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Glowa C, Bendinger AL, Euler-Lange R, Peschke P, Brons S, Debus J, Karger CP. Irradiation with Carbon Ions Effectively Counteracts Hypoxia-related Radioresistance in a Rat Prostate Carcinoma. Int J Radiat Oncol Biol Phys 2024; 120:875-883. [PMID: 38750905 DOI: 10.1016/j.ijrobp.2024.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 04/29/2024] [Accepted: 05/06/2024] [Indexed: 06/04/2024]
Abstract
PURPOSE Hypoxia in tumors is associated with increased malignancy and resistance to conventional photon radiation therapy. This study investigated the potential of particle therapy to counteract radioresistance in syngeneic rat prostate carcinoma. METHODS AND MATERIALS Subcutaneously transplanted R3327-HI tumors were irradiated with photons or carbon ions under acute hypoxic conditions, induced by clamping the tumor-supplying artery 10 min before and during irradiation. Dose-response curves were determined for the endpoint "local tumor control within 300 days" and compared with previously published data acquired under oxic conditions. Doses at 50% tumor control probability (TCD50) were used to quantify hypoxia-induced radioresistance relative to that under oxic conditions and also to quantify the increased effectiveness of carbon ions under oxic and hypoxic conditions relative to photons. RESULTS Compared with those under oxic conditions, TCD50 values under hypoxic conditions increased by a factor of 1.53 ± 0.08 for photons and by a factor of 1.28 ± 0.06 for carbon ions (oxygen enhancement ratio). Compared with those for photons, TCD50 values for carbon ions decreased by a factor of 2.08 ± 0.13 under oxic conditions and by a factor of 2.49 ± 0.08 under hypoxic conditions (relative biological effectiveness). While the slope of the photon dose-response curves increased when changing from oxic to hypoxic conditions, the slopes were steeper and remained unchanged for carbon ions. CONCLUSIONS The reduced oxygen enhancement ratio of carbon ions indicated that the required dose increase in hypoxic tumors was 17% lower for carbon ions than for photons. Additionally, carbon ions reduced the effect of intertumor heterogeneity on the radiation response. Therefore, carbon ions may confer a significant advantage for the treatment of hypoxic tumors that are highly resistant to conventional photon radiation therapy.
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Affiliation(s)
- Christin Glowa
- Department of Radiation Oncology and Radiotherapy, University Hospital Heidelberg, Heidelberg, Germany; Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Alina L Bendinger
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany; University of Heidelberg, Faculty of Biosciences, Heidelberg, Germany
| | - Rosemarie Euler-Lange
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany; Department of Radiooncology/Radiobiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Peter Peschke
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Stephan Brons
- Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany; Heidelberg Ion Beam Therapy Center (HIT), Heidelberg, Germany
| | - Jürgen Debus
- Department of Radiation Oncology and Radiotherapy, University Hospital Heidelberg, Heidelberg, Germany; Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany; Clinical Cooperation Unit Radiation Therapy, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Christian P Karger
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany; Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.
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2
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Ito A, Kitabatake S, Furuichi W, Takase N, Nakahara T, Akiyama T, Yoshida S, Kusano Y, Furusawa Y, Hirayama R. LET Dependence of 8-Hydroxy-2'-deoxyguanosine (8-OHdG) Generation in Mammalian Cells under Air-Saturated and Hypoxic Conditions: A Possible Experimental Approach to the Mechanism of the Decreasing Oxygen Effect in the High-LET Region. Radiat Res 2024; 201:189-196. [PMID: 38294870 DOI: 10.1667/rade-23-00046.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Accepted: 01/22/2024] [Indexed: 02/01/2024]
Abstract
One of the most distinguished features in biological effects of heavy ions would be the decrease of oxygen effect in the high-LET region. This feature has been referred to as the radiobiological basis for the control of hypoxic fraction in cancer radiotherapy. However, mechanisms to explain this phenomenon have not been fully understood. One of the explanations was given by the oxygen in the track hypothesis, which proposes that oxygen is produced along ion tracks even in the hypoxic irradiation condition. In the present study, we designed an experimental approach to support this hypothesis by using 8-hydroxy-2'-deoxyguanosine (8-OHdG) as DNA damage requiring oxygen to produce. The LET dependence of 8-OHdG under hypoxic condition revealed that with increasing LET 8-OHdG yield seems to increase, despite that the yield of OH radical, which is also required for the production of 8-OHdG, decreases in the high-LET region. This result is consistent with the explanation that the local generation of oxygen along ion tracks contributes to the increase of 8-OHdG yield.
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Affiliation(s)
- A Ito
- Department of Nuclear Engineering, School of Engineering, Tokai University, Kanagawa, Japan
| | - S Kitabatake
- Department of Nuclear Engineering, School of Engineering, Tokai University, Kanagawa, Japan
| | - W Furuichi
- Department of Nuclear Engineering, School of Engineering, Tokai University, Kanagawa, Japan
| | - N Takase
- Department of Nuclear Engineering, School of Engineering, Tokai University, Kanagawa, Japan
| | - T Nakahara
- Department of Nuclear Engineering, School of Engineering, Tokai University, Kanagawa, Japan
| | - T Akiyama
- Department of Nuclear Engineering, School of Engineering, Tokai University, Kanagawa, Japan
| | - S Yoshida
- Department of Nuclear Engineering, School of Engineering, Tokai University, Kanagawa, Japan
| | - Y Kusano
- Department of Nuclear Engineering, School of Engineering, Tokai University, Kanagawa, Japan
- Section of Medical Physics and Engineering, Kanagawa Cancer Center, Kanagawa, Japan
| | - Y Furusawa
- Department of Charged Particle Therapy Research, Institute for Quantum Medical Science, National Institutes Quantum Science and Technology, Chiba, Japan
| | - R Hirayama
- Department of Charged Particle Therapy Research, Institute for Quantum Medical Science, National Institutes Quantum Science and Technology, Chiba, Japan
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3
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Imaizumi A, Hirayama R, Ikoma Y, Nitta N, Obata T, Hasegawa S. Neon ion ( 20 Ne 10 + ) charged particle beams manipulate rapid tumor reoxygenation in syngeneic mouse models. Cancer Sci 2024; 115:227-236. [PMID: 37994570 PMCID: PMC10823265 DOI: 10.1111/cas.16017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 10/28/2023] [Accepted: 11/01/2023] [Indexed: 11/24/2023] Open
Abstract
Charged particle beams induce various biological effects by creating high-density ionization through the deposition of energy along the beam's trajectory. Charged particle beams composed of neon ions (20 Ne10+ ) hold great potential for biomedical applications, but their physiological effects on living organs remain uncertain. In this study, we demonstrate that neon-ion beams expedite the process of reoxygenation in tumor models. We simulated mouse SCCVII syngeneic tumors and exposed them to either X-ray or neon-ion beams. Through an in vivo radiobiological assay, we observed a reduction in the hypoxic fraction in tumors irradiated with 8.2 Gy of neon-ion beams 30 h after irradiation compared to 6 h post-irradiation. Conversely, no significant changes in hypoxia were observed in tumors irradiated with 8.2 Gy of X-rays. To directly quantify hypoxia in the irradiated living tumors, we utilized dynamic contrast-enhanced magnetic resonance imaging (MRI) and diffusion-weighted imaging. These combined MRI techniques revealed that the non-hypoxic fraction in neon-irradiated tumors was significantly higher than that in X-irradiated tumors (69.53% vs. 47.67%). Simultaneously, the hypoxic fraction in neon-ion-irradiated tumors (2.77%) was lower than that in X-irradiated tumors (4.27%) and non-irradiated tumors (32.44%). These results support the notion that accelerated reoxygenation occurs more effectively with neon-ion beam irradiation compared to X-rays. These findings shed light on the physiological effects of neon-ion beams on tumors and their microenvironment, emphasizing the therapeutic advantage of using neon-ion charged particle beams to manipulate tumor reoxygenation.
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Affiliation(s)
- Akiko Imaizumi
- Department of Molecular Imaging and TheranosticsNational Institutes for Quantum Science and TechnologyChibaJapan
- Present address:
Department of Dental Radiology and Radiation OncologyTokyo Medical and Dental UniversityTokyoJapan
| | - Ryoichi Hirayama
- Department of Charged Particle Therapy ResearchNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Yoko Ikoma
- Department of Molecular Imaging and TheranosticsNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Nobuhiro Nitta
- Department of Molecular Imaging and TheranosticsNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Takayuki Obata
- Department of Molecular Imaging and TheranosticsNational Institutes for Quantum Science and TechnologyChibaJapan
| | - Sumitaka Hasegawa
- Department of Charged Particle Therapy ResearchNational Institutes for Quantum Science and TechnologyChibaJapan
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4
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Helm A, Fournier C. High-LET charged particles: radiobiology and application for new approaches in radiotherapy. Strahlenther Onkol 2023; 199:1225-1241. [PMID: 37872399 PMCID: PMC10674019 DOI: 10.1007/s00066-023-02158-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2023] [Accepted: 09/17/2023] [Indexed: 10/25/2023]
Abstract
The number of patients treated with charged-particle radiotherapy as well as the number of treatment centers is increasing worldwide, particularly regarding protons. However, high-linear energy transfer (LET) particles, mainly carbon ions, are of special interest for application in radiotherapy, as their special physical features result in high precision and hence lower toxicity, and at the same time in increased efficiency in cell inactivation in the target region, i.e., the tumor. The radiobiology of high-LET particles differs with respect to DNA damage repair, cytogenetic damage, and cell death type, and their increased LET can tackle cells' resistance to hypoxia. Recent developments and perspectives, e.g., the return of high-LET particle therapy to the US with a center planned at Mayo clinics, the application of carbon ion radiotherapy using cost-reducing cyclotrons and the application of helium is foreseen to increase the interest in this type of radiotherapy. However, further preclinical research is needed to better understand the differential radiobiological mechanisms as opposed to photon radiotherapy, which will help to guide future clinical studies for optimal exploitation of high-LET particle therapy, in particular related to new concepts and innovative approaches. Herein, we summarize the basics and recent progress in high-LET particle radiobiology with a focus on carbon ions and discuss the implications of current knowledge for charged-particle radiotherapy. We emphasize the potential of high-LET particles with respect to immunogenicity and especially their combination with immunotherapy.
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Affiliation(s)
- Alexander Helm
- Biophysics Department, GSI Helmholtz Center for Heavy Ion Research, Darmstadt, Germany
| | - Claudia Fournier
- Biophysics Department, GSI Helmholtz Center for Heavy Ion Research, Darmstadt, Germany.
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5
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Coll RP, Bright SJ, Martinus DKJ, Georgiou DK, Sawakuchi GO, Manning HC. Alpha Particle-Emitting Radiopharmaceuticals as Cancer Therapy: Biological Basis, Current Status, and Future Outlook for Therapeutics Discovery. Mol Imaging Biol 2023; 25:991-1019. [PMID: 37845582 DOI: 10.1007/s11307-023-01857-y] [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: 06/26/2023] [Revised: 09/03/2023] [Accepted: 09/05/2023] [Indexed: 10/18/2023]
Abstract
Critical advances in radionuclide therapy have led to encouraging new options for cancer treatment through the pairing of clinically useful radiation-emitting radionuclides and innovative pharmaceutical discovery. Of the various subatomic particles used in therapeutic radiopharmaceuticals, alpha (α) particles show great promise owing to their relatively large size, delivered energy, finite pathlength, and resulting ionization density. This review discusses the therapeutic benefits of α-emitting radiopharmaceuticals and their pairing with appropriate diagnostics, resulting in innovative "theranostic" platforms. Herein, the current landscape of α particle-emitting radionuclides is described with an emphasis on their use in theranostic development for cancer treatment. Commonly studied radionuclides are introduced and recent efforts towards their production for research and clinical use are described. The growing popularity of these radionuclides is explained through summarizing the biological effects of α radiation on cancer cells, which include DNA damage, activation of discrete cell death programs, and downstream immune responses. Examples of efficient α-theranostic design are described with an emphasis on strategies that lead to cellular internalization and the targeting of proteins involved in therapeutic resistance. Historical barriers to the clinical deployment of α-theranostic radiopharmaceuticals are also discussed. Recent progress towards addressing these challenges is presented along with examples of incorporating α-particle therapy in pharmaceutical platforms that can be easily converted into diagnostic counterparts.
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Affiliation(s)
- Ryan P Coll
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, 1881 East Rd, Houston, TX, 77054, USA
| | - Scott J Bright
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 6565 MD Anderson Blvd, Houston, TX, 77030, USA
| | - David K J Martinus
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 6565 MD Anderson Blvd, Houston, TX, 77030, USA
| | - Dimitra K Georgiou
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, 1881 East Rd, Houston, TX, 77054, USA
| | - Gabriel O Sawakuchi
- Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, 6565 MD Anderson Blvd, Houston, TX, 77030, USA
| | - H Charles Manning
- Department of Cancer Systems Imaging, The University of Texas MD Anderson Cancer Center, 1881 East Rd, Houston, TX, 77054, USA.
- Cyclotron Radiochemistry Facility, The University of Texas MD Anderson Cancer Center, 1881 East Rd, Houston, TX, 77054, USA.
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6
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Sokol O, Durante M. Carbon Ions for Hypoxic Tumors: Are We Making the Most of Them? Cancers (Basel) 2023; 15:4494. [PMID: 37760464 PMCID: PMC10526811 DOI: 10.3390/cancers15184494] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 09/07/2023] [Accepted: 09/07/2023] [Indexed: 09/29/2023] Open
Abstract
Hypoxia, which is associated with abnormal vessel growth, is a characteristic feature of many solid tumors that increases their metastatic potential and resistance to radiotherapy. Carbon-ion radiation therapy, either alone or in combination with other treatments, is one of the most promising treatments for hypoxic tumors because the oxygen enhancement ratio decreases with increasing particle LET. Nevertheless, current clinical practice does not yet fully benefit from the use of carbon ions to tackle hypoxia. Here, we provide an overview of the existing experimental and clinical evidence supporting the efficacy of C-ion radiotherapy in overcoming hypoxia-induced radioresistance, followed by a discussion of the strategies proposed to enhance it, including different approaches to maximize LET in the tumors.
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Affiliation(s)
- Olga Sokol
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforchung, Planckstraße 1, 64291 Darmstadt, Germany;
| | - Marco Durante
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforchung, Planckstraße 1, 64291 Darmstadt, Germany;
- Institute for Condensed Matter Physics, Technische Universität Darmstadt, Hochschulstraße 8, 64289 Darmstadt, Germany
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7
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The 'stealth-bomber' paradigm for deciphering the tumour response to carbon-ion irradiation. Br J Cancer 2023; 128:1429-1438. [PMID: 36639527 PMCID: PMC10070470 DOI: 10.1038/s41416-022-02117-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 12/01/2022] [Accepted: 12/08/2022] [Indexed: 01/14/2023] Open
Abstract
Numerous studies have demonstrated the higher biological efficacy of carbon-ion irradiation (C-ions) and their ballistic precision compared with photons. At the nanometre scale, the reactive oxygen species (ROS) produced by radiation and responsible for the indirect effects are differentially distributed according to the type of radiation. Photon irradiation induces a homogeneous ROS distribution, whereas ROS remain condensed in clusters in the C-ions tracks. Based on this linear energy transfer-dependent differential nanometric ROS distribution, we propose that the higher biological efficacy and specificities of the molecular response to C-ions rely on a 'stealth-bomber' effect. When biological targets are on the trajectories of the particles, the clustered radicals in the tracks are responsible for a 'bomber' effect. Furthermore, the low proportion of ROS outside the tracks is not able to trigger the cellular mechanisms of defence and proliferation. The ability of C-ions to deceive the cellular defence of the cancer cells is then categorised as a 'stealth' effect. This review aims to classify the biological arguments supporting the paradigm of the 'stealth-bomber' as responsible for the biological superiority of C-ions compared with photons. It also explains how and why C-ions will always be more efficient for treating patients with radioresistant cancers than conventional radiotherapy.
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8
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Yogo K, Murayama C, Hirayama R, Matsumoto KI, Nakanishi I, Ishiyama H, Yasuda H. Protective Effects of Amino Acids on Plasmid DNA Damage Induced by Therapeutic Carbon Ions. Radiat Res 2021; 196:197-203. [PMID: 34043797 DOI: 10.1667/rade-21-00033.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Accepted: 05/06/2021] [Indexed: 11/03/2022]
Abstract
Radioprotectors with few side effects are useful for carbon-ion therapy, which directly induces clustering damage in DNA. With the aim of finding the most effective radioprotector, we investigated the effects of selected amino acids which might have chemical DNA-repair functions against therapeutic carbon ions. In the current study, we employed five amino acids: tryptophan (Trp), cysteine (Cys), methionine (Met), valine (Val) and alanine (Ala). Samples of supercoiled pBR322 plasmid DNA with a 17 mM amino acid were prepared in TE buffer (10 mM Tris, 1 mM ethylenediaminetetraacetic acid, pH 7.5). Phosphate buffered saline (PBS) was also used in assays of the 0.17 mM amino acid. The samples were irradiated with carbon-ion beams (290 MeV/u) on 6 cm spread-out Bragg peak at the National Institute of Radiological Sciences-Heavy Ion Medical Accelerator in Chiba, Japan. Breaks in the DNA were detected as changes in the plasmids and quantified by subsequent electrophoresis on agarose gels. DNA damage yields and protection factors for each amino acid were calculated as ratios relative to reagent-free controls. Trp and Cys showed radioprotective effects against plasmid DNA damage induced by carbon-ion beam, both in PBS and TE buffer, comparable to those of Met. The double-strand break (DSB) yields and protective effects of Trp were comparable to those of Cys. The yields of both single-strand breaks and DSBs correlated with the scavenging capacity of hydroxyl radicals (rate constant for scavenging hydroxyl radicals multiplied by the amino acid concentration) in bulk solution. These data indicate that the radioprotective effects of amino acids against plasmid DNA damage induced by carbon ions could be explained primarily by the scavenging capacity of hydroxyl radicals. These findings suggest that some amino acids, such as Trp, Cys and Met, have good potential as radioprotectors for preventing DNA damage in normal tissues in carbon-ion therapy.
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Affiliation(s)
- Katsunori Yogo
- Graduate School of Medicine, Nagoya University, Nagoya, Japan
| | | | - Ryoichi Hirayama
- Quantum Life and Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Ken-Ichiro Matsumoto
- Quantum Life and Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Ikuo Nakanishi
- Quantum Life and Medical Science Directorate, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
| | - Hiromichi Ishiyama
- Graduate School of Medical Science, Kitasato University, Kanagawa, Japan
| | - Hiroshi Yasuda
- Department of Radiation Biophysics, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima, Japan
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9
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Kalholm F, Grzanka L, Traneus E, Bassler N. A systematic review on the usage of averaged LET in radiation biology for particle therapy. Radiother Oncol 2021; 161:211-221. [PMID: 33894298 DOI: 10.1016/j.radonc.2021.04.007] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2020] [Revised: 04/06/2021] [Accepted: 04/08/2021] [Indexed: 12/20/2022]
Abstract
Linear Energy Transfer (LET) is widely used to express the radiation quality of ion beams, when characterizing the biological effectiveness. However, averaged LET may be defined in multiple ways, and the chosen definition may impact the resulting reported value. We review averaged LET definitions found in the literature, and quantify which impact using these various definitions have for different reference setups. We recorded the averaged LET definitions used in 354 publications quantifying the relative biological effectiveness (RBE) of hadronic beams, and investigated how these various definitions impact the reported averaged LET using a Monte Carlo particle transport code. We find that the kind of averaged LET being applied is, generally, poorly defined. Some definitions of averaged LET may influence the reported averaged LET values up to an order of magnitude. For publications involving protons, most applied dose averaged LET when reporting RBE. The absence of what target medium is used and what secondary particles are included further contributes to an ill-defined averaged LET. We also found evidence of inconsistent usage of averaged LET definitions when deriving LET-based RBE models. To conclude, due to commonly ill-defined averaged LET and to the inherent problems of LET-based RBE models, averaged LET may only be used as a coarse indicator of radiation quality. We propose a more rigorous way of reporting LET values, and suggest that ideally the entire particle fluence spectra should be recorded and provided for future RBE studies, from which any type of averaged LET (or other quantities) may be inferred.
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Affiliation(s)
- Fredrik Kalholm
- Medical Radiation Physics, Dept. of Physics, Stockholm University, Stockholm, Sweden; Department of Oncology and Pathology, Medical Radiation Physics, Karolinska Institutet, Stockholm, Sweden
| | - Leszek Grzanka
- Institute of Nuclear Physics Polish Academy of Sciences, Krakow, Poland
| | | | - Niels Bassler
- Medical Radiation Physics, Dept. of Physics, Stockholm University, Stockholm, Sweden; Department of Oncology and Pathology, Medical Radiation Physics, Karolinska Institutet, Stockholm, Sweden; Department of Experimental Clinical Oncology, Aarhus University Hospital, Aarhus, Denmark; Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark; Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
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10
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Bendinger AL, Peschke P, Peter J, Debus J, Karger CP, Glowa C. High Doses of Photons and Carbon Ions Comparably Increase Vascular Permeability in R3327-HI Prostate Tumors: A Dynamic Contrast-Enhanced MRI Study. Radiat Res 2020; 194:465-475. [PMID: 33045073 DOI: 10.1667/rade-20-00112.1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 09/04/2020] [Indexed: 11/03/2022]
Abstract
Carbon- (12C-) ion radiotherapy exhibits enhanced biological effectiveness compared to photon radiotherapy, however, the contribution of its interaction with the vasculature remains debatable. The effect of high-dose 12C-ion and photon irradiation on vascular permeability in moderately differentiated rat prostate tumors was compared using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). Syngeneic R3327-HI rat prostate tumors were irradiated with a single dose of either 18 or 37 Gy 12C ions, or 37 or 75 Gy 6-MV photons (sub-curative and curative dose levels, respectively). DCE-MRI was performed one day prior to and 3, 7, 14 and 21 days postirradiation. Voxel-based tumor concentration-time curves were clustered based on their curve shape and treatment response was assessed as the longitudinal changes in the relative abundance per cluster. Radiation-induced vascular damage and increased permeability occurred at day 7 postirradiation for all treatment groups except for the 75 Gy photon-irradiated group, where the onset of vascular damage was delayed until day 14. No differences between irradiation modalities were found. Therefore, early vascular damage cannot explain the higher effectiveness of 12C ions relative to photons in terms of local tumor control for this moderately differentiated prostate tumor and the applied single high doses.
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Affiliation(s)
- Alina L Bendinger
- Department of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Faculty of Biosciences, University of Heidelberg, Heidelberg, Germany
| | - Peter Peschke
- Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Jörg Peter
- Department of Medical Physics in Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Jürgen Debus
- Clinical Cooperation Unit, Radiation Therapy, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Department of Radiation Oncology and Radiotherapy, University Hospital Heidelberg, Heidelberg, Germany
| | - Christian P Karger
- Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Christin Glowa
- Heidelberg Institute for Radiation Oncology (HIRO) and National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,Department of Radiation Oncology and Radiotherapy, University Hospital Heidelberg, Heidelberg, Germany
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11
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Tinganelli W, Durante M. Carbon Ion Radiobiology. Cancers (Basel) 2020; 12:E3022. [PMID: 33080914 PMCID: PMC7603235 DOI: 10.3390/cancers12103022] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2020] [Revised: 10/12/2020] [Accepted: 10/14/2020] [Indexed: 12/15/2022] Open
Abstract
Radiotherapy using accelerated charged particles is rapidly growing worldwide. About 85% of the cancer patients receiving particle therapy are irradiated with protons, which have physical advantages compared to X-rays but a similar biological response. In addition to the ballistic advantages, heavy ions present specific radiobiological features that can make them attractive for treating radioresistant, hypoxic tumors. An ideal heavy ion should have lower toxicity in the entrance channel (normal tissue) and be exquisitely effective in the target region (tumor). Carbon ions have been chosen because they represent the best combination in this direction. Normal tissue toxicities and second cancer risk are similar to those observed in conventional radiotherapy. In the target region, they have increased relative biological effectiveness and a reduced oxygen enhancement ratio compared to X-rays. Some radiobiological properties of densely ionizing carbon ions are so distinct from X-rays and protons that they can be considered as a different "drug" in oncology, and may elicit favorable responses such as an increased immune response and reduced angiogenesis and metastatic potential. The radiobiological properties of carbon ions should guide patient selection and treatment protocols to achieve optimal clinical results.
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Affiliation(s)
- Walter Tinganelli
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforchung, Planckstraße 1, 64291 Darmstadt, Germany;
| | - Marco Durante
- Biophysics Department, GSI Helmholtzzentrum für Schwerionenforchung, Planckstraße 1, 64291 Darmstadt, Germany;
- Institut für Festkörperphysik, Technische Universität Darmstadt, Hochschulstraße 8, 64289 Darmstadt, Germany
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12
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Yogo K, Murayama C, Fujisawa Y, Maeyama T, Hirayama R, Ogawa Y, Matsumoto KI, Nakanishi I, Yasuda H, Ishiyama H, Hayakawa K. Potential Mechanisms for Protective Effect of D-Methionine on Plasmid DNA Damage Induced by Therapeutic Carbon Ions. Radiat Res 2020; 193:513-519. [PMID: 32216711 DOI: 10.1667/rr15502.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 02/28/2020] [Indexed: 11/03/2022]
Abstract
D-methionine (D-met), a dextrorotatory isoform of the amino acid L-methionine (L-met), can prevent oral mucositis and salivary hypofunction in mice exposed to radiation. However, the mechanism of its radioprotection is unclear, especially with regard to the stereospecific functions of D-met. Radiation is known to cause injury to normal tissue by triggering DNA damage in cells. Thus, in this study we sought to determine whether the chirality of D-/L-met affects radiation-induced events at the DNA level. We selected plasmid DNA assays to examine this effect in vitro, since these assays are highly sensitive and allow easy detection of DNA damage. Samples of supercoiled pBR322 plasmid DNA mixed with D-met, L-met or dimethylsulfoxide (DMSO) were prepared and irradiated with a Bragg peak beam of carbon ions (∼290 MeV/u) with a 6-cm spread. DNA strand breaks were indicated by the change in the form of the plasmid and were subsequently quantified using agarose gel electrophoresis. We found that D-met yielded approximately equivalent protection from carbon-ion-induced DNA damage as DMSO. Thus, we propose that the protective functions of methionine against plasmid DNA damage could be explained by the same mechanism as that for DMSO, namely, hydroxyl radical scavenging. This stereospecific radioprotective mechanism occurred at a level other than the DNA level. There was no significant difference between the radioprotective effect of D-met and L-met on DNA.
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Affiliation(s)
- Katsunori Yogo
- Graduate School of Medicine, Nagoya University, Aichi 461-8673, Japan
| | - Chieko Murayama
- Tokai University School of Medicine, Kanagawa 259-1193, Japan
| | - Yoshiki Fujisawa
- Graduate School of Medical Science, Kitasato University, Kanagawa 252-0373, Japan
| | - Takuya Maeyama
- Graduate School of Science, Kitasato University, Kanagawa 252-0373, Japan
| | - Ryoichi Hirayama
- National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba 263-8555, Japan
| | - Yukihiro Ogawa
- National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba 263-8555, Japan
| | - Ken-Ichiro Matsumoto
- National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba 263-8555, Japan
| | - Ikuo Nakanishi
- National Institute of Radiological Sciences (NIRS), National Institutes for Quantum and Radiological Science and Technology (QST), Chiba 263-8555, Japan
| | - Hiroshi Yasuda
- Department of Radiation Biophysics, Research Institute for Radiation Biology and Medicine, Hiroshima University, Hiroshima 734-8553, Japan
| | - Hiromichi Ishiyama
- Graduate School of Medical Science, Kitasato University, Kanagawa 252-0373, Japan
| | - Kazushige Hayakawa
- Graduate School of Medical Science, Kitasato University, Kanagawa 252-0373, Japan
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13
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Sato K, Shimokawa T, Imai T. Difference in Acquired Radioresistance Induction Between Repeated Photon and Particle Irradiation. Front Oncol 2019; 9:1213. [PMID: 31799186 PMCID: PMC6863406 DOI: 10.3389/fonc.2019.01213] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Accepted: 10/23/2019] [Indexed: 12/21/2022] Open
Abstract
In recent years, advanced radiation therapy techniques, including stereotactic body radiotherapy and carbon–ion radiotherapy, have progressed to such an extent that certain types of cancer can be treated with radiotherapy alone. The therapeutic outcomes are particularly promising for early stage lung cancer, with results matching those of surgical resection. Nevertheless, patients may still experience local tumor recurrence, which might be exacerbated by the acquisition of radioresistance after primary radiotherapy. Notwithstanding the risk of tumors acquiring radioresistance, secondary radiotherapy is increasingly used to treat recurrent tumors. In this context, it appears essential to comprehend the radiobiological effects of repeated photon and particle irradiation and their underlying cellular and molecular mechanisms in order to achieve the most favorable therapeutic outcome. However, to date, the mechanisms of acquisition of radioresistance in cancer cells have mainly been studied after repeated in vitro X-ray irradiation. By contrast, other critical aspects of radioresistance remain mostly unexplored, including the response to carbon-ion irradiation of X-ray radioresistant cancer cells, the mechanisms of acquisition of carbon-ion resistance, and the consequences of repeated in vivo X-ray or carbon-ion irradiation. In this review, we discuss the underlying mechanisms of acquisition of X-ray and carbon-ion resistance in cancer cells, as well as the phenotypic differences between X-ray and carbon-ion-resistant cancer cells, the biological implications of repeated in vivo X-ray or carbon-ion irradiation, and the main open questions in the field.
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Affiliation(s)
- Katsutoshi Sato
- Division of Hematology and Medical Oncology, Icahn School of Medicine at Mount Sinai, The Tisch Cancer Institute, New York, NY, United States
| | - Takashi Shimokawa
- Department of Accelerator and Medical Physics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Sciences and Technology, Chiba, Japan
| | - Takashi Imai
- Medical Databank, Department of Radiation Medicine, QST Hospital, National Institutes for Quantum and Radiological Science and Technology, Chiba, Japan
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14
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Fossati P, Matsufuji N, Kamada T, Karger CP. Radiobiological issues in prospective carbon ion therapy trials. Med Phys 2018; 45:e1096-e1110. [PMID: 30421806 DOI: 10.1002/mp.12506] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 05/29/2017] [Accepted: 07/26/2017] [Indexed: 12/15/2022] Open
Abstract
Carbon ion radiotherapy (CIRT) is developing toward a versatile tool in radiotherapy; however, the increased relative biological effectiveness (RBE) of carbon ions in tumors and normal tissues with respect to photon irradiation has to be considered by mathematical models in treatment planning. As a consequence, dose prescription and definition of dose constraints are performed in terms of RBE weighted rather than absorbed dose. The RBE is a complex quantity, which depends on physical variables, such as dose and beam quality as well as on normal tissue- or tumor-specific factors. At present, three RBE models are employed in CIRT: (a) the mixed-beam model, (b) the Microdosimetric Kinetic Model (MKM), and (c) the local effect model. While the LEM is used in Europe, the other two models are employed in Japan, and unfortunately, the concepts of how the nominal RBE-weighted dose is determined and prescribed differ significantly between the European and Japanese centers complicating the comparison, transfer, and reproduction of clinical results. This has severe impact on the way treatments should be prescribed, recorded, and reported. This contribution reviews the concept of the clinical application of the different RBE models and the ongoing clinical CIRT trials in Japan and Europe. Limitations of the RBE models and the resulting radiobiological issues in clinical CIRT trials are discussed in the context of current clinical evidence and future challenges.
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Affiliation(s)
- Piero Fossati
- Fondazione CNAO (Centro Nazionale di Adroterapia Oncologica), Pavia, Italy.,European Institute of Oncology, Milano, Italy
| | | | - Tadashi Kamada
- National Institute of Radiological Sciences, Chiba, Japan
| | - Christian P Karger
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany
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15
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Ueno M, Nakanishi I, Matsumoto KI. A New Approach for Quantifying Radio-Biological Effects Using the Time Course of Mouse Leg Contracture. Biol Pharm Bull 2018; 41:368-373. [PMID: 29491213 DOI: 10.1248/bpb.b17-00689] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A digitization approach to the time course of radiation-induced mouse leg contracture was proposed for quantifying the radiation effect on an individual living mouse. The shortening of the mouse leg length can be easily measured with a caliper/ruler to offer a very simple digitalized index of the radiation effect. Left hind legs of mice were irradiated with single dose of 32 Gy of 290 MeV carbon-ion beam using 0, 50, or 117 mm binary filter (BF). The right legs were used as a control. The lengths of both hind legs of the mice were measured using a digital caliper before irradiation and every week after irradiation. The degree of leg contracture, ΔSt, at the time point t was estimated by subtraction of the left irradiated leg length from the right control leg length. Equation was fitted on the daily time course of ΔSt, and two parameters, ΔSmax and Ts, were estimated. ΔSt=ΔSmax×(1-exp(t/Ts)), where ΔSmax is the maximum degree of leg contracture, and Ts is time of leg contracture. The effect of carbon-ion irradiation on a living mouse was quantified by ΔSmax and Ts of the leg contracture, and then compared to that of X-rays. By 32 Gy irradiation, ΔSmax was largest for the BF117 experiment, followed by X-ray~BF50>BF0. Ts was shortest for the BF50 experiment, while other irradiation conditions give similar Ts. A logarithmic function was successfully repurposed for the evaluation of radio-biological response.
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Affiliation(s)
- Megumi Ueno
- Quantitative RedOx Sensing Team, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology
| | - Ikuo Nakanishi
- Quantitative RedOx Sensing Team, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology
| | - Ken-Ichiro Matsumoto
- Quantitative RedOx Sensing Team, Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology
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16
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Matsumoto Y, Furusawa Y, Uzawa A, Hirayama R, Koike S, Ando K, Tsuboi K, Sakurai H. Antimetastatic Effects of Carbon-Ion Beams on Malignant Melanomas. Radiat Res 2018; 190:412-423. [DOI: 10.1667/rr15075.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Yoshitaka Matsumoto
- Radiation Oncology, Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, 305-8575, Japan
| | - Yoshiya Furusawa
- Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Akiko Uzawa
- Department of Charged Particle Therapy Research, Clinical Research Cluster, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Ryoichi Hirayama
- Department of Charged Particle Therapy Research, Clinical Research Cluster, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Sachiko Koike
- Department of Accelerator and Medical Physics, National Institute of Radiological Sciences, National Institutes for Quantum and Radiological Science and Technology, Chiba, 263-8555, Japan
| | - Koichi Ando
- Medicine & Biology Division, Heavy Ion Medical Center, Gunma University, Gunma, 371-8511, Japan
| | - Koji Tsuboi
- Radiation Oncology, Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, 305-8575, Japan
| | - Hideyuki Sakurai
- Radiation Oncology, Clinical Medicine, Faculty of Medicine, University of Tsukuba, Tsukuba, 305-8575, Japan
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17
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Sato K, Nitta N, Aoki I, Imai T, Shimokawa T. Repeated photon and C-ion irradiations in vivo have different impact on alteration of tumor characteristics. Sci Rep 2018; 8:1458. [PMID: 29362374 PMCID: PMC5780469 DOI: 10.1038/s41598-018-19422-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Accepted: 12/12/2017] [Indexed: 12/16/2022] Open
Abstract
Precise characterization of tumor recurrence and regrowth after radiotherapy are important for prognostic understanding of the therapeutic effect. Here, we established a novel in vivo mouse model for evaluating the characteristics of regrown tumor after repeated photon and carbon ion (C-ion) irradiations. The results showed that tumor growth rate, lung metastasis, shortening of the survival of the tumor-bearing mice, and tumor microvessel formation were promoted 2- to 3-fold, and expression of angiogenic and metastatic genes increased 1.5- to 15-fold in regrown tumors after repeated photon irradiations, whereas repeated C-ion irradiations did not alter these characteristics. Interestingly, both repeated photon and C-ion irradiations did not generate radioresistance, which is generally acquired for in vitro treatment. Our results demonstrated that the repetition of photon, and not C-ion, irradiations in vivo alter the characteristics of the regrown tumor, making it more aggressive without acquisition of radioresistance.
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Affiliation(s)
- Katsutoshi Sato
- Cancer Metastasis Research Team, Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, QST, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
- Clinical Genetic Oncology, Cancer Institute Hospital, Japanese Foundation for Cancer Research, 3-8-31 Koto-Ku, Tokyo, 135-8550, Japan
| | - Nobuhiro Nitta
- Department of Molecular Imaging and Theranostics, and Group of Quantum-state Controlled MRI, National Institute of Radiological Sciences, QST, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - Ichio Aoki
- Department of Molecular Imaging and Theranostics, and Group of Quantum-state Controlled MRI, National Institute of Radiological Sciences, QST, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - Takashi Imai
- National Institute of Radiological Sciences, QST, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan
| | - Takashi Shimokawa
- Cancer Metastasis Research Team, Advanced Radiation Biology Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences, QST, 4-9-1 Anagawa, Inage-ku, Chiba, 263-8555, Japan.
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18
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Abstract
Carbon ion therapy is a promising evolving modality in radiotherapy to treat tumors that are radioresistant against photon treatments. As carbon ions are more effective in normal and tumor tissue, the relative biological effectiveness (RBE) has to be calculated by bio-mathematical models and has to be considered in the dose prescription. This review (i) introduces the concept of the RBE and its most important determinants, (ii) describes the physical and biological causes of the increased RBE for carbon ions, (iii) summarizes available RBE measurements in vitro and in vivo, and (iv) describes the concepts of the clinically applied RBE models (mixed beam model, local effect model, and microdosimetric-kinetic model), and (v) the way they are introduced into clinical application as well as (vi) their status of experimental and clinical validation, and finally (vii) summarizes the current status of the use of the RBE concept in carbon ion therapy and points out clinically relevant conclusions as well as open questions. The RBE concept has proven to be a valuable concept for dose prescription in carbon ion radiotherapy, however, different centers use different RBE models and therefore care has to be taken when transferring results from one center to another. Experimental studies significantly improve the understanding of the dependencies and limitations of RBE models in clinical application. For the future, further studies investigating quantitatively the differential effects between normal tissues and tumors are needed accompanied by clinical studies on effectiveness and toxicity.
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Affiliation(s)
- Christian P Karger
- Department of Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120 Heidelberg, Germany. National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany. Author to whom any correspondence should be addressed
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19
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Glowa C, Peschke P, Brons S, Neels OC, Kopka K, Debus J, Karger CP. Carbon ion radiotherapy: impact of tumor differentiation on local control in experimental prostate carcinomas. Radiat Oncol 2017; 12:174. [PMID: 29121984 PMCID: PMC5679331 DOI: 10.1186/s13014-017-0914-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/27/2017] [Indexed: 11/30/2022] Open
Abstract
Background To summarize the research activities of the “clinical research group heavy ion therapy”, funded by the German Research Foundation (DFG, KFO 214), on the impact of intrinsic tumor characteristics (grading, hypoxia) on local tumor control after carbon (12C-) ion- and photon irradiations. Methods Three sublines of syngeneic rat prostate tumors (R3327) with various differentiation levels (highly (-H), moderately (-HI) or anaplastic (-AT1), (diameter 10 mm) were irradiated with 1, 2 and 6 fractions of either 12C-ions or 6 MV photons using increasing dose levels. Primary endpoint was local tumor control at 300 days. The relative biological effectiveness (RBE) of 12C-ions was calculated from TCD50-values (dose at 50% tumor control probability) of photons and 12C-ions and correlated with intrinsic tumor parameters. For the HI-subline, larger tumors (diameter 18 mm) were irradiated with either carbon ions, oxygen ions or photons under ambient as well as hypoxic conditions to determine the variability of the RBE under different oxygenation levels. In addition, imaging, histology and molecular analyses were performed to decipher the underlying mechanisms. Results Experimental results revealed (i) a smaller variation of the TCD50-values between the three tumor sublines for 12C-ions (23.6 - 32.9 Gy) than for photons (38.2 - 75.7 Gy), (ii) steeper dose-response curves for 12C-ions, and (iii) an RBE that increased with tumor grading (1.62 ± 0.11 (H) vs 2.08 ± 0.13 (HI) vs 2.30 ± 0.08 (AT1)). Large HI-tumors resulted in a marked increase of TCD50, which was increased further by 15% under hypoxic relative to oxic conditions. Noninvasive imaging, histology and molecular analyses identified hypoxia as an important radioresistance factor in photon therapy. Conclusions The dose-response studies revealed a higher efficacy of 12C-ions relative to photon therapy in the investigated syngeneic tumor model. Hypoxia turned out to be at least one important radioresistance factor, which can be partly overridden by high-LET ion beams. This might be used to increase treatment effectiveness also in patients. The results of this project served as a starting point for several ongoing research projects.
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Affiliation(s)
- Christin Glowa
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany. .,Department of Medical Physics in Radiation Oncology (E040), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany. .,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.
| | - Peter Peschke
- Department of Medical Physics in Radiation Oncology (E040), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Stephan Brons
- National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,Heidelberg Ion Beam Therapy Center (HIT), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany
| | - Oliver C Neels
- Division of Radiopharmaceutical Chemistry, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany.,German Cancer Consortium (DKTK), Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Klaus Kopka
- Division of Radiopharmaceutical Chemistry, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany.,German Cancer Consortium (DKTK), Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Jürgen Debus
- Department of Radiation Oncology, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120, Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
| | - Christian P Karger
- Department of Medical Physics in Radiation Oncology (E040), German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69120, Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Im Neuenheimer Feld 400, 69120, Heidelberg, Germany
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20
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Sunada S, Hirakawa H, Fujimori A, Uesaka M, Okayasu R. Oxygen Enhancement Ratio in Radiation-Induced Initial DSBs by an Optimized Flow Cytometry-based Gamma-H2AX Analysis in A549 Human Cancer Cells. Radiat Res 2017; 188:591-594. [DOI: 10.1667/rr14824.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
- Shigeaki Sunada
- Department of Nuclear Engineering and Management, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8656, Japan
| | - Hirokazu Hirakawa
- Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Inage-ku, Chiba, 263-8555, Japan
| | - Akira Fujimori
- Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Inage-ku, Chiba, 263-8555, Japan
| | - Mitsuru Uesaka
- Department of Nuclear Engineering and Management, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-8656, Japan
| | - Ryuichi Okayasu
- Department of Basic Medical Sciences for Radiation Damages, National Institute of Radiological Sciences, Inage-ku, Chiba, 263-8555, Japan
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21
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Shiba S, Wakatsuki M, Kato S, Ohno T, Okonogi N, Karasawa K, Kiyohara H, Tsujii H, Nakano T, Kamada T, Shozu M. Carbon-ion radiotherapy for locally advanced cervical cancer with bladder invasion. JOURNAL OF RADIATION RESEARCH 2016; 57:684-690. [PMID: 27422932 PMCID: PMC5137292 DOI: 10.1093/jrr/rrw070] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 02/28/2016] [Accepted: 05/18/2016] [Indexed: 06/06/2023]
Abstract
The purpose of this study was to evaluate the efficacy and toxicities of carbon-ion radiotherapy (C-ion RT) for locally advanced cervical cancer with bladder invasion by a subset analysis of pooled data from eight prospective clinical trials at the National Institute of Radiological Sciences. Between June 1995 and January 2014, 29 patients with locally advanced cervical cancer with bladder invasion were identified. The median age was 56 years old (range 31-79 years old). The median tumor size at diagnosis on magnetic resonance imaging was 6.7 cm (range 3.5-11.0 cm). Histologically, 20 patients had squamous cell carcinoma and 9 had adenocarcinoma. C-ion RT was performed as a dose-escalation study in the initial trials. All patients received prophylactic whole-pelvic or extended-field irradiation and local boost. The total dose to the cervical tumor was 52.8-74.4 Gy (relative biological effectiveness) in 20 or 24 fractions. Weekly cisplatin (40 mg/m2/week, five cycles) was concurrently given to four patients. The median follow-up of all patients was 28.6 months (range 8.8-238.6 months). Grade 2 or higher late complications in the bladder were observed in eight patients, with seven developing vesicovaginal fistula. Six patients had Grade 2 or higher complications in the rectosigmoid colon. The 3-year overall survival rate was 47%, the 3-year local control rate was 66%, and the 3-year disease-free survival rate was 28%. In this study, C-ion RT showed favorable local control with reasonable toxicities, but the results were still unsatisfactory. We have the expectation of improvement of therapeutic effects by using C-ion RT with concurrent chemotherapy.
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Affiliation(s)
- Shintaro Shiba
- Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
- National Institutes for Quantum and Radiological Science and Technology, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-city, Chiba 263-8555, Japan
| | - Masaru Wakatsuki
- National Institutes for Quantum and Radiological Science and Technology, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-city, Chiba 263-8555, Japan
- Department of Radiology, Jichi Medical University, 3311-1, Yakushiji, Simotsuke-city, Tochigi 329-0498, Japan
| | - Shingo Kato
- Department of Radiation Oncology, Saitama Medical University International Medical Center, 1397-1 Yamane, Hidaka, Saitama 350-1298, Japan
| | - Tatsuya Ohno
- Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Noriyuki Okonogi
- National Institutes for Quantum and Radiological Science and Technology, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-city, Chiba 263-8555, Japan
| | - Kumiko Karasawa
- Department of Radiation Oncology, Tokyo Women's Medical University, School of Medicine, 8-1 Kawada-cho, Shinjuku-ku, Tokyo 162-8666, Japan
| | - Hiroki Kiyohara
- Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Hirohiko Tsujii
- National Institutes for Quantum and Radiological Science and Technology, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-city, Chiba 263-8555, Japan
| | - Takashi Nakano
- Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Tadashi Kamada
- National Institutes for Quantum and Radiological Science and Technology, National Institute of Radiological Sciences, 4-9-1 Anagawa, Inage-ku, Chiba-city, Chiba 263-8555, Japan
| | - Makio Shozu
- Department of Reproductive Medicine, Graduate School of Medicine, Chiba University, 1-8-1 Inohara Chuo-ku, Chiba 260-8670, Japan
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Hirayama R, Uzawa A, Obara M, Takase N, Koda K, Ozaki M, Noguchi M, Matsumoto Y, Li H, Yamashita K, Koike S, Ando K, Shirai T, Matsufuji N, Furusawa Y. Determination of the relative biological effectiveness and oxygen enhancement ratio for micronuclei formation using high-LET radiation in solid tumor cells: An in vitro and in vivo study. MUTATION RESEARCH-GENETIC TOXICOLOGY AND ENVIRONMENTAL MUTAGENESIS 2015; 793:41-7. [PMID: 26520371 DOI: 10.1016/j.mrgentox.2015.08.003] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Accepted: 08/10/2015] [Indexed: 11/27/2022]
Abstract
We determined the relative biological effectiveness (RBE) and oxygen enhancement ratio (OER) of micronuclei (MN) formation in clamped (hypoxic) and non-clamped (normoxic) solid tumors in mice legs following exposure to X-rays and heavy ions. Single-cell suspensions (aerobic) of non-irradiated tumors were prepared in parallel and used directly to determine the radiation response for aerobic cells. Squamous cell carcinoma (SCCVII) cells were transplanted into the right hind legs of syngeneic C3H/He male mice. Irradiation doses with either X-rays or heavy ions at a dose-averaged LET (linear energy transfer) of 14-192keV/μm were delivered to 5-mm diameter tumors and aerobic single-cells in sample-tubes. After irradiation, the tumors were excised and trypsinized to observe MN in single-cells. The single-cell suspensions were used for MN formation assays. The RBE values increased with increasing LET. The maximum RBE values for the three different oxygen conditions; hypoxic tumor, normoxic tumor, and aerobic cells, were 8.18, 5.30, and 3.76 at an LET of 192keV/μm, respectively. After X-irradiation, the OERh/n values (hypoxic tumor/normoxic tumor) were lower than the OERh/a (hypoxic tumor/aerobic cells), and were 1.73 and 2.58, respectively. We found that the OER for the in vivo studies were smaller in comparison to that for the in vitro studies. Both of the OER values at 192keV/μm were small in comparison to those of the X-ray irradiated samples. The OERh/n and OERh/a values at 192keV/μm were 1.12 and 1.19, respectively. Our results suggest that high LET radiation has a large biological effect even if a solid tumor includes substantial numbers of hypoxic cells. To conclude, we found that the RBE values under each oxygen state for non-MN fraction increased with increasing LET and that the OER values for both tumors in vivo and cells in vitro decreased with increasing LET.
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Affiliation(s)
- Ryoichi Hirayama
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan.
| | - Akiko Uzawa
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Maki Obara
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Nobuhiro Takase
- School of Engineering, Tokai University, 1117 Kitakaname, Hiratsuka-shi, Kanagawa 259-1292, Japan
| | - Kana Koda
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Masakuni Ozaki
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Miho Noguchi
- Advanced Science Research Center, Japan Atomic Energy Agency (JAEA), 2-4 Shirakata-Shirane, Tokai-mura, Naka-gun, Ibaraki 319-1195, Japan
| | - Yoshitaka Matsumoto
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Huizi Li
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Kei Yamashita
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Sachiko Koike
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Koichi Ando
- Heavy Ion Medical Center, Gunma University, 3-39-22 Showa-machi, Maebashi-shi, Gunma 371-8511, Japan
| | - Toshiyuki Shirai
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Naruhiro Matsufuji
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
| | - Yoshiya Furusawa
- Medical Physics Research Program, Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-8555, Japan
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23
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Nakano T, Mitsusada Y, Salem AMH, Shoulkamy MI, Sugimoto T, Hirayama R, Uzawa A, Furusawa Y, Ide H. Induction of DNA-protein cross-links by ionizing radiation and their elimination from the genome. Mutat Res 2015; 771:45-50. [PMID: 25771979 DOI: 10.1016/j.mrfmmm.2014.12.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2014] [Revised: 12/04/2014] [Accepted: 12/16/2014] [Indexed: 06/04/2023]
Abstract
Ionizing radiation produces various types of DNA lesions, such as base damage, single-strand breaks, double-strand breaks (DSBs), and DNA-protein cross-links (DPCs). Of these, DSBs are the most critical lesions underlying the lethal effects of ionizing radiation. With DPCs, proteins covalently trapped in DNA constitute strong roadblocks to replication and transcription machineries, and hence can be lethal to cells. The formation of DPCs by ionizing radiation is promoted in the absence of oxygen, whereas that of DSBs is retarded. Accordingly, the contribution of DPCs to the lethal events in irradiated cells may not be negligible for hypoxic cells, such as those present in tumors. However, the role of DPCs in the lethal effects of ionizing radiation remains largely equivocal. In the present study, normoxic and hypoxic mouse tumors were irradiated with X-rays [low linear energy transfer (LET) radiation] and carbon (C)-ion beams (high LET radiation), and the resulting induction of DPCs and DSBs and their removal from the genome were analyzed. X-rays and C-ion beams produced more DPCs in hypoxic tumors than in normoxic tumors. Interestingly, the yield of DPCs was slightly but statistically significantly greater (1.3- to 1.5-fold) for C-ion beams than for X-rays. Both X-rays and C-ion beams generated two types of DPC that differed according to their rate of removal from the genome. This was also the case for DSBs. The half-lives of the rapidly removed components of DPCs and DSBs were similar (<1 h), but those of the slowly removed components of DPCs and DSBs were markedly different (3.9-5 h for DSBs versus 63-70 h for DPCs). The long half-life and abundance of the slowly removed DPCs render them persistent in DNA, which may impede DNA transactions and confer deleterious effects on cells in conjunction with DSBs.
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Affiliation(s)
- Toshiaki Nakano
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Yusuke Mitsusada
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Amir M H Salem
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan; Department of Pathology, Medical Research Division, National Research Centre, El-Bohouth St., Dokki, Giza 12311, Egypt
| | - Mahmoud I Shoulkamy
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan; Department of Zoology, Biological Science Building, Faculty of Science, Minia University, Minia 61519, Egypt
| | - Tatsuya Sugimoto
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan
| | - Ryoichi Hirayama
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), Chiba 263-8555, Japan
| | - Akiko Uzawa
- Research Center for Charged Particle Therapy, National Institute of Radiological Sciences (NIRS), Chiba 263-8555, Japan
| | - Yoshiya Furusawa
- Development and Support Center, National Institute of Radiological Sciences (NIRS), Chiba 263-8555, Japan
| | - Hiroshi Ide
- Department of Mathematical and Life Sciences, Graduate School of Science, Hiroshima University, Higashi-Hiroshima 739-8526, Japan.
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24
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Sato K, Imai T, Okayasu R, Shimokawa T. Heterochromatin domain number correlates with X-ray and carbon-ion radiation resistance in cancer cells. Radiat Res 2014; 182:408-19. [PMID: 25229975 DOI: 10.1667/rr13492.1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Although it is known that cancer cells can develop radiation resistance after repeated exposures to X rays, the underlying mechanisms and characteristics of this radiation-induced resistance of cancer cells are not well understood. Additionally, it is not known whether cells that develop X-ray resistance also would develop resistance to other types of radiation such as heavy-ions including carbon ions (C-ion). In this study, we established X-ray resistant cancer cell lines by delivering repeated exposures to X rays, and then assessed whether the cells were resistant to carbon ions. The mouse squamous cell carcinoma cell line, NR-S1, was X irradiated six times with 10 Gy, and the X-ray resistant cancer cells named X60 and ten subclones were established. Significant X-ray resistance was induced in four of the subclones (X60, X60-H2, X60-A3 and X60-B12). The X60 cells and all of the subclones were resistant to carbon ions. The correlation analysis between radioresistance and morphological characteristics of these cells showed that X-ray (R=0.74) and C-ion (R=0.79) resistance correlated strongly with the number of heterochromatin domains. Moreover, the numbers of γ-H2AX foci remaining in irradiated X60 cells and radioresistant subclones X60-A3 and X60-H2 were lower than in the NR-S1 cells after X-ray or C-ion irradiation, indicating that X60 cells and the radioresistant subclones rapidly repaired the DNA double-strand breaks compared with NR-S1 cells. Our findings suggest that the underlying causal mechanisms of X-ray and C-ion radiation resistance may overlap, and that an increase in heterochromatin domain number may be an indicator of X-ray and C-ion resistance.
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25
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Radiation oncology in vitro: trends to improve radiotherapy through molecular targets. BIOMED RESEARCH INTERNATIONAL 2014; 2014:461687. [PMID: 25302298 PMCID: PMC4180203 DOI: 10.1155/2014/461687] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/05/2014] [Accepted: 07/16/2014] [Indexed: 12/17/2022]
Abstract
Much has been investigated to improve the beneficial effects of radiotherapy especially in that case where radioresistant behavior is observed. Beyond simple identification of resistant phenotype the discovery and development of specific molecular targets have demonstrated therapeutic potential in cancer treatment including radiotherapy. Alterations on transduction signaling pathway related with MAPK cascade are the main axis in cancer cellular proliferation even as cell migration and invasiveness in irradiated tumor cell lines; then, for that reason, more studies are in course focusing on, among others, DNA damage enhancement, apoptosis stimulation, and growth factors receptor blockages, showing promising in vitro results highlighting molecular targets associated with ionizing radiation as a new radiotherapy strategy to improve clinical outcome. In this review we discuss some of the main molecular targets related with tumor cell proliferation and migration as well as their potential contributions to radiation oncology improvements.
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