title: Correlation between cell death and induction of non-rejoining PCC breaks by carbon-ion beams.
abstract: We have shown a correlation between cell death and induction of non-rejoining chromatin breaks in two normal human cells and three human tumor cell lines irradiated by carbon-ion beams and X rays. Non-rejoining chromatin breaks were measured by counting the number of remaining chromatin fragments detected by the premature chromosome condensation (PCC) technique. Carbon-ion beams were accelerated by the Heavy Ion Medical Accelerator in Chiba (HIMAC). The cells were irradiated by two different mono-LET beams (LET = 13 keV/micrometer and 77 keV/micrometer ) and 200 kV X rays. The RBE values of cell death for carbon-ion beams relative to X rays were 1.1 to 1.4 for 13 keV/micrometer beams and 2.5 to 2.9 for 77 keV/micrometer beams. The induction rate of non-rejoining PCC breaks per cell per Gy was found to be highest for the 77 keV/micrometer beams for all of the cell lines. The results found in this study show that there is a good correlation between cell death and induction of non-rejoining PCC breaks for these human cell lines.
authors.affiliation: National Institute of Radiological Sciences, Chiba-shi, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Suzuki
authors.forename: Y
authors.initials: Y
authors.lastname: Kase
authors.forename: T
authors.initials: T
authors.lastname: Kanai
authors.forename: K
authors.initials: K
authors.lastname: Ando
mesh_terms: D001254:Astrocytoma / Q000473:pathology; D001932:Brain Neoplasms / Q000473:pathology; D002244:Carbon; D016923:Cell Death; D002470:Cell Survival / Q000528:radiation effects; D002843:Chromatin / Q000528:radiation effects*; D019457:Chromosome Breakage; D005347:Fibroblasts / Q000528:radiation effects; D005909:Glioblastoma / Q000473:pathology; D020450:Heavy Ions; D006801:Humans; D018499:Linear Energy Transfer; D008168:Lung / Q000166:cytology / Q000196:embryology; D018328:Melanoma, Amelanotic / Q000473:pathology; D010315:Particle Accelerators; D012062:Relative Biological Effectiveness; D012878:Skin Neoplasms / Q000473:pathology; D014407:Tumor Cells, Cultured / Q000528:radiation effects; D014965:X-Rays
chemical_list: D002843:Chromatin; D002244:Carbon