Immunological battlefield in gastric cancer and role of immunotherapies

Figure 2 Two different tumour microenvironments of different molecular subgroups of gastric cancer. A: Example of a strong immunogenic tumour with increased antigen presentation and immune checkpoints expression, more TILs and other effector immune cells infiltration into the tumour; B: Example of a weak anti-tumour immune response with less antigen expression, less TILs and other effector immune cell infiltration into tumour and increased numbers of immunosuppressive cells; C: Schematic diagram representing poor defences from a conspicuous tumour with vigorous immune response; D: Schematic diagram representing good defences from a less conspicuous tumour with minimal immune response. MDSC: Myeloid-derived suppressor cell; TAM: Tumour associate macrophages; Treg: T regulatory cell; Th17: T helper cell-17; ECM: Extracellular matrix; MHC: Major histocompatibility complex; TCR: T-cell receptor.