title: CDX2 in congenital gut gastric-type heteroplasia and intestinal-type Meckel diverticula.
abstract: The mechanisms that determine organ identity along the digestive tract in humans are poorly understood. Here we describe the rare case of a young patient who presented with congenital gastric-type heteroplasia in the midjejunum. The lesions, located along the antimesenteric midline of the gut, were made of histologically and functionally normal gastric epithelium without inflammation or in situ/invasive carcinoma. They resembled the anatomy of the lesions developing in the mouse gut as a result of haploinsufficiency of the Cdx2 homeobox gene. The lesions were devoid of CDX2 but without mutation in the coding sequence or in a cis-regulatory element required for intestine-specific expression. Combining these data with the CDX2 expression pattern established from human embryos and cases of Meckel diverticula, we propose a scenario for this patient's presentation, in which CDX2 was missing at the site of ventral closure during gut morphogenesis, with subsequent default differentiation into gastric instead of intestinal tissue. Altogether, these observations argue in favor of a pivotal role played by CDX2 in determining intestinal identity during human embryonic development, as previously shown experimentally in mice.
authors.affiliation: INSERM U682, 3 Avenue Molière, 67200 Strasbourg, France.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Martin
authors.forename: Marie
authors.initials: M
authors.lastname: Vanier
authors.forename: Manuela
authors.initials: M
authors.lastname: Tavian
authors.forename: Eric
authors.initials: E
authors.lastname: Guerin
authors.forename: Claire
authors.initials: C
authors.lastname: Domon-Dell
authors.forename: Isabelle
authors.initials: I
authors.lastname: Duluc
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gross
authors.forename: Jonathan
authors.initials: J
authors.lastname: Rowland
authors.forename: Sunghoon
authors.initials: S
authors.lastname: Kim
authors.forename: Jean-Noël
authors.initials: JN
authors.lastname: Freund
mesh_terms: D000071616:CDX2 Transcription Factor; D002648:Child; D018398:Homeodomain Proteins / Q000502:physiology*; D006801:Humans; D008297:Male; D008467:Meckel Diverticulum / Q000209:etiology* / Q000473:pathology*
chemical_list: D000071616:CDX2 Transcription Factor; C491270:CDX2 protein, human; D018398:Homeodomain Proteins