IL-12-based therapy of malignancies

Interleukin-12 (IL-12) is an important molecule that triggers the activation of natural killer (NK) cells and T-cells, the development of T helper type 1 (Th1) cells and the expression of antiangiogenic genes. Novel methods for IL-12 delivery include cell-based ex vivo gene therapy, viral vector-based gene therapy and DNA plasmid-based nonviral gene therapy. IL-12 electroporation gene therapy may hold some promise for tumors accessible by electrode, such as head and neck cancer, breast cancer, prostate cancer and melanoma. Codelivery of other therapeutic genes with IL-12 may enhance the therapeutic effect and reduce the level of IL-12 required for efficacy. All three approaches to IL-12 gene therapy are under clinical investigation. The preliminary results indicate that IL-12 gene therapy is safe and is not associated with any major clinical toxicity.