Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
21
pubmed:dateCreated
2002-11-4
pubmed:abstractText
Whereas hydroxyflutamide (HF) has been used as an antiandrogen to block androgen-stimulated prostate tumor growth, the antiandrogen withdrawal syndrome that allows antiandrogens to stimulate prostate tumor growth still occurs in many patients treated with androgen ablation therapy. This was previously explained by mutations in the androgen receptor (AR) and/or modulation from AR coregulators, so that HF becomes an AR agonist. Using immunohistochemical analysis, we analyzed four prostate cancer patients undergoing androgen ablation therapy with flutamide and compared their phospho-extracellular signal-regulated kinase 1/2 levels in prostate cancer biopsies before receiving HF and after experiencing disease progression while taking HF. We found a significant increase of activated mitogen-activated protein (MAP) kinase in prostate tumors from patients receiving HF during androgen ablation therapy. In vitro studies showed that HF induced a rapid activation of the Ras/MAP kinase pathway in human prostate cancer DU145 cells which lack the AR, as well as in PC-3AR2 and CWR22 cells which express the AR. Cycloheximide failed to inhibit this activation, but both AG1478, an inhibitor of the epidermal growth factor receptor (EGF-R), and an EGF-R-neutralizing antibody blocked this HF-mediated activation of MAP kinase, which suggests that the activation of Ras/MAP kinase by HF is a membrane-initiated, non-AR-mediated, and nongenomic action. The consequence of this activation may result in increasing cell proliferation and cyclin D1 expression. This raises a concern for using HF in the complete-androgen-ablation therapy in prostate cancer treatment and provides a possible pathway that might contribute to the HF withdrawal syndrome.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Androgen Antagonists, http://linkedlifedata.com/resource/pubmed/chemical/Cyclin D1, http://linkedlifedata.com/resource/pubmed/chemical/Flutamide, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinase 1, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinase 3, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-raf, http://linkedlifedata.com/resource/pubmed/chemical/Receptor, Epidermal Growth Factor, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Androgen, http://linkedlifedata.com/resource/pubmed/chemical/Tyrphostins, http://linkedlifedata.com/resource/pubmed/chemical/hydroxyflutamide, http://linkedlifedata.com/resource/pubmed/chemical/ras Proteins, http://linkedlifedata.com/resource/pubmed/chemical/tyrphostin AG 1478
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
6039-44
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:12414626-Androgen Antagonists, pubmed-meshheading:12414626-Cell Division, pubmed-meshheading:12414626-Cyclin D1, pubmed-meshheading:12414626-Enzyme Activation, pubmed-meshheading:12414626-Flutamide, pubmed-meshheading:12414626-Humans, pubmed-meshheading:12414626-MAP Kinase Signaling System, pubmed-meshheading:12414626-Male, pubmed-meshheading:12414626-Mitogen-Activated Protein Kinase 1, pubmed-meshheading:12414626-Mitogen-Activated Protein Kinase 3, pubmed-meshheading:12414626-Mitogen-Activated Protein Kinases, pubmed-meshheading:12414626-Neoplasms, Hormone-Dependent, pubmed-meshheading:12414626-Phosphorylation, pubmed-meshheading:12414626-Prostatic Neoplasms, pubmed-meshheading:12414626-Proto-Oncogene Proteins c-raf, pubmed-meshheading:12414626-Receptor, Epidermal Growth Factor, pubmed-meshheading:12414626-Receptors, Androgen, pubmed-meshheading:12414626-Substance Withdrawal Syndrome, pubmed-meshheading:12414626-Tyrphostins, pubmed-meshheading:12414626-ras Proteins
pubmed:year
2002
pubmed:articleTitle
Activation of mitogen-activated protein kinase pathway by the antiandrogen hydroxyflutamide in androgen receptor-negative prostate cancer cells.
pubmed:affiliation
George Whipple Laboratory for Cancer Research, Department of Pathology, and The Cancer Center, University of Rochester Medical Center, New York 14642, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't