PKD2 and head and neck squamous cell carcinoma: According to previous reports, several biomarkers of HNSCC, including SDF-1, CXCR4, HMGA2, CDKN2A, and TRPP2 (De-Colle et al., 2017; Palumbo et al., 2018; Chen et al., 2018; Wu et al., 2016), may potentially be used as therapeutic targets to overcome HNSCC.