Scanning electrochemical microscopy of living cells: different redox activities of nonmetastatic and metastatic human breast cells.
Electrochemical methods have been widely used to monitor physiologically important molecules in biological systems. This report describes the first application of the scanning electrochemical microscope (SECM) to probe the redox activity of individual living cells. The possibilities of measuring the rate and investigating the pathway of transmembrane charge transfer are demonstrated. By this approach, significant differences are detected in the redox responses given by nonmotile, nontransformed human breast epithelial cells, breast cells with a high level of motility (engendered by overexpression of protein kinase Calpha), and highly metastatic breast cancer cells. SECM analysis of the three cell lines reveals reproducible differences with respect to the kinetics of charge transfer by several redox mediators.
Liu
B
B
Department of Chemistry and Biochemistry, Queens College of the City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367, USA.
Rotenberg
S A
SA
Mirkin
M V
MV
D000818:Animals; D001940:Breast / Q000502:physiology / Q000648:ultrastructure; D001943:Breast Neoplasms / Q000503:physiopathology* / Q000648:ultrastructure; D002417:Cattle; D002460:Cell Line; D002462:Cell Membrane / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D002465:Cell Movement; D018914:Cells, Immobilized / Q000502:physiology / Q000648:ultrastructure; D004563:Electrochemistry / Q000295:instrumentation / Q000379:methods; D004847:Epithelial Cells / Q000502:physiology / Q000648:ultrastructure; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000235:genetics / Q000378:metabolism; D008855:Microscopy, Electron, Scanning / Q000295:instrumentation / Q000379:methods*; D009285:Naphthoquinones / Q000494:pharmacology; D009362:Neoplasm Metastasis; D010084:Oxidation-Reduction; D011493:Protein Kinase C / Q000235:genetics / Q000378:metabolism; D051571:Protein Kinase C-alpha; D014162:Transfection; D014407:Tumor Cells, Cultured; D014812:Vitamin K / Q000494:pharmacology
D007527:Isoenzymes; D009285:Naphthoquinones; D014812:Vitamin K; C040756:1,2-naphthoquinone; C496628:PRKCA protein, human; D011493:Protein Kinase C; D051571:Protein Kinase C-alpha