To clarify whether NRF2 has any active role in promoting tumor-initiating activity, which is one of the important properties for aggressive tumorigenesis (Supplementary Fig. 1a, b), we cultured three NRF2-activated NSCLC cell lines with KEAP1 mutations, A549, H460 and H202330, under low attachment conditions in defined stem cell medium to allow them to grow in the form of oncospheres31. This evidence concerns the gene KEAP1 and non-small cell lung carcinoma.