|laboratory works/ Photo By Alexander Raths via 123RF|
Glioblastoma multiforme is a brain cancer considered to be very difficult to treat because of the blood-brain barrier. Researchers at the Massachusetts Institute of Technology devised a nanoparticle that can cross the barrier and deliver the anticancer drug.
Crossing the Blood-Brain Barrier
According to the American Brain Tumor Association, many substances cannot enter the brain because of the blood-brain barrier, including chemotherapy drugs. Only a small group of anticancer medications like nitrosoureas and temozolomide can cross the barrier. This defensive mechanism of the body is one of many reasons why it is difficult to treat glioblastomas.
At MIT, a team of researchers created a new nanoparticle to offer a better way to treat the disease. In the study, the particles are spherical droplets called liposomes, which can carry substances. The team utilized the two compartments of liposomes – one is inside the core and the other on the fatty shell in the outer layer.
To enable the liposomes to cross the blood-brain barrier, they coated the tiny particles with transferrin, a protein that helps the passage to the barrier and guides them to accumulate in tumor cells. The nanoparticles contain two anticancer drugs: temozolomide stored inside the core and a bromodomain inhibitor on the outer shell. The combination of these drugs can damage the DNA of the tumor cells and disrupt their repair mechanism.
They tested the nanoparticles in mice models with glioblastoma tumors and found that the liposomes were able to cross the barrier. After reaching the tumor site, the outer layer dispensed the inhibitor while the temozolomide was released 24 hours later.
“This is yet another example where the combination of nanoparticle delivery with drugs involving the DNA-damage response can be used successfully to treat cancer,” said Professor Michael Yaffe, a co-author of the study and a member of the Koch Institute.