Linked Life Data

3036888

Source:http://linkedlifedata.com/resource/pubmed/id/3036888

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1987-8-5
pubmed:abstractText
Cyclic AMP functions as a negative regulator of cell proliferation in a variety of cell systems. We show here that the proliferation of normal and neoplastic B cells can be inhibited by high intracellular levels of cAMP. Thus forskolin treatment of the neoplastic B precursor cell line Reh induced a rapid increase in the cAMP level, which was followed by an accumulation of cells in the G0/G1 phase of the cell cycle over a period of 2-3 days. Similar inhibition of Reh cell proliferation after 3 days was observed whether forskolin was present continuously or only during the first 5 hr. Both c-myc and c-Ha-ras protein levels were transiently down-regulated at 4 hr of forskolin treatment, suggesting that these protooncogenes play a role in the process leading to cAMP-mediated growth cessation. Northern-blot analysis showed that the steady-state levels of c-myc RNA rapidly declined in all phases of the cell cycle, to return to control levels within a time period of 24 hr. In contrast, the c-Ha-ras mRNA level was steadily maintained. Thus the expression of c-myc and c-Ha-ras protein was regulated at different metabolic levels. The reduced proliferative capacity of the B precursor cell line in the presence of forskolin was not linked to induced differentiation. This was judged from the lack of appearance of three different B cell differentiation markers; cytoplasmic immunoglobulin heavy chain and two antigens recognized by the monoclonal antibodies B1 (CD20) and HH1 (CD37). We also showed that forskolin partially inhibited the proliferation of normal B lymphocytes stimulated by anti-immunoglobulins (anti-mu) and B cell growth factor (BCGF). The burst of c-myc mRNA during activation of normal B cells was also reduced by forskolin.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0021-9541
pubmed:author
pubmed:issnType
Print
pubmed:volume
131
pubmed:owner
NLM
pubmed:authorsComplete
N
pubmed:pagination
426-33
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Cyclic AMP-mediated suppression of normal and neoplastic B cell proliferation is associated with regulation of myc and Ha-ras protooncogenes.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't