BIOCHEMICAL MECHANISM OF SELECTIVE HEAT SENSITIVITY OF CANCER CELLS .2. STUDIES ON NUCLEIC ACIDS AND PROTEIN SYNTHESIS

The effect of temperature in the range from 38° to 43°C upon incorporation of labeled precursors into DNA, RNA and protein of Novikoff and Morris 5123 hepatoma cells was investigated. A striking inhibition by temperature was found in both kind of tumor cells whereas regenerating liver cells were not affected. The temperature effect was observed also in cells from a human osteosarcoma. Cell free preparations were temperature insensitive. d-glucose added to the incubation mixture caused a marked inhibition. Filipin and ethanol were found to inhibit the incorporation into tumor cells at concentrations which did not significantly affect regenerating liver cells. A possible involvement of membranes in the mechanism of heat sensitivity of tumor cells is suggested. © 1969.