Whole-genome expression analysis in primary human keratinocyte cell cultures exposed to 60 GHz radiation.
ABSTRACT The main purpose of this study is to investigate potential responses of skin cells to millimeter wave (MMW) radiation increasingly used in the wireless technologies. Primary human skin cells were exposed for 1, 6, or 24 h to 60.4 GHz with an average incident power density of 1.8 mW/cm(2) and an average specific absorption rate of 42.4 W/kg. A large-scale analysis was performed to determine whether these exposures could affect the gene expression. Gene expression microarrays containing over 41,000 unique human transcript probe sets were used, and data obtained for sham and exposed cells were compared. No significant difference in gene expression was observed when gene expression values were subjected to a stringent statistical analysis such as the Benjamini-Hochberg procedure. However, when a t-test was employed to analyze microarray data, 130 transcripts were found to be potentially modulated after exposure. To further quantitatively analyze these preselected transcripts, real-time PCR was performed on 24 genes with the best combination of high fold change and low P-value. Five of them, namely CRIP2, PLXND1, PTX3, SERPINF1, and TRPV2, were confirmed as differentially expressed after 6 h of exposure. To the best of our knowledge, this is the first large-scale study reporting on potential gene expression modification associated with MMW radiation used in wireless communication applications. Bioelectromagnetics. © 2011 Wiley-Liss, Inc.
- SourceAvailable from: Denis Habauzit[Show abstract] [Hide abstract]
ABSTRACT: Radiofrequency radiations constitute a new form of environmental pollution. Among them, millimeter waves (MMW) will be widely used in the near future for high speed communication systems. This study aimed therefore to evaluate the biocompatibility of MMW at 60 GHz. For this purpose, we used a whole gene expression approach to assess the effect of acute 60 GHz exposure on primary cultures of human keratinocytes. Controls were performed to dissociate the electromagnetic from the thermal effect of MMW. Microarray data were validated by RT-PCR, in order to ensure the reproducibility of the results. MMW exposure at 20 mW/cm2, corresponding to the maximum incident power density authorized for public use (local exposure averaged over 1 cm2), led to an increase of temperature and to a strong modification of keratinocyte gene expression (665 genes differentially expressed). Nevertheless, when temperature is artificially maintained constant, no modification in gene expression was observed after MMW exposure. However, a heat shock control did not mimic exactly the MMW effect, suggesting a slight but specific electromagnetic effect under hyperthermia conditions (34 genes differentially expressed). By RT-PCR, we analyzed the time course of the transcriptomic response and 7 genes have been validated as differentially expressed: ADAMTS6, NOG, IL7R, FADD, JUNB, SNAI2 and HIST1H1A. Our data evidenced a specific electromagnetic effect of MMW, which is associated to the cellular response to hyperthermia. This study raises the question of co-exposures associating radiofrequencies and other environmental sources of cellular stress.PLoS ONE 01/2014; 9(10):e109435. · 3.53 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: Mots-clefs : ondes millimétriques, effets biologiques, études in vivo et in vitro. Key words: millimeter waves, biological effect, in vivo and in vitro studies. Résumé: Les ondes millimétriques correspondent à la gamme des fréquences comprises entre 30 GHz et 300 GHz. De nombreuses applications existent et émergent actuellement dans ce domaine, notamment en télécommunications, imagerie et surveillance. De plus, certaines de ces fréquences sont utilisées en thérapie en Europe de l'Est, ce qui suggère que des interférences avec l'organisme sont possibles. Cette revue vise à résumer l'état des connaissances actuelles sur les interactions ondes millimétriques / matière vivante. Quelques exemples représentatifs de la littérature scientifique seront exposés dans cette revue. Nous décrirons enfin plus en détail des résultats obtenus par notre laboratoire, portant sur l'impact des paramètres d'exposition sur le déclenchement du stress cellulaire et sur la modification de l'expression génique.
- [Show abstract] [Hide abstract]
ABSTRACT: Aperture-field exposure setups are applied in experiments detecting the effects of millimeter-wave (MMW) exposure on cells in vitro. In this paper, the studied exposure setup with standard components includes cells plated in a 35-mm Petri dish at the aperture of a horn irradiating 50.0-GHz MMW. Incorporating the subvoxel model and symmetry formulas, the finite-difference time-domain algorithm of the Maxwell equations and the finite-difference algorithm of the Pennes bioheat equation are used to calculate the specific absorption rate (SAR), absorption efficiency of the MMW power, and temperature rise in the cell culture. The numerical methods and models are supported by experimental measurement and theoretical analyses. The exposure of 31.2-mW MMW results in an averaged SAR of 44.9 W/kg in cells, quantitatively compatible with the International Commission on Non-Ionizing Radiation Protection limits to the incident power density. 46.9% of the MMW power is efficiently absorbed and accumulates a maximum temperature rise of 0.12°C in cells. The exposure intensity is selectable with acceptable homogeneity by proper cell sampling. The MMW multiple reflection of the aperture-field exposure is analyzed about its significant influences on the dosimetry and temperature results. Another comparison reveals the efficacious power matching of the Petri dish and its dosimetric contribution. The power threshold for time-unlimited exposures, time limits for high-power exposures, and adaptive air cooling are quantified to control the temperature variance within ±0.1°C. This paper presents the first detailed quantification and characterization of the dosimetry and temperature environments for the MMW aperture-field exposure setup in application to in vitro experiments for over 30 years.IEEE Transactions on Microwave Theory and Techniques 11/2012; 60(11):3608-3622. · 2.23 Impact Factor