Proteasome inhibition with bortezomib activates autophagy in Raji cells. (A) Raji cells were incubated with bortezomib at indicated concentrations for 24 or 48 hours. Then, total cell lysates were prepared and Western blot analysis was performed using anti-LC3B antibody against LC3B-I and LC3B-II fragments. (B) Densitometric analysis of LC3B-II to LC3B-I ratio using the Quantity One 4.6.6 software. (C) Raji cells were incubated with indicated concentrations of bortezomib for 24 or 48 hours. Then, cells were stained with 1 μg/mL acridine orange for 15 minutes, washed with PBS, and analyzed in a FACSCalibur using CellQuest Pro Software Version 5.2 (Bio-Rad).