Dose-dependent cleavage of caspase-8 by mitomycin C, daunorubicin, and doxorubicin. Jurkat and Jurkat-R cells (1 × 10⁶) were stimulated with mitomycin C (25 μg/mL lanes 4,8; 12.5 μg/mL lanes 3,7; 6.25 μg/mL lanes 2,6; diluent control lanes 1,5; for 6 hours), daunorubicin (5 μg/mL lanes 4,8; 2.5 μg/mL lanes 3,7; 1.25 μg/mL lanes 2,6; diluent control lanes 1,5; for 10 hours) or doxorubicin (2 μg/mL lanes 4,8; 1 μg/mL lanes 3,7; 0.5 μg/mL lanes 2,6; diluent control lanes 1,5; for 10 hours). Whole cell lysates were immunoblotted with anti-caspase-8 as described in Fig 5A. Filled arrowheads (◂) indicate the cleaved intermediate forms of caspase-8a and caspase-8b.