EIF2AK3 and neoplasm: For example, PERK is highly expressed in a variety of tumor cells, such as kidney renal papillary cell carcinoma, brain lower-grade glioma, breast-invasive carcinoma, and thyroid carcinoma, and the high expression of PERK is associated with poor prognosis, while the high expression in neck squamous cell carcinoma is well correlated with good prognosis [112].