The size and organization of the brain are determined by the activity of progenitor cells early in development. Key mechanisms regulating progenitor cell biology involve miRNAs. These small noncoding RNA molecules bind mRNAs with high specificity, controlling their abundance and expression. The role of miRNAs in brain development has been studied extensively, but their involvement at early stages remained unknown until recently. Here, recent findings showing the important role of miRNAs in the earliest phases of brain development are reviewed, and (...) it is discussed how loss of specific miRNAs leads to pathological conditions, particularly adult and pediatric brain tumors. Let‐7 miRNA downregulation and the initiation of embryonal tumors with multilayered rosettes (ETMR), a novel link recently discovered by the laboratory, are focused upon. Finally, it is discussed how miRNAs may be used for the diagnosis and therapeutic treatment of pediatric brain tumors, with the hope of improving the prognosis of these devastating diseases. (shrink)

In this article, we first review the development of clinical ethics in pediatrics in the United States. We report that, over the last 40 years, most children’s hospitals have ethics committees but that those committees are rarely consulted. We speculate that the reasons for the paucity of ethics consults might be because ethical dilemmas are aired in other venues. The role of the ethics consultant, then, might be to shape the institutional climate and create safe spaces for the discussion of (...) difficult and sometimes contentious issues. Finally, we report how pediatric clinical ethics has evolved differently in a number of other countries around the world. (shrink)