Anti-SPARC/Osteonectin

SPARC (Secreted protein, acidic, cysteine-rich) is a glycoprotein that binds to collagen type I and other proteins in the extracellular matrix. It is involved in normal tissue remodeling as it regulates the deposition of extracellular matrix, and also plays a role in neoplastic transformation. It modulates interactions between tumoral cells and the peri-tumoral stroma. Homozygous mutations in SPARC give rise to severe bone fragility in humans. SPARC negatively regulates glucose metabolism in hepatocellular carcinoma (HCC). Overexpression of SPARC inhibited glucose uptake and lactate product through downregulation of key enzymes of glucose metabolism. Protein function: Appears to regulate cell growth through interactions with the extracellular matrix and cytokines. Binds calcium and copper, several types of collagen, albumin, thrombospondin, PDGF and cell membranes. There are two calcium binding sites, an acidic domain that binds 5 to 8 Ca(2+) with a low affinity and an EF-hand loop that binds a Ca(2+) ion with a high affinity. [The UniProt Consortium]