ABSTRACT
Objective Taking CNE-2Z multicellular spheroids (MCSs) as the simulation of solid tumors, to investigate the role of SAPK/JNK signaling pathway in multicellular resistance to radiotherapy for human nasopharyngeal carcinoma (NPC). Methods Human NPC cell line CNE-2Z were cultured into multicellular spheroids by using liquid overlay technique, then divided into control MCSs, irradiated MCSs (average dose in one minute: 2 Gy), sp-600125(a specific inhibitor for SAPK/JNK signaling pathway)+irradiated MCSs, sp-600125+MCSs. Western blotting was employed to analyze the activity of SAPK/JNK signaling pathway in MCSs, and the expression of Caspase-3 protein before and after sp-600125 treatment; X-ray induced cell apoptotisis in MCSs before and after sp-600125 treatment was detected by TUNEL. Results The level of SAPK/JNK phosphorylation in MCSs was a dynamic course after radiation, and the phosphorylation peaked at 2 h after irradiation; The apoptotic rate of MCSs (P