DCC and head and neck squamous cell carcinoma: In particular, we detected frequent methylation of p16 (44.4%), RASSF1A (18.0%), E-cadherin (53.6%), H-cadherin (35.3%), MGMT (35.3%), DAPK (53.4%), DCC (42.1%), COL1A2 (44.4%), TAC1 (61.0%), SST (64.0%), and GALR1 (44.4%) in HNSCC (Figure 1B).