THE ROLE OF CYTOKINES IN RADIATION-THERAPY FOR CANCER

Recent advances in molecular genetics, cell biology, radiobiology, and immunology have stimulated great interest in applying the newly gaine d information to improve the treatment of cancer, During the last deca de, a number of novel strategies have emerged, Among the most promisin g is the use of genetically engineered cytokines, alone and in concert with conventional modalities such as radiation, Cytokines are polypep tides that play important roles in many biological processes, includin g hematopoiesis, tissue repair, immunity, and tumorigenesis. These mol ecules have the potential to modify the outcome of radiation, one of t he major forms of cancer therapy. This review focuses on four aspects of interaction between cytokines and radiation: a) radiation-induced a ctivation of cytokine genes, b) cytokines as mediators of radiation-in duced damage to normal tissues, c) cytokines as radioprotectants, and d) cytokines as enhancers of radiation antitumor effects, It should be emphasized that our understanding of the complex actions and interact ions that occur among the many cytokines is incomplete and there are i ndications that the effect of radiation on cells and tissues is more c omplex than originally believed, At least some of the currently accept ed concepts are likely be modified as new research data continue to be generated.