CCL2 upregulation by S100B. A, In vitro CCL2 (but not CXCL12) secretion and B, expression (red staining) was significantly higher in S100Bwt and S100Bhigh GL261 cells (n=3/group, ±SD, * : p < 0.05). C, In vivo CCL2 expression was also upregulated in two-week old i.c. S100Bwt and S100Bhigh tumors (T). Results are representative of two separate experiments.