Figure 4. Inhibition of autophagy and JNK increases the Bortezomib anti-proliferative effect in BC3 and BCBL1 PEL cells.

(A) Viability assay evaluated by trypan blue exclusion was performed in BC3 (left panel) and BCBL1 (right panel) cells treated with bortezomib (20 nM) or 3-MA (5 mM) alone or in combination for 16 hrs. Mean ± the standard deviation was also indicated (n = 3 experiments). * p-value  =  0.05, ** p-value  =  0.02. Western blotting analysis was performed on BC3 cells to evaluate the expression of cleaved (cl) PARP p85 fragment (middle panel). β-actin was used as loading control. (B) BC3 and BCBL1 cells were transfected with ATG5 siRNA or scramble siRNA (siRNASc), and than a western blot was performed with the anti-ATG5 antibody. β-actin was used as loading control. Viability assay evaluated by trypan blue exclusion was performed in BC3 and BCBL1 cells ATG5 or scramble-knocked down upon bortezomib treatment (20 nM) for 16 hrs. Mean ± the standard deviation was indicated (n = 3 experiments). ♦ p-value  =  0.02, ♦♦ p-value  =  0.03. Western blotting analysis was also performed on BC3 cells to evaluate the expression of PARP p85 fragment (cl PARP) and β-actin was used as internal control. (C) Cells viability assay on BC3 and BCBL1 cells treated with bortezomib (20 nM) and SP600125 (20 µM) alone or in combination for 16 hrs. The percentage of live cells was evaluated by trypan blue exclusion assay. Mean ± the standard deviation was indicated (n = 3 experiments). p-value  =  0.01, p-value  =  0.01. Western blotting analysis was performed on BC3 cells to evaluate the expression of PARP p85 fragment (cl PARP) and β-actin was used as loading control.