Annual Report 2022
Central Radioisotope Division
Masamichi Ishiai, Akihiro Yanagihara, Gen Fujii, Hiroshi Tanooka, Mitsuko Masutani, Makoto Ihara, Shoji Imamichi, Kaima Tsukada, Takahiro Hamoya, Takahisa Hirai, Yui Kanai, Rikiya Imamura, Hideyuki Watanuma
Introduction
The Central Radioisotope Division is a joint usage facility composed of the Research Support Core of the Fundamental Innovative Oncology Core (FIOC) of the National Cancer Center (NCC) Research Institute. We provide advanced technical training and education for researchers in the NCC. We also support and advise on radiation-related cancer research.
The Team and What We Do
Our division manages radioisotope (RI) materials, gamma-ray irradiators (Gammacell 220 with Co-60 source and Gammacell 40 Exactor with Cs-137 source), and radiation-related equipment to promote advanced cancer research in a smooth manner. Our division also conducts radiation management studies so that researchers can use RI resources safely and effectively.
Research Activities
We have been conducting research on cancer risk after irradiation by several approaches. First, we have focused on the study of molecular mechanisms of cellular responses such as DNA damage signaling, DNA repair, and apoptosis pathway after DNA damage, including by irradiation. Second, we have developed a radiotherapy model by mouse. Third, through collaboration with the Department of Radiation Oncology at the NCC Hospital and industry, we conducted preclinical research as well as basic and translational studies of the accelerator-based boron neutron capture therapy (BNCT) system introduced in the NCC and research on boron carrier drugs. Fourth, we have studied about basic research on alpha-emitting nuclides for biological/medical use. Fifth, we have also investigated the molecular mechanisms of cancer chemoprevention. The research topics were presented at international and domestic conferences and published as treatises.
Facility Utilization Information
The usage frequency of gamma-ray irradiators and the used amounts of RI for the past five years are shown in Table 1 and 2, respectively.
Table 1. Number of times gamma-ray irradiators were used
Table 2. Used amounts of radioisotope (P-32) (MBq)
Education
We provide an annual course of education and train in radiation biology, handling of RI, and operating of gamma-ray irradiators.
Two graduate school students were trained in our division.
Future Prospects
A clinical trial for cancer patients using BNCT has been initiated in the NCC Hospital, so opportunities to handle neutron-irradiated cells have increased in our division. In addition, we have started the basic research on radionuclide therapy using alpha-ray emitting nuclide.
List of papers published in 2022
Journal
1. Imai T, Naruse M, Machida Y, Fujii G, Mutoh M, Ochiai M, Takahashi M, Nakagama H. Feeding a High-Fat Diet for a Limited Duration Increases Cancer Incidence in a Breast Cancer Model. Nutrition and cancer, 75:713-725, 2023
2. Sugiura S, Yamahira S, Tamura M, Shin K, Shibuta M, Satoh T, Matsuzawa Y, Fujii G, Yanagawa F, Mutoh M, Yanagisawa M, Kato R, Matsui H. Automated cell isolation from photodegradable hydrogel based on fluorescence image analysis. Biotechnology and bioengineering, 120:1492-1505, 2023
3. Imamura R, Saito M, Shimada M, Kobayashi J, Ishiai M, Matsumoto Y. APTX acts in DNA double-strand break repair in a manner distinct from XRCC4. Journal of radiation research, 64:485-495, 2023
4. Tanooka H. Radiation cancer risk at different dose rates: new dose-rate effectiveness factors derived from revised A-bomb radiation dosimetry data and non-tumor doses. Journal of radiation research, 63:1-7, 2022
5. Tong Y, Kikuhara S, Onodera T, Chen L, Myat AB, Imamichi S, Sasaki Y, Murakami Y, Nozaki T, Fujimori H, Masutani M. Radiosensitization to γ-Ray by Functional Inhibition of APOBEC3G . International journal of molecular sciences, 23:5069 , 2022