IL-12 gene therapy for cancer: in synergy with other immunotherapies.

In preclinical models of cancer, gene therapy with interleukin 12 (IL-12) has reached unprecedented levels of success when combined with immunotherapy approaches such as gene transfer of other cytokines and/or chemokines, costimulatory molecules or adoptive cell therapy. These combinations have been found to produce synergistic rather than additive effects. Meanwhile, IL-12 gene therapy is beginning clinical testing as a single agent, but combination strategies are at hand.