Selective potentiation of hyperthermic killing of hypoxic cells by 5-thio-D-glucose

The modification of cell lethality at elevated temperatures by 5-thio-D-glucose, the nearest analog of D-glucose was studied with the use of HeLa cells in the presence or absence of oxygen. When the cells were exposed to temperatures ranging from 40.5-42 degrees for 0.5 to 4 hr in the presence of 5-thio-D-glucose (5 mM), there was a selective potentiation of hyperthermic killing of hypoxic cells. No enhanced killing of oxic cells by 5-thio-D-glucose was seen at these temperatures. These results indicate that glucose metabolism may be involved in influencing the heat sensitivity of hypoxic cells. The low toxicity of 5-thio-D-glucose and its specificity to hypoxic cells suggest that it may be a useful adjuvant to hyperthermic therapy.