TGF-β triggers ROS production in lung cancer cells through the NF-κB-dependent induction of NADPH oxidase 4 (NOX4) expression [93,94] Interestingly, in vitro studies suggest that this pathway is required for the induction of EMT by TGF-β, as pharmacological inhibition of NOX4 or NF-κB suppresses ROS production and reverses changes in motility and EMT markers in A549 cells [93,94]. This evidence concerns the gene NOX4 and lung cancer.