Researchers at Johns Hopkins Medicine have discovered a new diagnostic marker that distinguishes a fast-growing type of the pediatric brain cancer medulloblastoma from a less aggressive type. The researchers hope that this biomarker may lead to the development of more effective therapies, according to a press release from the university.
The new study, led by Ranjan J. Perera, PhD, director of the Center for RNA Biology at Johns Hopkins All Children's Hospital, found that this biomarker differentiates aggressive group 3 medulloblastoma from the more treatment-responsive group 4 medulloblastoma. The two types look identical under the microscope and are currently classified as group 3/4 and treated the same, explained Perera, the study’s senior author, who is also a senior scientist at the Johns Hopkins All Children’s Cancer & Blood Disorders Institute and the Johns Hopkins All Children’s Institute for Fundamental Biomedical Research, an associate professor of oncology at the Johns Hopkins University School of Medicine and a Johns Hopkins Kimmel Cancer Center member.
“There is currently no radiographic or microscopic way to distinguish group 3 from group 4,” says George Jallo, MD, pediatric neurosurgeon at Johns Hopkins All Children’s Hospital, medical director of its Institute for Brain Protection Sciences, professor of neurosurgery, pediatrics and oncology at the Johns Hopkins University School of Medicine, and a collaborator on the study. “Children with group 3 medulloblastoma do not respond well to treatment and almost always relapse and die. We currently have no treatment options for this treatment-resistant group other than experimental therapies.”
In an effort to identify features that differentiate group 3 from group 4 and shed light on the cause of its aggressive nature, Perera’s group and collaborators reviewed a public database of 175 medulloblastoma patients’ RNA sequencing data. They found that non-coding RNA – an RNA molecule that is not expressed as a protein but can nonetheless regulate gene expression through other biochemical processes – varied among the four subgroups of medulloblastoma.
In an effort to identify features that differentiate group 3 from group 4 and shed light on the cause of its aggressive nature, Perera’s group and collaborators reviewed a public database of 175 medulloblastoma patients’ RNA sequencing data. They found that non-coding RNA – an RNA molecule that is not expressed as a protein but can nonetheless regulate gene expression through other biochemical processes – varied among the four subgroups of medulloblastoma.
The medulloblastoma is associated with about 35 percent of cases and also has a fair to good prognosis. About 25 percent of patients have group 3, which has a poor prognosis.