Selective killing of glucose and oxygen-deprived HeLa cells by hyperthermia.

We previously have reported that glucose deprivation specifically enhance cell killing by hyperthermia in the absence of oxygen. The present studies were carried out to evaluate the interplay of glucose and oxygen on cell killing by hyperthermia (37 to 42 degrees) for up to 4 hr under varying concentrations of glucose (0 to 1 mg/ml) and oxygen (0 to 21%). pH 7.4 was maintained in all trials. In the absence of oxygen, enhanced cell killing at 40 and 42 degrees was seen with glucose concentrations below 0.1 and 0.25 mg/ml of media, respectively. In the absence of glucose, enhanced killing was seen when oxygen concentrations were below 1 and 2% at 40 and 42 degrees, respectively. The radiosensitivity of the cells was influenced only by the oxygen concentration during irradiation and not by glucose. These results indicate that oxygen and glucose are important modifying factors of cell lethality by hyperthermia.