CD8A and head and neck squamous cell carcinoma: HNSCC patients in the subtype of high DKK1 expression presented lower infiltration levels of memory B cells (p < 0.05), CD8+ T cells (p < 0.001), follicular helper T cells (p < 0.001), Tregs (p < 0.001), and activated mast cells (p < 0.05) while having higher infiltration levels of resting NK cells (p < 0.01), M0 macrophages (p < 0.05), and resting mast cells (p < 0.01) (Figure 6D).