It has recently been reported that TGF-β increases NOX4 gene expression by Smad3-dependent mechanism and that Nox4 contributes to ROS production which may be critical for the progression of the TGF-β-induced EMT in breast cancer and moreover indicates the role of Nox4 in the enhancement of cell motility, without affecting cell proliferation [52]. This evidence concerns the gene SMAD3 and breast carcinoma.