Linked Life Data

11017880

Source:http://linkedlifedata.com/resource/pubmed/id/11017880

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
2000-11-28
pubmed:abstractText
The Na(+)/H(+) exchanger NHE1 is involved in intracellular pH homeostasis and cell volume regulation and accumulates with actin in the lamellipodia of fibroblasts. In order to determine the role of NHE1 following epithelial transformation and the acquisition of motile and invasive properties, we studied NHE1 expression in polarized MDCK cells, Moloney Sarcoma virus (MSV) transformed MDCK cells and an invasive MSV-MDCK cell variant (MSV-MDCK-INV). Expression of NHE1 was significantly increased in MSV-MDCK-INV cells relative to MSV-MDCK and MDCK cells. NHE1 was localized with b-actin to the tips of MSV-MDCK-INV cell pseudopodia by immunofluorescence. Sensitivity of NHE1-mediated (22)Na uptake to ethylisopropylamiloride, a specific inhibitor of NHE1, was increased in MSV-MDCK cells relative to MDCK cells. Changes in intracellular pH induced upon EIPA treatment were also of higher magnitude in MSV-MDCK and MSV-MDCK-INV cells compared to wild-type MDCK cells, especially in Hepes-buffered DMEM medium. Inhibition of NHE1 by 50 microM ethylisopropylamiloride induced the disassembly of actin stress fibers and redistribution of the actin cytoskeleton in all cell types. However, in MSV-MDCK-INV cells, the effect of ethylisopropylamiloride treatment was more pronounced and associated with the increased reversible detachment of the cells from the substrate. Videomicroscopy of MSV-MDCK-INV cells revealed that within 20 minutes of addition, ethylisopropylamiloride induced pseudopodial retraction and inhibited cell motility. The ability of ethylisopropylamiloride to prevent nocodazole-induced formation of actin stress fibers in MSV-MDCK cells was more pronounced in Hepes medium relative to NaHCO(3) medium, showing that NHE1 can regulate actin stress fiber assembly in transformed MSV-MDCK cells via its intracellular pH regulatory effect. These results implicate NHE1 in the regulation of the actin cytoskeleton dynamics necessary for the adhesion and pseudopodial protrusion of motile, invasive tumor cells.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9533
pubmed:author
pubmed:issnType
Print
pubmed:volume
113 ( Pt 20)
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3649-62
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed-meshheading:11017880-Actin Cytoskeleton, pubmed-meshheading:11017880-Actins, pubmed-meshheading:11017880-Amiloride, pubmed-meshheading:11017880-Animals, pubmed-meshheading:11017880-Cell Adhesion, pubmed-meshheading:11017880-Cell Line, pubmed-meshheading:11017880-Cell Line, Transformed, pubmed-meshheading:11017880-Cell Movement, pubmed-meshheading:11017880-Cell Size, pubmed-meshheading:11017880-Cell Transformation, Neoplastic, pubmed-meshheading:11017880-Dogs, pubmed-meshheading:11017880-Fluorescent Antibody Technique, Indirect, pubmed-meshheading:11017880-Hydrogen-Ion Concentration, pubmed-meshheading:11017880-Microscopy, Video, pubmed-meshheading:11017880-Nocodazole, pubmed-meshheading:11017880-Phenotype, pubmed-meshheading:11017880-Pseudopodia, pubmed-meshheading:11017880-Sodium-Hydrogen Antiporter, pubmed-meshheading:11017880-Stress Fibers
pubmed:year
2000
pubmed:articleTitle
Regulation of the formation of tumor cell pseudopodia by the Na(+)/H(+) exchanger NHE1.
pubmed:affiliation
Groupe de recherche en transport membranaire, Département de physiologie, Département de pathologie et biologie cellulaire and Département de physique, Université de Montréal, CP 6128, Succursale Centre-Ville Montréal, Québec H3C.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't