Reverse-zymographic analysis of protease nexin-II/amyloid beta protein precursor of human carcinoma cell lines, with special reference to the grade of differentiation and metastatic phenotype

• Published in: International journal of cancer Vol. 60; no. 1; p. 123
• Main Authors: Kataoka, H, Seguchi, K, Iwamura, T, Moriyama, T, Nabeshima, K, Koono, M
• Format: Journal Article
• Language: English
• Published: United States 03-01-1995
• Subjects: Adenocarcinoma - enzymology; Adenocarcinoma - pathology; Adenocarcinoma - secondary; Amyloid beta-Protein Precursor - analysis; Base Sequence; Carcinoma, Squamous Cell - enzymology; Carcinoma, Squamous Cell - pathology; Carcinoma, Squamous Cell - secondary; Carcinoma, Transitional Cell - enzymology; Carcinoma, Transitional Cell - pathology; Carcinoma, Transitional Cell - secondary; Cell Differentiation; Culture Media, Serum-Free; Humans; Molecular Sequence Data; Neoplasm Metastasis - genetics; Neoplasms - enzymology; Neoplasms - pathology; Pancreatic Neoplasms - enzymology; Pancreatic Neoplasms - pathology; Phenotype; Serine Proteinase Inhibitors - analysis; Trypsin Inhibitors - analysis; Tumor Cells, Cultured
• ISSN: 0020-7136
• DOI: 10.1002/ijc.2910600118

Trypsin inhibitors in serum-free conditioned media (SFCM) of various human carcinoma cell lines were analyzed by reverse zymography. Most of the cells secreted high-molecular-weight trypsin inhibitors (HMTI) larger than 100 kDa. The cell lines of colorectal carcinoma origin had a tendency to secrete HMTI whose molecular weight was a little higher than that of the other cell lines. Analysis of SFCM of subclones with different histological differentiation and metastatic/invasive potentials derived from a single pancreatic carcinoma cell line SUIT-2 showed that the HMTI activity in SFCM was correlated to the degree of histological differentiation in vivo and tended to be inversely correlated to their metastatic/invasive capabilities. Immunoblotting analysis revealed that these HMTI were protease nexin-II/amyloid beta protein precursors (PN-II/APP). Semi-quantificative reverse-transcriptase/polymerase-chain reaction study for PN-II/APP mRNAs suggested that the differences in PN-II/APP activities in SFCM between the subclones might be post-transcriptional or post-secretional events. In addition, SFCM of a highly metastatic subclone contained 43-kDa protein which reacted to anti-APP monoclonal antibody (MAb) suggesting that the subclone may have APP-degrading activity.