CTLA4 and neoplasm: Th17 cells have also been associated with tumor progression in oral cancer (39), as well as Tregs, which have been found increased not only in the oral tissue, but also in peripheral blood (40, 41), expressing CTLA-4+, HLA-DR+ and granzyme B+ (42) and inhibiting IFN-γ, and promoting IL-10 and TGF-β secretion (43, 44).