Figure 5.

Oxidative stress underlies the cytotoxic effects of thioalbamide. (a) ROS intracellular levels were measured after thioalbamide treatment of MCF7 cells for 24 and 72 h. Results obtained from cells treated for 6 h with 1 mM H₂O₂, which was used as the positive control, were related to their own control. (b) MCF7 cell viability was assessed after treatment for 72 h with thioalbamide alone or in combination with vitamin E (Vit E) or N-acetyl cysteine (NAC). (c) Total SOD activity assay was performed on MCF7 cells treated with thioalbamide for 24 and 72 h. (d) Immunoblot analysis of SOD1 and SOD2 expression levels in MCF7 cells treated with thioalbamide for 24 and 72 h. GAPDH was used as equal loading control. (e) Quantification of SOD expression levels by densitometry. Thioalbamide treatments were performed at 50 nM. Note that ROS accumulation and oxidative stress underlie the proapoptotic activity of thioalbamide. Values represent the mean ± SD of three independent experiments. *** P value < 0.001; **** P value < 0.0001.