Uptake of TAT-BID by PC3 cells. A. Effect of different doses of TAT-BID on PC3 cells viability. Viability of cells treated with TAT-BID for 24 h was measured by MTT test. The average of cells viability (±SD) was shown. B. Time-dependence of the uptake of TAT-BID by PC3 cells. TAT-BID was added to the medium at a concentration of 30 μg/ml. C. Dose-dependence of TAT-BID uptake by PC3 cells. Different doses of TAT-BID were added to the medium for 120 min. TAT-BID and endogenous BID were identified in cell extracts using anti-BID antibodies. GAPDH was used as a loading control. Uptake was expressed as increase in cellular BID (endogenous level of BID was 100%).