Stat1C alone does not confer sensitivity to Fas-induced apoptosis. U-266-1970 cells and U-266-1970-Stat1C cells were left untreated or were treated with IFN-γ (1000 U/ml) as indicated for 96 hours, followed by a 24 hour incubation with agonistic Fas-antibody CH-11 (FAS) as indicated. The percentage of Annexin V-positive/PI-negative apoptotic cells was evaluated by flow cytometry as described in Materials and Methods. The graph shows the percentage of AnnexinV positive, PI-negative cells, i.e. early apoptotic cells, as a mean of three experiments ± SD.