Exploring Personalized Medicine in Radiotherapy for Lung Cancer

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K08080
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 52040:Radiological sciences-related
• Research Institution: Yamaguchi University
• Principal Investigator: Tanaka Hidekazu 山口大学, 大学院医学系研究科, 教授 (30509782)
• Co-Investigator(Kenkyū-buntansha): 椎木 健裕 山口大学, 医学部附属病院, 講師 (30610456)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 放射線治療 / EGFR変異 / 肺癌

Outline of Final Research Achievements

Because stereotactic radiotherapy for lung cancer had fewer local recurrences, whole-brain radiotherapy cases were analyzed. The intracranial control rate was significantly higher in EGFR mutation-positive patients than in negative patients. For in vitro analysis, colony formation was tested in three cell lines with EGFR mutations and two cell lines without mutations, the mutation-positive cell lines showed significantly fewer colonies. DNA double-strand breaks were evaluated using γH2AX. Although there was no difference in the number of foci between mutation-positive and mutation-negative cell lines at 30 minutes after irradiation, significantly more foci remained in the positive cell lines at 24 hours. The mutation-positive tumors were more radiosensitive than the mutation-negative tumors both in clinical and in vitro.

Free Research Field

放射線腫瘍学

Academic Significance and Societal Importance of the Research Achievements

薬物療法は腫瘍の遺伝子情報に応じて治療薬を選択することが当たり前になっている。しかし放射線治療はまだ遺伝子情報により治療内容が選択されることはない。本研究では遺伝子情報により放射線感受性が異なることを明らかにした。この結果をもとに感受性が高い遺伝子変異を有する場合、照射の線量を落とせる可能性がある。それにより有害事象を低減できる可能性がある。さらに今後、遺伝子情報に基づいて放射線治療の照射線量や照射範囲を決定する個別化放射線治療の礎となり得る。