2013 Fiscal Year Final Research Report

The role of macrophage polarization in recurrence of oral cancer

Research Project

Project/Area Number	23592971
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Surgical dentistry
Research Institution	Yokohama City University
Principal Investigator	KIOI Mitomu 横浜市立大学, 医学部, 准教授 (30545059)
Project Period (FY)	2011 – 2013
Keywords	がん微小環境
Research Abstract	Radiotherapy and chemotherapy play a major role in the treatment of oral cancer as conservative therapy. However, tumors recur or grow after those treatment in many cases. In this study, we investigated if the irradiation and chemo drug affect the tumor vasculature using human oral cancer clinical samples and xenograft mouse model. We found higher levels of CD11b+cells in recurrent tumors compared with those in the untreated primary tumors. Next, we performed sub-class analysis of CD11b+ monocytes that were recruited into tumor following irradiation using OSC-19 bearing mice. Tumors were collected at different time points after irradiation. Highest number of CD11b+cells was recruited into tumors in two weeks after irradiation, and many of them showed co-expression of Tie2, which is thought as proangiogenic TIE2-expressing macrophages (TEMs). The data suggest that recruited TEMs are deeply involved in tumor recurrence after anti-cancer treatment.