title: Enhancement of induced sister chromatid exchange and chromosomal aberrations by inhibitors of DNA repair processes.
abstract: The effect of post-treatment with inhibitors of DNA synthesis (hydroxyurea, aphidicolin) and repair (caffeine, 3-aminobenzamide) on the frequencies of chromosomal aberrations and sister chromatid exchange (SCE) induced by mitomycin C and decarbamoyl mitomycin C both in Chinese hamster cells and in human lymphocytes in vitro has been studied. The data show that in the case of Chinese hamster and human lymphocytes mitomycin C-treated cells there is an increased frequency of both chromosomal aberrations and SCE after a G2 post-treatment with the inhibitors, while no increase is observed for decarbamoyl mitomycin C-treated cells. Since SCE are DNA synthesis-dependent phenomenon, an increase in the frequency of SCE also in the G2 phase might suggest that after mitomycin C treatment there is a residual DNA synthesis still going on very late in the cell cycle.
mesh_terms: D000818:Animals; D016590:Aphidicolin; D002110:Caffeine / Q000633:toxicity; D002869:Chromosome Aberrations; D006224:Cricetinae; D003412:Cricetulus; D004247:DNA / Q000096:biosynthesis; D004260:DNA Repair / Q000187:drug effects*; D004224:Diterpenes / Q000633:toxicity; D005260:Female; D006801:Humans; D006918:Hydroxyurea / Q000633:toxicity; D016685:Mitomycin; D008937:Mitomycins / Q000633:toxicity; D012854:Sister Chromatid Exchange / Q000187:drug effects*
chemical_list: D004224:Diterpenes; D008937:Mitomycins; D016590:Aphidicolin; D002110:Caffeine; D016685:Mitomycin; D004247:DNA; D006918:Hydroxyurea