AIMP2 and nasopharyngeal carcinoma: To further evaluate the role of AIMP2-DX2 in NPC and the downstream mechanisms, the mRNA and protein expression levels were measured by RT-PCR and western blotting in cultured immortalized nasopharyngeal epithelial cell line (NP69) and NPC cell lines (5-8F, CNE-1, and CNE-2Z).