In-cell synthesis of anticancer drugs from non-toxic precursor compounds by monochromatic X-ray irradiation

2019 Fiscal Year Final Research Report

• Project/Area Number: 16K12910
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Medical systems
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Oguri Yoshiyuki 東京工業大学, 科学技術創成研究院, 教授 (90160829)
• Co-Investigator(Kenkyū-buntansha): 羽倉 尚人 東京都市大学, 理工学部, 准教授 (00710419)
• Project Period (FY): 2016-04-01 – 2020-03-31
• Keywords: ガン治療 / 化学療法 / 抗ガン剤 / 放射線分解 / Ｘ線吸収端 / 陽子線励起単色X線 / 加速器 / 高速液体クロマトグラフィー

Outline of Final Research Achievements

We investigated the feasibility of a cancer chemotherapy based on in-cell synthesis of anti-cancer drugs from non-toxic precursor compound by X-ray irradiation using a syringe-needle-type proton-induced monochromatic X-ray source inserted into the tumor. The dependence of the yield of decomposition products on the incident X-ray energy was measured using monochromatic X-rays with different energies around the absorption edge of the metallic element in the precursor material. As a result, it was confirmed that even if the absorbed dose was the same, the yield of some specific decomposition products was higher when the X-ray energy exceeded the absorption edge energy. From this result, we found that a minimally invasive treatment for synthesizing anticancer drugs only inside cancer cells is possible in principle, if an energy-optimized proton-induced monochromatic X-ray is used for irradiation of the precursor compound.

Free Research Field

イオンビーム応用工学

Academic Significance and Societal Importance of the Research Achievements

ガンの化学療法に伴う副作用を，低線量の放射線化学反応を用いて根本的に解決する方法を提案し，その原理的実証を行った．従来，放射線化学反応の収量は，物質へのエネルギー付与を基準に議論されてきたが，これに加えて物質を構成する元素の低エネルギー領域におけるX線吸収端構造を考慮して収量の光子エネルギー依存性に注目した．この手法に必要な高性能単色X線源の開発，線量の精密評価，動物実験等による検証，さらに適切な高選択性を持つ抗ガン剤前駆物質の開発が進めば，低線量のX線照射だけで無害の原料物質からガン細胞内部に限定して抗ガン剤を合成できるため，原理的には患者への負担が大幅に軽減される．