There is increasing evidence that PDI plays a role in cancer survival and progression through its regulation of ER stress, apoptosis, DNA repair, and autophagy, by inhibiting autophagy through its thioredoxin 6 domain, and PDI enhances the resistance of tumor cells to radiotherapy and chemotherapy by decreasing autophagy through the ERS pathway [35, 36]. The gene discussed is P4HB; the disease is cancer.