IFNG and neoplasm: In general, resistance to immunotherapy is caused by insufficient tumor antigenicity due to the lack of tumor neoantigens, defects in transduction of anti-tumor immune response mediated by tumor-intrinsic IFNγ signaling, impaired antigen processing and presentation machinery, regulation by oncogenic signaling, and tumor dedifferentiation and stemness (Sharma et al., 2017; Draghi et al., 2019; Kalbasi and Ribas, 2020; Schoenfeld and Hellmann, 2020).