Figure 4

Figure 4

Exosomal thrombospondin-1 (TSP1) enhances the transendothelial migration of breast cancer cells. (A) The biological processes revealed by Gene Ontology (GO) analysis of exosomal proteome identified from mass spectral data. The numbers after each column indicated the hit number in each subcategory and p-value in parenthesis. (B) Overlapping of GO enriched biological processes for exosomal proteome related to cell–cell junction. The number of genes contained in each cluster is indicated. (C) TSP1 expression in exosomes derived from parent and gene-transfected breast cancer cells by Western blot analyses. (D) Transendothelial migration of MDA-MB-231 after treating HUVECs with exosomes derived from breast cancer cells differentially expressing TSP1. Scale bar, 100 μm. (E) Quantitative analyses of the migrated MDA-MB-231 cells in transwell assay. Data are shown as mean ± SD and representative of three independent experiments. ** p < 0.01, *** p < 0.001 by unpaired Student’s t-test.