A modified Boyden chamber assay for tumor cell transendothelial migration in vitro.

We have developed a modified Boyden chamber system for assessing tumor cell transmigration across endothelial monolayer in vitro. This radiometric-based method allows us to take into account the cells which have traversed but detached from the filter, a significant fraction not included in the existing method of visual counting. The method was applied to examine six malignant and one non-malignant cell lines. The variable invasive potentials of these cells were found to correlate with their ability to disrupt the endothelial cell monolayers.