Noninvasive brain biopsy
Taking material for a brain biopsy is a rather complicated and risky procedure. A group of researchers from Washington University in St. Louis (WUSTL) have developed a way to detect reliable biomarkers of a brain tumor using a simple blood test.
Researchers led by bioengineer Hong Chen and neurosurgeon Eric C. Leuthardt have created an innovative method that helps biomarkers penetrate the blood-brain barrier and enter peripheral blood. Focused ultrasonic radiation and microbubbles are used for this purpose.
Scientists have long learned how to overcome the blood-brain barrier in order to deliver drugs from peripheral blood to brain tissue. But overcoming the barrier in the opposite direction for the release of mRNA from brain tissues into peripheral blood is being investigated for the first time.
The authors tested their development on mouse models of two different types of glioblastoma – the most common and dangerous brain tumor. Malignant cells were labeled with fluorescent eGFP protein and grafted into the brains of experimental animals. The tumor was exposed to focused ultrasound radiation, and then micro-bubbles were injected into the blood. They, having reached the blood-brain barrier, began to burst, thus damaging the endothelial layer of blood vessels and increasing their permeability hundreds of times. Biomarkers (eGFP fluorescent protein mRNA) released from the tumor after ultrasound exposure left the brain tissue through the blood-brain barrier and entered the bloodstream. After that, a simple analysis of a blood sample using a polymerase chain reaction revealed biomarkers.
A drawing from become and in Scientific Reports.
This technique allows not only to establish the correct diagnosis, but also to monitor changes in the dynamics of the tumor after the use of various methods of treatment. This cannot be done with a standard surgical biopsy. Focused ultrasound can affect different tumor foci, causing the release of biomarkers from them and allowing conclusions to be drawn about the effectiveness of therapy for each focus separately.
The Group continues to work on improving the method of liquid biopsy. They plan to integrate genome sequencing into the diagnostic system. In addition, it is necessary to evaluate the sensitivity and specificity of this diagnostic method.
Article L. Zhu et al. Focused Ultrasound-enabled Brain Tumor Liquid Biopsy is published in the journal Scientific Reports.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of WUSTL: Noninvasive brain tumor biopsy on the horizon.