Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
1990-4-12
pubmed:abstractText
The degradation of subendothelial and smooth muscle matrices by normal and neoplastic uroepithelial cells grown under serum-free conditions was examined. Normal urothelial cells were compared with neoplastic cells derived from a low grade papillary tumor (RT4) and a more invasive carcinoma (EJ). Low levels of degradation were observed with all cell types in serum-free medium alone. Supplementing the medium with plasminogen increased the degradative activity of each cell type. Logarithmically growing normal urothelial cells degraded extracellular matrix proteins 6 to 14 times faster on a per cell basis than their transformed counterparts. Analysis of the residual matrix constituents revealed that, while the levels of glycoprotein breakdown by the normal and neoplastic cells were similar, the normal cells degraded more of the collagen components than the neoplastic cells. Epidermal growth factor and cell density were examined as possible regulators of degradative activity. The neoplastic cells were not responsive to cell density as a regulatory factor and were only slightly responsive to epidermal growth factor. However, epidermal growth factor increased the degradative activity of logarithmically growing normal urothelial cells in the presence of plasminogen and the activity of confluent cells was increased to an even greater extent. Gelatin substrate gel analysis confirmed that the normal urothelial cells elaborated a more diverse set of gelatinases than the tumorigenic cells. Although normal urothelial cells had higher degradative abilities than their malignant counterparts, it is significant that the neoplastic cells were less responsive to regulatory signals in our model system. Thus, loss of regulatory mechanisms for protease secretion and matrix degradation may be a more important determinant of invasive ability in vivo than protease secretion or matrix degradation in vitro.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
50
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1897-904
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Rapid degradation of extracellular matrix proteins by normal human uroepithelial cells.
pubmed:affiliation
Urologic Cancer Research Laboratory, Kenneth Norris Jr. Comprehensive Cancer Center, University of Southern California, Los Angeles 90033.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't