Study type: Medical/biological study (experimental study)

Extremely low frequency electromagnetic fields affect proliferation and mitochondrial activity of human cancer cell lines. med./bio.

Published in: Int J Radiat Biol 2015; 91 (12): 964-972

Aim of study (acc. to author)

The effects of exposure of different human cancer cell lines to a 50 Hz magnetic field on cell proliferation and the mitochondrial activity should be investigated.

Background/further details

For each exposure duration and each treatment, a separate control group was used (remark EMF-Portal: no details were given on procedure for controls).

Endpoint

Exposure

Exposure Parameters
Exposure 1: 50 Hz
Exposure duration: continuous for 3, 6 or 7 days

Exposure 1

Main characteristics
Frequency 50 Hz
Type
Waveform
  • rectangular
Exposure duration continuous for 3, 6 or 7 days
Exposure setup
Exposure source
Chamber cell culture dishes between coils in a box inside an incubator; the box shielded the cells and exposure apparatus from the background magnetic field and was made of stainless steel and the shield was made of a 2 mm thick inner layer of mu-metal and an outer layer made of a special aluminium-free alloy
Setup setup was composed of two independent couples of coaxial coils made of 200 loops (formed of copper wire, 0.3 mm in diameter) in the shielding box, each loop being 2.5 cm in length (with a resulting loop density of 8000 loops per meter) and wound into a tightly packed plastic frame; the frame had a cylindrical shape with an outer radius of 8 cm and the distance between the two coaxial coil couples was 8 cm; the cell culture dish was placed in the central part between the coils; the outer coils were supplied with a DC current and provided a static magnetic field of 45 µT to simulate the geomagnetic field; the inner coils (7.5 cm radius) were connected to an AC current generator (signal with a duty cycle of 50%); inside the box, the temperature and humidity were homogenous to the rest of the incubator
Additional info the residual magnetic field inside the shielding box measured around 1-2 µT
Parameters
Measurand Value Type Method Mass Remarks
magnetic flux density 12 µT effective value - - -

Exposed system:

Methods Endpoint/measurement parameters/methodology

Investigated system:
Time of investigation:
  • after exposure

Main outcome of study (acc. to author)

Proliferation was significantly decreased in all exposed cell lines compared to the control groups.
Mitochondrial activity was significantly increased in SKBR3 and HT29 cells directly after exposure for 3 or 7 days. However, the effects were reversible as further cultivation without exposure negated the effect. The ATP level and the gene expression in mitochondria were not changed significantly by exposure to the magnetic field.
Protein expression of phosphorylated ERK, p53 and cytochrome C was significantly reduced in mitochondria of exposed SKBR3 cells compared to the control groups after 3 and 7 days of exposure.
All other parameters did not show significant differences between exposure and control groups.
The authors conclude that exposure of different human cancer cell lines to a 50 Hz magnetic field might reduce cell proliferation, possibly mediated by the modulation of mitochondrial activity.

Study character:

Study funded by

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