title: S100B-p53 disengagement by pentamidine promotes apoptosis and inhibits cellular migration via aquaporin-4 and metalloproteinase-2 inhibition in C6 glioma cells.
abstract: S100 calcium-binding protein B (S100B) is highly expressed in glioma cells and promotes cancer cell survival via inhibition of the p53 protein. In melanoma cells, this S100B-p53 interaction is known to be inhibited by pentamidine isethionate, an antiprotozoal agent. Thus, the aim of the present study was to evaluate the effect of pentamidine on rat C6 glioma cell proliferation, migration and apoptosisin vitro. The change in C6 cell proliferation following treatment with pentamidine was determined by performing a 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide-formazan assay. Significant dose-dependent decreases in proliferation were observed at pentamidine concentrations of 0.05 µM (58.5±5%; P<0.05), 0.5 µM (40.6±7%; P<0.01) and 5 µM (13±4%; P<0.001) compared with the control (100% viability). Furthermore, treatment with 0.05, 0.5 and 5 µM pentamidine was associated with a significant increase in apoptosis versus the untreated cells, as determined by DNA fragmentation assays, immunofluorescence analysis of C6 chromatin using Hoechst staining, and immunoblot analysis of B-cell lymphoma-2 (Bcl-2)-associated X protein (100%, P<0.05; 453%, P<0.01; and 1000%, P<0.001, respectively) and Bcl-2 (-60%, P<0.001; -80.13%, P<0.001; -95%, P<0.001, respectively). In addition, the administration of 0.05, 0.5 and 5 µM pentamidine significantly upregulated the protein expression levels of p53 (681±87.5%, P<0.05; 1244±94.3%, P<0.01; and 2244±111%, P<0.001, respectively), and significantly downregulated the expression levels of matrix metalloproteinase-2 (42±2.3%, P<0.05; 71±2.5%, P<0.01; and 95.8±3.3%, P<0.001, respectively) and aquaporin 4 (38±2.5%, P<0.05; 69±2.6%, P<0.01; and 88±3.0%, P<0.001, respectively), compared with the untreated cells. The wound healing assay demonstrated that cell migration was significantly impaired by treatment with 0.05, 0.5 and 5 µM pentamidine compared with untreated cells (88±4.2%, P<0.05; 64±2%, P<0.01; and 42±3.1%, P<0.001, respectively). Although additionalin vivostudies are required to clarify the currentin vitrodata, the present study indicates that pentamidine and S100B-p53 inhibitors may represent a novel approach for the treatment of glioma.
authors.affiliation: Department of Physiology and Pharmacology 'Vittorio Erspamer', Sapienza University of Rome, Rome I-00185, Italy.
authors.forename: Elena
authors.initials: E
authors.lastname: Capoccia
authors.affiliation: Laboratory for Enteric Neuroscience, Translational Research Center for Gastrointestinal Disorders, University of Leuven, Leuven 3000, Belgium.
authors.forename: Carla
authors.initials: C
authors.lastname: Cirillo
authors.affiliation: Department of Physiology and Pharmacology 'Vittorio Erspamer', Sapienza University of Rome, Rome I-00185, Italy.
authors.forename: Annalisa
authors.initials: A
authors.lastname: Marchetto
authors.affiliation: Department of Physiology and Pharmacology 'Vittorio Erspamer', Sapienza University of Rome, Rome I-00185, Italy.
authors.forename: Samanta
authors.initials: S
authors.lastname: Tiberi
authors.affiliation: Department of Physiology and Pharmacology 'Vittorio Erspamer', Sapienza University of Rome, Rome I-00185, Italy.
authors.forename: Youssef
authors.initials: Y
authors.lastname: Sawikr
authors.affiliation: Department of Clinical and Experimental Medicine, Gastroenterology Unit, University of Naples Federico II, Naples I-80131, Italy.
authors.forename: Marcella
authors.initials: M
authors.lastname: Pesce
authors.affiliation: Department of Clinical and Experimental Medicine, Gastroenterology Unit, University of Naples Federico II, Naples I-80131, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: D'Alessandro
authors.affiliation: Department of Physiology and Pharmacology 'Vittorio Erspamer', Sapienza University of Rome, Rome I-00185, Italy.
authors.forename: Caterina
authors.initials: C
authors.lastname: Scuderi
authors.affiliation: Department of Clinical and Experimental Medicine, Gastroenterology Unit, University of Naples Federico II, Naples I-80131, Italy.
authors.forename: Giovanni
authors.initials: G
authors.lastname: Sarnelli
authors.affiliation: Department of Clinical and Experimental Medicine, Gastroenterology Unit, University of Naples Federico II, Naples I-80131, Italy.
authors.forename: Rosario
authors.initials: R
authors.lastname: Cuomo
authors.affiliation: Department of Physiology and Pharmacology 'Vittorio Erspamer', Sapienza University of Rome, Rome I-00185, Italy.
authors.forename: Luca
authors.initials: L
authors.lastname: Steardo
authors.affiliation: Department of Physiology and Pharmacology 'Vittorio Erspamer', Sapienza University of Rome, Rome I-00185, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Esposito
keywords: S100 calcium-binding protein B; glioma cells; p53; pentamidine