ATF4 and pancreatic neoplasm: Activating transcription factor 4 (ATF4) participates in heat shock protein family A member 5 (HSPA5) expression and upregulation of solute carrier family 7 member 11 (SLC7A11) to inhibit ferroptosis, thus enhancing the resistance of pancreatic cancer cells or glioma cells to ferroptosis caused by gemcitabine or dihydroartemisinin (Dixon et al. 2014).