Cytotoxicity and activation of caspase 3 on HL60 cells by violacein is prevented by infliximab. The graphs show the effects of violacein and IFX on and MTT reduction (A) and cell number (B). In the absence of compounds, the MTT reduction was considered as 100%. All experiments were performed in a 24-well plate. Results represent the means ± standard error of 3 experiments run in triplicates (P < .05). (C) Cellular lysates were extracted from HL60 cells treated with 1000 nM violacein (V), V 1000 nM + IFX 100 μg/mL, TNF 100 pg/mL, or TNF 100 pg/mL + IFX 100 μg/mL. Western blot analysis was performed to assess the active caspase 3.