IFNG and head and neck squamous cell carcinoma: Moreover, the medium supernatants of those incubated samples (PP-cultured NK cells and cetuximab-coated HNSCC tumor spheroids) revealed significantly increased IFN-γ and TNFα secretion levels (24 h PP + 1 μg/ml Cetmab + 24 h HNSCC tumor spheroids, Figure 5D).