Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2009-8-31
pubmed:abstractText
The aim of this study is to evaluate the effect of heat shock protein 90 (Hsp90) inhibition, and to identify molecular pathways responsible for anti-proliferative effect on adult T cell leukemia/lymphoma (ATL) cells. For Hsp90 inhibition, we used geldanamycin derivates, 17-AAG (17-allylamino-17-demethoxygeldanamycin) and 17-DMAG (17-(dimethylaminoethylamino) 17-demethoxygeldanamycin) in this study. The inhibitory concentration (IC(50)) of 17-AAG in an ATL cell line, designated as TaY, and two HTLV-1 transformed cell lines (MT-2 and MT-4) was 300-700 nM, and that of 17-DMAG was 150-200nM. Fresh ATL cells obtained from patients were more sensitive to both 17-AAG and 17-DMAG. Gene expression analysis of TaY cells revealed up-regulation of HSPA1A encoding Hsp70, a hallmark of Hsp90 inhibition. Genes regulating cell proliferation or anti-apoptosis (i.e. BCL2 and BIRC5), genes related to cytokines or chemokines (i.e. IL9 and CCL27), and notably TCF7L2, a down-stream effecter of beta-catenin were remarkably down-regulated. Down-regulation of TCF7L2 mRNA was noted in the three cell lines and two patient specimens after Hsp90 inhibition. Hsp90 inhibitors dephosphorylate AKT, thereby, activate GSK-3beta, which phosphorylates beta-catenin for ubiquitination. This indicates the possibility that beta-catenin/TCF7L2 pathway plays an important role in Hsp90 inhibitor-induced cell death in ATL cells and HTLV-1 transformed cells. Our results have provided new insights into the complex molecular pharmacology of Hsp90 inhibitors, and suggest that Hsp90 inhibitors might be beneficial as anti-proliferative agents in treating ATL patients.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1872-7980
pubmed:author
pubmed:issnType
Electronic
pubmed:day
18
pubmed:volume
284
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
62-70
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:year
2009
pubmed:articleTitle
Anti-proliferative activity of heat shock protein (Hsp) 90 inhibitors via beta-catenin/TCF7L2 pathway in adult T cell leukemia cells.
pubmed:affiliation
First Department of Internal Medicine, Tokyo Medical University, Tokyo, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't