Automated electrorotation to reveal dielectric variations related to HER-2/neu overexpression in MCF-7 sublines.
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.
Cristofanilli
Massimo
M
Department of Breast Medical Oncology, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA. mcrisdtof@mdanderson.org
De Gasperis
Giovanni
G
Zhang
Lisha
L
Hung
Mien-Chie
MC
Gascoyne
Peter R C
PR
Hortobagyi
Gabriel N
GN
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
D018719:Erb-b2 Receptor Tyrosine Kinases