Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
19
pubmed:dateCreated
2006-11-19
pubmed:abstractText
Patients with blast crisis (BC) CML frequently become resistant to Imatinib, a Bcr-Abl tyrosine kinase-targeting agent. Eg5, a microtubule-associated motor protein has been described to be highly expressed in BC CML by microarray analysis (Nowicki et al., Oncogene 2003; 22:3952-63). We investigated the regulation of Eg5 by Bcr-Abl tyrosine kinase and its potential as a therapeutic target in BC CML. Eg5 was highly expressed in all Philadelphia chromosome positive (Ph(+)) cell lines and BC CML patient samples. Inhibition of Bcr-Abl by Imatinib downregulated Eg5 expression in Imatinib-sensitive KBM5 and HL-60p185 cells, but not in Imatinib-resistant KBM5-STI571, harboring a T315I mutation, and Bcr-Abl-negative HL-60 cells. Blocking Eg5 expression with antisense oligonucleotide (Eg5-ASO) or inhibiting its activity with the small-molecule Eg5 inhibitor, S-trityl-L-cysteine induced G(2)/M cell cycle block and subsequent cell death in both Imatinib-sensitive and -resistant cells. Further, Eg5-ASO treatment of SCID mice harboring KBM5 cell xenografts significantly prolonged the median survival of the animals (p = 0.03). Our findings suggest that Eg5 is downstream of and regulated by Bcr-Abl tyrosine kinase in Philadelphia chromosome positive cells. Inhibition of Eg5 expression or its activity blocks cell cycle progression and induces cell death independent of the cellular response to Imatinib. Therefore, Eg5 could be a potential therapeutic target for the treatment of BC CML, in particular Imatinib-resistant BC CML.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1551-4005
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
5
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2223-9
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
Regulation and targeting of Eg5, a mitotic motor protein in blast crisis CML: overcoming imatinib resistance.
pubmed:affiliation
The University of Texas MD Anderson Cancer Center, Houston, Texas 77030, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural