1
|
Ganser K, Stransky N, Abed T, Quintanilla-Martinez L, Gonzalez-Menendez I, Naumann U, Koch P, Krueger M, Ruth P, Huber SM, Eckert F. K Ca channel targeting impairs DNA repair and invasiveness of patient-derived glioblastoma stem cells in culture and orthotopic mouse xenografts which only in part is predictable by K Ca expression levels. Int J Cancer 2024. [PMID: 38938062 DOI: 10.1002/ijc.35064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 05/07/2024] [Accepted: 05/21/2024] [Indexed: 06/29/2024]
Abstract
Prognosis of glioblastoma patients is still poor despite multimodal therapy. The highly brain-infiltrating growth in concert with a pronounced therapy resistance particularly of mesenchymal glioblastoma stem-like cells (GSCs) has been proposed to contribute to therapy failure. Recently, we have shown that a mesenchymal-to-proneural mRNA signature of patient derived GSC-enriched (pGSC) cultures associates with in vitro radioresistance and gel invasion. Importantly, this pGSC mRNA signature is prognostic for patients' tumor recurrence pattern and overall survival. Two mesenchymal markers of the mRNA signature encode for IKCa and BKCa Ca2+-activated K+ channels. Therefore, we analyzed here the effect of IKCa- and BKCa-targeting concomitant to (fractionated) irradiation on radioresistance and glioblastoma spreading in pGSC cultures and in pGSC-derived orthotopic xenograft glioma mouse models. To this end, in vitro gel invasion, clonogenic survival, in vitro and in vivo residual DNA double strand breaks (DSBs), tumor growth, and brain invasion were assessed in the dependence on tumor irradiation and K+ channel targeting. As a result, the IKCa- and BKCa-blocker TRAM-34 and paxilline, respectively, increased number of residual DSBs and (numerically) decreased clonogenic survival in some but not in all IKCa- and BKCa-expressing pGSC cultures, respectively. In addition, BKCa- but not IKCa-blockade slowed-down gel invasion in vitro. Moreover, systemic administration of TRAM-34 or paxilline concomitant to fractionated tumor irradiation increased in the xenograft model(s) residual number of DSBs and attenuated glioblastoma brain invasion and (numerically) tumor growth. We conclude, that KCa-blockade concomitant to fractionated radiotherapy might be a promising new strategy in glioblastoma therapy.
Collapse
Affiliation(s)
- Katrin Ganser
- Department of Radiation Oncology, University Hospital of Tübingen, Tübingen, Germany
| | - Nicolai Stransky
- Department of Radiation Oncology, University Hospital of Tübingen, Tübingen, Germany
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Tayeb Abed
- Department of Radiation Oncology, University Hospital of Tübingen, Tübingen, Germany
| | - Leticia Quintanilla-Martinez
- Institute of Pathology and Neuropathology, Comprehensive Cancer Center, Eberhard Karls University of Tübingen, Tübingen, Germany
- Cluster of Excellence iFIT (EXC 2180), Image-Guided and Functionally Instructed Tumor Therapies, Eberhard Karls University, Tuebingen, Germany
| | - Irene Gonzalez-Menendez
- Institute of Pathology and Neuropathology, Comprehensive Cancer Center, Eberhard Karls University of Tübingen, Tübingen, Germany
- Cluster of Excellence iFIT (EXC 2180), Image-Guided and Functionally Instructed Tumor Therapies, Eberhard Karls University, Tuebingen, Germany
| | - Ulrike Naumann
- Molecular Neurooncology, Hertie Institute for Clinical Brain Research and Center Neurology, University of Tübingen, Tübingen, Germany
| | - Pierre Koch
- Department of Pharmaceutical/Medicinal Chemistry II, Institute of Pharmacy, University of Regensburg, Regensburg, Germany
| | - Marcel Krueger
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, University of Tübingen, Tübingen, Germany
| | - Peter Ruth
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Stephan M Huber
- Department of Radiation Oncology, University Hospital of Tübingen, Tübingen, Germany
| | - Franziska Eckert
- Department of Radiation Oncology, University Hospital of Tübingen, Tübingen, Germany
- Department of Radiation Oncology, Medical University Vienna, AKH, Comprehensive Cancer Center, Vienna, Austria
| |
Collapse
|
2
|
Guerriero C, Fanfarillo R, Mancini P, Sterbini V, Guarguaglini G, Sforna L, Michelucci A, Catacuzzeno L, Tata AM. M2 muscarinic receptors negatively modulate cell migration in human glioblastoma cells. Neurochem Int 2024; 174:105673. [PMID: 38185384 DOI: 10.1016/j.neuint.2023.105673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 12/17/2023] [Accepted: 12/29/2023] [Indexed: 01/09/2024]
Abstract
Glioblastoma (GB) is a very aggressive human brain tumor. The high growth potential and invasiveness make this tumor surgically and pharmacologically untreatable. Our previous work demonstrated that the activation of the M2 muscarinic acetylcholine receptors (M2 mAChRs) inhibited cell proliferation and survival in GB cell lines and in the cancer stem cells derived from human biopsies. The aim of the present study was to investigate the ability of M2 mAChR to modulate cell migration in two different GB cell lines: U87 and U251. By wound healing assay and single cell migration analysis performed by time-lapse microscopy, we demonstrated the ability of M2 mAChRs to negatively modulate cell migration in U251 but not in the U87 cell line. In order to explain the different effects observed in the two cell lines we have evaluated the possible involvement of the intermediate conductance calcium-activated potassium (IKCa) channel. IKCa channel is present in the GB cells, and it has been demonstrated to modulate cell migration. Using the perforated patch-clamp technique we have found that selective activation of M2 mAChR significantly reduced functional density of the IKCa current in U251 but not in U87 cells. To understand whether the M2 mAChR mediated reduction of ion channel density in the U251 cell line was relevant for the cell migration impairment, we tested the effects of TRAM-34, a selective inhibitor of the IKCa channel, in wound healing assay. We found that it was able to markedly reduce U251 cell migration and significantly decrease the number of invadopodia-like structure formations. These results suggest that only in U251 cells the reduced cell migration M2 mAChR-mediated might involve, at least in part, the IKCa channel.
Collapse
Affiliation(s)
- Claudia Guerriero
- Department of Biology and Biotechnologies Charles Darwin, Sapienza University of Rome, 00185, Rome, Italy.
| | - Rachele Fanfarillo
- Department of Biology and Biotechnologies Charles Darwin, Sapienza University of Rome, 00185, Rome, Italy.
| | - Patrizia Mancini
- Department Experimental Medicine, Sapienza University of Rome, 00185, Rome, Italy.
| | | | | | - Luigi Sforna
- Department of Chemistry Biology and Biotechnology, University of Perugia, 06123, Perugia, Italy.
| | - Antonio Michelucci
- Department of Chemistry Biology and Biotechnology, University of Perugia, 06123, Perugia, Italy.
| | - Luigi Catacuzzeno
- Department of Chemistry Biology and Biotechnology, University of Perugia, 06123, Perugia, Italy.
| | - Ada Maria Tata
- Department of Biology and Biotechnologies Charles Darwin, Sapienza University of Rome, 00185, Rome, Italy; Research Centre of Neurobiology Daniel Bovet, Sapienza University of Rome, 00185, Rome, Italy.
| |
Collapse
|
3
|
Michelucci A, Sforna L, Di Battista A, Franciolini F, Catacuzzeno L. Ca 2+ -activated K + channels regulate cell volume in human glioblastoma cells. J Cell Physiol 2023; 238:2120-2134. [PMID: 37431808 DOI: 10.1002/jcp.31072] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 06/10/2023] [Accepted: 06/20/2023] [Indexed: 07/12/2023]
Abstract
Glioblastoma (GBM), the most lethal form of brain tumors, bases its malignancy on the strong ability of its cells to migrate and invade the narrow spaces of healthy brain parenchyma. Cell migration and invasion are both critically dependent on changes in cell volume and shape driven by the transmembrane transport of osmotically important ions such as K+ and Cl- . However, while the Cl- channels participating in cell volume regulation have been clearly identified, the precise nature of the K+ channels involved is still uncertain. Using a combination of electrophysiological and imaging approaches in GBM U87-MG cells, we found that hypotonic-induced cell swelling triggered the opening of Ca2+ -activated K+ (KCa ) channels of large and intermediate conductance (BKCa and IKCa , respectively), both highly expressed in GBM cells. The influx of Ca2+ mediated by the hypotonic-induced activation of mechanosensitive channels was found to be a key step for opening both the BKCa and the IKCa channels. Finally, the activation of both KCa channels mediated by mechanosensitive channels was found to be essential for the development of the regulatory volume decrease following hypotonic shock. Taken together, these data indicate that KCa channels are the main K+ channels responsible for the volume regulation in U87-MG cells.
Collapse
Affiliation(s)
- Antonio Michelucci
- Department of Chemistry, Biology, and Biotechnology, University of Perugia, Perugia, Italy
| | - Luigi Sforna
- Department of Chemistry, Biology, and Biotechnology, University of Perugia, Perugia, Italy
| | - Angela Di Battista
- Department of Chemistry, Biology, and Biotechnology, University of Perugia, Perugia, Italy
| | - Fabio Franciolini
- Department of Chemistry, Biology, and Biotechnology, University of Perugia, Perugia, Italy
| | - Luigi Catacuzzeno
- Department of Chemistry, Biology, and Biotechnology, University of Perugia, Perugia, Italy
| |
Collapse
|
4
|
Pharmacological targeting of the mitochondrial calcium-dependent potassium channel KCa3.1 triggers cell death and reduces tumor growth and metastasis in vivo. Cell Death Dis 2022; 13:1055. [PMID: 36539400 PMCID: PMC9768205 DOI: 10.1038/s41419-022-05463-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Revised: 11/18/2022] [Accepted: 11/22/2022] [Indexed: 12/24/2022]
Abstract
Ion channels are non-conventional, druggable oncological targets. The intermediate-conductance calcium-dependent potassium channel (KCa3.1) is highly expressed in the plasma membrane and in the inner mitochondrial membrane (mitoKCa3.1) of various cancer cell lines. The role mitoKCa3.1 plays in cancer cells is still undefined. Here we report the synthesis and characterization of two mitochondria-targeted novel derivatives of a high-affinity KCa3.1 antagonist, TRAM-34, which retain the ability to block channel activity. The effects of these drugs were tested in melanoma, pancreatic ductal adenocarcinoma and breast cancer lines, as well as in vivo in two orthotopic models. We show that the mitochondria-targeted TRAM-34 derivatives induce release of mitochondrial reactive oxygen species, rapid depolarization of the mitochondrial membrane, fragmentation of the mitochondrial network. They trigger cancer cell death with an EC50 in the µM range, depending on channel expression. In contrast, inhibition of the plasma membrane KCa3.1 by membrane-impermeant Maurotoxin is without effect, indicating a specific role of mitoKCa3.1 in determining cell fate. At sub-lethal concentrations, pharmacological targeting of mitoKCa3.1 significantly reduced cancer cell migration by enhancing production of mitochondrial reactive oxygen species and nuclear factor-κB (NF-κB) activation, and by downregulating expression of Bcl-2 Nineteen kD-Interacting Protein (BNIP-3) and of Rho GTPase CDC-42. This signaling cascade finally leads to cytoskeletal reorganization and impaired migration. Overexpression of BNIP-3 or pharmacological modulation of NF-κB and CDC-42 prevented the migration-reducing effect of mitoTRAM-34. In orthotopic models of melanoma and pancreatic ductal adenocarcinoma, the tumors at sacrifice were 60% smaller in treated versus untreated animals. Metastasis of melanoma cells to lymph nodes was also drastically reduced. No signs of toxicity were observed. In summary, our results identify mitochondrial KCa3.1 as an unexpected player in cancer cell migration and show that its pharmacological targeting is efficient against both tumor growth and metastatic spread in vivo.
Collapse
|
5
|
Massenzio F, Cambiaghi M, Marchiotto F, Boriero D, Limatola C, D’Alessandro G, Buffelli M. In vivo morphological alterations of TAMs during KCa3.1 inhibition-by using in vivo two-photon time-lapse technology. Front Cell Neurosci 2022; 16:1002487. [PMID: 36589283 PMCID: PMC9798303 DOI: 10.3389/fncel.2022.1002487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2022] [Accepted: 11/25/2022] [Indexed: 12/23/2022] Open
Abstract
Tumor associated macrophages (TAMs) are the mostprevalent cells recruited in the tumor microenvironment (TME). Once recruited, TAMs acquire a pro-tumor phenotype characterized by a typical morphology: ameboid in the tumor core and with larger soma and thick branches in the tumor periphery. Targeting TAMs by reverting them to an anti-tumor phenotype is a promising strategy for cancer immunotherapy. Taking advantage of Cx3cr1GFP/WT heterozygous mice implanted with murine glioma GL261-RFP cells we investigated the role of Ca2+-activated K+ channel (KCa3.1) on the phenotypic shift of TAMs at the late stage of glioma growth through in vivo two-photon imaging. We demonstrated that TAMs respond promptly to KCa3.1 inhibition using a selective inhibitor of the channel (TRAM-34) in a time-dependent manner by boosting ramified projections attributable to a less hypertrophic phenotype in the tumor core. We also revealed a selective effect of drug treatment by reducing both glioma cells and TAMs in the tumor core with no interference with surrounding cells. Taken together, our data indicate a TRAM-34-dependent progressive morphological transformation of TAMs toward a ramified and anti-tumor phenotype, suggesting that the timing of KCa3.1 inhibition is a key point to allow beneficial effects on TAMs.
Collapse
Affiliation(s)
- Francesca Massenzio
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy,*Correspondence: Mario Buffelli Francesca Massenzio
| | - Marco Cambiaghi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Federica Marchiotto
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Diana Boriero
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy
| | - Cristina Limatola
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy,IRCCS Neuromed, Pozzilli, Italy
| | - Giuseppina D’Alessandro
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy,IRCCS Neuromed, Pozzilli, Italy
| | - Mario Buffelli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy,*Correspondence: Mario Buffelli Francesca Massenzio
| |
Collapse
|
6
|
Caglioti C, Palazzetti F, Monarca L, Lobello R, Ceccarini MR, Iannitti RG, Russo R, Ragonese F, Pennetta C, De Luca A, Codini M, Fioretti B. LY294002 Inhibits Intermediate Conductance Calcium-Activated Potassium (KCa3.1) Current in Human Glioblastoma Cells. Front Physiol 2022; 12:790922. [PMID: 35069252 PMCID: PMC8782274 DOI: 10.3389/fphys.2021.790922] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 11/30/2021] [Indexed: 11/16/2022] Open
Abstract
Glioblastomas (GBs) are among the most common tumors with high malignancy and invasiveness of the central nervous system. Several alterations in protein kinase and ion channel activity are involved to maintain the malignancy. Among them, phosphatidylinositol 3-kinase (PI3K) activity and intermediate conductance calcium-activated potassium (KCa3.1) current are involved in several aspects of GB biology. By using the electrophysiological approach and noise analysis, we observed that KCa3.1 channel activity is LY294002-sensitive and Wortmannin-resistant in accordance with the involvement of PI3K class IIβ (PI3KC2β). This modulation was observed also during the endogenous activation of KCa3.1 current with histamine. The principal action of PI3KC2β regulation was the reduction of open probability in intracellular free calcium saturating concentration. An explanation based on the “three-gate” model of the KCa3.1 channel by PI3KC2β was proposed. Based on the roles of KCa3.1 and PI3KC2β in GB biology, a therapeutic implication was suggested to prevent chemo- and radioresistance mechanisms.
Collapse
Affiliation(s)
- Concetta Caglioti
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Perugia, Italy.,Department of Medicine, Perugia Medical School, University of Perugia, Perugia, Italy
| | - Federico Palazzetti
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Perugia, Italy
| | - Lorenzo Monarca
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Perugia, Italy.,Department of Medicine, Perugia Medical School, University of Perugia, Perugia, Italy
| | | | | | | | - Roberta Russo
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Perugia, Italy
| | - Francesco Ragonese
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Perugia, Italy
| | - Chiara Pennetta
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Perugia, Italy
| | - Antonella De Luca
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Perugia, Italy
| | - Michela Codini
- Department of Pharmaceutical Sciences, University of Perugia, Perugia, Italy
| | - Bernard Fioretti
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Perugia, Italy
| |
Collapse
|
7
|
Catacuzzeno L, Sforna L, Esposito V, Limatola C, Franciolini F. Ion Channels in Glioma Malignancy. Rev Physiol Biochem Pharmacol 2020; 181:223-267. [DOI: 10.1007/112_2020_44] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
8
|
Manfroni G, Ragonese F, Monarca L, Astolfi A, Mancinelli L, Iannitti RG, Bastioli F, Barreca ML, Cecchetti V, Fioretti B. New Insights on KCa3.1 Channel Modulation. Curr Pharm Des 2020; 26:2096-2101. [PMID: 32175839 DOI: 10.2174/1381612826666200316152645] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2020] [Accepted: 03/11/2020] [Indexed: 11/22/2022]
Abstract
The human intermediate conductance calcium-activated potassium channel, KCa3.1, is involved in several pathophysiological conditions playing a critical role in cell secretory machinery and calcium signalling. The recent cryo-EM analysis provides new insights for understanding the modulation by both endogenous and pharmacological agents. A typical feature of this channel is the low open probability in saturating calcium concentrations and its modulation by potassium channel openers (KCOs), such as benzo imidazolone 1-EBIO, without changing calcium-dependent activation. In this paper, we proposed a model of KCOs action in the modulation of channel activity. The KCa3.1 channel has a very rich pharmacological profile with several classes of molecules that selectively interact with different binding sites of the channel. Among them, benzo imidazolones can be openers (positive modulators such as 1-EBIO, DC-EBIO) or blockers (negative modulators such as NS1619). Through computation modelling techniques, we identified the 1,4-benzothiazin-3-one as a promising scaffold to develop new KCa3.1 channel modulators. Further studies are needed to explore the potential use of 1-4 benzothiazine- 3-one in KCa3.1 modulation and its pharmacological application.
Collapse
Affiliation(s)
- Giuseppe Manfroni
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo, 1-06123-Perugia (PG), Italy
| | - Francesco Ragonese
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy.,Department of Experimental Medicine, Perugia Medical School, University of Perugia, Piazza Lucio Severi 1, 06132 Perugia, Italy
| | - Lorenzo Monarca
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy.,Department of Experimental Medicine, Perugia Medical School, University of Perugia, Piazza Lucio Severi 1, 06132 Perugia, Italy
| | - Andrea Astolfi
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo, 1-06123-Perugia (PG), Italy
| | - Loretta Mancinelli
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
| | | | | | - Maria L Barreca
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo, 1-06123-Perugia (PG), Italy
| | - Violetta Cecchetti
- Department of Pharmaceutical Sciences, University of Perugia, Via del Liceo, 1-06123-Perugia (PG), Italy
| | - Bernard Fioretti
- Department of Chemistry, Biology and Biotechnologies, University of Perugia, Via Elce di Sotto 8, 06123 Perugia, Italy
| |
Collapse
|
9
|
Ragonese F, Monarca L, Bastioli F, Arcuri C, Mancinelli L, Fioretti B. Silver ions promote blebs growth in U251 glioblastoma cell by activating nonselective cationic currents. Sci Rep 2019; 9:12898. [PMID: 31501459 PMCID: PMC6733836 DOI: 10.1038/s41598-019-49198-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 08/21/2019] [Indexed: 11/09/2022] Open
Abstract
Glioblastoma (GBM) is the most common and aggressive human brain cancer with low prognosis and therefore the discovery of new anticancer agents is needful. Sulfydryl reagents, such as silver, have been shown to induce membrane vesiculation in several cellular models through a mechanism that has not been yet completely clarified. Using U251 glioblastoma cells, we observed that silver induced irreversible bleb formation of the plasma membrane. This morphological event was anticipated by an increase of intracellular Ca2+ associated to extracellular Ca2+ influx. Accordingly, using patch-clamp whole cell recording during silver ion application, inward current/s (IAg) at -90 mV were detected and cells were permeable to Ca2+ and monovalent ions such as Na+. IAg activation and the intracellular Ca2+ increase promoted by silver ions (Ag+) were prevented by co-application of 20 µM cysteine and 300 µM DIDS (4,4'-Diisothiocyanatostilbene-2,2'-disulfonic acid), suggesting a critical role of thiol groups in the biological effects of silver ions. IAg was partially inhibited by 1 mM Gd3+, an unspecific inhibitor of cationic currents. Cysteine, Gd3+ and extracellular free Ca2+ solution completely abolished blebbing formation promoted by Ag+. Furthermore, extracellular Na+ ion replacement with TEA or an increase of extracellular tonicity by sucrose (100 mM) reduced both size and growth of membrane blebbing. Our data suggest that Ag+ promotes the formation necrotic blebs as consequence of the increase of intracellular Ca2+ and intracellular hydrostatic pressure associated to the activation of cationic currents. Since silver-induced blebs were less evident in benign glial human Müller MIO-M1 cells, silver compounds could represent new adjuvant to anticancer agents to improve GBM therapies.
Collapse
Affiliation(s)
- Francesco Ragonese
- Department of Chemistry, Biology and Biotechnologies, Via Elce di Sotto 8, University of Perugia, Perugia, Italy.,Department of Experimental Medicine, Piazzale Gambuli 1, University of Perugia, Perugia, Italy
| | - Lorenzo Monarca
- Department of Chemistry, Biology and Biotechnologies, Via Elce di Sotto 8, University of Perugia, Perugia, Italy
| | - Federica Bastioli
- Department of Chemistry, Biology and Biotechnologies, Via Elce di Sotto 8, University of Perugia, Perugia, Italy
| | - Cataldo Arcuri
- Department of Experimental Medicine, Piazzale Gambuli 1, University of Perugia, Perugia, Italy
| | - Loretta Mancinelli
- Department of Chemistry, Biology and Biotechnologies, Via Elce di Sotto 8, University of Perugia, Perugia, Italy
| | - Bernard Fioretti
- Department of Chemistry, Biology and Biotechnologies, Via Elce di Sotto 8, University of Perugia, Perugia, Italy.
| |
Collapse
|
10
|
Jin L, Li H, Wang J, Lin D, Yin K, Lin L, Lin Z, Lin G, Wang H, Ying X, Wang L, Zhang Y, Teng L. MicroRNA‐193a‐5p exerts a tumor suppressor role in glioblastoma via modulating NOVA1. J Cell Biochem 2018; 120:6188-6197. [PMID: 30304561 DOI: 10.1002/jcb.27906] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 09/25/2018] [Indexed: 12/27/2022]
Affiliation(s)
- Lingjiang Jin
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Huiyong Li
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Junyou Wang
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Da Lin
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Kang Yin
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Ligang Lin
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Zheng Lin
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Gaojun Lin
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Hui Wang
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Xiaowei Ying
- The Center for Cerebrovascular Disease The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Lisong Wang
- The Center for Cerebrovascular Disease The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Yongqiang Zhang
- The Center for Cerebrovascular Disease The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| | - Lingfang Teng
- Department of Neurosurgery The Affiliated Wenling Hospital of Wenzhou Medical University Wenling China
| |
Collapse
|
11
|
Barreto dos Santos N, Bonfanti AP, Rocha‐e‐Silva TAAD, da Silva PI, da Cruz‐Höfling MA, Verinaud L, Rapôso C. Venom of the
Phoneutria nigriventer
spider alters the cell cycle, viability, and migration of cancer cells. J Cell Physiol 2018; 234:1398-1415. [DOI: 10.1002/jcp.26935] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2018] [Accepted: 06/12/2018] [Indexed: 01/15/2023]
Affiliation(s)
- Natália Barreto dos Santos
- Departamento de Biologia Estrutural e Funcional Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP) Campinas Brazil
| | - Amanda Pires Bonfanti
- Departamento de Biologia Estrutural e Funcional Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP) Campinas Brazil
| | | | | | - Maria Alice da Cruz‐Höfling
- Departamento de Bioquímica e Biologia Tecidual Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP) Campinas Brazil
| | - Liana Verinaud
- Departamento de Biologia Estrutural e Funcional Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP) Campinas Brazil
| | - Catarina Rapôso
- Departamento de Biologia Estrutural e Funcional Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP) Campinas Brazil
| |
Collapse
|
12
|
Rosa P, Catacuzzeno L, Sforna L, Mangino G, Carlomagno S, Mincione G, Petrozza V, Ragona G, Franciolini F, Calogero A. BK channels blockage inhibits hypoxia-induced migration and chemoresistance to cisplatin in human glioblastoma cells. J Cell Physiol 2018; 233:6866-6877. [PMID: 29319175 DOI: 10.1002/jcp.26448] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Accepted: 01/05/2018] [Indexed: 12/25/2022]
Abstract
Glioblastoma (GBM) cells express large-conductance, calcium-activated potassium (BK) channels, whose activity is important for several critical aspects of the tumor, such as migration/invasion and cell death. GBMs are also characterized by a heavy hypoxic microenvironment that exacerbates tumor aggressiveness. Since hypoxia modulates the activity of BK channels in many tissues, we hypothesized that a hypoxia-induced modulation of these channels may contribute to the hypoxia-induced GBM aggressiveness. In U87-MG cells, hypoxia induced a functional upregulation of BK channel activity, without interfering with their plasma membrane expression. Wound healing and transwell migration assays showed that hypoxia increased the migratory ability of U87-MG cells, an effect that could be prevented by BK channel inhibition. Toxicological experiments showed that hypoxia was able to induce chemoresistance to cisplatin in U87-MG cells and that the inhibition of BK channels prevented the hypoxia-induced chemoresistance. Clonogenic assays showed that BK channels are also used to increase the clonogenic ability of U87-MG GBM cells in presence, but not in absence, of cisplatin. BK channels were also found to be essential for the hypoxia-induced de-differentiation of GBM cells. Finally, using immunohistochemical analysis, we highlighted the presence of BK channels in hypoxic areas of human GBM tissues, suggesting that our findings may have physiopathological relevance in vivo. In conclusion, our data show that BK channels promote several aspects of the aggressive potential of GBM cells induced by hypoxia, such as migration and chemoresistance to cisplatin, suggesting it as a potential therapeutic target in the treatment of GBM.
Collapse
Affiliation(s)
- Paolo Rosa
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome "Sapienza", Polo Pontino, Latina, Italy
| | - Luigi Catacuzzeno
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Luigi Sforna
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Giorgio Mangino
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome "Sapienza", Polo Pontino, Latina, Italy
| | - Silvia Carlomagno
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome "Sapienza", Polo Pontino, Latina, Italy
| | - Gabriella Mincione
- Department of Medical, Oral and Biotechnological Sciences, University "G. d'Annunzio" Chieti-Pescara, Italy
| | - Vincenzo Petrozza
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome "Sapienza", Polo Pontino, Latina, Italy.,Istituto Chirurgico Ortopedico Traumatologico, ICOT, Latina, Italy
| | - Giuseppe Ragona
- Istituto Chirurgico Ortopedico Traumatologico, ICOT, Latina, Italy.,Department of Experimental Medicine, University of Rome "Sapienza", Rome, Italy
| | - Fabio Franciolini
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Antonella Calogero
- Department of Medical-Surgical Sciences and Biotechnologies, University of Rome "Sapienza", Polo Pontino, Latina, Italy.,Istituto Chirurgico Ortopedico Traumatologico, ICOT, Latina, Italy
| |
Collapse
|
13
|
Chen Y, Kuang D, Zhao X, Chen D, Wang X, Yang Q, Wan J, Zhu Y, Wang Y, Zhang S, Wang Y, Tang Q, Masuzawa M, Wang G, Duan Y. miR-497-5p inhibits cell proliferation and invasion by targeting KCa3.1 in angiosarcoma. Oncotarget 2018; 7:58148-58161. [PMID: 27531900 PMCID: PMC5295420 DOI: 10.18632/oncotarget.11252] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 07/26/2016] [Indexed: 11/25/2022] Open
Abstract
Angiosarcoma is a rare malignant mesenchymal tumor with poor prognosis. We aimed to identify malignancy-associated miRNAs and their target genes, and explore biological functions of miRNA and its target in angiosarcoma. By miRNA microarrays and reverse transcription polymerase chain reaction, we identified 1 up-regulated miRNA (miR-222-3p) and 3 down-regulated miRNAs (miR-497-5p, miR-378-3p and miR-483-5p) in human angiosarcomas compared with human capillary hemangiomas. The intermediate-conductance calcium activated potassium channel KCa3.1 was one of the putative target genes of miR-497-5p, and marked up-regulation of KCa3.1 was detected in angiosarcoma biopsy specimens by immunohistochemistry. The inverse correlation of miR-497-5p and KCa3.1 also was observed in the ISO-HAS angiosarcoma cell line at the mRNA and protein levels. The direct targeting of KCa3.1 by miR-497-5p was evidenced by reduced luciferase activity due to complementary binding of miR-497-5p to KCa3.1 mRNA 3′ untranslated region. For the functional role of miR-497-5p/KCa3.1 pair, we showed that application of TRAM-34, a specific KCa3.1 channel blocker, or transfection of ISO-HAS cells with KCa3.1 siRNA or miR-497-5p mimics inhibited cell proliferation, cell cycle progression, and invasion by down-regulating cell-cycle related proteins including cyclin D1, surviving and P53 and down-regulating matrix metallopeptidase 9. In an in vivo angiosarcoma xenograft model, TRAM-34 or miR-497-5p mimics both inhibited tumor growth. In conclusion, the tumor suppressor miR-497-5p down-regulates KCa3.1 expression and contributes to the inhibition of angiosarcoma malignancy development. The miR-497-5p or KCa3.1 might be potential new targets for angiosarcoma treatment.
Collapse
Affiliation(s)
- Yaobing Chen
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Dong Kuang
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xia Zhao
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Dong Chen
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Xiaoyan Wang
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Qin Yang
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Jie Wan
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yuanli Zhu
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yu Wang
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Shiying Zhang
- Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Ying Wang
- Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Qiang Tang
- Department of Pharmacology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Mikio Masuzawa
- Department of Regulation Biochemistry, Kitasato University School of Allied Health Sciences, Minamiku, Sagamihara Kanagawa, 252-0329, Japan
| | - Guoping Wang
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| | - Yaqi Duan
- Institute of Pathology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China.,Department of Pathology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China
| |
Collapse
|
14
|
Reactive Astrocytes in Glioblastoma Multiforme. Mol Neurobiol 2018; 55:6927-6938. [PMID: 29363044 DOI: 10.1007/s12035-018-0880-8] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Accepted: 01/07/2018] [Indexed: 12/17/2022]
Abstract
Despite the multidisciplinary integration in the therapeutic management of glioblastoma multiforme (GBM), the prognosis of GBM patients is poor. There is growing recognition that the cells in the tumor microenvironment play a vital role in regulating the progression of glioma. Astrocytes are an important component of the blood-brain barrier (BBB) as well as the tripartite synapse neural network to promote bidirectional communication with neurons under physiological conditions. Emerging evidence shows that tumor-associated reactive astrocytes interact with glioma cells and facilitate the progression, aggression, and survival of tumors by releasing different cytokines. Communication between reactive astrocytes and glioma cells is further promoted through ion channels and ion transporters, which augment the migratory capacity and invasiveness of tumor cells by modifying H+ and Ca2+ concentrations and stimulating volume changes in the cell. This in part contributes to the loss of epithelial polarization, initiating epithelial-mesenchymal transition. Therefore, this review will summarize the recent findings on the role of reactive astrocytes in the progression of GBM and in the development of treatment-resistant glioma. In addition, the involvement of ion channels and transporters in bridging the interactions between tumor cells and astrocytes and their potential as new therapeutic anti-tumor targets will be discussed.
Collapse
|
15
|
Sforna L, Megaro A, Pessia M, Franciolini F, Catacuzzeno L. Structure, Gating and Basic Functions of the Ca2+-activated K Channel of Intermediate Conductance. Curr Neuropharmacol 2018; 16:608-617. [PMID: 28875832 PMCID: PMC5997868 DOI: 10.2174/1570159x15666170830122402] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Revised: 07/21/2017] [Accepted: 07/22/2017] [Indexed: 01/04/2023] Open
Abstract
BACKGROUND The KCa3.1 channel is the intermediate-conductance member of the Ca2+- activated K channel superfamily. It is widely expressed in excitable and non-excitable cells, where it plays a major role in a number of cell functions. This paper aims at illustrating the main structural, biophysical and modulatory properties of the KCa3.1 channel, and providing an account of experimental data on its role in volume regulation and Ca2+ signals. METHODS Research and online content related to the structure, structure/function relationship, and physiological role of the KCa3.1 channel are reviewed. RESULTS Expressed in excitable and non-excitable cells, the KCa3.1 channel is voltage independent, its opening being exclusively gated by the binding of intracellular Ca2+ to calmodulin, a Ca2+- binding protein constitutively associated with the C-terminus of each KCa3.1 channel α subunit. The KCa3.1 channel activates upon high affinity Ca2+ binding, and in highly coordinated fashion giving steep Hill functions and relatively low EC50 values (100-350 nM). This high Ca2+ sensitivity is physiologically modulated by closely associated kinases and phosphatases. The KCa3.1 channel is normally activated by global Ca2+ signals as resulting from Ca2+ released from intracellular stores, or by the refilling influx through store operated Ca2+ channels, but cases of strict functional coupling with Ca2+-selective channels are also found. KCa3.1 channels are highly expressed in many types of cells, where they play major roles in cell migration and death. The control of these complex cellular processes is achieved by KCa3.1 channel regulation of the driving force for Ca2+ entry from the extracellular medium, and by mediating the K+ efflux required for cell volume control. CONCLUSION Much work remains to be done to fully understand the structure/function relationship of the KCa3.1 channels. Hopefully, this effort will provide the basis for a beneficial modulation of channel activity under pathological conditions.
Collapse
Affiliation(s)
| | | | | | - Fabio Franciolini
- Address correspondence to these authors at the Department of Chemistry, Biology and Biotechnology, University of Perugia, Via Pascoli, 8-06123, Perugia; Tel: 39.075.585.5751; E-mails: and
| | - Luigi Catacuzzeno
- Address correspondence to these authors at the Department of Chemistry, Biology and Biotechnology, University of Perugia, Via Pascoli, 8-06123, Perugia; Tel: 39.075.585.5751; E-mails: and
| |
Collapse
|
16
|
D'Alessandro G, Grimaldi A, Chece G, Porzia A, Esposito V, Santoro A, Salvati M, Mainiero F, Ragozzino D, Di Angelantonio S, Wulff H, Catalano M, Limatola C. KCa3.1 channel inhibition sensitizes malignant gliomas to temozolomide treatment. Oncotarget 2017; 7:30781-96. [PMID: 27096953 PMCID: PMC5058717 DOI: 10.18632/oncotarget.8761] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 03/31/2016] [Indexed: 01/19/2023] Open
Abstract
Malignant gliomas are among the most frequent and aggressive cerebral tumors, characterized by high proliferative and invasive indexes. Standard therapy for patients, after surgery and radiotherapy, consists of temozolomide (TMZ), a methylating agent that blocks tumor cell proliferation. Currently, there are no therapies aimed at reducing tumor cell invasion. Ion channels are candidate molecular targets involved in glioma cell migration and infiltration into the brain parenchyma. In this paper we demonstrate that: i) blockade of the calcium-activated potassium channel KCa3.1 with TRAM-34 has co-adjuvant effects with TMZ, reducing GL261 glioma cell migration, invasion and colony forming activity, increasing apoptosis, and forcing cells to pass the G2/M cell cycle phase, likely through cdc2 de-phosphorylation; ii) KCa3.1 silencing potentiates the inhibitory effect of TMZ on glioma cell viability; iii) the combination of TMZ/TRAM-34 attenuates the toxic effects of glioma conditioned medium on neuronal cultures, through a microglia dependent mechanism since the effect is abolished by clodronate-induced microglia killing; iv) TMZ/TRAM-34 co-treatment increases the number of apoptotic tumor cells, and the mean survival time in a syngeneic mouse glioma model (C57BL6 mice implanted with GL261 cells); v) TMZ/TRAM-34 co-treatment reduces cell viability of GBM cells and cancer stem cells (CSC) freshly isolated from patients.Taken together, these data suggest a new therapeutic approach for malignant glioma, targeting both glioma cell proliferating and migration, and demonstrate that TMZ/TRAM-34 co-treatment affects both glioma cells and infiltrating microglia, resulting in an overall reduction of tumor cell progression.
Collapse
Affiliation(s)
- Giuseppina D'Alessandro
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Alfonso Grimaldi
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Giuseppina Chece
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | - Alessandra Porzia
- Department of Molecular Medicine, Sapienza University of Rome, Rome, Italy
| | - Vincenzo Esposito
- IRCCS Neuromed, Pozzilli, Italy.,Department of Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy
| | - Antonio Santoro
- Department of Neurology and Psychiatry, Sapienza University of Rome, Rome, Italy
| | - Maurizio Salvati
- Department of Science and Medical Surgical Biotechnology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Fabrizio Mainiero
- Department of Experimental Medicine, Sapienza University of Rome, Rome, Italy
| | - Davide Ragozzino
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Silvia Di Angelantonio
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,Center for Life Nanoscience Istituto Italiano di Tecnologia@Sapienza, Rome, Italy
| | - Heike Wulff
- Department of Pharmacology, University of California Davis, Davis, USA
| | - Myriam Catalano
- Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy.,IRCCS Neuromed, Pozzilli, Italy
| | - Cristina Limatola
- IRCCS Neuromed, Pozzilli, Italy.,Pasteur Institute Rome-Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| |
Collapse
|
17
|
Rosa P, Sforna L, Carlomagno S, Mangino G, Miscusi M, Pessia M, Franciolini F, Calogero A, Catacuzzeno L. Overexpression of Large-Conductance Calcium-Activated Potassium Channels in Human Glioblastoma Stem-Like Cells and Their Role in Cell Migration. J Cell Physiol 2017; 232:2478-2488. [PMID: 27606467 DOI: 10.1002/jcp.25592] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2016] [Accepted: 09/07/2016] [Indexed: 01/24/2023]
Abstract
Glioblastomas (GBMs) are brain tumors characterized by diffuse invasion of cancer cells into the healthy brain parenchyma, and establishment of secondary foci. GBM cells abundantly express large-conductance, calcium-activated potassium (BK) channels that are thought to promote cell invasion. Recent evidence suggests that the GBM high invasive potential mainly originates from a pool of stem-like cells, but the expression and function of BK channels in this cell subpopulation have not been studied. We investigated the expression of BK channels in GBM stem-like cells using electrophysiological and immunochemical techniques, and assessed their involvement in the migratory process of this important cell subpopulation. In U87-MG cells, BK channel expression and function were markedly upregulated by growth conditions that enriched the culture in GBM stem-like cells (U87-NS). Cytofluorimetric analysis further confirmed the appearance of a cell subpopulation that co-expressed high levels of BK channels and CD133, as well as other stem cell markers. A similar association was also found in cells derived from freshly resected GBM biopsies. Finally, transwell migration tests showed that U87-NS cells migration was much more sensitive to BK channel block than U87-MG cells. Our data show that BK channels are highly expressed in GBM stem-like cells, and participate to their high migratory activity. J. Cell. Physiol. 232: 2478-2488, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Paolo Rosa
- Department of Medico-Surgical Sciences and Biotechnologies, "La Sapienza" University, Latina, Italy
| | - Luigi Sforna
- Department of Chemistry Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Silvia Carlomagno
- Department of Medico-Surgical Sciences and Biotechnologies, "La Sapienza" University, Latina, Italy
| | - Giorgio Mangino
- Department of Medico-Surgical Sciences and Biotechnologies, "La Sapienza" University, Latina, Italy
| | - Massimo Miscusi
- Department of Medico-Surgical Sciences and Biotechnologies, "La Sapienza" University, Latina, Italy
| | - Mauro Pessia
- Department of Experimental Medicine, University of Perugia, Perugia, Italy.,Department of Physiology and Biochemistry, University of Malta, Msida, Malta
| | - Fabio Franciolini
- Department of Chemistry Biology and Biotechnology, University of Perugia, Perugia, Italy
| | - Antonella Calogero
- Department of Medico-Surgical Sciences and Biotechnologies, "La Sapienza" University, Latina, Italy
| | - Luigi Catacuzzeno
- Department of Chemistry Biology and Biotechnology, University of Perugia, Perugia, Italy
| |
Collapse
|
18
|
Sforna L, Cenciarini M, Belia S, Michelucci A, Pessia M, Franciolini F, Catacuzzeno L. Hypoxia Modulates the Swelling-Activated Cl Current in Human Glioblastoma Cells: Role in Volume Regulation and Cell Survival. J Cell Physiol 2016; 232:91-100. [PMID: 27028592 DOI: 10.1002/jcp.25393] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Accepted: 03/25/2016] [Indexed: 12/18/2022]
Abstract
The malignancy of glioblastoma multiforme (GBM), the most common human brain tumor, correlates with the presence of hypoxic areas, but the underlying mechanisms are unclear. GBM cells express abundant Cl channels whose activity supports cell volume and membrane potential changes, ultimately leading to cell proliferation, migration, and escaping death. In non-tumor tissues Cl channels are modulated by hypoxia, which prompted us to verify whether hypoxia would also modulate Cl channels in GBM cells. Our results show that in GBM cell lines, acute application of a hypoxic solution activates a Cl current displaying the biophysical and pharmacological features of the swelling-activated Cl current (ICl,swell ). We also found that acute hypoxia increased the cell volume by about 20%, and a 30% hypertonic solution partially inhibited the hypoxia-activated Cl current, suggesting that cell swelling and the activation of the Cl current are sequential events. Notably, the hypoxia-induced cell swelling was followed by a regulatory volume decrease (RVD) mediated mainly by ICl,swell . Since, a hypoxia-induced prolonged cell swelling is usually regarded as a death insult, we hypothesized that the hypoxia-activated Cl current could limit cell swelling and prevent necrotic death of GBM cells under hypoxic conditions. In accordance, we found that the ICl,swell inhibitor DCPIB hampered the RVD process, and more importantly it sensibly increased the hypoxia-induced necrotic death in these cells. Taken together, these results suggest that Cl channels are strongly involved in the survival of GBM cells in a hypoxic environment, and may thus represent a new therapeutic target for this malignant tumor. J. Cell. Physiol. 232: 91-100, 2017. © 2016 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Luigi Sforna
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Italy.,Department of Experimental Medicine, University of Perugia, Italy
| | - Marta Cenciarini
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Italy
| | - Silvia Belia
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Italy
| | - Antonio Michelucci
- Department of Neuroscience, Imaging and Clinical Sciences, University of Chieti 'G. d'Annunzio', Italy
| | - Mauro Pessia
- Department of Experimental Medicine, University of Perugia, Italy
| | - Fabio Franciolini
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Italy.
| | - Luigi Catacuzzeno
- Department of Chemistry, Biology and Biotechnology, University of Perugia, Italy.
| |
Collapse
|
19
|
Zhang P, Yang X, Yin Q, Yi J, Shen W, Zhao L, Zhu Z, Liu J. Inhibition of SK4 Potassium Channels Suppresses Cell Proliferation, Migration and the Epithelial-Mesenchymal Transition in Triple-Negative Breast Cancer Cells. PLoS One 2016; 11:e0154471. [PMID: 27124117 PMCID: PMC4849628 DOI: 10.1371/journal.pone.0154471] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 04/14/2016] [Indexed: 11/21/2022] Open
Abstract
Treatments for triple-negative breast cancer (TNBC) are limited; intermediate-conductance calcium-activated potassium (SK4) channels are closely involved in tumor progression, but little is known about these channels in TNBC. We aimed to investigate whether SK4 channels affect TNBC. First, by immunohistochemistry (IHC) and western blotting (WB), increased SK4 protein expression in breast tumor tissues was detected relative to that in non-tumor breast tissues, but there was no apparent expression difference between various subtypes of breast cancer (p>0.05). Next, functional SK4 channels were detected in the TNBC cell line MDA-MB-231 using WB, real-time PCR, immunofluorescence and patch-clamp recording. By employing SK4 specific siRNAs and blockers, including TRAM-34 and clotrimazole, in combination with an MTT assay, a colony-formation assay, flow cytometry and a cell motility assay, we found that the suppression of SK4 channels significantly inhibited cell proliferation and migration and promoted apoptosis in MDA-MB-231 cells (p<0.05). Further investigation revealed that treatment with epidermal growth factor (EGF)/basic fibroblast growth factor (bFGF) caused MDA-MB-231 cells to undergo the epithelial-mesenchymal transition (EMT) and to show increased SK4 mRNA expression. In addition, the down-regulation of SK4 expression inhibited the EMT markers Vimentin and Snail1. Collectively, our findings suggest that SK4 channels are expressed in TNBC and are involved in the proliferation, apoptosis, migration and EMT processes of TNBC cells.
Collapse
Affiliation(s)
- Panshi Zhang
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaowei Yang
- Department of General Surgery, the First Affiliated Hospital, Anhui Medical University, Hefei, China
| | - Qian Yin
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jilin Yi
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Wenzhuang Shen
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Lu Zhao
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Zhi Zhu
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jinwen Liu
- Department of Thyroid and Breast Surgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
- * E-mail:
| |
Collapse
|
20
|
Lanciotti A, Brignone MS, Visentin S, De Nuccio C, Catacuzzeno L, Mallozzi C, Petrini S, Caramia M, Veroni C, Minnone G, Bernardo A, Franciolini F, Pessia M, Bertini E, Petrucci TC, Ambrosini E. Megalencephalic leukoencephalopathy with subcortical cysts protein-1 regulates epidermal growth factor receptor signaling in astrocytes. Hum Mol Genet 2016; 25:1543-58. [DOI: 10.1093/hmg/ddw032] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Accepted: 02/03/2016] [Indexed: 01/13/2023] Open
|
21
|
Stegen B, Butz L, Klumpp L, Zips D, Dittmann K, Ruth P, Huber SM. Ca2+-Activated IK K+ Channel Blockade Radiosensitizes Glioblastoma Cells. Mol Cancer Res 2015; 13:1283-95. [PMID: 26041939 DOI: 10.1158/1541-7786.mcr-15-0075] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 05/22/2015] [Indexed: 11/16/2022]
Abstract
UNLABELLED Ca(2+)-activated K(+) channels, such as BK and IK channels, have been proposed to fulfill pivotal functions in neoplastic transformation, malignant progression, and brain infiltration of glioblastoma cells. Here, the ionizing radiation (IR) effect of IK K(+) channel targeting was tested in human glioblastoma cells. IK channels were inhibited pharmacologically by TRAM-34 or genetically by knockdown, cells were irradiated with 6 MV photons and IK channel activity, Ca(2+) signaling, cell cycling, residual double-strand breaks, and clonogenic survival were determined. In addition, the radiosensitizing effect of TRAM-34 was analyzed in vivo in ectopic tumors. Moreover, The Cancer Genome Atlas (TCGA) was queried to expose the dependence of IK mRNA abundance on overall survival (OS) of patients with glioma. Results indicate that radiation increased the activity of IK channels, modified Ca(2+) signaling, and induced a G2-M cell-cycle arrest. TRAM-34 decreased the IR-induced accumulation in G2-M arrest and increased the number of γH2AX foci post-IR, suggesting that TRAM-34 mediated an increase of residual DNA double-strand breaks. Mechanistically, IK knockdown abolished the TRAM-34 effects indicating the IK specificity of TRAM-34. Finally, TRAM-34 radiosensitized ectopic glioblastoma in vivo and high IK mRNA abundance associated with shorter patient OS in low-grade glioma and glioblastoma. IMPLICATIONS Together, these data support a cell-cycle regulatory function for IK K(+) channels, and combined therapy using IK channel targeting and radiation is a new strategy for anti-glioblastoma therapy.
Collapse
Affiliation(s)
- Benjamin Stegen
- Department of Radiation Oncology, University of Tübingen, Tübingen, Germany
| | - Lena Butz
- Department of Radiation Oncology, University of Tübingen, Tübingen, Germany. Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Lukas Klumpp
- Department of Radiation Oncology, University of Tübingen, Tübingen, Germany. Dr. Margarete Fischer-Bosch-Institute of Clinical Pharmacology, Stuttgart, Germany
| | - Daniel Zips
- Department of Radiation Oncology, University of Tübingen, Tübingen, Germany
| | - Klaus Dittmann
- Division of Radiobiology and Molecular Environmental Research, Department of Radiation Oncology, University of Tübingen, Tübingen, Germany
| | - Peter Ruth
- Department of Pharmacology, Toxicology and Clinical Pharmacy, Institute of Pharmacy, University of Tübingen, Tübingen, Germany
| | - Stephan M Huber
- Department of Radiation Oncology, University of Tübingen, Tübingen, Germany.
| |
Collapse
|
22
|
Catacuzzeno L, Caramia M, Sforna L, Belia S, Guglielmi L, D'Adamo MC, Pessia M, Franciolini F. Reconciling the discrepancies on the involvement of large-conductance Ca(2+)-activated K channels in glioblastoma cell migration. Front Cell Neurosci 2015; 9:152. [PMID: 25941475 PMCID: PMC4403502 DOI: 10.3389/fncel.2015.00152] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 04/02/2015] [Indexed: 02/04/2023] Open
Abstract
Glioblastoma (GBM) is the most common and aggressive primary brain tumor, and is notable for spreading so effectively through the brain parenchyma to make complete surgical resection virtually impossible, and prospect of life dismal. Several ion channels have been involved in GBM migration and invasion, due to their critical role in supporting volume changes and Ca(2+) influx occuring during the process. The large-conductance, Ca(2+)-activated K (BK) channels, markedly overexpressed in biopsies of patients with GBMs and in GBM cell lines, have attracted much interest and have been suggested to play a central role in cell migration and invasion as candidate channels for providing the ion efflux and consequent water extrusion that allow cell shrinkage during migration. Available experimental data on the role of BK channel in migration and invasion are not consistent though. While BK channels block typically resulted in inhibition of cell migration or in no effect, their activation would either enhance or inhibit the process. This short review reexamines the relevant available data on the topic, and presents a unifying paradigm capable of reconciling present discrepancies. According to this paradigm, BK channels would not contribute to migration under conditions where the [Ca(2+)] i is too low for their activation. They will instead positively contribute to migration for intermediate [Ca(2+)] i , insufficient as such to activate BK channels, but capable of predisposing them to cyclic activation following oscillatory [Ca(2+)] i increases. Finally, steadily active BK channels because of prolonged high [Ca(2+)] i would inhibit migration as their steady activity would be unsuitable to match the cyclic cell volume changes needed for proper cell migration.
Collapse
Affiliation(s)
- Luigi Catacuzzeno
- Dipartimento di Chimica, Biologia e Biotecnologie, Universita' di Perugia Perugia, Italy
| | - Martino Caramia
- Dipartimento di Chimica, Biologia e Biotecnologie, Universita' di Perugia Perugia, Italy
| | - Luigi Sforna
- Dipartimento di Chimica, Biologia e Biotecnologie, Universita' di Perugia Perugia, Italy
| | - Silvia Belia
- Dipartimento di Chimica, Biologia e Biotecnologie, Universita' di Perugia Perugia, Italy
| | - Luca Guglielmi
- Dipartimento di Medicina Sperimentale, Scuola di Medicina e Chirurgia, Universita' di Perugia Perugia, Italy
| | - Maria Cristina D'Adamo
- Dipartimento di Medicina Sperimentale, Scuola di Medicina e Chirurgia, Universita' di Perugia Perugia, Italy
| | - Mauro Pessia
- Dipartimento di Medicina Sperimentale, Scuola di Medicina e Chirurgia, Universita' di Perugia Perugia, Italy
| | - Fabio Franciolini
- Dipartimento di Chimica, Biologia e Biotecnologie, Universita' di Perugia Perugia, Italy
| |
Collapse
|
23
|
Ferreira R, Wong R, Schlichter LC. KCa3.1/IK1 Channel Regulation by cGMP-Dependent Protein Kinase (PKG) via Reactive Oxygen Species and CaMKII in Microglia: An Immune Modulating Feedback System? Front Immunol 2015; 6:153. [PMID: 25904916 PMCID: PMC4389654 DOI: 10.3389/fimmu.2015.00153] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Accepted: 03/23/2015] [Indexed: 01/09/2023] Open
Abstract
The intermediate conductance Ca2+-activated K+ channel, KCa3.1 (IK1/SK4/KCNN4) is widely expressed in the innate and adaptive immune system. KCa3.1 contributes to proliferation of activated T lymphocytes, and in CNS-resident microglia, it contributes to Ca2+ signaling, migration, and production of pro-inflammatory mediators (e.g., reactive oxygen species, ROS). KCa3.1 is under investigation as a therapeutic target for CNS disorders that involve microglial activation and T cells. However, KCa3.1 is post-translationally regulated, and this will determine when and how much it can contribute to cell functions. We previously found that KCa3.1 trafficking and gating require calmodulin (CaM) binding, and this is inhibited by cAMP kinase (PKA) acting at a single phosphorylation site. The same site is potentially phosphorylated by cGMP kinase (PKG), and in some cells, PKG can increase Ca2+, CaM activation, and ROS. Here, we addressed KCa3.1 regulation through PKG-dependent pathways in primary rat microglia and the MLS-9 microglia cell line, using perforated-patch recordings to preserve intracellular signaling. Elevating cGMP increased both the KCa3.1 current and intracellular ROS production, and both were prevented by the selective PKG inhibitor, KT5823. The cGMP/PKG-evoked increase in KCa3.1 current in intact MLS-9 microglia was mediated by ROS, mimicked by applying hydrogen peroxide (H2O2), inhibited by a ROS scavenger (MGP), and prevented by a selective CaMKII inhibitor (mAIP). Similar results were seen in alternative-activated primary rat microglia; their KCa3.1 current required PKG, ROS, and CaMKII, and they had increased ROS production that required KCa3.1 activity. The increase in current apparently did not result from direct effects on the channel open probability (Po) or Ca2+ dependence because, in inside-out patches from transfected HEK293 cells, single-channel activity was not affected by cGMP, PKG, H2O2 at normal or elevated intracellular Ca2+. The regulation pathway we have identified in intact microglia and MLS-9 cells is expected to have broad implications because KCa3.1 plays important roles in numerous cells and tissues.
Collapse
Affiliation(s)
- Roger Ferreira
- Genetics and Development Division, Toronto Western Research Institute, University Health Network , Toronto, ON , Canada ; Department of Physiology, University of Toronto , Toronto, ON , Canada
| | - Raymond Wong
- Genetics and Development Division, Toronto Western Research Institute, University Health Network , Toronto, ON , Canada ; Department of Physiology, University of Toronto , Toronto, ON , Canada
| | - Lyanne C Schlichter
- Genetics and Development Division, Toronto Western Research Institute, University Health Network , Toronto, ON , Canada ; Department of Physiology, University of Toronto , Toronto, ON , Canada
| |
Collapse
|
24
|
Abstract
There is an urgent need to identify novel interventions for mitigating the progression of diabetic nephropathy. Diabetic nephropathy is characterized by progressive renal fibrosis, in which tubulointerstitial fibrosis has been shown to be the final common pathway of all forms of chronic progressive renal disease, including diabetic nephropathy. Therefore targeting the possible mechanisms that drive this process may provide novel therapeutics which allow the prevention and potentially retardation of the functional decline in diabetic nephropathy. Recently, the Ca2+-activated K+ channel KCa3.1 (KCa3.1) has been suggested as a potential therapeutic target for nephropathy, based on its ability to regulate Ca2+ entry into cells and modulate Ca2+-signalling processes. In the present review, we focus on the physiological role of KCa3.1 in those cells involved in the tubulointerstitial fibrosis, including proximal tubular cells, fibroblasts, inflammatory cells (T-cells and macrophages) and endothelial cells. Collectively these studies support further investigation into KCa3.1 as a therapeutic target in diabetic nephropathy.
Collapse
|
25
|
Chou CC, Lunn CA, Murgolo NJ. KCa3.1: target and marker for cancer, autoimmune disorder and vascular inflammation? Expert Rev Mol Diagn 2014; 8:179-87. [DOI: 10.1586/14737159.8.2.179] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
26
|
Catacuzzeno L, Sforna L, D'Adamo MC, Pessia M, Franciolini F. A method to identify tissue cell subpopulations with distinct multi-molecular profiles from data on co-localization of two markers at a time: the case of sensory ganglia. J Neurosci Methods 2014; 224:88-95. [PMID: 24412313 DOI: 10.1016/j.jneumeth.2013.12.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2013] [Revised: 11/23/2013] [Accepted: 12/31/2013] [Indexed: 01/03/2023]
Abstract
BACKGROUND Most biological tissues are characterized by high morphological and functional cell heterogeneity. To investigate this heterogeneity at the molecular level, scientists have tried to associate specific sets of molecular markers (molecular profiles) to functionally distinct cell subpopulations, evaluating their expression using immunochemistry and in situ hybridization techniques. NEW METHOD We propose here a novel analysis that allows the estimation of the frequency of cells expressing distinct molecular profiles starting from data on the co-expression of two markers at a time. In order to facilitate the application of the proposed analysis, we developed and make available a user-friendly window-based software. RESULTS We successfully applied the analytical method to experimental data from adult rat sensory neurons. In a first application we subgrouped DRG neurons in 11 subpopulations on the basis of the co-expression of 6 molecular markers (the TRPs type V1, A1, and M8 and the trks type A, B, and C). In a second application we found that while rat DRG have significant frequencies of peptidergic/IB4-negative and non-peptidergic/IB4-positive nociceptors, rat TG neurons lack almost completely these two subpopulations. COMPARISON WITH EXISTING METHODS The analytical method here proposed overcomes the limitations of the presently available experimental techniques, most of which can assess the co-expression of only few molecular markers at a time. CONCLUSIONS This new method will allow a better understanding of the molecular and cellular heterogeneity of tissues in normal and pathological conditions.
Collapse
Affiliation(s)
- Lugi Catacuzzeno
- Dipartimento di Chimica, Biologia e Biotecnologie, Universita' di Perugia, via Pascoli 1, Perugia, Italy.
| | - Luigi Sforna
- Dipartimento di Chimica, Biologia e Biotecnologie, Universita' di Perugia, via Pascoli 1, Perugia, Italy
| | - Maria Cristina D'Adamo
- Dipartimento di Medicina Sperimentale, Sezione di Fisiologia e Biochimica, Universita' di Perugia, Perugia, Italy
| | - Mauro Pessia
- Dipartimento di Medicina Sperimentale, Sezione di Fisiologia e Biochimica, Universita' di Perugia, Perugia, Italy
| | - Fabio Franciolini
- Dipartimento di Chimica, Biologia e Biotecnologie, Universita' di Perugia, via Pascoli 1, Perugia, Italy
| |
Collapse
|
27
|
Catacuzzeno L, Michelucci A, Sforna L, Aiello F, Sciaccaluga M, Fioretti B, Castigli E, Franciolini F. Identification of key signaling molecules involved in the activation of the swelling-activated chloride current in human glioblastoma cells. J Membr Biol 2013; 247:45-55. [PMID: 24240542 DOI: 10.1007/s00232-013-9609-9] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Accepted: 10/14/2013] [Indexed: 12/17/2022]
Abstract
The swelling-activated chloride current (I Cl,Vol) is abundantly expressed in glioblastoma (GBM) cells, where it controls cell volume and invasive migration. The transduction pathway mediating I Cl,Vol activation in GBM cells is, however, poorly understood. By means of pharmacological and electrophysiological approaches, on GL-15 human GBM cells we found that I Cl,Vol activation by hypotonic swelling required the activity of a U73122-sensitive phospholipase C (PLC). I Cl,Vol activation could also be induced by the membrane-permeable diacylglycerol (DAG) analog OAG. In contrast, neither calcium (Ca(2+)) chelation by BAPTA-AM nor changes in PKC activity were able to affect I Cl,Vol activation by hypotonic swelling. We further found that R59022, an inhibitor of diacylglycerol kinase (DGK), reverted I Cl,Vol activation, suggesting the involvement of phosphatidic acid. In addition, I Cl,Vol activation required the activity of a EHT1864-sensitive Rac1 small GTPase and the resulting actin polymerization, as I Cl,Vol activation was prevented by cytochalasin B. We finally show that I Cl,Vol can be activated by the promigratory fetal calf serum in a PLC- and DGK-dependent manner. This observation is potentially relevant because blood serum can likely come in contact with glioblastoma cells in vivo as a result of the tumor-related partial breakdown of the blood-brain barrier. Given the relevance of I Cl,Vol in GBM cell volume regulation and invasiveness, the several key signaling molecules found in this study to be involved in the activation of the I Cl,Vol may represent potential therapeutic targets against this lethal cancer.
Collapse
Affiliation(s)
- Luigi Catacuzzeno
- Dipartimento di Biologia Cellulare e Ambientale, Universita' di Perugia, Via Pascoli 1, 06123, Perugia, Italy,
| | | | | | | | | | | | | | | |
Collapse
|
28
|
D'Alessandro G, Catalano M, Sciaccaluga M, Chece G, Cipriani R, Rosito M, Grimaldi A, Lauro C, Cantore G, Santoro A, Fioretti B, Franciolini F, Wulff H, Limatola C. KCa3.1 channels are involved in the infiltrative behavior of glioblastoma in vivo. Cell Death Dis 2013; 4:e773. [PMID: 23949222 PMCID: PMC3763441 DOI: 10.1038/cddis.2013.279] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 06/25/2013] [Accepted: 07/02/2013] [Indexed: 01/03/2023]
Abstract
Glioblastoma multiforme (GBM) is a diffuse brain tumor characterized by high infiltration in the brain parenchyma rendering the tumor difficult to eradicate by neurosurgery. Efforts to identify molecular targets involved in the invasive behavior of GBM suggested ion channel inhibition as a promising therapeutic approach. To determine if the Ca(2+)-dependent K(+) channel KCa3.1 could represent a key element for GBM brain infiltration, human GL-15 cells were xenografted into the brain of SCID mice that were then treated with the specific KCa3.1 blocker TRAM-34 (1-((2-chlorophenyl) (diphenyl)methyl)-1H-pyrazole). After 5 weeks of treatment, immunofluorescence analyses of cerebral slices revealed reduced tumor infiltration and astrogliosis surrounding the tumor, compared with untreated mice. Significant reduction of tumor infiltration was also observed in the brain of mice transplanted with KCa3.1-silenced GL-15 cells, indicating a direct effect of TRAM-34 on GBM-expressed KCa3.1 channels. As KCa3.1 channels are also expressed on microglia, we investigated the effects of TRAM-34 on microglia activation in GL-15 transplanted mice and found a reduction of CD68 staining in treated mice. Similar results were observed in vitro where TRAM-34 reduced both phagocytosis and chemotactic activity of primary microglia exposed to GBM-conditioned medium. Taken together, these results indicate that KCa3.1 activity has an important role in GBM invasiveness in vivo and that its inhibition directly affects glioma cell migration and reduces astrocytosis and microglia activation in response to tumor-released factors. KCa3.1 channel inhibition therefore constitutes a potential novel therapeutic approach to reduce GBM spreading into the surrounding tissue.
Collapse
Affiliation(s)
- G D'Alessandro
- Institute Pasteur, Cenci Bolognetti Foundation, Department of Physiology and Pharmacology, Sapienza University of Rome, Rome, Italy
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
29
|
Yu ZH, Xu JR, Wang YX, Xu GN, Xu ZP, Yang K, Wu DZ, Cui YY, Chen HZ. Targeted inhibition of KCa3.1 channel attenuates airway inflammation and remodeling in allergic asthma. Am J Respir Cell Mol Biol 2013; 48:685-93. [PMID: 23492185 DOI: 10.1165/rcmb.2012-0236oc] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
KCa3.1 has been suggested to be involved in regulating cell activation, proliferation, and migration in multiple cell types, including airway inflammatory and structural cells. However, the contributions of KCa3.1 to airway inflammation and remodeling and subsequent airway hyperresponsiveness (AHR) in allergic asthma remain to be explored. The main purpose of this study was to elucidate the roles of KCa3.1 and the potential therapeutic value of KCa3.1 blockers in chronic allergic asthma. Using real-time PCR, Western blotting, or immunohistochemical analyses, we explored the precise role of KCa3.1 in the bronchi of allergic mice and asthmatic human bronchial smooth muscle cells (BSMCs). We found that KCa3.1 mRNA and protein expression were elevated in the bronchi of allergic mice, and double labeling revealed that up-regulation occurred primarily in airway smooth muscle cells. Triarylmethane (TRAM)-34, a KCa3.1 blocker, dose-dependently inhibited the generation and maintenance of the ovalbumin-induced airway inflammation associated with increased Th2-type cytokines and decreased Th1-type cytokine, as well as subepithelial extracellular matrix deposition, goblet-cell hyperplasia, and AHR in a murine model of asthma. Moreover, the pharmacological blockade and gene silencing of KCa3.1, which was evidently elevated after mitogen stimulation, suppressed asthmatic human BSMC proliferation and migration, and arrested the cell cycle at the G0/G1 phase. In addition, the KCa3.1 activator 1-ethylbenzimidazolinone-induced membrane hyperpolarization and intracellular calcium increase in asthmatic human BSMCs were attenuated by TRAM-34. We demonstrate for the first time an important role for KCa3.1 in the pathogenesis of airway inflammation and remodeling in allergic asthma, and we suggest that KCa3.1 blockers may represent a promising therapeutic strategy for asthma.
Collapse
Affiliation(s)
- Zhi-Hua Yu
- Department of Pharmacology, Institute of Medical Sciences, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Ruggieri P, Mangino G, Fioretti B, Catacuzzeno L, Puca R, Ponti D, Miscusi M, Franciolini F, Ragona G, Calogero A. The inhibition of KCa3.1 channels activity reduces cell motility in glioblastoma derived cancer stem cells. PLoS One 2012; 7:e47825. [PMID: 23110108 PMCID: PMC3478269 DOI: 10.1371/journal.pone.0047825] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Accepted: 09/17/2012] [Indexed: 02/04/2023] Open
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.
Collapse
Affiliation(s)
- Paola Ruggieri
- Department of Medical-surgical Sciences and Biotechnologies, University of Rome "Sapienza", Latina, Italy
| | - Giorgio Mangino
- Department of Medical-surgical Sciences and Biotechnologies, University of Rome "Sapienza", Latina, Italy
| | - Bernard Fioretti
- Department of Cellular and Environmental Biology, University of Perugia, Perugia, Italy
| | - Luigi Catacuzzeno
- Department of Cellular and Environmental Biology, University of Perugia, Perugia, Italy
| | - Rosa Puca
- Department of Medical-surgical Sciences and Biotechnologies, University of Rome "Sapienza", Latina, Italy
| | - Donatella Ponti
- Department of Medical-surgical Sciences and Biotechnologies, University of Rome "Sapienza", Latina, Italy
| | - Massimo Miscusi
- Department of Medical-surgical Sciences and Biotechnologies, University of Rome "Sapienza", Latina, Italy
| | - Fabio Franciolini
- Department of Cellular and Environmental Biology, University of Perugia, Perugia, Italy
| | - Giuseppe Ragona
- Department of Medical-surgical Sciences and Biotechnologies, University of Rome "Sapienza", Latina, Italy
| | - Antonella Calogero
- Department of Medical-surgical Sciences and Biotechnologies, University of Rome "Sapienza", Latina, Italy
- * E-mail:
| |
Collapse
|
31
|
McFerrin MB, Turner KL, Cuddapah VA, Sontheimer H. Differential role of IK and BK potassium channels as mediators of intrinsic and extrinsic apoptotic cell death. Am J Physiol Cell Physiol 2012; 303:C1070-8. [PMID: 22992678 DOI: 10.1152/ajpcell.00040.2012] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
An important event during apoptosis is regulated cell condensation known as apoptotic volume decrease (AVD). Ion channels have emerged as essential regulators of this process mediating the release of K(+) and Cl(-), which together with osmotically obliged water, results in the condensation of cell volume. Using a Grade IV human glioblastoma cell line, we examined the contribution of calcium-activated K(+) channels (K(Ca) channels) to AVD after the addition of either staurosporine (Stsp) or TNF-α-related apoptosis-inducing ligand (TRAIL) to activate the intrinsic or extrinsic pathway of apoptosis, respectively. We show that AVD can be inhibited in both pathways by high extracellular K(+) or the removal of calcium. However, BAPTA-AM was only able to inhibit Stsp-initiated AVD, whereas TRAIL-induced AVD was unaffected. Specific K(Ca) channel inhibitors revealed that Stsp-induced AVD was dependent on K(+) efflux through intermediate-conductance calcium-activated potassium (IK) channels, while TRAIL-induced AVD was mediated by large-conductance calcium-activated potassium (BK) channels. Fura-2 imaging demonstrated that Stsp induced a rapid and modest rise in calcium that was sustained over the course of AVD, while TRAIL produced no detectable rise in global intracellular calcium. Inhibition of IK channels with clotrimazole or 1-[(2-chlorophenyl) diphenylmethyl]-1H-pyrazole (TRAM-34) blocked downstream caspase-3 activation after Stsp addition, while paxilline, a specific BK channel inhibitor, had no effect. Treatment with ionomycin also induced an IK-dependent cell volume decrease. Together these results show that calcium is both necessary and sufficient to achieve volume decrease and that the two major pathways of apoptosis use unique calcium signaling to efflux K(+) through different K(Ca) channels.
Collapse
Affiliation(s)
- Michael B McFerrin
- Deptartment of Neurobiology and Center for Glial Biology in Medicine, Universtiy of Alabama at Birmingham, 1719 6th Ave. South, CIRC 410, Birmingham, AL, 35294, USA
| | | | | | | |
Collapse
|
32
|
Expression and Role of the Intermediate-Conductance Calcium-Activated Potassium Channel KCa3.1 in Glioblastoma. JOURNAL OF SIGNAL TRANSDUCTION 2012; 2012:421564. [PMID: 22675627 PMCID: PMC3362965 DOI: 10.1155/2012/421564] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2012] [Accepted: 03/15/2012] [Indexed: 12/29/2022]
Abstract
Glioblastomas are characterized by altered expression of several ion channels that have important consequences in cell functions associated with their aggressiveness, such as cell survival, proliferation, and migration. Data on the altered expression and function of the intermediate-conductance calcium-activated K (KCa3.1) channels in glioblastoma cells have only recently become available. This paper aims to (i) illustrate the main structural, biophysical, pharmacological, and modulatory properties of the KCa3.1 channel, (ii) provide a detailed account of data on the expression of this channel in glioblastoma cells, as compared to normal brain tissue, and (iii) critically discuss its major functional roles. Available data suggest that KCa3.1 channels (i) are highly expressed in glioblastoma cells but only scantly in the normal brain parenchima, (ii) play an important role in the control of glioblastoma cell migration. Altogether, these data suggest KCa3.1 channels as potential candidates for a targeted therapy against this tumor.
Collapse
|
33
|
Abstract
Ion channels are involved in a variety of tumors. In particular, potassium channels are expressed abnormally in many cancer types, where their pharmacologic manipulation impairs tumor progression. Since this group of molecules has been successfully targeted for decades in other therapeutic areas, there is a significant body of knowledge on the pharmacology of potassium channels. Several groups of potassium channels with defined molecular identities have been proposed as candidates for therapeutic intervention. The strategies put forward range from classical small molecule blockade to gene therapy approaches, and include the use of potassium channels as targets for adjuvant therapy. We will discuss the reasons for these proposals and explore possible future developments.
Collapse
|
34
|
Catacuzzeno L, Aiello F, Fioretti B, Sforna L, Castigli E, Ruggieri P, Tata AM, Calogero A, Franciolini F. Serum-activated K and Cl currents underlay U87-MG glioblastoma cell migration. J Cell Physiol 2011; 226:1926-33. [PMID: 21506123 DOI: 10.1002/jcp.22523] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Glioblastoma cells in vivo are exposed to a variety of promigratory signals, including undefined serum components that infiltrate into high grade gliomas as result of blood-brain barrier breakdown. Glioblastoma cell migration has been further shown to depend heavily on ion channels activity. We have then investigated the modulatory effects of fetal calf serum (FCS) on ion channels, and their involvement in U87-MG cells migration. Using the perforated patch-clamp technique we have found that, in a subpopulation of cells (42%), FCS induced: (1) an oscillatory activity of TRAM-34 sensitive, intermediate-conductance calcium-activated K (IK(Ca) ) channels, mediated by calcium oscillations previously shown to be induced by FCS in this cell line; (2) a stable activation of a DIDS- and NPPB-sensitive Cl current displaying an outward rectifying instantaneous current-voltage relationship and a slow, voltage-dependent inactivation. By contrast, in another subpopulation of cells (32%) FCS induced a single, transient IK(Ca) current activation, always accompanied by a stable activation of the Cl current. The remaining cells did not respond to FCS. In order to understand whether the FCS-induced ion channel activities are instrumental to promoting cell migration, we tested the effects of TRAM-34 and DIDS on the FCS-induced U87-MG cell migration using transwell migration assays. We found that these inhibitors were able to markedly reduce U87-MG cell migration in the presence of FCS, and that their co-application resulted in an almost complete arrest of migration. It is concluded that the modulation of K and Cl ion fluxes is essential for the FCS-induced glioblastoma cell migration.
Collapse
Affiliation(s)
- Luigi Catacuzzeno
- Dipartimento di Biologia Cellulare e Ambientale, Universita' di Perugia, Perugia, Italy.
| | | | | | | | | | | | | | | | | |
Collapse
|
35
|
Calcium-activated potassium channels BK and IK1 are functionally expressed in human gliomas but do not regulate cell proliferation. PLoS One 2010; 5:e12304. [PMID: 20808839 PMCID: PMC2924897 DOI: 10.1371/journal.pone.0012304] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2010] [Accepted: 07/25/2010] [Indexed: 01/15/2023] Open
Abstract
Gliomas are morbid brain tumors that are extremely resistant to available chemotherapy and radiology treatments. Some studies have suggested that calcium-activated potassium channels contribute to the high proliferative potential of tumor cells, including gliomas. However, other publications demonstrated no role for these channels or even assigned them antitumorogenic properties. In this work we characterized the expression and functional contribution to proliferation of Ca2+-activated K+ channels in human glioblastoma cells. Quantitative RT-PCR detected transcripts for the big conductance (BK), intermediate conductance (IK1), and small conductance (SK2) K+ channels in two glioblastoma-derived cell lines and a surgical sample of glioblastoma multiforme. Functional expression of BK and IK1 in U251 and U87 glioma cell lines and primary glioma cultures was verified using whole-cell electrophysiological recordings. Inhibitors of BK (paxilline and penitrem A) and IK1 channels (clotrimazole and TRAM-34) reduced U251 and U87 proliferation in an additive fashion, while the selective blocker of SK channels UCL1848 had no effect. However, the antiproliferative properties of BK and IK1 inhibitors were seen at concentrations that were higher than those necessary to inhibit channel activity. To verify specificity of pharmacological agents, we downregulated BK and IK1 channels in U251 cells using gene-specific siRNAs. Although siRNA knockdowns caused strong reductions in the BK and IK1 current densities, neither single nor double gene silencing significantly affected rates of proliferation. Taken together, these results suggest that Ca2+-activated K+ channels do not play a critical role in proliferation of glioma cells and that the effects of pharmacological inhibitors occur through their off-target actions.
Collapse
|
36
|
Sciaccaluga M, Fioretti B, Catacuzzeno L, Pagani F, Bertollini C, Rosito M, Catalano M, D'Alessandro G, Santoro A, Cantore G, Ragozzino D, Castigli E, Franciolini F, Limatola C. CXCL12-induced glioblastoma cell migration requires intermediate conductance Ca2+-activated K+ channel activity. Am J Physiol Cell Physiol 2010; 299:C175-84. [DOI: 10.1152/ajpcell.00344.2009] [Citation(s) in RCA: 78] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The activation of ion channels is crucial during cell movement, including glioblastoma cell invasion in the brain parenchyma. In this context, we describe for the first time the contribution of intermediate conductance Ca2+-activated K (IKCa) channel activity in the chemotactic response of human glioblastoma cell lines, primary cultures, and freshly dissociated tissues to CXC chemokine ligand 12 (CXCL12), a chemokine whose expression in glioblastoma has been correlated with its invasive capacity. We show that blockade of the IKCa channel with its specific inhibitor 1-[(2-chlorophenyl) diphenylmethyl]-1 H-pyrazole (TRAM-34) or IKCa channel silencing by short hairpin RNA (shRNA) completely abolished CXCL12-induced cell migration. We further demonstrate that this is not a general mechanism in glioblastoma cell migration since epidermal growth factor (EGF), which also activates IKCa channels in the glioblastoma-derived cell line GL15, stimulate cell chemotaxis even if the IKCa channels have been blocked or silenced. Furthermore, we demonstrate that both CXCL12 and EGF induce Ca2+ mobilization and IKCa channel activation but only CXCL12 induces a long-term upregulation of the IKCa channel activity. Furthermore, the Ca2+-chelating agent BAPTA-AM abolished the CXCL12-induced, but not the EGF-induced, glioblastoma cell chemotaxis. In addition, we demonstrate that the extracellular signal-regulated kinase (ERK)1/2 pathway is only partially implicated in the modulation of CXCL12-induced glioblastoma cell movement, whereas the phosphoinositol-3 kinase (PI3K) pathway is not involved. In contrast, EGF-induced glioblastoma migration requires both ERK1/2 and PI3K activity. All together these findings suggest that the efficacy of glioblastoma invasiveness might be related to an array of nonoverlapping mechanisms activated by different chemotactic agents.
Collapse
Affiliation(s)
- Miriam Sciaccaluga
- Istituto Pasteur-Fondazione Cenci Bolognetti and Department of Physiology and Pharmacology, and
| | - Bernard Fioretti
- Department of Cellular and Environmental Biology, University of Perugia, Perugia; and
| | - Luigi Catacuzzeno
- Department of Cellular and Environmental Biology, University of Perugia, Perugia; and
| | - Francesca Pagani
- Istituto Pasteur-Fondazione Cenci Bolognetti and Department of Physiology and Pharmacology, and
| | - Cristina Bertollini
- Istituto Pasteur-Fondazione Cenci Bolognetti and Department of Physiology and Pharmacology, and
| | - Maria Rosito
- Istituto Pasteur-Fondazione Cenci Bolognetti and Department of Physiology and Pharmacology, and
| | - Myriam Catalano
- Istituto Pasteur-Fondazione Cenci Bolognetti and Department of Physiology and Pharmacology, and
| | - Giuseppina D'Alessandro
- Istituto Pasteur-Fondazione Cenci Bolognetti and Department of Physiology and Pharmacology, and
| | - Antonio Santoro
- Department of Neurological Science, Sapienza University of Rome, Rome
| | | | - Davide Ragozzino
- Istituto Pasteur-Fondazione Cenci Bolognetti and Department of Physiology and Pharmacology, and
| | - Emilia Castigli
- Department of Cellular and Environmental Biology, University of Perugia, Perugia; and
| | - Fabio Franciolini
- Department of Cellular and Environmental Biology, University of Perugia, Perugia; and
| | - Cristina Limatola
- Istituto Pasteur-Fondazione Cenci Bolognetti and Department of Physiology and Pharmacology, and
- Neuromed IRCCS, Via Atinese, Pozzilli, Italy
| |
Collapse
|
37
|
An investigation of the occurrence and properties of the mitochondrial intermediate-conductance Ca2+-activated K+ channel mtKCa3.1. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2009; 1797:1260-7. [PMID: 20036632 DOI: 10.1016/j.bbabio.2009.12.015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2009] [Revised: 12/15/2009] [Accepted: 12/19/2009] [Indexed: 12/24/2022]
Abstract
The mitochondrial intermediate-conductance Ca2+-activated K+ channel mtKCa3.1 has recently been discovered in the HCT116 colon tumor-derived cell line, which expresses relatively high levels of this protein also in the plasma membrane. Electrophysiological recordings revealed that the channel can exhibit different conductance states and kinetic modes, which we tentatively ascribe to post-translational modifications. To verify whether the localization of this channel in mitochondria might be a peculiarity of these cells or a more widespread feature we have checked for the presence of mtKCa3.1 in a few other cell lines using biochemical and electrophysiological approaches. It turned out to be present at least in some of the cells investigated. Functional assays explored the possibility that mtKCa3.1 might be involved in cell proliferation or play a role similar to that of the Shaker-type KV1.3 channel in lymphocytes, which interacts with outer mitochondrial membrane-inserted Bax thereby promoting apoptosis (Szabò, I. et al., Proc. Natl. Acad Sci. USA 105 (2008) 14861-14866). A specific KCa3.1 inhibitor however did not have any detectable effect on cell proliferation or death.
Collapse
|
38
|
Renal fibrosis is attenuated by targeted disruption of KCa3.1 potassium channels. Proc Natl Acad Sci U S A 2009; 106:14518-23. [PMID: 19706538 DOI: 10.1073/pnas.0903458106] [Citation(s) in RCA: 131] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Proliferation of interstitial fibroblasts is a hallmark of progressive renal fibrosis commonly resulting in chronic kidney failure. The intermediate-conductance Ca(2+)-activated K(+) channel (K(Ca)3.1) has been proposed to promote mitogenesis in several cell types and contribute to disease states characterized by excessive proliferation. Here, we hypothesized that K(Ca)3.1 activity is pivotal for renal fibroblast proliferation and that deficiency or pharmacological blockade of K(Ca)3.1 suppresses development of renal fibrosis. We found that mitogenic stimulation up-regulated K(Ca)3.1 in murine renal fibroblasts via a MEK-dependent mechanism and that selective blockade of K(Ca)3.1 functions potently inhibited fibroblast proliferation by G(0)/G(1) arrest. Renal fibrosis induced by unilateral ureteral obstruction (UUO) in mice was paralleled by a robust up-regulation of K(Ca)3.1 in affected kidneys. Mice lacking K(Ca)3.1 (K(Ca)3.1(-/-)) showed a significant reduction in fibrotic marker expression, chronic tubulointerstitial damage, collagen deposition and alphaSMA(+) cells in kidneys after UUO, whereas functional renal parenchyma was better preserved. Pharmacological treatment with the selective K(Ca)3.1 blocker TRAM-34 similarly attenuated progression of UUO-induced renal fibrosis in wild-type mice and rats. In conclusion, our data demonstrate that K(Ca)3.1 is involved in renal fibroblast proliferation and fibrogenesis and suggest that K(Ca)3.1 may represent a therapeutic target for the treatment of fibrotic kidney disease.
Collapse
|
39
|
Fioretti B, Catacuzzeno L, Sforna L, Aiello F, Pagani F, Ragozzino D, Castigli E, Franciolini F. Histamine hyperpolarizes human glioblastoma cells by activating the intermediate-conductance Ca2+-activated K+ channel. Am J Physiol Cell Physiol 2009; 297:C102-10. [PMID: 19420000 DOI: 10.1152/ajpcell.00354.2008] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The effects of histamine on the membrane potential and currents of human glioblastoma (GL-15) cells were investigated. In perforated whole cell configuration, short (3 s) applications of histamine (100 microM) hyperpolarized the membrane by activating a K(+)-selective current. The response involved the activation of the pyrilamine-sensitive H(1) receptor and Ca(2+) release from thapsigargin-sensitive intracellular stores. The histamine-activated current was insensitive to tetraethylammonium (3 mM), iberiotoxin (100 nM), and d-tubocurarine (100 microM) but was markedly inhibited by charybdotoxin (100 nM), clotrimazole (1 microM), and 1-[(2-chlorophenyl)diphenylmethyl]-1H-pyrazole (TRAM-34, 1 microM), a pharmacological profile congruent with the intermediate conductance Ca(2+)-activated K(+) (IK(Ca)) channel. Cell-attached recordings confirmed that histamine activated a K(+) channel with properties congruent with the IK(Ca) channel (voltage independence, 22 pS unitary conductance and slight inward rectification in symmetrical 140 mM K(+)). More prolonged histamine applications (2-3 min) often evoked a sustained IK(Ca) channel activity, which depended on a La(2+) (10 microM)-sensitive Ca(2+) influx. Intracellular Ca(2+) measurements revealed that the sustained IK(Ca) channel activity enhanced the histamine-induced Ca(2+) signal, most likely by a hyperpolarization-induced increase in the driving force for Ca(2+) influx. In virtually all cells examined we also observed the expression of the large conductance Ca(2+)-activated K(+) (BK(Ca)) channel, with a unitary conductance of ca. 230 pS in symmetrical 140 mM K(+), and a Ca(2+) dissociation constant [K(D(Ca))] of ca. 3 microM, at -40 mV. Notably in no instance was the BK(Ca) channel activated by histamine under physiological conditions. The most parsimonious explanation based on the different K(D(Ca)) for the two K(Ca) channels is provided.
Collapse
Affiliation(s)
- Bernard Fioretti
- Dip. Biologia Cellulare e Ambientale, Universita' di Perugia, 1 I-06123 Perugia, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
40
|
De Marchi U, Sassi N, Fioretti B, Catacuzzeno L, Cereghetti GM, Szabò I, Zoratti M. Intermediate conductance Ca2+-activated potassium channel (KCa3.1) in the inner mitochondrial membrane of human colon cancer cells. Cell Calcium 2009; 45:509-16. [PMID: 19406468 DOI: 10.1016/j.ceca.2009.03.014] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Revised: 03/13/2009] [Accepted: 03/23/2009] [Indexed: 11/28/2022]
Abstract
Patch-clamping mitoplasts isolated from human colon carcinoma 116 cells has allowed the identification and characterization of the intermediate conductance Ca(2+)-activated K(+)-selective channel K(Ca)3.1, previously studied only in the plasma membrane of various cell types. Its identity has been established by its biophysical and pharmacological properties. Its localisation in the inner membrane of mitochondria is indicated by Western blots of subcellular fractions, by recording of its activity in mitochondria made fluorescent by a mitochondria-targeted fluorescent protein and by the co-presence of channels considered to be markers of the inner membrane. Moderate increases of mitochondrial matrix [Ca(2+)] will cause mtK(Ca)3.1 opening, thus linking inner membrane K(+) permeability and transmembrane potential to Ca(2+) signalling.
Collapse
Affiliation(s)
- Umberto De Marchi
- Department of Biomedical Sciences, University of Padova, Padova, Italy
| | | | | | | | | | | | | |
Collapse
|
41
|
Buratta M, Castigli E, Sciaccaluga M, Pellegrino RM, Spinozzi F, Roberti R, Corazzi L. Loss of cardiolipin in palmitate-treated GL15 glioblastoma cells favors cytochrome c release from mitochondria leading to apoptosis. J Neurochem 2008; 105:1019-31. [DOI: 10.1111/j.1471-4159.2007.05209.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
42
|
Ross SB, Fuller CM, Bubien JK, Benos DJ. Amiloride-sensitive Na+ channels contribute to regulatory volume increases in human glioma cells. Am J Physiol Cell Physiol 2007; 293:C1181-5. [PMID: 17615161 DOI: 10.1152/ajpcell.00066.2007] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Despite intensive research, brain tumors remain among the most difficult type of malignancies to treat, due largely to their diffusely invasive nature and the associated difficulty of adequate surgical resection. To migrate through the brain parenchyma and to proliferate, glioma cells must be capable of significant changes in shape and volume. We have previously reported that glioma cells express an amiloride- and psalmotoxin-sensitive cation conductance that is not found in normal human astrocytes. In the present study, we investigated the potential role of this ion channel to mediate regulatory volume increase in glioma cells. We found that the ability of the cells to volume regulate subsequent to cell shrinkage by hyperosmolar solutions was abolished by both amiloride and psalmotoxin 1. This toxin is thought to be a specific peptide inhibitor of acid-sensing ion channel (ASIC1), a member of the Deg/ENaC superfamily of cation channels. We have previously shown this toxin to be an effective blocker of the glioma cation conductance. Our data suggest that one potential role for this conductance may be to restore cell volume during the cell's progression thorough the cell cycle and while the tumor cell migrates within the interstices of the brain.
Collapse
Affiliation(s)
- Sandra B Ross
- Dept. Physiology and Biophysics, Univ. of Alabama at Birmingham, 1918 University Blvd., MCLM 704, Birmingham, AL 35294-0005, USA.
| | | | | | | |
Collapse
|