2-Deoxy-D-Glucose inhibits aggressive triple-negative breast cancer cells by targeting glycolysis and the cancer stem cell phenotype

Due to limited availability of pharmacological therapies, triple-negative breast cancer (TNBC) is the subtype with worst outcome. We hypothesised that 2-Deoxy-D-Glucose (2-DG), a glucose analogue, may hold potential as a therapy for particularly aggressive TNBC. We investigated 2-DG's effects on TNBC cell line variants, Hs578T parental cells and their isogenic more aggressive Hs578Ts(i)₈ variant, using migration, invasion and anoikis assays. We assessed their bioenergetics by Seahorse. We evaluated metabolic alterations using a Seahorse XF Analyzer, citrate synthase assay, immunoblotting and flow cytometry. We assessed the cancer stem cell (CSC) phenotype of the variants and 2-DG's effects on CSCs. 2-DG significantly inhibited migration and invasion of Hs578Ts(i)₈ versus Hs578T and significantly decreased their ability to resist anoikis. Investigating 2-DG's preferential inhibitory effect on the more aggressive cells, we found Hs578Ts(i)₈ also had significantly decreased oxidative phosphorylation and increased glycolysis compared to Hs578T. This is likely due to mitochondrial dysfunction in Hs578Ts(i)₈, shown by their significantly decreased mitochondrial membrane potential. Furthermore, Hs578Ts(i)₈ had a significantly increased proportion of cells with CSC phenotype, which was significantly decreased by 2-DG. 2-DG may have benefit as a therapy for TNBC with a particularly aggressive phenotype, by targeting increased glycolysis. Studies of more cell lines and patients' specimens are warranted.