Recent studies of melanoma model mice and the TCGA melanoma dataset have shown that infiltration of cDC1 in the tumor is induced by XCL1, CCL5, or FMS-like tyrosine kinase 3 ligand (FLT3LG), which are produced by the NK cells infiltrated in the tumor (Figure 2) [22,23]. The gene discussed is MPPE1; the disease is neoplasm.