Mammography is used to screen a large fraction of the population for @entity0 , and mammography quality X rays are speculated to be more damaging than the higher energy X rays used for other diagnostic procedures. The radiation dose delivered to breast cells as a result of these screening exposures may be a concern. The purpose of this current study was to determine the relative biological effectiveness (RBE) of low-energy mammography X rays for radiation-induced DNA double-strand breaks evaluated using a highly sensitive automated @entity15664 assay. Automation of the @entity15664 assay enabled the quantification and analysis of meaningful image-based features, including foci counting, within the cell nuclei. Nontumorigenic, @entity1 breast epithelial MCF-10A cells were irradiated in the low-dose range with approximately 3-30 mGy of 29 kVp mammography X rays or (137)Cs (662 keV) gamma rays. The induction and resolution of the @entity15664 foci did not differ significantly between exposures to (137)Cs gamma rays and 29 kVp X rays. The RBE was calculated to be 1.1 with a standard deviation of 0.2 for the initial number of radiation-induced double-strand breaks. The radiation dose from a single mammogram did not yield a significant change in the number of detectable foci. However, analysis of additional features revealed subtle differences in the distribution of @entity15664 throughout the nuclei after exposure to the different radiation qualities. A single mammogram was sufficient to alter the distribution of @entity15664 within the nuclear area, but not into discrete foci, while a dose-matched gamma exposure was not sufficient to alter the distribution of @entity15664 . Our results indicate that exposure to clinically relevant doses of low-energy mammography quality X rays does not induce more DNA double-strand breaks than exposure to higher energy photons.

The Relative Biological Effectiveness of Low-Dose Mammography Quality X Rays in the XXXX Breast MCF-10A Cell Line.

@entity1 :: ('9606', 'Species') :: ['human'] @entity15664 :: ('7158', 'Gene') :: ['53BP1'] @entity0 :: ('MESH:D001943', 'Disease') :: ['breast cancer']
@entity1 :: (9606,Species) :: ['Human']
