αvβ3

Integrin αvβ3 is a heterodimeric receptor that mediates cell adhesion to extracellular matrix (ECM) proteins, primarily vitronectin, and regulates angiogenesis and tumor cell survival^[1][2]. Mechanistically, αvβ3 interacts with intracellular signaling pathways including FAK/ERK to promote osteogenesis and endothelial migration, making it a pivotal regulator of tissue remodeling and pathological angiogenesis^[3]. In disease models, αvβ3 expression is elevated in neuroendocrine prostate cancer, medulloblastoma, glioblastoma, and ovarian carcinoma, correlating with tumor aggressiveness, metastatic potential, and radioresistance^[4][5][6][7]. Compared with related αv integrins such as αvβ5 and αvβ6, αvβ3 exhibits higher expression in tumor-associated vasculature and metastatic tumor cells, and it mediates platelet-assisted extravasation during hematogenous metastasis^[8][2]. In experimental applications, selective αvβ3 inhibitors and agonists, including cyclic RGD peptides and fluorescent or radiolabeled RGD-based ligands, have been used to modulate angiogenesis, visualize tumors via PET/SPECT imaging, and inhibit ectopic ossification or tumor progression in preclinical models^[3][6][7][9]. The combination of αvβ3-targeted imaging and pharmacologic blockade provides a dual platform for both mechanistic studies and potential therapeutic intervention in oncology and vascular disease research^[6][9].