Cytokine gene therapy: A new strategy for the management of cancer patients

Cytokine gene therapy has recently become a new potential prospect in the management of cancer patients. This has stemmed from clinical considerations based on the evidence that high-dose interleukin-2 (IL-2) may be effective in a proportion of patients, that foreign genetic material may be successfully inserted into the genome of normal and neoplastic cells, and by extensive studies in experimental models which have shown that cytokine-gene-transduced tumor cells may reveal a diminished or abolished tumorigenicity. Evidence has also been provided that the IL-2 released constitutively by engineered tumor cells may induce the generation of specific cytotoxic T lymphocytes and of an antitumor memory response. Here, we will review the data which have led to the activation of the first pilot vaccination protocols with IL-2 gene-transduced allogeneic cell lines for advanced-stage melanoma and renal cell carcinoma patients. New directions in delivery modalities, as well as future strategies will also be discussed.