STING1 and cancer: Even before the flavone acetic acid derivative called 5,6-dimethylxanthenone-4-acetic acid (DMXAA) was known to be a STING agonist, it was understood to elicit anti-cancer activity through anti-vascular and anti-immune effects (Daei Farshchi Adli et al., 2018), and demonstrated synergy with ionizing radiation (Pedley et al., 1996; Wilson et al., 1998).