Targeted ultrasound-microbubbles “blast apart” and destroy cancer cells
Scientists experimenting with microbubbles as a way of treating cancer have made an exciting new discovery –biomedical engineers at Israel’s Tel Aviv University (TAU) found potential weapons in ultrasound-powered microbubbles, which can tear apart the majority of tumour cells in breast cancer models. The microbubbles are filled with gas and, when subjected to sound waves at certain frequencies, can behave like balloons that expand and contract.
The TAU team found that by directly injecting the microbubbles into tumours in mouse models, and then applying a low frequency ultrasound of 250 kHz to blow them up, they were able to wipe out large numbers of the cancerous cells.
“We discovered that by using low frequencies, microbubbles can significantly expand, until they explode violently,” said Dr. Tali Ilovitsh. “About 80% of tumour cells were destroyed in the explosion, which was positive on its own.”
The TAU team also injected an immunotherapy gene alongside the microbubbles which would signal the hosts’ immune system to attack the remaining tumour cells. The immunotherapy gene was able to pass the membranes of the remaining cells thanks to the explosions, and promptly begun an immune response to finish them off.
“The majority of cancer cells were destroyed by the explosion, and the remaining cells consumed the immunotherapy gene through the holes that were created in their membranes,” Dr. Ilovitsh explains. “The gene caused the cells to produce a substance that triggered the immune system to attack the cancer cell. In fact, our mice had tumours on both sides of their bodies – despite the fact that we conducted the treatment only on one side, the immune system attacked the distant side as well.”
Dr. Ilovitsh hopes to harness this ultrasound-microbubbles combination to pursue the treatment of neurodegenerative diseases like Alzheimer’s. “The blood-brain barrier normally does not allow for medications to penetrate through, but microbubbles can temporary open the barrier, enabling the arrival of the treatment to the target area without the need for an invasive surgical intervention.”
