AUTHOR=Hou Guowen , Li Jinjie , Liu Wenyun , Wei Jinlong , Xin Ying , Jiang Xin 

TITLE=Mesenchymal stem cells in radiation-induced lung injury: From mechanisms to therapeutic potential

JOURNAL=Frontiers in Cell and Developmental Biology

VOLUME=Volume 10 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/cell-and-developmental-biology/articles/10.3389/fcell.2022.1100305

DOI=10.3389/fcell.2022.1100305

ISSN=2296-634X

ABSTRACT=Radiotherapy (RT) is an effective treatment for multiple thoracic malignant tumors, including lung cancers, thymic cancers, and tracheal caners. Radiation-induced lung injury (RILI) is a serious complication of RT. Radiation causes damage to the pulmonary cells and tissues. Multiple factors contribute to the progression of RILI, including genetic alterations, oxidative stress, and inflammatory responses. Especially, radiation sources contribute to oxidative stress occurrence by direct excitation and ionization of the individual atoms or molecular elements of macromolecules, which leads to the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). Subsequently, ROS and RNS overproduction can induce oxidative DNA damage. Furthermore, immune cells and multiple signaling molecules play a major role in the entire process. Mesenchymal stem cells (MSCs) are pluripotent stem cells with multiple differentiation potentials, which are used to treat RILI. MSCs can protect normal pulmonary cells from injury by targeting multiple signaling molecules to regulate immune cells and to control balance between antioxidants and prooxidants, thereby inhibiting inflammation and fibrosis. Gene-modified MSCs can improve the natural function of MSCs, including cellular survival, tissue regeneration, and homing. These reprogrammed MSCs can produce the desired products, including cytokines, receptors, and enzymes, which can contribute to further advances in the therapeutic application of MSCs. Here, we review the molecular mechanisms of RILI and discuss the potential of MSCs for the prevention and treatment of RILI.