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Nakamura S, Takemori M, Nakaichi T, Shuto Y, Kashihara T, Iijima K, Chiba T, Nakayama H, Urago Y, Nishina S, Kobayashi Y, Kishida H, Imamichi S, Takahashi K, Masutani M, Okamoto H, Nishio T, Itami J, Igaki H. A method for delivering the required neutron fluence in an accelerator-based boron neutron capture therapy system employing a lithium target. Sci Rep 2024; 14:11253. [PMID: 38755333 PMCID: PMC11099010 DOI: 10.1038/s41598-024-62060-9] [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: 12/31/2023] [Accepted: 05/13/2024] [Indexed: 05/18/2024] Open
Abstract
Accelerator-based boron neutron capture therapy (BNCT) systems employing a solid-state lithium target indicated the reduction of neutron flux over the lifetime of a target, and its reduction could represent the neutron flux model. This study proposes a novel compensatory approach for delivering the required neutron fluence and validates its clinical applicability. The proposed approach relies on the neutron flux model and the cumulative sum of real-time measurements of proton charges. The accuracy of delivering the required neutron fluence for BNCT using the proposed approach was examined in five Li targets. With the proposed approach, the required neutron fluence could be delivered within 3.0%, and within 1.0% in most cases. However, those without using the proposed approach exceeded 3.0% in some cases. The proposed approach can consider the neutron flux reduction adequately and decrease the effect of uncertainty in neutron measurements. Therefore, the proposed approach can improve the accuracy of delivering the required fluence for BNCT even if a neutron flux reduction is expected during treatment and over the lifetime of the Li target. Additionally, by adequately revising the approach, it may apply to other type of BNCT systems employing a Li target, furthering research in this direction.
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Affiliation(s)
- Satoshi Nakamura
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
- Division of Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan.
- Medical Physics Laboratory, Division of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita City, Osaka, 565-0871, Japan.
| | - Mihiro Takemori
- Division of Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Tetsu Nakaichi
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Division of Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Yasunori Shuto
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Comprehensive Oncology, Nagasaki University Graduate School of Biomedical Sciences, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiological Technology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Tairo Kashihara
- Division of Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Kotaro Iijima
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Takahito Chiba
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, 7-2-10 Hitashi-ogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - Hiroki Nakayama
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Yuka Urago
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, 7-2-10 Hitashi-ogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - Shuka Nishina
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiological Sciences, Komazawa University, 1-23-1 Komazawa, Setagaya-ku, Tokyo, 154-8525, Japan
| | - Yuta Kobayashi
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Hironori Kishida
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Shoji Imamichi
- Division of Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Central Radioisotope Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Molecular and Genomic Biomedicine, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto 1-12-4, Nagasaki, 852-8523, Japan
| | - Kana Takahashi
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Mitsuko Masutani
- Division of Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Central Radioisotope Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Molecular and Genomic Biomedicine, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto 1-12-4, Nagasaki, 852-8523, Japan
| | - Hiroyuki Okamoto
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Teiji Nishio
- Medical Physics Laboratory, Division of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita City, Osaka, 565-0871, Japan
| | - Jun Itami
- Radiation Therapy, Shin-Matsudo Central General Hospital, 1-380 Shin-Matsudo, Matsudo City, Chiba, 270-0034, Japan
| | - Hiroshi Igaki
- Division of Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research and Clinical Trial Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Comprehensive Oncology, Nagasaki University Graduate School of Biomedical Sciences, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
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Nakamura S, Imamichi S, Shimada K, Takemori M, Kanai Y, Iijima K, Chiba T, Nakayama H, Nakaichi T, Mikasa S, Urago Y, Kashihara T, Takahashi K, Nishio T, Okamoto H, Itami J, Ishiai M, Suzuki M, Igaki H, Masutani M. Relative biological effectiveness for epithermal neutron beam contaminated with fast neutrons in the linear accelerator-based boron neutron capture therapy system coupled to a solid-state lithium target. JOURNAL OF RADIATION RESEARCH 2023:7192974. [PMID: 37295954 PMCID: PMC10354855 DOI: 10.1093/jrr/rrad037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 01/30/2023] [Indexed: 06/12/2023]
Abstract
This study aimed to quantify the relative biological effectiveness (RBE) for epithermal neutron beam contaminated with fast neutrons in the accelerator-based boron neutron capture therapy (BNCT) system coupled to a solid-state lithium target. The experiments were performed in National Cancer Center Hospital (NCCH), Tokyo, Japan. Neutron irradiation with the system provided by Cancer Intelligence Care Systems (CICS), Inc. was performed. X-ray irradiation, which was assigned as the reference group, was also performed using a medical linear accelerator (LINAC) equipped in NCCH. The four cell lines (SAS, SCCVII, U87-MG and NB1RGB) were utilized to quantify RBE value for the neutron beam. Before both of those irradiations, all cells were collected and dispensed into vials. The doses of 10% cell surviving fraction (SF) (D10) were calculated by LQ model fitting. All cell experiments were conducted in triplicate at least. Because the system provides not only neutrons, but gamma-rays, the contribution from the gamma-rays to the survival fraction were subtracted in this study. D10 value of SAS, SCCVII, U87-MG and NB1RGB for the neutron beam was 4.26, 4.08, 5.81 and 2.72 Gy, respectively, while that acquired by the X-ray irradiation was 6.34, 7.21, 7.12 and 5.49 Gy, respectively. Comparison of both of the D10 values, RBE value of SAS, SCCVII, U87-MG and NB1RGB for the neutron beam was calculated as 1.7, 2.2, 1.3 and 2.5, respectively, and the average RBE value was 1.9. This study investigated RBE of the epithermal neutron beam contaminated with fast neutrons in the accelerator-based BNCT system coupled to a solid-state lithium target.
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Affiliation(s)
- Satoshi Nakamura
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Division of Boron Neutron Capture Therapy, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Medical Physics Laboratory, Division of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita city, Osaka, 565-0871, Japan
| | - Shoji Imamichi
- Division of Boron Neutron Capture Therapy, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Central Radioisotope Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Molecular and Genomic Biomedicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan
| | - Kenzi Shimada
- Cancer Intelligence Care Systems, Inc. 3-5-7 Ariake, Koto-ku, Tokyo, 135-0063, Japan
| | - Mihiro Takemori
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Division of Boron Neutron Capture Therapy, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiological Science, Graduate School of Human Health Sciences, 7-2-10 Higashi-ogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - Yui Kanai
- Division of Boron Neutron Capture Therapy, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Central Radioisotope Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Laboratory for Zero-Carbon Energy, Institute of Innovative Research, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo, 152-5880, Japan
| | - Kotaro Iijima
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Takahito Chiba
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiological Science, Graduate School of Human Health Sciences, 7-2-10 Higashi-ogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - Hiroki Nakayama
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiological Science, Graduate School of Human Health Sciences, 7-2-10 Higashi-ogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - Tetsu Nakaichi
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Division of Boron Neutron Capture Therapy, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Shohei Mikasa
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Yuka Urago
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiological Science, Graduate School of Human Health Sciences, 7-2-10 Higashi-ogu, Arakawa-ku, Tokyo, 116-8551, Japan
| | - Tairo Kashihara
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Kana Takahashi
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Teiji Nishio
- Medical Physics Laboratory, Division of Health Science, Graduate School of Medicine, Osaka University, 1-7 Yamadaoka, Suita city, Osaka, 565-0871, Japan
| | - Hiroyuki Okamoto
- Division of Radiation Safety and Quality Assurance, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Jun Itami
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Masamichi Ishiai
- Division of Boron Neutron Capture Therapy, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Central Radioisotope Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Minoru Suzuki
- Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2 Asashiro-Nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan
| | - Hiroshi Igaki
- Division of Boron Neutron Capture Therapy, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
| | - Mitsuko Masutani
- Division of Boron Neutron Capture Therapy, Exploratory Oncology Research & Clinical Trial Center, National Cancer Center, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Central Radioisotope Division, National Cancer Center Research Institute, 5-1-1 Tsukiji, Chuo-ku, Tokyo, 104-0045, Japan
- Department of Molecular and Genomic Biomedicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8588, Japan
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Neutron flux evaluation model provided in the accelerator-based boron neutron capture therapy system employing a solid-state lithium target. Sci Rep 2021; 11:8090. [PMID: 33850253 PMCID: PMC8044165 DOI: 10.1038/s41598-021-87627-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2020] [Accepted: 04/01/2021] [Indexed: 02/06/2023] Open
Abstract
An accelerator-based boron neutron capture therapy (BNCT) system employing a solid-state Li target can achieve sufficient neutron flux for treatment although the neutron flux is reduced over the lifetime of its target. In this study, the reduction was examined in the five targets, and a model was then established to represent the neutron flux. In each target, a reduction in neutron flux was observed based on the integrated proton charge on the target, and its reduction reached 28% after the integrated proton charge of 2.52 × 106 mC was delivered to the target in the system. The calculated neutron flux acquired by the model was compared to the measured neutron flux based on an integrated proton charge, and the mean discrepancies were less than 0.1% in all the targets investigated. These discrepancies were comparable among the five targets examined. Thus, the reduction of the neutron flux can be represented by the model. Additionally, by adequately revising the model, it may be applicable to other BNCT systems employing a Li target, thus furthering research in this direction. Therefore, the established model will play an important role in the accelerator-based BNCT system with a solid-state Li target in controlling neutron delivery and understanding the neutron output characteristics.
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Malouff TD, Seneviratne DS, Ebner DK, Stross WC, Waddle MR, Trifiletti DM, Krishnan S. Boron Neutron Capture Therapy: A Review of Clinical Applications. Front Oncol 2021; 11:601820. [PMID: 33718149 PMCID: PMC7952987 DOI: 10.3389/fonc.2021.601820] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 01/27/2021] [Indexed: 01/22/2023] Open
Abstract
Boron neutron capture therapy (BNCT) is an emerging treatment modality aimed at improving the therapeutic ratio for traditionally difficult to treat tumors. BNCT utilizes boronated agents to preferentially deliver boron-10 to tumors, which, after undergoing irradiation with neutrons, yields litihium-7 and an alpha particle. The alpha particle has a short range, therefore preferentially affecting tumor tissues while sparing more distal normal tissues. To date, BNCT has been studied clinically in a variety of disease sites, including glioblastoma multiforme, meningioma, head and neck cancers, lung cancers, breast cancers, hepatocellular carcinoma, sarcomas, cutaneous malignancies, extramammary Paget's disease, recurrent cancers, pediatric cancers, and metastatic disease. We aim to provide an up-to-date and comprehensive review of the studies of each of these disease sites, as well as a review on the challenges facing adoption of BNCT.
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Affiliation(s)
- Timothy D Malouff
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, United States
| | | | - Daniel K Ebner
- Warren Alpert Medical School, Brown University, Providence, RI, United States
| | - William C Stross
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, United States
| | - Mark R Waddle
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, United States
| | - Daniel M Trifiletti
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, United States
| | - Sunil Krishnan
- Department of Radiation Oncology, Mayo Clinic, Jacksonville, FL, United States
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Nakamura S, Igaki H, Ito M, Okamoto H, Nishioka S, Iijima K, Nakayama H, Takemori M, Imamichi S, Kashihara T, Takahashi K, Inaba K, Okuma K, Murakami N, Abe Y, Nakayama Y, Masutani M, Nishio T, Itami J. Characterization of the relationship between neutron production and thermal load on a target material in an accelerator-based boron neutron capture therapy system employing a solid-state Li target. PLoS One 2019; 14:e0225587. [PMID: 31756237 PMCID: PMC6874357 DOI: 10.1371/journal.pone.0225587] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 10/11/2019] [Indexed: 01/25/2023] Open
Abstract
An accelerator-based boron neutron capture therapy (BNCT) system that employs a solid-state Li target can achieve sufficient neutron flux derived from the 7Li(p,n) reaction. However, neutron production is complicated by the large thermal load expected on the target. The relationship between neutron production and thermal load was examined under various conditions. A target structure for neutron production consists of a Li target and a target basement. Four proton beam profiles were examined to vary the local thermal load on the target structure while maintaining a constant total thermal load. The efficiency of neutron production was evaluated with respect to the total number of protons delivered to the target structure. The target structure was also evaluated by observing its surface after certain numbers of protons were delivered. The yield of the sputtering effect was calculated via a Monte Carlo simulation to investigate whether it caused complications in neutron production. The efficiency of neutron production and the amount of damage done depended on the proton profile. A more focused proton profile resulted in greater damage. The efficiency decreased as the total number of protons delivered to the target structure increased, and the rate of decrease depended on the proton profile. The sputtering effect was not sufficiently large to be a main factor in the reduction in neutron production. The proton beam profile on the target structure was found to be important to the stable operation of the system with a solid-state Li target. The main factor in the rate of reduction in neutron production was found to be the local thermal load induced by proton irradiation of the target.
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Affiliation(s)
- Satoshi Nakamura
- Department of Medical Physics, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan
| | - Hiroshi Igaki
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan
- Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
- * E-mail:
| | - Masashi Ito
- Department of Radiology, National Center for Global Health and Medicine, Shinjuku-ku, Tokyo, Japan
| | - Hiroyuki Okamoto
- Department of Medical Physics, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan
| | - Shie Nishioka
- Department of Medical Physics, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan
| | - Kotaro Iijima
- Department of Medical Physics, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
| | - Hiroki Nakayama
- Department of Medical Physics, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
- Department of Radiological Science, Graduate School of Human Health Sciences, Arakawa-ku, Tokyo, Japan
| | - Mihiro Takemori
- Department of Medical Physics, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
- Department of Radiological Science, Graduate School of Human Health Sciences, Arakawa-ku, Tokyo, Japan
| | - Shoji Imamichi
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan
- Lab of Collaborative Research, Division of Cellular Signaling, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan
| | - Tairo Kashihara
- Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
| | - Kana Takahashi
- Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
| | - Koji Inaba
- Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
| | - Kae Okuma
- Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
| | - Naoya Murakami
- Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
| | - Yoshihisa Abe
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan
- Department of Radiological Technology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
| | - Yuko Nakayama
- Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
| | - Mitsuko Masutani
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan
- Lab of Collaborative Research, Division of Cellular Signaling, National Cancer Center Research Institute, Chuo-ku, Tokyo, Japan
- Center for Bioinformatics and Molecular Medicine, Department of Frontier Life Sciences, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto, Nagasaki, Japan
| | - Teiji Nishio
- Department of Medical Physics, Graduate School of Medicine, Tokyo Women’s Medical University, Shinjuku-ku, Tokyo, Japan
| | - Jun Itami
- Department of Medical Physics, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Chuo-ku, Tokyo, Japan
- Department of Radiation Oncology, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan
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Suzuki M. Boron neutron capture therapy (BNCT): a unique role in radiotherapy with a view to entering the accelerator-based BNCT era. Int J Clin Oncol 2019; 25:43-50. [PMID: 31168726 DOI: 10.1007/s10147-019-01480-4] [Citation(s) in RCA: 110] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 05/29/2019] [Indexed: 12/01/2022]
Abstract
Boron neutron capture therapy (BNCT) has a unique property of tumor-cell-selective heavy-particle irradiation. BNCT can form large dose gradients between cancer cells and normal cells, even if the two types of cells are mingled at the tumor margin. This property makes it possible for BNCT to be used for pre-irradiated locally recurrent tumors. Shallow-seated, locally recurrent lesions have been treated with BNCT because of the poor penetration of neutrons in the human body. BNCT has been used in clinical studies for recurrent malignant gliomas and head and neck cancers using neutron beams derived from research reactors, although further investigation is warranted because of the small number of patients. In the latter part of this review, the development of accelerator-based neutron sources is described. BNCT for common cancers will become available at medical institutes that are equipped with an accelerator-based BNCT system. Multiple metastatic lung tumors have been investigated as one of the new treatment candidates because BNCT can deliver curative doses of radiation to the tumors while sparing normal lung tissue. Further basic and clinical studies are needed to move toward an era of accelerator-based BNCT when more patients suffering from refractory cancers will be treated.
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Affiliation(s)
- Minoru Suzuki
- Particle Radiation Oncology Research Center, Institute for Integrated Radiation and Nuclear Science, Kyoto University, 2-1010, Asashiro-nishi, Kumatori-cho, Sennan-gun, Osaka, 590-0494, Japan.
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7
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He T, Chittur SV, Musah RA. Impact on Glioblastoma U87 Cell Gene Expression of a Carborane Cluster-Bearing Amino Acid: Implications for Carborane Toxicity in Mammalian Cells. ACS Chem Neurosci 2019; 10:1524-1534. [PMID: 30475580 DOI: 10.1021/acschemneuro.8b00512] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Carboranes have been extensively investigated as potential drugs for the treatment of malignant human brain tumors by boron neutron capture therapy (BNCT). This noninvasive treatment modality utilizes compounds containing the nonradioactive isotope 10B which has a high propensity to capture slow neutrons. In response, it emits high energy α-particles that kill the cell. We have successfully synthesized a boron delivery agent by installing a boron-rich m-carborane within the amino acid cysteine. Rapid uptake of this compound into U87 glioblastoma cells within 5 min of exposure was observed, and fluorescence microscopy studies showed that it was retained intracellularly after 48 h. In the absence of thermal neutrons, a cytostatic effect in U87 cells was observed at exposures ranging from 1 μM to 1 mM relative to the control, while no change was observed at 1-0.01 μM. Microarray studies unveiled a wide range of unique changes in the gene expression profile of the U87 cells, particularly for the genes associated with cell cycle, which were observed to be greatly suppressed after treatment with the compound. These results were validated by qPCR studies. Although the compound was designed for BNCT, its distinctive impacts on gene regulation reveal that it and other carborane-containing cluster molecules may exert unique heretofore unknown effects on the transcriptome, even in the absence of applied radiation.
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Affiliation(s)
- Tianyu He
- Department of Chemistry, University at Albany, State University of New York, 1400 Washington Avenue, Albany, New York 12222, United States
| | - Sridar V. Chittur
- Center for Functional Genomics, University at Albany, State University of New York, 1 Discovery Drive, Rensselaer, New York 12144, United States
| | - Rabi A. Musah
- Department of Chemistry, University at Albany, State University of New York, 1400 Washington Avenue, Albany, New York 12222, United States
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8
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Nakamura S, Igaki H, Okamoto H, Wakita A, Ito M, Imamichi S, Nishioka S, Iijima K, Nakayama H, Takemori M, Kobayashi K, Abe Y, Okuma K, Takahashi K, Inaba K, Murakami N, Nakayama Y, Nishio T, Masutani M, Itami J. Dependence of neutrons generated by 7Li(p,n) reaction on Li thickness under free-air condition in accelerator-based boron neutron capture therapy system employing solid-state Li target. Phys Med 2019; 58:121-130. [PMID: 30824143 DOI: 10.1016/j.ejmp.2019.02.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 01/22/2019] [Accepted: 02/12/2019] [Indexed: 10/27/2022] Open
Abstract
PURPOSE An accelerator-based boron neutron capture therapy (BNCT) system with a solid-state Li target is reported to have degradation of the Li target. The degradation reduces the Li thickness, which may change spectra of the generated neutrons corresponding to the Li thickness. This study aims to examine the relationship between the Li thickness and the generated neutrons and to investigate the effects of the Li thickness on the absorbed dose in BNCT. METHOD The neutron energy spectra were calculated via Monte Carlo simulation for Li thicknesses ranging from 20 to 150 μm. Using the system, the saturated radioactivity of gold induced by reactions between 197Au and the generated neutrons was evaluated with the simulation and the measurement, and those were compared. Additionally, for each Li thickness, the saturated radioactivity was compared with the number of generated neutrons. The absorbed doses delivered by 10B(n,α)7Li, 14N(n,p)14C, 1H(n, g)2H, and (n,n') reactions in water were also calculated for each Li thickness. RESULTS The measurement and simulation indicated a reduction in the number of neutrons due to the degradation of the Li target. However, the absorbed doses were comparable for each Li thickness when the requisite number of neutrons for BNCT was delivered. Additionally, the saturated radioactivity of 198Au could be a surrogate for the number of neutrons even if the Li thickness was varied. CONCLUSIONS No notable effect to the absorbed dose was observed when required neutron fluence was delivered in the BNCT even if the degradation of the Li was observed.
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Affiliation(s)
- Satoshi Nakamura
- Department of Medical Physics, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan.
| | - Hiroshi Igaki
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Hiroyuki Okamoto
- Department of Medical Physics, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Akihisa Wakita
- Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Masashi Ito
- Department of Radiology, National Center for Global Health and Medicine, Toyama 1-21-1, Shinjuku-ku, Tokyo 162-8655, Japan
| | - Shoji Imamichi
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Division of Genetics, National Cancer Center Research Institute, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Shie Nishioka
- Department of Medical Physics, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Kotaro Iijima
- Department of Medical Physics, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Hiroki Nakayama
- Department of Medical Physics, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Department of Radiological Science, Graduate School of Human Health Sciences, Higashi-ogu 7-2-10, Arakawa-ku, Tokyo 116-8551, Japan
| | - Mihiro Takemori
- Department of Medical Physics, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Department of Radiological Science, Graduate School of Human Health Sciences, Higashi-ogu 7-2-10, Arakawa-ku, Tokyo 116-8551, Japan
| | - Kazuma Kobayashi
- Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Yoshihisa Abe
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Department of Radiological Technology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Kae Okuma
- Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Kana Takahashi
- Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Koji Inaba
- Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Naoya Murakami
- Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Yuko Nakayama
- Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
| | - Teiji Nishio
- Department of Medical Physics, Graduate School of Medicine, Tokyo Women's University, Kawada-cho 8-1, Shinjuku-ku, Tokyo 162-8666, Japan
| | - Mitsuko Masutani
- Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Division of Genetics, National Cancer Center Research Institute, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Department of Frontier Life Sciences, Nagasaki University Graduate School of Biomedical Sciences, Sakamoto 1-7-1, Nagasaki 852-8588, Japan
| | - Jun Itami
- Department of Medical Physics, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Division of Research and Development for Boron Neutron Capture Therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan; Department of Radiation Oncology, National Cancer Center Hospital, Tsukiji 5-1-1, Chuo-ku, Tokyo 104-0045, Japan
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Nakamura S, Wakita A, Ito M, Okamoto H, Nishioka S, Iijima K, Kobayashi K, Nishio T, Igaki H, Itami J. Modeling the detection efficiency of an HP-Ge detector for use in boron neutron capture therapy. Appl Radiat Isot 2017; 125:80-85. [PMID: 28414991 DOI: 10.1016/j.apradiso.2017.03.027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 02/24/2017] [Accepted: 03/30/2017] [Indexed: 11/15/2022]
Abstract
The multi-foil method is commonly used to determine upon an energy spectrum of neutrons in boron neutron capture therapy. The method requires to measure the radioactivation of the foils. This study develops a simple modeling procedure of a high-purity Ge detector, which is used to measure the radioactivation, in order to calculate the detection efficiency with GEANT4. By changing four parameters from their manufacturing specifications of the detector, the simulated detection efficiency is able to reproduce the actual detection efficiency.
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Affiliation(s)
- Satoshi Nakamura
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan.
| | - Akihisa Wakita
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Masashi Ito
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Hiroyuki Okamoto
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Shie Nishioka
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Kotaro Iijima
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Kazuma Kobayashi
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Teiji Nishio
- Department of Medical Physics, Graduate School of Medicine, Tokyo Women's University, 8-1 Kawada-cho, shinjuku-ku, Tokyo 162-8666, Japan
| | - Hiroshi Igaki
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
| | - Jun Itami
- Department of Radiation Oncology, National Cancer Center Hospital, 5-1-1 Tsukiji, Chuo-ku, Tokyo 104-0045, Japan
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10
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NAKAMURA S, IMAMICHI S, MASUMOTO K, ITO M, WAKITA A, OKAMOTO H, NISHIOKA S, IIJIMA K, KOBAYASHI K, ABE Y, IGAKI H, KURITA K, NISHIO T, MASUTANI M, ITAMI J. Evaluation of radioactivity in the bodies of mice induced by neutron exposure from an epi-thermal neutron source of an accelerator-based boron neutron capture therapy system. PROCEEDINGS OF THE JAPAN ACADEMY. SERIES B, PHYSICAL AND BIOLOGICAL SCIENCES 2017; 93:821-831. [PMID: 29225308 PMCID: PMC5790759 DOI: 10.2183/pjab.93.051] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2017] [Accepted: 09/08/2017] [Indexed: 06/07/2023]
Abstract
This study aimed to evaluate the residual radioactivity in mice induced by neutron irradiation with an accelerator-based boron neutron capture therapy (BNCT) system using a solid Li target. The radionuclides and their activities were evaluated using a high-purity germanium (HP-Ge) detector. The saturated radioactivity of the irradiated mouse was estimated to assess the radiation protection needs for using the accelerator-based BNCT system. 24Na, 38Cl, 80mBr, 82Br, 56Mn, and 42K were identified, and their saturated radioactivities were (1.4 ± 0.1) × 102, (2.2 ± 0.1) × 101, (3.4 ± 0.4) × 102, 2.8 ± 0.1, 8.0 ± 0.1, and (3.8 ± 0.1) × 101 Bq/g/mA, respectively. The 24Na activation rate at a given neutron fluence was found to be consistent with the value reported from nuclear-reactor-based BNCT experiments. The induced activity of each nuclide can be estimated by entering the saturated activity of each nuclide, sample mass, irradiation time, and proton current into the derived activation equation in our accelerator-based BNCT system.
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Affiliation(s)
- Satoshi NAKAMURA
- Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan
- Department of Physics, Rikkyo University, Tokyo, Japan
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
| | - Shoji IMAMICHI
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
- Division of Genetics, National Cancer Center Research Institute, Tokyo, Japan
| | | | - Masashi ITO
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
- Department of Radiological Technology, National Cancer Center Hospital, Tokyo, Japan
| | - Akihisa WAKITA
- Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
| | - Hiroyuki OKAMOTO
- Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
| | - Shie NISHIOKA
- Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
| | - Kotaro IIJIMA
- Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan
| | - Kazuma KOBAYASHI
- Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
| | - Yoshihisa ABE
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
- Department of Radiological Technology, National Cancer Center Hospital, Tokyo, Japan
| | - Hiroshi IGAKI
- Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
| | | | - Teiji NISHIO
- Department of Medical Physics, Graduate School of Medicine, Tokyo Women’s University, Tokyo, Japan
| | - Mitsuko MASUTANI
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
- Division of Genetics, National Cancer Center Research Institute, Tokyo, Japan
- Department of Frontier Life Sciences, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, Japan
| | - Jun ITAMI
- Department of Radiation Oncology, National Cancer Center Hospital, Tokyo, Japan
- Division of Research and Development for boron neutron capture therapy, National Cancer Center Exploratory Oncology Research & Clinical Trial Center, Tokyo, Japan
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Additive effect of BPA and Gd-DTPA for application in accelerator-based neutron source. Appl Radiat Isot 2015; 106:247-50. [DOI: 10.1016/j.apradiso.2015.07.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Revised: 06/26/2015] [Accepted: 07/24/2015] [Indexed: 11/23/2022]
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12
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Cathepsin L suppression increases the radiosensitivity of human glioma U251 cells via G2/M cell cycle arrest and DNA damage. Acta Pharmacol Sin 2015; 36:1113-25. [PMID: 26095040 DOI: 10.1038/aps.2015.36] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Accepted: 03/13/2015] [Indexed: 01/08/2023] Open
Abstract
AIM Cathepsin L is a lysosomal cysteine protease that plays important roles in cancer tumorigenesis, proliferation and chemotherapy resistance. The aim of this study was to determine how cathepsin L regulated the radiosensitivity of human glioma cells in vitro. METHODS Human glioma U251 cells (harboring the mutant type p53 gene) and U87 cells (harboring the wide type p53 gene) were irradiated with X-rays. The expression of cathepsin L was analyzed using Western blot and immunofluorescence assays. Cell survival and DNA damage were evaluated using clonogenic and comet assays, respectively. Flow cytometry was used to detect the cell cycle distribution. Apoptotic cells were observed using Hoechst 33258 staining and fluorescence microscopy. RESULTS Irradiation significantly increased the cytoplasmic and nuclear levels of cathepsin L in U251 cells but not in U87 cells. Treatment with the specific cathepsin L inhibitor Z-FY-CHO (10 μmol/L) or transfection with cathepsin L shRNA significantly increased the radiosensitivity of U251 cells. Both suppression and knockdown of cathepsin L in U251 cells increased irradiation-induced DNA damage and G2/M phase cell cycle arrest. Both suppression and knockdown of cathepsin L in U251 cells also increased irradiation-induced apoptosis, as shown by the increased levels of Bax and decreased levels of Bcl-2. CONCLUSION Cathepsin L is involved in modulation of radiosensitivity in human glioma U251 cells (harboring the mutant type p53 gene) in vitro.
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Zaboronok A, Yamamoto T, Nakai K, Yoshida F, Uspenskii S, Selyanin M, Zelenetskii A, Matsumura A. Hyaluronic acid as a potential boron carrier for BNCT: Preliminary evaluation. Appl Radiat Isot 2015; 106:181-4. [PMID: 26302663 DOI: 10.1016/j.apradiso.2015.08.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 08/13/2015] [Accepted: 08/16/2015] [Indexed: 11/26/2022]
Abstract
Hyaluronic acid (HA), a nonimmunogenic, biocompatible polymer found in different biological tissues, has the potential to attach to CD44 receptors on the surface of certain cancer cells, where the receptor is overexpressed compared with normal cells. Boron-hyaluronic acid (BHA) was tested for its feasibility as a potential agent for BNCT. BHA with low-viscosity 30 kDa HA could be administered by intravenous injection. The compound showed a certain degree of cytotoxicity and accumulation in C6 rat glioma cells in vitro. Instability of the chelate bonds between boron and HA and/or insufficient specificity of CD44 receptors on C6 cells to BHA could account for the insufficient in vitro accumulation. To ensure the future eligibility of BHA for BNCT experiments, using alternative tumor cell lines and chemically securing the chelate bonds or synthesizing BHA with boron covalently attached to HA might be required.
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Affiliation(s)
- A Zaboronok
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - T Yamamoto
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - K Nakai
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan.
| | - F Yoshida
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
| | - S Uspenskii
- Enikolopov Institute of Synthetic Polymer Materials, Russian Academy of Sciences, Moscow, Russian Federation; International Research Center "Martinex", Moscow, Russian Federation
| | - M Selyanin
- International Research Center "Martinex", Moscow, Russian Federation
| | - A Zelenetskii
- Enikolopov Institute of Synthetic Polymer Materials, Russian Academy of Sciences, Moscow, Russian Federation
| | - Akira Matsumura
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Tsukuba, Japan
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Brandão SF, Campos TPR. Intracavitary moderator balloon combined with (252)Cf brachytherapy and boron neutron capture therapy, improving dosimetry in brain tumour and infiltrations. Br J Radiol 2015; 88:20140829. [PMID: 25927876 PMCID: PMC4628521 DOI: 10.1259/bjr.20140829] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2014] [Revised: 04/28/2015] [Accepted: 04/30/2015] [Indexed: 11/05/2022] Open
Abstract
OBJECTIVE This article proposes a combination of californium-252 ((252)Cf) brachytherapy, boron neutron capture therapy (BNCT) and an intracavitary moderator balloon catheter applied to brain tumour and infiltrations. METHODS Dosimetric evaluations were performed on three protocol set-ups: (252)Cf brachytherapy combined with BNCT (Cf-BNCT); Cf-BNCT with a balloon catheter filled with light water (LWB) and the same set-up with heavy water (HWB). RESULTS Cf-BNCT-HWB has presented dosimetric advantages to Cf-BNCT-LWB and Cf-BNCT in infiltrations at 2.0-5.0 cm from the balloon surface. However, Cf-BNCT-LWB has shown superior dosimetry up to 2.0 cm from the balloon surface. CONCLUSION Cf-BNCT-HWB and Cf-BNCT-LWB protocols provide a selective dose distribution for brain tumour and infiltrations, mainly further from the (252)Cf source, sparing the normal brain tissue. ADVANCES IN KNOWLEDGE Malignant brain tumours grow rapidly and often spread to adjacent brain tissues, leading to death. Improvements in brain radiation protocols have been continuously achieved; however, brain tumour recurrence is observed in most cases. Cf-BNCT-LWB and Cf-BNCT-HWB represent new modalities for selectively combating brain tumour infiltrations and metastasis.
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Affiliation(s)
- S F Brandão
- Departamento de Engenharia Nuclear, Universidade Federal de Minas Gerais, Escola de Engenharia, Belo Horizonte, Minas Gerais, Brazil
| | - T P R Campos
- Departamento de Engenharia Nuclear, Universidade Federal de Minas Gerais, Escola de Engenharia, Belo Horizonte, Minas Gerais, Brazil
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Pozzi ECC, Trivillin VA, Colombo LL, Monti Hughes A, Thorp SI, Cardoso JE, Garabalino MA, Molinari AJ, Heber EM, Curotto P, Miller M, Itoiz ME, Aromando RF, Nigg DW, Schwint AE. Boron neutron capture therapy (BNCT) for liver metastasis in an experimental model: dose–response at five-week follow-up based on retrospective dose assessment in individual rats. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2013; 52:481-491. [PMID: 24077963 DOI: 10.1007/s00411-013-0490-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2013] [Accepted: 08/24/2013] [Indexed: 06/02/2023]
Abstract
Boron neutron capture therapy (BNCT) was proposed for untreatable colorectal liver metastases. Employing an experimental model of liver metastases in rats, we recently demonstrated that BNCT mediated by boronophenylalanine (BPA-BNCT) at 13 Gy prescribed to tumor is therapeutically useful at 3-week follow-up. The aim of the present study was to evaluate dose–response at 5-week follow-up, based on retrospective dose assessment in individual rats. BDIX rats were inoculated with syngeneic colon cancer cells DHD/K12/TRb. Tumor-bearing animals were divided into three groups: BPA-BNCT (n = 19), Beam only (n = 8) and Sham (n = 7) (matched manipulation, no treatment). For each rat, neutron flux was measured in situ and boron content was measured in a pre-irradiation blood sample for retrospective individual dose assessment. For statistical analysis (ANOVA), individual data for the BPA-BNCT group were pooled according to absorbed tumor dose, BPA-BNCT I: 4.5–8.9 Gy and BPA-BNCT II: 9.2–16 Gy. At 5 weeks post-irradiation, the tumor surface area post-treatment/pre-treatment ratio was 12.2 ± 6.6 for Sham, 7.8 ± 4.1 for Beam only, 4.4 ± 5.6 for BPA-BNCT I and 0.45 ± 0.20 for BPA-BNCT II; tumor nodule weight was 750 ± 480 mg for Sham, 960 ± 620 mg for Beam only, 380 ± 720 mg for BPA-BNCT I and 7.3 ± 5.9 mg for BPA-BNCT II. The BPA-BNCT II group exhibited statistically significant tumor control with no contributory liver toxicity. Potential threshold doses for tumor response and significant tumor control were established at 6.1 and 9.2 Gy, respectively.
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Garabalino MA, Heber EM, Monti Hughes A, González SJ, Molinari AJ, Pozzi ECC, Nievas S, Itoiz ME, Aromando RF, Nigg DW, Bauer W, Trivillin VA, Schwint AE. Biodistribution of sodium borocaptate (BSH) for boron neutron capture therapy (BNCT) in an oral cancer model. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2013; 52:351-361. [PMID: 23591915 DOI: 10.1007/s00411-013-0467-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2012] [Accepted: 03/23/2013] [Indexed: 06/02/2023]
Abstract
Boron neutron capture therapy (BNCT) is based on selective accumulation of ¹⁰B carriers in tumor followed by neutron irradiation. We previously proved the therapeutic success of BNCT mediated by the boron compounds boronophenylalanine and sodium decahydrodecaborate (GB-10) in the hamster cheek pouch oral cancer model. Based on the clinical relevance of the boron carrier sodium borocaptate (BSH) and the knowledge that the most effective way to optimize BNCT is to improve tumor boron targeting, the specific aim of this study was to perform biodistribution studies of BSH in the hamster cheek pouch oral cancer model and evaluate the feasibility of BNCT mediated by BSH at nuclear reactor RA-3. The general aim of these studies is to contribute to the knowledge of BNCT radiobiology and optimize BNCT for head and neck cancer. Sodium borocaptate (50 mg ¹⁰B/kg) was administered to tumor-bearing hamsters. Groups of 3-5 animals were killed humanely at nine time-points, 3-12 h post-administration. Samples of blood, tumor, precancerous pouch tissue, normal pouch tissue and other clinically relevant normal tissues were processed for boron measurement by optic emission spectroscopy. Tumor boron concentration peaked to therapeutically useful boron concentration values of 24-35 ppm. The boron concentration ratio tumor/normal pouch tissue ranged from 1.1 to 1.8. Pharmacokinetic curves showed that the optimum interval between BSH administration and neutron irradiation was 7-11 h. It is concluded that BNCT mediated by BSH at nuclear reactor RA-3 would be feasible.
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Affiliation(s)
- Marcela A Garabalino
- Department of Radiobiology, National Atomic Energy Commission-CNEA, Avenida General Paz 1499, B1650KNA, San Martin, Buenos Aires, Argentina
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Brandão SDF, Campos TPRD. Comparative dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for brain tumors. Radiol Bras 2013. [DOI: 10.1590/s0100-39842013000400008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Objective Comparative analysis of dosimetry in intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT for treatment of brain tumors. Materials and Methods Simulations of intracavitary balloon catheter brachytherapy with I-125 and in Cf-252 brachytherapy combined with BNCT were performed with the MCNP5 code, modeling the treatment of a brain tumor on a voxel computational phantom representing a human head. Absorbed dose rates were converted into biologically weighted dose rates. Results Intracavitary balloon catheter brachytherapy with I-125 produced biologically weighted mean dose rates of 3.2E-11, 1.3E-10, 1.9E-11 and 6.9E-13 RBE.Gy.h-1.p-1.s, respectively, on the healthy tissue, on the balloon periphery and on the I 1 and I 2 tumor infiltration zones. On the other hand, Cf-252 brachytherapy combined with BNCT produced a biologically weighted mean dose rate of 5.2E-09, 2.3E-07, 8.7E-09 and 2.4E-09 RBE.Gy.h-1.p-1.s, respectively on the healthy tissue, on the target tumor and on the I 1 and I 2 infiltration zones. Conclusion Cf-252 brachytherapy combined with BNCT delivered a selective irradiation to the target tumor and to infiltration zones, while intracavitary balloon catheter brachytherapy with I-125 delivered negligible doses on the tumor infiltration zones.
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Boron neutron capture therapy demonstrated in mice bearing EMT6 tumors following selective delivery of boron by rationally designed liposomes. Proc Natl Acad Sci U S A 2013; 110:6512-7. [PMID: 23536304 DOI: 10.1073/pnas.1303437110] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The application of boron neutron capture therapy (BNCT) following liposomal delivery of a (10)B-enriched polyhedral borane and a carborane against mouse mammary adenocarcinoma solid tumors was investigated. Unilamellar liposomes with a mean diameter of 134 nm or less, composed of an equimolar mixture of cholesterol and 1,2-distearoyl-sn-glycero-3-phosphocholine and incorporating Na3[1-(2'-B10H9)-2-NH3B10H8] in the aqueous interior and K[nido-7-CH3(CH2)15-7,8-C2B9H11] in the bilayer, were injected into the tail veins of female BALB/c mice bearing right flank EMT6 tumors. Biodistribution studies indicated that two identical injections given 24 h apart resulted in tumor boron levels exceeding 67 µg/g tumor at 54 h--with tumor/blood boron ratios being greatest at 96 h (5.68:1; 43 µg boron/g tumor)--following the initial injection. For BNCT experiments, tumor-bearing mice were irradiated 54 h after the initial injection for 30 min with thermal neutrons, resulting in a total fluence of 1.6 × 10(12) neutrons per cm(2) (±7%). Significant suppression of tumor growth was observed in mice given BNCT vs. control mice (only 424% increase in tumor volume at 14 d post irradiation vs. 1551% in untreated controls). In a separate experiment in which mice were given a second injection/irradiation treatment 7 d after the first, the tumor growth was vastly diminished (186% tumor volume increase at 14 d). A similar response was obtained for mice irradiated for 60 min (169% increase at 14 d), suggesting that neutron fluence was the limiting factor controlling BNCT efficacy in this study.
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Barth RF, Vicente MGH, Harling OK, Kiger WS, Riley KJ, Binns PJ, Wagner FM, Suzuki M, Aihara T, Kato I, Kawabata S. Current status of boron neutron capture therapy of high grade gliomas and recurrent head and neck cancer. Radiat Oncol 2012; 7:146. [PMID: 22929110 PMCID: PMC3583064 DOI: 10.1186/1748-717x-7-146] [Citation(s) in RCA: 291] [Impact Index Per Article: 24.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Accepted: 07/23/2012] [Indexed: 11/25/2022] Open
Abstract
Boron neutron capture therapy (BNCT) is a biochemically targeted radiotherapy based on the nuclear capture and fission reactions that occur when non-radioactive boron-10, which is a constituent of natural elemental boron, is irradiated with low energy thermal neutrons to yield high linear energy transfer alpha particles and recoiling lithium-7 nuclei. Clinical interest in BNCT has focused primarily on the treatment of high grade gliomas, recurrent cancers of the head and neck region and either primary or metastatic melanoma. Neutron sources for BNCT currently have been limited to specially modified nuclear reactors, which are or until the recent Japanese natural disaster, were available in Japan, the United States, Finland and several other European countries, Argentina and Taiwan. Accelerators producing epithermal neutron beams also could be used for BNCT and these are being developed in several countries. It is anticipated that the first Japanese accelerator will be available for therapeutic use in 2013. The major hurdle for the design and synthesis of boron delivery agents has been the requirement for selective tumor targeting to achieve boron concentrations in the range of 20 μg/g. This would be sufficient to deliver therapeutic doses of radiation with minimal normal tissue toxicity. Two boron drugs have been used clinically, a dihydroxyboryl derivative of phenylalanine, referred to as boronophenylalanine or “BPA”, and sodium borocaptate or “BSH” (Na2B12H11SH). In this report we will provide an overview of other boron delivery agents that currently are under evaluation, neutron sources in use or under development for BNCT, clinical dosimetry, treatment planning, and finally a summary of previous and on-going clinical studies for high grade gliomas and recurrent tumors of the head and neck region. Promising results have been obtained with both groups of patients but these outcomes must be more rigorously evaluated in larger, possibly randomized clinical trials. Finally, we will summarize the critical issues that must be addressed if BNCT is to become a more widely established clinical modality for the treatment of those malignancies for which there currently are no good treatment options.
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Affiliation(s)
- Rolf F Barth
- Department of Pathology, The Ohio State University, 165 Hamilton Hall, 1645 Neil Avenue, Columbus, OH, 43210, USA.
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Pozzi ECC, Cardoso JE, Colombo LL, Thorp S, Monti Hughes A, Molinari AJ, Garabalino MA, Heber EM, Miller M, Itoiz ME, Aromando RF, Nigg DW, Quintana J, Trivillin VA, Schwint AE. Boron neutron capture therapy (BNCT) for liver metastasis: therapeutic efficacy in an experimental model. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2012; 51:331-339. [PMID: 22544068 DOI: 10.1007/s00411-012-0419-8] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 04/14/2012] [Indexed: 05/31/2023]
Abstract
Boron neutron capture therapy (BNCT) was proposed for untreatable colorectal liver metastases. The present study evaluates tumor control and potential radiotoxicity of BNCT in an experimental model of liver metastasis. BDIX rats were inoculated with syngeneic colon cancer cells DHD/K12/TRb. Tumor-bearing animals were divided into three groups: BPA-BNCT, boronophenylalanine (BPA) + neutron irradiation; Beam only, neutron irradiation; Sham, matched manipulation. The total absorbed dose administered with BPA-BNCT was 13 ± 3 Gy in tumor and 9 ± 2 Gy in healthy liver. Three weeks post-treatment, the tumor surface area post-treatment/pre-treatment ratio was 0.46 ± 0.20 for BPA-BNCT, 2.7 ± 1.8 for Beam only and 4.5 ± 3.1 for Sham. The pre-treatment tumor nodule mass of 48 ± 19 mg fell significantly to 19 ± 16 mg for BPA-BNCT, but rose significantly to 140 ± 106 mg for Beam only and to 346 ± 302 mg for Sham. For both end points, the differences between the BPA-BNCT group and each of the other groups were statistically significant (ANOVA). No clinical, macroscopic or histological normal liver radiotoxicity was observed. It is concluded that BPA-BNCT induced a significant remission of experimental colorectal tumor nodules in liver with no contributory liver toxicity.
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Affiliation(s)
- Emiliano C C Pozzi
- Department Radiobiology, National Atomic Energy Commission, Avenida General Paz 1499, B1650KNA, San Martin, Province Buenos Aires, Argentina
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Heber EM, Kueffer PJ, Lee MW, Hawthorne MF, Garabalino MA, Molinari AJ, Nigg DW, Bauer W, Hughes AM, Pozzi ECC, Trivillin VA, Schwint AE. Boron delivery with liposomes for boron neutron capture therapy (BNCT): biodistribution studies in an experimental model of oral cancer demonstrating therapeutic potential. RADIATION AND ENVIRONMENTAL BIOPHYSICS 2012; 51:195-204. [PMID: 22271404 DOI: 10.1007/s00411-011-0399-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Accepted: 12/27/2011] [Indexed: 05/31/2023]
Abstract
Boron neutron capture therapy (BNCT) combines selective accumulation of (10)B carriers in tumor tissue with subsequent neutron irradiation. We previously demonstrated the therapeutic efficacy of BNCT in the hamster cheek pouch oral cancer model. Optimization of BNCT depends largely on improving boron targeting to tumor cells. Seeking to maximize the potential of BNCT for the treatment for head and neck cancer, the aim of the present study was to perform boron biodistribution studies in the oral cancer model employing two different liposome formulations that were previously tested for a different pathology, i.e., in experimental mammary carcinoma in BALB/c mice: (1) MAC: liposomes incorporating K[nido-7-CH(3)(CH(2))(15)-7,8-C(2)B(9)H(11)] in the bilayer membrane and encapsulating a hypertonic buffer, administered intravenously at 6 mg B per kg body weight, and (2) MAC-TAC: liposomes incorporating K[nido-7-CH(3)(CH(2))(15)-7,8-C(2)B(9)H(11)] in the bilayer membrane and encapsulating a concentrated aqueous solution of the hydrophilic species Na(3) [ae-B(20)H(17)NH(3)], administered intravenously at 18 mg B per kg body weight. Samples of tumor, precancerous and normal pouch tissue, spleen, liver, kidney, and blood were taken at different times post-administration and processed to measure boron content by inductively coupled plasma mass spectrometry. No ostensible clinical toxic effects were observed with the selected formulations. Both MAC and MAC-TAC delivered boron selectively to tumor tissue. Absolute tumor values for MAC-TAC peaked to 66.6 ± 16.1 ppm at 48 h and to 43.9 ± 17.6 ppm at 54 h with very favorable ratios of tumor boron relative to precancerous and normal tissue, making these protocols particularly worthy of radiobiological assessment. Boron concentration values obtained would result in therapeutic BNCT doses in tumor without exceeding radiotolerance in precancerous/normal tissue at the thermal neutron facility at RA-3.
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Affiliation(s)
- Elisa M Heber
- Department of Radiobiology, National Atomic Energy Commission, San Martin, Buenos Aires, Argentina
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Molinari AJ, Pozzi ECC, Hughes AM, Heber EM, Garabalino MA, Thorp SI, Miller M, Itoiz ME, Aromando RF, Nigg DW, Trivillin VA, Schwint AE. Tumor Blood Vessel “Normalization” Improves the Therapeutic Efficacy of Boron Neutron Capture Therapy (BNCT) in Experimental Oral Cancer. Radiat Res 2012; 177:59-68. [DOI: 10.1667/rr2729.1] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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