Recent reports have demonstrated that NF-κB indirectly inhibits ROS generation (Sakon et al, 2003; Kamata et al, 2005); however, the intracellular ROS balance may be regulated by multiple pathways, therefore, it is still uncertain whether ROS generation is due to NF-κB/I-κB inhibition cascade in bortezomib-treated cancer cells. Here, NFKB1 is linked to cancer.