Activation of the BMP4 Pathway and Early Expression of CDX2 Characterize Non-specialized Columnar Metaplasia in a Human Model of Barrett’s Esophagus.
J Gastrointest Surg. 2011 Nov 11;
Authors: Castillo D, Puig S, Iglesias M, Seoane A, de Bolós C, Munitiz V, Parrilla P, Comerma L, Poulsom R, Krishnadath KK, Grande L, Pera M
Abstract
BACKGROUND: A human model of gastroesophageal reflux disease was used to examine the contribution of a non-specialized columnar type of metaplasia (NSCM) and key molecular events (BMP4 and CDX2) in the development of Barrett’s esophagus. METHODS: Biopsies of the remnant esophagus from 18 patients undergoing esophagectomy with gastric preservation were taken at 6-36-month intervals postoperatively and examined for activation of the BMP pathway (BMP4/P-Smad 1/5/8) and CDX2 and CDX1 expression by imunohistochemistry, quantitative real-time PCR, Western blot, and in situ hybridization. RESULTS: A short segment (mean 15.6 mm) of NSCM was detected in 10 (56%) patients, with an increasing prevalence from 17% at 6 months to 62% at 36 months. Nuclear expression of P-Smad 1/5/8 in the squamous epithelium close to the anastomosis with strong expression in all epithelial cells of NSCM areas was found. Forty-eight (63%) biopsies with NSCM showed scattered nuclear expression of CDX2. Two cases showed isolated glands at 18, 24, and 36 months that fully expressed CDX2 and co-expressed CDX1. BMP4 mRNA and CDX2 mRNA levels were significantly greater in NSCM than in squamous epithelium. CONCLUSIONS: BMP4 activation in NSCM and early expression of CDX2 are involved in the columnar epithelial differentiation of Barrett’s esophagus.
PMID: 22076569 [PubMed - as supplied by publisher]