Fig. 1.
Rapid induction of apoptosis by culture of MM cells in the presence of actinomycin D.
MM cell lines were cultured in RPMI/10% FBS plus IL-6 (1 ng/mL) and actinomycin D (1 μg/mL) for the times indicated. (A) Aliquots of cells were removed and protein extracts assayed for caspase activity by means of the fluorogenic substrate DEVD-AMC. (B) Cytospin preparations were prepared at the times indicated, and TUNEL assays were performed.