Abstract

Recovery from radiation- or cisplatin-induced lethal damage has been studied in euoxic normal human foetal lung fibroblasts (HFL cells) that remain viable for at least 20 days in plateau-phase culture. After a 1 hour treatment with cisplatin the half-time of recovery was about 2 days. By contrast recovery after radiation was more rapid with half-times of approximately 10 h. There was no further measurable recovery after 2 days. With either agent the recovery ratios (RR) were dose-dependent but recovery (following treatment with equitoxic doses of the two agents) was appreciably greater after cisplatin (RR approximately 123 after 40 microM for 1 h) than after radiation (RR approximately 15 after 900 cGy). When radiation (900 cGy) was combined with cisplatin (40 microM for 1 h) the cell survival, measured at 5 days or later times after the treatments, was not significantly less than that predicted by the additive, independent effects of both agents (calculated as the product of their respective effects on cell survival) irrespective of whether cisplatin was given 1 h before, during or for 1 h immediately after radiation. In euoxic, exponentially growing HFL or HeLa cells there was no evidence that combinations of cisplatin and radiation gave more than additive toxic effects in the protocols tested. The combined effects of cisplatin or carboplatin and whole-body irradiation given 45 min later, on human melanoma cells (assessed by their colony-forming abilities in vitro) growing in thymectomised mice, were essentially the same as that predicted by the additive, independent effects of the two agents.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.