Brain cancer Treatment: Ultrasound opens the blood-brain barrier
For the first time, specialists managed to open the blood-brain barrier, which prevents the penetration of foreign agents, including drugs into the human brain. This breakthrough should significantly facilitate the treatment of diseases such as Alzheimer's disease and brain cancer.
The blood–brain barrier is a layer of cells covering all the blood vessels of the brain. It protects precious neurons from toxins entering the bloodstream, but at the same time it is the main obstacle to medicines intended for the treatment of diseases of the central nervous system.
Earlier, several groups of researchers managed to crack this barrier in animal experiments. More recently, specialists of the newly created French company CarThera, working under the guidance of Dr. Michael Canney, performed this manipulation on the human brain. They managed to achieve this with the help of an ultrasound implant and injection of microbubbles.
The clinical study involved four patients with recurrent glioblastoma, the most aggressive type of brain cancer. This disease is treated by surgical removal of the tumor and subsequent administration of chemotherapy drugs such as carboplatin. The walls of the blood vessels of such tumors are defective and allow a small amount of chemotherapy drugs into the tumor, but an increase in their throughput would significantly increase the effectiveness of therapy.
To achieve this goal, the authors implanted an ultrasound emitter into the hole in the patient's skull made during the operation to remove the tumor. After that, the patient was injected with microbubbles and turned on the radiator for 2 minutes. As a result, ultrasound waves penetrated a small area of brain tissue measuring 10 mm by 4 mm. The impact of ultrasonic waves caused the microbubbles they encountered on the way to vibrate, which provided a temporary extension of the blood-brain barrier cells. As a result, the treated area of the brain became more accessible for about 6 hours, during which the patient underwent standard chemotherapy.
Drawings from the website carthera.eu
Starting in July, the described procedure was performed once a month for each of the 4 patients. Evaluation of the effectiveness of the antitumor effect of the approach proposed by the researchers will be carried out in a few more months. To date, they claim that the images obtained using magnetic resonance imaging show that a chemical marker injected simultaneously with microbubbles successfully penetrates the blood-brain barrier.
The authors also note that the procedure may find another application. Experiments on animal models of Alzheimer's disease have shown that the opening of the blood-brain barrier itself, even without the introduction of drugs, reduces the number of amyloid plaques associated with the disease in brain tissue. A possible reason for this is the penetration of immune cells into brain tissues that are usually closed from them. Researchers suggest that a similar fate should befall tumor cells hiding from the immune system.
The results of the work are presented at the 4th Symposium on Focused Ultrasound, held on October 12-16 in North Bethesda, Maryland.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the Focused Ultrasound symposium:
Temporary Disruption of the Blood-Brain Barrier Using an Implantable Ultrasound System for Recurrent Glioblastoma Patients Under IV Carboplatin Chemotherapy: Initial Phase 1/2a Clinical Trial Observations.
24.10.2014