Linked Life Data

2790786

Source:http://linkedlifedata.com/resource/pubmed/id/2790786

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
20
pubmed:dateCreated
1989-11-15
pubmed:abstractText
A number of epidermal growth factor (EGF)-resistant clones have been isolated from human epidermoid carcinoma A431 cells (I. King and A. C. Sartorelli, Biochem. Biophys. Res. Commun., 140: 837, 1986). These cells had a higher capacity to enter a pathway of terminal differentiation, as determined by their ability to form cornified envelopes. Thus, after 6 days in culture, 10% of parental A431 cells expressed a differentiated phenotype, while more than 50% of each of the EGF-resistant variants (M1, A5, and A7) formed cornified envelopes. These EGF-resistant clones expressed fewer EGF receptors and had a lower capacity for EGF receptor autophosphorylation than parental A431 cells. Clone M1 had the highest capacity to form cornified cell envelopes and expressed about 10% of the EGF receptor autophosphorylation activity of parental cells. The decrease in the level of EGF receptor autophosphorylation appeared to be due to a decrease in EGF receptor number rather than to a lowering of enzyme activity per se. Southern analysis demonstrated that all of the EGF-resistant variants contained fewer copies of the EGF receptor gene and no apparent gene rearrangement was detected in these variant cells. A corresponding decrease in EGF receptor mRNA was also observed in M1, A5, and A7 cells, with a ratio of 18:1:10:5 for A431, M1, A5, and A7 cells, respectively. In addition, two other malignant epithelial cell lines, SqCC/Y1 and FaDu, contained relatively few copies of EGF receptor genes, had low EGF receptor kinase activity and showed a relatively high capacity to form cornified envelopes. These findings suggest that the level of the EGF receptor was critical to the regulation of the degree of maturation of malignant epidermal cells.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
49
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
5677-81
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
1989
pubmed:articleTitle
Epidermal growth factor receptor gene expression, protein kinase activity, and terminal differentiation of human malignant epidermal cells.
pubmed:affiliation
Department of Pharmacology, Yale University School of Medicine, New Haven, Connecticut 06510.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.