Our first model of HNSCC, LY2 HNSCC cells injected into STAT1-deficient BALB/c mice, is characterized by high levels of PD-1 expression and dampened IFN-γ production in lymph node CD4+ and CD8+ T cells [20] (Figure 4A,B). The gene discussed is IFNG; the disease is head and neck squamous cell carcinoma.