Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2011-6-2
pubmed:abstractText
We have previously demonstrated the roles of RhoA, Rac1, and Cdc42 in hypoxia-driven angiogenesis. However, the role of oncogenes in hypoxia signaling is poorly understood. Given the importance of Rho proteins in the hypoxic response, we hypothesized that Rho family members could act as mediators of hypoxic signal transduction. We investigated the cross-talk between hypoxia and oncogene-driven signal transduction pathways and explored the role of Rac1 on hypoxia-induced hypoxia-inducible factor (HIF)-1? and VEGF expression. Since the phosphatidylinositol 3'-kinase (PI3K) pathway is involved in signal transduction of many oncogenes, we explored the role of PI3K on Rac1-mediated expression of HIF-1? and VEGF in hypoxia. We showed that LY-294002, a PI3K inhibitor, suppressed HIF-1? and VEGF induction under hypoxic conditions by up to 50%. Activation of Rac1 resulted in an upregulation of hypoxia-induced HIF-1? expression, which was blocked by LY-294002. These data suggested that Rac1 is an intermediate in the PI3K-mediated induction of HIF-1?. Interestingly, there was a significant downregulation of the tumor suppressor genes p53 and von Hippel-Lindau tumor suppressor (VHL) in cells expressing a constitutively active form of Rac1. Rac1-mediated inhibition of p53 and VHL could therefore be implicated in the upregulation of HIF-1? expression.
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/Chromones, http://linkedlifedata.com/resource/pubmed/chemical/Enzyme Inhibitors, http://linkedlifedata.com/resource/pubmed/chemical/HIF1A protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Hypoxia-Inducible Factor 1, alpha..., http://linkedlifedata.com/resource/pubmed/chemical/Morpholines, http://linkedlifedata.com/resource/pubmed/chemical/Phosphatidylinositol 3-Kinases, http://linkedlifedata.com/resource/pubmed/chemical/RAC1 protein, human, http://linkedlifedata.com/resource/pubmed/chemical/Tumor Suppressor Protein p53, http://linkedlifedata.com/resource/pubmed/chemical/Vascular Endothelial Growth Factor A, http://linkedlifedata.com/resource/pubmed/chemical/Von Hippel-Lindau Tumor Suppressor..., http://linkedlifedata.com/resource/pubmed/chemical/rac1 GTP-Binding Protein
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
1522-1539
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
300
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
H2169-76
pubmed:meshHeading
pubmed-meshheading:21357506-Anoxia, pubmed-meshheading:21357506-Cell Line, Tumor, pubmed-meshheading:21357506-Chromones, pubmed-meshheading:21357506-Enzyme Inhibitors, pubmed-meshheading:21357506-Gene Expression Regulation, Neoplastic, pubmed-meshheading:21357506-Humans, pubmed-meshheading:21357506-Hypoxia-Inducible Factor 1, alpha Subunit, pubmed-meshheading:21357506-Morpholines, pubmed-meshheading:21357506-Neovascularization, Pathologic, pubmed-meshheading:21357506-Phosphatidylinositol 3-Kinases, pubmed-meshheading:21357506-Signal Transduction, pubmed-meshheading:21357506-Stomach Neoplasms, pubmed-meshheading:21357506-Tumor Suppressor Protein p53, pubmed-meshheading:21357506-Vascular Endothelial Growth Factor A, pubmed-meshheading:21357506-Von Hippel-Lindau Tumor Suppressor Protein, pubmed-meshheading:21357506-rac1 GTP-Binding Protein
pubmed:year
2011
pubmed:articleTitle
Phosphatidylinositol 3'-kinase signaling pathway is essential for Rac1-induced hypoxia-inducible factor-1(alpha) and vascular endothelial growth factor expression.
pubmed:affiliation
Dept. of Clinical Oncology, Xijing Hospital, Fourth Military Medical Univ., Xi'an 710032, Shaanxi, People's Republic of China.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't