IL33 and head and neck squamous cell carcinoma: Infiltrated ST2-expressing Tregs were responsive to IL-33, and the percentage of Tregs was increased upon IL-33 stimulation, in particular Foxp3+GATA3+ Tregs, which enhanced the suppressive functions of Tregs by inducing IL-10 and TGF-β1 and decreasing the proliferation of responder T cells in head and neck squamous cell carcinoma [122, 123].