FIGURE 5.

β1-Integrin mediates Snail-driven three-dimensional scattering and collagen-driven motility. AsPC1-vector, AsPC1-Snail, and AsPC1-Slug cells were induced with doxycycline (2 μg/ml) for 24 h, trypsinized, and incubated with a function-blocking β1-integrin antibody (P4C10) or isotype-matched control IgG antibody for 30 min. A and B, the cells were then suspended in three-dimensional collagen gel (2 mg/ml), and fresh serum-containing medium supplemented with doxycycline and β1-integrin-blocking antibody or control antibody was added every 2 days for 4 days. The effect on colony morphology was examined by phase contrast microscopy (A), and the percentage of scattered colonies per field was quantified (B). C and D, cells were also plated onto thin-layer type I collagen matrix overlaid with colloidal gold and allowed to migrate for 24 h, and the tracks were photographed (C) and quantified (D). Error bars in B and D indicate S.E. The results are representative of at least four independent experiments. *, p < 0.05.