Figure 2.
Fas-induced apoptosis in the DLD1 colon carcinoma cell line transfected with the variant p42-ETS1 protein. DLD1 cells transfected with p42-ETS1 (ΔVII-19), control vector (tTA1), and p51-ETS1 (E1–10) were cultured in 10% serum, in RPMI 1640 medium without tetracycline. After 18-hr treatment with anti-Fas antibody CH-11 (100 ng/ml), 5 × 105 cells were collected and fixed in 75% ethanol before staining with propidium iodide. DNA content was analyzed by fluorescence-activated cell sorting. Peak sub-G1 indicates early apoptotic cells.