ExRNA in Biofluids as Biomarkers for Brain Tumors

EV RNAs have tremendous clinical potential as diagnostic, subtype-defining, and prognostic biomarkers in GBM. The identification of new EV RNA targets and validation of existing EV RNA targets will be accelerated by large-scale biorepositories established for clinic sample warehousing and ongoing standardization studies to streamline sample processing. Parallel efforts to understand EV dynamics in other neurologic diseases are also underway, and include Parkinson’s disease, Alzheimer’s disease, neurotrauma, and low-grade gliomas. As such, EV RNA may one day replace invasive approaches to diagnose, subtype, and track disease progression in not only GBM, but also a myriad of neuro-pathologies.

• Patients with high-grade gliomas and glioblastomas (GBMs) have poor survival despite optimal surgical and drug therapy.
• Minimally invasive diagnostic biomarkers would enable early diagnosis and tumor-specific treatments for ‘personalized targeted’ therapy, and would create the basis for response tracking in patients with GBM.
• Extracellular vesicles (EVs) isolated from cerebrospinal fluid and blood contain glioma-specific molecules, including tumor-derived EV RNAs that are detectable in small copy numbers in these biofluids.
• EV RNA mutations or expression changes are also detectable, the analysis of which gives rise to ‘liquid biopsy’ tumor profiling.