This trial aims to assess the safety and effectiveness of using blood stem cells that have been genetically modified to treat children with brain tumours. The clinical trial is being conducted by the Kids Cancer Project in Alexandria New South Wales in conjunction with the Australian Department of Innovation, Industry Science and Research. The trial hopes to recruit 15 children with either high grade primary Glioma or lower grade recurrent brain tumours such as Glioma, Ependymoma, Medulloblastoma or teratogenic tumours among others. Stem cells will be harvested from the participant's blood after they have received an injection of granulocyte colony stimulating factor (G-CSF) to release the stem cells from their bone marrow. The stem cells will be genetically modified in the laboratory to make them more resistant to chemotherapy drugs. The trial participants will receive an intravenous (IV) infusion of these expanded, modified stem cells, and then 21 days later be treated with standard chemotherapy for such tumours. Participants will be monitored for complications and the effectiveness will be assessed by conducting MRI scans of the brain. The trial commenced in July 2012.