T lymphocytes are activated to secrete IFNγ, subsequently, high local concentrations of IFNγ and TNFα secreted by tumor-associated macrophages induce cancer cells to express programmed death ligand 1, which specifically binds PD-1 and initiates T lymphocyte apoptosis, thereby enabling cancer cells to achieve immune escape [101,102]. This evidence concerns the gene IFNG and neoplasm.