Linked Life Data

11423976

Source:http://linkedlifedata.com/resource/pubmed/id/11423976

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
25
pubmed:dateCreated
2001-6-25
pubmed:abstractText
We investigated the role of radiation-induced mitogen activated protein kinase (MAPK) pathway activity in the regulation of proliferation, cell survival and vascular endothelial growth factor (VEGF) production in primary astrocytes and in T9 and RT2 glioblastoma cells derived from Fisher 344 rats. In these cells, ionizing radiation (2 Gy) caused activation of the MAPK pathway which was blocked by specific inhibitor drugs. Blunting of radiation-induced MAPK activity weakly enhanced radiation-induced apoptosis 24 h after exposure in RT2 cells. Furthermore, blunting of MAPK activation weakly enhanced the ability of radiation to reduce RT2 cell growth in clonogenic growth assays. These findings argue that inhibition of MAPK signaling reduces proliferation and enhances cell killing by ionizing radiation in transformed astrocytes. Proliferation and survival of cancer cells has been linked in vivo to enhanced expression of angiogenic growth factors. Recently we demonstrated that the gene product of a novel rodent radiation-responsive gene, progression elevated gene 3 (PEG-3), could enhance vascular endothelial growth factor (VEGF) promoter activity in rodent fibroblasts, leading to increased VEGF protein levels and tumorigenic behavior in vivo. Thus PEG-3 and VEGF expression could be expected to directly correlate with the oncogenic potential of transformed cells. RT2 cells expressed more PEG-3 and VEGF protein than T9 cells, and were more tumorigenic in vivo than T9 cells. Radiation activated the PEG-3 promoter via MAPK signaling and ectopic over-expression of PEG-3 enhanced both basal MAPK activity and basal VEGF promoter activity. Basal MAPK activity partially correlated with basal VEGF promoter activity and VEGF protein levels in primary astrocytes, T9 and RT2 cells. Radiation increased the activity of the VEGF promoter and VEGF protein levels in primary astrocytes, T9 and RT2 cells which were dependent upon MAPK function. Furthermore, inhibition of AP-1 transcription factor signaling by dominant negative c-Jun (TAM67) also significantly reduced basal, and to a lesser extent radiation-induced, VEGF promoter function in RT2 cells. Collectively, our data demonstrate that radiation-induced MAPK signaling can both protect cells from radiation-induced cell death as well as enhance protein levels of pro-angiogenic factors such as VEGF. Enhanced VEGF expression in RT2 cells may be mediated via MAPK and JNK pathway signaling which converges upon the AP-1 transcription factor complex.
pubmed:grant
pubmed:commentsCorrections
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Amino Acid Chloromethyl Ketones, http://linkedlifedata.com/resource/pubmed/chemical/Antigens, Differentiation, http://linkedlifedata.com/resource/pubmed/chemical/Endothelial Growth Factors, http://linkedlifedata.com/resource/pubmed/chemical/Flavonoids, http://linkedlifedata.com/resource/pubmed/chemical/Lymphokines, http://linkedlifedata.com/resource/pubmed/chemical/Mitogen-Activated Protein Kinases, http://linkedlifedata.com/resource/pubmed/chemical/Myd116 protein, rat, http://linkedlifedata.com/resource/pubmed/chemical/Neoplasm Proteins, http://linkedlifedata.com/resource/pubmed/chemical/PD 98059, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins, http://linkedlifedata.com/resource/pubmed/chemical/Proto-Oncogene Proteins c-jun, http://linkedlifedata.com/resource/pubmed/chemical/Transcription Factor AP-1, http://linkedlifedata.com/resource/pubmed/chemical/Vascular Endothelial Growth Factor A, http://linkedlifedata.com/resource/pubmed/chemical/Vascular Endothelial Growth Factors, http://linkedlifedata.com/resource/pubmed/chemical/benzyloxycarbonylvalyl-alanyl-aspart...
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0950-9232
pubmed:author
pubmed:issnType
Print
pubmed:day
31
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3266-80
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed-meshheading:11423976-Amino Acid Chloromethyl Ketones, pubmed-meshheading:11423976-Animals, pubmed-meshheading:11423976-Antigens, Differentiation, pubmed-meshheading:11423976-Apoptosis, pubmed-meshheading:11423976-Astrocytes, pubmed-meshheading:11423976-Cell Survival, pubmed-meshheading:11423976-Clone Cells, pubmed-meshheading:11423976-Endothelial Growth Factors, pubmed-meshheading:11423976-Flavonoids, pubmed-meshheading:11423976-Glioblastoma, pubmed-meshheading:11423976-Glioma, pubmed-meshheading:11423976-Lymphokines, pubmed-meshheading:11423976-Mitogen-Activated Protein Kinases, pubmed-meshheading:11423976-Neoplasm Proteins, pubmed-meshheading:11423976-Proto-Oncogene Proteins, pubmed-meshheading:11423976-Proto-Oncogene Proteins c-jun, pubmed-meshheading:11423976-Radiation, Ionizing, pubmed-meshheading:11423976-Rats, pubmed-meshheading:11423976-Rats, Inbred F344, pubmed-meshheading:11423976-Signal Transduction, pubmed-meshheading:11423976-Transcription Factor AP-1, pubmed-meshheading:11423976-Tumor Cells, Cultured, pubmed-meshheading:11423976-Vascular Endothelial Growth Factor A, pubmed-meshheading:11423976-Vascular Endothelial Growth Factors
pubmed:year
2001
pubmed:articleTitle
Ionizing radiation modulates vascular endothelial growth factor (VEGF) expression through multiple mitogen activated protein kinase dependent pathways.
pubmed:affiliation
Department of Radiation Oncology, Medical College of Virginia, Virginia Commonwealth University, Richmond, Virginia, VA 23298, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't