|
|
||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Molecular & Cellular Proteomics 3:534-547, 2004.
© 2004 by The American Society for Biochemistry and Molecular Biology, Inc.







,¶
From the
Cancer Research UK Laboratories in the Department of Molecular and Cellular Pathology, University of Dundee, Dundee DD1 9SY, United Kingdom; and
University of Aberdeen, UK Protein Sequencing Facility, Aberdeen AB25 2ZD, United Kingdom
The esophageal epithelium is subject to damage from bile acid reflux that promotes normal tissue injury resulting in the development of Barretts epithelium. There is a selection pressure for mutating p53 in this preneoplastic epithelium, thus identifying a physiologically relevant model for discovering novel regulators of the p53 pathway. Proteomic technologies were used to identify such p53 regulatory factors by identifying proteins that were overexpressed in Barretts epithelium. A very abundant polypeptide selectively expressed in Barretts epithelium was identified as anterior gradient-2. Immunochemical methods confirmed that anterior gradient-2 is universally up-regulated in Barretts epithelium, relative to normal squamous tissue derived from the same patient. Transfection of the anterior gradient-2 gene into cells enhances colony formation, similar to mutant oncogenic p53 encoded by the HIS175 allele, suggesting that anterior gradient-2 can function as a survival factor. Deletion of the C-terminal 10 amino acids of anterior gradient-2 neutralizes the colony enhancing activity of the gene, suggesting a key role for this domain in enhancing cell survival. Constitutive overexpression of anterior gradient-2 does not alter cell-cycle parameters in unstressed cells, suggesting that this gene is not directly modifying the cell cycle. However, cells overexpressing anterior gradient-2 attenuate p53 phosphorylation at both Ser15 and Ser392 and silence p53 transactivation function in ultraviolet (UV)-damaged cells. Deletion of the C-terminal 10 amino acids of anterior gradient-2 permits phosphorylation at Ser15 in UV-damaged cells, suggesting that the C-terminal motif promoting colony survival also contributes to suppression of the Ser15 kinase pathway. These data identify anterior gradient-2 as a novel survival factor whose study may shed light on cellular pathways that attenuate the tumor suppressor p53.
![]()
CiteULike
Complore
Connotea
Del.icio.us
Digg
Reddit
Technorati What's this?
This article has been cited by other articles:
![]() |
Z. Wang, Y. Hao, and A. W. Lowe The Adenocarcinoma-Associated Antigen, AGR2, Promotes Tumor Growth, Cell Migration, and Cellular Transformation Cancer Res., January 15, 2008; 68(2): 492 - 497. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Liu, X. Zhang, C.-K. So, S. Wang, P. Wang, L. Yan, R. Myers, Z. Chen, A. P. Patterson, C. S. Yang, et al. Regulation of Cdx2 expression by promoter methylation, and effects of Cdx2 transfection on morphology and gene expression of human esophageal epithelial cells Carcinogenesis, February 1, 2007; 28(2): 488 - 496. [Abstract] [Full Text] [PDF] |
||||
![]() |
R C Fitzgerald Molecular basis of Barrett's oesophagus and oesophageal adenocarcinoma. Gut, December 1, 2006; 55(12): 1810 - 1820. [Full Text] [PDF] |
||||
![]() |
R. N. Morrison, G. A. Cooper, B. F. Koop, M. L. Rise, A. R. Bridle, M. B. Adams, and B. F. Nowak Transcriptome profiling the gills of amoebic gill disease (AGD)-affected Atlantic salmon (Salmo salar L.): a role for tumor suppressor p53 in AGD pathogenesis? Physiol Genomics, September 14, 2006; 26(1): 15 - 34. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| All ASBMB Journals | Journal of Biological Chemistry |
| Journal of Lipid Research | ASBMB Today |