CUX1 and cancer: CUX1 knockdown does not impair the clonogenic efficiency of cancer cell lines that exhibit low ROS levels but is synthetic lethal in all cancer cells that display elevated ROS levels, whether this results from an activating mutation in a RAS gene (Hs578THRAS, MDA-MB-231KRAS, DLD-1KRAS, HCT116KRAS, KE37NRAS), another gene in the pathway (HT29BRAF), or an upstream receptor tyrosine kinase (HCC827EGFR)[100,113].