Fig. 1
From: microRNAs identified in prostate cancer: Correlative studies on response to ionizing radiation
Radiation effects on tumor cells and the tumor microenvironment. Damage induced by ionizing radiation lead to numerous cell effects in the cell and within the tumor microenvironment (TME). Irradiation causes DNA damage which triggers DNA damage response to repair the damaged DNA, induce cell cycle arrest or cell death. Reactive oxygen species (ROS), produced following irradiation, are also implicated in radiation responses. In the TME, tumor endothelial cells sensitive to irradiation undergo apoptosis resulting in vascular destruction and hypoxia. Hypoxia stimulates DNA repair through the androgen receptor (AR) leading to less faithful DNA repair and accumulation of mutations. Radiation also promotes bystander and abscopal effects. One of these changes is an increase of tumor cell antigen availability which activates dendritic cells (DC) and T cells to eradicate tumor cells. DHT, dihydrotestosterone; HIF-1α, hypoxia-inducible factor-1α