We analyzed the cytokine expression patterns in six different human tumor cell lines to identify the most suitable line for our experiments and found that HSC4, which is derived from human head and neck squamous cell carcinoma, exhibited high expression of IL-6, M-CSF, IL-8, and VEGF, and was the only line that produced IL-1β (Figure S4 in Supplementary Material). Here, IL6 is linked to head and neck squamous cell carcinoma.