Matrigel coated polycarbonate filters

Cells were seeded onto the upper surfaces of Matrigel-coated polycarbonate filters (BD Biosciences) in a modified Boyden chamber (Corning), and analyzed for their invasiveness as described previously [8 (link)].

These assays were performed as described previously [8 (link)]. Tumor cell invasion was measured by examined cells (2 × 10⁵) in 100 μl of medium were seeded onto the upper surfaces of Matrigel-coated polycarbonate filters which were coating with ECM components (BD Bioscience, Bedford, MA). These inserts were then placed in modified Boyden chambers (Corning, Corning, NY) and the lower compartment was filled with 1 ml of serum-free media containing with 0.1% bovine serum albumin. After 18 hrs of incubation at 37°C incubator, the migrated cells move to the lower surface of the filter, these cells were fixed, stained using Diff-Quick Kit (Fisher Scientific, Pittsburgh, PA), dried well and counted under a light microscope (Mitoti AE31 series, Trinocular inverted MIC) [10 (link)].