Genetic Variation and Radiation Quality Impact Cancer Promoting Cellular Phenotypes in Response to HZE exposure

Publication date: Available online 21 October 2018Source: Life Sciences in Space ResearchAuthor(s): Deepa M. Sridharan, Shiena Enerio, Chris Wang, Mark A. LaBarge, Martha R. Stampfer, Janice M. PluthAbstractThere exists a wide degree of genetic variation within the normal human population which includes disease free individuals with heterozygote defects in major DNA repair genes. A lack of understanding of how this genetic variation impacts cellular phenotypes that inform cancer risk post heavy ion exposure poses a major limitation in developing personalized cancer risk assessment astronauts. We initiated a pilot study with Human Mammary Epithelial Cell strains (HMEC) derived from wild type, a p16 silenced derivative of wild type, and various genetic variants that were heterozygote for DNA repair genes; BRCA1, BRCA2 and ATM. Cells strains were exposed to different high and low LET radiation qualities to generate both simple and complex lesions and centrosome aberrations were examined as a surrogate marker of genomic instability and cancer susceptibility post different exposures. Our results indicate that centrosome aberration frequency is higher in the genetic variants under study. The aberration frequency increases with dose, complexity of the lesion generated by different radiation qualities and age of the individual. This increase in genomic instability correlates with elevated check-point activation post radiation exposure. These studies suggest that the influence of indi...
Source: Life Sciences in Space Research - Category: Biology Source Type: research