• Department of Gastroenterology, Hepatology and Nutrition, The University of Texas MD Anderson Cancer Center, Houston, TX, USA. rbresali@mdanderson.org.
• Center for Esophageal Diseases and Swallowing, The University of North Carolina, Chapel Hill, NC, USA.
• Department of Biostatistics, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Boulevard Unit 1466, Houston, TX, 77030, USA.
• Department of Gastroenterology, Mayo Clinic, Rochester, MN, USA.
• Department of Gastroenterology, St. Michael's Hospital, Toronto, Canada.
• Department of Gastroenterology, University of Colorado, Aurora, CO, USA.
• Department of Gastroenterology, University of California, Los Angeles, CA, USA.
• Department of Gastroenterology, University of Pennsylvania, Philadelphia, PA, USA.
• Department of Gastroenterology, Hepatology and Nutrition, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
• Department of Palliative, Rehabilitation and Integrative Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.

OBJECTIVES/METHODS: Placebo-controlled phase II study evaluated aspirin's effect on CDX2 mRNA and prostanoid production in native and neosquamous epithelium after successful radiofrequency ablation (RFA) in Barrett's esophagus.

RESULTS: At 12 months TXB2, PGF2α, PGD2, PGE2, PGE1, and α13PGE2 increased in native squamous but not neosquamous epithelium in individuals randomized to placebo. Aspirin use significantly reduced CDX2 mRNA in native squamous epithelium, and was associated with decreases in PGE1, PGE2 and 13PGE2 in neosquamous epithelium.

CONCLUSIONS: After RFA, native squamous and neosquamous epithelium exhibit different molecular markers and responses to aspirin suggesting that different sources of squamous progenitors contribute to esophageal re-epithelization.