Noting the complexity of the human brain and brain tumors, Lawrence Tabak, DDS, PhD, acting director of the National Institutes of Health (NIH), discussed in an April 2023 blog post the findings from a NIH-funded research that may suggest novel nanoparticles can help bypass the blood-brain barrier (BBB) and deliver drugs to treat medulloblastoma, an aggressive brain cancer diagnosed in hundreds of children each year.

Building on previous research in which the team used nanoparticles from chains of sugar molecules called fucoidan to attract P-selectin, the researchers found that when fucoidan nanoparticles bind to P-selectin, they trigger a process that shuttles them across blood vessel walls.

Tabak highlighted the new study, in which the team used mouse models of medulloblastoma to test nanoparticles loaded with a cancer drug. They found that the nanoparticles crossed the intact BBB and into the brain and accumulated at the medulloblastoma tumor site, where P-selectin was most abundant, and not in other healthy parts of the brain. In the mice, Tabak explained that the approach increased treatment efficacy, allowed for lower doses, and produced fewer side effects.

“This raised another possibility,” he said. “Radiation is a standard therapy for children and adults with brain tumors. The researcher found that radiation boosts P-selectin levels, specifically in tumors. The finding suggests that radiation targeting specific parts of the brain prior to nanoparticle treatment could make it even more effective. It also may help to further limit the amount of cancer-fighting drug that reaches healthy brain cells and other parts of the body.”

The fucoidan nanoparticles could, in theory, deliver many different drugs to the brain, Tabak said. The researchers noted their promise for treating brain tumors of all types, including those that spread to the brain from other parts of the body.

“Although much more work is needed, these seaweed-based nanoparticles may also help in delivering drugs to a wide range of other brain conditions, such as multiple sclerosis, stroke, and focal epilepsy, in which seizures arise from a specific part of the brain,” Tabak said. “It’s a discovery that brings new meaning to the familiar adage that good things come in small packages.”