VIP and head and neck squamous cell carcinoma: To determine whether the murine model of HNSCC we use is innervated similar to its human counterpart, mice were injected with mEERL cells in the hind limb (1 × 105 cells/mouse), tumors harvested at endpoint, fixed, embedded and IHC stained for β-III tubulin, TH, VIP, and TRPV1.