eIF2α phosphorylation: A hallmark of immunogenic cell death

Immunogenic cell death (ICD) induced by anticancer chemotherapeutics is usually preceded by premortem stress affecting the endoplasmic reticulum (ER). This ER stress does not reflect a canonical unfolded protein response (UPR) but rather manifests solely at the level of the phosphorylation of eIF2 alpha. eIF2 alpha phosphorylation is hence a quintessential hallmark of ICD that can be detected by immunohistochemistry in tumor samples.