ATF6 and cancer: To cope with ER stress, cancer-associated cells activate an integrated signaling network known as the unfolded protein responses (UPR), which is characterized by the cleavage of the activating transcription factor 6 (Atf6), priming of the inositol-requiring enzyme 1 alpha (Ire1α), and auto-phosphorylation of the protein kinase R (PKR)-like ER kinase (Perk, encoded by gene Eif2ak3)20.