EGFR expression positively correlated with high expression levels of HIF-1α (P = 0.0001, r = 0.4192) and CD31 (P < 0.0001, r = 0.4296) (Fig. 6B; statistic including normal mucosa and HNSCC, n = 71). Here, HIF1A is linked to head and neck squamous cell carcinoma.