EGFR and head and neck squamous cell carcinoma: In the current experimental study, we have investigated the effect of different EGFR inhibitors (cetuximab and erlotinib), the specific c-MET TK inhibitor SU11274 and the RAS protein specific inhibitor zoledronic acid on proliferation and apoptosis of human squamous cell carcinoma cells in vitro as well as on the growth and metastasis of HNSCC xenografts in vivo, alone and in combination as well.