Expression of endothelial protein C receptor in normal and malignant prostate cells. (A) Agarose gel electrophoresis with ethidium bromide-stained amplificates of EPCR and GAPDH-specific mRNA in normal prostate epithelial cells and prostate cancer cell lines. M, 100 bp molecular weight ladder; PrEC, prostate epithelial cells; LN, LNCaP cells; and DU, DU-145 cells. Numbers at the top of the images represent the ratio of EPCR/GAPDH mRNA calculated from the densitometry values of amplificates. Data are representative of three independent experiments giving similar results. (B) Flow cytometry analysis of EPCR immunoreactivities in prostate cells. Cells were incubated with anti-EPCR RCR-252 monoclonal antibodies followed by incubation with FITC-conjugated secondary antibodies and fixation of cells. Black shading represents tracks obtained with specific primary antibodies; gray shading shows control cells treated with corresponding isotype IgG. Values at the bottom of images represent the mean fluorescence intensities (MFI) corrected for values in related controls. Results are the means ± SDs of analyses in duplicates obtained in three similar experiments.