DACH1 and oropharynx squamous cell carcinoma: The aim of the present study was to assess the frequency of gene promoter methylation of Wnt pathway antagonists (DACH1, DKK1, LKB1, PPP2R2B, RUNX3, SFRP2, and WIF-1) in oropharyngeal squamous cell carcinoma cell lines and establish the diagnostic potential of the most promising genes in respect to correlation with important clinicopathologic data such as tumor recurrence or disease-free survival in a group of oropharyngeal cancer patients.