Vascular permeability changes involved in tumor metastasis.

Cancer cell extravasation resembles the leukocyte recruitment during inflammation. Evidence suggests that cancer cells need to weaken the interendothelial junctions in order to cross the endothelial barrier. Several tumor-derived vasoactive compounds have been pointed out to drive this increase in vascular permeability: VEGF, Angptl4, CCL2, SDF-1, etc. Therefore, tumor cells have a wide repertoire of soluble factors to increase vascular permeability in order to colonize new tissues. Tumor soluble factors activate different signaling pathways to induce interendothelial junction disassembly, one common element is Src kinase. Here we summarize the relevant current knowledge about vascular permeability changes involved in tumor metastasis.