MONDAY, Dec. 7 (HealthDay News) -- Scientists have identified oncogenes that play a role in a particularly aggressive type of childhood brain tumor.
Known as central nervous system primitive neuroectodermal tumors (CNS-PNETs), the discovery of these oncogenes may lead to improved diagnosis and treatment of the deadly condition.
"Lack of insight into the molecular pathogenesis of CNS-PNET is a major obstacle towards development of disease-specific models and treatments for these frequently fatal malignancies," noted senior study author Dr. Annie Huang, of the Hospital for Sick Children in Toronto.
She and colleagues from Asia, Europe and the United States conducted a high resolution genomic screen of CNS-PNET tumors and found that a DNA segment that contains a group of 54 microRNA (miRNA) genes was present in many copies in aggressive tumor cells.
The specific miRNAs from this C19MC group can stimulate growth and prevent development of normal human neural stem cells into more mature types of brain cells, the researchers said. They also found that the C19MC miRNA oncogenes can cause aggressive tumors by altering signaling pathways that regulate normal neural stem cell growth.
"Our findings highlight C19MC as an attractive candidate biomarker and therapeutic target for aggressive pediatric brain tumors and support an emerging theme that miRNAs are important determinants of tumor biology," Huang said. "Together with recent reports which implicate C19MC miRNAs in aggressive primary breast cancer, our findings suggest activation of the C19MC locus may generally define aggressive human tumors."
The study appears in the December issue of Cancer Cell.
The Nemours Foundation has more about childhood brain tumors.
SOURCE: Cell Press, news release, Dec. 7, 2009