FIG. 3.

Effects of actin inhibitors. A375SM-Luc705-B cells (150,000/well) were preincubated with (A) cytochalasin D or (B) latrunculin A at the indicated concentrations for 1 hour at 37°C in OPTI-MEM containing 1% FBS. At that point, 623-Tamra (100 nM) or RGD-623-Tamra (100 nM) were added to the wells, and the cells were treated for 24 hours. The cells were washed with PBS, and lysed with 1× reporter lysis buffer (150 μL). The cell extracts were frozen and thawed, vortexed, and centrifuged. Relative fluorescent units (RFUs) were measured using a microfluorimeter. The uptake data was normalized on protein concentration. Results represent means and standard deviations of triplicate determinations. Uptake was considered as 100% where no inhibitor was added.