MAPK3 and low grade glioma: Unfortunately, a selectively inhibitor of JNK approved for clinical trials has not been found; so we chose trametinib, an inhibitor of MEK1/2, an upstream effector of p38, JNK and ERK1/2, that is being investigated in the treatment of pediatric low-grade gliomas and plexiform neurofibroma in an ongoing multicenter phase II trial [25] (Fig. 4B and Supplementary Fig. S4B).