Targeting 3-Phosphoinoside-Dependent Kinase-1 to Inhibit Insulin-Like Growth Factor-I Induced AKT and p70 S6 Kinase Activation in Breast Cancer Cells
Figure 3
PF-5177624 blocked IGF-I induced cell cycle progression in MCF7 and T47D cells.
Cells were serum-starved for 24 hours in order to synchronize cells at the G0/G1 stage. Cells were pre-treated with DMSO or PF-5177624 for 2 hours prior to addition of IGF-I for 6, 18, 24, 48, or 72 hours. Cells were subsequently harvested, fixed, and stained with PI and cell cycle profiles were obtained by flow cytometry. Bar graphs indicating the percentages of cells in the various cell cycle stages at the 72 hour time point are shown in (A) and (B). Phosphorylation of Histone H3 was determined on cells treated with 5 µM PF5177624 for 24, 48, and 72 hours and normalized to DMSO treatment at the same time points as shown in (C). MCF7 and T47D cells were also incubated with BrdU and subject to FACS to measure incorporation of new DNA. The fold decrease of BrdU incoporation relative to DMSO treatment at the same time point are shown in (D). The t-test was performed to determine if there were differences in samples treated with compound versus DMSO at the same time point; * = p<0.05, ** = p<0.001, *** = p<0.005.