While KIR+CD8+ Tregs have been described to target antigen-specific CD4+ T cells through interactions between both classical and non-classical major histocompatibility complex interactions in autoimmunity2,19 and one prior study reported that the interactions between FOXP3−CD8+CD25+KIR+CD127– and CD4+ Tregs were important in influencing anti-tumor immunity3, we observed no association between the frequency of KIR+CD8+ T cells and CD4+ T cell subsets in the tumor microenvironment (data not shown). Here, CD4 is linked to neoplasm.