Baseline physiologic/prosurvival UPR gene expression in WM disease. UPR gene expression in BM CD19⁺ WM cells (N = 16) was compared with BM CD19⁺ cells from healthy donors (NBM, N = 4) using relative quantitative RT-PCR (qPCR). Panels show mean gene expression as a normalized ratio over ribosomal 18S. (A) Expression of genes of the PERK pathway, including PERK and GADD34. (B) Expression of genes of the ATF6 pathway, including ATF6, GRP78/BiP, and Xbp1. All data represent mean plus or minus SD of triplicate experiments. (C) Panel that summarizes the mean values for the transcript levels with SD and range.