Cancer-killing nanoparticles don disguises to sneak into the brain
Brain cancers are particularly insidious for many reasons, not least of which is that the brain’s own defense mechanism often prevents treatment. But a new experimental technique has shown success in mice, with carbon nanoparticles able to sneak through the blood-brain barrier and deliver drugs directly to tumors.
The blood-brain barrier has the important job of protecting the brain from any rogue threats, so it’s incredibly picky about what it lets through. That poses a challenge for scientists trying to fight brain cancers and other diseases, and past studies have used magnetic nanoparticles and ultrasound to temporarily open the door for drugs. But that of course runs the risk of other things getting through.
For the new study, the team developed nanoparticles that can not only slip through the blood-brain barrier, but home in on tumors once they get into the brain. Other nanoparticles have been made to do this in the past, but the researchers say their new design is far simpler, since it’s made of just a single compound.
The base is a carbon quantum dot, and this is loaded with molecules that make it appear to be an amino acid, one of the nutrients that’s “allowed” to pass through the blood-brain barrier. Conveniently, this also allows it to bind to a molecule called LAT1, which is present in tumors but not most healthy cells.
By loading these nanoparticles with chemotherapy drugs, they can slip right through the barrier into the brain and then actively seek out tumors like guided missiles. That should reduce the side effects of many chemo drugs, which tend to attack healthy cells as well.
The team tested the technique in mice, giving their nanoparticles the added ability to tag the tumors with fluorescence. That made it clear that the treatment worked as intended, and also demonstrates a new potential way for surgeons to spot tumors.
The results are promising, but the team cautions that there’s still plenty of work to do before this treatment reaches humans.
“It takes a long time before the technology can be translated into clinical applications,” says Jiangbing Zhou, corresponding author of the study. “But this finding suggests a new direction for developing nanoparticles for drug delivery to the brain by targeting LAT1 molecules.”
The research was published in the journal Nature Biomedical Engineering.
Source: Yale University