Document Detail


Up-regulation of activation-induced cytidine deaminase causes genetic aberrations at the CDKN2b-CDKN2a in gastric cancer.
MedLine Citation:
PMID:  20637757     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
BACKGROUND & AIMS: The DNA/RNA editing enzyme activation-induced cytidine deaminase (AID) is mutagenic and has been implicated in human tumorigenesis. Helicobacter pylori infection of gastric epithelial cells leads to aberrant expression of AID and somatic gene mutations. We investigated whether AID induces genetic aberrations at specific chromosomal loci that encode tumor-related proteins in gastric epithelial cells.
METHODS: Human gastric epithelial cell lines that express activated AID and gastric cells from AID transgenic mice were examined for DNA copy number changes and nucleotide alterations. Copy number aberrations in stomach cells of H pylori-infected mice and gastric tissues (normal and tumor) from H pylori-positive patients were also analyzed.
RESULTS: In human gastric cells, aberrant AID activity induced copy number changes at various chromosomal loci. In AID-expressing cells and gastric mucosa of AID transgenic mice, point mutations and reductions in copy number were observed frequently in the tumor suppressor genes CDKN2A and CDKN2B. Oral infection of wild-type mice with H pylori reduced the copy number of the Cdkn2b-Cdkn2a locus, whereas no such changes were observed in the gastric mucosa of H pylori-infected AID-deficient mice. In human samples, the relative copy numbers of CDKN2A and CDKN2B were reduced in a subset of gastric cancer tissues compared with the surrounding noncancerous region.
CONCLUSIONS: H pylori infection leads to aberrant expression of AID and might be a mechanism of the accumulation of submicroscopic deletions and somatic mutations in gastric epithelial cells. AID-mediated genotoxic effects appear to occur frequently at the CDKN2b-CDKN2a locus and contribute to malignant transformation of the gastric mucosa.
Authors:
Yuko Matsumoto; Hiroyuki Marusawa; Kazuo Kinoshita; Yoko Niwa; Yoshiharu Sakai; Tsutomu Chiba
Related Documents :
4074557 - Ocular involvement in the acquired immune deficiency syndrome (aids).
21585497 - Specialization effect and its influence on memory and problem solving in expert chess p...
1418187 - Status and trend of hiv-1 infection and aids in taiwan, december, 1991.
3006817 - Aids and haemophilia.
12612097 - Community participation in a multisectoral intervention to address health determinants ...
21856717 - An item response theory analysis of the problem gambling severity index.
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't     Date:  2010-07-14
Journal Detail:
Title:  Gastroenterology     Volume:  139     ISSN:  1528-0012     ISO Abbreviation:  Gastroenterology     Publication Date:  2010 Dec 
Date Detail:
Created Date:  2010-12-03     Completed Date:  2011-01-04     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0374630     Medline TA:  Gastroenterology     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1984-94     Citation Subset:  AIM; IM    
Copyright Information:
Copyright © 2010 AGA Institute. Published by Elsevier Inc. All rights reserved.
Affiliation:
Department of Gastroenterology and Hepatology, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Cell Line
Cell Transformation, Neoplastic / metabolism,  pathology
Chromosome Aberrations
Cyclin-Dependent Kinase Inhibitor p15 / genetics*,  metabolism
Cyclin-Dependent Kinase Inhibitor p16 / genetics*,  metabolism
Cytidine Deaminase / genetics*,  metabolism
Epithelial Cells / enzymology*,  microbiology,  pathology*
Gene Dosage
Gene Expression Regulation, Enzymologic / physiology
Gene Expression Regulation, Neoplastic / physiology
Helicobacter Infections / genetics,  metabolism,  pathology
Helicobacter pylori
Humans
Mice
Mice, Inbred C57BL
Mice, Transgenic
Stomach / pathology
Stomach Neoplasms* / genetics,  metabolism,  pathology
Up-Regulation / physiology
Chemical
Reg. No./Substance:
0/CDKN2B protein, human; 0/Cdkn2a protein, mouse; 0/Cdkn2b protein, mouse; 0/Cyclin-Dependent Kinase Inhibitor p15; 0/Cyclin-Dependent Kinase Inhibitor p16; EC 3.5.4.5/Cytidine Deaminase

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Babesia gibsoni: detection in blood smears and formalin-fixed, paraffin-embedded tissues using deoxy...
Next Document:  Association of host mitochondria with the parasitophorous vacuole during Toxoplasma infection is not...