THBS1 and cancer: In addition, we detected significant upregulation of genes encoding the ECM components thrombospondin-1 (Thbs1) and versican (Vcan) and the ECM regulators vascular endothelial growth factor A (Vegfa), matrix metalloproteinase 9 (Mmp9), and transglutaminase 2 (Tgm2), which are extracellular cross-linkers that stiffen the ECM and are key enzymes involved in cancer cell survival and epithelial–mesenchymal transition [46] (Figure 2A).