INTRODUCTION: KRAS was one of the earliest human oncogenes to be described and 
is one of the most commonly mutated genes in different human cancers, including 
colorectal cancer. Despite KRAS mutants being known driver mutations, KRAS has 
proved difficult to target therapeutically, necessitating a comprehensive 
understanding of the molecular mechanisms underlying KRAS-driven cellular 
transformation.
OBJECTIVES: To investigate the metabolic signatures associated with single copy 
mutant KRAS in isogenic human colorectal cancer cells and to determine what 
metabolic pathways are affected.
METHODS: Using NMR-based metabonomics, we compared wildtype (WT)-KRAS and mutant 
KRAS effects on cancer cell metabolism using metabolic profiling of the parental 
KRAS G13D/+ HCT116 cell line and its isogenic, derivative cell lines KRAS +/- 
and KRAS G13D/-.
RESULTS: Mutation in the KRAS oncogene leads to a general metabolic remodelling 
to sustain growth and counter stress, including alterations in the metabolism of 
amino acids and enhanced glutathione biosynthesis. Additionally, we show that 
KRASG13D/+ and KRASG13D/- cells have a distinct metabolic profile characterized 
by dysregulation of TCA cycle, up-regulation of glycolysis and glutathione 
metabolism pathway as well as increased glutamine uptake and acetate 
utilization.
CONCLUSIONS: Our study showed the effect of a single point mutation in one KRAS 
allele and KRAS allele loss in an isogenic genetic background, hence avoiding 
confounding genetic factors. Metabolic differences among different KRAS 
mutations might play a role in their different responses to anticancer 
treatments and hence could be exploited as novel metabolic vulnerabilities to 
develop more effective therapies against oncogenic KRAS.