Prognostic Prediction and Therapeutic Application Focusing on the Oral Environment in Pancreatic Cancer Patients

2024 Fiscal Year Final Research Report

• Project/Area Number: 22K08694
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 55010:General surgery and pediatric surgery-related
• Research Institution: Kyushu University
• Principal Investigator: SADAKARI Yoshihiko 九州大学, 医学研究院, 共同研究員 (80784503)
• Co-Investigator(Kenkyū-buntansha): 森山 大樹 九州大学, 医学研究院, 共同研究員 (70586859) ; 田村 公二 九州大学, 大学病院, 助教 (90909582)
• Project Period (FY): 2022-04-01 – 2025-03-31
• Keywords: 膵癌 / 口腔内環境 / 歯周病原細菌 / 腫瘍微小環境 / 治療抵抗性

Outline of Final Research Achievements

We demonstrated that one of the causative bacteria of periodontitis (XX) promotes the secretion of cytokines that induce immunosuppressive cells both in vitro and in vivo, contributing to tumor growth and a reduction in tumor-infiltrating T cells. Furthermore, we revealed that oral hygiene status correlates with the amount of intratumoral bacteria and resistance to chemotherapy. As part of the underlying mechanism, we confirmed in a mouse pancreatic cancer model that the periodontopathic bacterium XX alters the phenotype and function of a certain immune cell population, and that this bacterium increases resistance to chemotherapy.

Free Research Field

医歯薬学

Academic Significance and Societal Importance of the Research Achievements

これらの研究成果は、歯周病原細菌が何らかのかたちで腫瘍内にとどく可能性を示唆するものであり、また歯周病原細菌により免疫抑制性微小環境が構築されること、また治療への抵抗性を増強させることを示すものであり、新たな治療標的の発見や膵癌治療全体における口腔ケアの重要性を示唆する大きな成果であるといえる。