T98G, U251 and SNB19 glioma cells transiently transfected with two independent siRNAs against human CTGF (C1, C2) or luciferase show decreased protein levels in siRNA treated cells (A). CTGF knock-down results in decreased cell migration. Migration rate is expressed relative to luciferase (Control) treated samples (A). Cell invasion in organotypic rat brain slices; SNB19 and U251 glioma cells stably expressing GFP were transfected with siRNA directed against luciferase (control) or CTGF (C1, C2); z-axis invasion was assessed by confocal microscopy. Results are normalized to control-treated cells and all experiments were performed at least three times (C); Bars, SE; (*, p < 0.05; **, p < 0.001).