Clarification of tumor immune system in chemical carcinogenic autoimmune model mice

Research Project

Project/Area Number	17K17964
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Multi-year Fund
Research Field	Morphological basic dentistry Pathobiological dentistry/Dental radiology
Research Institution	Kagoshima University
Principal Investigator	Kondo Tomoyuki 鹿児島大学, 医歯学域歯学系, 助教 (10782873)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000) Fiscal Year 2019: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2017: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Keywords	腫瘍免疫 / 自己免疫 / 化学発がん / 腫瘍
Outline of Final Research Achievements	We analyzed Azoxymethane-induced colorectal cancer model in autoimmune B6/lpr mice to clarify the basic tumor immune response in autoimmune disease. As a result, both autoimmune model mice and control mice showed colorectal adenocarcinomas, but only autoimmune model mice showed cancer nests involved in the submucosal layer beyond the muscularis mucosa. Furthermore, the immune cell populations in peripheral blood samples were analyzed by flow cytometry. The proportions of PD-1+ T cells and CTLA4+ B cells in autoimmune model mice were significantly higher compared with that in control mice. These results suggest that tumor immunity was suppressed in autoimmune model mice.
Academic Significance and Societal Importance of the Research Achievements	現在腫瘍に対する免疫システムは現在大きく着目され、いわゆる免疫療法が脚光を浴び一部は臨床応用されている。しかしながらある一定の治療効果は認められているものの、根治的な治療法としては課題が多くさらなるブレイクスルーが世界的に求められている。本研究は腫瘍免疫を自己免疫と絡めた独特の視点から解析したもので、本研究で得られた結果は腫瘍免疫に対する新たな知見である。今後さらに本研究内容を発展させれば腫瘍免疫療法のブレイクスルーに繋がる可能性がある。