Since we previously showed that erlotinib induced IL-1α in HNSCC cells [16] and we developed the ER-HNSCC cells by chronically exposing ES-HNSCC cells to erlotinib; it is likely that this chronic exposure had led to sustained activation of IL-1 signaling via IL-α release. This evidence concerns the gene TNFRSF9 and head and neck squamous cell carcinoma.