We applied an explorative, untargeted metabolomics approach with liquid chromatography/tandem mass spectrometry (LC-MS/MS) to characterize the largest possible number of metabolites from relevant or potentially affected metabolic pathways in isogenic NSCLC cells overexpressing mutated forms of KRAS at codon-12 (G12C, G12D, G12V). The gene discussed is KRAS; the disease is non-small cell lung carcinoma.