<p>(A, B) Expression of DR5 is shown in five melanoma cell lines in response to TRAM-34 (40 µM, +), and (C, D) expression of DR4 is shown in A-375 and A-375-TS, as compared to DMSO-treated controls (−). Total protein expression was determined by Western blotting, and surface expression was determined by flow cytometry. (E) Expression of DcR1 and DcR2 is shown by flow cytometry in five melanoma cell lines in response to TRAM-34. HeLa and SW480 cells served as positive controls for DcR1 and DcR2, respectively. IgG1-stained cells served as negative controls. Three (A, C) or two (E) independent experiments, with each time triplicates revealed highly similar results. (F) Apoptosis in response to TRAM/TRAIL was monitored in A-375 and Mel-HO after blocking DR4 and/or DR5 by selective antagonistic antibodies (mean values and SDs of two independent experiments, each one with triplicates). Statistical significance is indicated (*; p<0.005), when comparing combined treatment with TRAIL alone.</p
