At 16-20 hr postirradiation incubation with caffeine enhances X-ray killing of rodent and human cells. Cells tested were Chinese hamster ovary (CHO-K1), lung (CHL), V79, mouse L, HeLa S3, human fibroblasts (AF288, TC171, FS9, CRL1166), and a human-hamster hybrid. The effect of caffeine on the X-ray survival curve of these cells was to remove the initial shoulder without significantly altering the mean lethal dose (D0). This action can be achieved at caffeine concentrations which of themselves cause less than 15% killing. In randomly growing CHO-K1 cells the caffeine-sensitive process occurs with a half-time of 2-5 hr after irradiation. These experiments indicate the existence in human and rodent cells of caffeine-inhibited genome repair for X-ray damage.
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging