The tumour microenvironment plays a role in the cancer immunity cycle

The multicellular composition of the tumour microenvironment includes1:

  • Tumour cells: malignant cells that are both aided by and influence the makeup of the tumour microenvironment to ensure growth and survival2,3
  • Tumour-infiltrating immune cells: lymphoid and myeloid cells, which can stimulate or inhibit the antitumour immune response2,3
  • Stromal cells: tumour-associated fibroblasts and endothelial cells that contribute to the tumour’s structural integrity1

The multicellular composition of the tumor microenvironment includes1:

  • Tumour cells: malignant cells that are both aided by and influence the makeup of the tumour microenvironment to ensure growth and survival2,3
  • Tumour-infiltrating immune cells: lymphoid and myeloid cells, which can stimulate or inhibit the antitumour immune response2,3
  • Stromal cells: tumour-associated fibroblasts and endothelial cells that contribute to the tumour’s structural integrity1

Lymphocytes

T cell lymphocyte image

T cells

T cells

Antigen-specific immune cells that carry out cell-mediated adaptive immune responses following activation by dendritic cells. Includes CD8 T cells (cytotoxic T cells) and CD4 T cells4,5

B cells

Antigen-specific immune cells that produce antibodies during an immune response5

B cell lymphocyte image

B cells

Antigen-specific immune cells that produce antibodies during an immune response5

Natural killer cell lymphocyte image

Natural killer (NK) cells

Natural killer (NK) cells

Cytotoxic lymphocytes that recognize and kill stressed or malignant cells independent of antigen specificity (unlike T and B cells)3

Myeloid Cells

Dendritic cells (DCs)

Antigen-presenting cells that capture and process cancer antigens to initiate an immune response6

Myeloid-derived suppressor cell image

Dendritic cells (DCs)

Antigen-presenting cells that capture and process cancer antigens to initiate an immune response6

Macrophage myeloid cell image

Macrophages

Macrophages

Type of phagocyte that detects pathogens, secretes cytokines, and presents antigens. Includes

  • M1 macrophages, which promote inflammation and antitumour responses3,7
  • M2 macrophages, which reduce inflammation and produce factors that can promote tumour growth3,7

Myeloid-derived suppressor cells (MDSCs)

Immature myeloid cells, including DC and macrophage precursors, which have potent immunosuppressive activity on T-cell function8

Myeloid-derived suppressor cell image

Myeloid-derived suppressor cells (MDSCs)

Immature myeloid cells, including DC and macrophage precursors, which have potent immunosuppressive activity on T-cell function8

cancer tumour microenvironment cancer tumour microenvironment cancer tumour microenvironment