E2F4 mainly localized in the nucleus, and showed markedly higher expression in HNSCC tissues than in normal pericancerous tissues; E2F4 had a high expression rate of 72.04% (67/93) in T3–4 HNSCC, significantly higher than that in of 46.38% in T1–2 HNSCC (32/69; P < 0.05, Fig. 6, Table 2). This evidence concerns the gene E2F4 and head and neck squamous cell carcinoma.