Fig. 2.
Induction of apoptosis in LAMA84 and LAMA84R cells.
Cells (0.5 × 106) were incubated with 1 μM STI571 and cultured over 28 hours. After the addition of annexin V and propidium iodide, samples were immediately submitted to double fluorescence analysis. In the sensitive LAMA84 line, STI571 committed 27.1% of cells to early apoptosis (2B) while in the nontreated sample (A), only 2.2% were found in the respective fraction. In addition, the late apoptotic fraction in the sensitive sample (36.3%) (B) also exceeded the nontreated control (10.5%) (A). In the resistant LAMA84R cells, both the early (4.8%) and the late (7.9%) apoptotic fraction of the treated sample did not significantly exceed the nontreated sample (3.6% and 4.6%, respectively) (C) and (D).