Consistently, when we analyzed RNA-Seq data generated from tumor-infiltrating macrophages isolated from thirteen patients with either endometrial or breast cancer we found a strong correlation between ERN1 and EIF2AK3 (the gene coding for PERK) (correlation coefficient 0.738; p < 0.003), indicative of UPR activation (74). The gene discussed is EIF2AK3; the disease is breast cancer.