Up to three quarters of patients receiving cancer chemotherapy suffer from "chemo brain"—a long-term side effect that makes it harder to remember things. Maria Lehtinen, Ph.D. and Naama Kanarek, Ph.D. conducted studies showing the importance of the CSF in promoting brain health and growth, together with the choroid plexus, the little-known brain tissue that produces CSF. Separately, Kanarek has been studying the metabolic effects of the chemotherapy drug methotrexate. In mice, they found methotrexate caused oxidative damage to both the CSF and the choroid plexus. Lehtinen, Kanarek, and colleagues further showed that methotrexate prevented the choroid plexus from secreting superoxide...