TGFB1 and breast cancer: One study suggested that this switch occurs due to other proteins, such as 14-3-3ζ.17 In a different study, it was shown that TGFβ, which is produced abundantly by stromal cells, stimulates the expression of ANGPTL4, which itself disrupts the capillary vascular endothelial cell junctions and enables dissemination of breast cancer cells to initiate lung metastasis.18 Identifying novel regulators of Wnt and TGFβ signaling pathways would greatly enhance our understanding and management of metastasis.