A) CoCl2 exposure mimics hypoxia chamber exposure as demonstrated by HIF-1α induction. B) Hypoxia (chamber, 1% O2) and CoCl2 exposure increase sensitivity to 2-DG in a clonogenic survival assay. C) IR exposure triggers a transient, reversible drop in cellular lactate levels. This effect is diminished by approximately 50% following exposure to CoCl2 for 24hr post-irradiation. All values normalized to corresponding control condition (1.0). D) Cells were exposed to increasing IR doses and effects of cell death ascertained using a clonogenic survival assay. 2-DG exposure radiosensitized tumors, while hypoxia (chamber, 1% O2) resulted in increased relative radioresistance. * indicates p-value < 0.05 compared to corresponding control condition. Each experiment was carried out at least in triplicate, with values indicating means and error bars representing standard deviation.