COL1A1 and breast cancer: The hub genes in the group of low-grade BC cell-derived EVs versus normal cell-derived EVs include fibronectin 1 (FN1) 34, interleukin 1 beta (IL1B) 35, collagen type I alpha 1 chain (COL1A1) 36, collagen type I alpha 2 chain (COL1A2) 37, platelet and endothelial cell adhesion molecule 1 (PECAM1) 38, von Willebrand factor (VWF) 39, kinase insert domain receptor (KDR) 40, decorin (DCN) 41, platelet-derived growth factor receptor beta (PDGFRB) 42, and insulin like growth factor 1 (IGF1) 43,44, all of which were significantly upregulated (Figure 2G).