Source: Washington University of St. Louis
Summary: A team of researchers is developing a way that allows them to detect tumor biomarkers through a simple blood test.
Taking a biopsy of a brain tumor is a complicated and invasive surgical process. Blood-based liquid biopsies have been used in other cancers, but not in the brain. 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. Researchers from Washington University of St. Louis 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. No one until now has found a way to release tumor-specific biomarkers. The study findings were published in the journal Scientific Reports.
The research team 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. They 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.
Asst. Prof. Hong Chen said, “This noninvasive focused ultrasound-enabled liquid biopsy technique can be useful for long-term monitoring of brain cancer treatment response, where repeated surgical tissue biopsies may not be feasible.”
More Information: Lifei Zhu et al, “Focused Ultrasound-enabled Brain Tumor Liquid Biopsy.” Scientific Reports (2018). DOI:10.1038/s41598-018-24516-7