Show simple item record

dc.contributor.authorMaranchie, Jodi K.
dc.contributor.authorZhan, Ye
dc.date2022-08-11T08:09:50.000
dc.date.accessioned2022-08-23T16:45:31Z
dc.date.available2022-08-23T16:45:31Z
dc.date.issued2005-10-19
dc.date.submitted2008-06-18
dc.identifier.citationCancer Res. 2005 Oct 15;65(20):9190-3. <a href="http://dx.doi.org/10.1158/0008-5472.CAN-05-2105">Link to article on publisher's site</a>
dc.identifier.issn0008-5472 (Print)
dc.identifier.doi10.1158/0008-5472.CAN-05-2105
dc.identifier.pmid16230378
dc.identifier.urihttp://hdl.handle.net/20.500.14038/40697
dc.description.abstractInactivation of the von Hippel-Lindau tumor suppressor (VHL) is an early event in >60% of sporadic clear cell renal cell carcinoma (RCC). Loss of VHL E3 ubiquitin ligase function results in accumulation of the alpha-subunit of the hypoxia-inducible heterodimeric transcription factor (HIF-alpha) and transcription of an array of genes including vascular endothelial growth factor, transforming growth factor-alpha, and erythropoietin. Studies have shown that HIF-alpha can be alternatively activated by reactive oxygen species. Nox4 is an NADP(H) oxidase that generates signaling levels of superoxide and is found in greatest abundance in the distal renal tubules. To determine if Nox4 contributes to HIF activity in RCC, we examined the impact of Nox4 expression on HIF-alpha expression and transactivation. We report here that small inhibitory RNA (siRNA) knockdown of Nox4 in 786-0 human renal tumor cells expressing empty vector (PRC) or wild-type VHL (WT) results in 50% decrease in intracellular reactive oxygen species as measured by a fluorescent 2',7'-dichlorofluorescin diacetate assay, and >85% reduction in HIF2-alpha mRNA and protein levels by quantitative reverse transcription-PCR and Western blot analysis. Furthermore, expression of the HIF target genes, vascular endothelial growth factor, transforming growth factor-alpha, and Glut-1 was abrogated by 93%, 74%, and 99%, respectively, after stable transfection with Nox4 siRNA relative to nontargeting siRNA, as determined by quantitative reverse transcription-PCR. Thus, renal Nox4 expression is essential for full HIF2-alpha expression and activity in 786-0 renal tumor cells, even in the absence of functional VHL. We propose the use of Nox4 as a target in the treatment of clear cell RCC.
dc.language.isoen_US
dc.relation<a href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=16230378&dopt=Abstract">Link to article in PubMed</a>
dc.subjectAmino Acid Sequence
dc.subjectBasic Helix-Loop-Helix Transcription Factors
dc.subjectCarcinoma, Renal Cell
dc.subjectGene Expression Regulation, Neoplastic
dc.subjectHela Cells
dc.subjectHumans
dc.subjectKidney Neoplasms
dc.subjectMolecular Sequence Data
dc.subjectNADPH Oxidase
dc.subjectRNA, Small Interfering
dc.subjectReactive Oxygen Species
dc.subjectTrans-Activation (Genetics)
dc.subjectTransfection
dc.subjectTransforming Growth Factor alpha
dc.subjectVascular Endothelial Growth Factor A
dc.subjectVon Hippel-Lindau Tumor Suppressor Protein
dc.subjectLife Sciences
dc.subjectMedicine and Health Sciences
dc.titleNox4 is critical for hypoxia-inducible factor 2-alpha transcriptional activity in von Hippel-Lindau-deficient renal cell carcinoma
dc.typeJournal Article
dc.source.journaltitleCancer research
dc.source.volume65
dc.source.issue20
dc.identifier.legacyfulltexthttps://escholarship.umassmed.edu/cgi/viewcontent.cgi?article=1349&amp;context=oapubs&amp;unstamped=1
dc.identifier.legacycoverpagehttps://escholarship.umassmed.edu/oapubs/350
dc.identifier.contextkey533058
refterms.dateFOA2022-08-23T16:45:31Z
html.description.abstract<p>Inactivation of the von Hippel-Lindau tumor suppressor (VHL) is an early event in >60% of sporadic clear cell renal cell carcinoma (RCC). Loss of VHL E3 ubiquitin ligase function results in accumulation of the alpha-subunit of the hypoxia-inducible heterodimeric transcription factor (HIF-alpha) and transcription of an array of genes including vascular endothelial growth factor, transforming growth factor-alpha, and erythropoietin. Studies have shown that HIF-alpha can be alternatively activated by reactive oxygen species. Nox4 is an NADP(H) oxidase that generates signaling levels of superoxide and is found in greatest abundance in the distal renal tubules. To determine if Nox4 contributes to HIF activity in RCC, we examined the impact of Nox4 expression on HIF-alpha expression and transactivation. We report here that small inhibitory RNA (siRNA) knockdown of Nox4 in 786-0 human renal tumor cells expressing empty vector (PRC) or wild-type VHL (WT) results in 50% decrease in intracellular reactive oxygen species as measured by a fluorescent 2',7'-dichlorofluorescin diacetate assay, and >85% reduction in HIF2-alpha mRNA and protein levels by quantitative reverse transcription-PCR and Western blot analysis. Furthermore, expression of the HIF target genes, vascular endothelial growth factor, transforming growth factor-alpha, and Glut-1 was abrogated by 93%, 74%, and 99%, respectively, after stable transfection with Nox4 siRNA relative to nontargeting siRNA, as determined by quantitative reverse transcription-PCR. Thus, renal Nox4 expression is essential for full HIF2-alpha expression and activity in 786-0 renal tumor cells, even in the absence of functional VHL. We propose the use of Nox4 as a target in the treatment of clear cell RCC.</p>
dc.identifier.submissionpathoapubs/350
dc.contributor.departmentDepartments of Surgery and Cell Biology
dc.source.pages9190-3


Files in this item

Thumbnail
Name:
16230378.pdf
Size:
244.3Kb
Format:
PDF

This item appears in the following Collection(s)

Show simple item record