Schedule-dependent interaction between anticancer treatments

Abstract

Timing the attack on cancer cells Cell regulatory systems have dynamic properties that will need to be taken into account when planning therapeutic strategies. Chen et al. found that the timing of a radiation treatment of human breast cancer–derived cells in culture determined whether cell survival was enhanced or reduced. Depletion of the oncogene product MDMX caused an initial burst of expression of the tumor suppressor protein p53 within the first 24 hours, and then oscillations of lower amplitude. When the radiation treatment coincided with the first phase, 95% of the cells died, but if radiation was applied in the second phase, fewer than 20% of the cells died. Science , this issue p. 1204