Linked Life Data

7819134

Source:http://linkedlifedata.com/resource/pubmed/id/7819134

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1995-2-14
pubmed:abstractText
We have investigated the expression of protein kinase C (PKC) and protein kinase A (PKA) during the phases of growth and differentiation of the human colon carcinoma Caco-2 cells. We studied whether differentiation correlated with the responsiveness to cAMP and with an increased transport of the catalytic subunit of PKA into the nucleus. Also, we evaluated whether this phenomenon was affected by PKC activity. High levels of activated PKC were found in the plasma membranes of replicating cells. When the cells began to differentiate, plasma membrane-activated PKC decreased, while the cytosolic fraction increased. On the contrary, PKA holoenzyme increased during differentiation, along with the transport of its catalytic subunit into the nucleus. Both types I and II kinase A holoenzymes increased during differentiation, with maximal type II activity found when cells were fully differentiated. In replicating preconfluent cells, the inhibition of PKC by high dose phorbol 12-myristate 13-acetate or sphingosine increased the amount of both PKA catalytic subunit in the nucleus and sucrase activity. During differentiation, 8-Bromo-cAMP increased PKA catalytic subunit in the nucleus and apoliprotein A1 mRNA levels. These effects were inhibited by low-dose phorbol 12-myristate 13-acetate, which activates PKC in the plasma membranes. Our data suggest that PKC is activated in proliferating Caco-2 cells. The inhibition of PKC induces the transport of PKA catalytic subunit into the nucleus and the expression of the differentiation markers. Differentiated Caco-2 cells show a lower activation of PKC and an increased transport of the catalytic subunit of PKA into the nucleus.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
1044-9523
pubmed:author
pubmed:issnType
Print
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
967-73
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
The enterocyte-like differentiation of the Caco-2 tumor cell line strongly correlates with responsiveness to cAMP and activation of kinase A pathway.
pubmed:affiliation
Cattedra di Gastroenterologia, Facolta di Medicina e Chirurgia, Universita di Napoli Federico Il, Naples, Italy.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, Non-U.S. Gov't