The observation that CCR8+ Tconv cells expand and undergo activation to express IL-10 following depletion of Treg cells provides an explanation of how bulk Tconv cells from tumors of Treg cell-depleted animals acquire IL-10-dependent suppressive function despite lack of a change in the relative frequency of CCR8+ cells within the tumor CD4+ Tconv compartment. This evidence concerns the gene CCR8 and neoplasm.