ID Number		1956
Study Type		In Vitro
Model		50 Hz (ELF) exposure to breast tumor cells and analysis of their response to tamoxifen
Details		MCF-7 breast cancer cells were exposed to 50 Hz (ELF) for either 48 or 96 hours at multiple measured flux densities during tamoxifen treatment. The authors report cells became more resistent to tamoxifen with a maximal response at 1.2 microT. A subsequent study reported exposure at 1.2 microT for 48 or 96 hours increased the level of urokinase plasminogen activator and plasminogen activator inhibitor-1 (by 3.6 fold) and decreased the level of tissue plasminogen activagor (by 30%). The plasminogen activator system is involved in degrading the extracellular matrix during the metastatic process. The authors suggest ELF exposure may contribute to the tamoxifen resistance observed in many breast cancers after long-term treatment. In follow-up studies, the authors report that artificial stimulation of cells to increase adenylyl cyclase and decrease PKA activation (i.e., decreased phosphorylation of cAMP responsive element / CREB binding to CREs) inhibited estrogen-dependent proliferation. Exposure to ELF blocked the effect of the artificial adenylyl cyclase activation and the cells once again responded to estradiol for enhanced growth and increased expression of BRCA-1, p53, p21, and c-myc.
Findings		Effects
Status		Completed With Publication
Principal Investigator		University of Gottingen, Germany - rainer.girgert@med.uni-goettingen.de
Funding Agency		Nat'l Res Prog, Germany
Country		GERMANY
References		Girgert, R et al. Bioelectromagnetics., (2010) 31:237-245 Girgert, R et al. Biochem Biophys Res Commun., (2005) 336:1144-1149 Girgert, R et al. Int J Gynecol Cancer, (2009) 19:334-338
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