Knocking down either PERK or IRE1A partially abrogated NMT1 knockdown-mediated decrease of ALDH-positive cell population and mammosphere formation (Figs. 2j,k and S2J, S2K), and partially abrogated NMT1 knockdown-mediated inhibition of migration and invasion in breast cancer cells (Figs. 2m,N and S2M, S2N). This evidence concerns the gene ERN1 and breast cancer.