PDCD1 and cancer: The blockade of TIM-3 or galectin-9 in MMTV-PyMT tumour-bearing mice increases the expression of CXC chemokine ligand 9 (CXCL9) in CD103+ dendritic cells, which recruits cytotoxic CXC chemokine receptor 3 (CXCR3)+ CD8+ T cells to tumours.15 Given the importance of TIM-3-expressing T cells and dendritic cells in cancer progression and chemotherapy response, TIM-3 inhibition might be useful in the metastatic setting to recruit cytotoxic T cells or to reinvigorate exhausted T cells in immunotherapy-naïve and/or anti-PD-1 refractory patients.