MMP9 and hepatocellular carcinoma: Specifically, through secretion of growth factors such as vascular endothelial growth factor A (VEGFA) and via deposition of extracellular matrix (ECM) components such as matrix metalloproteinase 9 (MMP9), TAMs can contribute to neovascularization during HCC (Zhang et al., 2023), but might also enable immunosuppression (e.g., increased Tregs recruitment, inhibition of CD8+ T cell cytotoxicity) through C-C motif ligand (CCL)20 signaling (Wu et al., 2019).