[Additive effects of carboplatin (CBDCA) and Co-60 gamma rays in human tumor cells in vitro]

In vitro investigations on the combination effect of radiation and carboplatin (CBDCA) in three human cell lines (HeLa, MRI-186 Caski) show purely additive effects. Study of the molecular lesions gave considerable differences in the time course of repair of radiation induced DNA-double strand-breaks and of formation of DNA-crosslinks by carboplatin. However, sequential treatment with intervals of up to +/- 24 hours resulted also in an additive effect. In the experimental systems studied, a true radiosensitization was not demonstrated.