LY6D and head and neck cancer: Promising markers for head and neck cancers include parathyroid hormone-like hormone (PTHLH, also known as PTHrP), serpin peptidase inhibitor, clade B (ovalbumin), member 3 (SERPINB, also known as SCCA), and lymphocyte antigen 6 complex, locus D (LY6D, also known as E48) [8,29,30].