In contrast, early effector cell-dependent infiltration within 20–30 min and restored anti-tumor reaction was observed by PP-treated NK cells against cetuximab-coated HNSCC clusters after 1 h (Figure 5A, upper row) accompanied by raised IFN-γ and TNFα medium levels (24 h PP + 1 μg/ml Cetmab + 4 h HNSCC cells, Figure 5D). Here, TNF is linked to head and neck squamous cell carcinoma.