Charaterization of a variety of genomic defects in malignant cells (1) has led to attempts to treat cancer by gene therapy. Gene therapy is a therapeutic approach in which therapeutic nucleic acids are transferred into the affected organs. Although the ideal concept would be the replacement of the abnormal gene by a copy of the functional gene, currently there have not been reliable and safe techniques to allow the site-specific integration of DNA into the human genome (2). Thus, almost all gene therapies are developed by simply transferring the therapeutic gene into somatic cells without replacing the abnormal gene. The goal is to identify and correct genetic abnormalities interfering with the cell cycle and to correct them in all cells. Technically, there are two methods amenable for gene transfer: reintroduction of in vitro transferred gene into the body and direct transfer of gene into the target cells in vivo.