Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
11
pubmed:dateCreated
2008-11-12
pubmed:abstractText
A cytokine-dependent (FL5.12), drug-sensitive, p53 wild type (WT) and a doxorubicin-resistant derivative line (FL/Doxo) were used to determine the mechanisms that could result in drug resistance of early hematopoietic precursor cells. Drug resistance was associated with decreased p53 induction after doxorubicin treatment, which was due to a higher level of proteasomal degradation of p53. Dominant-negative (DN) p53 genes increased the resistance to chemotherapeutic drugs, MDM-2 and MEK inhibitors, further substantiating the role of p53 in therapeutic sensitivity. The involvement of signal transduction and apoptotic pathways was examined, as drug resistance did not appear to be due to increased drug efflux. Drug-resistant FL/Doxo cells had higher levels of activated Raf/MEK/ERK signaling and decreased induction of apoptosis when cultured in the presence of doxorubicin than drug-sensitive FL5.12 cells. Introduction of DN MEK1 increased drug sensitivity, whereas constitutively active (CA) MEK1 or conditionally active BRAF augmented resistance, documenting the importance of the Raf/MEK/ERK pathway in drug resistance. MEK inhibitors synergized with chemotherapeutic drugs to reduce the IC(50). Thus the p53 and Raf/MEK/ERK pathways play key roles in drug sensitivity. Targeting these pathways may be effective in certain drug-resistant leukemias that are WT at p53.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Annexin A5, http://linkedlifedata.com/resource/pubmed/chemical/Caspases, http://linkedlifedata.com/resource/pubmed/chemical/Cysteine Proteinase Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Doxorubicin, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/Extracellular Signal-Regulated MAP..., http://linkedlifedata.com/resource/pubmed/chemical/Imidazoles, http://linkedlifedata.com/resource/pubmed/chemical/Leupeptins, http://linkedlifedata.com/resource/pubmed/chemical/Mdm2 protein, mouse, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinase..., http://linkedlifedata.com/resource/pubmed/chemical/Piperazines, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-mdm2, http://linkedlifedata.com/resource/pubmed/chemical/Tumor Suppressor Protein p53, http://linkedlifedata.com/resource/pubmed/chemical/benzyloxycarbonylleucyl-leucyl-leuci..., http://linkedlifedata.com/resource/pubmed/chemical/nutlin 3, http://linkedlifedata.com/resource/pubmed/chemical/raf Kinases
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1476-5551
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
22
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2080-90
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:18685611-Animals, pubmed-meshheading:18685611-Annexin A5, pubmed-meshheading:18685611-Apoptosis, pubmed-meshheading:18685611-Blotting, Western, pubmed-meshheading:18685611-Caspases, pubmed-meshheading:18685611-Cells, Cultured, pubmed-meshheading:18685611-Cysteine Proteinase Inhibitors, pubmed-meshheading:18685611-Doxorubicin, pubmed-meshheading:18685611-Drug Resistance, pubmed-meshheading:18685611-Enzyme Activation, pubmed-meshheading:18685611-Enzyme Inhibitors, pubmed-meshheading:18685611-Extracellular Signal-Regulated MAP Kinases, pubmed-meshheading:18685611-Genes, Dominant, pubmed-meshheading:18685611-Hematopoietic Stem Cells, pubmed-meshheading:18685611-Imidazoles, pubmed-meshheading:18685611-Leupeptins, pubmed-meshheading:18685611-Mice, pubmed-meshheading:18685611-Mitogen-Activated Protein Kinase Kinases, pubmed-meshheading:18685611-Phosphorylation, pubmed-meshheading:18685611-Piperazines, pubmed-meshheading:18685611-Proto-Oncogene Proteins c-mdm2, pubmed-meshheading:18685611-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:18685611-Signal Transduction, pubmed-meshheading:18685611-Tumor Suppressor Protein p53, pubmed-meshheading:18685611-raf Kinases
pubmed:year
2008
pubmed:articleTitle
Involvement of p53 and Raf/MEK/ERK pathways in hematopoietic drug resistance.
pubmed:affiliation
Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, NC 27858, USA. mccubreyj@ecu.edu
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural