A team of researchers, led by Dr. Martine Roussel of the St. Jude Children's Research Hospital has developed a mouse model of medulloblastoma, the most common malignant brain tumor found in children.
Basically, medulloblastomas are malignant tumors that are formed by cells which are not yet mature or in other words by poorly developed brain cells. These tumors are usually formed in the second part of the brain called the cerebellum. It may be recalled here that the cerebellum is the seat of judgment in human beings. The cause of medulloblastomas, which are aggressive tumors, is unknown as of now. Researchers are continuing to look at various possibilities including a defective gene.
In the current study, the researchers have developed a mouse model of the tumor itself, which they hope will enable them to understand the genetic nuances of human brain tumor development. In the research paper, the authors allude to the role of cyclin-dependent kinase inhibitor, INK4C in mediating the development of medulloblastoma.
Dr. Roussel and colleagues have shown through the above-mentioned model that Ink4c inactivation collaborates with a mutation in a gene called Patched (Ptc1, a Shh receptor) to trigger the development of this tumor. "Preliminary data suggest that INK4c protein expression is diminished in a significant cohort of human medulloblastomas," says Dr. Roussel, "so the Pediatric Brain Tumor Program at our Institution is now planning to include a comprehensive survey of INK4c status in order to determine its prognostic significance."
The study will appear in the November 15th issue of Genes & Development
Contact: Heather Cosel
Cold Spring Harbor Laboratory