MCB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Guo, G.
Right arrow Articles by Li, J. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Guo, G.
Right arrow Articles by Li, J. J.

 Previous Article  |  Next Article 

Molecular and Cellular Biology, April 2003, p. 2362-2378, Vol. 23, No. 7
0270-7306/03/$08.00+0     DOI: 10.1128/MCB.23.7.2362-2378.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

Manganese Superoxide Dismutase-Mediated Gene Expression in Radiation-Induced Adaptive Responses

Guozheng Guo,1 Yan Yan-Sanders,2 Beverly D. Lyn-Cook,2 Tieli Wang,1 Daniel Tamae,1 Julie Ogi,1 Alexander Khaletskiy,1 Zhongkui Li,1 Christine Weydert,3 Jeffrey A. Longmate,4 Ting-Ting Huang,5 Douglas R. Spitz,3 Larry W. Oberley,3 and Jian Jian Li1*

Radiation Biology, Division of Radiation Oncology,1 Biostatistics, Beckman Research Institute, City of Hope National Medical Center, Duarte, California 91010,4 Division of Molecular Epidemiology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, Arkansas 72079,2 Free Radical and Radiation Biology Program, Department of Radiation Oncology, University of Iowa, Iowa City, Iowa 52242,3 Neurology and Neurological Sciences, Stanford University, Palo Alto, California 943045

Received 1 August 2002/ Returned for modification 28 August 2002/ Accepted 8 January 2003

Antioxidant enzymes are critical in oxidative stress responses. Radioresistant variants isolated from MCF-7 human carcinoma cells following fractionated ionizing radiation (MCF+FIR cells) or overexpression of manganese superoxide dismutase (MCF+SOD cells) demonstrated dose-modifying factors at 10% isosurvival of 1.8 and 2.3, respectively. MCF+FIR and MCF-7 cells (exposed to single-dose radiation) demonstrated 5- to 10-fold increases in MnSOD activity, mRNA, and immunoreactive protein. Radioresistance in MCF+FIR and MCF+SOD cells was reduced following expression of antisense MnSOD. DNA microarray analysis and immunoblotting identified p21, Myc, 14-3-3 zeta, cyclin A, cyclin B1, and GADD153 as genes constitutively overexpressed (2- to 10-fold) in both MCF+FIR and MCF+SOD cells. Radiation-induced expression of these six genes was suppressed in fibroblasts from Sod2 knockout mice (-/-) as well as in MCF+FIR and MCF+SOD cells expressing antisense MnSOD. Inhibiting NF-{kappa}B transcriptional activity in MCF+FIR cells, by using mutant I{kappa}B{alpha}, inhibited radioresistance as well as reducing steady-state levels of MnSOD, 14-3-3 zeta, GADD153, cyclin A, and cyclin B1 mRNA. In contrast, mutant I{kappa}B{alpha} was unable to inhibit radioresistance or reduce 14-3-3 zeta, GADD153, cyclin A, and cyclin B1 mRNAs in MCF+SOD cells, where MnSOD overexpression was independent of NF-{kappa}B. These results support the hypothesis that NF-{kappa}B is capable of regulating the expression of MnSOD, which in turn is capable of increasing the expression of genes that participate in radiation-induced adaptive responses.

* Corresponding author. Mailing address: H115 Halper South Building, Beckman Research Institute, City of Hope National Medical Center, 1500 Duarte Rd., Duarte, CA 91010. Phone: (626) 301-8355. Fax: (626) 301-8892. E-mail: jjli{at}coh.org.

Molecular and Cellular Biology, April 2003, p. 2362-2378, Vol. 23, No. 7
0022-538X/03/$08.00+0     DOI: 10.1128/MCB.23.7.2362-2378.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:



Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
J. Bacteriol. J. Virol. Eukaryot. Cell
Microbiol. Mol. Biol. Rev. Clin. Vaccine Immunol. All ASM Journals

Copyright © 2003 by the American Society for Microbiology. All rights reserved.