Synergistic Effect of Combination Topotecan and Chronomodulated Radiation Therapy on Xenografted Human Nasopharyngeal Carcinoma

This study suggested that TPT combined with chronoradiotherapy could enhance the radiosensitivity of xenografted NPC. The TPT+RT group at 15 HALO had the best therapeutic effect. The chronomodulated radiosensitization mechanisms of TPT might be related to circadian rhythm of tumor hypoxia, cell cycle redistribution, DNA damage, and expression of Top I.