TGFB1 and neoplasm: This suggested that tumor cells that undergo TGF-β1-induced EMT gain the capacity to migrate toward CCR7 ligands, such as CCL21, which is known to be produced by lymphatic endothelial cells and to promote migration of DCs toward lymphatic vessels.24 To test this, we performed invasion assays, in which cells with different EMT properties were seeded in the upper wells and recombinant CCL21 (350 ng/ml), or 10% fetal calf serum, was added in the lower chamber as a chemoattractant.