IFNG and neoplasm: In the colorectal cancer microenvironment, tumor-infiltrating effector T cells and natural killer cells are the primary sources of IFN-γ, with secondary sources including Foxp3+ CD4+ regulatory T cells (Tregs), Th17 cells, Th22 cells, NKT cells, innate lymphoid cells (ILCs), and certain antigen-presenting cells (178).