Children’s brain tumor linked to neural stem cells

Medulloblastomas are malignant tumors formed from poorly developed cells at a very early stage of their life. They develop in the cerebellum, in a part of the brain called the posterior fossa, but may spread to other parts of the brain. Very rarely, medulloblastomas may spread to other parts of the body. If they do spread to other parts of the brain, or to the spinal cord, this is usually through the cerebrospinal fluid (CSF). CSF is the fluid that surrounds and protects the brain and the spinal cord. Medulloblastomas are more common in children, particularly between the ages of three and eight. They make up about one in five (20%) of all childhood brain tumors. The tumor is more common in boys than girls. They can also occur in adults, but this is extremely rare.

The cause of this tumor is unknown and is often noticed that unlike other forms of brain tumors, Medulloblastomas don’t seem to respond well to treatment. Researchers from Queen Mary, University of London, have found a possible reason for this phenomenon. Their study that has been published in Oncogene, shows that Medulloblastomas arise from brain stem cells and might require a totally new approach to treat them. Human brain possess small amount of stem cells known as neural stem cells that help in repairing damage to brain tissue to a certain degree. Silvia Marino, Professor of Neuropathology at Queen Mary, University of London, who led the study, isolated these neural stem cells from mice brain and discovered that mutations in two specific genes- Rb and p53 which play a vital role in cancer could cause the stem cells to divide abnormally leading to Medulloblastomas. This is the first time researchers have been able to show that tumors can develop from endogenous stem cells thus providing a better understanding of the cause and development of this form of tumor which can aid in more effective treatment approaches.