Tumor Metabolism Keystone Meeting
The Keystone Symposia Meeting on Tumor Metabolism is a reference conference for the field. Here experts are discussing the latest research and new emerging concepts in cancer metabolism regulation and its role in tumor growth. At this conference, researchers from the University of Oxford will be presenting a poster entitled: “Modelling tumor hypoxia through parallel analysis of cellular oxygenation, glycolysis flux and mitochondrial function” (Poster #2077). The poster displays data generated in conjunction with the MetaCell Project.
The poster describes a methodology for modeling tumor hypoxia in vitro using the MitoXpress® Intra Intracellular Oxygen Assay probe measured on the CLARIOstar microplate reader equipped with Atmospheric Control Unit. The data presented invalidate the assumption that cellular oxygenation can be inferred from ambient O2 measurements. It moreover illustrates how this assumption can lead to erroneous conclusions regarding the relationship between O2 concentration, HIF stabilization and related metabolic adaptations.
Modelling tumour hypoxia through parallel analysis of cellular oxygenation, glycolysis flux and mitochondrial function.
M. Potter1, M. Schwalfenberg2, C. Yalaz1, R. McGarrigle2, C. Zois1, A. Harris1, J. Hynes2, K Morten1
1University of Oxford, Oxford, UK, 2Luxcel Biosciences, Cork, Ireland
Malignant transformation is associated with significant metabolic reprogramming, as cancer cells strive to maintain ATP supply and fuel catabolism, often achieved by increasing glycolytic flux. A key factor influencing this metabolic programming is oxygen availability. This is particularly true of solid tumours, where oncogene-driven proliferation causes nutrient and oxygen deprivation, aberrant angiogenesis, and the activation of such O2-sensitive survival pathways. Delineating the relationship between oxygenation and such metabolic reprogramming is therefore key to a deeper understanding of these processes and to the development of more effective therapeutic interventions. Detailed in vitro analysis has however been limited due to the absence of methodologies capable of controlling and monitoring cellular oxygenation, while in parallel, probing other key parameters such as glycolytic flux and HIF stabilisation. Here we describe a methodology for modelling tumour hypoxia in vitro using a fluorescence plate reader equipped with an atmospheric control unit (CLARIOstar) in combination with a nanoparticulate intracellular oxygen probe (MitoXpress-Intra). Data is presented illustrating that the depth of hypoxia experienced by the cell model is impacted significantly by respiratory activity, and that this additional oxygen deprivation is a dynamic process, effected by respiratory substrate availability and related metabolic poise. Multiplexing with the pH-sensitive probe (pH-Xtra™) allows real-time monitoring of cellular oxygenation and glycolytic activity allowing the interrelationship between oxygenation and glycolytic flux to be characterised. Together these data invalidate the assumption that cellular oxygenation can be inferred from ambient oxygen measurements and if ignored, the significant and dynamic deviations between ambient O2 and oxygenation at the cellular level lead to erroneous conclusions regarding the relationship between oxygen concentration, HIF stabilisation and related metabolic adaptations. This, in turn, can impair the physiological relevance of experimental observations.