Lastly, single-cell mRNA datasets from NPC samples indicated that CD4 mRNA was expressed by monocytes/macrophages, DCs, and T cells, Fibronectin/FN1 was expressed by fibroblasts and monocytes/macrophages, while CD11c/ITGAX and IDO1 were expressed mainly by myeloid cells. This evidence concerns the gene IDO1 and nasopharyngeal carcinoma.