Why does alpha-ray therapy work? Approaching the question from the viewpoint of cancer immunity

2022 Fiscal Year Final Research Report

• Project/Area Number: 19K22587
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 52:General internal medicine and related fields
• Research Institution: Hokkaido University
• Principal Investigator: Ogawa Mikako 北海道大学, 薬学研究院, 教授 (20344351)
• Co-Investigator(Kenkyū-buntansha): 東川 桂 北海道大学, アイソトープ総合センター, 助教 (10756878)
• Project Period (FY): 2019-06-28 – 2022-03-31
• Keywords: α線 / 核医学治療 / がん免疫

Outline of Final Research Achievements

First, we examined cancer immunity induced by external irradiation with X-rays. The results suggest that external irradiation with X-rays temporarily reduces the activation of immunity in tumors, but subsequently induces the activation of cancer immunity. We synthesized At-211-labeled RGD peptides and examined cell death. We have previously shown that the At-211-labeled peptide releases more calreticulin upon immune activation than the I-131-labeled peptide. On the other hand, no correlation was observed between the amount of At-211 labeled material taken into cells and the amount of Calreticulin released. This may suggest that the At-211-labeled drug taken into the cell is not highly effective in disrupting the cell membrane.

Free Research Field

分子イメージング

Academic Significance and Societal Importance of the Research Achievements

α線核医学治療への期待が世界的に高まっている。これは、臨床で見られた治療効果の高さによるが、その理由がわかっていない。本研究では、がん免疫に着目しα線の治療効果について検証し、免疫賦活化の可能性を示した。さらに、At-211による標識薬剤の合成に成功し、今後のα線核医学治療の展開へ向けて一助になるものと考える。