MMP9 and neoplasm: Subsequently, we performed IHC staining analysis of VM-related markers, including VM markers VE-cadherin, Fibronectin 1 (FN1), SERPINE2, tumor microenvironment markers MMP2 and MMP9, epithelial cell marker E-cadherin and mesenchymal cell marker vimentin (Figure 1J-K and Figure S1A-B).