MMP9 and breast cancer: We next examined the expression of the selected genes including Lrp5 (Wnt co-receptor), MMP2, MMP3, MMP9 (matrix metalloproteinases), Snail (inducer of epithelial-mesenchymal transition), Runx2, and TGFβ (bone-linked tumor promoters), as well as cleaved caspase 3 (apoptosis marker), in response to the selected regulatory proteins in EO771 mammary tumor cells.