Linked Life Data

9354681

Source:http://linkedlifedata.com/resource/pubmed/id/9354681

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1997-12-8
pubmed:abstractText
Homozygous p16(INK4A) (p16) gene deletion is frequent in primary tumor cells from acute lymphoblastic leukemia (ALL), suggesting that loss of p16 may be an important precursor to transformation in ALL. We have previously described JKB, a human ALL cell line, that contains homozygous deletion of the p16 gene. Because ectopic expression of p16 suppresses cell growth, we created a temperature sensitive p16 mutant to develop a system for inducible p16 function in human ALL. JKB cells were transfected either with a p16 gene mutated at position 119 (E119G) to confer temperature sensitivity (JKB p16MT) or with control vector. The percentage of cells in G1 phase was similar in JKB control cells or in JKB p16MT cells cultured at restrictive conditions (40 degrees C). However, with lowering of temperature from 40 degrees C to permissive conditions (31 degrees C), the percentage of JKB p16MT cells in G1 phase and binding of p16 to CDK4 and CDK6 increased, with associated decreases in CDK4 and CDK6 kinase activities, and dephosphorylation of retinoblastoma protein (pRB). Culture of JKB p16MT cells at 31 degrees C for >/=3 days irreversibly inhibited growth. Moreover, JKB p16MT cells cultured under these permissive conditions showed a less transformed morphology and more differentiated phenotype than did these cells cultured under restrictive temperatures. Finally, dexamethasone (Dex) induced apoptosis of JKB p16MT cells cultured at 40 degrees C, but did not trigger death of these cells cultured at 31 degrees C. These results suggest that deletion of p16 gene in JKB human ALL cells is associated with dysregulated growth of less differentiated tumor cells, which nonetheless remain susceptible to apoptosis triggered by Dex.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
90
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
4106-15
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
p16INK4A promotes differentiation and inhibits apoptosis of JKB acute lymphoblastic leukemia cells.
pubmed:affiliation
Division of Hematologic Malignancies, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't