title: The inhibition of KCa3.1 channels activity reduces cell motility in glioblastoma derived cancer stem cells.
abstract: In the present study we evaluated the expression of the intermediate conductance calcium-activated potassium (KCa3.1) channel in human glioblastoma stem-like cells (CSCs) and investigated its role in cell motility. While the KCa3.1 channel is not expressed in neuronal- and glial-derived tissues of healthy individuals, both the KCa3.1 mRNA and protein are present in the glioblastoma tumor population, and are significantly enhanced in CSCs derived from both established cell line U87MG and a primary cell line, FCN9. Consistent with these data, voltage-independent and TRAM-34 sensitive potassium currents imputable to the KCa3.1 channel were recorded in the murine GL261 cell line and several primary human glioblastoma cells lines. Moreover, a significantly higher KCa3.1 current was recorded in U87MG-CD133 positive cells as compared to the U87MG-CD133 negative subpopulation. Further, we found that the tumor cell motility is strongly associated with KCa3.1 channel expression. Blockade of the KCa3.1 channel with the specific inhibitor TRAM-34 has in fact a greater impact on the motility of CSCs (reduction of 75%), which express a high level of KCa3.1 channel, than on the FCN9 parental population (reduction of 32%), where the KCa3.1 channel is expressed at lower level. Similar results were also observed with the CSCs derived from U87MG. Because invasion of surrounding tissues is one of the main causes of treatment failure in glioblastoma, these findings can be relevant for future development of novel cancer therapeutic drugs.
authors.affiliation: Department of Medical-surgical Sciences and Biotechnologies, University of Rome "Sapienza", Latina, Italy.
authors.forename: Paola
authors.initials: P
authors.lastname: Ruggieri
authors.forename: Giorgio
authors.initials: G
authors.lastname: Mangino
authors.forename: Bernard
authors.initials: B
authors.lastname: Fioretti
authors.forename: Luigi
authors.initials: L
authors.lastname: Catacuzzeno
authors.forename: Rosa
authors.initials: R
authors.lastname: Puca
authors.forename: Donatella
authors.initials: D
authors.lastname: Ponti
authors.forename: Massimo
authors.initials: M
authors.lastname: Miscusi
authors.forename: Fabio
authors.initials: F
authors.lastname: Franciolini
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Ragona
authors.forename: Antonella
authors.initials: A
authors.lastname: Calogero
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000187:drug effects / Q000502:physiology*; D005455:Fluorescent Antibody Technique; D005909:Glioblastoma / Q000503:physiopathology*; D006801:Humans; D051660:Intermediate-Conductance Calcium-Activated Potassium Channels / Q000037:antagonists & inhibitors / Q000378:metabolism*; D051379:Mice; D014411:Neoplastic Stem Cells / Q000502:physiology*; D018408:Patch-Clamp Techniques; D011720:Pyrazoles / Q000494:pharmacology; D060888:Real-Time Polymerase Chain Reaction
chemical_list: D051660:Intermediate-Conductance Calcium-Activated Potassium Channels; C496923:KCNN4 protein, human; D011720:Pyrazoles; C411671:TRAM 34