Identification of the sub-population in human malignant melanoma showing strong resistance to tumor specific cytotoxic T cells

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K09783
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Dermatology
• Research Institution: Keio University
• Principal Investigator: Yaguchi Tomonori 慶應義塾大学, 医学部(信濃町), 講師 (40424163)
• Co-Investigator(Kenkyū-buntansha): 河上 裕 慶應義塾大学, 医学部(信濃町), 教授 (50161287)
• Co-Investigator(Renkei-kenkyūsha): INOZUME Takashi 山梨大学, 医学部, 専任講師 (80334853)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 悪性黒色腫 / 免疫療法

Outline of Final Research Achievements

Although cancer immunotherapies have become one of the major treatment for malignant melanoma (MM), only 20-30% of patients can show objective clinical responses. Unresponsiveness to immunotherapies may be mediated by numerous immunosuppressive mechanisms that inhibit anti-tumor T-cell responses. Thus, combined therapies that can reverse immunosuppression in non-responders and identification of biomarkers for responders are urgently needed. In this study, we have identified three cell surface markers which could define particular subpopulation showing resistance to tumor antigen specific cytotoxic T cells. Moreover, by cDNA microarray analysis, we also identified the one responsible gene that directly caused this resistance. These results indicate that these cell surface markers and the gene may be potential biomarkers for the prediction of responders for immunotherapies and could be used as attractive therapeutic targets in MM.

Free Research Field

腫瘍免疫学