Recent developments in gene-directed enzyme prodrug therapy (GDEPT) for cancer.

ABSTRACT

Gene-directed enzyme prodrug therapy (GDEPT) is a promising two-step treatment for solid malignant tumors. In the first step, the gene for a foreign enzyme is administered and directed to the tumor, where it may be expressed using specific transcriptional elements. In the second step, prodrugs are administered and activated by the foreign enzyme expressed at the tumor. This review focuses on the progress from the end of 1997 to date. Important issues, such as viral and non-viral vectors, new enzyme/prodrug systems, new strategies, advances in the understanding of the bystander effects, the comparison of different systems used in GDEPT and clinical trials are outlined.