[4,5,15] The methylation of the gene pair of galanin and GALR1 in the primary tumor was associated with the most significant odds ratio of recurrence, [15] while another study concluded that GALR1 induces cell cycle arrest, and GALR2 induces both cell cycle arrest and apoptosis in HNSCC following galanin treatment. Here, GAL is linked to head and neck squamous cell carcinoma.