scRNA-seq analysis of response to BH3 mimetics. (A) Uniform Manifold Approximation and Projection (UMAP) representation of myeloma cells from 24 control and BH3 mimetics–treated patient samples using scRNA-seq. Mononuclear cells from 23 bone marrow or 1 pleural effusion from patients with MM were cultured overnight with interleukin-6 in the presence, or absence, of 25 nM S63845 and 300 nM venetoclax (BH3 m). Cell processing and scRNA-seq analysis were performed as described in supplemental Materials and methods. Each patient sample is numbered according to supplemental Table 10, and their molecular classification is indicated. (B) Example of individual scRNA-seq analysis of response to BH3 mimetics. (Top left) UMAP split representation of myeloma cells in merged control and treated samples from patient no. 3; cells are colored according to clusters. (Top right) Infer copy number variation (InferCNV) of control and BH3 mimetics–treated cells. InferCNV was calculated using broadinstitute/infercnv package in R in comparison with normal bone marrow plasma cells. (Bottom left) The graphs represent the number of cells per cluster and their proportion in each condition. (Right) Statistical comparison of p53 score in paired clusters (Mann-Whitney U test). Black and red violins indicate no del17p and del17p, respectively. All samples are shown in supplemental Figure 12. (C-D) The p53 score is decreased in cells surviving to BH3 mimetic combination. (C) UMAP representation of p53 score of myeloma cells split into control (left) and treated (right) samples (blue = low; red = high). The p53 score was calculated independently in each patient samples. (D) The graph represents the violin representation of p53 score in 55 114 control cells and 28 077 BH3 mimetic–treated cells from the 24 samples. Statistical analysis was performed using the Mann-Whitney U test. ∗∗∗∗P < .0001; ∗∗∗P < .001; ∗∗P < .01; ∗P < .05.