STAT3 and head and neck squamous cell carcinoma: Previous experimental studies on TF interactions in gene regulation support our discovery, for example, NF-κB-AP1-CEBPB [22], [27], NF-κB-STAT3 [26], NF-κB-AP1-EGR1 [29], NF-κB-AP1-SP1 [30], NF-κB-AP1-p53 [48], etc. In HNSCC cell lines, co-binding of RelA, AP1 and CEBPB on IL8 promoter contributed to its over-expression [22].