Media conditioned by HNSCC tissues skewed CD4+ cells toward increased expression of the Treg marker Foxp3 (8.97 ± 0.63), but supplementation of HNSCC-conditioned media with recombinant IL-23 prevented the Foxp3 expression (0.24 ± 0.27, p<0.01) and instead increased IL-17 expression (7.18 ± 1.03, p<0.01; Figure 6, right graphs). This evidence concerns the gene CD4 and head and neck squamous cell carcinoma.