NR4A1 and triple-negative breast carcinoma: In this study, we investigated how wild-type (WT) Ngb and its two mutants, C120S Ngb, in which Cys120 is replaced by serine, and A15C Ngb, which contains an engineered Cys15-Cys120 disulfide bridge, modulate oxidative stress in triple-negative breast cancer (MDAMB231) and hormone receptor-positive breast cancer (MCF-7) cells.