Figure 1.

Quantification of cystine acquisition in MDA-MB-231 cells in the presence of capsazepine (CPZ).

Notes: CPZ inhibits the uptake of ¹⁴C-cystine when incubated with 0–50 μM of the compound. This effect is comparable to intracellular levels of ¹⁴C-cystine after incubation with sulfasalazine, a known system x_c⁻ inhibitor. Data are expressed as the fold change in counts per minute/mg protein (±standard error of the mean) relative to vehicle control (dimethyl sulfoxide). **P<0.01; ***P<0.001; ****P<0.0001.