Linked Life Data

15158089

Source:http://linkedlifedata.com/resource/pubmed/id/15158089

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2004-5-25
pubmed:abstractText
Acute myeloid leukemia (AML) is associated with dysregulated hematopoietic cell proliferation and increased bone marrow angiogenesis, each regulated by signaling through receptor tyrosine kinases (RTKs). SU5416 is a small molecule inhibitor of VEGF receptors, c-kit and FLT3 and therefore provides a novel opportunity to target both angiogenesis and proliferation in AML. SU5416 was assessed in a phase II hematological malignancy trial in the US, where partial responses were observed in two of 33 patients. Since AML provides a unique platform to evaluate mechanism of action of small molecule inhibitors, investigation of the effect of SU5416 on FLT3 expression and phosphorylation in blood and bone marrow was an additional focus of this trial. Phosphorylated FLT3 was detected by immunoprecipitation/Western analysis in peripheral blood samples from 17 of 22 patients, and seven exhibited strong inhibition of phosphorylation immediately following a 1h SU5416 infusion, demonstrating that SU5416 can modulate RTK phosphorylation in humans. Although no clear correlation with clinical response was observed, analysis of patient plasma drug levels suggested that a threshold SU5416 concentration of 15 microM was associated with FLT3 inhibition. This observation was supported by data from an ex vivo model where AML cells were spiked into human blood, established to mimic the clinical setting and enable more rigorous analysis of effect of SU5416. In addition, FLT3 protein levels were downregulated in patient bone marrow samples, analyzed by an RIA assay. To identify putative predictors of response, patient plasma was analyzed for levels of secreted ligands of SU5416 targets; SCF and FLT3 ligand. Baseline levels of SCF in patients with stable or progressive disease were significantly higher than those in normal donors, whereas FLT3 ligand levels in patients who exhibited progressive disease were significantly lower than those in normal donors. The translational and clinical analyses described in this report provide some insights into the mechanism and duration of action of SU5416.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0145-2126
pubmed:author
pubmed:issnType
Print
pubmed:volume
28
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
679-89
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:15158089-Acute Disease, pubmed-meshheading:15158089-Adult, pubmed-meshheading:15158089-Aged, pubmed-meshheading:15158089-Bone Marrow, pubmed-meshheading:15158089-Down-Regulation, pubmed-meshheading:15158089-Female, pubmed-meshheading:15158089-Humans, pubmed-meshheading:15158089-Indoles, pubmed-meshheading:15158089-Leukemia, Myeloid, pubmed-meshheading:15158089-Male, pubmed-meshheading:15158089-Membrane Proteins, pubmed-meshheading:15158089-Middle Aged, pubmed-meshheading:15158089-Mutation, pubmed-meshheading:15158089-Phosphorylation, pubmed-meshheading:15158089-Protein-Tyrosine Kinases, pubmed-meshheading:15158089-Proto-Oncogene Proteins, pubmed-meshheading:15158089-Pyrroles, pubmed-meshheading:15158089-Receptor Protein-Tyrosine Kinases, pubmed-meshheading:15158089-Stem Cell Factor, pubmed-meshheading:15158089-fms-Like Tyrosine Kinase 3
pubmed:year
2004
pubmed:articleTitle
Effects of SU5416, a small molecule tyrosine kinase receptor inhibitor, on FLT3 expression and phosphorylation in patients with refractory acute myeloid leukemia.
pubmed:affiliation
Sugen Inc., South San Francisco, CA, USA.
pubmed:publicationType
Journal Article, Clinical Trial, Multicenter Study, Clinical Trial, Phase II