In view of the CHOP‐induced ERO1 levels and the beneficial cytotoxic activity of ISRIB in some cancers, we tested whether ISRIB also inhibited ERO1 in preclinical models of breast cancers (Ghaddar et al., 2021; Jewer et al., 2020; Nguyen et al., 2018). This evidence concerns the gene DDIT3 and cancer.