Searching accross hundreds of databases

Our searching services are busy right now. Your search will reload in five seconds.

X
Forgot Password

If you have forgotten your password you can enter your email here and get a temporary password sent to your email.

STAT3-iNOS Signaling Mediates EGFRvIII-Induced Glial Proliferation and Transformation.

Malignant gliomas, including glioblastoma multiforme, constitute the most common and aggressive primary brain tumors in adults. The transcription factor signal transducer and activator of transcription 3 (STAT3) plays an essential role in glioblastoma pathogenesis downstream of the major oncogenic protein epidermal growth factor receptor variant III (EGFRvIII). However, the critical gene targets of STAT3 that mediate EGFRvIII-induced glial transformation have remained unknown. Here, we identify inducible nitric oxide synthase (iNOS) as a novel target gene of STAT3 in EGFRvIII-expressing mouse astrocytes. Endogenous STAT3 occupies the endogenous iNOS promoter and stimulates iNOS transcription in EGFRvIII-expressing astrocytes. STAT3 does not appear to control iNOS transcription in astrocytes deficient in the major glioblastoma tumor suppressor protein phosphatase and tensin homolog (PTEN), suggesting that STAT3 regulates iNOS transcription specifically in EGFRvIII-expressing astrocytes. Importantly, inhibition of iNOS by distinct approaches, including knockdown by RNA interference, reduces cell population growth and invasiveness of EGFRvIII-expressing astrocytes. In addition, upon iNOS knockdown or administration of a small-molecule inhibitor of iNOS, EGFRvIII-expressing astrocytes form smaller tumors in vivo. These findings suggest that inhibition of iNOS may have potential therapeutic value for EGFRvIII-activated brain tumors.

Pubmed ID: 22674257 RIS Download

Mesh terms: Animals | Animals, Genetically Modified | Astrocytes | Binding Sites | Cell Proliferation | Cell Transformation, Neoplastic | Cells, Cultured | Chromatin Immunoprecipitation | Enzyme Inhibitors | Glioblastoma | Immunohistochemistry | Lentivirus | Mice | Neuroglia | Nitric Oxide Synthase Type II | PTEN Phosphohydrolase | Plasmids | Polymerase Chain Reaction | RNA Interference | Receptor, Epidermal Growth Factor | STAT3 Transcription Factor | Signal Transduction | Transcription, Genetic

Research resources used in this publication

Research tools detected in this publication

None found

Data used in this publication

None found

Associated grants

  • Agency: NINDS NIH HHS, Id: R01 NS064007
  • Agency: NIGMS NIH HHS, Id: T32 GM007753
  • Agency: NINDS NIH HHS, Id: NS064007
  • Agency: Canadian Institutes of Health Research, Id:

Publication data is provided by the National Library of Medicine ® and PubMed ®. Data is retrieved from PubMed ® on a weekly schedule. For terms and conditions see the National Library of Medicine Terms and Conditions.