EGFR and head and neck squamous cell carcinoma: Some researchers have used small interfering RNAs to suppress E6 expression and erlotinib to downregulate EGFR activity and thereby eliminate the nuclear localization of β-catenin and the phosphorylation of EGFR while reducing the invasion characteristics of HPV + HNSCC cell lines in vitro (Nwanze et al., 2015).