BIOCHEMICAL MECHANISM OF SELECTIVE HEAT SENSITIVITY OF CANCER CELLS .I. STUDIES ON CELLULAR RESPIRATION

The effect of temperature on respiration and anaerobic glycolysis of Novikoff and minimal deviation 5123 hepatoma was investigated. Exposure of tumor cells at 43°C in aerobic conditions caused an inhibition of oxygen uptake and also, to a minor extent, of anaerobic glycolysis. Regenerating liver cells were not inhibited. Disrupted tumor cells were temperature insensitive. Ethanol caused a severe inhibition of respiration in Novikoff hepatoma cells. The effect of ethanol is increased by the higher temperature. Filipin inhibited oxygen uptake by Novikoff hepatoma. The effect was not enhanced by temperature. Regenerating liver was inhibited only by much higher concentrations of ethanol and filipin. The inhibition by ethanol was also in this case enhanced by a higher temperature. The lability of some organized system (i.e. surface or lysosomal membranes) is suggested to explain the observed behaviour of tumor cells. © 1969.