HSPA5 and neoplasm: Liu et al observed that downregulation of the ERS indicator protein HSPA5 significantly reduced the invasive capacity of tumor cells by inhibiting phosphatidylinositol 3-kinase/AKT signaling.[43] Epithelial mesenchymal transition (EMT) has an important role in tumor development, and Zeindl-Eberhart et al found that EMT causes ERS.