title: Oncogenic K-Ras decouples glucose and glutamine metabolism to support cancer cell growth.
abstract: Oncogenes such as K-ras mediate cellular and metabolic transformation during tumorigenesis. To analyze K-Ras-dependent metabolic alterations, we employed ¹³C metabolic flux analysis (MFA), non-targeted tracer fate detection (NTFD) of ¹⁵N-labeled glutamine, and transcriptomic profiling in mouse fibroblast and human carcinoma cell lines. Stable isotope-labeled glucose and glutamine tracers and computational determination of intracellular fluxes indicated that cells expressing oncogenic K-Ras exhibited enhanced glycolytic activity, decreased oxidative flux through the tricarboxylic acid (TCA) cycle, and increased utilization of glutamine for anabolic synthesis. Surprisingly, a non-canonical labeling of TCA cycle-associated metabolites was detected in both transformed cell lines. Transcriptional profiling detected elevated expression of several genes associated with glycolysis, glutamine metabolism, and nucleotide biosynthesis upon transformation with oncogenic K-Ras. Chemical perturbation of enzymes along these pathways further supports the decoupling of glycolysis and TCA metabolism, with glutamine supplying increased carbon to drive the TCA cycle. These results provide evidence for a role of oncogenic K-Ras in the metabolic reprogramming of cancer cells.
authors.affiliation: Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Gaglio
authors.forename: Christian M
authors.initials: CM
authors.lastname: Metallo
authors.forename: Paulo A
authors.initials: PA
authors.lastname: Gameiro
authors.forename: Karsten
authors.initials: K
authors.lastname: Hiller
authors.forename: Lara Sala
authors.initials: LS
authors.lastname: Danna
authors.forename: Chiara
authors.initials: C
authors.lastname: Balestrieri
authors.forename: Lilia
authors.initials: L
authors.lastname: Alberghina
authors.forename: Gregory
authors.initials: G
authors.lastname: Stephanopoulos
authors.forename: Ferdinando
authors.initials: F
authors.lastname: Chiaradonna
mesh_terms: D000818:Animals; D002461:Cell Line, Transformed; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000235:genetics / Q000378:metabolism*; D002952:Citric Acid Cycle; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D005434:Flow Cytometry; D008401:Gas Chromatography-Mass Spectrometry; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D005947:Glucose / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism*; D006019:Glycolysis; D006801:Humans; D007553:Isotope Labeling; D051379:Mice; D041681:NIH 3T3 Cells; D009369:Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D020411:Oligonucleotide Array Sequence Analysis; D016283:Proto-Oncogene Proteins p21(ras) / Q000235:genetics / Q000378:metabolism
chemical_list: D005973:Glutamine; D016283:Proto-Oncogene Proteins p21(ras); D005947:Glucose