International collaborators, including researchers from Children's National Health System, have unraveled profiles in the genetic makeup of tumor cells in children that could more readily identify their growth and response to treatment, offering the possibility of better, more precise therapy.
While there has been a longtime belief that results from single biopsies can represent entire brain tumors, the new research has shown that separate molecular profiles exist that would allow clinicians to use specific therapy to target deep-rooted cancerous growths, says Roger J. Packer, MD, Senior Vice President, Center for Neuroscience and Behavioral Health at Children's National, and one of the leaders of the study. The study was published in Molecular and Cellular Pediatrics stemming from a workshop earlier this year in Göttingen, Germany.
In the study, the researchers assessed tumor heterogeneity, the observation that different tumor cells can show distinct profiles in their genetic make-up, affecting their growth and response to treatment. Each tumor cell may be highly diverse, and may not represent the entire tumor.
Researchers sorted out distinctive molecular profiles of genes and molecular pathways controlling tumor development. Molecular profiling identifies biomarkers of gene mutations inside tumor cells that may cause them to be cancerous. By investigating the puzzle of the molecular profiles, clinicians may find new ways to improve efficiency and quality of care for each patient. The profiles of genes and molecular pathways control tumor development; genes and pathways that can be specifically targeted for treatment.
"There was a feeling that one size fits all, now we know that one size doesn't fit all," says Dr. Packer, referring to previous understanding of scientists that single biopsies of tumors can reflect the cell structure of an entire mass, which is no longer the case. "This is one of the ways researchers are changing the way we understand pediatric brain tumors, the leading cause of pediatric cancer-related deaths, and making way for better therapy," Dr. Packer says.
"We can now pinpoint a molecular subgroup with certainty, and the tumor can respond to a very specific type of treatment," Dr. Packer says. "That's exciting to us because it gives us a new window to treat the disease."
In essence, the study paves the way for continued clinical development of drugs and exploring specific needs of patients "to improve therapies that now exist," Dr. Packer said.
As head of the Brain Tumor Institute and the Gilbert Family Neurofibromatosis Institute at Children's National, Dr. Packer has conducted leading research into neurological disorders in children and the impact treatment has on neurological and cognitive outcomes. Packer is also a Professor Neurology and Pediatrics at the George Washington University in Washington, DC.
Dr. Packer said there has been progress in fighting neurological ailments in children, with survival rates for childhood medulloblastoma increasing up to 90 percent for some subsets of children. In addition, therapies have become somewhat less toxic.
Still, he says, more work needs to be done.
"The field of pediatric brain research has grown exponentially with international collaborations between researchers and clinicians," Dr. Packer says. "We have international groups that are working to improve quality of life for these children and working to find the therapy needed for long-term disease control."