Cancer therapy by Cerenkov radiation

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K15568
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Radiation science
• Research Institution: Hokkaido University
• Principal Investigator: Ogawa Mikako 北海道大学, 薬学研究院, 教授 (20344351)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: Cerenkov

Outline of Final Research Achievements

It is difficult to deliver light to deep tissue in human, due to scatter and attenuation of the light. In this study, we aimed to treat cancer by photoimmunotherapy in deep tissue, using Cerenkov luminescence resonance energy transfer (CRET) by PET probe.
It was confirmed that cell death occurs in the same way as excitation of the Q band in the near infrared region by excitation of the Soret band of IR700 molecules that can be excited by Cerenkov light. However, no cell death was observed using 18F-labeled antibody or antibody fragment. Thus, we tried to use X-ray excitation / ionization, and activation of photoreactive compounds was successfully observed.

Free Research Field

Molecular imaging

Academic Significance and Societal Importance of the Research Achievements

PETやMRIなど他の分子イメージング法に比べ、蛍光イメージングは生体透過性が低いという欠点がある。本研究ではこの克服を試みた。今回、CRETによる治療までには至らなかったが、Cerenkov光により化合物が励起できることを示すことができた。18Fを用いたためβ線のエネルギーや半減期が十分でなかった可能性が高い。今後68Gaを用いて検討を進めることでCRETによる治療が達成されると考える。