Linked Life Data

14534528

Source:http://linkedlifedata.com/resource/pubmed/id/14534528

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
44
pubmed:dateCreated
2003-10-9
pubmed:abstractText
Most papillary thyroid carcinomas (PTC) have an isozyme-specific reduction of protein kinase C (PKC)epsilon, which occurs through a post-transcriptional mechanism. Here, we test whether the oncoprotein RET/PTC could be responsible for this effect, since RET/PTC rearrangements are quite prevalent in PTC and RET/PTC activates PLCgamma, an upstream modulator of PKCs. At 3 h after induction of RET/PTC1 or RET/PTC3 expression, there was evidence of PKCepsilon activation. Activation was restricted to PKCepsilon, as acute expression of RET/PTC did not change the subcellular distribution of other PKC isozymes expressed in PCCL3 cells. Prolonged RET/PTC expression (2-6 days) produced an isozyme-specific change in PKCepsilon subcellular localization and a decrease in total PKCepsilon levels. The expression of RET/PTC3(Y541F), which does not interact with PLCgamma, but signals normally through other RET effectors, had no effect on PKCepsilon distribution at any of the time points examined. However, downregulation of total PKCepsilon levels was only partially prevented by expression of RET/PTC(Y541F). Cells with decreased PKCepsilon following prolonged expression of RET/PTC were relatively resistant to doxorubicin-induced apoptosis. Based on our previous observation that PCCL3 cells expressing a dominant-negative PKCepsilon are also markedly resistant to apoptosis, we propose that selective downregulation of PKCepsilon following prolonged RET/PTC activation promotes cell survival and clonal expansion.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0950-9232
pubmed:author
pubmed:issnType
Print
pubmed:day
9
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6830-8
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Acute expression of RET/PTC induces isozyme-specific activation and subsequent downregulation of PKCepsilon in PCCL3 thyroid cells.
pubmed:affiliation
Division of Endocrinology and Metabolism, University of Cincinnati College of Medicine, Mail Location 0547, Cincinnati, OH 45267, USA. Jeffrey.Knauf@UC.EDU
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.