Abstract B28: Multiplexed mass spectrometry analysis of KRAS-associated metabolic reprogramming in colorectal tumors and cell lines

Abstract

Abstract Mutational activation of KRAS is associated with increased cellular proliferation and tumorigenicity, and metabolic reprogramming. We have used a mass spectrometry analysis by multiple reaction monitoring (MRM) to quantify the expression of 62 proteins encompassing glycolysis (21 proteins), TCA cycle (14 proteins), pentose phosphate pathway (10 proteins), serine biosynthesis (4 proteins), and 13 other proteins involved in metabolism. We applied this MRM panel to the colon tumor cell line DLD-1 (one mutant (G13D) KRAS allele and one WT allele) and the isogenic derivative cell lines DKO-1 (G13D, -) and DKs-8 (+,-). DLD-1 and DKO-1 cells produce lactate at a significantly higher rate than the Dks-8 cells, indicating metabolic reprogramming reflecting a “Warburg” phenotype. MRM panel comparisons of these cell lines revealed that KRAS mutation was associated with the increased expression of glucose and glutamine transporters, glycolytic enzymes, enzymes involved in serine biosynthesis, and a few TCA cycle enzymes. Comparison of the isogenic KRAS mutant/WT pair to each other and to the DLD-1 parental cell line revealed distinct expression changes for the three different KRAS mutant/WT combinations, which suggests that mutant and WT KRAS play distinct roles in metabolic reprogramming. The MRM panel was also used to analyze 16 human formalin-fixed, paraffin-embedded (FFPE) Stage II colorectal tumors. Although the expression of the metabolic proteins varied from patient to patient, a consensus group of 7 metabolic proteins, including enzymes of glycolysis, were significantly increased in KRAS mutant tumors. These results demonstrate that mutational activation of KRAS induces metabolic reprogramming via signaling through both BRAF and PI3K signaling pathways in colorectal cancer cells by the altered expression of metabolic proteins. (Supported by NIH Grant U24CA159988) Citation Format: Josiah E. Hutton, III, Lisa J. Zimmerman, Robbert J. Slebos, Ming Li, Daniel C. Liebler. Multiplexed mass spectrometry analysis of KRAS-associated metabolic reprogramming in colorectal tumors and cell lines. [abstract]. In: Proceedings of the AACR Special Conference on RAS Oncogenes: From Biology to Therapy; Feb 24-27, 2014; Lake Buena Vista, FL. Philadelphia (PA): AACR; Mol Cancer Res 2014;12(12 Suppl):Abstract nr B28. doi: 10.1158/1557-3125.RASONC14-B28