title: Isolation, purification, and characterization of a collagen-associated serpin, caspin, produced by murine colon adenocarcinoma cells.
abstract: A 45-kDa serpin secreted by a murine colon adenocarcinoma cell line, colon26, was isolated, purified, and characterized. It was found to bind specifically to type I collagen with high affinity and to type III collagen with lower affinity. Immunohistochemical studies of murine embryonic tissues showed a specific distribution of this collagen-associated serpin, named caspin, in relation to the formation of bone, cartilage, teeth, and basement membrane. The expression of caspin in high and low lung metastatic subclones of colon26 cell lines was inversely correlated with their metastatic capacity: low lung metastatic cells secreted higher amounts of caspin than their high lung metastatic counterparts. Caspin also demonstrated high homology with human pigment epithelium-derived factor/early population doubling level cDNA-1, which reportedly induces neuronal differentiation of human retinoblastoma cells and is expressed in association with G0 growth arrest. These findings suggest that caspin/pigment epithelium-derived factor/early population doubling level cDNA-1 is a novel factor that might play a crucial role in embryogenesis and tumor metastasis through binding to the extracellular matrix.
authors.affiliation: Pathophysiology Unit, Aichi Cancer Center Research Institute, Chikusa-ku, Nagoya, Aichi 464-8681, Japan. kkozaki@aichi-cc.pref.aichi.jp
authors.forename: K
authors.initials: K
authors.lastname: Kozaki
authors.forename: O
authors.initials: O
authors.lastname: Miyaishi
authors.forename: O
authors.initials: O
authors.lastname: Koiwai
authors.forename: Y
authors.initials: Y
authors.lastname: Yasui
authors.forename: A
authors.initials: A
authors.lastname: Kashiwai
authors.forename: Y
authors.initials: Y
authors.lastname: Nishikawa
authors.forename: S
authors.initials: S
authors.lastname: Shimizu
authors.forename: S
authors.initials: S
authors.lastname: Saga
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015374:Biosensing Techniques; D003094:Collagen / Q000378:metabolism*; D003110:Colonic Neoplasms / Q000201:enzymology*; D004622:Embryo, Mammalian / Q000166:cytology / Q000201:enzymology; D005109:Extracellular Matrix / Q000378:metabolism; D005136:Eye Proteins; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D007150:Immunohistochemistry; D051379:Mice; D008969:Molecular Sequence Data; D009362:Neoplasm Metastasis / Q000503:physiopathology; D009363:Neoplasm Proteins / Q000737:chemistry*; D009414:Nerve Growth Factors; D011485:Protein Binding / Q000502:physiology; D011506:Proteins / Q000235:genetics; D015843:Serpins / Q000737:chemistry* / Q000235:genetics; D014407:Tumor Cells, Cultured; D000099174:Pigment Epithelium-Derived Factor
chemical_list: D003094:Collagen; D005136:Eye Proteins; D009363:Neoplasm Proteins; D009414:Nerve Growth Factors; D011506:Proteins; D015843:Serpins; D000099174:Pigment Epithelium-Derived Factor; C112989:Caspin