EIF2AK3 and breast cancer: As a rationale, the inhibition of PERK signaling reversed the multidrug resistance of de-differentiated breast cancer cells (Del Vecchio et al., 2014), and the inhibition of the eIF2α-dependent arm of UPR reversed the tumor radioresistance in a subset of hypoxic glioblastoma cells (Rouschop et al., 2013).