Figure 3

Microglial stimulation of glioma invasion depends on CSF-1R signaling. (A) Western blot showing the effect of the indicated concentrations of CSF-1R inhibitor on CSF-1-stimulated CSF-1R (Y723) and ERK phosphorylation levels. Result is representative of three independent experiments. (B) Invasion of GL261 cells alone (open bar) or with microglia (closed bars) in the presence of DMSO, 10 nmol/L JnJ, 1 µmol/L PLX3397 or 1 µmol/L PLX5622. Means ± SEM of data from six independent experiments. *P < 0.01 compared with +MG control. (C, D) Growth of either GL261 (C) or microglia (D) cultured under invasion assay conditions in DMSO, 10 nmol/L JnJ, 1 µmol/L PLX3397 or 1 µmol/L PLX5622. Results are normalized to the SRB measurement of cells on the day of drug addition. Means ± SEM of data from three independent experiments. (E) Western blot showing the extent of CSF-1R knockdown by siRNA. Blot shown is representative of three experiments. (F) Invasion of GL261 cells alone (open bar) or with microglia (closed bars) transfected with control siRNA or siRNA targeting CSF-1R. Means ± SEM of data from four experiments. *P < 0.05 compared with +MG control siRNA.