Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
2002-11-18
pubmed:abstractText
Restoration of expression of the retinoblastoma gene to DU-145 prostate-cancer cells sensitizes them to apoptosis induced by gamma-irradiation. In contrast, RB expression-protected cells from UV-induced cell death. RB, a caspase substrate, remained intact during apoptosis in gamma-irradiated DU-145 cells because serine proteases, but not caspases, were activated. In DU-145 cells, RB-mediated apoptosis involved biphasic activation of ABL kinase. ABL kinase was activated within minutes of irradiation, but in the presence of RB expression ABL kinase activation was enhanced 48 h after irradiation, coincident with the onset of cell death. Apoptosis was inhibited by RB mutants with constitutive ABL binding, but ABL overexpression overcame the effect of the RB mutant constructs. Expression of kinase-dead ABL had a dominant-negative effect on RB-mediated cell death. Activation of JUN N-terminal kinase depended on the presence of RB and occurred within 8 h of irradiation. Mutant JUN proteins that lacked the N-terminal transactivation domain and serine substrates for JUN N-terminal kinase inhibited cell death in a dominant-negative manner. Irradiation of DU-145 cells caused activation of p38 MAPK independent of the expression of RB. Inhibitors of p38 MAPK blocked apoptosis after irradiation of RB-expressing cells. The data show that after gamma-irradiation, intact RB mediates transcriptional activation that leads to activation of JNK and late activation of ABL kinase. In addition, p38 MAPK activation occurred independent of RB. ABL kinase, JUN N-terminal kinase, and p38 MAPK activity were all required for RB-mediated DU-145 cell death after gamma-irradiation.
pubmed:grant
pubmed:language
eng
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Caspases, http://linkedlifedata.com/resource/pubmed/chemical/Insulin-Like Growth Factor Binding..., http://linkedlifedata.com/resource/pubmed/chemical/Insulin-Like Growth Factor I, http://linkedlifedata.com/resource/pubmed/chemical/JNK Mitogen-Activated Protein..., http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Protein-Serine-Threonine Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-abl, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-akt, http://linkedlifedata.com/resource/pubmed/chemical/Recombinant Fusion Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Retinoblastoma Protein
pubmed:status
MEDLINE
pubmed:author
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
44969-79
pubmed:dateRevised
2009-11-19
pubmed:articleTitle
Retinoblastoma protein-mediated apoptosis after gamma-irradiation.
pubmed:affiliation
Department of Medicine, Lombardi Cancer Center, Georgetown University, Washington, DC 20007-2197, USA.