Figure 2. Concentration-dependent effects
of imatinib on caspase-3/PARP cleavage and Akt phosphorylation.
Subconfluent RGC-5 cells were maintained in serum free medium (-FBS)
for 24 h or 48 h, during which time the cells were exposed to
increasing concentrations of imatinib (10 µM to 30 µM). The cell
lysates were subjected to immunoblot analysis using primary antibodies
specific for A) caspase-3 that detects full-length and cleaved
caspase-3, and B) PARP that detects full-length PARP and
cleaved PARP, and C) phospho-Akt(Ser473) and total Akt. To
normalize the expression of cleaved caspase-3 and cleaved PARP and the
phosphorylation of Akt, we used the housekeeping gene β-actin as an
internal control. The respective bar graphs shown are the mean±SEM
values from 3 to 5 experiments. The asterisk and the sharp (hash mark)
indicate a p<0.05 compared with the respective controls.