Figure 1. Multifaceted role of IFN-γ in cancer.

Pro-tumor function of IFN-γ is mediated by chronic inflammation involving inflammatory monocytes and macrophages. Anti-tumor function of IFN-γ is mediated by cells of the adaptive immune system (CTL and Th1), NK cells and NKT cells. The outcome of anti-tumor immune responses is determined by the status of the expression of IFN-γ Rα on target cells such that high levels of IFN-γ Rα render the tumor susceptible to apoptosis while low levels of IFN-γ Rα could result in tumor immunoediting and relapse or maintenance of immunogenic tumor dormancy depending on the type of tumor dormancy being Ki67^- quiescent or Ki67^low indolent, respectively.