Abstract P129: Ketogenic diet (KD) and targeting Warburg effect: Apparent toxicity of KD combination with 2-deoxy-D-glucose
Authors: Zielinski Rafal , Poimenidou Maria , Khuong Matthew , Grela Krzysztof , Cardenas-Zuniga Roberto , Skora Stanislaw , Fokt Izabela , Gagea Michael , Swain Jody , Zhou Sigmund , Priebe Waldemar 
Published: December 2021

Abstract
Introduction: Cancer dependence on glucose metabolism has been recognized as a potential target for the development of new anticancer therapies. Ketogenic low-carbohydrate diet (KD) and aerobic glycolysis is known as a Wartburg effect are two approaches linked by a common aim to reduce cancer glucose metabolism. 2-Deoxy-D-glucose (2-DG) has been shown to inhibit glycolysis and in effect to inhibit glucose metabolism and tumor growth in vitro and in vivo in a wide range of cancer models. Anticancer effects of 2-DG can be impacted by several factors including competition of glucose from the food intake. Ketogenic diet has been proposed as a strategy to inhibit proliferation of cancer cells that are highly dependent on glucose for growth and survival by reducing glucose access from food intake and switch to lipid metabolism. Combination of both approaches seemed to be a logical step to increase overall antitumor effects. Objective: The objective of the study was to determine safe doses of 2-DG in mice fed with KD and determine potential toxic side effects of 2-DG in mice maintained on carbohydrate-reduced vs. regular diet. Methods: Female CD-1 mice were maintained on a regular grain-based or carbohydrates-reduced diet (Research Diets (20 % Kcal Protein, 60 % Kcal Fat, 20 % Kcal carbohydrate). Animals were dosed with 2-DG once a day five times a week by oral gavage (PO) or intraperitoneal (IP) injections. Animals were watched daily for the development of toxicity symptoms. Results: No toxic side effects in mice fed with a regular, chow-base diet and treated orally with 2-DG were noted during the six-week treatment (doses ranged from 0.25 to 2.0 g/kg, five times/week). In the contrary, 2-DG-treaded animals maintained on KD showed dose-dependent toxicity with median survival (MS) 10 and 11 days for 1.0 and 2.0 g/kg respectively. For mice receiving 2-DG at 0.5 g/kg MS was 28 days and only 20% mice died in the group receiving 0.25 g/kg. In separate experiments mice treated with 2-DG orally or by intraperitoneal injections IP (1.5 g/kg) showed similar MS of 11 days. Complete blood count analysis of 2-DG treated animals fed with KD revealed acute thrombocytopenia. Post-mortem analysis of dissected organs indicated the development of acute interstitial pneumonia in treated mice. Conclusion: A highly reproducible toxicity leading to a rapid death of all treated animals maintained on a ketogenic diet was observed for 2-DG at doses 1.0 and 2.0 g/kg administered PO or IP. The same doses appeared to be safe in mice fed with a regular diet. The combination treatment toxic effects include acute thrombocytopenia and acute interstitial pneumonia. Delineation of the exact mechanism of toxicity requires additional studies. This study provides an important insight on the apparent toxicity of 2-DG when combined with the ketogenic diet and should serve as a reference for any future studies aimed to combine the ketogenic diet with inhibitors of glycolysis or other metabolic inhibitors.
Citation Format: Rafal Zielinski, Maria Poimenidou, Matthew Khuong, Krzysztof Grela, Roberto Cardenas-Zuniga, Stanislaw Skora, Izabela Fokt, Michael Gagea, Jody Swain, Sigmund Zhou, Waldemar Priebe. Ketogenic diet (KD) and targeting Warburg effect: Apparent toxicity of KD combination with 2-deoxy-D-glucose [abstract]. In: Proceedings of the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics; 2021 Oct 7-10. Philadelphia (PA): AACR; Mol Cancer Ther 2021;20(12 Suppl):Abstract nr P129.