It is worth noting that MLE (which can also be a feature of normal rat mucosa) might be considered as a “”partially-committed”" cell population, prone to a chimeric intestinal differentiation under critical conditions (such as those produced by EGDA). Such speculations might also apply to the staminal cells compartment of the native esophageal mucosa: in cultured esophageal epithelia, in fact, chemical injuries (acid and/or bile components) may result in Cdx2 promoter demethylation/activation

Selleckchem BAY 80-6946 [33]. These hypotheses are further supported by the finding that no Cdx2 expression was detected in squamous epithelia (far from esophageal ulcers/metaplastic changes), nor in any of the 4 cases of SCC. Together with Cdx2, also other intestine-specific transcription factors have been described as involved in Barrett’s epithelium development [34–36]. In a similar rat model, Kazumori et al. [36] showed, that a de novo expression

of Cdx1 (another member of the caudal-related homeobox gene family) significantly antecedes Cdx2 expression [35, 36]. Further studies are needed to investigate on the interplay www.selleckchem.com/products/Deforolimus.html of these two genes in the morphogenesis of Barrett’s mucosa. The SCC cases detected in this study prompts us to hypothesize that the environmental conditions resulting from EGDA may also result into the derangement of cell regulatory mechanisms involving both multilayered and squamous epithelia. Previous studies documented that several transcription factors (p63, among others) are over-expressed in squamous esophageal epithelia after EGDA. Such an observation could explain, at least in part,

the high prevalence of SCC documented in this and other studies. Conclusion In conclusion, the Kumagai-Hattori model of esophago-gastroduodenal anastomosis (with gastric preservation) is an useful in vivo model of esophageal carcinogenesis. Both the stem cell compartment and Casein kinase 1 the multilayered epithelium are early involved in the metaplastic intestinalization of the native esophageal mucosa. Acknowledgements The authors are grateful to Cristiano Lanza and Vanni Lazzarin for their technical assistance. This work has been partially supported by a “”G. Berlucchi”" Foundation grant. References 1. Chawengsaksophak K, de Graaff W, Rossant J, Deschamps J, Beck F: Cdx2 is essential for axial elongation in mouse development. PNAS 2004, 101: 7641–7645.CrossRefPubMed 2. Groisman GM, Amar M, Meir A: Expression of the intestinal marker Cdx2 in the columnar-lined esophagus with and without intestinal (Barrett’s) metaplasia. Modern Pathol 2004, 17: 1282–1288.CrossRef 3. Moons LM, Bax DA, Kuipers EJ, Van Dekken H, Haringsma J, Van Vliet AH, Siersema PD, Kusters JG: The homeodomain protein CDX2 is an early marker of Barrett’s esophagus. J Clin Pathol 2004, 57: 1063–1068.CrossRefPubMed 4.