Brain and nervous system cancers in children represent the second most common neoplasia after leukemia. Radiotherapy plays a significant role in cancer treatment; however, the use of such therapy is not without devastating side effects. The impact of radiation-induced damage to the brain is multifactorial, but the damage to neural stem cell populations seems to play a key role. The brain contains pools of regenerative neural stem cells that reside in specialized neurogenic niches and can generate new neurons. In this review, we describe the advances in radiotherapy techniques that protect neural stem cell compartments, and subsequently limit and prevent the occurrence and development of side effects. We also summarize the current knowledge about neural stem cells and the molecular mechanisms underlying changes in neural stem cell niches after brain radiotherapy. Strategies used to minimize radiation-related damages, as well as new challenges in the treatment of brain tumors are also discussed.

Department of Radiation Dosimentry Nuclear Physics Institute of the Czech Academy of Sciences v v i Na Truhlářce 39 64 180 00 Prague 8 Czech Republic

Laboratory of Cell Differentiation Institute of Molecular Genetics of the Czech Academy of Sciences v v i Vídeňská 1083 142 20 Prague 4 Czech Republic

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Special Issue: Animal Modeling in Cancer