Biotinylated Recombinant Human Mesothelin (carrier-free) from BIOLEGEND

Mesothelin (MSLN) was initially cloned from a library of human pancreatic cancer cells. It was also identified by a monoclonal antibody, MAb K1, which recognized a glycoprotein present on the surface of mesothelial cells. The human MSLN gene encodes a about 71 kD precursor protein of 622 amino acids. The C-terminal glycosylphosphatidylinositol (GPI) anchor addition signal is removed (cleavage site: Ser598) and the latter replaced with a GPI anchor. The MSLN precursor is cleaved by furin at Arg295 into two products, a about 31 kD mature megakaryocyte potentiating factor (MPF residues Ser34 - Arg286) and a about 40 kD GPI-anchored membrane-bound mature mesothelin starting from Glu296. The 40 kD GPI-anchored mesothelin can be released by treatment with phosphatidylinositol-specific phospholipase C. Soluble mesothelin specifically binds to ovarian carcinoma cell line OVCAR-3, mediated by the cancer antigen 125 (CA125), a mucin-like glycoprotein on the surface of tumor cells. CA125 and mesothelin are co-expressed in advanced grade ovarian adenocarcinoma, and it has been speculated that CA125 might contribute to the metastasis of ovarian cancer to the peritoneum by initiating cell attachment to the mesothelial epithelium via binding to mesothelin. In addition, mesothelin and CA125/mucin 16 (CA125/MUC16) are co-overexpressed at the invading edges of pancreatic cancer tissues, and their expression correlates with poor survival rates. Mesothelin is highly expressed in several human cancers including malignant mesothelioma, pancreatic, ovarian, cholangiocarcinoma, and lung adenocarcinoma.