Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2011-5-27
pubmed:abstractText
Gemcitabine (2'-deoxy-2', 2'-difluorocytidine; Gem) is a nucleoside anti-metabolite and is commonly used for treating various human cancers including human bladder carcinoma. Gemcitabine not only functions as a suicide nucleoside analog but also inhibits DNA polymerase activity and results in the termination of chain elongation. Using 2-dimensional gel electrophoresis analysis, a Gem-induced protein was identified as UBE2M (a.k.a. UBC12), a NEDD8 conjugation E2 enzyme which contributes to protein degradation. Gem induced UBE2M expression at both RNA and protein levels in several human cancer cell lines. The induction of UBE2M by Gem was accompanied by a reduction in p27(Kip1) protein levels, which could be restored by silencing UBE2M expression with siRNA or by treating cells with the proteasome inhibitor MG132, indicating that UBE2M mediates Gem-induced p27(Kip1) protein degradation. The induction of UBE2M and reduction of p27(Kip1) by Gem were prevented by the PI3K inhibitor LY294002. These results indicate that PI3K activity is necessary for Gem-induced UBE2M expression and that UBE2M facilitates degradation of p27(Kip1). Notably, silencing of UBE2M expression reduced Gem sensitivity in NTUB1 cells, suggesting that UBE2M mediates in part cell sensitivity to Gem, possibly by degradation of p27(Kip1). Analysis of Gem-resistant sub lines also showed that loss of UBE2M and increased p27(Kip1) expression were associated with the acquisition of drug resistance. In conclusion, our results demonstrate a role for UBE2M in mediating cytotoxicity of gemcitabine in human urothelial carcinoma cells while also suggesting a potential function of p27(Kip1) in drug resistance.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/2-(4-morpholinyl)-8-phenyl-4H-1-benz..., http://linkedlifedata.com/resource/pubmed/chemical/Antimetabolites, Antineoplastic, http://linkedlifedata.com/resource/pubmed/chemical/Chromones, http://linkedlifedata.com/resource/pubmed/chemical/Cyclin-Dependent Kinase Inhibitor..., http://linkedlifedata.com/resource/pubmed/chemical/Deoxycytidine, http://linkedlifedata.com/resource/pubmed/chemical/Elafin, http://linkedlifedata.com/resource/pubmed/chemical/Formazans, http://linkedlifedata.com/resource/pubmed/chemical/MTT formazan, http://linkedlifedata.com/resource/pubmed/chemical/Morpholines, http://linkedlifedata.com/resource/pubmed/chemical/PI3 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/RNA, Small Interfering, http://linkedlifedata.com/resource/pubmed/chemical/Tetrazolium Salts, http://linkedlifedata.com/resource/pubmed/chemical/Ubiquitins, http://linkedlifedata.com/resource/pubmed/chemical/gemcitabine
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1873-2968
pubmed:author
pubmed:copyrightInfo
Copyright © 2011 Elsevier Inc. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
82
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
35-42
pubmed:meshHeading
pubmed-meshheading:21477582-Antimetabolites, Antineoplastic, pubmed-meshheading:21477582-Blotting, Western, pubmed-meshheading:21477582-Carcinoma, Transitional Cell, pubmed-meshheading:21477582-Cell Line, Tumor, pubmed-meshheading:21477582-Cell Survival, pubmed-meshheading:21477582-Chromones, pubmed-meshheading:21477582-Cyclin-Dependent Kinase Inhibitor p27, pubmed-meshheading:21477582-Deoxycytidine, pubmed-meshheading:21477582-Drug Screening Assays, Antitumor, pubmed-meshheading:21477582-Elafin, pubmed-meshheading:21477582-Formazans, pubmed-meshheading:21477582-Gene Expression Regulation, pubmed-meshheading:21477582-Gene Silencing, pubmed-meshheading:21477582-Humans, pubmed-meshheading:21477582-Morpholines, pubmed-meshheading:21477582-RNA, Small Interfering, pubmed-meshheading:21477582-Spectrometry, Mass, Electrospray Ionization, pubmed-meshheading:21477582-Tetrazolium Salts, pubmed-meshheading:21477582-Ubiquitins, pubmed-meshheading:21477582-Urinary Bladder Neoplasms
pubmed:year
2011
pubmed:articleTitle
UBE2M-mediated p27(Kip1) degradation in gemcitabine cytotoxicity.
pubmed:affiliation
Department of Medicine, Graduate Institute of Biochemistry, Kaohsiung Medical University, Taiwan. amhuang@kmu.edu.tw
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't