Low‐power millimeter wave radiations do not alter stress‐sensitive gene expression of chaperone proteins

Abstract

This article reports experimental results on the influence of low-power millimeter wave (MMW) radiation at 60 GHz on a set of stress-sensitive gene expression of molecular chaperones, namely clusterin (CLU) and HSP70, in a human brain cell line. Selection of the exposure frequency is determined by its near-future applications for the new broadband civil wireless communication systems including wireless local area networks (WLAN) for domestic and professional uses. Frequencies around 60 GHz are strongly attenuated in the earth's atmosphere and such radiations represent a new environmental factor. An exposure system operating in V-band (50-75 GHz) was developed for cell exposure. U-251 MG glial cell line was sham-exposed or exposed to MMW radiation for different durations (1-33 h) and two different power densities (5.4 microW/cm(2) or 0.54 mW/cm(2)). As gene expression is a multiple-step process, we analyzed chaperone proteins induction at different levels. First, using luciferase reporter gene, we investigated potential effect of MMWs on the activation of transcription factors (TFs) and gene promoter activity. Next, using RT-PCR and Western blot assays, we verified whether MMW exposure could alter RNA accumulation, translation, or protein stability. Experimental data demonstrated the absence of significant modifications in gene transcription, mRNA, and protein amount for the considered stress-sensitive genes for the exposure durations and power densities investigated. The main results of this study suggest that low-power 60 GHz radiation does not modify stress-sensitive gene expression of chaperone proteins.

Millimeter wave treatment induces apoptosis via activation of the mitochondrial-dependent pathway in human osteosarcoma cells

“…Therefore, the energy of a millimeter wave can be absorbed by the organism through resonance. In turn, the energy can interfere with signal transduction and affect metabolism (8)(9)(10). It has been shown that a millimeter wave can evoke multiple biological effects (11,12) and is useful in the treatment of various types of diseases including cancers, such as hepatic cellular cancer patient (13,14).…”

Millimeter wave treatment promotes chondrocyte proliferation by upregulating the expression of cyclin-dependent kinase 2 and cyclin A

“…The frequency of the millimeter wave is in the same range of the frequency (0.5x10 10 -3x10 12 ) of coherent oscillation produced by biological organisms during metabolism. …”

“…Therefore, the energy of a millimeter wave can be absorbed by the organism through resonance. In turn, the (11)(12)(13). Our previous study showed that millimeter wave treatment induced the direct differentiation of mesenchymal stem cells (MSCs) to chondrocytes by upregulating the mRNAs of Cbfa1 and Sox9 and ultimately the levels of glycosaminoglycan and type II collagen.…”

Millimeter wave treatment inhibits the mitochondrion-dependent apoptosis pathway in chondrocytes

“…Therefore, the energy of MW can be absorbed by the organism through resonance. In turn, the energy may interfere with signal transduction and affect metabolism (10)(11)(12)(13). MW has been shown to evoke multiple biological effects and is beneficial in the treatment of OA.…”