Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells.

Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells. Research Abstract Details 

Research Abstract Table of Contents

Jump to the:

Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells. Abstract Text:

Voltage-dependent large-conductance Ca(2+)-activated K(+) channels, often referred to as BK channels, are a unique class of ion channels coupling intracellular chemical signaling to electrical signaling. BK channel expression has been shown to be up-regulated in human glioma biopsies, and expression levels correlate positively with the malignancy grade of the tumor. Glioma BK channels (gBK) are a splice variant of the hslo gene, are characterized by enhanced sensitivity to [Ca(2+)](i), and are the target of modulation by growth factors. By using the selective pharmacological BK channel inhibitor iberiotoxin, we examined the potential role of these channels in tumor growth. Cell survival assays examined the ability of glioma cells to grow in nominally serum-free medium. Under such conditions, BK channel inhibition by iberiotoxin caused a dose- and time-dependent decrease in cell number discernible as early as 72 hr after exposure and maximal growth inhibition after 4-5 days. FACS analysis shows that IbTX treatment arrests glioma cells in S phase of the cell cycle, whereupon cells undergo cell death. Interestingly, IbTX effects were nullified when cells were maintained in 7% fetal calf serum. Electrophysiological analysis, in conjunction with biotinylation studies, demonstrates that serum starvation caused a significant translocation of BK channel protein to the plasma membrane, corresponding to a two- to threefold increase in whole-cell conductance, but without a change in total gBK protein. Hence, expression of functional gBK channels appears to be regulated in a growth-factor-dependent manner, with enhanced surface expression promoting tumor cell growth under conditions of growth factor deprivation as might occur under in vivo conditions.

Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells. Publishing Authors By Initials

For similar abstracts research abstracts see: abstracts research

PUBMED ID PMID:

MEDLINE DATE:

Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells. Journal Published:

PUBLICATION TYPE: Research Support, U.S. Gov't,

Journal: Journal of neuroscience research

VOLUME: 78

Page Numbers: 224-34

Journal Abbreviation: J. Neurosci. Res.

ISSN: 0360-4012

DAY: 15

MONTH: Oct

YEAR: 2004

Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells. Information

Number of References:

LANGUAGE: eng

NlmUniqueID: 7600111

Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells. Keywords Mesh Terms:

KEYWORDS: Tetraethylammonium

MESH TERMS: pharmacology

Chemical & Substance for Abstract: Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells. Information

Substance Name: Tetraethylammonium

Registry Number: 66-40-0

Grant and Affiliation Information for Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells.

AFFILIATION: Department of Neurobiology, Civitan International Research Center, University of Alabama at Birmingham, Birmingham, Alabama, USA.

Country: United States

AGENCY: United States NINDS

GRANT: R01-NS36692

ACRONYM: NS

MEDLINETA: J Neurosci Res

REFSOURCE:

DATABASENAME:

ACCESSION NUMBER:

Number Hits: 0

Role for calcium-activated potassium channels BK in growth control of human malignant glioma cells Related Publications

• A glossary of modern health care economics: platitudes and principles gleaned from the first year's education of a new academic health care delivery center department head.
• A role for glutamate in growth and invasion of primary brain tumors.
• A role for ubiquitin in the spliceosome assembly pathway.
• A systematic review of juvenile-onset clinically amyopathic dermatomyositis.
• An inside job for siRNAs.
• An unexpected role for ion channels in brain tumor metastasis.
• Another view concerning the proposal to change the name of the American Academy of Dermatology.
• Antibodies inside our keratinocytes?
• Autocrine glutamate signaling promotes glioma cell invasion.
• BK channels are linked to inositol 1,4,5-triphosphate receptors via lipid rafts: a novel mechanism for coupling [Ca(2+)](i) to ion channel activation.
• Chronic penile ulceration in a 72-year-old man.
• ClC3 Is a Critical Regulator of the Cell Cycle in Normal and Malignant Glial Cells.
• Cutaneous lupus erythematosus: molecular and cellular basis of clinical findings.
• Cytoplasmic condensation is both necessary and sufficient to induce apoptotic cell death.
• Differential distribution of Kir4.1 in spinal cord astrocytes suggests regional differences in K+ homeostasis.
• Expression and function of water channels (aquaporins) in migrating malignant astrocytes.
• Extracellular glutamine is a critical modulator for regulatory volume increase in human glioma cells.
• Immunobiological significance of the Ro/SSA antigen-antibody system.
• Inhibition of transient receptor potential canonical channels impairs cytokinesis in human malignant gliomas.
• Questions answered and a $1 million question raised concerning lupus erythematosus tumidus: is routine laboratory surveillance testing during treatment with hydroxychloroquine for skin disease really necessary.
• Relative contribution of chloride channels and transporters to regulatory volume decrease in human glioma cells.
• Review: Statins reduce all-cause mortality in elderly patients with coronary heart disease.
• Role for calcium-activated potassium channels (BK) in growth control of human malignant glioma cells.
• Role of Kir4.1 channels in growth control of glia.
• Sarcoidal alopecia as a mimic of discoid lupus erythematosus.
• Suicide by advance directive?
• The anticardiolipin syndrome. A new way to slice an old pie, or a new pie to slice?