Ad-mda7-mediated tumor growth inhibition is due to MDA-7 protein expression. Tissue lysates prepared from PBS-treated, Ad-luc-treated, and Ad-mda7-treated subcutaneous tumors were subjected to western blotting and detected for MDA-7 protein. Exogenous MDA-7 protein expression was detected in Ad-mda7-treated tumor tissue lysates but not PBS-treated tumor lysates. A non-specific band in one sample of Ad-luc-treated tumor lysate was observed. β-actin was used as a loading control.