The general public receives approximately half of its exposure to natural radiation through alpha (α)-particles from radon ( 222Rn) gas and its decay progeny. Epidemiological studies have found a positive correlation between exposure to 222Rn and lung carcinogenesis. An understanding of the transcriptional responses involved in these effects remains limited. In this study, genomic technology was employed to mine for subtle changes in gene expression that may be representative of an altered physiological state. Human lung epithelial cells were exposed to 0, 0.03, 0.3 and 0.9Gy of α-particle radiation. Microarray analysis was employed to determine transcript expression levels 4h and 24h after exposure. A total of 590 genes were shown to be differentially expressed in the α-particle radiated samples (false discovery rate (FDR)≤0.05). Sub-set of these transcripts were time-responsive, dose-responsive and both time- and dose-responsive. Pathway analysis showed functions related to cell cycle arrest, and DNA replication, recombination and repair (FDR≤0.05). The canonical pathways associated with these genes were in relation to pyrimidine metabolism, G2/M damage checkpoint regulation and p53 signaling (FDR≤0.05). Overall, this gene expression profile suggests that α-particle radiation inhibits DNA synthesis and subsequent mitosis, and causes cell cycle arrest.

Additional Metadata
Keywords 137Cs, 214Po, 222Rn, 238Pu, 241Am, Alpha particles, AROS, CT, Cy, DCT, EDTA, Epithelial cells, FBS, FC, FDR, Gene expression, IPA, MD, Microarray, NTP, OD, PA, PBS, QPCR, Radon, TBS, TST
Persistent URL dx.doi.org/10.1016/j.ijheh.2012.04.004
Journal International Journal of Hygiene and Environmental Health
Citation
Chauhan, V. (Vinita), Howland, M. (Matthew), Mendenhall, A. (Amy), O'Hara, S. (Shifawn), Stocki, T.J. (Trevor J.), McNamee, J.P. (James P.), & Wilkins, R.C. (2012). Effects of alpha particle radiation on gene expression in human pulmonary epithelial cells. International Journal of Hygiene and Environmental Health, 215(5), 522–535. doi:10.1016/j.ijheh.2012.04.004