Linked Life Data

11280780

Source:http://linkedlifedata.com/resource/pubmed/id/11280780

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
2001-3-30
pubmed:abstractText
Tumors of the central nervous system (CNS) often have sustained expression of labile genes, including angiogenic growth factors and immunosuppressive cytokines, which promote tumor progression. Stabilization of the RNA transcripts for these genes, such as vascular endothelial growth factor (VEGF), is an important molecular pathway for this up-regulation. HuR, a member of the Elav family of RNA-binding proteins, has been implicated in this pathway through its binding to adenine and uridine (AU)-rich stability elements (ARE) located in the 3' untranslated regions (3'-UTRs) of the mRNA. Whereas three of the Elav family members (Hel-N1, HuC, and HuD) are restricted to young and mature neurons, HuR is more broadly expressed, including proliferating cells of the developing CNS. Because RNA stabilization of labile genes may promote tumor growth, we analyzed and compared the expression pattern of HuR in 35 freshly resected and cultured CNS tumors to determine whether there was any correlation with tumor grade or histological type. We found that HuR mRNA was consistently expressed in all of the tumors, regardless of cell origin or degree of malignancy. Using a novel HuR-specific polyclonal antibody, we found that strong HuR protein expression was limited to high-grade malignancies (glioblastoma multiforme and medulloblastoma). Within the glioblastoma multiforme, prominent HuR expression was also detected in perinecrotic areas in which angiogenic growth factors are up-regulated. To further define its role as a potential RNA stabilizer, we analyzed whether HuR could bind to the stability motifs within the 3'-UTRs of cytokines and growth factors linked to brain tumor progression. We used a novel ELISA-based RNA binding assay and focused on the 3'-UTRs of angiogenic factors VEGF, COX-2, and (interleukin) IL-8 as well as the immunomodulating factors IL-6, transforming growth factor (TGF)-beta and tumor necrosis factor (TNF)-alpha as potential RNA ligands. Our results indicated overall a very high binding affinity to these RNA targets. A comparison of these ligands revealed a hierarchy of binding affinities with the angiogenic factors, and TGF-beta showing the highest (Kd of 1.8-3.4 nM), and TNF-alpha the lowest (Kd of 18.3 nM). The expression pattern of HuR, coupled with the RNA binding data, strongly suggests a role for this protein in the posttranscriptional regulation of these genes in CNS tumors.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0008-5472
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
61
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
2154-61
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:11280780-3' Untranslated Regions, pubmed-meshheading:11280780-Adenine Nucleotides, pubmed-meshheading:11280780-Amino Acid Sequence, pubmed-meshheading:11280780-Angiogenesis Inducing Agents, pubmed-meshheading:11280780-Antigens, Surface, pubmed-meshheading:11280780-Astrocytoma, pubmed-meshheading:11280780-Brain Neoplasms, pubmed-meshheading:11280780-Cell Division, pubmed-meshheading:11280780-Cytokines, pubmed-meshheading:11280780-Disease Progression, pubmed-meshheading:11280780-Gene Expression Regulation, Neoplastic, pubmed-meshheading:11280780-Glioblastoma, pubmed-meshheading:11280780-Humans, pubmed-meshheading:11280780-Medulloblastoma, pubmed-meshheading:11280780-Meningioma, pubmed-meshheading:11280780-Molecular Sequence Data, pubmed-meshheading:11280780-Neovascularization, Pathologic, pubmed-meshheading:11280780-RNA, Messenger, pubmed-meshheading:11280780-RNA-Binding Proteins, pubmed-meshheading:11280780-Uracil Nucleotides
pubmed:year
2001
pubmed:articleTitle
HuR, a RNA stability factor, is expressed in malignant brain tumors and binds to adenine- and uridine-rich elements within the 3' untranslated regions of cytokine and angiogenic factor mRNAs.
pubmed:affiliation
Department of Neurology, University of Alabama at Birmingham, 35233-7340, 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