Interestingly, upon subclustering of Tregs based on CCR4 expression (Supplementary Figure 7C), CCR4+ Tregs were more enriched with gene sets associated with tumor immune evasion and response to immune checkpoint (IC) blockade (Supplementary Figure 7D), suggesting that CCR4+ Tregs possess a regulatory program that could become clinically relevant under pathological conditions such as cancer (51, 52). Here, CCR4 is linked to cancer.