Large-scale genomic sequencing has revealed two DNA mutations that appear to drive about 15 percent of brain tumors known as meningiomas, a finding that could lead to the first effective drug treatments for the tumors, report scientists from Dana-Farber Cancer Institute and the Broad Institute.
Surgery and radiation currently are the only treatments for meningiomas – slow-growing, often benign tumors that develop in the membranes surrounding the brain. Meningiomas can grow dangerously large, however, causing seizures and limb weakness, and occasionally are fatal. In some instances, the tumors grow aggressively or their locations make surgery and radiation a challenge to carry out, and chemotherapy has proven ineffective as an alternative.
The researchers report in the journal Nature Genetics that they have identified two mutations, SMO and AKT1, in the genomes of 15 percent of a group of meningiomas removed during surgery. The findings are being published on the journal's web site in advance of appearing in a print edition.
"The wonderful thing about those mutations is that there are already drugs in the clinic to target cancers with those mutations," said Rameen Beroukhim, MD, PhD, a medical oncologist and cancer biologist at Dana-Farber and the Broad Institute.
"Clinically, there is no medical treatment for meningioma that is known to be effective," said Beroukhim, senior author of the paper along with William C. Hahn, MD, PhD, director of the Center for Cancer Genome Discovery at Dana-Farber, and Ian F. Dunn, MD, a neurosurgeon at Dana-Farber/Brigham and Women's Cancer Center (DF/BWCC).
Beroukhim said that surgery can effectively treat many meningiomas, but the locations of some tumors make surgery a difficult or impossible option. For other patients, there are not curative treatments, so the discovery of the mutations in some meningiomas "is potentially the first path to an effective medical treatment," Beroukhim noted.
Meningiomas are diagnosed in about 18,000 patients annually in the United States. They account for about one-third of primary brain tumors (those that originate in the brain) and are twice as common in women. They are generally slow-growing, and many patients don't require treatment unless the tumor expands and presses on vital structures. But a significant number recur following treatment, and many become malignant.
Beroukhim said that little has been uncovered about the genetic makeup of meningiomas. In the current study, the scientists sequenced either the entire genome or just the protein-coding regions (exomes) in samples of 17 meningiomas. Genes that were found to be altered in those tumors were then sequenced in two additional groups of tumors.
Compared to most types of tumors, the researchers found, the meningiomas had fewer numbers of genetic changes or damage. In some of the tumors they found mutations in two genes that have roles in known cancer-causing signaling pathways. One, SMO, found in three tumors, is a member of the Hedgehog pathway. The second, AKT1, was discovered in five tumors and is a part of the PI3K-AKT-mTOR pathways that is implicated in breast, colorectal and lung cancers. A sixth tumor had a previously unknown mutation in the mTOR pathway.
Together, these mutant gene pathways appeared to be key drivers of 15 percent of the meningiomas studied. Experimental drugs that inhibit those abnormal pathways are in clinical trials and have shown promising activity, the researchers said, suggesting "that patients with these meningiomas may benefit from such targeted therapies already in development or use."
Co-first authors of the report are Priscilla Brastianos, MD, of Dana-Farber and Peleg Horowitz, MD, PhD, of Brigham and Women's Hospital. Other authors are at the Broad, Harvard Medical School, Brigham and Women's, and Massachusetts General Hospital.
The research was supported by the Brain Science Foundation, the Pediatric Low-Grade Astrocytoma Foundation, and other foundations, the National Institutes of Health (K08 CA122833, K08 NS064168 and K12 CA090354-11), and the U.S. Department of Defense (W81XWH-12-1-0136.)
Dana-Farber Cancer Institute is a principal teaching affiliate of the Harvard Medical School and is among the leading cancer research and care centers in the United States. It is a founding member of the Dana-Farber/Harvard Cancer Center (DF/HCC), designated a comprehensive cancer center by the National Cancer Institute. It provides adult cancer care with Brigham and Women's Hospital as Dana-Farber/Brigham and Women's Cancer Center and it provides pediatric care with Boston Children's Hospital as Dana-Farber/Children's Hospital Cancer Center. Dana-Farber is the top ranked cancer center in New England, according to U.S. News & World Report, and one of the largest recipients among independent hospitals of National Cancer Institute and National Institutes of Health grant funding. Follow Dana-Farber on Twitter: @danafarber or Facebook: facebook.com/danafarbercancerinstitute.
Bill Schaller | EurekAlert!
Building a brain, cell by cell: Researchers make a mini neuron network (of two)
23.05.2018 | Institute of Industrial Science, The University of Tokyo
Research reveals how order first appears in liquid crystals
23.05.2018 | Brown University
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...
A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.
The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...
02.05.2018 | Event News
13.04.2018 | Event News
12.04.2018 | Event News
23.05.2018 | Life Sciences
23.05.2018 | Life Sciences
23.05.2018 | Physics and Astronomy