Аннотация:In this work, we developed a computational method in systems radiobiology to investigate effectiveness of RT in combination with targeted therapy which directs at the inhibition of NRF2 antioxidant system of cancer cells (AOS). NRF2 transcriptional factor is a key element of the defensive cellular system which is activated under oxidative stress in cells induced in part by ionizing radiation. Its activation triggered by the increasing reactive oxygen species (ROS) in the cells leads to the expression of a large number of antioxidant enzymes which neutralize ROS. We assumed that suppression of the NRF2 AOS in cancer cells enhances the sensitivity of the cells to RT due to the increasing damage of cancer cell DNA by ROS generated by water radiolysis.