Gene expression in human breast epithelial cells exposed to 60 Hz magnetic fields.

Epidemiology suggests a possible relationship between exposure to power frequency magnetic fields (EMF) and breast cancer. One mechanism through which EMF could stimulate breast cancer induction is via altered expression of oncogenes and/or tumor suppressor genes that regulate normal and neoplastic growth. To evaluate the hypothesis that EMF action in the breast is mediated by alterations in gene expression, transcript levels of c-myc and a battery of other cancer-associated genes were quantitated in human breast epithelial cells exposed to pure, linearly polarized 60 Hz EMF with low harmonic distortion. HBL-100 cells and normal (non-transformed) human mammary epithelial cells were exposed to EMF flux densities of 0.1, 1.0 and 10.0 Gauss (G) for periods ranging from 20 min to 24 h; concurrent sham controls were exposed to ambient fields (<0.001 G) only. Gene expression was quantitated using ribonuclease protection assays. EMF exposure had no statistically significant effect on basal levels of c-myc transcripts in either human breast cell model, and had no effect on alterations in c-myc expression induced by 12-O-tetradecanoylphorbol-13-acetate. Transcript levels of c-erbB-2, p53, p21, GADD45, bax, bcl-x, mcl-1, and c-fos were also unaffected by EMF exposure. These results suggest that EMF is unlikely to influence breast cancer induction through a mechanism involving altered expression of these genes.

[1]  S J Thurston,et al.  Short exposures to 60 Hz magnetic fields do not alter MYC expression in HL60 or Daudi cells. , 1995, Radiation research.

[2]  R. Owen.  MYC mRNA abundance is unchanged in subcultures of HL60 cells exposed to power-line frequency magnetic fields. , 1998, Radiation research.

[3]  J. Yokota,et al.  Proto-oncogene abnormalities in human breast cancer: correlations with anatomic features and clinical course of disease. , 1987, Journal of clinical oncology : official journal of the American Society of Clinical Oncology.

[4]  J. B. Andersen,et al.  Incidence of cancer in persons with occupational exposure to electromagnetic fields in Denmark. , 1993, British journal of industrial medicine.

[5]  A. Lacy-Hulbert,et al.  No effect of 60 Hz electromagnetic fields on MYC or beta-actin expression in human leukemic cells. , 1995, Radiation research.

[6]  W. Kaune.  Assessing human exposure to power-frequency electric and magnetic fields. , 1993, Environmental health perspectives.

[7]  R. Lidereau,et al.  Genetic alteration of the c-myc protooncogene (MYC) in human primary breast carcinomas. , 1986, Proceedings of the National Academy of Sciences of the United States of America.

[8]  K. Bland,et al.  Oncogene Protein Co‐Expression Value of Ha-ras, c-myc, c-fos, and p53 as Prognostic Discriminants for Breast Carcinoma , 1995, Annals of surgery.

[9]  Z. Shao,et al.  p21/waf1/cip1 and mdm‐2 expression in breast carcinoma patients as related to prognosis , 1997, International journal of cancer.

[10]  G Thériault,et al.  Occupational and residential 60-Hz electromagnetic fields and high-frequency electric transients: exposure assessment using a new dosimeter. , 1988, American Industrial Hygiene Association journal.

[11]  T. Soussi,et al.  Epithelial HBL-100 cell line derived from milk of an apparently healthy woman harbours SV40 genetic information. , 1985, Experimental cell research.

[12]  T B Wenzl,et al.  Occupational Exposure to 60‐Hertz Magnetic Fields and Risk of Breast Cancer in Women , 1996, Epidemiology.

[13]  M. Lindstrom,et al.  ApcMin, a mutation in the murine Apc gene, predisposes to mammary carcinomas and focal alveolar hyperplasias. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[14]  J. Hillion,et al.  Effects of 50 Hz magnetic fields on C-myc transcript levels in nonsynchronized and synchronized human cells. , 1995, Bioelectromagnetics.

[15]  A. Harris,et al.  bcl-2 in normal human breast and carcinoma, association with oestrogen receptor-positive, epidermal growth factor receptor-negative tumours and in situ cancer. , 1994, British Journal of Cancer.

[16]  Cori Bargmann,et al.  The neu oncogene encodes an epidermal growth factor receptor-related protein , 1986, Nature.

[17]  T. Tynes,et al.  Incidence of cancer in Norwegian workers potentially exposed to electromagnetic fields. , 1992, American journal of epidemiology.

[18]  C. Osborne,et al.  bcl‐2 and apoptosis in lymph node positive breast carcinoma , 1998, Cancer.

[19]  Transcription and translation in cells exposed to extremely low frequency electromagnetic fields , 1991 .

[20]  G. Matanoski,et al.  Electromagnetic field exposure and male breast cancer , 1991, The Lancet.

[21]  R. Shiu,et al.  Stimulation of c-myc oncogene expression associated with estrogen-induced proliferation of human breast cancer cells. , 1987, Cancer research.

[22]  K. Keyomarsi,et al.  Redundant cyclin overexpression and gene amplification in breast cancer cells. , 1993, Proceedings of the National Academy of Sciences of the United States of America.

[23]  C. Davis,et al.  Rodent cell transformation and immediate early gene expression following 60-Hz magnetic field exposure. , 1996, Environmental health perspectives.

[24]  K. McKenzie,et al.  Animal models for breast cancer. , 1995, Mutation research.

[25]  Lack of a co-promoting effect of a 60 Hz magnetic field on skin tumorigenesis in SENCAR mice. , 1998, Carcinogenesis.

[26]  W Godolphin,et al.  Studies of the HER-2/neu proto-oncogene in human breast and ovarian cancer. , 1989, Science.

[27]  V. Kosma,et al.  Apoptosis suppressing protein bcl‐2 is expressed in well‐differentiated breast carcinomas with favourable prognosis , 1995, The Journal of pathology.

[28]  A. Shirley‐Henderson,et al.  EXPOSURE OF HUMAN CELLS TO ELECTROMAGNETIC FIELDS: EFFECT OF TIME AND FIELD STRENGTH ON TRANSCRIPT LEVELS , 1992 .

[29]  A. Børresen-Dale,et al.  Interaction between bcl‐2 and p21 (WAF1/CIP1) in breast carcinomas with wild‐type p53 , 1997, International journal of cancer.

[30]  D A Savitz,et al.  Breast cancer mortality among female electrical workers in the United States. , 1994, Journal of the National Cancer Institute.

[31]  W. R. Adey,et al.  Magnetic field-induced changes in specific gene transcription. , 1992, Biochimica et biophysica acta.

[32]  C. Johansen,et al.  Risk of cancer among Danish utility workers--a nationwide cohort study. , 1998, American journal of epidemiology.

[33]  J. Foekens,et al.  Growth Factors , 1993, Annals of the New York Academy of Sciences.

[34]  P. Demers,et al.  Occupational exposure to electromagnetic fields and breast cancer in men. , 1991, American journal of epidemiology.