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Predicate | Object |
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rdf:type | |
lifeskim:mentions | |
pubmed:issue |
4
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pubmed:dateCreated |
1992-11-23
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pubmed:abstractText |
Expression of the cysteine proteinase cathepsin B and its physiological inhibitor cystatin C was analyzed in vitro in 1 human fibrosarcoma and 4 human colon carcinoma cell lines. Cystatin C antigen as well as cathepsin B activity were detected in the conditioned media of the 5 cell lines. The corresponding cell extracts expressed high levels of cathepsin B activity, whereas only trace amounts of cystatin C antigen could be found. Northern-blot analysis revealed the presence in the 5 cell lines of a 0.8-kb cystatin C mRNA transcript and 2 cathepsin B transcripts of 2.3 and 4.3 kb. Pepsin treatment of tumor-cell-released cathepsin B induced an average 7.3-fold increase in activity, indicating that the enzyme was mainly present as a latent form in conditioned medium. The pepsin-activated cathepsin B from one colon carcinoma cell line was further characterized using the cysteine proteinase inhibitors E-64, recombinant cystatin C, a cystatin-C-derived peptidyl inhibitor (Z-LVG-CHN2), and cathepsin-B-specific diazomethyl ketone inhibitors (Z-FT(OBzl)-CHN2, Z-FS(OBzl)-CHN2). This activity was totally neutralized by recombinant cystatin C, suggesting a potential for interaction between released extracellular cathepsin B and cystatin C. In vitro assays of degradation of extracellular matrix showed that cysteine proteinase inhibitors could decrease matrix degradation induced by pepsin-activated conditioned media. With colon cells, this inhibition was not observed, indicating a requirement for an extracellular activation of latent cathepsin B. Our data provide evidence that cystatin C and latent cathepsin B are both released extracellularly by colon carcinoma cells in vitro. They suggest that cystatin C and cathepsin B interactions may participate, in an as yet unelucidated way, in the modulation of the invasive phenotype of human colonic tumors.
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pubmed:language |
eng
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pubmed:journal | |
pubmed:citationSubset |
IM
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pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/CST3 protein, human,
http://linkedlifedata.com/resource/pubmed/chemical/Cathepsin B,
http://linkedlifedata.com/resource/pubmed/chemical/Culture Media, Conditioned,
http://linkedlifedata.com/resource/pubmed/chemical/Cystatin C,
http://linkedlifedata.com/resource/pubmed/chemical/Cystatins,
http://linkedlifedata.com/resource/pubmed/chemical/Cysteine Proteinase Inhibitors,
http://linkedlifedata.com/resource/pubmed/chemical/Protease Inhibitors
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pubmed:status |
MEDLINE
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pubmed:month |
Oct
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pubmed:issn |
0020-7136
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pubmed:author | |
pubmed:issnType |
Print
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pubmed:day |
21
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pubmed:volume |
52
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pubmed:owner |
NLM
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pubmed:authorsComplete |
Y
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pubmed:pagination |
645-52
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pubmed:dateRevised |
2008-11-21
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pubmed:meshHeading |
pubmed-meshheading:1399147-Carcinoma,
pubmed-meshheading:1399147-Cathepsin B,
pubmed-meshheading:1399147-Colonic Neoplasms,
pubmed-meshheading:1399147-Culture Media, Conditioned,
pubmed-meshheading:1399147-Cystatin C,
pubmed-meshheading:1399147-Cystatins,
pubmed-meshheading:1399147-Cysteine Proteinase Inhibitors,
pubmed-meshheading:1399147-Enzyme Activation,
pubmed-meshheading:1399147-Extracellular Matrix,
pubmed-meshheading:1399147-Fibrosarcoma,
pubmed-meshheading:1399147-Humans,
pubmed-meshheading:1399147-Protease Inhibitors,
pubmed-meshheading:1399147-Tumor Cells, Cultured
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pubmed:year |
1992
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pubmed:articleTitle |
Cystatin C and cathepsin B in human colon carcinoma: expression by cell lines and matrix degradation.
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pubmed:affiliation |
Swiss Institute for Experimental Cancer Research (ISREC), Epalinges.
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pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
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