Linked Life Data

20931182

Source:http://linkedlifedata.com/resource/pubmed/id/20931182

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2-3
pubmed:dateCreated
2010-11-24
pubmed:abstractText
Medulloblastoma is a pediatric high-grade cerebellar malignancy derived from neuronal precursors. Although electrophysiologic characteristics of cerebellar granule neurons at all stages of cell development have been well described, such characterization has not been reported for medulloblastoma. In this study we attempt to characterize important electrophysiologic features of medulloblastoma that may distinguish it from the surrounding cerebellum. Using patient-derived cell lines and tumor tissues, we show that medulloblastoma cells have no inward Na+ current or transient K+ current involved in action potential generation and propagation, typically seen in granule neurons. Expression and function of calcium-activated, large-conductance K+ channels are diminished in medulloblastoma, judged by electrophysiology and Western analysis. The resting membrane potential of medulloblastoma cells in culture is quite depolarized compared to granule neurons. Interestingly, medulloblastoma cells express small, fast-inactivating calcium currents consistent with T-type calcium channels, but these channels are activated only from hyperpolarized potentials, which are unlikely to occur. Additionally, a background acid-sensitive K+ current is present with features characteristic of TASK1 or TASK3 channels, such as inhibition by ruthenium red. Western analysis confirms expression of TASK1 and TASK3. In describing the electrophysiologic characteristics of medulloblastoma, one can see features that resemble other high-grade malignancies as opposed to normal cerebellar granule neurons. This supports the notion that the malignant phenotype of medulloblastoma is characterized by unique changes in ion channel expression.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
1432-1424
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
237
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
59-69
pubmed:meshHeading
pubmed:year
2010
pubmed:articleTitle
Biophysical properties of human medulloblastoma cells.
pubmed:affiliation
Department of Pediatrics, University of Alabama School of Medicine, 1719 6th Ave. S., CIRC 252A, Birmingham, AL 35294, USA.
pubmed:publicationType
Journal Article, Research Support, N.I.H., Extramural