Transcriptomic signature of BPDCN. (A) Expression levels of SIGLEC6 probes on microarray. (B) Main gene ontology pathways deregulated for each type compared with BPDCN, using hypergeometric probability score with 20 HM and P = .05. Downregulated pathways are light blue, and upregulated pathways are yellow to bright red. (C-F) GSEA examples of gene sets enriched in BPDCN compared with AML (C) or T-ALL (D-F). (G-H) Principal component analysis based on published signatures differentiating BPDCN from pDCs (panel G: Sapienza et al²⁶ ; panel H: Villani et al⁷ ). (I) Heatmap depicting the expression levels of selected upregulated (red) or downregulated (blue) genes in BPDCN compared with normal pDCs. In the dot plot, the 12 BPDCN are depicted in magenta, patient P13 in gray, AML in purple, B-ALL in green, T-ALL in yellow, and normal pDC in light blue.