Ephrin type-B receptor 4-ephrin-B2 complex (EphB4-EFNB2)

The EphB4-ephrin-B2 complex is a critical signaling unit composed of the Ephrin type-B receptor 4 (EphB4) and its cognate transmembrane ligand, ephrin-B2 (UniProt P54760, P52799). This interaction is unique for its bidirectional signaling capabilities, where 'forward' signaling occurs in the receptor-bearing cell and 'reverse' signaling occurs in the ligand-bearing cell, regulating processes such as cell adhesion, migration, and boundary formation (PubMed: 16707066). In normal physiology, this complex is essential for embryonic vascular development, specifically in the differentiation of arteries and veins. In the context of oncology, EphB4 is frequently overexpressed in various solid tumors, where its interaction with ephrin-B2 promotes tumor angiogenesis, growth, and metastasis (PubMed: 21460106). Therapeutic targeting of this complex involves the use of soluble decoy receptors like sEphB4-HSA to sequester the ligand or small molecule inhibitors to block the receptor's kinase activity, aiming to disrupt pathological vessel formation and tumor progression (ClinicalTrials.gov NCT01647828). Because of its role in vascular homeostasis, pharmacological modulation of this complex requires careful monitoring for side effects such as hypertension and impaired wound healing.

Other names

EphB4-ephrin-B2HTK-LERK5 complexEphB4-EFNB2 complexEph receptor B4-ephrin-B2 interaction

Competitive inhibition of ligand-receptor binding using soluble decoy receptors or small molecule inhibition of the EphB4 kinase domain to block downstream signaling pathways.