Cdx2 ectopic expression induces gastric intestinal metaplasia in transgenic mice.
OBJECTIVE
Intestinal-type gastric cancer is often preceded by intestinal metaplasia in humans. The genetic events responsible for the transdifferentiation that occurs in intestinal metaplasia are not well understood. Cdx2, a transcription factor whose expression is normally limited to the intestine, has been detected in gastric intestinal metaplasia. Cdx2 induces differentiation of intestinal epithelial cells in vitro; therefore, we sought to establish whether a causal relationship exists between Cdx2 activation and intestinal metaplasia.


METHODS
Cdx2 expression was directed to the gastric mucosa in transgenic mice using cis-regulatory elements of Foxa3 (Hnf3gamma). Transgenic mice were analyzed for histologic and gene expression changes.


RESULTS
Histologic examination of the gastric mucosa of the Foxa3/Cdx2 mice revealed the presence of alcian blue-positive intestinal-type goblet cells, a hallmark of intestinal metaplasia. In addition, Cdx2 induced the expression of intestine-specific genes.


CONCLUSIONS
Gastric expression of Cdx2 alone was sufficient to induce intestinal metaplasia in mice. These mice represent a powerful tool to investigate the molecular mechanisms that promote intestinal metaplasia. Moreover, as gastric cancer in humans is often preceded by intestinal metaplasia, the phenotype described here strongly suggests involvement of Cdx2 in the initiation of the process leading to intestinal neoplasia of the gastric mucosa.
Silberg
Debra G
DG
Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104, USA. silberg@mail.med.upenn.edu
Sullivan
Jessica
J
Kang
Eugene
E
Swain
Gary P
GP
Moffett
Jennifer
J
Sund
Newman J
NJ
Sackett
Sara D
SD
Kaestner
Klaus H
KH
D000818:Animals; D000071616:CDX2 Transcription Factor; D002454:Cell Differentiation / Q000502:physiology; D018244:Chromosomes, Artificial, Yeast; D004268:DNA-Binding Proteins / Q000235:genetics; D005753:Gastric Mucosa / Q000473:pathology*; D015972:Gene Expression Regulation, Neoplastic; D051543:Hepatocyte Nuclear Factor 3-gamma; D018398:Homeodomain Proteins / Q000235:genetics*; D007413:Intestinal Mucosa / Q000473:pathology*; D008679:Metaplasia / Q000473:pathology; D051379:Mice; D008822:Mice, Transgenic; D009687:Nuclear Proteins / Q000235:genetics; D011230:Precancerous Conditions / Q000473:pathology; D015534:Trans-Activators; D014157:Transcription Factors
D000071616:CDX2 Transcription Factor; D004268:DNA-Binding Proteins; C496506:Foxa3 protein, mouse; D018398:Homeodomain Proteins; D009687:Nuclear Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D051543:Hepatocyte Nuclear Factor 3-gamma