IFNG and cancer: Additional functions of IFN-γ include the upregulation of major histocompatibility complex (MHC) class I and II molecules, which favors the priming of antigen-specific cytotoxic T lymphocytes (Castro et al., 2018; Schoenborn and Wilson, 2007), and also the activation and differentiation of cytotoxic T cells that promote cancer cell death (Zaidi and Merlino, 2011; Martinez-Lostao et al., 2015; Miller et al., 2009).