MMP2 and melanoma: For example, BBR inhibits MMP-2 and MMP-9 expression by downregulating TGF- β1 and the COX-2/PGE2–JAK2/STAT3 axis in breast cancer [122,123], and epithelial-mesenchymal transition in melanoma by inhibition of the RARα/β-mediated PI3K/AKT signaling pathway [124].