Figure 2

Prostate cancer-derived cell lines are sensitive to killing by the HOX /PBX antagonist HXR9. (a) HXR9 enters the cytoplasm and nuclei of PC3 cells in vitro. PC3 cells were incubated with 5 μM FITC labelled HXR9 (green) for two hours and then stained with Hoechst S769121 (a fluorescent dye staining nuclei yellow). Scale bar: 20 μm (b-d) Light micrographs of PC3 cells either untreated (b) or incubated with 60 μM CXR9 (c) or HXR9 (d) for two hours. Scale bar: 100 μm (e) Survival curves for PC3, DU145, LNCaP and WPMY-1 cells treated with HXR9. (f) IC50 values for HXR9 treatment. The negative control peptide CXR9 was not toxic at any of the concentrations tested for any of the cell lines (i.e. the IC50 > 100 μM). Error bars represent the SEM (n = 3), the p values are with respect to WPMY-1.