DAPK1 and head and neck squamous cell carcinoma: Death-associated protein kinase (DAPK), a tumor suppressor gene, is also hypermethylated in head and neck cancer (Sanchez-Cespedes et al. 2000; Choudhury and Ghosh 2015), and hypermethylation is positively correlated with LN metastases and with stages III and IV of HNSCC (Sanchez-Cespedes et al. 2000), as well as inversely correlated with lower expression of DAPK in tongue cancer (Bhat et al. 2017).