Integrin alpha-V beta-3, Integrin alpha-V beta-5, and Integrin alpha-V beta-6 (αvβ3, αvβ5, αvβ6)

Integrins αvβ3, αvβ5, and αvβ6 are members of the integrin family of heterodimeric transmembrane receptors that mediate cell-extracellular matrix (ECM) and cell-cell interactions [Wikipedia, NIH]. These specific integrins share the alpha-V (αv) subunit and primarily recognize the Arginine-Glycine-Aspartic acid (RGD) motif in ligands such as vitronectin, fibronectin, and osteopontin [NIH]. They play critical roles in biological processes including angiogenesis, cell migration, and the mechanical activation of latent TGF-beta, a function particularly prominent for αvβ6 [NIH, ResearchGate]. In disease states, these integrins are frequently upregulated; αvβ3 and αvβ5 are key drivers of tumor-associated angiogenesis and metastasis, while αvβ6 is a major mediator of tissue fibrosis and epithelial-mesenchymal transition in carcinomas [NIH, MDPI]. Therapeutic strategies targeting these receptors include monoclonal antibodies and small molecule inhibitors designed to block ligand binding and inhibit downstream signaling pathways like FAK and Src [NIH, ClinicalTrials.gov]. Although some candidates like cilengitide faced challenges in late-stage clinical trials, these integrins remain high-interest targets for both oncology and fibrotic diseases, as well as for molecular imaging applications [MDPI, ACS Publications].

Other names

Alpha-V integrinsVitronectin receptorsRGD-binding integrinsCD51/CD61 (αvβ3)CD51/ITGB5 (αvβ5)ITGAV/ITGB6 (αvβ6)

These integrins function by binding to the RGD (Arg-Gly-Asp) motif of extracellular matrix proteins, which triggers intracellular signaling pathways such as FAK/Src and PI3K/Akt to promote cell survival and migration [Wikipedia, NIH]. Drugs targeting these receptors typically act as competitive antagonists that block ligand binding, thereby inhibiting angiogenesis, tumor growth, and the activation of latent TGF-beta [NIH, MDPI].