Biocoat matrigel invasion chambers for 24 well plates

The invasive ability of each cell line was assessed using BD BioCoatMatrigel Invasion Chambers for 24-well plates (BD Bioscience, Franklin Lakes, NJ, USA), according to the manufacturer’s instructions. In brief, Matrigel on the polycarbonate membrane with 8 μm pore was rehydrated using 750 μL of serum-free medium, after which 750 μL of fresh medium containing 10% FBS as chemoattractant was added to the lower chamber. Next, 0.5 mL of each cell line (1 × 10⁵ cells/mL) in serum-free medium was seeded into the upper chamber. After 24 h, cells in the upper chamber were removed, and those that had invaded through the Matrigel were fixed in 100% methanol and stained with hematoxylin. Using three membranes per group, invading cells were counted in several fields under a microscope with a 10 × objective. The following equation was used to calculate the proportion of invading cells: % invasion = (mean number of cells invading through Matrigel/mean number of cells migrating through Matrigel-uncoated polycarbonate membrane) × 100.