The BRAF Inhibitor Vemurafenib Activates Mitochondrial Metabolism and Inhibits Hyperpolarized Pyruvate-Lactate Exchange in BRAF-Mutant Human Melanoma Cells.
Date
2016-12-01Author
Delgado-Goni, T
Miniotis, MF
Wantuch, S
Parkes, HG
Marais, R
Workman, P
Leach, MO
Beloueche-Babari, M
Type
Journal Article
Metadata
Show full item recordAbstract
Understanding the impact of BRAF signaling inhibition in human melanoma on key disease mechanisms is important for developing biomarkers of therapeutic response and combination strategies to improve long-term disease control. This work investigates the downstream metabolic consequences of BRAF inhibition with vemurafenib, the molecular and biochemical processes that underpin them, their significance for antineoplastic activity, and potential as noninvasive imaging response biomarkers. 1H NMR spectroscopy showed that vemurafenib decreases the glycolytic activity of BRAF-mutant (WM266.4 and SKMEL28) but not BRAFWT (CHL-1 and D04) human melanoma cells. In WM266.4 cells, this was associated with increased acetate, glycine, and myo-inositol levels and decreased fatty acyl signals, while the bioenergetic status was maintained. 13C NMR metabolic flux analysis of treated WM266.4 cells revealed inhibition of de novo lactate synthesis and glucose utilization, associated with increased oxidative and anaplerotic pyruvate carboxylase mitochondrial metabolism and decreased lipid synthesis. This metabolic shift was associated with depletion of hexokinase 2, acyl-CoA dehydrogenase 9, 3-phosphoglycerate dehydrogenase, and monocarboxylate transporters (MCT) 1 and 4 in BRAF-mutant but not BRAFWT cells and, interestingly, decreased BRAF-mutant cell dependency on glucose and glutamine for growth. Further, the reduction in MCT1 expression observed led to inhibition of hyperpolarized 13C-pyruvate-lactate exchange, a parameter that is translatable to in vivo imaging studies, in live WM266.4 cells. In conclusion, our data provide new insights into the molecular and metabolic consequences of BRAF inhibition in BRAF-driven human melanoma cells that may have potential for combinatorial therapeutic targeting as well as noninvasive imaging of response. Mol Cancer Ther; 15(12); 2987-99. ©2016 AACR.
Collections
Subject
Cell Line, Tumor
Mitochondria
Humans
Melanoma
Sulfonamides
Lactates
Pyruvic Acid
Indoles
Pyruvate Carboxylase
Proto-Oncogene Proteins B-raf
Glucose
Antineoplastic Agents
Gene Expression Regulation, Enzymologic
Energy Metabolism
Mutation
Models, Biological
Metabolomics
Vemurafenib
Research team
Magnetic Resonance
Language
eng
Date accepted
2016-09-24
License start date
2016-12
Citation
Molecular cancer therapeutics, 2016, 15 (12), pp. 2987 - 2999
Publisher
AMER ASSOC CANCER RESEARCH