Investigation of the effect of cerium dioxide nanoparticles on the radiosensitivity of various cell types

Radiation is one of the factors that constantly affects living organisms. The effect of natural radiation background is supplemented by radiation from artificial radioactive sources, the most common of them are medical devices used as diagnostic and therapeutic equipment. The use of radiation therapy is based on different radiosensitivity of normal and pathologically altered organs, tissues and cells of humans and animals. The search and application of substances that change the sensitivity of living organisms to ionizing radiation to reduce the damaging effect on healthy tissues, while maintaining a positive therapeutic effect, is an urgent issue of modern medical radiobiology. Currently, nanoparticles are widely used as such substances. This paper investigates the effect of mesoporous CeO2 nanopowder on the radiosensitivity of rat alveolar and peritoneal macrophages, dermal fibroblasts, and human cervical carcinoma cells. CeO2 nanoparticles were found to have selective radiomodifying properties in relation to various types of cells. CeO2 nanoparticles had a radioprotective effect on human fibroblasts, increasing their viability after irradiation and speeding up the differentiation of fibroblasts. The nanoparticles acted as radiosensitizers on tumor cells and macrophages, enhancing the damaging effect of ionizing radiation, but the mechanism for increasing sensitivity may be different in each case. The unique enzyme-like properties of cerium dioxide nanoparticles require further investigation of the mechanisms of their action on living systems. This can give an impetus to the development of new effective methods of radiotherapy for various diseases.