EIF2A and brain cancer: Conversely, when neurocytoma is considered, the phosphorylation of eIF2α has not been found to be associated with benign or malignant brain cancers [129], and in some animal models, inactivating PKR (double-stranded RNA-dependent protein kinase), an upstream kinase of eIF2α through genetic mutation of its catalytic domain, has no effect on cancer progression [10].