2011 Fiscal Year Final Research Report

Development of new therapy to activate anti-tumor immunity against head and neck squamous cell carcinoma

Research Project

Project/Area Number	22791569
Research Category	Grant-in-Aid for Young Scientists (B)
Allocation Type	Single-year Grants
Research Field	Otorhinolaryngology
Research Institution	Chiba University
Principal Investigator	SAKURAI Daiju 千葉大学, 大学院・医学研究院, 講師 (10375636)
Project Period (FY)	2010 – 2011
Keywords	頭頸部癌 / 腫瘍免疫 / 免疫抑制
Research Abstract	In this research, we performed exploratory studies of MDSC (myeloid-derived suppressor cells) in patients with head and neck cancer. MDSC in PBMC (peripheral blood mononuclear cells) fraction increased significantly in patients with head and neck squamous cell carcinoma (HNSCC) than that in healthy control. When CD15(+) MDSC was depleted from PBMC fraction, T-cell activation was enhanced. The proportion of MDSC in PBMC was negatively correlated with the proportion of lymphocytes in white blood cells. Especially, the negative correlation was found between the proportion of MDSC in PBMC and the proportion of T-cell in PBMC. Therefore it is suggested that MDSC suppress antitumor immunity by accumulation in patients with head and neck cancer and by decreasing T-cell number and suppressing T-cell activation. Development of therapies targeted to MDSC is thought to be a possible new strategy to activate antitumor immunity in patients with head and neck cancer.