title: Electrophoretic analysis of the cleaved form of serpin, squamous cell carcinoma antigen-1 in normal and malignant squamous epithelial tissues.
abstract: The aim of this study was to detect the cleaved form of serine proteinase inhibitor (serpin), squamous cell carcinoma (SCC) antigen-1 in normal and malignant squamous epithelial tissues, which implies the presence of its target proteinase. The cleaved SCC antigen-1 in normal squamous epithelium was identified as a single spot with pI 6.35 and M(r) 40,000 by two-dimensional electrophoresis (2-DE) combined with immunoblotting. Interestingly, the cleaved form showed different biochemical properties in heat stability or immunoreactivity with a monoclonal antibody for SCC antigen (Mab 426) compared to intact SCC antigen-1. Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis of tissue extracts showed an abundant 40 kDa band of cleaved SCC antigen-1 in tumor tissue compared to normal tissue. Among the potential target proteinase of SCC antigen-1, immunoblotting analyses revealed that cathepsin L2 was remarkably overexpressed in tumor tissue, while cathepsin L was expressed in both normal and tumor tissues. These findings indicate that SCC antigen-1 interacts with specific endogenous proteinases such as cathepsins L and L2 in physiological and pathological states of squamous epithelium.
authors.affiliation: Department of Reproductive, Pediatric and Infectious Science, University School of Medicine, Ube, Japan. obgyn@po.cc.yamaguchi-u.ac.jp
authors.forename: Shugo
authors.initials: S
authors.lastname: Nawata
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Nakamura
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Hirakawa
authors.forename: Kotaro
authors.initials: K
authors.lastname: Sueoka
authors.forename: Tomoko
authors.initials: T
authors.lastname: Emoto
authors.forename: Akihiro
authors.initials: A
authors.lastname: Murakami
authors.forename: Kenji
authors.initials: K
authors.lastname: Umayahara
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Ogata
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Suminami
authors.forename: Fumitaka
authors.initials: F
authors.lastname: Numa
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kato
mesh_terms: D000951:Antigens, Neoplasm / Q000032:analysis / Q000302:isolation & purification*; D002403:Cathepsins / Q000032:analysis / Q000302:isolation & purification; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods*; D010450:Endopeptidases / Q000032:analysis / Q000302:isolation & purification; D006801:Humans; D015151:Immunoblotting; D018307:Neoplasms, Squamous Cell / Q000737:chemistry* / Q000473:pathology; D015843:Serpins / Q000032:analysis / Q000302:isolation & purification*
chemical_list: D000951:Antigens, Neoplasm; D015843:Serpins; C051072:squamous cell carcinoma-related antigen; D002403:Cathepsins; D010450:Endopeptidases