Linked Life Data

17016641

Source:http://linkedlifedata.com/resource/pubmed/id/17016641

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2006-10-3
pubmed:abstractText
Development of new molecular target therapeutic agents is expected to improve clinical outcome, ideally with efficacy in both single and combined treatment modalities. Because of the potential for affecting multiple signaling pathways, inhibition of the molecular chaperone heat shock protein 90 (Hsp90) may provide a strategy for enhancing tumor cell radiation sensitivity. Therefore, we have investigated the effects of Hsp90 inhibitor 17-Allylamino-17-demethoxygeldanamycin (17-AAG) on radiation sensitivity of human tumor cells in vitro. We evaluated the effects of 17-AAG using oral squamous cell carcinoma (OSCC) cell lines (HSC2, HSC3 and HSC4), including two types of SAS cells with a wild-type (SAS/neo), or a mutated p53 status (SAS/Trp248). Apoptosis and clonogenic survival were examined after exposure of the cells to radiation. For mechanistic insight, we analyzed cell cycle, several signaling factors and molecular markers including Akt, Raf-1, p38 MAPK, Cdc25B, Cdc25C, Cdk2 and p21. Treatment of OSCC cell lines with 17-AAG resulted in cytotoxicity and, when combined with radiation, enhanced the radiation response. However, the responses depended on p53 status. 17-AAG enhanced the radiation sensitivity significantly and induced apoptosis in the SAS/neo cell which has a wild-type p53. But the radiation sensitizing effect of 17-AAG was limited in the SAS/Trp248 cell which has a mutated p53. We also measured the total levels of several prosurvival and cell cycle signaling proteins. Akt, Raf-1 and Cdc25C expression were down-regulated in 17-AAG-treated cells. These data indicate that 17-AAG inhibits the proliferation and enhances the radiation sensitivity of human OSCC cells in various levels. However, enhancement of radiation sensitivity by the Hsp90 inhibitor depended on p53 status. Therefore, Hsp90 therapy combined with radiation might synergize with conventional therapies in patients with wild-type p53.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
1019-6439
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1111-7
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
P53-dependent radiosensitizing effects of Hsp90 inhibitor 17-allylamino-17-demethoxygeldanamycin on human oral squamous cell carcinoma cell lines.
pubmed:affiliation
Department of Oral and Maxillofacial Surgery, Showa University school of Dentistry, Tokyo 145-8515, Japan. shintani@senzoku.showa-u.ac.jp
pubmed:publicationType
Journal Article