As an important component of the endoplasmic reticulum, PDI is believed to be a marker of poor prognosis in patients with tumors, such as glioblastoma, breast cancer and hepatocellular carcinoma (Shai et al., 2003; Thongwatchara et al., 2011; Xia et al., 2017). The gene discussed is P4HB; the disease is breast cancer.