The technique combines ultrasound application and tumor-targeted microbubbles.

In a research conducted at Tel Aviv University, scientists developed non-invasive technology for delivering genes into breast cancer cells; this research was led by Dr. Tail Ilovitsh of Biomedical Engineering Department.

This non-invasive technology is based on treating cancer by mainly using the ultrasound technique combining with the tumor-targeted microbubbles. This technique basically starts with the activation of the ultrasound, then the microbubbles bursts on the targeted cancerous cells. The explosion creates holes in their cell membrane that in turn promote gene delivery.

This research was conducted for around a period of 2 years, and the results were published in National Proceedings of the National Academy of Sciences (PNAS).

Dr. Ilovitsh, at Professor Katherine Ferrara’s lab, developed this technology, when she was pursuing her Post-Doctorate Research at Stanford University. This technique used a lower frequency ultrasound of around 250 kHz aimed to explode the microscopic tumor-targeted bubbles. In-vivo examination showed 80% of the tumor cells were killed.

Microbubbles

The Microbubbles are basically microscopic bubbles filled with gas, having a much smaller diameter of about one-tenth of the blood vessel. Dr. Ilovitsh explained that the microbubbles start acting like balloons due to soundwaves at a definite pressure and frequency. Through this process, the transfer of the substances from blood vessels to surrounding tissues increased.

Her team used lower frequencies as compared to those applied previously, resulting in microbubbles enlargement. They realized this method could be used as a platform for cancer treatment. They started to inject microbubbles directly into the tumors.

Tumor-targeted microbubbles

Dr. Ilvitsh and her team utilized the tumor-targeted microbubbles associated with tumor cell membranes at the instance of burst and administered them directly into the tumors in a mouse model.

Around 80% of tumor cells were demolished in the explosion and were positive on its own, she said.

The targeted treatment was safer and worthwhile, exploded most of the tumor. In order to prevent the expansion of the leftover cancerous cells, they required to explode all the tumor cells. Therefore, they introduced an immunotherapy gene beside the microbubbles. Gene acted as a Trojan horse and signaled the immune system to invade the cancerous cells.

The gene itself cannot penetrate into the cancer cells. So the gene supposed to raise the immune system efficiency was co-injected along with the microbubbles. Out of remaining cancer cells, 20% cells after the explosion got membrane pores. These pored allowed the entry of the gene into the cells. This in turn activated an immune response that exploded the cancer cells.

 Dr. Ilvitsh also stated that the majority of the cancerous cells were destroyed by the explosion. Leftover cells utilized the immunotherapy gene via the holes that were formed in their membranes.

The gene resulted in cells developing a substance, which activated the immune system to affect the cancer cell.

The mice they used were having tumors on both sides of their bodies. However they performed the treatment on one side only, the immune system affected the other side also.

In Future

Dr. Ilovitsh said that in the future she is planning to experiment with this technology as a non-invasive treatment for brain-related ailments such as brain tumors and other neurodegenerative states .i.e. Alzheimer’s and Parkinson’s disorders. According to her the blood-brain barrier never allow the medications to go through. But the microbubbles can alternatively open the barrier, allowing the treatment to the targeted region without invasive surgical intervention.