Glioblastoma multiforme (GBM), an extremely aggressive brain cancer, is a very complex disease. It is characterized by a fast-growing tumor in the brain composed of many subpopulations of cells, including glioblastoma stem cells, which play a crucial role in glioblastoma initiation, expansion and therapy-resistance. GBM’s diverse make up – termed heterogeneity – is of clinical importance because it is a key factor that leads to treatment failure, allowing the tumor to become resistant to treatment or for cancer to recur.
One way to identify different glioblastoma subtypes is by looking at the specific microRNA expressed in the patient derived GBM stem cells. In several types of cancer cells, including glioblastoma cells, microRNA expression isn’t regulated properly. In a new study published in Cell Reports, BWH researchers examined a specific microRNA, miR-128, to help identify glioblastoma subtypes and to determine if altering the microRNA’s presence in glioblastoma cells could change the tumor’s subtype.
“RNA is increasingly recognized as a snapshot of a cell at a given moment in time and therefore gives unique insight into the disease biology,” said lead author Arun Kumar Rooj, PhD, of the Department of Neurosurgery at BWH. “Understanding the dynamic spectrum of cells and their non-coding RNA signatures is critical for advancing therapeutic strategies that will be capable of overcoming the complexity of this disease.”
The researchers looked at miR-128 expression in diverse populations of glioblastoma cells. They identified the “proneural” subtype as having high levels of miR-128 compared to the mesenchymal tumors, which had significantly lower levels of this particular microRNA. Interestingly, they also found that if they raised or lowered the levels of miR-128, they could induce one subtype of tumor to transition into a new subtype.
Read more about Using a microRNA to Shift the Makeup of Glioblastoma Subtypes and other new research stories at BWH Clinical and Research News