In CAL27 cells induced by low-dose arecoline, we observed promoter methylation of SALL3, IRF8, TSHZ3 and CRMP1. SALL3 methylation could clearly distinguish HNSCC from adjacent normal mucosal tissue, thus being an independent predictor of poor survival in HNSCC [55]. The gene discussed is TSHZ3; the disease is head and neck squamous cell carcinoma.