Additional microenvironment targets include CD206, CD163, translocator protein (TSPO), and folate receptor beta (FRβ) on tumor-associated macrophages; αvβ3 integrin, APN/CD13, vascular endothelial growth factor (VEGF), and PSMA on neo-angiogenic endothelial cells; programmed cell death protein-1 (PD-1), programmed death-ligand 1 (PD-L1), chemokine receptor type 4 and 12 (CXCR4/CXCL12) in tumor-infiltrating immune cells; and fatty acid-binding protein 4 (FAB4), and fatty acid synthase (FASN) on cancer-associated adipocytes 39. Here, TSPO is linked to cancer.