STAT3 and chronic rhinosinusitis: EGFR and the related phosphorylation status of the signaling pathway induced by ex20ins and HR-HPV infection were investigated by western blotting focusing on EGFR, p-EGFR (Y845, Y1068, Y1086, and Y1197), p-Akt (S473), p-4E-BP1 (T37/46), p-STAT3 (Y705), and p16INK4a in IP, IP-SCC, chronic sinusitis, and SNSCC (Figure 3).