Since the ER membrane and mitochondrial membrane are in close contact during cell stresses (Bravo-Sagua et al., 2013), we first investigated whether the ER protein STING1 can be translocated to mitochondria in PANC1, a human pancreatic ductal adenocarcinoma (PDAC) cell line that expresses STING1 and is sensitive to ferroptosis (Zhu et al., 2017; Li C. et al., 2020). Here, STING1 is linked to pancreatic ductal adenocarcinoma.