Here, we define a facet of the multiple potential functionalities of TSLP in modulating melanoma-associated immune responses, showing that keratinocyte-derived TSLP is crucial for the accumulation of Tregs — or, more specifically, GATA3+ Tregs — in both tumor-draining LNs and cutaneous tumor sites, reminiscent of “tumor-associated Treg” identified by several studies in various tumors in mice and humans (33–37). Here, TSLP is linked to neoplasm.