New technique developed at Washington University in St. Louis uses blood test
From the WashU Newsroom…
Taking a biopsy of a brain tumor is a complicated and invasive surgical process, but a team of researchers at Washington University in St. Louis is developing a way that allows them to detect tumor biomarkers through a simple blood test.
Hong Chen, a biomedical engineer, and Eric C. Leuthardt, MD, a neurosurgeon, led a team of engineers, physicians and researchers who have developed a groundbreaking, proof-of-concept technique that allows biomarkers from a brain tumor to pass through the tough blood-brain barrier into a patient’s blood using noninvasive focused ultrasound and some tiny bubbles, potentially eliminating the need for a surgical biopsy.
Chen, assistant professor of biomedical engineering in the School of Engineering & Applied Science and of radiation oncology in the School of Medicine, said while researchers have already learned how to get a drug through the blood-brain barrier into the brain via the bloodstream, no one — until now — has found a way to release tumor-specific biomarkers — in this case, messenger RNA (mRNA)— from the brain into the blood.
“I see a clear path for the clinical translation of this technique,” said Chen, an expert in ultrasound technology. “Blood-based liquid biopsies have been used in other cancers, but not in the brain. Our proposed technique may make it possible to perform a blood test for brain cancer patients.”
The blood test would reveal the amount of mRNA in the blood, which gives physicians specific information about the tumor that can help with diagnosis and treatment options.
Results of the study, which blends imaging, mechanobiology, genomics, immunology, bioinformatics, oncology, radiology and neurosurgery, are published in Scientific Reports April 26, 2018.
Chen; Leuthardt, professor of neurological surgery in the School of Medicine; and researchers from the Schools of Engineering & Applied Science and of Medicine, tested their theory in a mouse model using two different types of the deadly glioblastoma brain tumor. They targeted the tumor using focused ultrasound, a technique that uses ultrasonic energy to target tissue deep in the body without incisions or radiation. Similar to a magnifying glass that can focus sunlight to a tiny point, focused ultrasound concentrates ultrasound energy to a tiny point deep into the brain.
Once they had the target — in this case, the brain tumor — researchers then injected microbubbles that travel through the blood similar to red blood cells. When the microbubbles reached the target, they popped, causing tiny ruptures of the blood-brain barrier that allows the biomarkers from the brain tumor to pass through the barrier and release into the bloodstream. A blood sample can determine the biomarkers in the tumor.
This technique could lead to personalized medicine.