Changes in gene expression of neo-squamous mucosa after endoscopic treatment for dysplastic Barrett's esophagus and intramucosal adenocarcinoma.

Levert-Mignon, Angelique; Bourke, Michael J; Lord, Sarah J; Taylor, Andrew C; Wettstein, Antony R; Edwards, Melanie; Botelho, Natalia K; Sonson, Rebecca; Jayasekera, Chatura; Fisher, Oliver M; Thomas, Melissa L; Macrae, Finlay; Hussey, Damian J; Watson, David I; Lord, Reginald V

BACKGROUND Endoscopic therapy, including by radiofrequency ablation (RFA) or endoscopic mucosal resection (EMR), is first line treatment for Barrett's esophagus (BE) with high-grade dysplasia (HGD) or intramucosal cancer (IMC) and may be appropriate for some patients with low-grade dysplasia (LGD). OBJECTIVE The purpose of this study was to investigate the molecular effects of endotherapy. METHODS mRNA expression of 16 genes significantly associated with different BE stages was measured in paired pre-treatment BE tissues and post-treatment neo-squamous biopsies from 36 patients treated by RFA (19 patients, 3 IMC, 4 HGD, 12 LGD) or EMR (17 patients, 4 IMC, 13 HGD). EMR was performed prior to RFA in eight patients. Normal squamous esophageal tissues were from 20 control individuals. RESULTS Endoscopic therapy resulted in significant change towards the normal squamous expression profile for all genes. The neo-squamous expression profile was significantly different to the normal control profile for 11 of 16 genes. CONCLUSION Endotherapy results in marked changes in mRNA expression, with replacement of the disordered BE dysplasia or IMC profile with a more "normal" profile. The neo-squamous mucosa was significantly different to the normal control squamous mucosa for most genes. The significance of this finding is uncertain but it may support continued endoscopic surveillance after successful endotherapy.