VDR and neoplasm: In addition to acting on VEGF/VEGFR affecting ECs in the treatment of tumors, peroxisome proliferator-activated receptors (PPARs) and vitamin D receptors (VDR) are also targets for the treatment of tumors targeting ECs, such as PPARα ligands have a powerful effect in inhibiting endothelial cell proliferation and angiogenesis, and the PPARα agonist fenofibrate can inhibit endothelial cell proliferation and VEGF production thereby inhibiting tumor growth [266].