Electrophoretic characterization of heat-stable squamous cell carcinoma antigen.
The aim of this study was to investigate the heat stability of squamous cell carcinoma (SCC) antigen, a tumor-associated serine proteinase inhibitor (serpin), in tumor tissue extract by electrophoretic methods. After heat treatment at 70 degrees C for 2 h, the tumor tissue extract showed a single main protein band of 45 kDa on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) which reacted with a monoclonal antibody specific for SCC antigen. The heat-stable SCC antigen was separated by two-dimensional electrophoresis (2-DE) into four spots with pI 6.4-5.9 and Mr 44500-45 000 of SCC antigen-1. Furthermore, the SCC antigen-1 still showed its inhibitory activity against a cysteine proteinase, papain, by gelatin zymography. These results suggest that heat treatment of protein sample at 70 degrees C for 2 h may be a useful method for a partial purification of SCC antigen-1 which can inhibit lysosomal cysteine proteinases such as cathepsin L, S, and K.
Nawata
S
S
Department of Obstetrics and Gynecology, Yamaguchi University School of Medicine, Ube, Japan. obgyn@po.cc.yamaguchi-u.ac.jp
Suminami
Y
Y
Hirakawa
H
H
Murakami
A
A
Umayahara
K
K
Ogata
H
H
Numa
F
F
Nakamura
K
K
Kato
H
H
D000951:Antigens, Neoplasm / Q000032:analysis*; D014408:Biomarkers, Tumor / Q000032:analysis*; D002294:Carcinoma, Squamous Cell / Q000737:chemistry* / Q000473:pathology; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D006361:Heating; D006801:Humans; D015843:Serpins / Q000032:analysis*; D012967:Sodium Dodecyl Sulfate; D014020:Tissue Extracts / Q000737:chemistry
D000951:Antigens, Neoplasm; D014408:Biomarkers, Tumor; D015843:Serpins; D014020:Tissue Extracts; C051072:squamous cell carcinoma-related antigen; D012967:Sodium Dodecyl Sulfate