Interleukin-12 as an in situ cancer vaccine component: a review

Interleukin-12 (IL-12) is a type I cytokine involved in both innate and adaptive immunity that stimulates T and natural killer cell activity and induces interferon gamma production. IL-12 has been identified as a potential immunotherapeutic component for combinatorial cancer treatments. While IL-12 has successfully been used to treat a variety of cancers in mice, it was associated with toxicity when administered systemically in cancer patients. In this review, we discuss the research findings and progress of IL-12 used in combination with other cancer treatment modalities. We describe different methods of IL-12 delivery, both systemic and local, and ultimately highlight the potential of an in situ vaccination approach for minimizing toxicities and providing antitumor efficacy. This review offers a basis for pursuing an in situ vaccine approach that may eventually allow IL-12 to be more readily integrated as an immunotherapy into the clinical treatment of cancers.