(MEMPHIS, Tenn. September 19, 2011) The largest study ever of a rare childhood brain tumor found more than half the tumors carried extra copies of specific genes linked to cancer growth, according to research led by St. Jude Children's Research Hospital investigators.
The findings identify possible new targets for treatment of a tumor in the brainstem known as diffuse intrinsic pontine glioma (DIPG). Current survival rates for children with this cancer are low. Fewer than 10 percent of DIPG patients are alive two years after diagnosis. DIPGs account for 10 to 15 percent of pediatric tumors of the brain and central nervous system.
This study analyzed 43 tumors. Forty-seven percent carried extra copies of genes that transmit signals for cell growth and survival. In 30 percent of tumors, the amplification involved different genes that help control cell division. Twenty-one percent of tumors included genes involved in both mechanisms. The research appears in the September 19 online edition of the Journal of Clinical Oncology.
"Our findings have potential therapeutic relevance and suggest it may be useful to combine drugs that target the pathways disrupted in these tumors both broadly and selectively," said Suzanne Baker, Ph.D., the paper's senior author and member of the St. Jude Department of Developmental Neurobiology.
The work also provided insight into DIPG's origins and added evidence that DIPG is a distinct tumor subtype within a category of brain and spinal tumors known as gliomas. The findings offer the most detailed picture yet of the molecular missteps, including chromosomal changes and altered gene activity, that characterize this tumor.
Efforts to improve patient survival have been hampered in part by limited DIPG samples. "These tumors are one of the most understudied types of cancer because the tumor infiltrates the brainstem, which controls vital functions. It cannot be surgically removed," Baker
|Contact: Carrie Strehlau|
St. Jude Children's Research Hospital