We also observed that endothelial cell-derived interleukin-6 (IL-6) and epidermal growth factor (EGF) induce the activity of the signal transducer and activator of transcription 3 (STAT3) and extracellular signal-regulated kinase (ERK) in head and neck cancer cells, resulting in enhanced tumor cell proliferation and protection against anoikis [22]. Here, STAT3 is linked to head and neck cancer.