Elevated levels of CXCL9 and CXCL10 are associated with an increased number of tumour‐infiltrating CD8‐positive T cells, decreased cancer metastasis and increased survival of cancer patients.32, 33 Experiments on CXCR3 knockout mice bearing B16 melanoma demonstrated a critical role for CXCR3 in the migration of CD8‐positive cells. This evidence concerns the gene CXCL9 and cancer.