Exposure to 900 MHz electromagnetic field induces an unbalance between pro-apoptotic and pro-survival signals in T-lymphoblastoid leukemia CCRF-CEM cells

• Published in: Journal of cellular physiology 2004-02, Vol.198 (2), p.324-332
• Main Authors: Marinelli, F., La Sala, D., Cicciotti, G., Cattini, L., Trimarchi, C., Putti, S., Zamparelli, A., Giuliani, L., Tomassetti, G., Cinti, Caterina
• Format: Article
• Language: English
• Subjects: Apoptosis - radiation effects; Blotting, Western; Cell Cycle - genetics; Cell Cycle - radiation effects; Cell Division - radiation effects; Electromagnetic Fields - adverse effects; Gene Expression - radiation effects; Humans; Leukocytes - radiation effects; Time Factors; Tumor Cells, Cultured; Tumor Suppressor Protein p53 - radiation effects
• ISSN: 0021-9541; 1097-4652
• DOI: 10.1002/jcp.10425

An Erratum has been published for this article in Journal of Cellular Physiology 198: 479–480, 2004. It has been recently established that low‐frequency electromagnetic field (EMFs) exposure induces biological changes and could be associated with increased incidence of cancer, while the issue remains unresolved as to whether high‐frequency EMFs can have hazardous effect on health. Epidemiological studies on association between childhood cancers, particularly leukemia and brain cancer, and exposure to low‐ and high‐frequency EMF suggested an etiological role of EMFs in inducing adverse health effects. To investigate whether exposure to high‐frequency EMFs could affect in vitro cell survival, we cultured acute T‐lymphoblastoid leukemia cells (CCRF‐CEM) in the presence of unmodulated 900 MHz EMF, generated by a transverse electromagnetic (TEM) cell, at various exposure times. We evaluated the effects of high‐frequency EMF on cell growth rate and apoptosis induction, by cell viability (MTT) test, FACS analysis and DNA ladder, and we investigated pro‐apoptotic and pro‐survival signaling pathways possibly involved as a function of exposure time by Western blot analysis. At short exposure times (2–12 h), unmodulated 900 MHz EMF induced DNA breaks and early activation of both p53‐dependent and ‐independent apoptotic pathways while longer continuous exposure (24–48 h) determined silencing of pro‐apoptotic signals and activation of genes involved in both intracellular (Bcl‐2) and extracellular (Ras and Akt1) pro‐survival signaling. Overall our results indicate that exposure to 900 MHz continuous wave, after inducing an early self‐defense response triggered by DNA damage, could confer to the survivor CCRF‐CEM cells a further advantage to survive and proliferate. J. Cell. Physiol. 198: 324–332, 2004© 2003 Wiley‐Liss, Inc.