Effect of cycloheximide on heat-induced cell killing, radiosensitization, and loss of cellular DNA polymerase activities in Chinese hamster ovary cells.

A whole-cell assay technique for DNA polymerase alpha and beta was used to measure the activities of both enzymes in Chinese hamster ovary cells after hyperthermic treatment at 43 degrees C in the presence or absence of 10 micrograms/ml cycloheximide (CHM). In the same experiments, the effect of CHM on heat killing and heat radiosensitization was also investigated. CHM treatment before and during heating protected the cells for all three end points, i.e., heat-induced cell killing, radiosensitization, and loss of cellular DNA polymerase activities.