Mutation in the p53 gene is the most frequently found genetic abnormality in human tumors, resulting in increased resistance to chemo- and radiotherapy (1 ,2 ). The underlying rationale for p53 -mediated cancer gene therapy is to restore the ability of p53 mutant tumors to undergo apoptosis. When the wild-type p53 gene is delivered into tumor cells of various origins by adenoviral vector, the cells become more sensitive to cisplatin and radiation therapy (3 ). In addition, adenovirus expressing p53 is a great laboratory tool for the determination of function, for conveniently producing large quantities of p53 protein, and for determining the effect of p53 on cellular gene expression using microarray technology (4 ).