TLR3 and head and neck squamous cell carcinoma: Its abundance was at a maximal level in extracts from NPC cells and xenografts followed by extracts from HNSCC cells (SQ20B and FaDu) ; in contrast, TLR3 was undetectable or at a low level in extracts from other carcinoma cells or from non-tumorigenic nasopharyngeal epithelial cells (Figure1C).