NOX1-derived ROS are crucial for the regulation of metastasis through the toll-like receptor 4 (TLR4) in non-small lung cancer cells (NSCLC) [84], and it is possible that TLR4 signaling enhances the expression of NOX1 which subsequently regulates MMP-9 and increases metastasis in these cells [84, 85]. Here, TLR4 is linked to non-small cell lung carcinoma.