Fig. 5: EZH2 restricts EMP1 expression through up-regulation of promoter histone methylation levels in myeloma cells.

GEO dataset (GSE109673) shows gene expression in RPMI8226 (a) or MM.1S (b) cells treated with or without EZH2 inhibitor OR-S1 (1 μM). c EZH2 mRNA levels in patient-derived myeloma cells (Pt MM) (n = 559) compared to normal plasma cells (n = 22) (GSE2658 and GSE5900). d Correlation of mRNA levels of EZH2 and EMP1 in 30 patients. e Western blotting shows EZH2 and EMP1 expression in normal plasma cells (n = 4) and Pt MM (n = 4). f Expression of EMP1 in RPMI8226 (shCtrl, shEZH2) or MM.1S (Vec, EZH2) cells. g Western blotting shows the expression of EZH2, EMP1 and H3K27me3 in myeloma cells treated with or without DZNep (1 μM). The samples derive from the same experiment but different gels for each protein and processed in parallel (e, g). h Immunofluorescent staining of patient samples with DAPI and antibodies against EZH2, CD138 and EMP1. Scale bar, 10 μm. i ChIP-seq results (GSE214669) for EZH2 and H3K27me3 enrichment in EMP1 gene promoter of MM.1S cells treated with or without EZH2 inhibitors C27 or MS177 (2.5 μM). j–l ChIP assay showing EZH2 and H3K27me3 enrichment in EMP1 gene promoter of Pt MM cells (n = 5) (j), RPMI8226 (k) or MM.1S (l) cells treated with or without DZNep (1 μM). m Correlation of levels of EMP1 and numbers of bone lesion in 30 patients. n EMP1 levels were compared in malignant plasma cells without bone lesions (BL = 0, n = 5) and with bone lesions (BL ≥ 1, n = 25). The cells used in h, m, and n are from the same source as those in Fig. 1b. e–h, k, l are representative of three independent experiments. Data are means ± SD. The correlation was evaluated using Pearson coefficient. r, correlation coefficient. c, f, n: p values were determined by unpaired two-tailed t test; j–l: p values were determined using one-way ANOVA with Tukey’s test. Source data are provided as a Source data file.