Interleukin 12: Basic Biology and Potential Applications in Cancer Treatment

Interleukin 12 is a heterodimeric cytokine that has potent effects on innate and adaptive immunity. Interleukin 12 induces interferon g secretion by T cells and natural killer cells, enhances the proliferation of activated T cells and natural killer cells, augments the cytolytic activity of cytotoxic T lymphocytes and natural killer cells, and supports the differentiation of Th1 helper effector cells. Interleukin 12 stimulates in vitro antitumor activity of lymphocytes from patients with cancer and in vivo antitumor activity in many murine tumor models. Current data indicate that CD4 T cells, CD8 T cells, natural killer cells and interferon g may contribute to the antitumor effects of interleukin 12 therapy. However, further investigation is required to elucidate the precise mechanisms involved in the antitumor activity of interleukin 12.