Multiple studies had shown that radiation activated the PI3K/AKT/mTOR signaling pathway in a variety of tumor cell types, including human glioblastoma, cervical cancer, colorectal cancer and nasopharyngeal carcinoma 45-48.Our results were similar in that expression of PI3K p110β/p-AKT proteins were increased after IR. This evidence concerns the gene MTOR and nasopharyngeal carcinoma.