IKBKB and head and neck squamous cell carcinoma: Since the combination of EGFR and IKK inhibitors effectively blocked three crucial downstream pathways of EGFR, PI3K/Akt/mTOR, ERK and IKKβ/NF-κB, we concluded that the inhibitors synergised to induce apoptosis and suppress cell proliferation in HNSCC (Fig. 7, right panel).