Russian scientists teach ultrasound find and kill cancer cells

A group of physicists and biologists from Russia under the supervision of MEPhI Professor Viktor Timoshenko has learnt to use silicone nanoparticles for highlighting and destroying of cancer tumors with the help of the ultrasound, not harming healthy tissues, published in the Nanotechnology journal.

“We have found a “part load” mode” for therapeutic treatment of cancer cells, which doesn’t lead to massive explosion of cells but is largely reduced to the destruction of intracellular organs by nanoparticles,” says Andrey Sviridov from the Lomonosov MSU. According to him, it is important that particles’ cover by a biopolymer doesn’t worsen their acoustic properties but leads to a better therapeutic effect.

Lately physicists, chemists, and even nanotechnologists have started to develop new methods of conducting surgeries and therapies, which are conducted without body rupture and damaging of tissues and organs. For example, researchers have developed nanoparticles, which are introduced into tumor and then heated with a laser. This destroys cancer, but doesn’t affect healthy cells. Similar effect is caused by gene therapy and special medicines, preventing growth of vessels in tumor and “choking” cancer cells.

Sviridov and his colleagues under the supervision of MEPhI Professor Viktor Timoshenko have created special silicone nanoparticles, which can also be used for studying of cancer tumors and their destruction, highlighting such particles by ultrasound.

The main problem of such methods of cancer treatment, as scientists say, is that ultrasound and nanoparticles, swallowing it, often act indiscriminately, destroying not only tumor, but also healthy cells. Moreover, such nanoparticles often too quickly dissolve inside the organism, which doesn’t allow use them to observe cells because of their brevity and toxicity.

Timoshenko, Sviridov, and their colleagues have solved this problem, covering nanoparticles from porous silicone with a layer of dextran, biopolymer from dextrose molecules. Such particles, as biologists claim, not only dissolve slower, then their uncovered analogues, but shine under ultraviolet radiation, which allows use them to highlight researched tumors and cell samples.

The particles were tested by scientists on cancer cell cultures, extracted from human larynx, radiating by ultrasound separately and in the presence of nanoparticles.

As experiments have shown, “clear” ultrasound practically doesn’t affect cancer cells, while its combination with nanoparticles, gently kills them, destroying mitochondria and other organelles in cancer cells. Nanoparticles themselves, as multiple-day cell observations have shown, practically don’t affect their lives, unless their concentration exceeds some threshold.

Apart from ultrasound strengthening, the nanoparticles, as researchers say, can be used for delivery of medicines and other molecules inside healthy or cancer cells. Heating with the help of ultrasound or radio waves makes medicines’ molecules more mobile, which will strengthen their efficiency. We shouldn’t expect the nanoparticles to enter medical practice today or tomorrow: they will need to pass a series of clinical tests on animals or volunteers. It may take several years, and such experiments don’t always end up positively.

Scientists from MEPhI, MSU, ITEB of RAS, Lyon University (France), and Trinity-college in Dublin (Ireland) have taken part in the creation of nanoparticles.