Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2007-6-20
pubmed:abstractText
Previous studies on apoptosis defects in acute lymphoblastic leukemia (ALL) have focused on chemotherapy-induced, primarily mitochondrial death pathways. Yet, immunologic surveillance mechanisms including sensitization to apoptotic signals mediated via the death receptor CD95 might contribute to leukemic control. Here, we show that primary B-cell precursor ALL cells from children escape from receptor-dependent cell death in 2 ways: Resting ALL blasts are protected from receptor-mediated apoptosis due to the absence of CD95 surface expression. However, even though CD40 ligation results in up-regulation of CD95, ALL blasts, unlike normal B cells, remain resistant to apoptosis. We show that this apoptosis resistance involves the selective up-regulation of the short isoforms of the caspase-8 inhibitor c-FLIP acting directly at the CD95 receptor level. Treatment with cycloheximide during CD40 activation prevents up-regulation of those c-FLIP isoforms and sensitizes ALL cells toward CD95-mediated apoptosis. We therefore propose that induction of the short c-FLIP isoforms inhibits the onset of CD95-induced apoptosis in primary CD40-stimulated ALL cells despite high CD95 expression.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-4971
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
110
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
384-7
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2007
pubmed:articleTitle
Up-regulation of c-FLIPS+R upon CD40 stimulation is associated with inhibition of CD95-induced apoptosis in primary precursor B-ALL.
pubmed:affiliation
Clinic for Pediatric Hematology, Heinrich Heine University of Duesseldorf, Germany. troeger@med.uni-duesseldorf.de
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't