title: Automated electrorotation to reveal dielectric variations related to HER-2/neu overexpression in MCF-7 sublines.
abstract: OBJECTIVE
  Electrorotation (ROT) is a technique that allows for determination of the dielectric properties of living cells when exposed to a rotating electric field. We evaluated the ROT behavior of MCF/neo and p185(neu) transfectancts MCF/HER2-11 and MCF/HER2-18 to investigate whether differences in HER-2/neu expression were associated with differences in dielectric properties in these cells.
  
  
  METHODS
  P185(neu) was measured by Western blotting in MCF/neo cells and HER-2/neu transfectants MCF/HER2-11 and MCF/HER2-18. ROT spectra and cell membrane-specific capacitance were obtained for each cell line.
  
  
  RESULTS
  The mean cell membrane-specific capacitance values for MCF/neo, MCF/HER2-11, and MCF/HER2-18 were 2.09, 1.70, and 2.56 microF/cm(2), respectively. The mean specific capacitance for MCF/neo was significantly different from that for MCF/HER2-11 (P = 0.006) and that for MCF/HER2-18 (P = 0.007).
  
  
  CONCLUSIONS
  ROT is sufficiently sensitive to detect variations in dielectric properties in breast cancer cell lines overexpressing p185(neu). These differences may be related to the morphological alterations determined by HER-2/neu overexpression.
authors.affiliation: Department of Breast Medical Oncology, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA. mcrisdtof@mdanderson.org
authors.forename: Massimo
authors.initials: M
authors.lastname: Cristofanilli
authors.forename: Giovanni
authors.initials: G
authors.lastname: De Gasperis
authors.forename: Lisha
authors.initials: L
authors.lastname: Zhang
authors.forename: Mien-Chie
authors.initials: MC
authors.lastname: Hung
authors.forename: Peter R C
authors.initials: PR
authors.lastname: Gascoyne
authors.forename: Gabriel N
authors.initials: GN
authors.lastname: Hortobagyi
mesh_terms: D001331:Automation; D001703:Biophysics / Q000379:methods*; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000378:metabolism*; D004553:Electric Conductivity; D006801:Humans; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis*; D012680:Sensitivity and Specificity; D014162:Transfection; D014407:Tumor Cells, Cultured
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases