Furthermore, many other major hotspot mutations, including HRAS p.G12V, MAPK1 p.E322K/p.D321N, MAP2K1 p.K57N, and MAP2K2 p.F57L mutations all inhibited p-ErbB3(Y1289) expressions in HNSCC cell models (Figs 2B and S4A). Here, MAP2K1 is linked to head and neck squamous cell carcinoma.