We found that the IC50 (half-inhibition concentration) values of most HNSCC cells (HN4, HN6, HN30, CAL27, SCC9 and SCC25) to EZH2 inhibitors (GSK343, GSK126 and EPZ6438) was higher than 10 μM (Fig. 1A). Here, EZH2 is linked to head and neck squamous cell carcinoma.