Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
2006-2-7
pubmed:abstractText
Reactive oxygen species (ROS) signal cascades involved in cell growth, cell death, mitogenesis, angiogenesis and carcinogenesis. ROS are produced as a byproduct of oxidative phosphorylation (OXPHOS) in the mitochondria. It is estimated that 2-4% of the oxygen consumed during OXPHOS is converted to ROS. Besides mitochondria, NADPH-oxidase 1 (Nox1) also generates a significant amount of ROS in the cell. In this paper, we tested the hypothesis that mitochondria control Nox 1 redox signaling and the loss of control of this signaling contributes to tumorigenesis. We analyzed Nox1 expression in a mitochondrial gene knockout (rho(0)) cell line and in the isogenic cybrid cell line in which mitochondrial genes were restored by transfer of wild type mitochondria into rho(0) cells. Our study revealed, for the first time, that the inactivation of mitochondrial genes leads to down-regulation of Nox1 and that the transfer of wild type mitochondrial genes restored the Nox1 expression to a level comparable to that in the parental cell line. Consistent with Nox1 down-regulation, we found that rho(0) cells contained low levels of superoxide anion and that superoxide levels reversed to parental levels in cybrid cells when Nox1 expression was restored by transfer of wild type mitochondria. Increasing mitochondrial superoxide levels also increased the expression of Nox1 in parental cells. Confocal microscopy studies revealed that Nox1 localizes in the mitochondria. Nox1 was highly expressed in breast (86%) and ovarian (71%) tumors and that its expression positively correlated with expression of cytochrome C oxidase encoded by mtDNA. Our study, described in this paper demonstrates the existence of cross talk between the mitochondria and NADPH oxidase. Furthermore, our studies suggest that mitochondria control Nox1 redox signaling and the loss of control of this signaling contributes to breast and ovarian tumorigenesis.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
1538-4047
pubmed:author
pubmed:issnType
Print
pubmed:volume
4
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1367-73
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Cross talk between mitochondria and superoxide generating NADPH oxidase in breast and ovarian tumors.
pubmed:affiliation
Department of Cancer Genetics, Roswell Park Cancer Institute, Buffalo, New York 14263, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't, Research Support, N.I.H., Extramural