ZEB1 and cancer: Using normal immortalized human epithelial cell lines and primary epithelial cells, Mikaelian and colleagues [40] showed that genetic and pharmacologic inhibition of mTORC1 triggers EMT associated with upregulation of ZEB1, known to activate EMT, but these effects are not found in cancer-driven cell lines including the MDA-MB-231 breast cancer cell line as we used in this study.