Anti-tumor effect of myeloid derived suppressor cell(MDSC) in a mouse model of oral cancer

In the present study, we conducted immunological study for myeloid derived suppressor cell(MDSC)in a mouse oral cancer model. We investigated whether in vivo administration of chemotherapetuic agent affected the distributions of immune cells, tumor-cell surface expression levels of immune accessory molecules and T cell immune responses in tumor-bearing mice.In vivo administration of chemotherapeutic agent induced significant oral cancer-cell apoptosis in vitro, and chemotherapy markedly attenuated established mouse tumor growth. Chemotherapy decreased the numbers of both myeloid-derived suppressor cells (MDSCs) and B cells in tumor-bearing mice and enhanced dendritic cell maturation. Moreover,chemotherapy upregulated tumor-cell surface expressions of several immune accessory molecules and adhesion molecules, including CD80, CD86, CD40, ICAM-1, VCAM-1, and P-selectin. Remarkably, these tumor cells augmented tumor specific T-cell responses.