Figure 1

Severe nitrosative stress reduces cell proliferation in breast cancer cells. (A) Cells were exposed to the indicated treatments and cell proliferation was determined after 48 or 72 hours. Cell proliferation expressed as the percentage of untreated cells. *P < 0.05, compared with untreated. #P < 0.05, compared with S-nitrosocysteine (CSNO) treated. (B) Cell lysates from MCF-7 cells, pretreated or not with auranofin (Aur), and subjected to the indicated treatments were analyzed with the biotin switch assay for the detection of S-nitrosylated proteins. The corresponding densitometric analysis of the total protein bands detected in the biotin switch assay (normalized to the signal of Ponceau S stain) is also shown. Data are means ± standard error of the mean of three independent experiments. Significant augmented protein S-nitrosylation (P < 0.05) was observed comparing CSNO and Aur + CSNO with untreated cells.