Fig. 4: IFN-inducible signature is correlated between CD138+ and microenvironment cells, and gene signatures exhibit intratumor heterogeneity.

a Mean activity ± s.e.m. of CD138+ IFN-inducible signature across normal and abnormal plasma cell populations. Both normal and abnormal plasma cells exhibit significantly increased activity of the interferon-inducible signature in MM vs. NBM (q = 5.2 × 10⁻³ and q = 3.2 × 10⁻⁴, resp.). Source data are provided as a Source Data File. b Mean activity per sample of IFN-inducible signature discovered in CD138+ cells (top), T cells (middle) and CD14+ monocytes (bottom). Mean expression levels for the ten genes with the highest values in the W matrix for each signature are also shown. Expression of additional interferon-inducible genes IFI27 and IFI6 is shown for CD138+ samples (see Supplementary Note 2). CD138+ samples from patients were limited to abnormal cells before calculating means. NMF signature results and expression data for T cells and monocytes were taken from Zavidij et al.¹⁷. c Subpopulations within patient tumors heterogeneously express gene signatures. Cells from a given MM sample were projected onto a UMAP plot based on expression of highly variable genes, and colored by the activity level of NMF signatures determined to be heterogeneously expressed in that sample (see Methods).