Emerging targets for radioprotection and radiosensitization in radiotherapy.

Radiotherapy is the biggest force acting behind cancer treatment, yet the vast majority of patients get only modest benefit. The successive failure of targeted therapies in radiotherapy lies in the non-discriminative killing of both normal and cancer cells. However, there is still a reason for optimism due to recent advancement made in cancer biology which unrevealed many new deregulated pathways in cancer and their response towards drug and radiation. In this review, we comprehensively discussed novel and promising druggable target which can be exploited for tumor radiosensitization in addition to normal tissue radioprotection in radiotherapy, for better tumor controllability and patient quality of life. In the last part, we also discussed the radiation countermeasure agents in brief.