Fig 2: EC isolation from mouse muscle(A) Detailed scheme illustrating isolation of ECs from muscle.(B and C) Representative FACS plots for the gating strategy to sort ECs from EDL (B) and soleus (C) muscle based on sorting live/CD45-/CD31+ cells.

Fig 3: CAF-derived IL-1ß upregulates expression of EC adhesion molecules and invasiveness markers. a, b C166 endothelial cells were incubated for 24 h in control medium, medium containing recombinant IL-1ß (5 ng/mL), conditioned medium of MSU-treated WT mammary fibroblasts (Balb/C), or conditioned medium of MSU-treated Il1b-/- fibroblasts. The expression of genes involved in tumour-cell intravasation/extravasation was analysed using qRT-PCR. Representative of three independent experiments. c, d Trans-endothelial migration of mCherry-labelled Met-1 cells supplemented with recombinant IL-1ß (5 ng/mL), conditioned medium of WT NMFs, conditioned medium of Il1b-/- NMFs, or control medium. c Representative images of trans-migrated Met1-mcherry cells. Scale bar, 100 µm. d Quantification of migrating cells per field of view. Representative of two independent experiments. e, f qRT-PCR analysis of the expression of adhesion and migration-related genes in endothelial cells (CD31+CD45-EpCAM-) isolated by FACS from e primary 4T1 tumours or f lungs of tumour-bearing mice. n = pool of six mice per group. Representative of two independent biological experiments. g qRT-PCR analysis of the expression of invasion-related genes in tumour cells (EpCAM+CD45-) isolated by FACS from 4T1 mammary tumours. n = pool of six tumours per group. Results are representative of two independent experiments. In a, b, d data are presented as mean ± s.d. of biological repeats; One-way analysis of variance test followed by Tukey’s multiple comparisons test. In e–g data are presented as mean ± s.d. of technical repeats; Welch’s t-test. Source data are provided as a Source Data file

Fig 4: Snail induces stemness properties and endothelium generation of breast cancer cells through Sox2.a qRT-PCR analysis of relative mRNA expression of Sox2 in MCF-7 and ZR75-1 cells stably infected with lentivirus carrying EV or Snail. b qRT-PCR analysis of relative mRNA expression of Sox2 in MCF-7 and ZR75-1 cells transfected with control siRNA or Snail siRNA. c Representative FACS of MCF-7 cells infected with the indicated plasmids CD44-FITC and CD24-PE. Statistical analysis of CD24-/CD44+ rates is shown in the right panel. Results shown are mean ± SD of three independent experiments. d Mammosphere assay of MCF-7 cells infected with indicated plasmids. Graphs show the relative number of mammospheres. Results shown are mean ± SD of three independent experiments. Scale bar, 20 µm. e qRT-PCR analysis of relative mRNA expression of endothelium markers VEGFR2, CD31, and CD105 in MCF-7 and ZR75-1 cells stably infected with the indicated plasmids. f FACS analysis of MCF-7 cells infected with indicated plasmids using CD31-FITC antibodies. Statistical analysis of CD31+ rates is shown in the right panel. Results shown are mean ± SD of three independent experiments. g Representative confocal images of MCF-7 cells infected with the indicated plasmids labelled with endothelium markers CD31 and VWF. The nuclei were stained with DAPI (blue). Scale bar, 20 µm. Graphs show the percentage of endothelium marker-positive cells. Results shown are mean ± SD of three independent experiments. h Lineage tracing of MCF-7 cells stably infected with EV or Snail using CD31pro-GFP, CD105pro-GFP, or CD144pro-GFP. Scale bar, 10 µm. Graphs show the percentage of GFP-positive cells. Results shown are mean ± SD of three independent experiments. i Tube-forming assays and DiI-AcLDL uptake assays with Snail-copGFP-expressing or copGFP-expressing MCF-7 cells. Statistical analysis of tube length is shown in the right panel. Results shown are mean ± SD of three independent experiments. Scale bar, 100 µm. Red: DiI-AcLDL staining. *P < 0.05, **P < 0.01.

Fig 5: EC isolation from mouse colon(A) Detailed scheme illustrating isolation of ECs from colon.(B) Representative FACS plots for the gating strategy to sort ECs from colon based on sorting live/CD45-/CD31+ cells.