PTK2 and cancer: Soluble factors such as heparanase stimulates VEGF-C expression in cancer [441, 442], while TGFBI induces activation of FAK signaling pathway in lymphatic endothelial cells (LECs), and increased expression of CCL21 on the surface of LECs to induce the dissociation of VE-cadherin junctions between LECs [443, 444].