NFKB1 and lung cancer: Furthermore, when KRAS or IKKβ expression was reduced by transfecting human lung cancer cell lines with siRNA targeting either KRAS or IKKβ, NF-κB luciferase reporter activity was also inhibited, indicating that, in these cells, both KRAS and IKKβ are promoting NF-κB activity (Supplementary Fig. S1).