Figure 7.
Invasion assay of ErbB-2-overexpressing LNCaP cells with or without matriptase knockdown. Matriptase knockdown was performed as described in Figure 6A. For cell invasion assays, each filter insert was coated with 30 μg/cm2 matrigel. After trypsinization, 1 × 105 cells were seeded with serum-free RPMI 1640 medium in each insert chamber, and lower chambers were filled with 10% FBS RPMI 1640 medium. A: Transwell invasion assays were carried out for 48 hours. Invasive cells were fixed in methanol and stained with 1% crystal violet. Images were captured by a light microscopy (original magnification, ×100). B: Numbers of invasive cells on each filter were counted from eight random fields (original magnification, ×200). Each assay was performed in triplicate for calculation of means ± SE; statistically significant differences, *P < 0.05 were observed between Vec/shLuc and ErbB-2/shLuc, as well as ErbB-2/shLuc and ErbB-2/shMTX.