Our research field is in the field of therapeutic radiation biology in cancer. While technological advancements have improved treatment outcomes in radiotherapy, major challenges remain, such as controlling distant metastases and overcoming radioresistant tumors that results in local recurrence or distant metastasis. Our core research aims to activate antitumor immunity through radiation and to develop therapies that effectively combine radiotherapy with immunotherapy to control distant metastases. We are also working on establishing radioresistant tumor models to elucidate the underlying mechanisms of radioresistance and propose novel therapeutic strategies. Our research involves various types of radiation, including not only photon beams but also heavy ion and neutron beams, with a focus on tumors and the tumor microenvironment. In close collaboration with the Department of Radiation Oncology in the Graduate School of Medicine, we also engage in joint research across a broad range of topics, such as predicting radiosensitivity and metastatic potential using patient-derived samples.