Precision medicine makes its way to one of the most complicated organs in the body: the brain. Researchers from the University of Pittsburgh School of Medicine have developed a new sequencing test
that can rapidly profile brain tumors and guide the treatment of brain cancers.
Whether it’s a primary tumor or one that’s metastasized, brain cancer remains one of the scariest diagnoses that a patient can receive. According to the American Brain Tumor Association, every year nearly 70,000 new cases of primary brain cancers will be diagnosed. And every year, 14,000 people will succumb to the disease.
"The diagnosis of brain tumors has been based primarily on cellular features seen under the microscope," said Dr. Marina Nikiforova, senior investigator and director of UPMC's Molecular & Genomic Pathology Laboratory. "However, patients with tumors that look identical may experience different clinical outcomes and responses to treatment because the underlying genetic characteristics of their tumors differ.”
To find the underlying genetic changes in brain tumors, Dr. Nikiforova and her team designed a genetic sequencing panel that simultaneously analyzes 68 of the most commonly mutated genes associated with brain cancers. The test, called GlioSeq™
, is performed using DNA from very small biopsy tissues from the brain cancers.
In a performance evaluation of 54 adults and pediatric brain cancer samples, GlioSeq correctly identified, with 100% accuracy, all the genetic alterations that are known from conventional assays. This included all single nucleotide variants, small deletions and insertions, gene fusions, and copy number variations.
“We designed this panel to quickly identify those traits from very small biopsies of the brain lesion,” said Dr. Nikiforova. Indeed, the test uses next-generation sequencing, a platform that’s heralded for its speed and affordability. And unlike other conventional assays, GlioSeq requires the tiniest amounts of genetic materials for analysis (20 ng of DNA, and 10 ng of RNA).
Most importantly, GlioSeq provides clinicians with personalized genetic information on a patient’s brain tumor. With this genetic profile, doctors can accurately classify the tumor type, which is the first step in developing a targeted treatment plan that’s tailored for the patient. Knowing the mutated genes could also allow doctors to better predict patient survival as they can anticipate patient response to certain therapies.
"Using GlioSeq™ helps us to understand in detail the genetic profile of brain tumors, and takes us one step closer to personalized management of our patients," Dr. Nikiforova said. "We are also working on further improving this test to include additional, recently discovered molecular alterations."
Interested in how next-generation sequencing works? Watch this video for an amusing and unforgettable explanation.
Additional source: MNT