Figure 3:

Schematics of some relevant pathways leading to tumor cell kill and normal tissue toxicities. Starting with direct and indirect DNA damage to the tumor and parenchyma, there are repair pathways that, upon failure, lead to cell kill of tumor cells (left) or damage to functional subunits (right). The text in green indicates pathways related to in vitro cell kill studies. In addition to direct damage to cells, there is radiation-induced damage to vasculature leading to vascular disruption which impacts tumor and normal tissue response. Similarly, adaptive and innate immune response are impacted by radiation. Clinically relevant endpoints are indicated in red. Note that the two empty blue boxes are placeholders for mirrored images of the upper two blue boxes.