CD8A and head and neck squamous cell carcinoma: On the contrary, HPV+ve HNSCC tumors are infiltrated with increased Tregs, Tregs/CD8+, and CD56low NK cells, CD56+ CD3+ NKT cells, CD3+ T cell, and activated T cells with increased CTLA4 and PD-1 expression and PD-1/TIM3 co-expressing CD8+ T cells, suggesting compromised immune system [57].