Fig. 3

CQ interrupts PON-induced autophagy and sensitizes neuroblastoma cells to PON-dependent cytotoxicity. a Neuroblastoma cells were pre-treated with CQ for 1 h, and PON was then added for 24 h at the indicated concentrations. Total protein lysates were used for the immunoblotting analysis of the main autophagy regulators p62, LC3, and BECLIN 1. Apoptosis was assessed by means of BCL2, total and cleaved (cl.) PARP, cleaved (cl.) CASPASE 3, and CASPASE 8 proteins. VINCULIN was used as a loading control protein. The molecular weights are indicated in kilodalton (kDa). b Cell metabolic activity assay (MTT) was done in neuroblastoma cells pre-treated with 25 μM of CQ, treated with PON alone, or co-treated (COMBO) with the indicated doses (μM) of drugs for 72 h. Data are normalized to the control samples (100%). Symbols and bars represent the mean ± SEM of three independent experiments