Cancer vaccines targeting tumor blood vessels in GIST

2015 Fiscal Year Final Research Report

• Project/Area Number: 25460936
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Gastroenterology
• Research Institution: Jikei University School of Medicine
• Principal Investigator: KOMITA HIDEO 東京慈恵会医科大学, 医学部, 講師 (90534561)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: GIST / 免疫チェックポイント分子 / Tim-3 / Galectin-9 / NK細胞 / immunetherapy

Outline of Final Research Achievements

We have previously reported that human gastrointestinal stromal tumor (GIST)has immunogenic features but the antitumor immunity to GIST seems to be suppressed in vivo. In the present study, immune cell types infiltrated into the 19 GIST tissues and immune checkpoint molecules were identified by immunehistochemistry. All the GIST tissues were from local gastric lesions and obtained by the surgical procedure. Nineteen and 8 GIST tissues showed CD8+ T cell and CD56+ natural killer (NK) cell infiltration, respectively, and their infiltrations were strongly correlated. T cell immunoglobulin and mucin protein 3(Tim-3) expression was seen in 6/8 (75%) of NK cells. Galectin-9 expression was observed in 13/19 (68.4%) of GIST tissues, and all the GIST tissues with Tim-3+NK cell infiltration showed positive galectin-9 expression. Tim-3/galectin-9 interaction between NK cells and GIST tumor cells might be involved in the suppression of antitumor immunity in GIST.

Free Research Field

腫瘍免疫学