Development of combination therapy with molecular targeted drugs and internal/external radiation therapy for thyroid cancer

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K18269
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 56050:Otorhinolaryngology-related
• Research Institution: Kansai Medical University
• Principal Investigator: SAKAI Haruka 関西医科大学, 医学部, 研究員 (80757609)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 甲状腺癌 / 外照射 / I-131 / 分子標的薬 / レンバチニブ / 併用療法

Outline of Final Research Achievements

In this study, we focus on the synergistic effects of radiation therapy and lenvatinib, a molecularly targeted drug, on thyroid cancer and investigate a preclinical study on the antitumor effect and its mechanism of combination therapy. In experiments using thyroid cancer cell lines (K1, FTC-133) and their xenograft mice, we demonstrated that the combination therapy with external beam radiation and lenvatinib achieved a high antitumor effect, induced by apoptosis, cell cycle arrest in the G2/M phase, and an elevated concentration of lenvatinib in the irradiated tumor cells. The development of this study could lead to the establishment of a new combination therapy with molecular-targeted drugs and radiation therapy and its clinical application for refractory thyroid cancers.

Free Research Field

耳鼻咽喉科・頭頸部外科学

Academic Significance and Societal Importance of the Research Achievements

乳頭癌や濾胞癌などの分化型甲状腺癌は一般的に予後良好であるが、再発・転移性甲状腺癌の予後は不良である。分子標的薬や放射線治療（外照射、放射性ヨウ素内用療法）は単独でのみ用いられるがその治療効果は限定的であり、新たな治療法の開発が望まれている。分子標的薬と放射線治療を併用することで、より高い治療効果が得られ、再発・転移を伴う難治性甲状腺癌でも根治できる可能性がありその社会的意義は大きいと考えられる。