title: 4-Hydroxynonenal induces G2/M phase cell cycle arrest by activation of the ataxia telangiectasia mutated and Rad3-related protein (ATR)/checkpoint kinase 1 (Chk1) signaling pathway.
abstract: 4-Hydroxynonenal (HNE) has been widely implicated in the mechanisms of oxidant-induced toxicity, but the detrimental effects of HNE associated with DNA damage or cell cycle arrest have not been thoroughly studied. Here we demonstrate for the first time that HNE caused G2/M cell cycle arrest of hepatocellular carcinoma HepG2 (p53 wild type) and Hep3B (p53 null) cells that was accompanied with decreased expression of CDK1 and cyclin B1 and activation of p21 in a p53-independent manner. HNE treatment suppressed the Cdc25C level, which led to inactivation of CDK1. HNE-induced phosphorylation of Cdc25C at Ser-216 resulted in its translocation from nucleus to cytoplasm, thereby facilitating its degradation via the ubiquitin-mediated proteasomal pathway. This phosphorylation of Cdc25C was regulated by activation of the ataxia telangiectasia and Rad3-related protein (ATR)/checkpoint kinase 1 (Chk1) pathway. The role of HNE in the DNA double strand break was strongly suggested by a remarkable increase in comet tail formation and H2A.X phosphorylation in HNE-treated cells in vitro. This was supported by increased in vivo phosphorylation of H2A.X in mGsta4 null mice that have impaired HNE metabolism and increased HNE levels in tissues. HNE-mediated ATR/Chk1 signaling was inhibited by ATR kinase inhibitor (caffeine). Additionally, most of the signaling effects of HNE on cell cycle arrest were attenuated in hGSTA4 transfected cells, thereby indicating the involvement of HNE in these events. A novel role of GSTA4-4 in the maintenance of genomic integrity is also suggested.
authors.affiliation: Department of Molecular Biology and Immunology and Institute for Cancer Research, University of North Texas Health Science Center, Fort Worth, Texas 76107, USA.
authors.forename: Pankaj
authors.initials: P
authors.lastname: Chaudhary
authors.forename: Rajendra
authors.initials: R
authors.lastname: Sharma
authors.forename: Mukesh
authors.initials: M
authors.lastname: Sahu
authors.forename: Jamboor K
authors.initials: JK
authors.lastname: Vishwanatha
authors.forename: Sanjay
authors.initials: S
authors.lastname: Awasthi
authors.forename: Yogesh C
authors.initials: YC
authors.lastname: Awasthi
mesh_terms: D000447:Aldehydes / Q000494:pharmacology*; D000818:Animals; D064007:Ataxia Telangiectasia Mutated Proteins; D015153:Blotting, Western; D016203:CDC2 Protein Kinase / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism*; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D000071877:Checkpoint Kinase 1; D056744:Cyclin B1 / Q000378:metabolism; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D059565:G2 Phase Cell Cycle Checkpoints / Q000187:drug effects*; D005982:Glutathione Transferase / Q000235:genetics / Q000378:metabolism; D056945:Hep G2 Cells; D006657:Histones / Q000378:metabolism; D006801:Humans; D008099:Liver / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D018613:Microscopy, Confocal; D010766:Phosphorylation / Q000187:drug effects; D011494:Protein Kinases / Q000378:metabolism*; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D034622:RNA Interference; D015398:Signal Transduction / Q000187:drug effects*; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism
chemical_list: D000447:Aldehydes; D018797:Cell Cycle Proteins; D056744:Cyclin B1; D015853:Cysteine Proteinase Inhibitors; C468783:H2AX protein, human; D006657:Histones; D016159:Tumor Suppressor Protein p53; D005982:Glutathione Transferase; D011494:Protein Kinases; C576597:ATR protein, human; D064007:Ataxia Telangiectasia Mutated Proteins; C000605867:CHEK1 protein, human; D000071877:Checkpoint Kinase 1; C000605869:Chek1 protein, mouse; D017346:Protein Serine-Threonine Kinases; D016203:CDC2 Protein Kinase; C041116:leukotriene-C4 synthase; C027576:4-hydroxy-2-nonenal
keywords: 4-Hydroxynonenal; Cell Cycle; Cell Cycle Arrest; DNA Damage; Glutathione S-Tranferase; Lipid Peroxidation; Oxidative Stress; Signal Transduction