The mechanism of synergistic effects of combination therapy with PDT and immune checkpoint inhibitors

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K08361
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 53010:Gastroenterology-related
• Research Institution: Nagoya City University
• Principal Investigator: Tanaka Mamoru 名古屋市立大学, 医薬学総合研究院(医学), 助教 (80617861)
• Co-Investigator(Kenkyū-buntansha): 片岡 洋望 名古屋市立大学, 医薬学総合研究院(医学), 教授 (40381785)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: PDT / ICD / DAMPs / PD-1

Outline of Final Research Achievements

Photodynamic therapy (PDT) is a minimally invasive therapy that selectively destroys tumor cells by irradiating laser light onto tumor tissue where light-sensitive substances have selectively accumulated. Immune checkpoint inhibitors show sustained tumor shrinkage, but the response rate is limited.
We found that PDT induces immunogenic cell death (ICD) and activates anti-tumor immunity via the release of Damage-associated molecular patterns (DAMPs). radiation therapy (RT), and synergistic effects of combination therapy with immune checkpoint inhibitors are highly expected.
In this study, we aim to elucidate the basic mechanism of the synergistic effect of combination therapy with PDT and immune checkpoint inhibitors, focusing on the release of DAMPs and changes in the tumor environment, and to establish a therapeutic strategy to overcome resistance and tolerance to immune checkpoint inhibitors, which is a future challenge.

Free Research Field

消化器内科

Academic Significance and Societal Importance of the Research Achievements

PDTとICIそれぞれは現在すでに臨床応用をされており、さらに現在併用の臨床試験を施行しており、これにより効果が確認され今後標準治療となることが期待されている。今回の検討結果はその動機付けの一つになったかと考えている。