Sulfated cell-surface proteoglycan (HSPG)

Sulfated cell-surface proteoglycans, most notably heparan sulfate proteoglycans (HSPGs) such as syndecans and glypicans, are complex glycoproteins characterized by a core protein attached to sulfated glycosaminoglycan (GAG) chains. These molecules are ubiquitous on the plasma membrane of animal cells, where they serve as critical regulators of the cellular microenvironment by binding a vast array of ligands, including growth factors, cytokines, and extracellular matrix proteins (Sarrazin et al., 2011, Cold Spring Harb Perspect Biol). By acting as co-receptors, they facilitate the formation of signaling complexes, thereby modulating pathways involved in cell proliferation, migration, and differentiation. In the context of infectious disease, many viruses and bacteria utilize these sulfated chains as initial attachment factors to concentrate on the cell surface before engaging specific entry receptors (Clausen et al., 2020, Cell). In oncology, dysregulation of these proteoglycans or their modifying enzymes, such as heparanase, promotes tumor angiogenesis and metastasis by releasing sequestered growth factors (Knelson et al., 2014, Nat Rev Cancer). Consequently, they are targeted by heparin mimetics and small molecules designed to disrupt these interactions or inhibit their degradation, offering therapeutic potential in cancer and viral infections (Hammond et al., 2014, Glycobiology).

Other names

Heparan sulfate proteoglycanCell-surface HSPGSyndecanGlypicanChondroitin sulfate proteoglycanCell-surface GAG

Competitive inhibition of ligand binding to glycosaminoglycan chains and inhibition of heparanase-mediated degradation of the extracellular matrix.