DNA damage induced by gamma-radiation in combination with ethylene oxide or propylene oxide in human fibroblasts.
To estimate the effects of interaction of gamma-rays and an epoxide, cell survival and induction of DNA double-strand breaks (DSBs) following combined exposure to ionizing radiation and ethylene oxide (EtO) or propylene oxide (PO) were studied in human fibroblasts. Two treatment protocols were applied: (a) the cells were pre-exposed to different doses of gamma-rays and then treated with epoxide, and (b) the cells were pretreated with epoxide and then exposed to different doses of gamma-rays. Here we show that order of the treatment did not play a role in cell survival and that the effect of combined exposure on cell killing was additive for both epoxides. As to DNA DSBs induction, however, a difference dependent upon the order of the treatment was observed. While EtO or PO treatment followed by gamma-rays exposure led to an increased number of DSBs at higher gamma-ray doses (2-3 Gy), no significant increase of DSBs was detected after the opposite order of the treatment (gamma-ray exposure followed by EtO or PO treatment).
Chovanec
M
M
Department of Molecular Genetics, Cancer Research Institute, Vlárska 7, 833 91 37, Bratislava, Slovakia.
Cedervall
B
B
Kolman
A
A
D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D002478:Cells, Cultured; D004247:DNA / Q000187:drug effects / Q000528:radiation effects; D004249:DNA Damage / Q000187:drug effects* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D016521:Electrophoresis, Gel, Pulsed-Field; D004852:Epoxy Compounds / Q000494:pharmacology*; D005027:Ethylene Oxide / Q000494:pharmacology*; D005347:Fibroblasts / Q000187:drug effects* / Q000528:radiation effects*; D005720:Gamma Rays; D006801:Humans
D004852:Epoxy Compounds; D004247:DNA; D005027:Ethylene Oxide; C009068:propylene oxide