title: 8-Cl-cAMP affects glioma cell-cycle kinetics and selectively induces apoptosis.
abstract: 8-Chloro-cyclic-adenosine-3',5'-monophosphate (8-Cl-cAMP), a site-selective synthetic cyclic adenosine 3',5'-monophosphate (cAMP) analog exhibits growth inhibition in a broad spectrum of human cancer lines. However, detailed studies on the effects exerted by cAMP analogs on cell-cycle kinetics have been lacking. We have examined and compared the effect of 8-Cl-cAMP on cell-cycle kinetics in two human glioma cell lines, U87MG (p53wt) and U251MG (p53mt). A flow cytometric analysis of cell-cycle distribution as well as apoptosis evaluation were performed by univariate DNA analysis after 24-72 hr of treatment with 10-50 M concentrations of 8-Cl-cAMP. Longer incubation with 8-Cl-cAMP induced dose related accumulation of cells in S phase and a subsequent decrease in the proportion of cells in G0/G1 phase of cell cycle in both cell lines. Time-dependent suppression of cyclin B1 was detected in both glioma cell lines and could be associated with observed G2 delay. However, 8-aCl-cAMP selectively induced apoptotic cell death only in U87MG, but not in U251MG cells. Induction of apoptosis was revealed both by flow cytometry and apoptotic cell morphology. These results provide an insight into the mechanism of 8-aCl-cAMP action, suggesting that the disturbance of cell-cycle kinetics and induction of apoptosis might contribute to its growth-inhibitory effect on cancer cells.
authors.affiliation: Laboratory of Molecular Neurobiology, Department of Neurobiology and Immunology, Institute for Biological Research, 29 Novembar 142, 11000 Belgrade, Yugoslavia.
authors.forename: Olivera
authors.initials: O
authors.lastname: Grbovic
authors.forename: Viktor
authors.initials: V
authors.lastname: Jovic
authors.forename: Sabera
authors.initials: S
authors.lastname: Ruzdijic
authors.forename: Vjera
authors.initials: V
authors.lastname: Pejanovic
authors.forename: Ljubisav
authors.initials: L
authors.lastname: Rakic
authors.forename: Selma
authors.initials: S
authors.lastname: Kanazir
mesh_terms: D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000031:analogs & derivatives* / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D001932:Brain Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D002453:Cell Cycle / Q000187:drug effects*; D019926:Cyclin B / Q000235:genetics / Q000378:metabolism; D056744:Cyclin B1; D017931:DNA Primers / Q000737:chemistry; D005434:Flow Cytometry; D016195:G2 Phase; D005910:Glioma / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D020287:In Situ Nick-End Labeling; D007700:Kinetics; D009154:Mutation; D020133:Reverse Transcriptase Polymerase Chain Reaction; D016196:S Phase; D014407:Tumor Cells, Cultured / Q000187:drug effects* / Q000378:metabolism; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; C534699:CCNB1 protein, human; D019926:Cyclin B; D056744:Cyclin B1; D017931:DNA Primers; D016159:Tumor Suppressor Protein p53; D015124:8-Bromo Cyclic Adenosine Monophosphate; C044258:8-chloro-cyclic adenosine monophosphate