Switch to
Predicate | Object |
---|---|
rdf:type | |
lifeskim:mentions | |
pubmed:issue |
1
|
pubmed:dateCreated |
1998-4-15
|
pubmed:abstractText |
We have investigated the effects of laminin, on the plasminogen-activator system of MCF-7 breast-carcinoma cells. MCF-7 cells were incubated on plastic or laminin-coated wells, and medium and cell lysate aliquots were assayed for tissue-type (tPA) and urokinase-type plasminogen activator (uPA) by a chromogenic assay in combination with anti-uPA antibodies. Cells cultured on laminin displayed a 5-fold increase in tPA activity and a 2-fold decrease in uPA activity relative to cells on plastic. These effects could be mimicked by laminin fragment P1 but not by collagen I or fibronectin. tPA activity of cells treated with estradiol (10 nM) was 3-fold higher, that of cells on laminin treated with estradiol was 15-fold higher, than that of control. Northern-blot analysis showed that tPA mRNA levels were up-regulated by estradiol and laminin, whereas PAI-1 mRNA levels were down-regulated by laminin and not affected by E2. Concomitant treatment with laminin and estradiol, decreased PAI-1 mRNA and increased tPA mRNA levels, accounting for the synergistic increase in tPA activity. Laminin exerted only a modest (approx. 2-fold) inhibitory effect on uPA mRNA levels. In the breast-carcinoma cell line MDA-MB-231, down-regulation of PAI-1 and uPA mRNA by laminin was not observed. Adhesion assays indicated that alpha2beta1 is the predominant receptor for laminin in MCF-7 cells. MDA-MB-231 cells expressed alpha2 (54%) but this integrin is not used as a laminin receptor. These results support a role for alpha2beta1 in mediating interactions of MCF-7 with LN.
|
pubmed:language |
eng
|
pubmed:journal | |
pubmed:citationSubset |
IM
|
pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Estradiol,
http://linkedlifedata.com/resource/pubmed/chemical/Integrins,
http://linkedlifedata.com/resource/pubmed/chemical/Laminin,
http://linkedlifedata.com/resource/pubmed/chemical/RNA, Messenger,
http://linkedlifedata.com/resource/pubmed/chemical/Tissue Plasminogen Activator,
http://linkedlifedata.com/resource/pubmed/chemical/Urokinase-Type Plasminogen Activator
|
pubmed:status |
MEDLINE
|
pubmed:month |
Mar
|
pubmed:issn |
0020-7136
|
pubmed:author | |
pubmed:issnType |
Print
|
pubmed:day |
30
|
pubmed:volume |
76
|
pubmed:owner |
NLM
|
pubmed:authorsComplete |
Y
|
pubmed:pagination |
77-85
|
pubmed:dateRevised |
2008-11-21
|
pubmed:meshHeading |
pubmed-meshheading:9533765-Breast Neoplasms,
pubmed-meshheading:9533765-Cell Adhesion,
pubmed-meshheading:9533765-Drug Synergism,
pubmed-meshheading:9533765-Estradiol,
pubmed-meshheading:9533765-Humans,
pubmed-meshheading:9533765-Integrins,
pubmed-meshheading:9533765-Laminin,
pubmed-meshheading:9533765-RNA, Messenger,
pubmed-meshheading:9533765-Tissue Plasminogen Activator,
pubmed-meshheading:9533765-Tumor Cells, Cultured,
pubmed-meshheading:9533765-Up-Regulation,
pubmed-meshheading:9533765-Urokinase-Type Plasminogen Activator
|
pubmed:year |
1998
|
pubmed:articleTitle |
Laminin and estradiol regulation of the plasminogen-activator system in MCF-7 breast-carcinoma cells.
|
pubmed:affiliation |
Departamento de Radiologia de Faculdade de Medicina da USP, São Paulo, Brazil.
|
pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|