TET1 and breast cancer: Further support for TET proteins as regulators of oncogenic behavior was provided by engineered expression of microRNA (miR-22) which down-regulated expression of TET1,2,3, triggered epithelial-mesenchymal transition in the human MCF10 breast epithelial cell line and caused non-metastatic human MCF-7 breast cancer cell line to express metastatic properties: cell proliferation, invasion, and angiogenesis [158].