Israeli scientists have destroyed cancerous tumors in mice by carrying out “controlled explosions” inside the body, which tear through the cancer cells.
They hope to develop the procedure for humans, and say that it could one day become an alternative to tumor-removal surgery for some patients.
They injected veins of lab mice with “nanobubbles” of gas which are 2,500 times smaller than a single grain of salt.
The bubbles spread throughout the whole body as blood circulated, but the scientists chose exactly where they wanted to “detonate” them — solely around the tumor. This was possible because low-frequency ultrasound causes them to pop, so the researchers only applied the ultrasound around the tumor.
“When we apply ultrasound the bubbles grow up to 100 times their initial size,” Dr. Tali Ilovitsh of Tel Aviv University, who led the research, told The Times of Israel. “Then they explode, so we are basically detonating them. The explosion damages the nearby tissue, so it can destroy the tumor.”
She said it’s akin to a controlled explosion used in building demolitions, which is strong enough to wreck the building in question but not to harm other buildings. This is how it targets the tumor but doesn’t harm other parts of the body.
She added that she has high hopes for moving the research from mouse to human application, saying that “the experiment was conducted in a breast cancer tumor mouse model, but it is likely that the treatment will also be effective with other types of tumors, and in the future, also in humans.”
Ilovitsh conducted the peer-reviewed research, which was published in the journal Nanoscale, together with her PhD student Mike Bismuth, with Tel Aviv University colleague Dr. Dov Hershkovitz, and with Prof. Agata Exner from Case Western Reserve University in Cleveland, Ohio, in the United States.
Ultrasound is already successfully used in some human cancer cases. It is applied through the skin to target tumors. However, the ultrasound needed is high-intensity and generates heat, which can damage the tissues near the tumor.
The bubble technique only requires low-intensity ultrasound. This means that it can spare the body collateral damage, Ilovitsh said.
She added that while there has been some research on using bubbles to fight cancer, none has yet translated into actual treatments.
Most of the research has focused on injecting bubbles into the actual tumor, which is an invasive procedure, while hers is unusual in that it attacks the tumor from the bloodstream, which is non-invasive.
“We don’t touch the tumor directly, but rather inject the nanobubbles into the blood,” Ilovitsh explained. “We then take advantage of a unique quality of tumors. Blood vessels in tumors are ‘leaky,’ which means that the nanobubbles don’t stay there but rather many of them leave the vessels and go into the tissue tumor.
“Once they are there, we can use low-intensity ultrasound, which we discovered in previous research detonates bubbles, to attack tumors.
“This approach can help in the treatment of tumors that are located deep within the body, and in addition facilitate the treatment of larger tumor volumes. It could replace, in some cases, surgery to remove tumors. It should be followed by chemotherapy or immunotherapy, just as in the case of surgery. This is promising research.”