AP-1 is induced by DCA at concentrations found in Barrett's oesophagus. SKGT4 cells were treated with DCA over a concentration range of 0 – 500 μM for 6 hr. Total cell lysates were prepared and standardized to 350 μg. DNA affinity purification was performed and proteins were resolved by SDS-PAGE and immunoblotted with anti-Fra-1 or anti-JunB, respectively. Unbound proteins were immunoblotted with anti-α-tubulin as loading control. Results are representative of at least three independent experiments.