In addition, tumour cells can release a variety of cytokines and chemicals such as IL‐10, TGF‐β, PGE2 and IDO to induce apoptosis in CD8+ T cells, and these cytokines and chemicals may induce apoptosis in CD8+ T cells through a variety of signalling pathways and routes [36]. This evidence concerns the gene TGFB1 and neoplasm.