Integrin alpha-5 (ITGA5) (ITGA5)

Integrin alpha-5 (ITGA5) is a transmembrane glycoprotein that functions as the alpha subunit of the heterodimeric integrin alpha-5 beta-1 (α5β1) receptor, also known as the fibronectin receptor [1, 4]. It plays a critical role in mediating cell-extracellular matrix (ECM) interactions by binding to the arginine-glycine-aspartic acid (RGD) motif found in ligands such as fibronectin and fibrinogen [1, 2]. This binding triggers 'outside-in' signaling pathways, including the activation of focal adhesion kinase (FAK) and Src, which regulate essential cellular processes like adhesion, migration, proliferation, and survival [3, 6]. In pathological conditions, ITGA5 is frequently overexpressed in the tumor microenvironment, particularly on tumor cells and angiogenic neovessels, where it promotes tumor progression, metastasis, and resistance to therapy [3, 11, 17]. Consequently, ITGA5 has emerged as a significant therapeutic target in oncology, with various antagonists, including monoclonal antibodies like volociximab and small peptides like ATN-161, developed to disrupt its pro-tumorigenic and pro-angiogenic functions [3, 11].

Other names

CD49eCD49 antigen-like family member EFibronectin receptor subunit alphaIntegrin alpha-FVLA-5FNRAITGA5

Antagonism of the alpha-5 beta-1 integrin complex, preventing ligand binding to the RGD motif and inhibiting downstream pro-survival and pro-migratory signaling pathways such as FAK/Src and PI3K/Akt [3, 6, 11].