JAG1 and neoplasm: Key proteins, including jagged-1 (JAG1), Annexin II, Dll4, Tetraspanin Tspan8, latent TGF-β, and bioactive molecules like EDIL-3, enhance endothelial cell proliferation, migration, and vascular development through signaling pathways such as HIF-1α/Notch1, Src/FAK, and EGFR, contributing to tumor progression and tissue repair.