ANN ARBOR, Mich. – There is a new synthetic protein nanoparticle that is capable of slipping past the nearly impermeable blood-brain barrier in mice and could deliver cancer-killing drugs directly to malignant brain tumors, University of Michigan researchers said.
The study is the first to demonstrate an intravenous medication that can cross the blood-brain barrier. Researchers believe the discovery could enable new clinical therapies for treating glioblastoma, a common and aggressive form of brain cancer in adults.
The median survival for patients with glioblastoma is around 18 months. The average 5-year survival rate is below 5 percent. Combined with radiation, the new intravenously injected therapy led to long-term survival in seven out of eight mice. When those seven mice experienced a recurrence of glioblastoma, their immune responses kicked in to prevent cancer’s regrowth.
“It’s still a bit of a miracle to us,” said Joerg Lahann, the Wolfgang Pauli Collegiate Professor of Chemical Engineering and a co-senior author of the study. “Where we would expect to see some levels of tumor growth, they just didn’t form when we rechallenged the mice. I’ve worked in this field for more than 10 years and have not seen anything like this.”
The findings suggest that the combination of therapeutic drugs and delivery methods resulted in immunological memory.
“This is a huge step toward clinical implementation,” said Maria Castro, the R.C. Schneider Collegiate Professor of Neurosurgery and a co-senior author of the study. “This is the first study to demonstrate the ability to deliver therapeutic drugs systemically, or intravenously, that can also cross the blood-brain barrier to reach tumors.”