To determine the effects of the c-Met/β1 complex on intravasation of breast cancer cells, we developed a cell culture model of intravasation in which breast cancer cells were seeded in Transwell chambers and allowed to sequentially traverse Matrigel and a human umbilical vein endothelial cell (HUVEC) monolayer to model entrance into circulation (Figure 2A). This evidence concerns the gene MET and breast carcinoma.