Simultaneous hyperthermia at 43°c reduces radiation‐induced malignant transformation frequencies in golden hamster embryo cells

Studies were done to determine whether hyperthermia alone, or in simultaneous combination with X-rays, can induce malignant transformation in golden hamster embryo cells. Hyperthermia alone did not induce transformation. In fact, it reduced the frequency of the malignant transformation induced by X-rays. DNA damage as measured by alkaline elution and protein degradation were both induced by hyperthermia. However, the relationship of such damage to cell death is not yet clear. Our data indicate that hyperthermia either alone or in combination with X-ray treatment should be a safe method of cancer therapy.