Fig 2: Identification of endothelial cells in TNBC biopsies. (a) Flow cytometry analysis revealed three endothelial cell subclusters in TNBC biopsied tissues, featured by the expression of ATP1B3, HSPA1B, and KRT7, respectively. Data represent similar results acquired from five independent experiments. (b) UMAP plots showed 9 cell types in the normal human breast and 10 cell types in TNBC biopsy tissues. The boxed cell types indicate endothelial cells. (c) Violin plots exhibited the expression pattern of endothelial cell markers (CD93, CDH5, and PECAM1) and a leukocyte marker (PTPRC). (d) Flow cytometry analysis identified the expression of CDH5 and CD93 from endothelial cells in TNBC biopsies. Data represent similar results acquired from three independent experiments.

Fig 3: Endothelial cells in TNBC biopsies contribute to metastasis. (a) CNET plot shows the DEGS of EC (ATP1B3) and predicts metastasis. (b) CNET plot shows the DEGS of EC (HSPA1B) and predicts metastasis.

Fig 4: scRNA-seq analysis showed three subclusters in breast-associated biopsies. (a) UMAP plot showed integration of endothelial cells isolated from normal breast and TNBC tissues. Three subclusters were identified based on genetic profiles. (b) Violin plots showed the expression pattern of three feature genes ATP1B3, HSPA1B, and KRT7. (c) Immunofluorescent staining of 3 endothelial cell subpopulations: EC (ATP1B3), EC (HSPA1B), and EC (KRT7). Endothelial cells were labelled with CD31. (d) Heatmap showed expression pattern of top 20 genes from each endothelial cell subclusters. (e) Dot plot revealed that each endothelial cell subcluster possesses distinct biological features.