Role of reactive oxygen species and MAPKs in vanadate-induced G(2)/M phase arrest.
Cell growth arrest is an important mechanism in maintaining genomic stability and integrity in response to environmental stress. Using the human lung alveolar epithelial cancer cell line A549, we investigated the role of reactive oxygen species (ROS), extracellular signal-regulated protein kinase (ERK), and p38 protein kinase in vanadate-induced cell growth arrest. Exposure of cells to vanadate led to cell growth arrest at the G(2)/M phase and caused upregulation of p21 and phospho-cdc2 and degradation of cdc25C in a time- and dose-dependent manner. Vanadate stimulated mitogen-activated protein kinases (MAPKs) family members, as determined by the phosphorylation of ERK and p38. PD98059, an inhibitor of ERK, and SB202190, an inhibitor of p38, inhibited vanadate-induced cell growth arrest, upregulation of p21 and cdc2, and degradation of cdc25C. In addition to hydroxyl radical ((*)OH) formation, cellular reduction of vanadate generated superoxide radical (O(2)(*)(-)) and hydrogen peroxide (H(2)O(2)), as determined by confocal microscopy using specific dyes. Generation of O(2)(*)(-) and H(2)O(2) was inhibited by specific antioxidant enzymes, superoxide dismutase (SOD) and catalase, respectively. ROS activate ERK and p38, which in turn upregulate p21 and cdc2 and cause degradation of cdc25C, leading to cell growth arrest at the G(2)/M phase. Specific ROS affect different MAPK family members and cell growth regulatory proteins with different potencies.
Pathology and Physiology Research Branch, National Institute for Occupational Safety and Health, Morgantown, WV 26505, USA.
Zhuo
Z
Zhang
Stephen S
SS
Leonard
Chuanshu
C
Huang
Val
V
Vallyathan
Vince
V
Castranova
Xianglin
X
Shi
D000975:Antioxidants / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects; D015153:Blotting, Western; D016203:CDC2 Protein Kinase / Q000378:metabolism; D002374:Catalase / Q000494:pharmacology; D018797:Cell Cycle Proteins / Q000378:metabolism; D002478:Cells, Cultured; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D005419:Flavonoids / Q000494:pharmacology; D016195:G2 Phase / Q000187:drug effects*; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D018613:Microscopy, Confocal; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008938:Mitosis / Q000187:drug effects*; D010766:Phosphorylation; D011650:Pulmonary Alveoli / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D017382:Reactive Oxygen Species; D013482:Superoxide Dismutase / Q000494:pharmacology; D013481:Superoxides / Q000378:metabolism; D014638:Vanadates / Q000494:pharmacology*; D020687:cdc25 Phosphatases / Q000378:metabolism; D048051:p38 Mitogen-Activated Protein Kinases
D000975:Antioxidants; C493956:CDKN1A protein, human; D018797:Cell Cycle Proteins; D050759:Cyclin-Dependent Kinase Inhibitor p21; D016213:Cyclins; D004791:Enzyme Inhibitors; D005419:Flavonoids; D017382:Reactive Oxygen Species; D013481:Superoxides; D014638:Vanadates; D006861:Hydrogen Peroxide; D002374:Catalase; D013482:Superoxide Dismutase; D016203:CDC2 Protein Kinase; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; C517009:CDC25C protein, human; D020687:cdc25 Phosphatases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one