Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2009-4-16
pubmed:abstractText
Prostate cancer is one of the most prominent malignancies of elderly males. The growth of normal prostate and prostate cancer (PCa) cells depend on functional androgen receptor (AR), a ligand controlled transcription factor and member of the nuclear receptor superfamily. Binding of agonistic ligand enhances the transactivation function of AR and hence promotes the growth of prostate epithelial cells. We have earlier shown that AR antagonistic ligands such as cyproterone acetate (CPA) promote the recruitment of transcriptional corepressors such as silencing mediator of retinoid and thyroid receptor (SMRT) leading to repression of AR transactivation in non-PCa cells. Unfortunately, however, in LNCaP PCa cells, CPA functions as an agonist and thereby increases AR transactivation function. Here, we show that activated MEK signaling cascade inhibits functional recruitment of corepressor SMRT to CPA-bound AR in PCa cells. Chemical blockade of MEK kinase using a specific inhibitor U0126 increases the interaction and hence repression of AR by the corepressor SMRT in LNCaP PCa cells. This inhibition also results in enhanced antagonistic behavior of CPA as assessed by reporter and cell-growth assays. Moreover, the growth of LNCaP cells stably overexpressing SMRT was more robustly inhibited in the presence of CPA and U1026. In line with this, the growth rate of LNCaP cells was decelerated in the presence of both CPA and U0126. This suggests that activated MEK signaling pathway attenuates the functional recruitment of corepressor SMRT to AR induced by antagonists and thus indicates the important role of corepressors in mediating repression of both AR transactivation and PCa cell growth by antagonists. Furthermore, these findings suggest that combining receptor antagonists with signaling inhibitors could be a beneficial approach for PCa treatment.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/AR protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Androgen Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Butadienes, http://linkedlifedata.com/resource/pubmed/chemical/Cyproterone Acetate, http://linkedlifedata.com/resource/pubmed/chemical/DNA-Binding Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Ligands, http://linkedlifedata.com/resource/pubmed/chemical/NCOR2 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Nitriles, http://linkedlifedata.com/resource/pubmed/chemical/Nuclear Receptor Co-Repressor 2, http://linkedlifedata.com/resource/pubmed/chemical/Prostate-Specific Antigen, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Androgen, http://linkedlifedata.com/resource/pubmed/chemical/Repressor Proteins, http://linkedlifedata.com/resource/pubmed/chemical/U 0126
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
1479-6813
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
42
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
429-35
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:19223455-Androgen Antagonists, pubmed-meshheading:19223455-Butadienes, pubmed-meshheading:19223455-Cell Line, Tumor, pubmed-meshheading:19223455-Cell Proliferation, pubmed-meshheading:19223455-Cyproterone Acetate, pubmed-meshheading:19223455-DNA-Binding Proteins, pubmed-meshheading:19223455-Enhancer Elements, Genetic, pubmed-meshheading:19223455-Gene Expression Regulation, Neoplastic, pubmed-meshheading:19223455-Humans, pubmed-meshheading:19223455-Ligands, pubmed-meshheading:19223455-MAP Kinase Signaling System, pubmed-meshheading:19223455-Male, pubmed-meshheading:19223455-Neoplastic Stem Cells, pubmed-meshheading:19223455-Nitriles, pubmed-meshheading:19223455-Nuclear Receptor Co-Repressor 2, pubmed-meshheading:19223455-Prostate-Specific Antigen, pubmed-meshheading:19223455-Prostatic Neoplasms, pubmed-meshheading:19223455-Protein Binding, pubmed-meshheading:19223455-Receptors, Androgen, pubmed-meshheading:19223455-Repressor Proteins, pubmed-meshheading:19223455-Transcriptional Activation
pubmed:year
2009
pubmed:articleTitle
Inhibition of MAPK-signaling pathway promotes the interaction of the corepressor SMRT with the human androgen receptor and mediates repression of prostate cancer cell growth in the presence of antiandrogens.
pubmed:affiliation
Institute of Human Genetics and Anthropology, Jena University Hospital, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't