A type of RNA, previously considered to be “junk,” may help doctors distinguish and treat a subgroup of young patients with medulloblastoma, according to a new study by researchers at the Johns Hopkins Kimmel Cancer Center.
Medulloblastoma is the most common malignant brain tumor in children, accounting for about 20% of all pediatric brain cancers. Four groups of medulloblastomas have been identified, and one is named sonic hedgehog (SHH) because of the spiky, hedgehog-like appearance of fruit flies missing the gene.
“We have identified a new molecule that is specific for the sonic hedgehog group of medulloblastomas. We believe that this molecule is important for early detection, and we would like to use this molecule marker as a therapeutic target,” says senior study author Ranjan Perera, director of the Center for RNA Biology and senior scientist at the Cancer & Blood Disorders Institute at Johns Hopkins All Children’s Hospital.
The ability to better distinguish between subtypes of medulloblastomas has important implications for developing treatments and improving survival.
SHH medulloblastoma is the most common form in patients younger than 3 years old and accounts for around 30% of all medulloblastomas.
“This research identifies a new and novel target to treat medulloblastoma, a much-needed advance for this aggressive pediatric cancer,” says Chetan Bettegowda, Jennison and Novak Families Professor of Neurosurgery.
RNA plays a part in how genes work and what they do. Noncoding RNA, which doesn’t produce proteins, was called “junk RNA” for many years. Scientists are now unraveling what role noncoding RNA plays in the body.
Circular RNA (circRNA) is a type of noncoding RNA that is thought to play a role in the development of different types of cancers, making them good targets for cancer drug development. In addition, circRNAs are abundant in the brains of mammals, which makes them potential biomarkers of medulloblastoma and its subtypes.
“Although tremendous improvements have occurred in therapies and supportive care, there is more work to be done on the subclassifications and how these subgroups can be managed uniquely by improved molecular diagnostics and targeted therapies,” says Stacie Stapleton, director of pediatric neuro-oncology and member of the Cancer & Blood Disorders Institute at Johns Hopkins All Children’s Hospital. “The discovery of this circular RNA in SHH medulloblastoma is promising to help with diagnostics and therapeutics to help the children we see in clinic.”
The findings are reported in the journal Acta Neuropathologica Communications.