Excision repair differences in rat fibroblasts.

By using a cellular transformation system, which has been developed by Graffi et al., we analysed differences in the excision capacity of UV-induced dimers in normal cells, in vitro transformed cells and in malignant cells derived from a rat fibrosarcoma. The results suggest that both the transformed and the tumour-derived cells exhibit a kinetic pattern of excision repair different from that of the normal cells. Recognition of the dimers and the incision rate are more complete in the normal cell.