BOSTON, Jan. 12, 2014 -- Scientists have identified a mutated gene that causes a type of tenacious, benign brain tumor that can have devastating lifelong effects. Currently, the tumor can only be treated with challenging repeated surgeries and radiation.
The discovery, reported in Nature Genetics, is encouraging, because it may be possible to attack the tumors with targeted drugs already in use for other kinds of tumors, said the investigators from Dana-Farber/Boston Children's Cancer and Blood Disorders Center, Massachusetts General Hospital, and the Broad Institute of MIT and Harvard.
The mutated gene, known as BRAF, was found in almost all samples of tumors called papillary craniopharyngiomas. This is one of two types of craniopharyngiomasthe other being adamantinomatousthat develop in the base of the brain near the pituitary gland, hypothalamus, and optic nerves. The papillary craniopharyngiomas occur mainly in adults; adamantinomatous tumors generally affect children.
The researchers identified a different mutant gene that drives the tumors in children. Drugs that target these adamantinomatous tumors are not yet clinically available, but may be in the future, said the researchers.
"From a clinical perspective, identifying the BRAF mutation in the papillary tumors is really wonderful, because we have drugs that get into the brain and inhibit this pathway," said Sandro Santagata, MD, PhD, a co-senior author of the paper. "Previously, there were no medical treatmentsonly surgery and radiationand now we may be able to go from this discovery right to a well-established drug therapy." BRAF inhibitors are currently used in treating malignant melanoma when that mutation is present.
Priscilla Brastianos, MD, co-first author of the study, and Santagata said plans are underway to design a multicenter clinical trial to investigate the efficacy of a BRAF inhibitor in patients with papillary craniopharyngiomas.
|Contact: Irene Sege|
Dana-Farber Cancer Institute