The resulting IL-2 would enhance the differentiation of naive T cells into iTregs with high levels of granzyme B. Intriguingly, Tregs could express IL-3 themselves in response to TGF-β, which would further increase the concentration of IL-2 in TME and forms a self-feeding loop to stall anti-tumor immunity (106). This evidence concerns the gene TGFB1 and neoplasm.