NF-κB inhibits mitochondrial permeability transition by inducing the expression of anti-apoptotic genes such as xIAP and Bcl-2 [37]. In addition, it also can promote the expression of MMP-9 and VEGF to promote tumor proliferation and migration [38]. Many studies have confirmed that chemotherapy drugs can inhibit NF-κB pathway [36, 39]. As secondary messengers, ROS is involved in the NF-κB pathway and plays a crucial role in apoptosis signaling pathways in many cancers [40]. This evidence concerns the gene MMP9 and cancer.