FOXO4 and head and neck squamous cell carcinoma: In this study, we found STAT1 of Th1 cells, STAT6 of Th2 cells, BCL6 of Tfh cells, STAT3 of Th17 cells, FOXP3, CCR8, CD25 (IL-2R) and STAT5B of Tregs, IRF4 of Th9 cells, FOXO4,CD196 (CCR6) and CD194 (CCR4) of Th22 cells are significantly correlated with YTHDC2 expression in HNSCC.