A team of researchers from the California Institute of Technology recently proposed a new technique for killing cancer cells with low-intensity ultrasound. Although the technique is in its early stages, preliminary in vitro studies have shown that sound waves produced by pulses at a specific frequency can effectively destroy cancer cells while maintaining healthy cell integrity.
Several recently published ground-breaking studies have shown that ultrasound does have a useful role in non-invasive cancer treatment. The most advanced method is called high-intensity focused ultrasound (HIFU). The method targets cancer cells with focused and powerful sound waves, heating and destroying diseased tissues.
The challenge of clinically deploying HIFU is how to better aggregate these destructive waves, which are equally vulnerable to destroying healthy tissue. Impressive advances over the past year demonstrate a novel way to use the technology to target prostate cancer, but the problem of collateral damage in healthy tissue remains.
The idea of exposing the body to specific sound frequencies that can cure disease has been around for hundreds of years. Numerous pseudo-scientific claims suggest the discovery of a magical frequency that cures all human diseases, but almost all of these alternative ideas are not supported by rigorous science.
Early studies combined the Greek word for “oncos” and “fractures” and named the process “oncotripsy”. Of course, the idea was still hypothetical at the time, but it attracted like-minded researchers who were keen to test the real-world impact of the process.
Peter Lee, a scientist at City of Hope who was involved in the study, said: “When I heard about it, I thought it was interesting, and if it worked, it could be a revolutionary cancer treatment. “So the researchers began laboratory experiments to test the frequencies, pulse patterns, and duration of various ultrasound frequencies, pulsepatterns, and durations on human cancer cells.
The new study, published in the journal Applied Physics Letters, describes the return of ultrasound at a certain frequency and duration, which can cause the outer membranes of cancer cells to rupture without negative lying on other healthy cells.
“Our results suggest that specific parameters of low-intensity pulsed ultrasound (LIPUS) can induce selective cell division in cancer cells,” the researchers concluded in the new study. In in vitro models, LIPUS, which applies 20 ms PD (pulse duration) at 0.5 MHz, destroys multiple cancer cells while maximizing the therapeutic margin of maintaining healthy blood and immune cells. “
Interestingly, the study showed that although the sound frequency that is considered effective is no different from the frequency commonly used in diagnostic ultrasound scans, cancer cell rupture is detected only when the pulse lasts more than 10 milliseconds. The study notes that most diagnostic ultrasound methods use pulse durations that are much shorter, about 10 microseconds.
“This is an exciting proof of a new type of cancer therapy that does not require cancer to have a unique molecular marker or be placed separately from targeted healthy cells,” explains one of the authors, David Mittelstein. Instead, we may be able to target cancer cells based on their unique physical properties. “
The study was published in Applied Physics Letters.