EGFR and head and neck squamous cell carcinoma: Subsequently, HNSCC cell lines were treated with EGFR inhibitors (gefitinib and erlotinib), and SEMA7A-5NQ cells were found to be more sensitive to EGFR-targeted therapy, as evidenced by the elevated cleaved Caspase-3 activity and decreased cell proliferation rate (Supplementary Fig. 12b, c).