Medical/biological study (experimental study)

Microwave electromagnetic field regulates gene expression in T-lymphoblastoid leukemia CCRF-CEM cell line exposed to 900 MHz med./bio.

By: Trivino Pardo JC, Grimaldi S, Taranta M, Naldi I, Cinti C

Published in: Electromagn Biol Med 2012; 31 (1): 1-18

Aim of study (acc. to author)

To study whether exposure to microwaves alters gene expression and cell viability in T-lymphoblastoid leukemia cells.

Background/further details

Four groups were examined: 1.) 2 hours sham exposure, 2.) 48 hours sham exposure, 3.) 2 hours exposure and 4.) 48 hours exposure.

Endpoint

molecular biosynthesis: gene expression

Exposure

- 900 MHz
- microwaves

Exposure	Parameters
Exposure 1: 900 MHz Modulation type: CW Exposure duration: continuous for 2 or 48 hours	SAR: 3.5 mW/kg power density: 23.68 mW/m² electric field strength: 3 V/m maximum magnetic field strength: 8 mA/m

General information

literature reference: Stuchly, M. A., Stuchly, S. S. (1986). Experimental radio and microwave dosimetry. In: Polk, C., Postow, E. Handbook of Biological Effects of Electromagnetic Fields (pp. 229-272). Boca Raton, FL: CRC Press.

Exposure 1

Main characteristics

Frequency	900 MHz
Type	electromagnetic field
Exposure duration	continuous for 2 or 48 hours

Modulation

Modulation type	CW

Exposure setup

Exposure source	TEM cell
Chamber	aluminium box with 3 mm thickness in order to obtain 75 Ohm impedance; box contains a small aluminium septum, which divides the inner part into two equal parts; field was perpendicular to the septum plane; to allow gaseous exchange between incubator and petri dishes, one side of the TEM cell was made of a removable 2.5 mm mesh; five petri dishes of 10 cm diameter were placed in TEM cell at 1 cm distance above and below the septum
Setup	transverse electromagnetic cell was placed in incubator
Sham exposure	A sham exposure was conducted.
Additional info	50 Hz-electric and magnetic field was generated by incubator, but did not exceed 0.8 V/m and 0.16 µT

Parameters

Measurand	Value	Type	Method	Mass	Remarks
SAR	3.5 mW/kg	-	-	-	-
power density	23.68 mW/m²	-	-	-	-
electric field strength	3 V/m	maximum	measured	-	-
magnetic field strength	8 mA/m	-	measured	-	-

Reference articles

Marinelli F et al. (2004): Exposure to 900 MHz electromagnetic field induces an unbalance between pro-apoptotic and pro-survival signals in T-lymphoblastoid leukemia CCRF-CEM cells

Exposed system:

intact cell/cell culture
CCRF-CCM cells (human acute T-lymphoblastoid leukemia)

Methods Endpoint/measurement parameters/methodology

molecular biosynthesis: gene expression (DNA microarray, Western blot)
cell viability/cell division/proliferation: cell viability (MTT assay), cell cycle state (flow cytometry)

Investigated system:

DNA/RNA
intact cell/cell culture

Time of investigation:

after exposure

Main outcome of study (acc. to author)

After 48 hours, a significantly decreased number of viable cells was found in the exposed cell cultures when compared to the 48 hours-control group. After 2 hours of exposure, the number of cells undergoing apoptosis was significantly increased in comparison to the 2 hours control group. This effect decreased after 48 hours, but remained statistically significant.
Analysis via microarray revealed that the gene expression of numerous genes involved in DNA repair, apoptosis, cell cycle regulation, angiogenesis and chromosomal organization was significantly down-regulated, respectively up-regulated in the exposed groups compared to the control groups. Most of the results were verified via Western blot.
The results indicate that microwave-exposure could induce changes in gene expression and influence the cell growth.

Study character:

medical/biological study
experimental study
full/main study

Study funded by

National Research Council (CNR; Consiglio Nazionale delle Ricerche); Italy

Palumbo R et al. (2008): Exposure to 900 MHz radiofrequency radiation induces caspase 3 activation in proliferating human lymphocytes
Remondini D et al. (2006): Gene expression changes in human cells after exposure to mobile phone microwaves
Lantow M et al. (2006): Comparative study of cell cycle kinetics and induction of apoptosis or necrosis after exposure of human mono mac 6 cells to radiofrequency radiation
Lee S et al. (2005): 2.45 GHz radiofrequency fields alter gene expression in cultured human cells
Marinelli F et al. (2004): Exposure to 900 MHz electromagnetic field induces an unbalance between pro-apoptotic and pro-survival signals in T-lymphoblastoid leukemia CCRF-CEM cells
Port M et al. (2003): Influence of high-frequency electromagnetic fields on different modes of cell death and gene expression
Fitzner R et al. (1995): [Growth behaviour of human leukemia cells]