Study of the effect of Immune Checkpoint Inhibitor

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K10291
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 57060:Surgical dentistry-related
• Research Institution: Nagasaki University
• Principal Investigator: kawasaki goro 長崎大学, 医歯薬学総合研究科(歯学系), 准教授 (60195071)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 口腔癌 / 扁平上皮癌 / PD-L1 / PD-L2 / PD-1

Outline of Final Research Achievements

PD-L1 and PD-L2 were immunohistochemically expressed in oral cancer patients. The cases of both expressions have correlation with invasion and growth of the cancer cells, therefor it was suggested that both expressions of PD-L1 and PD-L2 has a correlation with abnormality of tumor cells. In oral cancer cell lines, PD-L1 and PD-L2 were expressed, and there was significant difference with cancer cell invasion and cell growth. In blockade cell line of PD-L1 and PD-L2, the abilities of invasion and cell growth of the cancer cells were degreased. In some of the cell lines, PD-L1 and PD-L2 was admitted without effect of PD-1, and it was suggested to be concerned the degree of malignancy. Both expressions of PD-L1 and PD-L2 tended to affect the effect of chemotherapeutic agent to the cancer cells.

Free Research Field

口腔外科学

Academic Significance and Societal Importance of the Research Achievements

一般に癌細胞においてPD-1によりPD-L1が誘導されることで癌細胞抑制がおこることから、PD-L1が発現している細胞の方が抗PD-1抗体を用いた治療に有効とされている。しかしながら、本研究結果からリンパ球に誘導されないで腫瘍細胞自体に独自に発現するPD-L1とPD-L2が認められ、それらが腫瘍の悪性度や治療抵抗性に関与している可能性が示唆された。口腔癌における抗PD-1抗体療法に抵抗性がある場合には、これらの抗体を調べ、予後の予測をすることや、抗体療法を含めた治療法を考えることが必要とされる研究結果となった。