INDUCTION OF DNA DOUBLE-STRAND BREAKS IN CHO-K1 CELLS BY CARBON-IONS

Citation
J. Heilmann et al., INDUCTION OF DNA DOUBLE-STRAND BREAKS IN CHO-K1 CELLS BY CARBON-IONS, International journal of radiation biology, 68(2), 1995, pp. 153-162
Citations number
51
Categorie Soggetti
Radiology,Nuclear Medicine & Medical Imaging","Nuclear Sciences & Tecnology
ISSN journal
09553002
Volume
68
Issue
2
Year of publication
1995
Pages
153 - 162
Database
ISI
SICI code
0955-3002(1995)68:2<153:IODDBI>2.0.ZU;2-Y
Abstract
Radiation-induced DNA double-strand breaks (dsbs) were measured in CHO -K1 cells by means of an experimental approach involving constant-fiel d gel electrophoresis and densitometric scanning of ethidium bromide s tained gels. For X-irradiation, an induction efficiency of 36 +/- 5 ds bs (Gy X cell)(-1) was determined. With this set-up, the induction of dsbs was investigated in CHO-K1 cells after irradiation with accelerat ed carbon ions with specific energies ranging from 2.7 to 261 MeV/u. T his set of particle beams covers the important linear energy transfer (LET) range between 17 and 400 keV/mu m, where maximum efficiencies ha ve been reported for other cellular endpoints like inactivation or mut ation induction. For LETs up to 100 keV/mu m, RBEs of similar to 1 hav e been determined, while efficiencies per unit dose decline for higher LETs. No RBE maximum > 1 was found. Data are compared with published results on dsb induction in mammalian cells by radiations of comparabl e LET.