DDIT3 and cancer: ER stress caused by the accumulation of ROS induces the phosphorylation of eIF2α via RNA-dependent protein kinase-like ER kinase, allowing the preferential translation of activating transcription factor-4, which in turn mediates the induction of pro-apoptotic C/EBP homologous protein (CHOP), leading to cancer cell apoptosis 94, 109.