EGFR and head and neck squamous cell carcinoma: At the protein level, upregulation of EGFR and MET in selected HNSCC and LUSC cell lines after IFNγ induction showed a moderate correlation (Supplementary Fig. S5B), while expression of pEGFR and pMET manifested a strong positive correlation (r = 0.9824, P < 0.0001; Fig. 5E).