MDA-MB-231 cells were incubated at 37°C for 6h with vehicle control (0 µM) and 100 µM of esomeprazole sodium (ab120500). Increased expression of aryl hydrocarbon receptor (ab2770) correlates with an increase in esomeprazole sodium concentration, as described in literature.Whole cell lysates were prepared with RIPA buffer (containing protease inhibitors and sodium orthovanadate), 20µg of each were loaded on the gel and the WB was run under reducing conditions. After transfer the membrane was blocked for an hour using 3% milk before being incubated with ab2770 at 2 µg/ml and ab8226 at 1 µg/ml overnight at 4°C. Antibody binding was detected using an anti-mouse antibody conjugated to HRP (ab97040) at 1/10000 dilution and visualised using ECL development solution.