title: Molecular mechanisms of apoptosis in HL-60 cells induced by a nitric oxide-releasing compound.
abstract: Nitric oxide (NO) generated from 1-hydroxy-2-oxo-3, 3-bis(2-aminoethyl)-1-triazene (NOC 18), an NO-releasing compound, induced monocytic differentiation of human promyelocytic leukemia HL-60 cells as assessed by expression of nonspecific esterases and morphologic maturation. Simultaneously, DNA fragmentation and morphological alterations typical of apoptosis were also induced. To investigate the mechanisms of apoptosis during differentiation of HL-60 cells induced by NO, the endogenous levels of Bcl-2 and Bax were assessed by immunoblotting. Treatment of cells with NOC 18 slightly reduced the level of Bcl-2 followed by Bax. These changes might be involved in the induction of apoptosis. The involvement of the activation of the interleukin-1 beta converting enzyme (ICE) family of proteases (caspases), such as ICE and CPP32, in the pathways was also investigated. CPP32, but not ICE, was strongly activated in response to NOC 18 stimulation, thereby implicating CPP32-like activity in the induction of apoptosis. Moreover, the possible involvement of tyrosine phosphorylation in apoptosis was investigated. Pretreatment of cells with herbimycin A, an inhibitor of tyrosine kinases, suppressed DNA fragmentation and CPP32-like activity, whereas pretreatment with vanadate, an inhibitor of tyrosine phosphatases, enhanced both parameters, suggesting that tyrosine phosphorylation might be involved in the pathways of apoptosis in HL-60 cells induced by NO.
authors.affiliation: Department of Cell Chemistry, Okayama University Medical School, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Yabuki
authors.forename: S
authors.initials: S
authors.lastname: Kariya
authors.forename: Y
authors.initials: Y
authors.lastname: Inai
authors.forename: K
authors.initials: K
authors.lastname: Hamazaki
authors.forename: T
authors.initials: T
authors.lastname: Yoshioka
authors.forename: T
authors.initials: T
authors.lastname: Yasuda
authors.forename: A A
authors.initials: AA
authors.lastname: Horton
authors.forename: K
authors.initials: K
authors.lastname: Utsumi
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D016227:Benzoquinones; D020170:Caspase 1; D053148:Caspase 3; D020169:Caspases; D002454:Cell Differentiation / Q000187:drug effects; D002455:Cell Division / Q000187:drug effects; D003546:Cysteine Endopeptidases / Q000378:metabolism; D053938:DNA Fragmentation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018922:HL-60 Cells / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D006801:Humans; D007700:Kinetics; D047029:Lactams, Macrocyclic; D009000:Monocytes / Q000166:cytology / Q000187:drug effects; D009569:Nitric Oxide / Q000494:pharmacology*; D009603:Nitroso Compounds / Q000494:pharmacology*; D011809:Quinones / Q000494:pharmacology; D017828:Rifabutin / Q000031:analogs & derivatives; D013379:Substrate Specificity; D014638:Vanadates / Q000494:pharmacology
chemical_list: D016227:Benzoquinones; D004791:Enzyme Inhibitors; D047029:Lactams, Macrocyclic; C093285:NOC 18; D009603:Nitroso Compounds; D011809:Quinones; D017828:Rifabutin; D009569:Nitric Oxide; D014638:Vanadates; C020754:herbimycin; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D003546:Cysteine Endopeptidases; D020170:Caspase 1