Gene Expression Changes in Medical Workers Exposed to Radiation

Abstract

The use of nuclear resources for medical purposes causes considerable concern about occupational exposure. Nevertheless, little information is available regarding the effects of low-dose irradiations protracted over time. We used oligomicroarrays to identify the genes that are transcriptionally regulated by persistent exposure to extremely low doses of ionizing radiation in 28 exposed professionals (mean cumulative effective dose +/- SD, 19 +/- 38 mSv) compared with a matched sample of nonexposed subjects. We identified 256 modulated genes from peripheral blood mononuclear cells profiles, and the main biological processes we found were DNA packaging and mitochondrial electron transport NADH to ubiquinone. Next we investigated whether a different pattern existed when only 22 exposed subjects with accumulated doses >2.5 mSv, a threshold corresponding to the natural background radiation in Italy per year, and mean equal to 25 +/- 41 mSv were used. In addition to DNA packaging and NADH dehydrogenase function, the analysis of the higher-exposed subgroup revealed a significant modulation of ion homeostasis and programmed cell death as well. The changes in gene expression that we found suggest different mechanisms from those involved in high-dose studies that may help to define new biomarkers of radiation exposure for accumulated doses below 25 mSv.

MicroRNA Expression Profiles of Whole Blood in Lung Adenocarcinoma

“…Radiation exposure, even at low dosage, has been shown to significantly affect levels of microRNAs in blood [63], [64], [65]. It is therefore possible that some of the changes in microRNA expression noted here are actually consequent to radiation exposure.…”

Embryonic ionizing radiation exposure results in expression alterations of genes associated with cardiovascular and neurological development, function, and disease and modified cardiovascular function in zebrafish

“…These genetic changes can be detected using transcriptomic technologies that permit thousands of genes to be analyzed in a single step to portray a genome-wide view of gene expression alterations. Few studies to date have used these technologies to identify transcriptomic signatures and genetic biomarkers related to IR exposure (Yin et al, 2003; Amundson et al, 2004; Dressman et al, 2007; Meadows et al, 2008, 2010; Lowe et al, 2009; Morandi et al, 2009; Kabacik et al, 2011; Wyrobek et al, 2011; Jaafar et al, 2013). These studies are starting to elucidate genetic targets associated with IR induced alterations, but were conducted in either cell culture systems, mature models, or from adult human peripheral blood samples.…”

Deoxyribonucleic acid damage-associated biomarkers of ionising radiation: current status and future relevance for radiology and radiotherapy

“…A long-term study of lymphocytes at 2, 7 and 55 days showed up to only five genes in common from the acute-to late-stage responses [41]. Different genes have also been shown to be up-regulated at low doses in comparison with high doses [42]. At low doses, a gender effect is also seen to influence the gene expression [40].…”