MUC2 and Barrett esophagus: To determine whether KLF5 induction by bile acids occurs during the development of BE, Het-1A cells were exposed to 200 μM DCA for 2, 4, 8 or 12 hours, and examination of effects on the expression of the transcription factor KLF5 at the mRNA and protein levels confirmed that KLF5 expression was augmented by exposure to 200 μM DCA in a time-dependent manner; the intestinal markers Cdx2, MUC2 and villin were also up-regulated simultaneously (Fig. 3).