EMF Health-effects Research
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Expression of proto-oncogene and activities of multiple transcription factors in RF exposed cells, using C3H10T1/2 mouse embryo fibroblast cells exposed to 835.62 and 847.74 MHz cellphone radiations. Goswami PC, Albee LD, Parsian AJ, Baty JD, Moros EG, Pickard WF, Roti-Roti JL, Hunt CR, Presented at the 1997 Muchaelson Conference. Radiat Res 151(3):300-309, 1999 Motorola-funded Contractors: Radiation Oncology Center, Washington University School of Medicine, St Louis, Missouri
This study explored possible effects of analog (835.62 MHz FMCW) or digital (847.74 MHz CDMA) signals on gene expression and other changes in mouse fibroblast cells. Exposure at 0.6 W/kg did not produce evidence of measurable changes in c-jun or c-myc expression or in DNA binding activity of AP-1, AP-2 or NFkB proteins in any phase of the cell cycle (quiescent, transit to proliferation, exponential growth). In exponential growth phase only, there was a slight (1.4 to two-fold) statistically significant increase in c-fos expression levels warranting further study to assess the reproducibility of the findings. THE ORIGINAL ABSTRACTRadiat Res 151(3):300-309, 1999 This study was designed to determine whether two differently modulated radiofrequencies of the type generally used in cellular phone communications could elicit a general stress response in a biological system. The two modulations and frequencies studied were a frequency-modulated continuous wave (FMCW) with a carrier frequency of 835.62 MHz and a code division multiple-access (CDMA) modulation centered on 847.74 MHz. Changes in proto-oncogene expression, determined by measuring Fos, Jun, and Myc mRNA levels as well as by the DNA-binding activity of the AP1, AP2 and NF-kappaB transcription factors, were used as indicators of a general stress response. The effect of radiofrequency exposure on proto-oncogene expression was assessed:
Exposure of serum-deprived cells to 835.62 MHz FMCW or 847.74 MHz CDMA microwaves (at an average specific absorption rate, SAR, of 0.6 W/kg) did not significantly change the kinetics of proto-oncogene expression after serum stimulation. Similarly, these exposures did not affect either the Jun and Myc mRNA levels or the DNA-binding activity of AP1, AP2 and NF-kappaB in exponential cells during transit to plateau-phase growth. Therefore, these results suggest that the radiofrequency exposure is unlikely to elicit a general stress response in cells of this cell line under these conditions. However, statistically significant increases (approximately 2-fold, P = 0.001) in Fos mRNA levels were detected in exponential cells in transit to the plateau phase and in plateau-phase cells exposed to 835.62 MHz FMCW microwaves. For 847.74 MHz CDMA exposure, the increase was 1.4-fold (P = 0.04). This increase in Fos expression suggests that expression of specific genes could be affected by radiofrequency exposure. |
Additional Web NotesSee comments. This is another case where Motorola's PR department (probably Mays Swicord) has written this abstract to down-play the fact that the discovered evidence of cancerous changes. This c-fos gene is a member of so called immediate-early response gene family (IERG). It regulates the expression of other target genes and is involved in cell proliferation and differentiation. In the brain, c-fos is a cause of neuronal activity and injury. The fact that this particular research group considers such finding as "statistically significant" means that it is not "slight". And such findings "warrant further study" to see what the hell is going on -- not just to "assess the reproducibility". They have chosen words which suggest that the technique might have been faulty, but these are weazle words. S.F. Comment No.1: In this study, the researchers found an increase in expression of the proto-oncogene c-fos in fibroblast cells exposed to cell phone radiations at an SAR of 0.6 W/kg. This occurs only at the exponential growth phase, when cells are undergoing rapid division. The increase was between 1.4- 2.0-times that of the control, and the authors concluded in the abstract that "this increase in Fos expression suggests that expression of specific genes could be affected by radiofrequency (radiation) exposure." In the publication 'Recent Motorola-supported research related to the safety of wireless telephones' distributed by Motorola in October 1999, the results of the Goswami study was described as
So, the question becomes: "Is a 1.4- to 2-fold increase in c-fos expression a small insignificant increase, or not?' In a paper published by Hong et al (Induction of c-fos and junB mRNA following in vivo brain irradiation, Molecular Brain Research 48:223-228, 1997), the authors reported 2.2- and 4-fold increases respectively in c-fos expression in brains of mice exposed to 2 Gy (200 rads) and 25 Gy (2500 rads) of ionizing radiation. There is another study, also funded by Motorola, in which c-fos expression was studied in the brain of mice exposed to Iridium phone radiation. (Morrissey et al., Iridium exposure increases c-fos expression in the mouse brain only at levels which likely result in tissue heating. Neuroscience 92:1539-1546, 1999). In that study, the 'positive controls' (i..e, animals which were deliberately given a treatment known to affect c-fos substantially) were treated with Lindane, a drug that induces seizure, and the authors reported an increase in c-fos of only 2.2-fold in the cortex of the brains of these 'positive controls'. So this gives us some measure of what the researchers really believe to be significant; obviously positive controls at 2.2-times normal are seen here as highly significant. |
