TY - JOUR AR - COCB-2019-1-102 TI - The Pathway from Radiation to Fibrosis: LET Dependence AU - Huichen, Wang AU - Kareena M., Menezes AU - Premkumar B., Saganti JO - Clinical Oncology and Cancer Biology PY - 2019 DA - Mon 16, Dec 2019 SN - 2733-2276 DO - http://dx.doi.org/10.31487/j.COCB.2019.01.02 UR - https://www.sciencerepository.org/the-pathway-from-radiation-to-fibrosis_COCB-2019-1-102 KW - Radiation-induced fibrosis (RIF), myofibroblasts, reactive oxygen species (ROS), transforming growth factor-β (TGF-β), linear energy transfer (LET) AB - It is well-known that Radiation-induced fibrosis (RIF) is a late event occurring months to years after the initial radiation exposure. Fibrotic lesions have been shown to manifest in many tissues including the skin, heart, lung, liver and kidney. Fibrosis occurs due to abnormal accumulation of extracellular matrix (ECM) proteins that result in loss of normal tissue and organ function. The cell type involved in RIF is myofibroblasts, which do not undergo apoptosis after healing but instead continue to accumulate, producing excessive amounts of ECM proteins, thereby damaging the tissues and organs. Reactive oxygen species, generated in response to radiation, is one signal that helps maintain the myofibroblast phenotype. In this review, we discuss molecular mechanisms leading to this late radiation event, known biomarkers for prediction, preclinical animal models of radiation-induced toxicity and current clinical trials designed for mitigation and treatment of radiation-induced fibrosis. We also discuss other physical properties such as linear energy transfer (LET) than the ones used in the clinics today which may have the potential to change our understanding on this inevitable pathway from radiation treatment to organ fibrosis.