Induction and rejoining of DNA double-strand breaks and interphase chromosome breaks after exposure to x-rays in one normal and two hypersensitive human fibroblast cell lines

Journal Article · Sun Oct 01 04:00:00 EDT 1995 · Radiation Research

DOI:https://doi.org/10.2307/3579232· OSTI ID:160181

Badie, C; Alsbeih, G; Malaise, E P ^[1]

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1. Institute Gustave-Roussy, Villejuif (France); and others

The aim of this work was to measure simultaneously and in a quantitative manner double-strand breaks (DSBs), interphase chromosome breaks and cell lethality either immediately after irradiation, or at various times thereafter (up to 24 h), in cells of three nontransformed human fibroblast cell lines of widely different intrinsic radiosensitivity. We wished to assess initial damage, repair kinetics and residual damage at the DNA and the chromosome level, and to correlate these parameters with cell killings. We employed HF19 cells, a normal fibroblast cell line, AT2 cells, a radiosensitive cell line from a patient suffering from ataxia telangiectasia (AT), and 180BR cells, a radiosensitive cell line from a patient with no clinical symptoms of AT. AT2 and 180BR cells, in addition to being radiosensitive, also display a reduced ability to repair potentially lethal damage compared to HF19 cells. The yield of DSBs, as measured by pulsed-field gel electrophoresis, is similar in all three cell lines (slopes correspond to 1.6-1.7% Gy{sup -1} of DNA-associated radioactivity released from the gel well into the lane). In contrast, residual DSBs measured 24 h after irradiation are almost zero for HF19 cells (0.1% confidence interval=0-1.4%), but are 12.5% ({plus_minus}2.3%) and 43.8% ({plus_minus}1.2%) of those measured immediately after irradiation in HF19, AT2 and 180BR cells, respectively. Neither the initial yield of DSBs nor that of excess interphase chromosomes breaks can explain the differences in radiosensitivity between the three cell lines; however, there is a correlation between residual DSBs, rate of DSB rejoining at 24 h, residual interphase chromosome breaks on the one hand and cell survival on the other hand. 74 refs., 6 figs., 4 tabs.

• Sponsoring Organization: USDOE
• OSTI ID: 160181
• Journal Information: Radiation Research, Journal Name: Radiation Research Journal Issue: 1 Vol. 144; ISSN 0033-7587; ISSN RAREAE
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
56 BIOLOGY AND MEDICINE
APPLIED STUDIES
BIOLOGICAL PATHWAYS
BIOLOGICAL RADIATION EFFECTS
CHROMOSOME BREAKAGE
COMPARATIVE EVALUATIONS
DNA REPAIR
ELECTROPHORESIS
FIBROBLASTS
IRRADIATION
RADIOSENSITIVITY
STRAND BREAKS