However, higher levels of TEX-bound CTLA-4 and other immunosuppressive markers (PD-L1, COX2, CTLA-4, CD15s, or CD44v3) in the plasma of HNSCC patients have been shown to be associated with increased apoptosis of activated CD8+ T-cells [142,143]. Here, CD8A is linked to head and neck squamous cell carcinoma.