Fig. 3
Effects of MMP-9 gene expression silencing on h-TGF-β1-induced KKU-M213 cell invasion. Cells were transfected with 15 nM siMMP-9 or non-targeting siRNA (siNeg) for 24 h followed by treatment with or without 5 ng/mL h-TGF-β1 for 24 h in 0.1% FBS media. Control experiment was performed using non-transfected cells. Silencing efficiency was evaluated from the reduction in band intensity of MMP-9 from gelatin zymogram (a). For in vitro invasion assay, cells (105) were plated onto Matrigel-coated Transwell chamber and incubated for 6 h. Numbers of invaded cells were stained with 5% crystal violet and counted (b). Data are presented as mean ± SEM of percent band intensity (a) or percent invaded cells (b) relative to h-TGF-β1-treated control from at least three independent experiments. **P < 0.001