Poster Presentation 35th Lorne Cancer Conference 2023

In vivo characterisation of melanoma metabolism in patients through perioperative [U-13C]glucose infusions. (#310)

Aparna D Rao 1 2 , Jennifer Gill 3 , Danika Player 4 , Britny Tillman 4 , John Huth 4 , Jade Homsi 4 , Travis Vandergriff 3 , David Gyorki 5 , Bernhard Riedel 5 , Ramin Alipour 5 , Christopher Angel 5 , Friyana Bhabha 5 , Shahneen Sandhu 6 , Grant McArthur 1 , Ralph DeBerardinis 4
  1. Molecular Oncology Laboratory, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
  2. Sir Peter MacCallum Department of Oncology, University of Melbourne, Parkville, VIC, Australia
  3. Dermatology, University of Texas Southwestern Medical Center, Dallas, Texas, USA
  4. University of Texas Southwestern Medical Center, Dallas, Texas, US
  5. Peter MacCallum Cancer Centre, Melbourne, VIC, Australia
  6. Division of Cancer Medicine, Peter MacCallum Cancer Centre, Melbourne, VIC, Australia

Reprogrammed metabolism is a hallmark of cancer cells which must meet high demands for energy formation, macromolecular synthesis, and redox homeostasis. In recent years, alterations in glucose metabolism have been implicated in melanoma development, metastatic efficiency, and BRAF-inhibitor treatment resistance. Due to the challenges of performing in vivo studies in humans, the majority of this knowledge is derived from in vitro data and mouse model systems. To characterise melanoma metabolism in a clinically relevant setting, we developed a clinical trial at UTSW to perform perioperative isotope tracing of [U-13C]glucose in patients undergoing standard-of-care surgical resection of melanoma and have now established a similar clinical trial at PMCC. In this protocol, patients receive a bolus of 8 grams of [U-13C]glucose followed by a continuous infusion of 4 grams/hour for an average of 3 hours prior to tumor acquisition. Peripheral blood and tumour samples are analysed through GC-MS to study glucose tracing and 13C-incorporation in downstream metabolites such as lactate, lipids, and TCA cycle intermediates. Thus far, we have obtained 16 melanoma samples from 10 patients who received perioperative infusions. All patients achieved a steady-state of glucose labelling in the peripheral circulation after 30 minutes. Importantly, we have observed that glucose oxidation occurs, to a variable degree, in all melanomas sampled. The extent of melanoma glucose utilisation and oxidation differs between patients and even within the same patient when examining melanoma samples from different metastatic sites. From 4 patients, we have generated patient-derived xenografts of their melanoma tumours and performed similar infusions to identify aspects of glucose metabolism that are and are not recapitulated in mouse model systems. To our knowledge, this is the first study to use stable isotope tracing to examine metabolic pathways in human melanoma. Future work will determine metabolic features of melanoma that are associated with prognosis and treatment response.