physics, Beihang University, Beijing 102206, People's Republic of China
- Southern Center for Nuclear-Science Theory (SCNT), Institute of Modern Physics, Chinese Academy of Sciences, Huizhou 516000, Guangdong Province, People's Republic of China
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2
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Mentana A, Lamartinière Y, Orsière T, Malard V, Payet M, Slomberg D, Guardamagna I, Lonati L, Grisolia C, Jha A, Lebaron-Jacobs L, Rose J, Ottolenghi A, Baiocco G. Tritiated Steel Micro-Particles: Computational Dosimetry and Prediction of Radiation-Induced DNA Damage for In Vitro Cell Culture Exposures. Radiat Res 2023; 199:25-38. [PMID: 36442022 DOI: 10.1667/rade-22-00043.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Accepted: 10/24/2022] [Indexed: 11/30/2022]
Abstract
Biological effects of radioactive particles can be experimentally investigated in vitro as a function of particle concentration, specific activity and exposure time. However, a careful dosimetric analysis is needed to elucidate the role of radiation emitted by radioactive products in inducing cyto- and geno-toxicity: the quantification of radiation dose is essential to eventually inform dose-risk correlations. This is even more fundamental when radioactive particles are short-range emitters and when they have a chemical speciation that might further concur to the heterogeneity of energy deposition at the cellular and sub-cellular level. To this aim, we need to use computational models. In this work, we made use of a Monte Carlo radiation transport code to perform a computational dosimetric reconstruction for in vitro exposure of cells to tritiated steel particles of micrometric size. Particles of this kind have been identified as worth of attention in nuclear power industry and research: tritium easily permeates in steel elements of nuclear reactor machinery, and mechanical operations on these elements (e.g., sawing) during decommissioning of old facilities can result in particle dispersion, leading to human exposure via inhalation. Considering the software replica of a representative in vitro setup to study the effect of such particles, we therefore modelled the radiation field due to the presence of particles in proximity of cells. We developed a computational approach to reconstruct the dose range to individual cell nuclei in contact with a particle, as well as the fraction of "hit" cells and the average dose for the whole cell population, as a function of particle concentration in the culture medium. The dosimetric analysis also provided the basis to make predictions on tritium-induced DNA damage: we estimated the dose-dependent expected yield of DNA double strand breaks due to tritiated steel particle radiation, as an indicator of their expected biological effectiveness.
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Affiliation(s)
- Alice Mentana
- Laboratory of Radiation Biophysics and Radiobiology, Department of Physics, University of Pavia, Pavia, Italy
| | | | - Thierry Orsière
- Aix Marseille Univ, Avignon Université, CNRS, IRD, IMBE, Marseille, France
| | - Véronique Malard
- Aix Marseille Univ, CEA, CNRS, BIAM, Saint Paul-Lez-Durance, France
| | | | - Danielle Slomberg
- Aix Marseille Univ, CNRS, IRD, INRAE, Coll France, CEREGE, Aix-en-Provence, France
| | - Isabella Guardamagna
- Laboratory of Radiation Biophysics and Radiobiology, Department of Physics, University of Pavia, Pavia, Italy
| | - Leonardo Lonati
- Laboratory of Radiation Biophysics and Radiobiology, Department of Physics, University of Pavia, Pavia, Italy
| | | | - Awadhesh Jha
- School of Biological and Marine Sciences, University of Plymouth, Plymouth, United Kingdom
| | | | - Jerome Rose
- Aix Marseille Univ, CNRS, IRD, INRAE, Coll France, CEREGE, Aix-en-Provence, France
| | - Andrea Ottolenghi
- Laboratory of Radiation Biophysics and Radiobiology, Department of Physics, University of Pavia, Pavia, Italy
| | - Giorgio Baiocco
- Laboratory of Radiation Biophysics and Radiobiology, Department of Physics, University of Pavia, Pavia, Italy
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Matsuya Y, Kai T, Parisi A, Yoshii Y, Sato T. Application of a simple DNA damage model developed for electrons to proton irradiation. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac9a20] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2022] [Accepted: 10/13/2022] [Indexed: 01/18/2023]
Abstract
Abstract
Proton beam therapy allows irradiating tumor volumes with reduced side effects on normal tissues with respect to conventional x-ray radiotherapy. Biological effects such as cell killing after proton beam irradiations depend on the proton kinetic energy, which is intrinsically related to early DNA damage induction. As such, DNA damage estimation based on Monte Carlo simulations is a research topic of worldwide interest. Such simulation is a mean of investigating the mechanisms of DNA strand break formations. However, past modellings considering chemical processes and DNA structures require long calculation times. Particle and heavy ion transport system (PHITS) is one of the general-purpose Monte Carlo codes that can simulate track structure of protons, meanwhile cannot handle radical dynamics simulation in liquid water. It also includes a simple model enabling the efficient estimation of DNA damage yields only from the spatial distribution of ionizations and excitations without DNA geometry, which was originally developed for electron track-structure simulations. In this study, we investigated the potential application of the model to protons without any modification. The yields of single-strand breaks, double-strand breaks (DSBs) and the complex DSBs were assessed as functions of the proton kinetic energy. The PHITS-based estimation showed that the DSB yields increased as the linear energy transfer (LET) increased, and reproduced the experimental and simulated yields of various DNA damage types induced by protons with LET up to about 30 keV μm−1. These results suggest that the current DNA damage model implemented in PHITS is sufficient for estimating DNA lesion yields induced after protons irradiation except at very low energies (below 1 MeV). This model contributes to evaluating early biological impacts in radiation therapy.
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The Chromatin Architectural Protein CTCF Is Critical for Cell Survival upon Irradiation-Induced DNA Damage. Int J Mol Sci 2022; 23:ijms23073896. [PMID: 35409255 PMCID: PMC8999573 DOI: 10.3390/ijms23073896] [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: 02/27/2022] [Revised: 03/26/2022] [Accepted: 03/29/2022] [Indexed: 02/05/2023] Open
Abstract
CTCF is a nuclear protein initially discovered for its role in enhancer-promoter insulation. It has been shown to play a role in genome architecture and in fact, its DNA binding sites are enriched at the borders of chromatin domains. Recently, we showed that depletion of CTCF impairs the DNA damage response to ionizing radiation. To investigate the relationship between chromatin domains and DNA damage repair, we present here clonogenic survival assays in different cell lines upon CTCF knockdown and ionizing irradiation. The application of a wide range of ionizing irradiation doses (0–10 Gy) allowed us to investigate the survival response through a biophysical model that accounts for the double-strand breaks’ probability distribution onto chromatin domains. We demonstrate that the radiosensitivity of different cell lines is increased upon lowering the amount of the architectural protein. Our model shows that the deficiency in the DNA repair ability is related to the changes in the size of chromatin domains that occur when different amounts of CTCF are present in the nucleus.
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Kundrát P, Friedland W, Becker J, Eidemüller M, Ottolenghi A, Baiocco G. Analytical formulas representing track-structure simulations on DNA damage induced by protons and light ions at radiotherapy-relevant energies. Sci Rep 2020; 10:15775. [PMID: 32978459 PMCID: PMC7519066 DOI: 10.1038/s41598-020-72857-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 08/17/2020] [Indexed: 01/04/2023] Open
Abstract
Track structure based simulations valuably complement experimental research on biological effects of ionizing radiation. They provide information at the highest level of detail on initial DNA damage induced by diverse types of radiation. Simulations with the biophysical Monte Carlo code PARTRAC have been used for testing working hypotheses on radiation action mechanisms, for benchmarking other damage codes and as input for modelling subsequent biological processes. To facilitate such applications and in particular to enable extending the simulations to mixed radiation field conditions, we present analytical formulas that capture PARTRAC simulation results on DNA single- and double-strand breaks and their clusters induced in cells irradiated by ions ranging from hydrogen to neon at energies from 0.5 GeV/u down to their stopping. These functions offer a means by which radiation transport codes at the macroscopic scale could easily be extended to predict biological effects, exploiting a large database of results from micro-/nanoscale simulations, without having to deal with the coupling of spatial scales and running full track-structure calculations.
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Affiliation(s)
- Pavel Kundrát
- Institute of Radiation Medicine, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, Germany.,Department of Radiation Dosimetry, Nuclear Physics Institute CAS, Prague, Czech Republic
| | - Werner Friedland
- Institute of Radiation Medicine, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, Germany
| | - Janine Becker
- Institute of Radiation Medicine, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, Germany
| | - Markus Eidemüller
- Institute of Radiation Medicine, Helmholtz Zentrum München-German Research Center for Environmental Health, Neuherberg, Germany
| | - Andrea Ottolenghi
- Radiation Biophysics and Radiobiology Group, Physics Department, University of Pavia, Pavia, Italy
| | - Giorgio Baiocco
- Radiation Biophysics and Radiobiology Group, Physics Department, University of Pavia, Pavia, Italy.
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6
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Stewart RD, Carlson DJ, Butkus MP, Hawkins R, Friedrich T, Scholz M. A comparison of mechanism-inspired models for particle relative biological effectiveness (RBE). Med Phys 2018; 45:e925-e952. [PMID: 30421808 DOI: 10.1002/mp.13207] [Citation(s) in RCA: 58] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 09/05/2018] [Accepted: 09/13/2018] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND AND SIGNIFICANCE The application of heavy ion beams in cancer therapy must account for the increasing relative biological effectiveness (RBE) with increasing penetration depth when determining dose prescriptions and organ at risk (OAR) constraints in treatment planning. Because RBE depends in a complex manner on factors such as the ion type, energy, cell and tissue radiosensitivity, physical dose, biological endpoint, and position within and outside treatment fields, biophysical models reflecting these dependencies are required for the personalization and optimization of treatment plans. AIM To review and compare three mechanism-inspired models which predict the complexities of particle RBE for various ion types, energies, linear energy transfer (LET) values and tissue radiation sensitivities. METHODS The review of models and mechanisms focuses on the Local Effect Model (LEM), the Microdosimetric-Kinetic (MK) model, and the Repair-Misrepair-Fixation (RMF) model in combination with the Monte Carlo Damage Simulation (MCDS). These models relate the induction of potentially lethal double strand breaks (DSBs) to the subsequent interactions and biological processing of DSB into more lethal forms of damage. A key element to explain the increased biological effectiveness of high LET ions compared to MV x rays is the characterization of the number and local complexity (clustering) of the initial DSB produced within a cell. For high LET ions, the spatial density of DSB induction along an ion's trajectory is much greater than along the path of a low LET electron, such as the secondary electrons produced by the megavoltage (MV) x rays used in conventional radiation therapy. The main aspects of the three models are introduced and the conceptual similarities and differences are critiqued and highlighted. Model predictions are compared in terms of the RBE for DSB induction and for reproductive cell survival. RESULTS AND CONCLUSIONS Comparisons of the RBE for DSB induction and for cell survival are presented for proton (1 H), helium (4 He), and carbon (12 C) ions for the therapeutically most relevant range of ion beam energies. The reviewed models embody mechanisms of action acting over the spatial scales underlying the biological processing of potentially lethal DSB into more lethal forms of damage. Differences among the number and types of input parameters, relevant biological targets, and the computational approaches among the LEM, MK and RMF models are summarized and critiqued. Potential experiments to test some of the seemingly contradictory aspects of the models are discussed.
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Affiliation(s)
- Robert D Stewart
- Department of Radiation Oncology, University of Washington School of Medicine, 1959 NE Pacific Street, Box 356043, Seattle, WA, 98195, USA
| | - David J Carlson
- Department of Therapeutic Radiology, Yale University, New Haven, CT, USA
| | - Michael P Butkus
- Department of Therapeutic Radiology, Yale University, New Haven, CT, USA
| | - Roland Hawkins
- Radiation Oncology Center, Ochsner Clinic Foundation, New Orleans, LA, 70121, USA
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7
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Colmenares R, Krupa K, Muñoz A, Blanco F, Williart A, García G. A process to describe radiation damage at the molecular level. Application to the 125I seeds in water. Appl Radiat Isot 2018; 140:163-170. [PMID: 30015047 DOI: 10.1016/j.apradiso.2018.05.031] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 05/29/2018] [Accepted: 05/29/2018] [Indexed: 10/14/2022]
Abstract
The correlation between the absorbed energy and the induced biological damage still has unclear aspects, especially in the low energy and low dose rate irradiation regimes. From the knowledge of the molecular-induced effects (dissociations), it would be possible to better understand the side effects of radiation, such as induced cancers or damage to healthy tissue. With this in view, this paper presents results of a simulation of a 125I-seed treatment with an event-by-event MC code (LEPTS) specifically designed to account for the low energy secondary particle interactions, such as electron attachment, vibro-rotational and neutral dissociation interactions. This calculation allowed us to analyze the potential radiation damage not only in connection with the energy deposition, but also in terms of induced molecular dissociations by taking into account ionizing and non-ionizing dissociative processes. We propose that this description of the molecular level damage be the basis for nanodosimetric evaluations.
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Affiliation(s)
- R Colmenares
- Servicio de Radiofísica, Hospital Universitario Ramón y Cajal, Ctra Colmenar Viejo km 9.1, 28034 Madrid, Spain; Instituto de Física Fundamental (IFF), Consejo Superior de Investigaciones Científicas (CSIC), Serrano 113-bis, 28006 Madrid, Spain.
| | - K Krupa
- Instituto de Física Fundamental (IFF), Consejo Superior de Investigaciones Científicas (CSIC), Serrano 113-bis, 28006 Madrid, Spain
| | - A Muñoz
- Centro de Investigaciones Energéticas, Medioambientales y Tecnológicas (CIEMAT), Av. Complutense 22, 28040 Madrid, Spain
| | - F Blanco
- Departamento de Física Atómica, Molecular y Nuclear, Universidad Complutense de Madrid, 28040 Madrid, Spain
| | - A Williart
- Departamento de Física Interdisciplinar, Universidad Nacional de Educación a Distancia (UNED), Senda del Rey 9, 28040 Madrid, Spain
| | - G García
- Instituto de Física Fundamental (IFF), Consejo Superior de Investigaciones Científicas (CSIC), Serrano 113-bis, 28006 Madrid, Spain
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Manganaro L, Russo G, Bourhaleb F, Fausti F, Giordanengo S, Monaco V, Sacchi R, Vignati A, Cirio R, Attili A. 'Survival': a simulation toolkit introducing a modular approach for radiobiological evaluations in ion beam therapy. Phys Med Biol 2018. [PMID: 29537391 DOI: 10.1088/1361-6560/aab697] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
One major rationale for the application of heavy ion beams in tumour therapy is their increased relative biological effectiveness (RBE). The complex dependencies of the RBE on dose, biological endpoint, position in the field etc require the use of biophysical models in treatment planning and clinical analysis. This study aims to introduce a new software, named 'Survival', to facilitate the radiobiological computations needed in ion therapy. The simulation toolkit was written in C++ and it was developed with a modular architecture in order to easily incorporate different radiobiological models. The following models were successfully implemented: the local effect model (LEM, version I, II and III) and variants of the microdosimetric-kinetic model (MKM). Different numerical evaluation approaches were also implemented: Monte Carlo (MC) numerical methods and a set of faster analytical approximations. Among the possible applications, the toolkit was used to reproduce the RBE versus LET for different ions (proton, He, C, O, Ne) and different cell lines (CHO, HSG). Intercomparison between different models (LEM and MKM) and computational approaches (MC and fast approximations) were performed. The developed software could represent an important tool for the evaluation of the biological effectiveness of charged particles in ion beam therapy, in particular when coupled with treatment simulations. Its modular architecture facilitates benchmarking and inter-comparison between different models and evaluation approaches. The code is open source (GPL2 license) and available at https://github.com/batuff/Survival.
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Affiliation(s)
- L Manganaro
- Physics Department, Università degli studi di Torino (UniTO), Torino, Italy. Istituto Nazionale di Fisica Nucleare (INFN) Sezione di Torino, Torino, Italy. Author to whom any correspondence should be addressed
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9
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Jezkova L, Zadneprianetc M, Kulikova E, Smirnova E, Bulanova T, Depes D, Falkova I, Boreyko A, Krasavin E, Davidkova M, Kozubek S, Valentova O, Falk M. Particles with similar LET values generate DNA breaks of different complexity and reparability: a high-resolution microscopy analysis of γH2AX/53BP1 foci. NANOSCALE 2018; 10:1162-1179. [PMID: 29271466 DOI: 10.1039/c7nr06829h] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Biological effects of high-LET (linear energy transfer) radiation have received increasing attention, particularly in the context of more efficient radiotherapy and space exploration. Efficient cell killing by high-LET radiation depends on the physical ability of accelerated particles to generate complex DNA damage, which is largely mediated by LET. However, the characteristics of DNA damage and repair upon exposure to different particles with similar LET parameters remain unexplored. We employed high-resolution confocal microscopy to examine phosphorylated histone H2AX (γH2AX)/p53-binding protein 1 (53BP1) focus streaks at the microscale level, focusing on the complexity, spatiotemporal behaviour and repair of DNA double-strand breaks generated by boron and neon ions accelerated at similar LET values (∼135 keV μm-1) and low energies (8 and 47 MeV per n, respectively). Cells were irradiated using sharp-angle geometry and were spatially (3D) fixed to maximize the resolution of these analyses. Both high-LET radiation types generated highly complex γH2AX/53BP1 focus clusters with a larger size, increased irregularity and slower elimination than low-LET γ-rays. Surprisingly, neon ions produced even more complex γH2AX/53BP1 focus clusters than boron ions, consistent with DSB repair kinetics. Although the exposure of cells to γ-rays and boron ions eliminated a vast majority of foci (94% and 74%, respectively) within 24 h, 45% of the foci persisted in cells irradiated with neon. Our calculations suggest that the complexity of DSB damage critically depends on (increases with) the particle track core diameter. Thus, different particles with similar LET and energy may generate different types of DNA damage, which should be considered in future research.
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Affiliation(s)
- Lucie Jezkova
- Joint Institute for Nuclear Research, Dubna, Russia and University of Chemistry and Technology Prague, Prague, Czech Republic
- University of Chemistry and Technology Prague, Prague, Czech Republic
| | - Mariia Zadneprianetc
- Joint Institute for Nuclear Research, Dubna, Russia and Dubna State University, Dubna, Russia
- Dubna State University, Dubna, Russia
| | - Elena Kulikova
- Joint Institute for Nuclear Research, Dubna, Russia and Dubna State University, Dubna, Russia
- Dubna State University, Dubna, Russia
| | | | - Tatiana Bulanova
- Joint Institute for Nuclear Research, Dubna, Russia and Dubna State University, Dubna, Russia
- Dubna State University, Dubna, Russia
| | - Daniel Depes
- Czech Academy of Sciences, Institute of Biophysics, Brno, Czech Republic.
| | - Iva Falkova
- Czech Academy of Sciences, Institute of Biophysics, Brno, Czech Republic.
| | - Alla Boreyko
- Joint Institute for Nuclear Research, Dubna, Russia and Dubna State University, Dubna, Russia
- Dubna State University, Dubna, Russia
| | - Evgeny Krasavin
- Joint Institute for Nuclear Research, Dubna, Russia and Dubna State University, Dubna, Russia
- Dubna State University, Dubna, Russia
| | - Marie Davidkova
- Czech Academy of Sciences, Nuclear Physics Institute, Prague, Czech Republic
| | - Stanislav Kozubek
- Czech Academy of Sciences, Institute of Biophysics, Brno, Czech Republic.
| | - Olga Valentova
- University of Chemistry and Technology Prague, Prague, Czech Republic
| | - Martin Falk
- Czech Academy of Sciences, Institute of Biophysics, Brno, Czech Republic.
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10
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Friedland W, Schmitt E, Kundrát P, Dingfelder M, Baiocco G, Barbieri S, Ottolenghi A. Comprehensive track-structure based evaluation of DNA damage by light ions from radiotherapy-relevant energies down to stopping. Sci Rep 2017; 7:45161. [PMID: 28345622 PMCID: PMC5366876 DOI: 10.1038/srep45161] [Citation(s) in RCA: 132] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2016] [Accepted: 02/21/2017] [Indexed: 12/15/2022] Open
Abstract
Track structures and resulting DNA damage in human cells have been simulated for hydrogen, helium, carbon, nitrogen, oxygen and neon ions with 0.25–256 MeV/u energy. The needed ion interaction cross sections have been scaled from those of hydrogen; Barkas scaling formula has been refined, extending its applicability down to about 10 keV/u, and validated against established stopping power data. Linear energy transfer (LET) has been scored from energy deposits in a cell nucleus; for very low-energy ions, it has been defined locally within thin slabs. The simulations show that protons and helium ions induce more DNA damage than heavier ions do at the same LET. With increasing LET, less DNA strand breaks are formed per unit dose, but due to their clustering the yields of double-strand breaks (DSB) increase, up to saturation around 300 keV/μm. Also individual DSB tend to cluster; DSB clusters peak around 500 keV/μm, while DSB multiplicities per cluster steadily increase with LET. Remarkably similar to patterns known from cell survival studies, LET-dependencies with pronounced maxima around 100–200 keV/μm occur on nanometre scale for sites that contain one or more DSB, and on micrometre scale for megabasepair-sized DNA fragments.
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Affiliation(s)
- W Friedland
- Institute of Radiation Protection, Department of Radiation Sciences, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - E Schmitt
- Institute of Radiation Protection, Department of Radiation Sciences, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - P Kundrát
- Institute of Radiation Protection, Department of Radiation Sciences, Helmholtz Zentrum München - German Research Center for Environmental Health (GmbH), Neuherberg, Germany
| | - M Dingfelder
- Department of Physics, East Carolina University, Greenville, NC, USA
| | - G Baiocco
- Department of Physics, University of Pavia, Pavia, Italy
| | - S Barbieri
- Department of Physics, University of Pavia, Pavia, Italy
| | - A Ottolenghi
- Department of Physics, University of Pavia, Pavia, Italy
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11
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Baiocco G, Barbieri S, Babini G, Morini J, Alloni D, Friedland W, Kundrát P, Schmitt E, Puchalska M, Sihver L, Ottolenghi A. The origin of neutron biological effectiveness as a function of energy. Sci Rep 2016; 6:34033. [PMID: 27654349 PMCID: PMC5032018 DOI: 10.1038/srep34033] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 09/05/2016] [Indexed: 12/22/2022] Open
Abstract
The understanding of the impact of radiation quality in early and late responses of biological targets to ionizing radiation exposure necessarily grounds on the results of mechanistic studies starting from physical interactions. This is particularly true when, already at the physical stage, the radiation field is mixed, as it is the case for neutron exposure. Neutron Relative Biological Effectiveness (RBE) is energy dependent, maximal for energies ~1 MeV, varying significantly among different experiments. The aim of this work is to shed light on neutron biological effectiveness as a function of field characteristics, with a comprehensive modeling approach: this brings together transport calculations of neutrons through matter (with the code PHITS) and the predictive power of the biophysical track structure code PARTRAC in terms of DNA damage evaluation. Two different energy dependent neutron RBE models are proposed: the first is phenomenological and based only on the characterization of linear energy transfer on a microscopic scale; the second is purely ab-initio and based on the induction of complex DNA damage. Results for the two models are compared and found in good qualitative agreement with current standards for radiation protection factors, which are agreed upon on the basis of RBE data.
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Affiliation(s)
- G. Baiocco
- Department of Physics, University of Pavia, Pavia, Italy
| | - S. Barbieri
- Department of Physics, University of Pavia, Pavia, Italy
| | - G. Babini
- Department of Physics, University of Pavia, Pavia, Italy
| | - J. Morini
- Department of Physics, University of Pavia, Pavia, Italy
| | - D. Alloni
- INFN, National Institute of Nuclear Physics, Sezione di Pavia, Pavia, Italy
- LENA, Laboratory of Applied Nuclear Energy, University of Pavia, Pavia, Italy
| | - W. Friedland
- Institute of Radiation Protection, Helmholtz Zentrum München – German Research Center for Environmental Health, Neuherberg, Germany
| | - P. Kundrát
- Institute of Radiation Protection, Helmholtz Zentrum München – German Research Center for Environmental Health, Neuherberg, Germany
| | - E. Schmitt
- Institute of Radiation Protection, Helmholtz Zentrum München – German Research Center for Environmental Health, Neuherberg, Germany
| | | | - L. Sihver
- Technische Universität Wien, Wien, Austria
| | - A. Ottolenghi
- Department of Physics, University of Pavia, Pavia, Italy
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Alloni D, Baiocco G, Babini G, Friedland W, Kundrát P, Mariotti L, Ottolenghi A. Energy dependence of the complexity of DNA damage induced by carbon ions. RADIATION PROTECTION DOSIMETRY 2015; 166:86-90. [PMID: 25958411 DOI: 10.1093/rpd/ncv292] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
To assess the complexity of DNA damage induced by carbon ions as a function of their energy and LET, 2-Gy irradiations by 100 keV u(-1)-400 MeV u(-1) carbon ions were investigated using the PARTRAC code. The total number of fragments and the yield of fragments of <30 bp were calculated. The authors found a particularly important contribution of DNA fragmentation in the range of <1 kbp for specific energies of <6 MeV u(-1). They also considered the effect of different specific energies with the same LET, i.e. before and after the Bragg peak. As a first step towards a full characterisation of secondary particle production from carbon ions interacting with tissue, a comparison between DNA-damage induction by primary carbon ions and alpha particles resulting from carbon break-up is presented, for specific energies of >1 MeV u(-1).
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Affiliation(s)
- D Alloni
- Department of Physics, University of Pavia, Via Bassi 6, Pavia, Italy LENA, Laboratory of Applied Nuclear Energy, University of Pavia, Via Aselli 41, Pavia, Italy INFN National Institute of Nuclear Physics, Sezione di Pavia, Via Bassi 6, Pavia, Italy
| | - G Baiocco
- Department of Physics, University of Pavia, Via Bassi 6, Pavia, Italy INFN National Institute of Nuclear Physics, Sezione di Pavia, Via Bassi 6, Pavia, Italy
| | - G Babini
- Department of Physics, University of Pavia, Via Bassi 6, Pavia, Italy INFN National Institute of Nuclear Physics, Sezione di Pavia, Via Bassi 6, Pavia, Italy
| | - W Friedland
- Institute of Radiation Protection, Helmholtz Zentrum München, Neuherberg 85764, Germany
| | - P Kundrát
- Institute of Radiation Protection, Helmholtz Zentrum München, Neuherberg 85764, Germany
| | - L Mariotti
- Department of Physics, University of Pavia, Via Bassi 6, Pavia, Italy INFN National Institute of Nuclear Physics, Sezione di Pavia, Via Bassi 6, Pavia, Italy Department of Oncology, Gray Institute for Radiation Oncology and Biology, Old Road Campus Research Building, Off Roosevelt Drive, Oxford OX3 7DQ, UK
| | - A Ottolenghi
- Department of Physics, University of Pavia, Via Bassi 6, Pavia, Italy INFN National Institute of Nuclear Physics, Sezione di Pavia, Via Bassi 6, Pavia, Italy
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Friedland W, Kundrát P, Schmitt E. Modelling proton bunches focussed to submicrometre scales: low-LET radiation damage in high-LET-like spatial structure. RADIATION PROTECTION DOSIMETRY 2015; 166:34-37. [PMID: 25883304 DOI: 10.1093/rpd/ncv146] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Microbeam experiments approximating high-LET tracks by bunches of lower-LET particles focussed to submicrometre scales (Schmid et al. 2012, Phys. Med. Biol. 57, 5889) provide an unprecedented benchmark for models of biological effects of radiation. PARTRAC track structure-based Monte Carlo simulations have verified that focussed 20 MeV proton bunches resemble the radial dose distributions of single 55 MeV carbon ions as used in the experiments. However, the predicted yields of double-strand break and short (<1 kbp) DNA fragments by focussed protons correspond to homogeneous proton irradiation and are much smaller than for carbon tracks. The calculated yields of dicentrics overestimate the effect of focussing but reproduce the fourfold difference between carbon ions and homogeneously distributed protons. The extent to which focussed low-LET particles approximate high-LET radiation is limited by the achievable focussing: submicrometre focussing of proton bunches cannot reproduce local nanometre clustering, i.e. DNA damage complexity characteristic of high-LET radiation.
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Affiliation(s)
- W Friedland
- Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - P Kundrát
- Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - E Schmitt
- Helmholtz Zentrum München-German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
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Carante MP, Altieri S, Bortolussi S, Postuma I, Protti N, Ballarini F. Modeling radiation-induced cell death: role of different levels of DNA damage clustering. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2015; 54:305-316. [PMID: 25956821 DOI: 10.1007/s00411-015-0601-x] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2015] [Accepted: 04/28/2015] [Indexed: 06/04/2023]
Abstract
Some open questions on the mechanisms underlying radiation-induced cell death were addressed by a biophysical model, focusing on DNA damage clustering and its consequences. DNA "cluster lesions" (CLs) were assumed to produce independent chromosome fragments that, if created within a micrometer-scale threshold distance (d), can lead to chromosome aberrations following mis-rejoining; in turn, certain aberrations (dicentrics, rings and large deletions) were assumed to lead to clonogenic cell death. The CL yield and d were the only adjustable parameters. The model, implemented as a Monte Carlo code called BIophysical ANalysis of Cell death and chromosome Aberrations (BIANCA), provided simulated survival curves that were directly compared with experimental data on human and hamster cells exposed to photons, protons, α-particles and heavier ions including carbon and iron. d = 5 μm, independent of radiation quality, and CL yields in the range ~2-20 CLs Gy(-1) cell(-1), depending on particle type and energy, led to good agreement between simulations and data. This supports the hypothesis of a pivotal role of DNA cluster damage at sub-micrometric scale, modulated by chromosome fragment mis-rejoining at micrometric scale. To investigate the features of such critical damage, the CL yields were compared with experimental or theoretical yields of DNA fragments of different sizes, focusing on the base-pair scale (related to the so-called local clustering), the kbp scale ("regional clustering") and the Mbp scale, corresponding to chromatin loops. Interestingly, the CL yields showed better agreement with kbp fragments rather than bp fragments or Mbp fragments; this suggests that also regional clustering, in addition to other clustering levels, may play an important role, possibly due to its relationship with nucleosome organization in the chromatin fiber.
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Affiliation(s)
- M P Carante
- Physics Department, University of Pavia, Via Bassi 6, 27100, Pavia, Italy
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Huang YW, Pan CY, Hsiao YY, Chao TC, Lee CC, Tung CJ. Monte Carlo simulations of the relative biological effectiveness for DNA double strand breaks from 300 MeV u(-1) carbon-ion beams. Phys Med Biol 2015; 60:5995-6012. [PMID: 26183156 DOI: 10.1088/0031-9155/60/15/5995] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Monte Carlo simulations are used to calculate the relative biological effectiveness (RBE) of 300 MeV u(-1) carbon-ion beams at different depths in a cylindrical water phantom of 10 cm radius and 30 cm long. RBE values for the induction of DNA double strand breaks (DSB), a biological endpoint closely related to cell inactivation, are estimated for monoenergetic and energy-modulated carbon ion beams. Individual contributions to the RBE from primary ions and secondary nuclear fragments are simulated separately. These simulations are based on a multi-scale modelling approach by first applying the FLUKA (version 2011.2.17) transport code to estimate the absorbed doses and fluence energy spectra, then using the MCDS (version 3.10A) damage code for DSB yields. The approach is efficient since it separates the non-stochastic dosimetry problem from the stochastic DNA damage problem. The MCDS code predicts the major trends of the DSB yields from detailed track structure simulations. It is found that, as depth is increasing, RBE values increase slowly from the entrance depth to the plateau region and change substantially in the Bragg peak region. RBE values reach their maxima at the distal edge of the Bragg peak. Beyond this edge, contributions to RBE are entirely from nuclear fragments. Maximum RBE values at the distal edges of the Bragg peak and the spread-out Bragg peak are, respectively, 3.0 and 2.8. The present approach has the flexibility to weight RBE contributions from different DSB classes, i.e. DSB0, DSB+ and DSB++.
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Affiliation(s)
- Y W Huang
- Department of Medical Imaging and Radiological Sciences, College of Medicine, Chang Gung University, Kweishan Taoyuan, Taiwan
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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.
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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
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Hsiao YY, Hung TH, Tu SJ, Tung CJ. Fast Monte Carlo simulation of DNA damage induction by Auger-electron emission. Int J Radiat Biol 2014; 90:392-400. [DOI: 10.3109/09553002.2014.892649] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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A model of photon cell killing based on the spatio-temporal clustering of DNA damage in higher order chromatin structures. PLoS One 2014; 9:e83923. [PMID: 24392100 PMCID: PMC3879277 DOI: 10.1371/journal.pone.0083923] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 11/11/2013] [Indexed: 11/19/2022] Open
Abstract
We present a new approach to model dose rate effects on cell killing after photon radiation based on the spatio-temporal clustering of DNA double strand breaks (DSBs) within higher order chromatin structures of approximately 1–2 Mbp size, so called giant loops. The main concept of this approach consists of a distinction of two classes of lesions, isolated and clustered DSBs, characterized by the number of double strand breaks induced in a giant loop. We assume a low lethality and fast component of repair for isolated DSBs and a high lethality and slow component of repair for clustered DSBs. With appropriate rates, the temporal transition between the different lesion classes is expressed in terms of five differential equations. These allow formulating the dynamics involved in the competition of damage induction and repair for arbitrary dose rates and fractionation schemes. Final cell survival probabilities are computable with a cell line specific set of three parameters: The lethality for isolated DSBs, the lethality for clustered DSBs and the half-life time of isolated DSBs. By comparison with larger sets of published experimental data it is demonstrated that the model describes the cell line dependent response to treatments using either continuous irradiation at a constant dose rate or to split dose irradiation well. Furthermore, an analytic investigation of the formulation concerning single fraction treatments with constant dose rates in the limiting cases of extremely high or low dose rates is presented. The approach is consistent with the Linear-Quadratic model extended by the Lea-Catcheside factor up to the second moment in dose. Finally, it is shown that the model correctly predicts empirical findings about the dose rate dependence of incidence probabilities for deterministic radiation effects like pneumonitis and the bone marrow syndrome. These findings further support the general concepts on which the approach is based.
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Tommasino F, Friedrich T, Scholz U, Taucher-Scholz G, Durante M, Scholz M. A DNA Double-Strand Break Kinetic Rejoining Model Based on the Local Effect Model. Radiat Res 2013; 180:524-38. [DOI: 10.1667/rr13389.1] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Taleei R, Nikjoo H. Biochemical DSB-repair model for mammalian cells in G1 and early S phases of the cell cycle. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2013; 756:206-12. [DOI: 10.1016/j.mrgentox.2013.06.004] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2013] [Accepted: 06/06/2013] [Indexed: 11/24/2022]
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21
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Alloni D, Campa A, Friedland W, Mariotti L, Ottolenghi A. Integration of Monte Carlo simulations with PFGE experimental data yields constant RBE of 2.3 for DNA double-strand break induction by nitrogen ions between 125 and 225 keV/μm LET. Radiat Res 2013; 179:690-7. [PMID: 23647004 DOI: 10.1667/r3043.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The number of small radiation-induced DNA fragments can be heavily underestimated when determined from measurements of DNA mass fractions by gel electrophoresis, leading to a consequent underestimation of the initial DNA damage induction. In this study we reanalyzed the experimental results for DNA fragmentation and DNA double-strand break (DSB) yields in human fibroblasts irradiated with γ rays and nitrogen ion beams with linear energy transfer (LET) equal to 80, 125, 175 and 225 keV/μm, originally measured by Höglund et al. (Radiat Res 155, 818-825, 2001 and Int J Radiat Biol 76, 539-547, 2000). In that study the authors converted the measured distributions of fragment masses into DNA fragment distributions using mid-range values of the measured fragment length intervals, in particular they assumed fragments with lengths in the interval of 0-48 kbp had the mid-range value of 24 kbp. However, our recent detailed simulations with the Monte Carlo code PARTRAC, while reasonably in agreement with the mass distributions, indicate significantly increased yields of very short fragments by high-LET radiation, so that the actual average fragment lengths, in the interval 0-48 kbp, 2.4 kbp for 225 keV/μm nitrogen ions were much shorter than the assumed mid-range value of 24 kbp. When the measured distributions of fragment masses are converted into fragment distributions using the average fragment lengths calculated by PARTRAC, significantly higher yields of DSB related to short fragments were obtained and resulted in a constant relative biological effectiveness (RBE) for DSB induction yield of 2.3 for nitrogen ions at 125-225 keV/μm LET. The previously reported downward trend of the RBE values over this LET range for DSB induction appears to be an artifact of an inadequate average fragment length in the smallest interval.
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Affiliation(s)
- D Alloni
- Laboratory of Applied Nuclear Energy, Università degli studi di Pavia, Italy
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Single Ionization of Liquid Water by Protons, Alpha Particles, and Carbon Nuclei: Comparative Analysis of the Continuum Distorted Wave Methodologies and Empirical Models. ADVANCES IN QUANTUM CHEMISTRY 2013. [DOI: 10.1016/b978-0-12-396455-7.00008-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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23
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Sato T, Furusawa Y. Cell Survival Fraction Estimation Based on the Probability Densities of Domain and Cell Nucleus Specific Energies Using Improved Microdosimetric Kinetic Models. Radiat Res 2012; 178:341-56. [DOI: 10.1667/rr2842.1] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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24
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Champion C, Galassi ME, Weck PF, Fojón O, Hanssen J, Rivarola RD. Quantum-Mechanical Contributions to Numerical Simulations of Charged Particle Transport at the DNA Scale. RADIATION DAMAGE IN BIOMOLECULAR SYSTEMS 2012. [DOI: 10.1007/978-94-007-2564-5_16] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
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Alloni D, Campa A, Friedland W, Mariotti L, Ottolenghi A. Track structure, radiation quality and initial radiobiological events: considerations based on the PARTRAC code experience. Int J Radiat Biol 2011; 88:77-86. [PMID: 21957961 DOI: 10.3109/09553002.2011.627976] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE The role of track structures for understanding the biological effects of radiation has been the subject of research activities for decades. The physics that describes such processes is the core Monte Carlo codes, such as the biophysical PARTRAC (PARticle TRACks) code described in this review, which follow the mechanisms of radiation-matter interaction from the early stage. In this paper a review of the track structure theory (and of its possible extension concerning non-DNA targets) is presented. MATERIALS AND METHODS The role of radiation quality and track structure is analyzed starting from the heavy ions results obtained with the biophysical Monte Carlo code PARTRAC (PARticles TRACks). PARTRAC calculates DNA damage in human cells based on the superposition of simulated track structures in liquid water to an 'atom-by-atom' model of human DNA. RESULTS Calculations for DNA fragmentation compared with experimental data for different radiation qualities are illustrated. As an example, the strong dependence of the complexity of DNA damage on radiation track structure, and the very large production of very small DNA fragments (lower than 1 kbp (kilo base pairs) usually not detected experimentally) after high LET (high-Linear Energy Transfer) irradiation is shown. Furthermore the possible importance of non-nuclear/non-DNA targets is discussed in the particular case of cellular membrane and mitochondria. CONCLUSIONS The importance of the track structure is underlined, in particular the dependence of a given late cellular effect on the spatial distribution of DNA double-strand breaks (DSB) along the radiation track. These results show that the relative biological effectiveness (RBE) for DSB production can be significantly larger than 1. Moreover the cluster properties of high LET radiation may determine specific initial targets and damage evolution.
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Affiliation(s)
- Daniele Alloni
- Laboratorio Energia Nucleare Applicata, Università degli studi di Pavia, Pavia, Italy
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Bernal MA, deAlmeida CE, David M, Pires E. Estimation of the RBE of mammography-quality beams using a combination of a Monte Carlo code with a B-DNA geometrical model. Phys Med Biol 2011; 56:7393-403. [DOI: 10.1088/0031-9155/56/23/004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Friedrich T, Scholz U, Elsässer T, Durante M, Scholz M. Calculation of the biological effects of ion beams based on the microscopic spatial damage distribution pattern. Int J Radiat Biol 2011; 88:103-7. [PMID: 21823820 DOI: 10.3109/09553002.2011.611213] [Citation(s) in RCA: 138] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To present details of the recent version of the 'Local Effect Model' (LEM), that has been developed and implemented in treatment planning for the ion beam therapy pilot project performed at GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt, Germany. MATERIALS AND METHODS The new version of the model is based on a detailed consideration of the spatial distribution of the initial damages, i.e., double-strand breaks (DSB). This spatial distribution of DSB is obtained from the radial dose profile of the ion track using Monte Carlo methods. These distributions are then analyzed with regard to the proximity of DSB. This version of the model also facilitates the calculation of full dose response curves up to arbitrary high doses, thus allowing to thoroughly check the approximations previously used to estimate the quadratic term (β-term) for the linear-quadratic description of dose response curves. RESULTS The accuracy of the model predictions is demonstrated by good agreement of the relative biological effectiveness (RBE) as a function of the linear energy transfer (LET) with experimental data obtained for V79 cells after carbon irradiation. The β-values predicted by the full simulation tend to be larger as compared to the approximation in the intermediate LET range. CONCLUSION The new version of the model allows a more mechanistic description of the biological effects of ion radiation. The full simulation is a prerequisite for tests of the validity of the approach at high doses, which are of particular interest for application in hypofractionation studies.
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Affiliation(s)
- Thomas Friedrich
- GSI Helmholtzzentrum für Schwerionenforschung, Darmstadt, Germany
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28
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Bernal MA, deAlmeida CE, Sampaio C, Incerti S, Champion C, Nieminen P. The invariance of the total direct DNA strand break yield. Med Phys 2011; 38:4147-53. [DOI: 10.1118/1.3597568] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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Spotheim-Maurizot M, Davídková M. Radiation damage to DNA in DNA-protein complexes. Mutat Res 2011; 711:41-8. [PMID: 21329707 DOI: 10.1016/j.mrfmmm.2011.02.003] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2010] [Revised: 01/30/2011] [Accepted: 02/06/2011] [Indexed: 11/19/2022]
Abstract
The most aggressive product of water radiolysis, the hydroxyl (OH) radical, is responsible for the indirect effect of ionizing radiations on DNA in solution and aerobic conditions. According to radiolytic footprinting experiments, the resulting strand breaks and base modifications are inhomogeneously distributed along the DNA molecule irradiated free or bound to ligands (polyamines, thiols, proteins). A Monte-Carlo based model of simulation of the reaction of OH radicals with the macromolecules, called RADACK, allows calculating the relative probability of damage of each nucleotide of DNA irradiated alone or in complexes with proteins. RADACK calculations require the knowledge of the three dimensional structure of DNA and its complexes (determined by X-ray crystallography, NMR spectroscopy or molecular modeling). The confrontation of the calculated values with the results of the radiolytic footprinting experiments together with molecular modeling calculations show that: (1) the extent and location of the lesions are strongly dependent on the structure of DNA, which in turns is modulated by the base sequence and by the binding of proteins and (2) the regions in contact with the protein can be protected against the attack by the hydroxyl radicals via masking of the binding site and by scavenging of the radicals.
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Affiliation(s)
- M Spotheim-Maurizot
- Centre de Biophysiqe Moléculaire, CNRS, rue C. Sadron, 45071 Orléans, France
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Watanabe R, Wada S, Funayama T, Kobayashi Y, Saito K, Furusawa Y. Monte Carlo simulation of radial distribution of DNA strand breaks along the C and Ne ion paths. RADIATION PROTECTION DOSIMETRY 2011; 143:186-190. [PMID: 21224261 DOI: 10.1093/rpd/ncq539] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Radial energy deposition distribution, the distribution of DNA strand breaks and their yields were simulated by Monte Carlo track structure simulation for C and Ne ions with the same linear energy transfer (LET) around 450 keV/μm. The radial DNA damage distribution shows different pattern for C and Ne ions. Double strand break (DSB) are mostly formed in the central area, while the single strand break (SSB) tends to spread to the surrounding area. It is also shown that the production efficiency of the SSB and DSB depends on the radial distance. This result shows reasonable agreement with the recently obtained experimental observation, which indicates that different types of DNA damage shows different distribution patterns around C and Ne ion paths in cell nuclei.
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Alloni D, Campa A, Belli M, Esposito G, Mariotti L, Liotta M, Friedland W, Paretzke H, Ottolenghi A. Monte Carlo evaluation of DNA fragmentation spectra induced by different radiation qualities. RADIATION PROTECTION DOSIMETRY 2011; 143:226-231. [PMID: 21084331 DOI: 10.1093/rpd/ncq384] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The PARTRAC code has been developed constantly in the last several years. It is a Monte Carlo code based on an event-by-event description of the interactions taking place between the ionising radiation and liquid water, and in the present version simulates the transport of photons, electrons, protons, helium and heavier ions. This is combined with an atom-by-atom representation of the biological target, i.e. the DNA target model of a diploid human fibroblast in its interphase (genome of 6 Gigabase pairs). DNA damage is produced by the events of energy depositions, either directly, if they occur in the volume occupied by the sugar-phosphate backbone, or indirectly, if this volume is reached by radiation-induced radicals. This requires the determination of the probabilities of occurrence of DNA damage. Experimental data are essential for this determination. However, after the adjustment of the relevant parameters through the comparison of the simulation data with the DNA fragmentation induced by photon irradiation, the code has been used without further parameter adjustments, and the comparison with the fragmentation induced by charged particle beams has validated the code. In this paper, the results obtained for the DNA fragmentation induced by gamma rays and by charged particle beams of various LET are shown, with a particular attention to the production of very small fragments that are not detected in experiments.
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Affiliation(s)
- D Alloni
- LENA, Laboratory of Applied Nuclear Energy, University of Pavia, Pavia, Italy.
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Friedland W, Dingfelder M, Kundrát P, Jacob P. Track structures, DNA targets and radiation effects in the biophysical Monte Carlo simulation code PARTRAC. Mutat Res 2011; 711:28-40. [PMID: 21281649 DOI: 10.1016/j.mrfmmm.2011.01.003] [Citation(s) in RCA: 246] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2010] [Revised: 01/18/2011] [Accepted: 01/22/2011] [Indexed: 01/08/2023]
Abstract
This review describes the PARTRAC suite of comprehensive Monte Carlo simulation tools for calculations of track structures of a variety of ionizing radiation qualities and their biological effects. A multi-scale target model characterizes essential structures of the whole genomic DNA within human fibroblasts and lymphocytes in atomic resolution. Calculation methods and essential results are recapitulated regarding the physical, physico-chemical and chemical stage of track structure development of radiation damage induction. Recent model extension towards DNA repair processes extends the time dimension by about 12 orders of magnitude and paves the way for superior predictions of radiation risks.
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Affiliation(s)
- Werner Friedland
- Helmholtz Zentrum München, German Research Center for Environmental Health, Institute of Radiation Protection, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany.
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Toburen LH, McLawhorn SL, McLawhorn RA, Carnes KD, Dingfelder M, Shinpaugh JL. Electron emission from amorphous solid water induced by passage of energetic protons and fluorine ions. Radiat Res 2010; 174:107-18. [PMID: 20681805 PMCID: PMC3835720 DOI: 10.1667/rr1984a.1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Absolute doubly differential electron emission yields were measured from thin films of amorphous solid water (ASW) after the transmission of 6 MeV protons and 19 MeV (1 MeV/nucleon) fluorine ions. The ASW films were frozen on thin (1-microm) copper foils cooled to approximately 50 K. Electrons emitted from the films were detected as a function of angle in both the forward and backward direction and as a function of the film thickness. Electron energies were determined by measuring the ejected electron time of flight, a technique that optimizes the accuracy of measuring low-energy electron yields, where the effects of molecular environment on electron transport are expected to be most evident. Relative electron emission yields were normalized to an absolute scale by comparison of the integrated total yields for proton-induced electron emission from the copper substrate to values published previously. The absolute doubly differential yields from ASW are presented along with integrated values, providing single differential and total electron emission yields. These data may provide benchmark tests of Monte Carlo track structure codes commonly used for assessing the effects of radiation quality on biological effectiveness.
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Affiliation(s)
- L H Toburen
- Department of Physics, East Carolina University, Greenville, North Carolina 27858, USA.
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Alloni D, Campa A, Belli M, Esposito G, Facoetti A, Friedland W, Liotta M, Mariotti L, Paretzke HG, Ottolenghi A. A Monte Carlo Study of the Radiation Quality Dependence of DNA Fragmentation Spectra. Radiat Res 2010; 173:263-71. [DOI: 10.1667/rr1957.1] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Kreipl MS, Friedland W, Paretzke HG. Interaction of ion tracks in spatial and temporal proximity. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2009; 48:349-359. [PMID: 19597739 DOI: 10.1007/s00411-009-0234-z] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Accepted: 06/06/2009] [Indexed: 05/28/2023]
Abstract
In the present work, a systematic analysis of the impact of spatial and temporal proximity of ion tracks on the yield of higher-order radiolytic species as well as of DNA damage patterns is presented. This potential impact may be of concern when laser-driven particle accelerators are used for ion radiation therapy. The biophysical Monte Carlo track structure code PARTRAC was used and, to this end, extended in two aspects: first, the temporal information about track evolution has been included in the track structure module and, second, the simulation code has been modified to enable parallel multiple track processing during simulation of subsequent modelling stages. Depending on the spatial and temporal separation between ion-track pairs, the yield of chemical species has been calculated for incident protons with start energies of 20 MeV, for He(2+) ions with start energies of 1 and 20 MeV, and for 60 MeV C(6+) ions. Provided the overlap of the considered ion tracks is sufficient in all four dimensions (space and time), the yield of hydroxyl radicals was found to be reduced compared to that of single tracks, for all considered ion types. The biological endpoints investigated were base damages, single-strand breaks, double-strand breaks, and clustered lesions for incident pairs of protons and He(2+) ions, each with start energies of 20 MeV. The yield of clustered lesions produced by 20 MeV protons turned out to be influenced by the spatial separation of the proton pair; in contrast, no influence was found for different start times of the protons. The yield of single-strand breaks and base hits was found neither to depend on the spatial separation nor on the temporal separation between the incident protons. For incident 20 MeV He(2+) ions, however, a dependence on the spatial and temporal separation of the ion pair was found for all considered biological endpoints. Nevertheless, spatial proximity conditions where such intertrack effects were obtained are not met in the case of tumour radiation therapy; thus, no impact on radiation effects due to short pulse duration of laser-driven accelerators can be expected from alterations during the chemical stage.
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Affiliation(s)
- Maximilian Stephan Kreipl
- Institute of Radiation Protection, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany.
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Campa A, Alloni D, Antonelli F, Ballarini F, Belli M, Dini V, Esposito G, Facoetti A, Friedland W, Furusawa Y, Liotta M, Ottolenghi A, Paretzke HG, Simone G, Sorrentino E, Tabocchini MA. DNA Fragmentation Induced in Human Fibroblasts by56Fe Ions: Experimental Data and Monte Carlo Simulations. Radiat Res 2009; 171:438-45. [DOI: 10.1667/rr1442.1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Kreipl MS, Friedland W, Paretzke HG. Time- and space-resolved Monte Carlo study of water radiolysis for photon, electron and ion irradiation. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2009; 48:11-20. [PMID: 18949480 DOI: 10.1007/s00411-008-0194-8] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2008] [Accepted: 09/06/2008] [Indexed: 05/27/2023]
Abstract
Time-dependent yields of the most important products of water radiolysis E(aq)(-), (*)OH, H(*), H(3)O(+), H(2), OH(-) and H(2)O(2) have been calculated for (60)Co-photons, electrons, protons, helium- and carbon-ions incident onto water. G values have been evaluated for the interval from 1 ps to 1 mus after initial energy deposition as a function of time, as well as after 1 ns and at the end of the chemical stage as a function of linear energy transfer (LET), covering an interval from approximately 0.2 up to 750 keV/microm by means of different particle types. In this work, the modules of the biophysical Monte Carlo track structure code PARTRAC dealing with the simulation of prechemical and chemical stages have been improved to extend interaction data sets for heavier ions. Among other newly selected parameter values, the thermalisation distance between the point of generation and hydration of subexcitation electrons has been adopted from recent data in the literature. As far as data from the literature are available, good agreement has been found with the calculated time- and LET-dependent yields in this work, supporting the selection of the revised parameter values.
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Affiliation(s)
- Maximilian S Kreipl
- Institute of Radiation Protection, Helmholtz Zentrum München, German Research Center for Environmental Health, Ingolstädter Landstrasse 1, 85764, Neuherberg, Germany
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Kundrát P. Detailed probabilistic modelling of cell inactivation by ionizing radiations of different qualities: the model and its applications. Appl Radiat Isot 2008; 67:399-401. [PMID: 18684633 DOI: 10.1016/j.apradiso.2008.06.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The probabilistic two-stage model of cell killing by ionizing radiation enables to represent both damage induction by radiation and its repair by the cell. The model properties and applications as well as possible interpretation of the underlying damage classification are discussed. Analyses of published survival data for V79 hamster cells irradiated by protons and He, C, O, and Ne ions are reported, quantifying the variations in radiation quality with increasing charge and linear energy transfer of the ions.
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Affiliation(s)
- Pavel Kundrát
- Institute of Physics AS CR, Na Slovance 2, 18221 Prague 8, Czech Republic.
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Davídková M, Kundrát P, Stepán V, Palajová Z, Judas L. Lethal events in V79 cells irradiated by low-energy protons and correlations with distribution patterns of energy deposition, radical concentration and DNA damage. Appl Radiat Isot 2008; 67:454-9. [PMID: 18678503 DOI: 10.1016/j.apradiso.2008.06.035] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Published survival data of V79 cells irradiated by 0.5-5.0 MeV (7-40 keV/microm) protons have been analyzed with a detailed radiobiological model to estimate the per-track yields of lethal lesions. Their correlations with distribution patterns of deposited energy, radical concentrations and with the yields of specific classes of DNA damage have been studied. The observed correlations indicate a potential interpretation of DNA damage lethal for the cell and the initial physical and chemical processes leading to such damage.
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Affiliation(s)
- Marie Davídková
- Department of Radiation Dosimetry, Nuclear Physics Institute AS CR, Na Truhlárce 39/64, 18086 Prague 8, Czech Republic
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Elsässer T, Brons S, Psonka K, Scholz M, Gudowska-Nowak E, Taucher-Scholz G. Biophysical Modeling of Fragment Length Distributions of DNA Plasmids after X and Heavy-Ion Irradiation Analyzed by Atomic Force Microscopy. Radiat Res 2008; 169:649-59. [PMID: 18494540 DOI: 10.1667/rr1028.1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2007] [Accepted: 02/08/2008] [Indexed: 11/03/2022]
Affiliation(s)
- Thilo Elsässer
- Gesellschaft für Schwerionenforschung, Biophysics, Darmstadt, Germany.
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Friedland W, Paretzke HG, Ballarini F, Ottolenghi A, Kreth G, Cremer C. First steps towards systems radiation biology studies concerned with DNA and chromosome structure within living cells. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2008; 47:49-61. [PMID: 18193257 DOI: 10.1007/s00411-007-0152-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2007] [Accepted: 12/10/2007] [Indexed: 05/25/2023]
Abstract
For the understanding of radiation action on biological systems like cellular macromolecules (e.g., DNA in its higher structures) a synergistic approach of experiments and quantitative modelling of working hypotheses is necessary. Further on, the influence on calculated results of certain assumptions in such working hypotheses must critically be evaluated. In the present work, this issue is highlighted in two aspects for the case of DNA damage in single cells. First, yields of double-strand breaks and frequency distributions of DNA fragment lengths after ion irradiation were calculated using different assumptions on the DNA target model. Compared to a former target model now a moderate effect due to the inclusion of a spherical chromatin domain model has been found. Second, the influence of assumptions on particular geometric chromosome models on calculated chromosome aberration data is illustrated with two target-modelling approaches for this end point.
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Affiliation(s)
- Werner Friedland
- GSF-Forschungszentrum für Umwelt und Gesundheit, Institut für Strahlenschutz, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany.
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