Cell surface expression of urokinase receptor in normal mammary epithelial cells and breast cancer cell lines.
BACKGROUND
The urokinase receptor (uPAR) is important in the process of extracellular matrix degradation occurring during cancer cell invasion and metastasis. We wished to quantify uPAR on the surfaces of normal mammary epithelial cells (HMEC) and 6 well-known breast cancer cell lines using flow cytometry.


METHODS
Cell surface uPAR was labelled with a monoclonal antibody, and this was detected with a fluorescent-labelled second antibody and accurately measured using flow cytometry. The measured fluorescent signals of the stained cells were interpolated with those of Quantum Simply Cellular bead standards to determine the number of uPAR sites per cell.


RESULTS
The breast cancer cell lines ranged from 13,700 to 50,800 uPAR sites per cell, whilst HMEC cells had only 2,500 sites.


CONCLUSIONS
This simple and reliable method showed that the expression of cell surface uPAR is higher in the breast cancer cell lines than in the normal mammary cells.
Li
Y
Y
Department of Surgery, North Queensland Clinical School, University of Queensland, Townsville, Australia.
Wood
N
N
Yellowlees
D
D
Donnelly
P K
PK
D000818:Animals; D001940:Breast / Q000737:chemistry*; D001943:Breast Neoplasms / Q000737:chemistry*; D004847:Epithelial Cells / Q000737:chemistry; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000737:chemistry; D051379:Mice; D011956:Receptors, Cell Surface / Q000032:analysis*; D055293:Receptors, Urokinase Plasminogen Activator; D014407:Tumor Cells, Cultured
C524898:PLAUR protein, human; C524899:Plaur protein, mouse; D011956:Receptors, Cell Surface; D055293:Receptors, Urokinase Plasminogen Activator