CXCL9 and CXCL10 can be produced by antigen-presenting cells (dendritic cells or macrophages) and by tumor cells. Hoch et al. demonstrated that CXCL9 and CXCL10 co-localize with LAG3+ T cells expressing CCL4 or CXCL13 and contribute to the generation of a "hot" tumor microenvironment.