Identification of genes modulated by acid and bile in a Barrett's oesophagus cell line

ABSTRACT: The major aetiological risk factor for Barrett's oesophagus and oesophageal adenocarcinoma is gastroesophageal reflux. This study's aim was to identify genes involved in the celular response to reflux in vitro. The Barrett’s oesophagus cell line, CP-A hTERT, was exposed to media with acid, deoxycholic acid or a primary bile salt mixture. RNA expression was compared with controls on Affymetrix U133 Plus 2.0 arrays. In CP-A hTERT, the greatest number of changes in gene expression was observed after treatment with deoxycholic acid, pH 4.5; 152 genes were up-regulated at 2 hours (91 at 6 hours) and 10 down-regulated at 2 hours (34 at 6 hours). 12 genes were identified and were subsequently assessed in patients with non-erosive reflux disease, oesophagitis, Barrett's oesophagus and oesophageal adenocarcinoma Background and Aims: The major etiological risk factor for Barrett’s esophagus and esophageal adenocarcinoma is gastro-esophageal reflux. This study’s aim was to identify genes involved in the cellular response to components of reflux both in vitro and in patients with reflux-related disease. Methods: The Barrett’s cell line, CP-A hTERT, was exposed to media with acid, deoxycholic acid or a primary bile salt mixture. RNA expression was compared with controls on Affymetrix U133 Plus 2.0 arrays. 12 genes of interest were analysed by Real Time PCR both in cell line and biopsies from 110 patients with non-erosive reflux disease, esophagitis, Barrett’s esophagus and esophageal adenocarcinoma. Results: In CP-A hTERT, the greatest number of changes in gene expression was observed after treatment with deoxycholic acid, pH 4.5. Of 12 genes analysed in biopsies, 10 were significantly different between the 4 groups with the largest change for anterior gradient homolog 2, which may modulate p53 function. This had highest expression in biopsies from Barrett’s esophagus (median gene fold change for Barrett’s esophagus versus non-erosive reflux disease, 411.2 (95% CI 290.5-682.7; p<0.01); esophageal adenocarcinoma versus non-erosive reflux disease 68.1 (20.5-161.4; p<0.01)). In addition 4 genes associated with development/differentiation were upregulated in Barrett’s biopsies compared to those from non-erosive reflux disease (SEL1L, MFNG, CRIP1 and EFNA1). Conclusions: Novel genes have been identified, whose expression is altered after acid and bile exposure in vitro and in biopsies from patients with reflux related diseases. These genes may have utility as biomarkers of response to reflux and should be assessed in prospective studies. Keywords: Acid (pH 4.5) and bile (mixture of primary bile salts or the secondary bile salt deoxycholic acid, both at pH 4.5) challenge to a Barrett's oesophagus cell line. RNA extraction at 2 and 6 hours. Comparison of treatment RNA to control (non-treatment) RNA,

ORGANISM(S): Homo sapiens

PROVIDER: GSE9768 | GEO | 2007/12/05

SECONDARY ACCESSION(S): PRJNA103703

REPOSITORIES: GEO