TAC1 and head and neck squamous cell carcinoma: We prospectively analyzed 11 genes involved in cell cycle control (p16, galanin receptor 1; GALR1), DNA damage repair (O6-alkylguanine DNA alkyltransferase; MGMT), apoptosis (death-associated protein kinase; DAPK, Ras association domain-containing protein 1; RASSF1A), inflammatory reactions (tachykinin, precursor 1; TAC1), antitumor and antisecretory activity (somatostatin; SST), and tumor cell invasion (E-cadherin, H-cadherin, deleted in colorectal carcinoma [DCC], and collagen alpha-2(I) chain [COL1A2]) in a cohort of clinically well-characterized HNSCC samples.