ANGPTL4 and breast cancer: For breast cancer, ectopic secretion of MMPs family, such as MMP-1, MMP-2 and MMP-9, as well as VEGF, angiopoietin-like-4 (Angptl4), and COX-2, could degrade and destroy vascular endothelial cell junctions to promote tumor cells metastasis [12, 13].