To supplement the relevance of these findings, a combination of immunohistochemistry (IHC) and immunofluorescence (IF) showed that EGFR and MET are highly expressed in HNSCC cells at the invasive front, both in primary tumors and their derivative invasive HNSCC PDO models (Supplemental Fig. 2E). This evidence concerns the gene EGFR and head and neck squamous cell carcinoma.