title: Radioprotection of normal tissue cells.
abstract: Improvements of radiotherapy in combination with surgery and systemic therapy have resulted in increased survival rates of tumor patients. However, radiation-induced normal tissue toxicity is still dose limiting. Several strategies have been pursued with the goal to develop substances which may prevent or reduce damage to normal tissue. Drugs applied before radiotherapy are called radioprotectors; those given after radiotherapy to reduce long-term effects are radiomitigators. Despite more than 50 years of research, until now only two substances, amifostine and palifermin, have overcome all obstacles of clinical approval and are applied during radiotherapy of head and neck cancer or total body irradiation, respectively. However, better understanding of the cellular pathways involved in radiation response has allowed the development of several highly promising drugs functioning as scavengers of reactive oxygen species or targeting specific molecules involved in regulation of cell death pathways or cell cycle arrest. The present review describes the major targets for radioprotectors or radiomitigators currently tested in clinical trials.
authors.affiliation: Department of Radiation Oncology Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Theodor-Kutzer-Ufer 1-3, 68167, Mannheim, Germany, patrick.maier@medma.uni-heidelberg.de.
authors.forename: Patrick
authors.initials: P
authors.lastname: Maier
authors.forename: Frederik
authors.initials: F
authors.lastname: Wenz
authors.forename: Carsten
authors.initials: C
authors.lastname: Herskind
mesh_terms: D004999:Amifostine / Q000494:pharmacology; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects*; D002986:Clinical Trials as Topic; D004249:DNA Damage / Q000187:drug effects / Q000528:radiation effects; D019583:Dose Fractionation, Radiation; D051523:Fibroblast Growth Factor 7 / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000494:pharmacology*; D006801:Humans; D018499:Linear Energy Transfer; D010039:Otorhinolaryngologic Neoplasms / Q000473:pathology / Q000532:radiotherapy; D011832:Radiation Injuries / Q000473:pathology / Q000517:prevention & control*; D011837:Radiation-Protective Agents / Q000494:pharmacology*; D017382:Reactive Oxygen Species / Q000528:radiation effects; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000528:radiation effects*; D014916:Whole-Body Irradiation / Q000009:adverse effects
chemical_list: D016166:Free Radical Scavengers; D011837:Radiation-Protective Agents; D017382:Reactive Oxygen Species; D051523:Fibroblast Growth Factor 7; D004999:Amifostine