Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-12-4
pubmed:abstractText
Elevated activities of cysteine proteinases such as cathepsins B and L and cancer procoagulant have been linked to tumor malignancy. In the present study we examined the hypothesis that these elevated activities could be due to impaired regulation by the endogenous low molecular mass cysteine proteinase inhibitors (cystatins). Inhibitors from human sarcoma were compared to those from human liver, a normal tissue in which the inhibitors had been characterized previously. An extract of cystatins from sarcoma was less effective against papain and cathepsin B (liver or tumor) than was an extract from liver. This reduced inhibitory capacity in sarcoma was not due to a reduction in either the concentrations or specific activities of the cystatins or an absence of any family or isoform of cystatins. We purified two members of the cystatin superfamily (stefin A and stefin B) to homogeneity and determined their individual inhibitory properties. Stefins B from liver and sarcoma exhibited comparable inhibition of papain and cathepsin B. In contrast, stefin A from sarcoma exhibited a reduced ability to inhibit papain, human liver cathepsins B, H and L and human and murine tumor cathepsin B. The Ki for inhibition of liver cathepsin B by sarcoma stefin A was 10-fold higher than that for inhibition of liver cathepsin B by liver stefin A, reflecting a reduction in the rate constant for association and an increase in the rate constant for dissociation. Cancer is now the third pathologic condition reported to be associated with alterations in cystatins, the other two being amyloidosis and muscular dystrophy.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
993
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
63-73
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Inhibitory properties of low molecular mass cysteine proteinase inhibitors from human sarcoma.
pubmed:affiliation
Department of Pharmacology, Wayne State University School of Medicine, Detroit, MI 48201.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't