title: Poly(ADPR)polymerase-1 signalling of the DNA damage induced by DNA topoisomerase I poison in D54(p53wt) and U251(p53mut) glioblastoma cell lines.
abstract: Glioblastomas are widely characterised by the mutation of the p53 gene and p53 disruption sensitizes glioblastoma cells to DNA topoisomerase I (TOPO I) inhibitor-mediated apoptosis. We investigated the effects of combined treatments with the DNA topoisomerase I inhibitor Topotecan and the poly(ADPR)polymerase-1 inhibitor NU1025 in D54(p53wt) and U251(p53mut) glioblastoma cell lines. Analysis of cell growth and cell cycle kinetics showed a synergistic anti-proliferative effect of 10 nM TPT and 10 microM NU1025 and a G2/M block of the cell cycle. We also evaluated, the influence of TPT+/-NU1025 treatment on PARP-1 and p53 activity. We got evidences of a TPT-dependent increase of PARP-1 auto-modification level in both the cells. Moreover, in the D54(p53wt) cells we found that in co-treatments NU1025 incremented the TPT-dependent stimulation of p53 transcriptional activity and increased the p21 nuclear amount. Conversely, in U251(p53mut) cells we found that NU1025 incremented the TPT-dependent apoptosis characterised by PARP-1 proteolysis. Our findings suggest that the modulation of PARP-1 can be considered a strategy in the potentiation of the chemotherapeutic action of TOPO I poisons in glioblastoma cells apart from their p53 status.
authors.affiliation: Department of Functional and Structural Biology, University Federico II, Naples, Italy.
authors.forename: Gabriella
authors.initials: G
authors.lastname: Cimmino
authors.forename: Stefano
authors.initials: S
authors.lastname: Pepe
authors.forename: Gianluca
authors.initials: G
authors.lastname: Laus
authors.forename: Maria
authors.initials: M
authors.lastname: Chianese
authors.forename: Daniela
authors.initials: D
authors.lastname: Prece
authors.forename: Romina
authors.initials: R
authors.lastname: Penitente
authors.forename: Piera
authors.initials: P
authors.lastname: Quesada
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D001932:Brain Neoplasms / Q000201:enzymology / Q000235:genetics / Q000503:physiopathology*; D045744:Cell Line, Tumor; D002467:Cell Nucleus / Q000737:chemistry / Q000201:enzymology; D004249:DNA Damage / Q000502:physiology*; D004264:DNA Topoisomerases, Type I; D003720:Densitometry; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004791:Enzyme Inhibitors / Q000506:poisoning; D005434:Flow Cytometry; D005909:Glioblastoma / Q000201:enzymology / Q000235:genetics / Q000503:physiopathology*; D006801:Humans; D020287:In Situ Nick-End Labeling; D007202:Indicators and Reagents; D009154:Mutation / Q000502:physiology; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000502:physiology*; D011799:Quinazolines / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects; D019772:Topotecan / Q000506:poisoning; D016159:Tumor Suppressor Protein p53 / Q000235:genetics
chemical_list: D004791:Enzyme Inhibitors; D007202:Indicators and Reagents; C115774:NU 1025; D011799:Quinazolines; D016159:Tumor Suppressor Protein p53; D019772:Topotecan; C499320:PARP1 protein, human; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D004264:DNA Topoisomerases, Type I