MAPK1 and nasopharyngeal carcinoma: The results showed that MEK inhibitor U0126, PI3K inhibitor LY294002 or AKT1 DNAzyme significantly abrogated cell radioresistance induced by RKIP knockdown in the radiosensitive NPC cells, and transfection of ERK-2 or AKT1 expression plasmid restored cell radioresistance reduced by RKIP overexpression in the radioresistant NPC cells.