In addition, a cluster of CD83+CCR7+LAMP3+ DCs was found in OS and can be referred to as mature regulatory DCs (mregDCs) (Fig. 2a–c).16 To investigate whether these mregDCs are tumor specific, we aggregated the DCs from normal peripheral blood mononuclear cells (PBMCs) (GSE94820) and two OS cohorts (GSE152048 and GSE162454) through Harmony packages (Fig. 2d).17 We found that mregDCs preferentially existed in the two independent OS cohorts but were nearly absent in normal PBMCs, indicating that mregDCs may be a tumor-associated DC population (Fig. 2d, e). Here, CCR7 is linked to neoplasm.