In support of our early in vitro findings that NOX4 is involved in cancer progression and migration, Zhang et al., showed Nox4 silencing by shRNA decreased the TGF-β-induced migration of 4T1 murine breast cancer cells and significantly attenuated 4T1 cells metastasis to the lungs and bones of nude mice [15]. This evidence concerns the gene NOX4 and breast carcinoma.