MAPK3 and nasopharyngeal carcinoma: Finally, SCZ NPC also displayed increased phosphorylation of key MAPK proteins (Fig. 5E), namely c-Raf (S289/296/301), Erk2 (T202/Y204), Erk1 (T202/Y204) and Ribosomal S6 kinase (RSK) 1 (T573).