Fig. 1.

Identification, expression, and localization of EMP1. a Schematic illustration of the co-culture assay used to identify genes with upregulated expression following the interaction of cancer cells (LNCaP cells) with stroma cells (PrS cells). b Cell morphology and EMP1 expression in LNCaP cells co-cultured with or without PrS cells were observed by immunofluorescence microscopy. Arrowheads: EMP1 expression at the surface of LNCaP cells. Asterisk: PrS cells. DIC: differential interference contrast. Scale bar, 10 μm. c FLAG-EMP1 protein levels in LNCaP cells stably expressing FLAG-EMP1 (FLAG-EMP1-LNCaP cells) were determined by western blotting. d Cell morphology of control and FLAG-EMP1-overexpressing LNCaP cells was examined by light microscopy (bright field). Localization of FLAG-EMP1 in LNCaP cells was determined by confocal microscopy. Arrowheads and arrows indicate the localization of FLAG-EMP1 at the free cell surface and at the cell–cell junction site, respectively. Scale bars, 50 μm and 20 μm in the bright field and immunofluorescence images, respectively. e Lysates from FLAG-EMP1-LNCaP cells were treated with or without glycosidase, followed by western blotting. f Expression levels of EMP1 in several cell lines were analyzed by semi-quantitative PCR and normalized to GAPDH expression