For example, aberrant methylation and silencing of neuropeptides and GPCRs, including galanin and galanin receptors (GALR1 and GALR2) [59], tachykinin-1 and tachykinin receptor (TACR1) [60], and somatostatin and somatostatin receptor (SST and SSTR1) [61] are common in HNSCC. This evidence concerns the gene SST and head and neck squamous cell carcinoma.