CDH1 and head and neck squamous cell carcinoma: Among commonly reported differentially methylated genes in HPV-driven HNSCC are genes involved in cell-cycle regulation (CDKN2A, RASSF1, and CCNA1) [182,183], cellular adhesion (CDH1, CDH8, CDH18, CDH15, CDH13, CDH19 and CDH23, ITGA4) [184,185,186], and tumour progression (TIMP3) [187].